fix alignment of centered items ... title and footer
[rrdtool.git] / src / rrd_graph.c
1 /****************************************************************************
2  * RRDtool 1.4.3  Copyright by Tobi Oetiker, 1997-2010
3  ****************************************************************************
4  * rrd__graph.c  produce graphs from data in rrdfiles
5  ****************************************************************************/
6
7
8 #include <sys/stat.h>
9
10 #ifdef WIN32
11 #include "strftime.h"
12 #endif
13
14 #include "rrd_tool.h"
15
16 /* for basename */
17 #ifdef HAVE_LIBGEN_H
18 #  include <libgen.h>
19 #else
20 #include "plbasename.h"
21 #endif
22
23 #if defined(WIN32) && !defined(__CYGWIN__) && !defined(__CYGWIN32__)
24 #include <io.h>
25 #include <fcntl.h>
26 #endif
27
28 #include <time.h>
29
30 #include <locale.h>
31
32 #ifdef HAVE_LANGINFO_H
33 #include <langinfo.h>
34 #endif
35
36 #include "rrd_graph.h"
37 #include "rrd_client.h"
38
39 /* some constant definitions */
40
41
42
43 #ifndef RRD_DEFAULT_FONT
44 /* there is special code later to pick Cour.ttf when running on windows */
45 #define RRD_DEFAULT_FONT "DejaVu Sans Mono,Bitstream Vera Sans Mono,monospace,Courier"
46 #endif
47
48 text_prop_t text_prop[] = {
49     {8.0, RRD_DEFAULT_FONT,NULL}
50     ,                   /* default */
51     {9.0, RRD_DEFAULT_FONT,NULL}
52     ,                   /* title */
53     {7.0, RRD_DEFAULT_FONT,NULL}
54     ,                   /* axis */
55     {8.0, RRD_DEFAULT_FONT,NULL}
56     ,                   /* unit */
57     {8.0, RRD_DEFAULT_FONT,NULL} /* legend */
58     ,
59     {5.5, RRD_DEFAULT_FONT,NULL} /* watermark */
60 };
61
62 xlab_t    xlab[] = {
63     {0, 0, TMT_SECOND, 30, TMT_MINUTE, 5, TMT_MINUTE, 5, 0, "%H:%M"}
64     ,
65     {2, 0, TMT_MINUTE, 1, TMT_MINUTE, 5, TMT_MINUTE, 5, 0, "%H:%M"}
66     ,
67     {5, 0, TMT_MINUTE, 2, TMT_MINUTE, 10, TMT_MINUTE, 10, 0, "%H:%M"}
68     ,
69     {10, 0, TMT_MINUTE, 5, TMT_MINUTE, 20, TMT_MINUTE, 20, 0, "%H:%M"}
70     ,
71     {30, 0, TMT_MINUTE, 10, TMT_HOUR, 1, TMT_HOUR, 1, 0, "%H:%M"}
72     ,
73     {60, 0, TMT_MINUTE, 30, TMT_HOUR, 2, TMT_HOUR, 2, 0, "%H:%M"}
74     ,
75     {60, 24 * 3600, TMT_MINUTE, 30, TMT_HOUR, 2, TMT_HOUR, 6, 0, "%a %H:%M"}
76     ,
77     {180, 0, TMT_HOUR, 1, TMT_HOUR, 6, TMT_HOUR, 6, 0, "%H:%M"}
78     ,
79     {180, 24 * 3600, TMT_HOUR, 1, TMT_HOUR, 6, TMT_HOUR, 12, 0, "%a %H:%M"}
80     ,
81     /*{300,             0,   TMT_HOUR,3,    TMT_HOUR,12,   TMT_HOUR,12,    12*3600,"%a %p"},  this looks silly */
82     {600, 0, TMT_HOUR, 6, TMT_DAY, 1, TMT_DAY, 1, 24 * 3600, "%a"}
83     ,
84     {1200, 0, TMT_HOUR, 6, TMT_DAY, 1, TMT_DAY, 1, 24 * 3600, "%d"}
85     ,
86     {1800, 0, TMT_HOUR, 12, TMT_DAY, 1, TMT_DAY, 2, 24 * 3600, "%a %d"}
87     ,
88     {2400, 0, TMT_HOUR, 12, TMT_DAY, 1, TMT_DAY, 2, 24 * 3600, "%a"}
89     ,
90     {3600, 0, TMT_DAY, 1, TMT_WEEK, 1, TMT_WEEK, 1, 7 * 24 * 3600, "Week %V"}
91     ,
92     {3 * 3600, 0, TMT_WEEK, 1, TMT_MONTH, 1, TMT_WEEK, 2, 7 * 24 * 3600,
93      "Week %V"}
94     ,
95     {6 * 3600, 0, TMT_MONTH, 1, TMT_MONTH, 1, TMT_MONTH, 1, 30 * 24 * 3600,
96      "%b"}
97     ,
98     {48 * 3600, 0, TMT_MONTH, 1, TMT_MONTH, 3, TMT_MONTH, 3, 30 * 24 * 3600,
99      "%b"}
100     ,
101     {315360, 0, TMT_MONTH, 3, TMT_YEAR, 1, TMT_YEAR, 1, 365 * 24 * 3600, "%Y"}
102     ,
103     {10 * 24 * 3600, 0, TMT_YEAR, 1, TMT_YEAR, 1, TMT_YEAR, 1,
104      365 * 24 * 3600, "%y"}
105     ,
106     {-1, 0, TMT_MONTH, 0, TMT_MONTH, 0, TMT_MONTH, 0, 0, ""}
107 };
108
109 /* sensible y label intervals ...*/
110
111 ylab_t    ylab[] = {
112     {0.1, {1, 2, 5, 10}
113      }
114     ,
115     {0.2, {1, 5, 10, 20}
116      }
117     ,
118     {0.5, {1, 2, 4, 10}
119      }
120     ,
121     {1.0, {1, 2, 5, 10}
122      }
123     ,
124     {2.0, {1, 5, 10, 20}
125      }
126     ,
127     {5.0, {1, 2, 4, 10}
128      }
129     ,
130     {10.0, {1, 2, 5, 10}
131      }
132     ,
133     {20.0, {1, 5, 10, 20}
134      }
135     ,
136     {50.0, {1, 2, 4, 10}
137      }
138     ,
139     {100.0, {1, 2, 5, 10}
140      }
141     ,
142     {200.0, {1, 5, 10, 20}
143      }
144     ,
145     {500.0, {1, 2, 4, 10}
146      }
147     ,
148     {0.0, {0, 0, 0, 0}
149      }
150 };
151
152
153 gfx_color_t graph_col[] =   /* default colors */
154 {
155     {1.00, 1.00, 1.00, 1.00},   /* canvas     */
156     {0.95, 0.95, 0.95, 1.00},   /* background */
157     {0.81, 0.81, 0.81, 1.00},   /* shade A    */
158     {0.62, 0.62, 0.62, 1.00},   /* shade B    */
159     {0.56, 0.56, 0.56, 0.75},   /* grid       */
160     {0.87, 0.31, 0.31, 0.60},   /* major grid */
161     {0.00, 0.00, 0.00, 1.00},   /* font       */
162     {0.50, 0.12, 0.12, 1.00},   /* arrow      */
163     {0.12, 0.12, 0.12, 1.00},   /* axis       */
164     {0.00, 0.00, 0.00, 1.00}    /* frame      */
165 };
166
167
168 /* #define DEBUG */
169
170 #ifdef DEBUG
171 # define DPRINT(x)    (void)(printf x, printf("\n"))
172 #else
173 # define DPRINT(x)
174 #endif
175
176
177 /* initialize with xtr(im,0); */
178 int xtr(
179     image_desc_t *im,
180     time_t mytime)
181 {
182     static double pixie;
183
184     if (mytime == 0) {
185         pixie = (double) im->xsize / (double) (im->end - im->start);
186         return im->xorigin;
187     }
188     return (int) ((double) im->xorigin + pixie * (mytime - im->start));
189 }
190
191 /* translate data values into y coordinates */
192 double ytr(
193     image_desc_t *im,
194     double value)
195 {
196     static double pixie;
197     double    yval;
198
199     if (isnan(value)) {
200         if (!im->logarithmic)
201             pixie = (double) im->ysize / (im->maxval - im->minval);
202         else
203             pixie =
204                 (double) im->ysize / (log10(im->maxval) - log10(im->minval));
205         yval = im->yorigin;
206     } else if (!im->logarithmic) {
207         yval = im->yorigin - pixie * (value - im->minval);
208     } else {
209         if (value < im->minval) {
210             yval = im->yorigin;
211         } else {
212             yval = im->yorigin - pixie * (log10(value) - log10(im->minval));
213         }
214     }
215     return yval;
216 }
217
218
219
220 /* conversion function for symbolic entry names */
221
222
223 #define conv_if(VV,VVV) \
224    if (strcmp(#VV, string) == 0) return VVV ;
225
226 enum gf_en gf_conv(
227     char *string)
228 {
229
230     conv_if(PRINT, GF_PRINT);
231     conv_if(GPRINT, GF_GPRINT);
232     conv_if(COMMENT, GF_COMMENT);
233     conv_if(HRULE, GF_HRULE);
234     conv_if(VRULE, GF_VRULE);
235     conv_if(LINE, GF_LINE);
236     conv_if(AREA, GF_AREA);
237         conv_if(GRAD, GF_GRAD);
238     conv_if(STACK, GF_STACK);
239     conv_if(TICK, GF_TICK);
240     conv_if(TEXTALIGN, GF_TEXTALIGN);
241     conv_if(DEF, GF_DEF);
242     conv_if(CDEF, GF_CDEF);
243     conv_if(VDEF, GF_VDEF);
244     conv_if(XPORT, GF_XPORT);
245     conv_if(SHIFT, GF_SHIFT);
246
247     return (enum gf_en)(-1);
248 }
249
250 enum gfx_if_en if_conv(
251     char *string)
252 {
253
254     conv_if(PNG, IF_PNG);
255     conv_if(SVG, IF_SVG);
256     conv_if(EPS, IF_EPS);
257     conv_if(PDF, IF_PDF);
258
259     return (enum gfx_if_en)(-1);
260 }
261
262 enum tmt_en tmt_conv(
263     char *string)
264 {
265
266     conv_if(SECOND, TMT_SECOND);
267     conv_if(MINUTE, TMT_MINUTE);
268     conv_if(HOUR, TMT_HOUR);
269     conv_if(DAY, TMT_DAY);
270     conv_if(WEEK, TMT_WEEK);
271     conv_if(MONTH, TMT_MONTH);
272     conv_if(YEAR, TMT_YEAR);
273     return (enum tmt_en)(-1);
274 }
275
276 enum grc_en grc_conv(
277     char *string)
278 {
279
280     conv_if(BACK, GRC_BACK);
281     conv_if(CANVAS, GRC_CANVAS);
282     conv_if(SHADEA, GRC_SHADEA);
283     conv_if(SHADEB, GRC_SHADEB);
284     conv_if(GRID, GRC_GRID);
285     conv_if(MGRID, GRC_MGRID);
286     conv_if(FONT, GRC_FONT);
287     conv_if(ARROW, GRC_ARROW);
288     conv_if(AXIS, GRC_AXIS);
289     conv_if(FRAME, GRC_FRAME);
290
291     return (enum grc_en)(-1);
292 }
293
294 enum text_prop_en text_prop_conv(
295     char *string)
296 {
297
298     conv_if(DEFAULT, TEXT_PROP_DEFAULT);
299     conv_if(TITLE, TEXT_PROP_TITLE);
300     conv_if(AXIS, TEXT_PROP_AXIS);
301     conv_if(UNIT, TEXT_PROP_UNIT);
302     conv_if(LEGEND, TEXT_PROP_LEGEND);
303     conv_if(WATERMARK, TEXT_PROP_WATERMARK);
304     return (enum text_prop_en)(-1);
305 }
306
307
308 #undef conv_if
309
310 int im_free(
311     image_desc_t *im)
312 {
313     unsigned long i, ii;
314     cairo_status_t status = (cairo_status_t) 0;
315
316     if (im == NULL)
317         return 0;
318
319     if (im->daemon_addr != NULL)
320       free(im->daemon_addr);
321
322     for (i = 0; i < (unsigned) im->gdes_c; i++) {
323         if (im->gdes[i].data_first) {
324             /* careful here, because a single pointer can occur several times */
325             free(im->gdes[i].data);
326             if (im->gdes[i].ds_namv) {
327                 for (ii = 0; ii < im->gdes[i].ds_cnt; ii++)
328                     free(im->gdes[i].ds_namv[ii]);
329                 free(im->gdes[i].ds_namv);
330             }
331         }
332         /* free allocated memory used for dashed lines */
333         if (im->gdes[i].p_dashes != NULL)
334             free(im->gdes[i].p_dashes);
335
336         free(im->gdes[i].p_data);
337         free(im->gdes[i].rpnp);
338     }
339     free(im->gdes);
340
341     for (i = 0; i < DIM(text_prop);i++){
342         pango_font_description_free(im->text_prop[i].font_desc);
343         im->text_prop[i].font_desc = NULL;
344     }
345
346     if (im->font_options)
347         cairo_font_options_destroy(im->font_options);
348
349     if (im->cr) {
350         status = cairo_status(im->cr);
351         cairo_destroy(im->cr);
352     }
353
354
355     if (im->rendered_image) {
356         free(im->rendered_image);
357     }
358
359     if (im->layout) {
360         g_object_unref (im->layout);
361     }
362
363     if (im->surface)
364         cairo_surface_destroy(im->surface);
365
366     if (status)
367         fprintf(stderr, "OOPS: Cairo has issues it can't even die: %s\n",
368                 cairo_status_to_string(status));
369
370     return 0;
371 }
372
373 /* find SI magnitude symbol for the given number*/
374 void auto_scale(
375     image_desc_t *im,   /* image description */
376     double *value,
377     char **symb_ptr,
378     double *magfact)
379 {
380
381     char     *symbol[] = { "a", /* 10e-18 Atto */
382         "f",            /* 10e-15 Femto */
383         "p",            /* 10e-12 Pico */
384         "n",            /* 10e-9  Nano */
385         "u",            /* 10e-6  Micro */
386         "m",            /* 10e-3  Milli */
387         " ",            /* Base */
388         "k",            /* 10e3   Kilo */
389         "M",            /* 10e6   Mega */
390         "G",            /* 10e9   Giga */
391         "T",            /* 10e12  Tera */
392         "P",            /* 10e15  Peta */
393         "E"
394     };                  /* 10e18  Exa */
395
396     int       symbcenter = 6;
397     int       sindex;
398
399     if (*value == 0.0 || isnan(*value)) {
400         sindex = 0;
401         *magfact = 1.0;
402     } else {
403         sindex = floor(log(fabs(*value)) / log((double) im->base));
404         *magfact = pow((double) im->base, (double) sindex);
405         (*value) /= (*magfact);
406     }
407     if (sindex <= symbcenter && sindex >= -symbcenter) {
408         (*symb_ptr) = symbol[sindex + symbcenter];
409     } else {
410         (*symb_ptr) = "?";
411     }
412 }
413
414
415 static char si_symbol[] = {
416     'a',                /* 10e-18 Atto */
417     'f',                /* 10e-15 Femto */
418     'p',                /* 10e-12 Pico */
419     'n',                /* 10e-9  Nano */
420     'u',                /* 10e-6  Micro */
421     'm',                /* 10e-3  Milli */
422     ' ',                /* Base */
423     'k',                /* 10e3   Kilo */
424     'M',                /* 10e6   Mega */
425     'G',                /* 10e9   Giga */
426     'T',                /* 10e12  Tera */
427     'P',                /* 10e15  Peta */
428     'E',                /* 10e18  Exa */
429 };
430 static const int si_symbcenter = 6;
431
432 /* find SI magnitude symbol for the numbers on the y-axis*/
433 void si_unit(
434     image_desc_t *im    /* image description */
435     )
436 {
437
438     double    digits, viewdigits = 0;
439
440     digits =
441         floor(log(max(fabs(im->minval), fabs(im->maxval))) /
442               log((double) im->base));
443
444     if (im->unitsexponent != 9999) {
445         /* unitsexponent = 9, 6, 3, 0, -3, -6, -9, etc */
446         viewdigits = floor((double)(im->unitsexponent / 3));
447     } else {
448         viewdigits = digits;
449     }
450
451     im->magfact = pow((double) im->base, digits);
452
453 #ifdef DEBUG
454     printf("digits %6.3f  im->magfact %6.3f\n", digits, im->magfact);
455 #endif
456
457     im->viewfactor = im->magfact / pow((double) im->base, viewdigits);
458
459     if (((viewdigits + si_symbcenter) < sizeof(si_symbol)) &&
460         ((viewdigits + si_symbcenter) >= 0))
461         im->symbol = si_symbol[(int) viewdigits + si_symbcenter];
462     else
463         im->symbol = '?';
464 }
465
466 /*  move min and max values around to become sensible */
467
468 void expand_range(
469     image_desc_t *im)
470 {
471     double    sensiblevalues[] = { 1000.0, 900.0, 800.0, 750.0, 700.0,
472         600.0, 500.0, 400.0, 300.0, 250.0,
473         200.0, 125.0, 100.0, 90.0, 80.0,
474         75.0, 70.0, 60.0, 50.0, 40.0, 30.0,
475         25.0, 20.0, 10.0, 9.0, 8.0,
476         7.0, 6.0, 5.0, 4.0, 3.5, 3.0,
477         2.5, 2.0, 1.8, 1.5, 1.2, 1.0,
478         0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.0, -1
479     };
480
481     double    scaled_min, scaled_max;
482     double    adj;
483     int       i;
484
485
486
487 #ifdef DEBUG
488     printf("Min: %6.2f Max: %6.2f MagFactor: %6.2f\n",
489            im->minval, im->maxval, im->magfact);
490 #endif
491
492     if (isnan(im->ygridstep)) {
493         if (im->extra_flags & ALTAUTOSCALE) {
494             /* measure the amplitude of the function. Make sure that
495                graph boundaries are slightly higher then max/min vals
496                so we can see amplitude on the graph */
497             double    delt, fact;
498
499             delt = im->maxval - im->minval;
500             adj = delt * 0.1;
501             fact = 2.0 * pow(10.0,
502                              floor(log10
503                                    (max(fabs(im->minval), fabs(im->maxval)) /
504                                     im->magfact)) - 2);
505             if (delt < fact) {
506                 adj = (fact - delt) * 0.55;
507 #ifdef DEBUG
508                 printf
509                     ("Min: %6.2f Max: %6.2f delt: %6.2f fact: %6.2f adj: %6.2f\n",
510                      im->minval, im->maxval, delt, fact, adj);
511 #endif
512             }
513             im->minval -= adj;
514             im->maxval += adj;
515         } else if (im->extra_flags & ALTAUTOSCALE_MIN) {
516             /* measure the amplitude of the function. Make sure that
517                graph boundaries are slightly lower than min vals
518                so we can see amplitude on the graph */
519             adj = (im->maxval - im->minval) * 0.1;
520             im->minval -= adj;
521         } else if (im->extra_flags & ALTAUTOSCALE_MAX) {
522             /* measure the amplitude of the function. Make sure that
523                graph boundaries are slightly higher than max vals
524                so we can see amplitude on the graph */
525             adj = (im->maxval - im->minval) * 0.1;
526             im->maxval += adj;
527         } else {
528             scaled_min = im->minval / im->magfact;
529             scaled_max = im->maxval / im->magfact;
530
531             for (i = 1; sensiblevalues[i] > 0; i++) {
532                 if (sensiblevalues[i - 1] >= scaled_min &&
533                     sensiblevalues[i] <= scaled_min)
534                     im->minval = sensiblevalues[i] * (im->magfact);
535
536                 if (-sensiblevalues[i - 1] <= scaled_min &&
537                     -sensiblevalues[i] >= scaled_min)
538                     im->minval = -sensiblevalues[i - 1] * (im->magfact);
539
540                 if (sensiblevalues[i - 1] >= scaled_max &&
541                     sensiblevalues[i] <= scaled_max)
542                     im->maxval = sensiblevalues[i - 1] * (im->magfact);
543
544                 if (-sensiblevalues[i - 1] <= scaled_max &&
545                     -sensiblevalues[i] >= scaled_max)
546                     im->maxval = -sensiblevalues[i] * (im->magfact);
547             }
548         }
549     } else {
550         /* adjust min and max to the grid definition if there is one */
551         im->minval = (double) im->ylabfact * im->ygridstep *
552             floor(im->minval / ((double) im->ylabfact * im->ygridstep));
553         im->maxval = (double) im->ylabfact * im->ygridstep *
554             ceil(im->maxval / ((double) im->ylabfact * im->ygridstep));
555     }
556
557 #ifdef DEBUG
558     fprintf(stderr, "SCALED Min: %6.2f Max: %6.2f Factor: %6.2f\n",
559             im->minval, im->maxval, im->magfact);
560 #endif
561 }
562
563
564 void apply_gridfit(
565     image_desc_t *im)
566 {
567     if (isnan(im->minval) || isnan(im->maxval))
568         return;
569     ytr(im, DNAN);
570     if (im->logarithmic) {
571         double    ya, yb, ypix, ypixfrac;
572         double    log10_range = log10(im->maxval) - log10(im->minval);
573
574         ya = pow((double) 10, floor(log10(im->minval)));
575         while (ya < im->minval)
576             ya *= 10;
577         if (ya > im->maxval)
578             return;     /* don't have y=10^x gridline */
579         yb = ya * 10;
580         if (yb <= im->maxval) {
581             /* we have at least 2 y=10^x gridlines.
582                Make sure distance between them in pixels
583                are an integer by expanding im->maxval */
584             double    y_pixel_delta = ytr(im, ya) - ytr(im, yb);
585             double    factor = y_pixel_delta / floor(y_pixel_delta);
586             double    new_log10_range = factor * log10_range;
587             double    new_ymax_log10 = log10(im->minval) + new_log10_range;
588
589             im->maxval = pow(10, new_ymax_log10);
590             ytr(im, DNAN);  /* reset precalc */
591             log10_range = log10(im->maxval) - log10(im->minval);
592         }
593         /* make sure first y=10^x gridline is located on
594            integer pixel position by moving scale slightly
595            downwards (sub-pixel movement) */
596         ypix = ytr(im, ya) + im->ysize; /* add im->ysize so it always is positive */
597         ypixfrac = ypix - floor(ypix);
598         if (ypixfrac > 0 && ypixfrac < 1) {
599             double    yfrac = ypixfrac / im->ysize;
600
601             im->minval = pow(10, log10(im->minval) - yfrac * log10_range);
602             im->maxval = pow(10, log10(im->maxval) - yfrac * log10_range);
603             ytr(im, DNAN);  /* reset precalc */
604         }
605     } else {
606         /* Make sure we have an integer pixel distance between
607            each minor gridline */
608         double    ypos1 = ytr(im, im->minval);
609         double    ypos2 = ytr(im, im->minval + im->ygrid_scale.gridstep);
610         double    y_pixel_delta = ypos1 - ypos2;
611         double    factor = y_pixel_delta / floor(y_pixel_delta);
612         double    new_range = factor * (im->maxval - im->minval);
613         double    gridstep = im->ygrid_scale.gridstep;
614         double    minor_y, minor_y_px, minor_y_px_frac;
615
616         if (im->maxval > 0.0)
617             im->maxval = im->minval + new_range;
618         else
619             im->minval = im->maxval - new_range;
620         ytr(im, DNAN);  /* reset precalc */
621         /* make sure first minor gridline is on integer pixel y coord */
622         minor_y = gridstep * floor(im->minval / gridstep);
623         while (minor_y < im->minval)
624             minor_y += gridstep;
625         minor_y_px = ytr(im, minor_y) + im->ysize;  /* ensure > 0 by adding ysize */
626         minor_y_px_frac = minor_y_px - floor(minor_y_px);
627         if (minor_y_px_frac > 0 && minor_y_px_frac < 1) {
628             double    yfrac = minor_y_px_frac / im->ysize;
629             double    range = im->maxval - im->minval;
630
631             im->minval = im->minval - yfrac * range;
632             im->maxval = im->maxval - yfrac * range;
633             ytr(im, DNAN);  /* reset precalc */
634         }
635         calc_horizontal_grid(im);   /* recalc with changed im->maxval */
636     }
637 }
638
639 /* reduce data reimplementation by Alex */
640
641 void reduce_data(
642     enum cf_en cf,      /* which consolidation function ? */
643     unsigned long cur_step, /* step the data currently is in */
644     time_t *start,      /* start, end and step as requested ... */
645     time_t *end,        /* ... by the application will be   ... */
646     unsigned long *step,    /* ... adjusted to represent reality    */
647     unsigned long *ds_cnt,  /* number of data sources in file */
648     rrd_value_t **data)
649 {                       /* two dimensional array containing the data */
650     int       i, reduce_factor = ceil((double) (*step) / (double) cur_step);
651     unsigned long col, dst_row, row_cnt, start_offset, end_offset, skiprows =
652         0;
653     rrd_value_t *srcptr, *dstptr;
654
655     (*step) = cur_step * reduce_factor; /* set new step size for reduced data */
656     dstptr = *data;
657     srcptr = *data;
658     row_cnt = ((*end) - (*start)) / cur_step;
659
660 #ifdef DEBUG
661 #define DEBUG_REDUCE
662 #endif
663 #ifdef DEBUG_REDUCE
664     printf("Reducing %lu rows with factor %i time %lu to %lu, step %lu\n",
665            row_cnt, reduce_factor, *start, *end, cur_step);
666     for (col = 0; col < row_cnt; col++) {
667         printf("time %10lu: ", *start + (col + 1) * cur_step);
668         for (i = 0; i < *ds_cnt; i++)
669             printf(" %8.2e", srcptr[*ds_cnt * col + i]);
670         printf("\n");
671     }
672 #endif
673
674     /* We have to combine [reduce_factor] rows of the source
675      ** into one row for the destination.  Doing this we also
676      ** need to take care to combine the correct rows.  First
677      ** alter the start and end time so that they are multiples
678      ** of the new step time.  We cannot reduce the amount of
679      ** time so we have to move the end towards the future and
680      ** the start towards the past.
681      */
682     end_offset = (*end) % (*step);
683     start_offset = (*start) % (*step);
684
685     /* If there is a start offset (which cannot be more than
686      ** one destination row), skip the appropriate number of
687      ** source rows and one destination row.  The appropriate
688      ** number is what we do know (start_offset/cur_step) of
689      ** the new interval (*step/cur_step aka reduce_factor).
690      */
691 #ifdef DEBUG_REDUCE
692     printf("start_offset: %lu  end_offset: %lu\n", start_offset, end_offset);
693     printf("row_cnt before:  %lu\n", row_cnt);
694 #endif
695     if (start_offset) {
696         (*start) = (*start) - start_offset;
697         skiprows = reduce_factor - start_offset / cur_step;
698         srcptr += skiprows * *ds_cnt;
699         for (col = 0; col < (*ds_cnt); col++)
700             *dstptr++ = DNAN;
701         row_cnt -= skiprows;
702     }
703 #ifdef DEBUG_REDUCE
704     printf("row_cnt between: %lu\n", row_cnt);
705 #endif
706
707     /* At the end we have some rows that are not going to be
708      ** used, the amount is end_offset/cur_step
709      */
710     if (end_offset) {
711         (*end) = (*end) - end_offset + (*step);
712         skiprows = end_offset / cur_step;
713         row_cnt -= skiprows;
714     }
715 #ifdef DEBUG_REDUCE
716     printf("row_cnt after:   %lu\n", row_cnt);
717 #endif
718
719 /* Sanity check: row_cnt should be multiple of reduce_factor */
720 /* if this gets triggered, something is REALLY WRONG ... we die immediately */
721
722     if (row_cnt % reduce_factor) {
723         printf("SANITY CHECK: %lu rows cannot be reduced by %i \n",
724                row_cnt, reduce_factor);
725         printf("BUG in reduce_data()\n");
726         exit(1);
727     }
728
729     /* Now combine reduce_factor intervals at a time
730      ** into one interval for the destination.
731      */
732
733     for (dst_row = 0; (long int) row_cnt >= reduce_factor; dst_row++) {
734         for (col = 0; col < (*ds_cnt); col++) {
735             rrd_value_t newval = DNAN;
736             unsigned long validval = 0;
737
738             for (i = 0; i < reduce_factor; i++) {
739                 if (isnan(srcptr[i * (*ds_cnt) + col])) {
740                     continue;
741                 }
742                 validval++;
743                 if (isnan(newval))
744                     newval = srcptr[i * (*ds_cnt) + col];
745                 else {
746                     switch (cf) {
747                     case CF_HWPREDICT:
748                     case CF_MHWPREDICT:
749                     case CF_DEVSEASONAL:
750                     case CF_DEVPREDICT:
751                     case CF_SEASONAL:
752                     case CF_AVERAGE:
753                         newval += srcptr[i * (*ds_cnt) + col];
754                         break;
755                     case CF_MINIMUM:
756                         newval = min(newval, srcptr[i * (*ds_cnt) + col]);
757                         break;
758                     case CF_FAILURES:
759                         /* an interval contains a failure if any subintervals contained a failure */
760                     case CF_MAXIMUM:
761                         newval = max(newval, srcptr[i * (*ds_cnt) + col]);
762                         break;
763                     case CF_LAST:
764                         newval = srcptr[i * (*ds_cnt) + col];
765                         break;
766                     }
767                 }
768             }
769             if (validval == 0) {
770                 newval = DNAN;
771             } else {
772                 switch (cf) {
773                 case CF_HWPREDICT:
774                 case CF_MHWPREDICT:
775                 case CF_DEVSEASONAL:
776                 case CF_DEVPREDICT:
777                 case CF_SEASONAL:
778                 case CF_AVERAGE:
779                     newval /= validval;
780                     break;
781                 case CF_MINIMUM:
782                 case CF_FAILURES:
783                 case CF_MAXIMUM:
784                 case CF_LAST:
785                     break;
786                 }
787             }
788             *dstptr++ = newval;
789         }
790         srcptr += (*ds_cnt) * reduce_factor;
791         row_cnt -= reduce_factor;
792     }
793     /* If we had to alter the endtime, we didn't have enough
794      ** source rows to fill the last row. Fill it with NaN.
795      */
796     if (end_offset)
797         for (col = 0; col < (*ds_cnt); col++)
798             *dstptr++ = DNAN;
799 #ifdef DEBUG_REDUCE
800     row_cnt = ((*end) - (*start)) / *step;
801     srcptr = *data;
802     printf("Done reducing. Currently %lu rows, time %lu to %lu, step %lu\n",
803            row_cnt, *start, *end, *step);
804     for (col = 0; col < row_cnt; col++) {
805         printf("time %10lu: ", *start + (col + 1) * (*step));
806         for (i = 0; i < *ds_cnt; i++)
807             printf(" %8.2e", srcptr[*ds_cnt * col + i]);
808         printf("\n");
809     }
810 #endif
811 }
812
813
814 /* get the data required for the graphs from the
815    relevant rrds ... */
816
817 int data_fetch(
818     image_desc_t *im)
819 {
820     int       i, ii;
821     int       skip;
822
823     /* pull the data from the rrd files ... */
824     for (i = 0; i < (int) im->gdes_c; i++) {
825         /* only GF_DEF elements fetch data */
826         if (im->gdes[i].gf != GF_DEF)
827             continue;
828
829         skip = 0;
830         /* do we have it already ? */
831         for (ii = 0; ii < i; ii++) {
832             if (im->gdes[ii].gf != GF_DEF)
833                 continue;
834             if ((strcmp(im->gdes[i].rrd, im->gdes[ii].rrd) == 0)
835                 && (im->gdes[i].cf == im->gdes[ii].cf)
836                 && (im->gdes[i].cf_reduce == im->gdes[ii].cf_reduce)
837                 && (im->gdes[i].start_orig == im->gdes[ii].start_orig)
838                 && (im->gdes[i].end_orig == im->gdes[ii].end_orig)
839                 && (im->gdes[i].step_orig == im->gdes[ii].step_orig)) {
840                 /* OK, the data is already there.
841                  ** Just copy the header portion
842                  */
843                 im->gdes[i].start = im->gdes[ii].start;
844                 im->gdes[i].end = im->gdes[ii].end;
845                 im->gdes[i].step = im->gdes[ii].step;
846                 im->gdes[i].ds_cnt = im->gdes[ii].ds_cnt;
847                 im->gdes[i].ds_namv = im->gdes[ii].ds_namv;
848                 im->gdes[i].data = im->gdes[ii].data;
849                 im->gdes[i].data_first = 0;
850                 skip = 1;
851             }
852             if (skip)
853                 break;
854         }
855         if (!skip) {
856             unsigned long ft_step = im->gdes[i].step;   /* ft_step will record what we got from fetch */
857             const char *rrd_daemon;
858             int status;
859
860             if (im->gdes[i].daemon[0] != 0)
861                 rrd_daemon = im->gdes[i].daemon;
862             else
863                 rrd_daemon = im->daemon_addr;
864
865             /* "daemon" may be NULL. ENV_RRDCACHED_ADDRESS is evaluated in that
866              * case. If "daemon" holds the same value as in the previous
867              * iteration, no actual new connection is established - the
868              * existing connection is re-used. */
869             rrdc_connect (rrd_daemon);
870
871             /* If connecting was successfull, use the daemon to query the data.
872              * If there is no connection, for example because no daemon address
873              * was specified, (try to) use the local file directly. */
874             if (rrdc_is_connected (rrd_daemon))
875             {
876                 status = rrdc_fetch (im->gdes[i].rrd,
877                         cf_to_string (im->gdes[i].cf),
878                         &im->gdes[i].start,
879                         &im->gdes[i].end,
880                         &ft_step,
881                         &im->gdes[i].ds_cnt,
882                         &im->gdes[i].ds_namv,
883                         &im->gdes[i].data);
884                 if (status != 0)
885                     return (status);
886             }
887             else
888             {
889                 if ((rrd_fetch_fn(im->gdes[i].rrd,
890                                 im->gdes[i].cf,
891                                 &im->gdes[i].start,
892                                 &im->gdes[i].end,
893                                 &ft_step,
894                                 &im->gdes[i].ds_cnt,
895                                 &im->gdes[i].ds_namv,
896                                 &im->gdes[i].data)) == -1) {
897                     return -1;
898                 }
899             }
900             im->gdes[i].data_first = 1;
901
902             if (ft_step < im->gdes[i].step) {
903                 reduce_data(im->gdes[i].cf_reduce,
904                             ft_step,
905                             &im->gdes[i].start,
906                             &im->gdes[i].end,
907                             &im->gdes[i].step,
908                             &im->gdes[i].ds_cnt, &im->gdes[i].data);
909             } else {
910                 im->gdes[i].step = ft_step;
911             }
912         }
913
914         /* lets see if the required data source is really there */
915         for (ii = 0; ii < (int) im->gdes[i].ds_cnt; ii++) {
916             if (strcmp(im->gdes[i].ds_namv[ii], im->gdes[i].ds_nam) == 0) {
917                 im->gdes[i].ds = ii;
918             }
919         }
920         if (im->gdes[i].ds == -1) {
921             rrd_set_error("No DS called '%s' in '%s'",
922                           im->gdes[i].ds_nam, im->gdes[i].rrd);
923             return -1;
924         }
925
926     }
927     return 0;
928 }
929
930 /* evaluate the expressions in the CDEF functions */
931
932 /*************************************************************
933  * CDEF stuff
934  *************************************************************/
935
936 long find_var_wrapper(
937     void *arg1,
938     char *key)
939 {
940     return find_var((image_desc_t *) arg1, key);
941 }
942
943 /* find gdes containing var*/
944 long find_var(
945     image_desc_t *im,
946     char *key)
947 {
948     long      ii;
949
950     for (ii = 0; ii < im->gdes_c - 1; ii++) {
951         if ((im->gdes[ii].gf == GF_DEF
952              || im->gdes[ii].gf == GF_VDEF || im->gdes[ii].gf == GF_CDEF)
953             && (strcmp(im->gdes[ii].vname, key) == 0)) {
954             return ii;
955         }
956     }
957     return -1;
958 }
959
960 /* find the greatest common divisor for all the numbers
961    in the 0 terminated num array */
962 long lcd(
963     long *num)
964 {
965     long      rest;
966     int       i;
967
968     for (i = 0; num[i + 1] != 0; i++) {
969         do {
970             rest = num[i] % num[i + 1];
971             num[i] = num[i + 1];
972             num[i + 1] = rest;
973         } while (rest != 0);
974         num[i + 1] = num[i];
975     }
976 /*    return i==0?num[i]:num[i-1]; */
977     return num[i];
978 }
979
980 /* run the rpn calculator on all the VDEF and CDEF arguments */
981 int data_calc(
982     image_desc_t *im)
983 {
984
985     int       gdi;
986     int       dataidx;
987     long     *steparray, rpi;
988     int       stepcnt;
989     time_t    now;
990     rpnstack_t rpnstack;
991
992     rpnstack_init(&rpnstack);
993
994     for (gdi = 0; gdi < im->gdes_c; gdi++) {
995         /* Look for GF_VDEF and GF_CDEF in the same loop,
996          * so CDEFs can use VDEFs and vice versa
997          */
998         switch (im->gdes[gdi].gf) {
999         case GF_XPORT:
1000             break;
1001         case GF_SHIFT:{
1002             graph_desc_t *vdp = &im->gdes[im->gdes[gdi].vidx];
1003
1004             /* remove current shift */
1005             vdp->start -= vdp->shift;
1006             vdp->end -= vdp->shift;
1007
1008             /* vdef */
1009             if (im->gdes[gdi].shidx >= 0)
1010                 vdp->shift = im->gdes[im->gdes[gdi].shidx].vf.val;
1011             /* constant */
1012             else
1013                 vdp->shift = im->gdes[gdi].shval;
1014
1015             /* normalize shift to multiple of consolidated step */
1016             vdp->shift = (vdp->shift / (long) vdp->step) * (long) vdp->step;
1017
1018             /* apply shift */
1019             vdp->start += vdp->shift;
1020             vdp->end += vdp->shift;
1021             break;
1022         }
1023         case GF_VDEF:
1024             /* A VDEF has no DS.  This also signals other parts
1025              * of rrdtool that this is a VDEF value, not a CDEF.
1026              */
1027             im->gdes[gdi].ds_cnt = 0;
1028             if (vdef_calc(im, gdi)) {
1029                 rrd_set_error("Error processing VDEF '%s'",
1030                               im->gdes[gdi].vname);
1031                 rpnstack_free(&rpnstack);
1032                 return -1;
1033             }
1034             break;
1035         case GF_CDEF:
1036             im->gdes[gdi].ds_cnt = 1;
1037             im->gdes[gdi].ds = 0;
1038             im->gdes[gdi].data_first = 1;
1039             im->gdes[gdi].start = 0;
1040             im->gdes[gdi].end = 0;
1041             steparray = NULL;
1042             stepcnt = 0;
1043             dataidx = -1;
1044
1045             /* Find the variables in the expression.
1046              * - VDEF variables are substituted by their values
1047              *   and the opcode is changed into OP_NUMBER.
1048              * - CDEF variables are analized for their step size,
1049              *   the lowest common denominator of all the step
1050              *   sizes of the data sources involved is calculated
1051              *   and the resulting number is the step size for the
1052              *   resulting data source.
1053              */
1054             for (rpi = 0; im->gdes[gdi].rpnp[rpi].op != OP_END; rpi++) {
1055                 if (im->gdes[gdi].rpnp[rpi].op == OP_VARIABLE ||
1056                     im->gdes[gdi].rpnp[rpi].op == OP_PREV_OTHER) {
1057                     long      ptr = im->gdes[gdi].rpnp[rpi].ptr;
1058
1059                     if (im->gdes[ptr].ds_cnt == 0) {    /* this is a VDEF data source */
1060 #if 0
1061                         printf
1062                             ("DEBUG: inside CDEF '%s' processing VDEF '%s'\n",
1063                              im->gdes[gdi].vname, im->gdes[ptr].vname);
1064                         printf("DEBUG: value from vdef is %f\n",
1065                                im->gdes[ptr].vf.val);
1066 #endif
1067                         im->gdes[gdi].rpnp[rpi].val = im->gdes[ptr].vf.val;
1068                         im->gdes[gdi].rpnp[rpi].op = OP_NUMBER;
1069                     } else {    /* normal variables and PREF(variables) */
1070
1071                         /* add one entry to the array that keeps track of the step sizes of the
1072                          * data sources going into the CDEF. */
1073                         if ((steparray =
1074                              (long*)rrd_realloc(steparray,
1075                                          (++stepcnt +
1076                                           1) * sizeof(*steparray))) == NULL) {
1077                             rrd_set_error("realloc steparray");
1078                             rpnstack_free(&rpnstack);
1079                             return -1;
1080                         };
1081
1082                         steparray[stepcnt - 1] = im->gdes[ptr].step;
1083
1084                         /* adjust start and end of cdef (gdi) so
1085                          * that it runs from the latest start point
1086                          * to the earliest endpoint of any of the
1087                          * rras involved (ptr)
1088                          */
1089
1090                         if (im->gdes[gdi].start < im->gdes[ptr].start)
1091                             im->gdes[gdi].start = im->gdes[ptr].start;
1092
1093                         if (im->gdes[gdi].end == 0 ||
1094                             im->gdes[gdi].end > im->gdes[ptr].end)
1095                             im->gdes[gdi].end = im->gdes[ptr].end;
1096
1097                         /* store pointer to the first element of
1098                          * the rra providing data for variable,
1099                          * further save step size and data source
1100                          * count of this rra
1101                          */
1102                         im->gdes[gdi].rpnp[rpi].data =
1103                             im->gdes[ptr].data + im->gdes[ptr].ds;
1104                         im->gdes[gdi].rpnp[rpi].step = im->gdes[ptr].step;
1105                         im->gdes[gdi].rpnp[rpi].ds_cnt = im->gdes[ptr].ds_cnt;
1106
1107                         /* backoff the *.data ptr; this is done so
1108                          * rpncalc() function doesn't have to treat
1109                          * the first case differently
1110                          */
1111                     }   /* if ds_cnt != 0 */
1112                 }       /* if OP_VARIABLE */
1113             }           /* loop through all rpi */
1114
1115             /* move the data pointers to the correct period */
1116             for (rpi = 0; im->gdes[gdi].rpnp[rpi].op != OP_END; rpi++) {
1117                 if (im->gdes[gdi].rpnp[rpi].op == OP_VARIABLE ||
1118                     im->gdes[gdi].rpnp[rpi].op == OP_PREV_OTHER) {
1119                     long      ptr = im->gdes[gdi].rpnp[rpi].ptr;
1120                     long      diff =
1121                         im->gdes[gdi].start - im->gdes[ptr].start;
1122
1123                     if (diff > 0)
1124                         im->gdes[gdi].rpnp[rpi].data +=
1125                             (diff / im->gdes[ptr].step) *
1126                             im->gdes[ptr].ds_cnt;
1127                 }
1128             }
1129
1130             if (steparray == NULL) {
1131                 rrd_set_error("rpn expressions without DEF"
1132                               " or CDEF variables are not supported");
1133                 rpnstack_free(&rpnstack);
1134                 return -1;
1135             }
1136             steparray[stepcnt] = 0;
1137             /* Now find the resulting step.  All steps in all
1138              * used RRAs have to be visited
1139              */
1140             im->gdes[gdi].step = lcd(steparray);
1141             free(steparray);
1142             if ((im->gdes[gdi].data = (rrd_value_t*)malloc(((im->gdes[gdi].end -
1143                                                im->gdes[gdi].start)
1144                                               / im->gdes[gdi].step)
1145                                              * sizeof(double))) == NULL) {
1146                 rrd_set_error("malloc im->gdes[gdi].data");
1147                 rpnstack_free(&rpnstack);
1148                 return -1;
1149             }
1150
1151             /* Step through the new cdef results array and
1152              * calculate the values
1153              */
1154             for (now = im->gdes[gdi].start + im->gdes[gdi].step;
1155                  now <= im->gdes[gdi].end; now += im->gdes[gdi].step) {
1156                 rpnp_t   *rpnp = im->gdes[gdi].rpnp;
1157
1158                 /* 3rd arg of rpn_calc is for OP_VARIABLE lookups;
1159                  * in this case we are advancing by timesteps;
1160                  * we use the fact that time_t is a synonym for long
1161                  */
1162                 if (rpn_calc(rpnp, &rpnstack, (long) now,
1163                              im->gdes[gdi].data, ++dataidx) == -1) {
1164                     /* rpn_calc sets the error string */
1165                     rpnstack_free(&rpnstack);
1166                     return -1;
1167                 }
1168             }           /* enumerate over time steps within a CDEF */
1169             break;
1170         default:
1171             continue;
1172         }
1173     }                   /* enumerate over CDEFs */
1174     rpnstack_free(&rpnstack);
1175     return 0;
1176 }
1177
1178 /* from http://www.cygnus-software.com/papers/comparingfloats/comparingfloats.htm */
1179 /* yes we are loosing precision by doing tos with floats instead of doubles
1180    but it seems more stable this way. */
1181
1182 static int AlmostEqual2sComplement(
1183     float A,
1184     float B,
1185     int maxUlps)
1186 {
1187
1188     int       aInt = *(int *) &A;
1189     int       bInt = *(int *) &B;
1190     int       intDiff;
1191
1192     /* Make sure maxUlps is non-negative and small enough that the
1193        default NAN won't compare as equal to anything.  */
1194
1195     /* assert(maxUlps > 0 && maxUlps < 4 * 1024 * 1024); */
1196
1197     /* Make aInt lexicographically ordered as a twos-complement int */
1198
1199     if (aInt < 0)
1200         aInt = 0x80000000l - aInt;
1201
1202     /* Make bInt lexicographically ordered as a twos-complement int */
1203
1204     if (bInt < 0)
1205         bInt = 0x80000000l - bInt;
1206
1207     intDiff = abs(aInt - bInt);
1208
1209     if (intDiff <= maxUlps)
1210         return 1;
1211
1212     return 0;
1213 }
1214
1215 /* massage data so, that we get one value for each x coordinate in the graph */
1216 int data_proc(
1217     image_desc_t *im)
1218 {
1219     long      i, ii;
1220     double    pixstep = (double) (im->end - im->start)
1221         / (double) im->xsize;   /* how much time
1222                                    passes in one pixel */
1223     double    paintval;
1224     double    minval = DNAN, maxval = DNAN;
1225
1226     unsigned long gr_time;
1227
1228     /* memory for the processed data */
1229     for (i = 0; i < im->gdes_c; i++) {
1230         if ((im->gdes[i].gf == GF_LINE)
1231          || (im->gdes[i].gf == GF_AREA) 
1232          || (im->gdes[i].gf == GF_TICK)
1233          || (im->gdes[i].gf == GF_GRAD)
1234         ) {
1235             if ((im->gdes[i].p_data = (rrd_value_t*)malloc((im->xsize + 1)
1236                                              * sizeof(rrd_value_t))) == NULL) {
1237                 rrd_set_error("malloc data_proc");
1238                 return -1;
1239             }
1240         }
1241     }
1242
1243     for (i = 0; i < im->xsize; i++) {   /* for each pixel */
1244         long      vidx;
1245
1246         gr_time = im->start + pixstep * i;  /* time of the current step */
1247         paintval = 0.0;
1248
1249         for (ii = 0; ii < im->gdes_c; ii++) {
1250             double    value;
1251
1252             switch (im->gdes[ii].gf) {
1253             case GF_LINE:
1254             case GF_AREA:
1255                         case GF_GRAD:
1256             case GF_TICK:
1257                 if (!im->gdes[ii].stack)
1258                     paintval = 0.0;
1259                 value = im->gdes[ii].yrule;
1260                 if (isnan(value) || (im->gdes[ii].gf == GF_TICK)) {
1261                     /* The time of the data doesn't necessarily match
1262                      ** the time of the graph. Beware.
1263                      */
1264                     vidx = im->gdes[ii].vidx;
1265                     if (im->gdes[vidx].gf == GF_VDEF) {
1266                         value = im->gdes[vidx].vf.val;
1267                     } else
1268                         if (((long int) gr_time >=
1269                              (long int) im->gdes[vidx].start)
1270                             && ((long int) gr_time <
1271                                 (long int) im->gdes[vidx].end)) {
1272                         value = im->gdes[vidx].data[(unsigned long)
1273                                                     floor((double)
1274                                                           (gr_time -
1275                                                            im->gdes[vidx].
1276                                                            start)
1277                                                           /
1278                                                           im->gdes[vidx].step)
1279                                                     * im->gdes[vidx].ds_cnt +
1280                                                     im->gdes[vidx].ds];
1281                     } else {
1282                         value = DNAN;
1283                     }
1284                 };
1285
1286                 if (!isnan(value)) {
1287                     paintval += value;
1288                     im->gdes[ii].p_data[i] = paintval;
1289                     /* GF_TICK: the data values are not
1290                      ** relevant for min and max
1291                      */
1292                     if (finite(paintval) && im->gdes[ii].gf != GF_TICK) {
1293                         if ((isnan(minval) || paintval < minval) &&
1294                             !(im->logarithmic && paintval <= 0.0))
1295                             minval = paintval;
1296                         if (isnan(maxval) || paintval > maxval)
1297                             maxval = paintval;
1298                     }
1299                 } else {
1300                     im->gdes[ii].p_data[i] = DNAN;
1301                 }
1302                 break;
1303             case GF_STACK:
1304                 rrd_set_error
1305                     ("STACK should already be turned into LINE or AREA here");
1306                 return -1;
1307                 break;
1308             default:
1309                 break;
1310             }
1311         }
1312     }
1313
1314     /* if min or max have not been asigned a value this is because
1315        there was no data in the graph ... this is not good ...
1316        lets set these to dummy values then ... */
1317
1318     if (im->logarithmic) {
1319         if (isnan(minval) || isnan(maxval) || maxval <= 0) {
1320             minval = 0.0;   /* catching this right away below */
1321             maxval = 5.1;
1322         }
1323         /* in logarithm mode, where minval is smaller or equal
1324            to 0 make the beast just way smaller than maxval */
1325         if (minval <= 0) {
1326             minval = maxval / 10e8;
1327         }
1328     } else {
1329         if (isnan(minval) || isnan(maxval)) {
1330             minval = 0.0;
1331             maxval = 1.0;
1332         }
1333     }
1334
1335     /* adjust min and max values given by the user */
1336     /* for logscale we add something on top */
1337     if (isnan(im->minval)
1338         || ((!im->rigid) && im->minval > minval)
1339         ) {
1340         if (im->logarithmic)
1341             im->minval = minval / 2.0;
1342         else
1343             im->minval = minval;
1344     }
1345     if (isnan(im->maxval)
1346         || (!im->rigid && im->maxval < maxval)
1347         ) {
1348         if (im->logarithmic)
1349             im->maxval = maxval * 2.0;
1350         else
1351             im->maxval = maxval;
1352     }
1353
1354     /* make sure min is smaller than max */
1355     if (im->minval > im->maxval) {
1356         if (im->minval > 0)
1357             im->minval = 0.99 * im->maxval;
1358         else
1359             im->minval = 1.01 * im->maxval;
1360     }
1361
1362     /* make sure min and max are not equal */
1363     if (AlmostEqual2sComplement(im->minval, im->maxval, 4)) {
1364         if (im->maxval > 0)
1365             im->maxval *= 1.01;
1366         else
1367             im->maxval *= 0.99;
1368
1369         /* make sure min and max are not both zero */
1370         if (AlmostEqual2sComplement(im->maxval, 0, 4)) {
1371             im->maxval = 1.0;
1372         }
1373     }
1374     return 0;
1375 }
1376
1377 static int find_first_weekday(void){
1378     static int first_weekday = -1;
1379     if (first_weekday == -1){
1380 #ifdef HAVE__NL_TIME_WEEK_1STDAY
1381         /* according to http://sourceware.org/ml/libc-locales/2009-q1/msg00011.html */
1382         long week_1stday_l = (long) nl_langinfo (_NL_TIME_WEEK_1STDAY);
1383         if (week_1stday_l == 19971130) first_weekday = 0; /* Sun */
1384         else if (week_1stday_l == 19971201) first_weekday = 1; /* Mon */
1385         else first_weekday = 1; /* we go for a monday default */
1386 #else
1387         first_weekday = 1;
1388 #endif
1389     }
1390     return first_weekday;
1391 }
1392
1393 /* identify the point where the first gridline, label ... gets placed */
1394
1395 time_t find_first_time(
1396     time_t start,       /* what is the initial time */
1397     enum tmt_en baseint,    /* what is the basic interval */
1398     long basestep       /* how many if these do we jump a time */
1399     )
1400 {
1401     struct tm tm;
1402
1403     localtime_r(&start, &tm);
1404
1405     switch (baseint) {
1406     case TMT_SECOND:
1407         tm.       tm_sec -= tm.tm_sec % basestep;
1408
1409         break;
1410     case TMT_MINUTE:
1411         tm.       tm_sec = 0;
1412         tm.       tm_min -= tm.tm_min % basestep;
1413
1414         break;
1415     case TMT_HOUR:
1416         tm.       tm_sec = 0;
1417         tm.       tm_min = 0;
1418         tm.       tm_hour -= tm.tm_hour % basestep;
1419
1420         break;
1421     case TMT_DAY:
1422         /* we do NOT look at the basestep for this ... */
1423         tm.       tm_sec = 0;
1424         tm.       tm_min = 0;
1425         tm.       tm_hour = 0;
1426
1427         break;
1428     case TMT_WEEK:
1429         /* we do NOT look at the basestep for this ... */
1430         tm.       tm_sec = 0;
1431         tm.       tm_min = 0;
1432         tm.       tm_hour = 0;
1433         tm.       tm_mday -= tm.tm_wday - find_first_weekday();
1434
1435         if (tm.tm_wday == 0 && find_first_weekday() > 0)
1436             tm.       tm_mday -= 7; /* we want the *previous* week */
1437
1438         break;
1439     case TMT_MONTH:
1440         tm.       tm_sec = 0;
1441         tm.       tm_min = 0;
1442         tm.       tm_hour = 0;
1443         tm.       tm_mday = 1;
1444         tm.       tm_mon -= tm.tm_mon % basestep;
1445
1446         break;
1447
1448     case TMT_YEAR:
1449         tm.       tm_sec = 0;
1450         tm.       tm_min = 0;
1451         tm.       tm_hour = 0;
1452         tm.       tm_mday = 1;
1453         tm.       tm_mon = 0;
1454         tm.       tm_year -= (
1455     tm.tm_year + 1900) %basestep;
1456
1457     }
1458     return mktime(&tm);
1459 }
1460
1461 /* identify the point where the next gridline, label ... gets placed */
1462 time_t find_next_time(
1463     time_t current,     /* what is the initial time */
1464     enum tmt_en baseint,    /* what is the basic interval */
1465     long basestep       /* how many if these do we jump a time */
1466     )
1467 {
1468     struct tm tm;
1469     time_t    madetime;
1470
1471     localtime_r(&current, &tm);
1472
1473     int limit = 2;
1474     switch (baseint) {
1475     case TMT_SECOND: limit = 7200; break;
1476     case TMT_MINUTE: limit = 120; break;
1477     case TMT_HOUR: limit = 2; break;
1478     default: limit = 2; break;
1479     }
1480     do {
1481         switch (baseint) {
1482         case TMT_SECOND:
1483             tm.       tm_sec += basestep;
1484
1485             break;
1486         case TMT_MINUTE:
1487             tm.       tm_min += basestep;
1488
1489             break;
1490         case TMT_HOUR:
1491             tm.       tm_hour += basestep;
1492
1493             break;
1494         case TMT_DAY:
1495             tm.       tm_mday += basestep;
1496
1497             break;
1498         case TMT_WEEK:
1499             tm.       tm_mday += 7 * basestep;
1500
1501             break;
1502         case TMT_MONTH:
1503             tm.       tm_mon += basestep;
1504
1505             break;
1506         case TMT_YEAR:
1507             tm.       tm_year += basestep;
1508         }
1509         madetime = mktime(&tm);
1510     } while (madetime == -1 && limit-- >= 0);   /* this is necessary to skip impossible times
1511                                    like the daylight saving time skips */
1512     return madetime;
1513
1514 }
1515
1516
1517 /* calculate values required for PRINT and GPRINT functions */
1518
1519 int print_calc(
1520     image_desc_t *im)
1521 {
1522     long      i, ii, validsteps;
1523     double    printval;
1524     struct tm tmvdef;
1525     int       graphelement = 0;
1526     long      vidx;
1527     int       max_ii;
1528     double    magfact = -1;
1529     char     *si_symb = "";
1530     char     *percent_s;
1531     int       prline_cnt = 0;
1532
1533     /* wow initializing tmvdef is quite a task :-) */
1534     time_t    now = time(NULL);
1535
1536     localtime_r(&now, &tmvdef);
1537     for (i = 0; i < im->gdes_c; i++) {
1538         vidx = im->gdes[i].vidx;
1539         switch (im->gdes[i].gf) {
1540         case GF_PRINT:
1541         case GF_GPRINT:
1542             /* PRINT and GPRINT can now print VDEF generated values.
1543              * There's no need to do any calculations on them as these
1544              * calculations were already made.
1545              */
1546             if (im->gdes[vidx].gf == GF_VDEF) { /* simply use vals */
1547                 printval = im->gdes[vidx].vf.val;
1548                 localtime_r(&im->gdes[vidx].vf.when, &tmvdef);
1549             } else {    /* need to calculate max,min,avg etcetera */
1550                 max_ii = ((im->gdes[vidx].end - im->gdes[vidx].start)
1551                           / im->gdes[vidx].step * im->gdes[vidx].ds_cnt);
1552                 printval = DNAN;
1553                 validsteps = 0;
1554                 for (ii = im->gdes[vidx].ds;
1555                      ii < max_ii; ii += im->gdes[vidx].ds_cnt) {
1556                     if (!finite(im->gdes[vidx].data[ii]))
1557                         continue;
1558                     if (isnan(printval)) {
1559                         printval = im->gdes[vidx].data[ii];
1560                         validsteps++;
1561                         continue;
1562                     }
1563
1564                     switch (im->gdes[i].cf) {
1565                     case CF_HWPREDICT:
1566                     case CF_MHWPREDICT:
1567                     case CF_DEVPREDICT:
1568                     case CF_DEVSEASONAL:
1569                     case CF_SEASONAL:
1570                     case CF_AVERAGE:
1571                         validsteps++;
1572                         printval += im->gdes[vidx].data[ii];
1573                         break;
1574                     case CF_MINIMUM:
1575                         printval = min(printval, im->gdes[vidx].data[ii]);
1576                         break;
1577                     case CF_FAILURES:
1578                     case CF_MAXIMUM:
1579                         printval = max(printval, im->gdes[vidx].data[ii]);
1580                         break;
1581                     case CF_LAST:
1582                         printval = im->gdes[vidx].data[ii];
1583                     }
1584                 }
1585                 if (im->gdes[i].cf == CF_AVERAGE || im->gdes[i].cf > CF_LAST) {
1586                     if (validsteps > 1) {
1587                         printval = (printval / validsteps);
1588                     }
1589                 }
1590             }           /* prepare printval */
1591
1592             if (!im->gdes[i].strftm && (percent_s = strstr(im->gdes[i].format, "%S")) != NULL) {
1593                 /* Magfact is set to -1 upon entry to print_calc.  If it
1594                  * is still less than 0, then we need to run auto_scale.
1595                  * Otherwise, put the value into the correct units.  If
1596                  * the value is 0, then do not set the symbol or magnification
1597                  * so next the calculation will be performed again. */
1598                 if (magfact < 0.0) {
1599                     auto_scale(im, &printval, &si_symb, &magfact);
1600                     if (printval == 0.0)
1601                         magfact = -1.0;
1602                 } else {
1603                     printval /= magfact;
1604                 }
1605                 *(++percent_s) = 's';
1606             } else if (!im->gdes[i].strftm && strstr(im->gdes[i].format, "%s") != NULL) {
1607                 auto_scale(im, &printval, &si_symb, &magfact);
1608             }
1609
1610             if (im->gdes[i].gf == GF_PRINT) {
1611                 rrd_infoval_t prline;
1612
1613                 if (im->gdes[i].strftm) {
1614                     prline.u_str = (char*)malloc((FMT_LEG_LEN + 2) * sizeof(char));
1615                     if (im->gdes[vidx].vf.never == 1) {
1616                        time_clean(prline.u_str, im->gdes[i].format);
1617                     } else {
1618                         strftime(prline.u_str,
1619                                  FMT_LEG_LEN, im->gdes[i].format, &tmvdef);
1620                     }
1621                 } else if (bad_format(im->gdes[i].format)) {
1622                     rrd_set_error
1623                         ("bad format for PRINT in '%s'", im->gdes[i].format);
1624                     return -1;
1625                 } else {
1626                     prline.u_str =
1627                         sprintf_alloc(im->gdes[i].format, printval, si_symb);
1628                 }
1629                 grinfo_push(im,
1630                             sprintf_alloc
1631                             ("print[%ld]", prline_cnt++), RD_I_STR, prline);
1632                 free(prline.u_str);
1633             } else {
1634                 /* GF_GPRINT */
1635
1636                 if (im->gdes[i].strftm) {
1637                     if (im->gdes[vidx].vf.never == 1) {
1638                        time_clean(im->gdes[i].legend, im->gdes[i].format);
1639                     } else {
1640                         strftime(im->gdes[i].legend,
1641                                  FMT_LEG_LEN, im->gdes[i].format, &tmvdef);
1642                     }
1643                 } else {
1644                     if (bad_format(im->gdes[i].format)) {
1645                         rrd_set_error
1646                             ("bad format for GPRINT in '%s'",
1647                              im->gdes[i].format);
1648                         return -1;
1649                     }
1650 #ifdef HAVE_SNPRINTF
1651                     snprintf(im->gdes[i].legend,
1652                              FMT_LEG_LEN - 2,
1653                              im->gdes[i].format, printval, si_symb);
1654 #else
1655                     sprintf(im->gdes[i].legend,
1656                             im->gdes[i].format, printval, si_symb);
1657 #endif
1658                 }
1659                 graphelement = 1;
1660             }
1661             break;
1662         case GF_LINE:
1663         case GF_AREA:
1664                 case GF_GRAD:
1665         case GF_TICK:
1666             graphelement = 1;
1667             break;
1668         case GF_HRULE:
1669             if (isnan(im->gdes[i].yrule)) { /* we must set this here or the legend printer can not decide to print the legend */
1670                 im->gdes[i].yrule = im->gdes[vidx].vf.val;
1671             };
1672             graphelement = 1;
1673             break;
1674         case GF_VRULE:
1675             if (im->gdes[i].xrule == 0) {   /* again ... the legend printer needs it */
1676                 im->gdes[i].xrule = im->gdes[vidx].vf.when;
1677             };
1678             graphelement = 1;
1679             break;
1680         case GF_COMMENT:
1681         case GF_TEXTALIGN:
1682         case GF_DEF:
1683         case GF_CDEF:
1684         case GF_VDEF:
1685 #ifdef WITH_PIECHART
1686         case GF_PART:
1687 #endif
1688         case GF_SHIFT:
1689         case GF_XPORT:
1690             break;
1691         case GF_STACK:
1692             rrd_set_error
1693                 ("STACK should already be turned into LINE or AREA here");
1694             return -1;
1695             break;
1696         }
1697     }
1698     return graphelement;
1699 }
1700
1701
1702
1703 /* place legends with color spots */
1704 int leg_place(
1705     image_desc_t *im,
1706     int calc_width)
1707 {
1708     /* graph labels */
1709     int       interleg = im->text_prop[TEXT_PROP_LEGEND].size * 2.0;
1710     int       border = im->text_prop[TEXT_PROP_LEGEND].size * 2.0;
1711     int       fill = 0, fill_last;
1712     double    legendwidth; // = im->ximg - 2 * border;
1713     int       leg_c = 0;
1714     double    leg_x = border;
1715     int       leg_y = 0; //im->yimg;
1716     int       leg_y_prev = 0; // im->yimg;
1717     int       leg_cc;
1718     double    glue = 0;
1719     int       i, ii, mark = 0;
1720     char      default_txtalign = TXA_JUSTIFIED; /*default line orientation */
1721     int      *legspace;
1722     char     *tab;
1723     char      saved_legend[FMT_LEG_LEN + 5];
1724
1725     if(calc_width){
1726         legendwidth = 0;
1727     }
1728     else{
1729         legendwidth = im->legendwidth - 2 * border;
1730     }
1731
1732
1733     if (!(im->extra_flags & NOLEGEND) && !(im->extra_flags & ONLY_GRAPH)) {
1734         if ((legspace = (int*)malloc(im->gdes_c * sizeof(int))) == NULL) {
1735             rrd_set_error("malloc for legspace");
1736             return -1;
1737         }
1738
1739         for (i = 0; i < im->gdes_c; i++) {
1740             char      prt_fctn; /*special printfunctions */
1741             if(calc_width){
1742                 strcpy(saved_legend, im->gdes[i].legend);
1743             }
1744
1745             fill_last = fill;
1746             /* hide legends for rules which are not displayed */
1747             if (im->gdes[i].gf == GF_TEXTALIGN) {
1748                 default_txtalign = im->gdes[i].txtalign;
1749             }
1750
1751             if (!(im->extra_flags & FORCE_RULES_LEGEND)) {
1752                 if (im->gdes[i].gf == GF_HRULE
1753                     && (im->gdes[i].yrule <
1754                         im->minval || im->gdes[i].yrule > im->maxval))
1755                     im->gdes[i].legend[0] = '\0';
1756                 if (im->gdes[i].gf == GF_VRULE
1757                     && (im->gdes[i].xrule <
1758                         im->start || im->gdes[i].xrule > im->end))
1759                     im->gdes[i].legend[0] = '\0';
1760             }
1761
1762             /* turn \\t into tab */
1763             while ((tab = strstr(im->gdes[i].legend, "\\t"))) {
1764                 memmove(tab, tab + 1, strlen(tab));
1765                 tab[0] = (char) 9;
1766             }
1767
1768             leg_cc = strlen(im->gdes[i].legend);
1769             /* is there a controle code at the end of the legend string ? */
1770             if (leg_cc >= 2 && im->gdes[i].legend[leg_cc - 2] == '\\') {
1771                 prt_fctn = im->gdes[i].legend[leg_cc - 1];
1772                 leg_cc -= 2;
1773                 im->gdes[i].legend[leg_cc] = '\0';
1774             } else {
1775                 prt_fctn = '\0';
1776             }
1777             /* only valid control codes */
1778             if (prt_fctn != 'l' && prt_fctn != 'n' &&   /* a synonym for l */
1779                 prt_fctn != 'r' &&
1780                 prt_fctn != 'j' &&
1781                 prt_fctn != 'c' &&
1782                 prt_fctn != 'u' &&
1783                 prt_fctn != 's' && prt_fctn != '\0' && prt_fctn != 'g') {
1784                 free(legspace);
1785                 rrd_set_error
1786                     ("Unknown control code at the end of '%s\\%c'",
1787                      im->gdes[i].legend, prt_fctn);
1788                 return -1;
1789             }
1790             /* \n -> \l */
1791             if (prt_fctn == 'n') {
1792                 prt_fctn = 'l';
1793             }
1794
1795             /* remove exess space from the end of the legend for \g */
1796             while (prt_fctn == 'g' &&
1797                    leg_cc > 0 && im->gdes[i].legend[leg_cc - 1] == ' ') {
1798                 leg_cc--;
1799                 im->gdes[i].legend[leg_cc] = '\0';
1800             }
1801
1802             if (leg_cc != 0) {
1803
1804                 /* no interleg space if string ends in \g */
1805                 legspace[i] = (prt_fctn == 'g' ? 0 : interleg);
1806                 if (fill > 0) {
1807                     fill += legspace[i];
1808                 }
1809                 fill +=
1810                     gfx_get_text_width(im,
1811                                        fill + border,
1812                                        im->
1813                                        text_prop
1814                                        [TEXT_PROP_LEGEND].
1815                                        font_desc,
1816                                        im->tabwidth, im->gdes[i].legend);
1817                 leg_c++;
1818             } else {
1819                 legspace[i] = 0;
1820             }
1821             /* who said there was a special tag ... ? */
1822             if (prt_fctn == 'g') {
1823                 prt_fctn = '\0';
1824             }
1825
1826             if (prt_fctn == '\0') {
1827                 if(calc_width && (fill > legendwidth)){
1828                     legendwidth = fill;
1829                 }
1830                 if (i == im->gdes_c - 1 || fill > legendwidth) {
1831                     /* just one legend item is left right or center */
1832                     switch (default_txtalign) {
1833                     case TXA_RIGHT:
1834                         prt_fctn = 'r';
1835                         break;
1836                     case TXA_CENTER:
1837                         prt_fctn = 'c';
1838                         break;
1839                     case TXA_JUSTIFIED:
1840                         prt_fctn = 'j';
1841                         break;
1842                     default:
1843                         prt_fctn = 'l';
1844                         break;
1845                     }
1846                 }
1847                 /* is it time to place the legends ? */
1848                 if (fill > legendwidth) {
1849                     if (leg_c > 1) {
1850                         /* go back one */
1851                         i--;
1852                         fill = fill_last;
1853                         leg_c--;
1854                     }
1855                 }
1856                 if (leg_c == 1 && prt_fctn == 'j') {
1857                     prt_fctn = 'l';
1858                 }
1859             }
1860
1861             if (prt_fctn != '\0') {
1862                 leg_x = border;
1863                 if (leg_c >= 2 && prt_fctn == 'j') {
1864                     glue = (double)(legendwidth - fill) / (double)(leg_c - 1);
1865                 } else {
1866                     glue = 0;
1867                 }
1868                 if (prt_fctn == 'c')
1869                     leg_x = border + (double)(legendwidth - fill) / 2.0;
1870                 if (prt_fctn == 'r')
1871                     leg_x = legendwidth - fill + border;
1872                 for (ii = mark; ii <= i; ii++) {
1873                     if (im->gdes[ii].legend[0] == '\0')
1874                         continue;   /* skip empty legends */
1875                     im->gdes[ii].leg_x = leg_x;
1876                     im->gdes[ii].leg_y = leg_y + border;
1877                     leg_x +=
1878                         (double)gfx_get_text_width(im, leg_x,
1879                                            im->
1880                                            text_prop
1881                                            [TEXT_PROP_LEGEND].
1882                                            font_desc,
1883                                            im->tabwidth, im->gdes[ii].legend)
1884                         +(double)legspace[ii]
1885                         + glue;
1886                 }
1887                 leg_y_prev = leg_y;
1888                 if (leg_x > border || prt_fctn == 's')
1889                     leg_y += im->text_prop[TEXT_PROP_LEGEND].size * 1.8;
1890                 if (prt_fctn == 's')
1891                     leg_y -= im->text_prop[TEXT_PROP_LEGEND].size;
1892                 if (prt_fctn == 'u')
1893                     leg_y -= im->text_prop[TEXT_PROP_LEGEND].size *1.8;
1894
1895                 if(calc_width && (fill > legendwidth)){
1896                     legendwidth = fill;
1897                 }
1898                 fill = 0;
1899                 leg_c = 0;
1900                 mark = ii;
1901             }
1902
1903             if(calc_width){
1904                 strcpy(im->gdes[i].legend, saved_legend);
1905             }
1906         }
1907
1908         if(calc_width){
1909             im->legendwidth = legendwidth + 2 * border;
1910         }
1911         else{
1912             im->legendheight = leg_y + border * 0.6;
1913         }
1914         free(legspace);
1915     }
1916     return 0;
1917 }
1918
1919 /* create a grid on the graph. it determines what to do
1920    from the values of xsize, start and end */
1921
1922 /* the xaxis labels are determined from the number of seconds per pixel
1923    in the requested graph */
1924
1925 int calc_horizontal_grid(
1926     image_desc_t
1927     *im)
1928 {
1929     double    range;
1930     double    scaledrange;
1931     int       pixel, i;
1932     int       gridind = 0;
1933     int       decimals, fractionals;
1934
1935     im->ygrid_scale.labfact = 2;
1936     range = im->maxval - im->minval;
1937     scaledrange = range / im->magfact;
1938     /* does the scale of this graph make it impossible to put lines
1939        on it? If so, give up. */
1940     if (isnan(scaledrange)) {
1941         return 0;
1942     }
1943
1944     /* find grid spaceing */
1945     pixel = 1;
1946     if (isnan(im->ygridstep)) {
1947         if (im->extra_flags & ALTYGRID) {
1948             /* find the value with max number of digits. Get number of digits */
1949             decimals =
1950                 ceil(log10
1951                      (max(fabs(im->maxval), fabs(im->minval)) *
1952                       im->viewfactor / im->magfact));
1953             if (decimals <= 0)  /* everything is small. make place for zero */
1954                 decimals = 1;
1955             im->ygrid_scale.gridstep =
1956                 pow((double) 10,
1957                     floor(log10(range * im->viewfactor / im->magfact))) /
1958                 im->viewfactor * im->magfact;
1959             if (im->ygrid_scale.gridstep == 0)  /* range is one -> 0.1 is reasonable scale */
1960                 im->ygrid_scale.gridstep = 0.1;
1961             /* should have at least 5 lines but no more then 15 */
1962             if (range / im->ygrid_scale.gridstep < 5
1963                 && im->ygrid_scale.gridstep >= 30)
1964                 im->ygrid_scale.gridstep /= 10;
1965             if (range / im->ygrid_scale.gridstep > 15)
1966                 im->ygrid_scale.gridstep *= 10;
1967             if (range / im->ygrid_scale.gridstep > 5) {
1968                 im->ygrid_scale.labfact = 1;
1969                 if (range / im->ygrid_scale.gridstep > 8
1970                     || im->ygrid_scale.gridstep <
1971                     1.8 * im->text_prop[TEXT_PROP_AXIS].size)
1972                     im->ygrid_scale.labfact = 2;
1973             } else {
1974                 im->ygrid_scale.gridstep /= 5;
1975                 im->ygrid_scale.labfact = 5;
1976             }
1977             fractionals =
1978                 floor(log10
1979                       (im->ygrid_scale.gridstep *
1980                        (double) im->ygrid_scale.labfact * im->viewfactor /
1981                        im->magfact));
1982             if (fractionals < 0) {  /* small amplitude. */
1983                 int       len = decimals - fractionals + 1;
1984
1985                 if (im->unitslength < len + 2)
1986                     im->unitslength = len + 2;
1987                 sprintf(im->ygrid_scale.labfmt,
1988                         "%%%d.%df%s", len,
1989                         -fractionals, (im->symbol != ' ' ? " %c" : ""));
1990             } else {
1991                 int       len = decimals + 1;
1992
1993                 if (im->unitslength < len + 2)
1994                     im->unitslength = len + 2;
1995                 sprintf(im->ygrid_scale.labfmt,
1996                         "%%%d.0f%s", len, (im->symbol != ' ' ? " %c" : ""));
1997             }
1998         } else {        /* classic rrd grid */
1999             for (i = 0; ylab[i].grid > 0; i++) {
2000                 pixel = im->ysize / (scaledrange / ylab[i].grid);
2001                 gridind = i;
2002                 if (pixel >= 5)
2003                     break;
2004             }
2005
2006             for (i = 0; i < 4; i++) {
2007                 if (pixel * ylab[gridind].lfac[i] >=
2008                     1.8 * im->text_prop[TEXT_PROP_AXIS].size) {
2009                     im->ygrid_scale.labfact = ylab[gridind].lfac[i];
2010                     break;
2011                 }
2012             }
2013
2014             im->ygrid_scale.gridstep = ylab[gridind].grid * im->magfact;
2015         }
2016     } else {
2017         im->ygrid_scale.gridstep = im->ygridstep;
2018         im->ygrid_scale.labfact = im->ylabfact;
2019     }
2020     return 1;
2021 }
2022
2023 int draw_horizontal_grid(
2024     image_desc_t
2025     *im)
2026 {
2027     int       i;
2028     double    scaledstep;
2029     char      graph_label[100];
2030     int       nlabels = 0;
2031     double    X0 = im->xorigin;
2032     double    X1 = im->xorigin + im->xsize;
2033     int       sgrid = (int) (im->minval / im->ygrid_scale.gridstep - 1);
2034     int       egrid = (int) (im->maxval / im->ygrid_scale.gridstep + 1);
2035     double    MaxY;
2036     double second_axis_magfact = 0;
2037     char *second_axis_symb = "";
2038
2039     scaledstep =
2040         im->ygrid_scale.gridstep /
2041         (double) im->magfact * (double) im->viewfactor;
2042     MaxY = scaledstep * (double) egrid;
2043     for (i = sgrid; i <= egrid; i++) {
2044         double    Y0 = ytr(im,
2045                            im->ygrid_scale.gridstep * i);
2046         double    YN = ytr(im,
2047                            im->ygrid_scale.gridstep * (i + 1));
2048
2049         if (floor(Y0 + 0.5) >=
2050             im->yorigin - im->ysize && floor(Y0 + 0.5) <= im->yorigin) {
2051             /* Make sure at least 2 grid labels are shown, even if it doesn't agree
2052                with the chosen settings. Add a label if required by settings, or if
2053                there is only one label so far and the next grid line is out of bounds. */
2054             if (i % im->ygrid_scale.labfact == 0
2055                 || (nlabels == 1
2056                     && (YN < im->yorigin - im->ysize || YN > im->yorigin))) {
2057                 if (im->symbol == ' ') {
2058                     if (im->extra_flags & ALTYGRID) {
2059                         sprintf(graph_label,
2060                                 im->ygrid_scale.labfmt,
2061                                 scaledstep * (double) i);
2062                     } else {
2063                         if (MaxY < 10) {
2064                             sprintf(graph_label, "%4.1f",
2065                                     scaledstep * (double) i);
2066                         } else {
2067                             sprintf(graph_label, "%4.0f",
2068                                     scaledstep * (double) i);
2069                         }
2070                     }
2071                 } else {
2072                     char      sisym = (i == 0 ? ' ' : im->symbol);
2073
2074                     if (im->extra_flags & ALTYGRID) {
2075                         sprintf(graph_label,
2076                                 im->ygrid_scale.labfmt,
2077                                 scaledstep * (double) i, sisym);
2078                     } else {
2079                         if (MaxY < 10) {
2080                             sprintf(graph_label, "%4.1f %c",
2081                                     scaledstep * (double) i, sisym);
2082                         } else {
2083                             sprintf(graph_label, "%4.0f %c",
2084                                     scaledstep * (double) i, sisym);
2085                         }
2086                     }
2087                 }
2088                 nlabels++;
2089                 if (im->second_axis_scale != 0){
2090                         char graph_label_right[100];
2091                         double sval = im->ygrid_scale.gridstep*(double)i*im->second_axis_scale+im->second_axis_shift;
2092                         if (im->second_axis_format[0] == '\0'){
2093                             if (!second_axis_magfact){
2094                                 double dummy = im->ygrid_scale.gridstep*(double)(sgrid+egrid)/2.0*im->second_axis_scale+im->second_axis_shift;
2095                                 auto_scale(im,&dummy,&second_axis_symb,&second_axis_magfact);
2096                             }
2097                             sval /= second_axis_magfact;
2098
2099                             if(MaxY < 10) {
2100                                 sprintf(graph_label_right,"%5.1f %s",sval,second_axis_symb);
2101                             } else {
2102                                 sprintf(graph_label_right,"%5.0f %s",sval,second_axis_symb);
2103                             }
2104                         }
2105                         else {
2106                            sprintf(graph_label_right,im->second_axis_format,sval);
2107                         }
2108                         gfx_text ( im,
2109                                X1+7, Y0,
2110                                im->graph_col[GRC_FONT],
2111                                im->text_prop[TEXT_PROP_AXIS].font_desc,
2112                                im->tabwidth,0.0, GFX_H_LEFT, GFX_V_CENTER,
2113                                graph_label_right );
2114                 }
2115
2116                 gfx_text(im,
2117                          X0 -
2118                          im->
2119                          text_prop[TEXT_PROP_AXIS].
2120                          size, Y0,
2121                          im->graph_col[GRC_FONT],
2122                          im->
2123                          text_prop[TEXT_PROP_AXIS].
2124                          font_desc,
2125                          im->tabwidth, 0.0,
2126                          GFX_H_RIGHT, GFX_V_CENTER, graph_label);
2127                 gfx_line(im, X0 - 2, Y0, X0, Y0,
2128                          MGRIDWIDTH, im->graph_col[GRC_MGRID]);
2129                 gfx_line(im, X1, Y0, X1 + 2, Y0,
2130                          MGRIDWIDTH, im->graph_col[GRC_MGRID]);
2131                 gfx_dashed_line(im, X0 - 2, Y0,
2132                                 X1 + 2, Y0,
2133                                 MGRIDWIDTH,
2134                                 im->
2135                                 graph_col
2136                                 [GRC_MGRID],
2137                                 im->grid_dash_on, im->grid_dash_off);
2138             } else if (!(im->extra_flags & NOMINOR)) {
2139                 gfx_line(im,
2140                          X0 - 2, Y0,
2141                          X0, Y0, GRIDWIDTH, im->graph_col[GRC_GRID]);
2142                 gfx_line(im, X1, Y0, X1 + 2, Y0,
2143                          GRIDWIDTH, im->graph_col[GRC_GRID]);
2144                 gfx_dashed_line(im, X0 - 1, Y0,
2145                                 X1 + 1, Y0,
2146                                 GRIDWIDTH,
2147                                 im->
2148                                 graph_col[GRC_GRID],
2149                                 im->grid_dash_on, im->grid_dash_off);
2150             }
2151         }
2152     }
2153     return 1;
2154 }
2155
2156 /* this is frexp for base 10 */
2157 double    frexp10(
2158     double,
2159     double *);
2160 double frexp10(
2161     double x,
2162     double *e)
2163 {
2164     double    mnt;
2165     int       iexp;
2166
2167     iexp = floor(log((double)fabs(x)) / log((double)10));
2168     mnt = x / pow(10.0, iexp);
2169     if (mnt >= 10.0) {
2170         iexp++;
2171         mnt = x / pow(10.0, iexp);
2172     }
2173     *e = iexp;
2174     return mnt;
2175 }
2176
2177
2178 /* logaritmic horizontal grid */
2179 int horizontal_log_grid(
2180     image_desc_t
2181     *im)
2182 {
2183     double    yloglab[][10] = {
2184         {
2185          1.0, 10., 0.0, 0.0, 0.0, 0.0, 0.0,
2186          0.0, 0.0, 0.0}, {
2187                           1.0, 5.0, 10., 0.0, 0.0, 0.0, 0.0,
2188                           0.0, 0.0, 0.0}, {
2189                                            1.0, 2.0, 5.0, 7.0, 10., 0.0, 0.0,
2190                                            0.0, 0.0, 0.0}, {
2191                                                             1.0, 2.0, 4.0,
2192                                                             6.0, 8.0, 10.,
2193                                                             0.0,
2194                                                             0.0, 0.0, 0.0}, {
2195                                                                              1.0,
2196                                                                              2.0,
2197                                                                              3.0,
2198                                                                              4.0,
2199                                                                              5.0,
2200                                                                              6.0,
2201                                                                              7.0,
2202                                                                              8.0,
2203                                                                              9.0,
2204                                                                              10.},
2205         {
2206          0, 0, 0, 0, 0, 0, 0, 0, 0, 0}  /* last line */
2207     };
2208     int       i, j, val_exp, min_exp;
2209     double    nex;      /* number of decades in data */
2210     double    logscale; /* scale in logarithmic space */
2211     int       exfrac = 1;   /* decade spacing */
2212     int       mid = -1; /* row in yloglab for major grid */
2213     double    mspac;    /* smallest major grid spacing (pixels) */
2214     int       flab;     /* first value in yloglab to use */
2215     double    value, tmp, pre_value;
2216     double    X0, X1, Y0;
2217     char      graph_label[100];
2218
2219     nex = log10(im->maxval / im->minval);
2220     logscale = im->ysize / nex;
2221     /* major spacing for data with high dynamic range */
2222     while (logscale * exfrac < 3 * im->text_prop[TEXT_PROP_LEGEND].size) {
2223         if (exfrac == 1)
2224             exfrac = 3;
2225         else
2226             exfrac += 3;
2227     }
2228
2229     /* major spacing for less dynamic data */
2230     do {
2231         /* search best row in yloglab */
2232         mid++;
2233         for (i = 0; yloglab[mid][i + 1] < 10.0; i++);
2234         mspac = logscale * log10(10.0 / yloglab[mid][i]);
2235     }
2236     while (mspac >
2237            2 * im->text_prop[TEXT_PROP_LEGEND].size && yloglab[mid][0] > 0);
2238     if (mid)
2239         mid--;
2240     /* find first value in yloglab */
2241     for (flab = 0;
2242          yloglab[mid][flab] < 10
2243          && frexp10(im->minval, &tmp) > yloglab[mid][flab]; flab++);
2244     if (yloglab[mid][flab] == 10.0) {
2245         tmp += 1.0;
2246         flab = 0;
2247     }
2248     val_exp = tmp;
2249     if (val_exp % exfrac)
2250         val_exp += abs(-val_exp % exfrac);
2251     X0 = im->xorigin;
2252     X1 = im->xorigin + im->xsize;
2253     /* draw grid */
2254     pre_value = DNAN;
2255     while (1) {
2256
2257         value = yloglab[mid][flab] * pow(10.0, val_exp);
2258         if (AlmostEqual2sComplement(value, pre_value, 4))
2259             break;      /* it seems we are not converging */
2260         pre_value = value;
2261         Y0 = ytr(im, value);
2262         if (floor(Y0 + 0.5) <= im->yorigin - im->ysize)
2263             break;
2264         /* major grid line */
2265         gfx_line(im,
2266                  X0 - 2, Y0, X0, Y0, MGRIDWIDTH, im->graph_col[GRC_MGRID]);
2267         gfx_line(im, X1, Y0, X1 + 2, Y0,
2268                  MGRIDWIDTH, im->graph_col[GRC_MGRID]);
2269         gfx_dashed_line(im, X0 - 2, Y0,
2270                         X1 + 2, Y0,
2271                         MGRIDWIDTH,
2272                         im->
2273                         graph_col
2274                         [GRC_MGRID], im->grid_dash_on, im->grid_dash_off);
2275         /* label */
2276         if (im->extra_flags & FORCE_UNITS_SI) {
2277             int       scale;
2278             double    pvalue;
2279             char      symbol;
2280
2281             scale = floor(val_exp / 3.0);
2282             if (value >= 1.0)
2283                 pvalue = pow(10.0, val_exp % 3);
2284             else
2285                 pvalue = pow(10.0, ((val_exp + 1) % 3) + 2);
2286             pvalue *= yloglab[mid][flab];
2287             if (((scale + si_symbcenter) < (int) sizeof(si_symbol))
2288                 && ((scale + si_symbcenter) >= 0))
2289                 symbol = si_symbol[scale + si_symbcenter];
2290             else
2291                 symbol = '?';
2292             sprintf(graph_label, "%3.0f %c", pvalue, symbol);
2293         } else {
2294             sprintf(graph_label, "%3.0e", value);
2295         }
2296         if (im->second_axis_scale != 0){
2297                 char graph_label_right[100];
2298                 double sval = value*im->second_axis_scale+im->second_axis_shift;
2299                 if (im->second_axis_format[0] == '\0'){
2300                         if (im->extra_flags & FORCE_UNITS_SI) {
2301                                 double mfac = 1;
2302                                 char   *symb = "";
2303                                 auto_scale(im,&sval,&symb,&mfac);
2304                                 sprintf(graph_label_right,"%4.0f %s", sval,symb);
2305                         }
2306                         else {
2307                                 sprintf(graph_label_right,"%3.0e", sval);
2308                         }
2309                 }
2310                 else {
2311                       sprintf(graph_label_right,im->second_axis_format,sval,"");
2312                 }
2313
2314                 gfx_text ( im,
2315                                X1+7, Y0,
2316                                im->graph_col[GRC_FONT],
2317                                im->text_prop[TEXT_PROP_AXIS].font_desc,
2318                                im->tabwidth,0.0, GFX_H_LEFT, GFX_V_CENTER,
2319                                graph_label_right );
2320         }
2321
2322         gfx_text(im,
2323                  X0 -
2324                  im->
2325                  text_prop[TEXT_PROP_AXIS].
2326                  size, Y0,
2327                  im->graph_col[GRC_FONT],
2328                  im->
2329                  text_prop[TEXT_PROP_AXIS].
2330                  font_desc,
2331                  im->tabwidth, 0.0,
2332                  GFX_H_RIGHT, GFX_V_CENTER, graph_label);
2333         /* minor grid */
2334         if (mid < 4 && exfrac == 1) {
2335             /* find first and last minor line behind current major line
2336              * i is the first line and j tha last */
2337             if (flab == 0) {
2338                 min_exp = val_exp - 1;
2339                 for (i = 1; yloglab[mid][i] < 10.0; i++);
2340                 i = yloglab[mid][i - 1] + 1;
2341                 j = 10;
2342             } else {
2343                 min_exp = val_exp;
2344                 i = yloglab[mid][flab - 1] + 1;
2345                 j = yloglab[mid][flab];
2346             }
2347
2348             /* draw minor lines below current major line */
2349             for (; i < j; i++) {
2350
2351                 value = i * pow(10.0, min_exp);
2352                 if (value < im->minval)
2353                     continue;
2354                 Y0 = ytr(im, value);
2355                 if (floor(Y0 + 0.5) <= im->yorigin - im->ysize)
2356                     break;
2357                 /* draw lines */
2358                 gfx_line(im,
2359                          X0 - 2, Y0,
2360                          X0, Y0, GRIDWIDTH, im->graph_col[GRC_GRID]);
2361                 gfx_line(im, X1, Y0, X1 + 2, Y0,
2362                          GRIDWIDTH, im->graph_col[GRC_GRID]);
2363                 gfx_dashed_line(im, X0 - 1, Y0,
2364                                 X1 + 1, Y0,
2365                                 GRIDWIDTH,
2366                                 im->
2367                                 graph_col[GRC_GRID],
2368                                 im->grid_dash_on, im->grid_dash_off);
2369             }
2370         } else if (exfrac > 1) {
2371             for (i = val_exp - exfrac / 3 * 2; i < val_exp; i += exfrac / 3) {
2372                 value = pow(10.0, i);
2373                 if (value < im->minval)
2374                     continue;
2375                 Y0 = ytr(im, value);
2376                 if (floor(Y0 + 0.5) <= im->yorigin - im->ysize)
2377                     break;
2378                 /* draw lines */
2379                 gfx_line(im,
2380                          X0 - 2, Y0,
2381                          X0, Y0, GRIDWIDTH, im->graph_col[GRC_GRID]);
2382                 gfx_line(im, X1, Y0, X1 + 2, Y0,
2383                          GRIDWIDTH, im->graph_col[GRC_GRID]);
2384                 gfx_dashed_line(im, X0 - 1, Y0,
2385                                 X1 + 1, Y0,
2386                                 GRIDWIDTH,
2387                                 im->
2388                                 graph_col[GRC_GRID],
2389                                 im->grid_dash_on, im->grid_dash_off);
2390             }
2391         }
2392
2393         /* next decade */
2394         if (yloglab[mid][++flab] == 10.0) {
2395             flab = 0;
2396             val_exp += exfrac;
2397         }
2398     }
2399
2400     /* draw minor lines after highest major line */
2401     if (mid < 4 && exfrac == 1) {
2402         /* find first and last minor line below current major line
2403          * i is the first line and j tha last */
2404         if (flab == 0) {
2405             min_exp = val_exp - 1;
2406             for (i = 1; yloglab[mid][i] < 10.0; i++);
2407             i = yloglab[mid][i - 1] + 1;
2408             j = 10;
2409         } else {
2410             min_exp = val_exp;
2411             i = yloglab[mid][flab - 1] + 1;
2412             j = yloglab[mid][flab];
2413         }
2414
2415         /* draw minor lines below current major line */
2416         for (; i < j; i++) {
2417
2418             value = i * pow(10.0, min_exp);
2419             if (value < im->minval)
2420                 continue;
2421             Y0 = ytr(im, value);
2422             if (floor(Y0 + 0.5) <= im->yorigin - im->ysize)
2423                 break;
2424             /* draw lines */
2425             gfx_line(im,
2426                      X0 - 2, Y0, X0, Y0, GRIDWIDTH, im->graph_col[GRC_GRID]);
2427             gfx_line(im, X1, Y0, X1 + 2, Y0,
2428                      GRIDWIDTH, im->graph_col[GRC_GRID]);
2429             gfx_dashed_line(im, X0 - 1, Y0,
2430                             X1 + 1, Y0,
2431                             GRIDWIDTH,
2432                             im->
2433                             graph_col[GRC_GRID],
2434                             im->grid_dash_on, im->grid_dash_off);
2435         }
2436     }
2437     /* fancy minor gridlines */
2438     else if (exfrac > 1) {
2439         for (i = val_exp - exfrac / 3 * 2; i < val_exp; i += exfrac / 3) {
2440             value = pow(10.0, i);
2441             if (value < im->minval)
2442                 continue;
2443             Y0 = ytr(im, value);
2444             if (floor(Y0 + 0.5) <= im->yorigin - im->ysize)
2445                 break;
2446             /* draw lines */
2447             gfx_line(im,
2448                      X0 - 2, Y0, X0, Y0, GRIDWIDTH, im->graph_col[GRC_GRID]);
2449             gfx_line(im, X1, Y0, X1 + 2, Y0,
2450                      GRIDWIDTH, im->graph_col[GRC_GRID]);
2451             gfx_dashed_line(im, X0 - 1, Y0,
2452                             X1 + 1, Y0,
2453                             GRIDWIDTH,
2454                             im->
2455                             graph_col[GRC_GRID],
2456                             im->grid_dash_on, im->grid_dash_off);
2457         }
2458     }
2459
2460     return 1;
2461 }
2462
2463
2464 void vertical_grid(
2465     image_desc_t *im)
2466 {
2467     int       xlab_sel; /* which sort of label and grid ? */
2468     time_t    ti, tilab, timajor;
2469     long      factor;
2470     char      graph_label[100];
2471     double    X0, Y0, Y1;   /* points for filled graph and more */
2472     struct tm tm;
2473
2474     /* the type of time grid is determined by finding
2475        the number of seconds per pixel in the graph */
2476     if (im->xlab_user.minsec == -1) {
2477         factor = (im->end - im->start) / im->xsize;
2478         xlab_sel = 0;
2479         while (xlab[xlab_sel + 1].minsec !=
2480                -1 && xlab[xlab_sel + 1].minsec <= factor) {
2481             xlab_sel++;
2482         }               /* pick the last one */
2483         while (xlab[xlab_sel - 1].minsec ==
2484                xlab[xlab_sel].minsec
2485                && xlab[xlab_sel].length > (im->end - im->start)) {
2486             xlab_sel--;
2487         }               /* go back to the smallest size */
2488         im->xlab_user.gridtm = xlab[xlab_sel].gridtm;
2489         im->xlab_user.gridst = xlab[xlab_sel].gridst;
2490         im->xlab_user.mgridtm = xlab[xlab_sel].mgridtm;
2491         im->xlab_user.mgridst = xlab[xlab_sel].mgridst;
2492         im->xlab_user.labtm = xlab[xlab_sel].labtm;
2493         im->xlab_user.labst = xlab[xlab_sel].labst;
2494         im->xlab_user.precis = xlab[xlab_sel].precis;
2495         im->xlab_user.stst = xlab[xlab_sel].stst;
2496     }
2497
2498     /* y coords are the same for every line ... */
2499     Y0 = im->yorigin;
2500     Y1 = im->yorigin - im->ysize;
2501     /* paint the minor grid */
2502     if (!(im->extra_flags & NOMINOR)) {
2503         for (ti = find_first_time(im->start,
2504                                   im->
2505                                   xlab_user.
2506                                   gridtm,
2507                                   im->
2508                                   xlab_user.
2509                                   gridst),
2510              timajor =
2511              find_first_time(im->start,
2512                              im->xlab_user.
2513                              mgridtm,
2514                              im->xlab_user.
2515                              mgridst);
2516              ti < im->end && ti != -1;
2517              ti =
2518              find_next_time(ti, im->xlab_user.gridtm, im->xlab_user.gridst)
2519             ) {
2520             /* are we inside the graph ? */
2521             if (ti < im->start || ti > im->end)
2522                 continue;
2523             while (timajor < ti && timajor != -1) {
2524                 timajor = find_next_time(timajor,
2525                                          im->
2526                                          xlab_user.
2527                                          mgridtm, im->xlab_user.mgridst);
2528             }
2529             if (timajor == -1) break; /* fail in case of problems with time increments */
2530             if (ti == timajor)
2531                 continue;   /* skip as falls on major grid line */
2532             X0 = xtr(im, ti);
2533             gfx_line(im, X0, Y1 - 2, X0, Y1,
2534                      GRIDWIDTH, im->graph_col[GRC_GRID]);
2535             gfx_line(im, X0, Y0, X0, Y0 + 2,
2536                      GRIDWIDTH, im->graph_col[GRC_GRID]);
2537             gfx_dashed_line(im, X0, Y0 + 1, X0,
2538                             Y1 - 1, GRIDWIDTH,
2539                             im->
2540                             graph_col[GRC_GRID],
2541                             im->grid_dash_on, im->grid_dash_off);
2542         }
2543     }
2544
2545     /* paint the major grid */
2546     for (ti = find_first_time(im->start,
2547                               im->
2548                               xlab_user.
2549                               mgridtm,
2550                               im->
2551                               xlab_user.
2552                               mgridst);
2553          ti < im->end && ti != -1;
2554          ti = find_next_time(ti, im->xlab_user.mgridtm, im->xlab_user.mgridst)
2555         ) {
2556         /* are we inside the graph ? */
2557         if (ti < im->start || ti > im->end)
2558             continue;
2559         X0 = xtr(im, ti);
2560         gfx_line(im, X0, Y1 - 2, X0, Y1,
2561                  MGRIDWIDTH, im->graph_col[GRC_MGRID]);
2562         gfx_line(im, X0, Y0, X0, Y0 + 3,
2563                  MGRIDWIDTH, im->graph_col[GRC_MGRID]);
2564         gfx_dashed_line(im, X0, Y0 + 3, X0,
2565                         Y1 - 2, MGRIDWIDTH,
2566                         im->
2567                         graph_col
2568                         [GRC_MGRID], im->grid_dash_on, im->grid_dash_off);
2569     }
2570     /* paint the labels below the graph */
2571     for (ti =
2572          find_first_time(im->start -
2573                          im->xlab_user.
2574                          precis / 2,
2575                          im->xlab_user.
2576                          labtm,
2577                          im->xlab_user.
2578                          labst);
2579          (ti <=
2580          im->end -
2581          im->xlab_user.precis / 2) && ti != -1;
2582          ti = find_next_time(ti, im->xlab_user.labtm, im->xlab_user.labst)
2583         ) {
2584         tilab = ti + im->xlab_user.precis / 2;  /* correct time for the label */
2585         /* are we inside the graph ? */
2586         if (tilab < im->start || tilab > im->end)
2587             continue;
2588 #if HAVE_STRFTIME
2589         localtime_r(&tilab, &tm);
2590         strftime(graph_label, 99, im->xlab_user.stst, &tm);
2591 #else
2592 # error "your libc has no strftime I guess we'll abort the exercise here."
2593 #endif
2594         gfx_text(im,
2595                  xtr(im, tilab),
2596                  Y0 + 3,
2597                  im->graph_col[GRC_FONT],
2598                  im->
2599                  text_prop[TEXT_PROP_AXIS].
2600                  font_desc,
2601                  im->tabwidth, 0.0,
2602                  GFX_H_CENTER, GFX_V_TOP, graph_label);
2603     }
2604
2605 }
2606
2607
2608 void axis_paint(
2609     image_desc_t *im)
2610 {
2611     /* draw x and y axis */
2612     /* gfx_line ( im->canvas, im->xorigin+im->xsize,im->yorigin,
2613        im->xorigin+im->xsize,im->yorigin-im->ysize,
2614        GRIDWIDTH, im->graph_col[GRC_AXIS]);
2615
2616        gfx_line ( im->canvas, im->xorigin,im->yorigin-im->ysize,
2617        im->xorigin+im->xsize,im->yorigin-im->ysize,
2618        GRIDWIDTH, im->graph_col[GRC_AXIS]); */
2619
2620     gfx_line(im, im->xorigin - 4,
2621              im->yorigin,
2622              im->xorigin + im->xsize +
2623              4, im->yorigin, MGRIDWIDTH, im->graph_col[GRC_AXIS]);
2624     gfx_line(im, im->xorigin,
2625              im->yorigin + 4,
2626              im->xorigin,
2627              im->yorigin - im->ysize -
2628              4, MGRIDWIDTH, im->graph_col[GRC_AXIS]);
2629     /* arrow for X and Y axis direction */
2630     gfx_new_area(im, im->xorigin + im->xsize + 2, im->yorigin - 3, im->xorigin + im->xsize + 2, im->yorigin + 3, im->xorigin + im->xsize + 7, im->yorigin,  /* horyzontal */
2631                  im->graph_col[GRC_ARROW]);
2632     gfx_close_path(im);
2633     gfx_new_area(im, im->xorigin - 3, im->yorigin - im->ysize - 2, im->xorigin + 3, im->yorigin - im->ysize - 2, im->xorigin, im->yorigin - im->ysize - 7,  /* vertical */
2634                  im->graph_col[GRC_ARROW]);
2635     gfx_close_path(im);
2636     if (im->second_axis_scale != 0){
2637        gfx_line ( im, im->xorigin+im->xsize,im->yorigin+4,
2638                          im->xorigin+im->xsize,im->yorigin-im->ysize-4,
2639                          MGRIDWIDTH, im->graph_col[GRC_AXIS]);
2640        gfx_new_area ( im,
2641                    im->xorigin+im->xsize-2,  im->yorigin-im->ysize-2,
2642                    im->xorigin+im->xsize+3,  im->yorigin-im->ysize-2,
2643                    im->xorigin+im->xsize,    im->yorigin-im->ysize-7, /* LINEOFFSET */
2644                    im->graph_col[GRC_ARROW]);
2645        gfx_close_path(im);
2646     }
2647
2648 }
2649
2650 void grid_paint(
2651     image_desc_t *im)
2652 {
2653     long      i;
2654     int       res = 0;
2655     double    X0, Y0;   /* points for filled graph and more */
2656     struct gfx_color_t water_color;
2657
2658     if (im->draw_3d_border > 0) {
2659             /* draw 3d border */
2660             i = im->draw_3d_border;
2661             gfx_new_area(im, 0, im->yimg,
2662                          i, im->yimg - i, i, i, im->graph_col[GRC_SHADEA]);
2663             gfx_add_point(im, im->ximg - i, i);
2664             gfx_add_point(im, im->ximg, 0);
2665             gfx_add_point(im, 0, 0);
2666             gfx_close_path(im);
2667             gfx_new_area(im, i, im->yimg - i,
2668                          im->ximg - i,
2669                          im->yimg - i, im->ximg - i, i, im->graph_col[GRC_SHADEB]);
2670             gfx_add_point(im, im->ximg, 0);
2671             gfx_add_point(im, im->ximg, im->yimg);
2672             gfx_add_point(im, 0, im->yimg);
2673             gfx_close_path(im);
2674     }
2675     if (im->draw_x_grid == 1)
2676         vertical_grid(im);
2677     if (im->draw_y_grid == 1) {
2678         if (im->logarithmic) {
2679             res = horizontal_log_grid(im);
2680         } else {
2681             res = draw_horizontal_grid(im);
2682         }
2683
2684         /* dont draw horizontal grid if there is no min and max val */
2685         if (!res) {
2686             char     *nodata = "No Data found";
2687
2688             gfx_text(im, im->ximg / 2,
2689                      (2 * im->yorigin -
2690                       im->ysize) / 2,
2691                      im->graph_col[GRC_FONT],
2692                      im->
2693                      text_prop[TEXT_PROP_AXIS].
2694                      font_desc,
2695                      im->tabwidth, 0.0,
2696                      GFX_H_CENTER, GFX_V_CENTER, nodata);
2697         }
2698     }
2699
2700     /* yaxis unit description */
2701     if (im->ylegend[0] != '\0'){
2702         gfx_text(im,
2703                  im->xOriginLegendY+10,
2704                  im->yOriginLegendY,
2705                  im->graph_col[GRC_FONT],
2706                  im->
2707                  text_prop[TEXT_PROP_UNIT].
2708                  font_desc,
2709                  im->tabwidth,
2710                  RRDGRAPH_YLEGEND_ANGLE, GFX_H_CENTER, GFX_V_CENTER, im->ylegend);
2711
2712     }
2713     if (im->second_axis_legend[0] != '\0'){
2714             gfx_text( im,
2715                   im->xOriginLegendY2+10,
2716                   im->yOriginLegendY2,
2717                   im->graph_col[GRC_FONT],
2718                   im->text_prop[TEXT_PROP_UNIT].font_desc,
2719                   im->tabwidth,
2720                   RRDGRAPH_YLEGEND_ANGLE,
2721                   GFX_H_CENTER, GFX_V_CENTER,
2722                   im->second_axis_legend);
2723     }
2724
2725     /* graph title */
2726     gfx_text(im,
2727              im->xOriginTitle, im->yOriginTitle+6,
2728              im->graph_col[GRC_FONT],
2729              im->
2730              text_prop[TEXT_PROP_TITLE].
2731              font_desc,
2732              im->tabwidth, 0.0, GFX_H_CENTER, GFX_V_TOP, im->title);
2733     /* rrdtool 'logo' */
2734     if (!(im->extra_flags & NO_RRDTOOL_TAG)){
2735         water_color = im->graph_col[GRC_FONT];
2736         water_color.alpha = 0.3;
2737         double xpos = im->legendposition == EAST ? im->xOriginLegendY : im->ximg - 4;
2738         gfx_text(im, xpos, 5,
2739                  water_color,
2740                  im->
2741                  text_prop[TEXT_PROP_WATERMARK].
2742                  font_desc, im->tabwidth,
2743                  -90, GFX_H_LEFT, GFX_V_TOP, "RRDTOOL / TOBI OETIKER");
2744     }
2745     /* graph watermark */
2746     if (im->watermark[0] != '\0') {
2747         water_color = im->graph_col[GRC_FONT];
2748         water_color.alpha = 0.3;
2749         gfx_text(im,
2750                  im->ximg / 2, im->yimg - 6,
2751                  water_color,
2752                  im->
2753                  text_prop[TEXT_PROP_WATERMARK].
2754                  font_desc, im->tabwidth, 0,
2755                  GFX_H_CENTER, GFX_V_BOTTOM, im->watermark);
2756     }
2757
2758     /* graph labels */
2759     if (!(im->extra_flags & NOLEGEND) && !(im->extra_flags & ONLY_GRAPH)) {
2760         for (i = 0; i < im->gdes_c; i++) {
2761             if (im->gdes[i].legend[0] == '\0')
2762                 continue;
2763             /* im->gdes[i].leg_y is the bottom of the legend */
2764             X0 = im->xOriginLegend + im->gdes[i].leg_x;
2765             Y0 = im->legenddirection == TOP_DOWN ? im->yOriginLegend + im->gdes[i].leg_y : im->yOriginLegend + im->legendheight - im->gdes[i].leg_y;
2766             gfx_text(im, X0, Y0,
2767                      im->graph_col[GRC_FONT],
2768                      im->
2769                      text_prop
2770                      [TEXT_PROP_LEGEND].font_desc,
2771                      im->tabwidth, 0.0,
2772                      GFX_H_LEFT, GFX_V_BOTTOM, im->gdes[i].legend);
2773             /* The legend for GRAPH items starts with "M " to have
2774                enough space for the box */
2775             if (im->gdes[i].gf != GF_PRINT &&
2776                 im->gdes[i].gf != GF_GPRINT && im->gdes[i].gf != GF_COMMENT) {
2777                 double    boxH, boxV;
2778                 double    X1, Y1;
2779
2780                 boxH = gfx_get_text_width(im, 0,
2781                                           im->
2782                                           text_prop
2783                                           [TEXT_PROP_LEGEND].
2784                                           font_desc,
2785                                           im->tabwidth, "o") * 1.2;
2786                 boxV = boxH;
2787                 /* shift the box up a bit */
2788                 Y0 -= boxV * 0.4;
2789
2790         if (im->dynamic_labels && im->gdes[i].gf == GF_HRULE) { /* [-] */ 
2791                         cairo_save(im->cr);
2792                         cairo_new_path(im->cr);
2793                         cairo_set_line_width(im->cr, 1.0);
2794                         gfx_line(im,
2795                                 X0, Y0 - boxV / 2,
2796                                 X0 + boxH, Y0 - boxV / 2,
2797                                 1.0, im->gdes[i].col);
2798                         gfx_close_path(im);
2799                 } else if (im->dynamic_labels && im->gdes[i].gf == GF_VRULE) { /* [|] */
2800                         cairo_save(im->cr);
2801                         cairo_new_path(im->cr);
2802                         cairo_set_line_width(im->cr, 1.0);
2803                         gfx_line(im,
2804                                 X0 + boxH / 2, Y0,
2805                                 X0 + boxH / 2, Y0 - boxV,
2806                                 1.0, im->gdes[i].col);
2807                         gfx_close_path(im);
2808                 } else if (im->dynamic_labels && im->gdes[i].gf == GF_LINE) { /* [/] */
2809                         cairo_save(im->cr);
2810                         cairo_new_path(im->cr);
2811                         cairo_set_line_width(im->cr, im->gdes[i].linewidth);
2812                         gfx_line(im,
2813                                 X0, Y0,
2814                                 X0 + boxH, Y0 - boxV,
2815                                 im->gdes[i].linewidth, im->gdes[i].col);
2816                         gfx_close_path(im);
2817                 } else {
2818                 /* make sure transparent colors show up the same way as in the graph */
2819                         gfx_new_area(im,
2820                                      X0, Y0 - boxV,
2821                                      X0, Y0, X0 + boxH, Y0, im->graph_col[GRC_BACK]);
2822                         gfx_add_point(im, X0 + boxH, Y0 - boxV);
2823                         gfx_close_path(im);
2824                         gfx_new_area(im, X0, Y0 - boxV, X0,
2825                                      Y0, X0 + boxH, Y0, im->gdes[i].col);
2826                         gfx_add_point(im, X0 + boxH, Y0 - boxV);
2827                         gfx_close_path(im);
2828                         cairo_save(im->cr);
2829                         cairo_new_path(im->cr);
2830                         cairo_set_line_width(im->cr, 1.0);
2831                         X1 = X0 + boxH;
2832                         Y1 = Y0 - boxV;
2833                         gfx_line_fit(im, &X0, &Y0);
2834                         gfx_line_fit(im, &X1, &Y1);
2835                         cairo_move_to(im->cr, X0, Y0);
2836                         cairo_line_to(im->cr, X1, Y0);
2837                         cairo_line_to(im->cr, X1, Y1);
2838                         cairo_line_to(im->cr, X0, Y1);
2839                         cairo_close_path(im->cr);
2840                         cairo_set_source_rgba(im->cr,
2841                                               im->graph_col[GRC_FRAME].red,
2842                                               im->graph_col[GRC_FRAME].green,
2843                                               im->graph_col[GRC_FRAME].blue,
2844                                               im->graph_col[GRC_FRAME].alpha);
2845                 }
2846                 if (im->gdes[i].dash) {
2847                     /* make box borders in legend dashed if the graph is dashed */
2848                     double    dashes[] = {
2849                         3.0
2850                     };
2851                     cairo_set_dash(im->cr, dashes, 1, 0.0);
2852                 }
2853                 cairo_stroke(im->cr);
2854                 cairo_restore(im->cr);
2855             }
2856         }
2857     }
2858 }
2859
2860
2861 /*****************************************************
2862  * lazy check make sure we rely need to create this graph
2863  *****************************************************/
2864
2865 int lazy_check(
2866     image_desc_t *im)
2867 {
2868     FILE     *fd = NULL;
2869     int       size = 1;
2870     struct stat imgstat;
2871
2872     if (im->lazy == 0)
2873         return 0;       /* no lazy option */
2874     if (strlen(im->graphfile) == 0)
2875         return 0;       /* inmemory option */
2876     if (stat(im->graphfile, &imgstat) != 0)
2877         return 0;       /* can't stat */
2878     /* one pixel in the existing graph is more then what we would
2879        change here ... */
2880     if (time(NULL) - imgstat.st_mtime > (im->end - im->start) / im->xsize)
2881         return 0;
2882     if ((fd = fopen(im->graphfile, "rb")) == NULL)
2883         return 0;       /* the file does not exist */
2884     switch (im->imgformat) {
2885     case IF_PNG:
2886         size = PngSize(fd, &(im->ximg), &(im->yimg));
2887         break;
2888     default:
2889         size = 1;
2890     }
2891     fclose(fd);
2892     return size;
2893 }
2894
2895
2896 int graph_size_location(
2897     image_desc_t
2898     *im,
2899     int elements)
2900 {
2901     /* The actual size of the image to draw is determined from
2902      ** several sources.  The size given on the command line is
2903      ** the graph area but we need more as we have to draw labels
2904      ** and other things outside the graph area. If the option
2905      ** --full-size-mode is selected the size defines the total
2906      ** image size and the size available for the graph is
2907      ** calculated.
2908      */
2909
2910     /** +---+-----------------------------------+
2911      ** | y |...............graph title.........|
2912      ** |   +---+-------------------------------+
2913      ** | a | y |                               |
2914      ** | x |   |                               |
2915      ** | i | a |                               |
2916      ** | s | x |       main graph area         |
2917      ** |   | i |                               |
2918      ** | t | s |                               |
2919      ** | i |   |                               |
2920      ** | t | l |                               |
2921      ** | l | b +-------------------------------+
2922      ** | e | l |       x axis labels           |
2923      ** +---+---+-------------------------------+
2924      ** |....................legends............|
2925      ** +---------------------------------------+
2926      ** |                   watermark           |
2927      ** +---------------------------------------+
2928      */
2929
2930     int       Xvertical = 0, Xvertical2 = 0, Ytitle =
2931         0, Xylabel = 0, Xmain = 0, Ymain =
2932         0, Yxlabel = 0, Xspacing = 15, Yspacing = 15, Ywatermark = 4;
2933
2934     // no legends and no the shall be plotted it's easy
2935     if (im->extra_flags & ONLY_GRAPH) {
2936         im->xorigin = 0;
2937         im->ximg = im->xsize;
2938         im->yimg = im->ysize;
2939         im->yorigin = im->ysize;
2940         ytr(im, DNAN);
2941         return 0;
2942     }
2943
2944     if(im->watermark[0] != '\0') {
2945         Ywatermark = im->text_prop[TEXT_PROP_WATERMARK].size * 2;
2946     }
2947
2948     // calculate the width of the left vertical legend
2949     if (im->ylegend[0] != '\0') {
2950         Xvertical = im->text_prop[TEXT_PROP_UNIT].size * 2;
2951     }
2952
2953     // calculate the width of the right vertical legend
2954     if (im->second_axis_legend[0] != '\0') {
2955         Xvertical2 = im->text_prop[TEXT_PROP_UNIT].size * 2;
2956     }
2957     else{
2958         Xvertical2 = Xspacing;
2959     }
2960
2961     if (im->title[0] != '\0') {
2962         /* The title is placed "inbetween" two text lines so it
2963          ** automatically has some vertical spacing.  The horizontal
2964          ** spacing is added here, on each side.
2965          */
2966         /* if necessary, reduce the font size of the title until it fits the image width */
2967         Ytitle = im->text_prop[TEXT_PROP_TITLE].size * 2.6 + 10;
2968     }
2969     else{
2970         // we have no title; get a little clearing from the top
2971         Ytitle = Yspacing;
2972     }
2973
2974     if (elements) {
2975         if (im->draw_x_grid) {
2976             // calculate the height of the horizontal labelling
2977             Yxlabel = im->text_prop[TEXT_PROP_AXIS].size * 2.5;
2978         }
2979         if (im->draw_y_grid || im->forceleftspace) {
2980             // calculate the width of the vertical labelling
2981             Xylabel =
2982                 gfx_get_text_width(im, 0,
2983                                    im->text_prop[TEXT_PROP_AXIS].font_desc,
2984                                    im->tabwidth, "0") * im->unitslength;
2985         }
2986     }
2987
2988     // add some space to the labelling
2989     Xylabel += Xspacing;
2990
2991     /* If the legend is printed besides the graph the width has to be
2992      ** calculated first. Placing the legend north or south of the
2993      ** graph requires the width calculation first, so the legend is
2994      ** skipped for the moment.
2995      */
2996     im->legendheight = 0;
2997     im->legendwidth = 0;
2998     if (!(im->extra_flags & NOLEGEND)) {
2999         if(im->legendposition == WEST || im->legendposition == EAST){
3000             if (leg_place(im, 1) == -1){
3001                 return -1;
3002             }
3003         }
3004     }
3005
3006     if (im->extra_flags & FULL_SIZE_MODE) {
3007
3008         /* The actual size of the image to draw has been determined by the user.
3009          ** The graph area is the space remaining after accounting for the legend,
3010          ** the watermark, the axis labels, and the title.
3011          */
3012         im->ximg = im->xsize;
3013         im->yimg = im->ysize;
3014         Xmain = im->ximg;
3015         Ymain = im->yimg;
3016
3017         /* Now calculate the total size.  Insert some spacing where
3018            desired.  im->xorigin and im->yorigin need to correspond
3019            with the lower left corner of the main graph area or, if
3020            this one is not set, the imaginary box surrounding the
3021            pie chart area. */
3022         /* Initial size calculation for the main graph area */
3023
3024         Xmain -= Xylabel;// + Xspacing;
3025         if((im->legendposition == WEST || im->legendposition == EAST) && !(im->extra_flags & NOLEGEND) ){
3026             Xmain -= im->legendwidth;// + Xspacing;
3027         }
3028         if (im->second_axis_scale != 0){
3029             Xmain -= Xylabel;
3030         }
3031         if (!(im->extra_flags & NO_RRDTOOL_TAG)){
3032             Xmain -= Xspacing;
3033         }
3034
3035         Xmain -= Xvertical + Xvertical2;
3036
3037         /* limit the remaining space to 0 */
3038         if(Xmain < 1){
3039             Xmain = 1;
3040         }
3041         im->xsize = Xmain;
3042
3043         /* Putting the legend north or south, the height can now be calculated */
3044         if (!(im->extra_flags & NOLEGEND)) {
3045             if(im->legendposition == NORTH || im->legendposition == SOUTH){
3046                 im->legendwidth = im->ximg;
3047                 if (leg_place(im, 0) == -1){
3048                     return -1;
3049                 }
3050             }
3051         }
3052
3053         if( (im->legendposition == NORTH || im->legendposition == SOUTH)  && !(im->extra_flags & NOLEGEND) ){
3054             Ymain -=  Yxlabel + im->legendheight;
3055         }
3056         else{
3057             Ymain -= Yxlabel;
3058         }
3059
3060         /* reserve space for the title *or* some padding above the graph */
3061         Ymain -= Ytitle;
3062
3063             /* reserve space for padding below the graph */
3064         if (im->extra_flags & NOLEGEND) {
3065             Ymain -= 0.5*Yspacing;
3066         }
3067
3068         if (im->watermark[0] != '\0') {
3069             Ymain -= Ywatermark;
3070         }
3071         /* limit the remaining height to 0 */
3072         if(Ymain < 1){
3073             Ymain = 1;
3074         }
3075         im->ysize = Ymain;
3076     } else {            /* dimension options -width and -height refer to the dimensions of the main graph area */
3077
3078         /* The actual size of the image to draw is determined from
3079          ** several sources.  The size given on the command line is
3080          ** the graph area but we need more as we have to draw labels
3081          ** and other things outside the graph area.
3082          */
3083
3084         if (elements) {
3085             Xmain = im->xsize; // + Xspacing;
3086             Ymain = im->ysize;
3087         }
3088
3089         im->ximg = Xmain + Xylabel;
3090         if (!(im->extra_flags & NO_RRDTOOL_TAG)){
3091             im->ximg += Xspacing;
3092         }
3093
3094         if( (im->legendposition == WEST || im->legendposition == EAST) && !(im->extra_flags & NOLEGEND) ){
3095             im->ximg += im->legendwidth;// + Xspacing;
3096         }
3097         if (im->second_axis_scale != 0){
3098             im->ximg += Xylabel;
3099         }
3100
3101         im->ximg += Xvertical + Xvertical2;
3102
3103         if (!(im->extra_flags & NOLEGEND)) {
3104             if(im->legendposition == NORTH || im->legendposition == SOUTH){
3105                 im->legendwidth = im->ximg;
3106                 if (leg_place(im, 0) == -1){
3107                     return -1;
3108                 }
3109             }
3110         }
3111
3112         im->yimg = Ymain + Yxlabel;
3113         if( (im->legendposition == NORTH || im->legendposition == SOUTH)  && !(im->extra_flags & NOLEGEND) ){
3114              im->yimg += im->legendheight;
3115         }
3116
3117         /* reserve space for the title *or* some padding above the graph */
3118         if (Ytitle) {
3119             im->yimg += Ytitle;
3120         } else {
3121             im->yimg += 1.5 * Yspacing;
3122         }
3123         /* reserve space for padding below the graph */
3124         if (im->extra_flags & NOLEGEND) {
3125             im->yimg += 0.5*Yspacing;
3126         }
3127
3128         if (im->watermark[0] != '\0') {
3129             im->yimg += Ywatermark;
3130         }
3131     }
3132
3133
3134     /* In case of putting the legend in west or east position the first
3135      ** legend calculation might lead to wrong positions if some items
3136      ** are not aligned on the left hand side (e.g. centered) as the
3137      ** legendwidth wight have been increased after the item was placed.
3138      ** In this case the positions have to be recalculated.
3139      */
3140     if (!(im->extra_flags & NOLEGEND)) {
3141         if(im->legendposition == WEST || im->legendposition == EAST){
3142             if (leg_place(im, 0) == -1){
3143                 return -1;
3144             }
3145         }
3146     }
3147
3148     /* After calculating all dimensions
3149      ** it is now possible to calculate
3150      ** all offsets.
3151      */
3152     switch(im->legendposition){
3153         case NORTH:
3154             im->xOriginTitle   = (im->ximg / 2);
3155             im->yOriginTitle   = 0;
3156
3157             im->xOriginLegend  = 0;
3158             im->yOriginLegend  = Ytitle;
3159
3160             im->xOriginLegendY = 0;
3161             im->yOriginLegendY = Ytitle + im->legendheight + (Ymain / 2) + Yxlabel;
3162
3163             im->xorigin        = Xvertical + Xylabel;
3164             im->yorigin        = Ytitle + im->legendheight + Ymain;
3165
3166             im->xOriginLegendY2 = Xvertical + Xylabel + Xmain;
3167             if (im->second_axis_scale != 0){
3168                 im->xOriginLegendY2 += Xylabel;
3169             }
3170             im->yOriginLegendY2 = Ytitle + im->legendheight + (Ymain / 2) + Yxlabel;
3171
3172             break;
3173
3174         case WEST:
3175             im->xOriginTitle   = im->legendwidth + im->xsize / 2;
3176             im->yOriginTitle   = 0;
3177
3178             im->xOriginLegend  = 0;
3179             im->yOriginLegend  = Ytitle;
3180
3181             im->xOriginLegendY = im->legendwidth;
3182             im->yOriginLegendY = Ytitle + (Ymain / 2);
3183
3184             im->xorigin        = im->legendwidth + Xvertical + Xylabel;
3185             im->yorigin        = Ytitle + Ymain;
3186
3187             im->xOriginLegendY2 = im->legendwidth + Xvertical + Xylabel + Xmain;
3188             if (im->second_axis_scale != 0){
3189                 im->xOriginLegendY2 += Xylabel;
3190             }
3191             im->yOriginLegendY2 = Ytitle + (Ymain / 2);
3192
3193             break;
3194
3195         case SOUTH:
3196             im->xOriginTitle   = im->ximg / 2;
3197             im->yOriginTitle   = 0;
3198
3199             im->xOriginLegend  = 0;
3200             im->yOriginLegend  = Ytitle + Ymain + Yxlabel;
3201
3202             im->xOriginLegendY = 0;
3203             im->yOriginLegendY = Ytitle + (Ymain / 2);
3204
3205             im->xorigin        = Xvertical + Xylabel;
3206             im->yorigin        = Ytitle + Ymain;
3207
3208             im->xOriginLegendY2 = Xvertical + Xylabel + Xmain;
3209             if (im->second_axis_scale != 0){
3210                 im->xOriginLegendY2 += Xylabel;
3211             }
3212             im->yOriginLegendY2 = Ytitle + (Ymain / 2);
3213
3214             break;
3215
3216         case EAST:
3217             im->xOriginTitle   = im->xsize / 2;
3218             im->yOriginTitle   = 0;
3219
3220             im->xOriginLegend  = Xvertical + Xylabel + Xmain + Xvertical2;
3221             if (im->second_axis_scale != 0){
3222                 im->xOriginLegend += Xylabel;
3223             }
3224             im->yOriginLegend  = Ytitle;
3225
3226             im->xOriginLegendY = 0;
3227             im->yOriginLegendY = Ytitle + (Ymain / 2);
3228
3229             im->xorigin        = Xvertical + Xylabel;
3230             im->yorigin        = Ytitle + Ymain;
3231
3232             im->xOriginLegendY2 = Xvertical + Xylabel + Xmain;
3233             if (im->second_axis_scale != 0){
3234                 im->xOriginLegendY2 += Xylabel;
3235             }
3236             im->yOriginLegendY2 = Ytitle + (Ymain / 2);
3237
3238             if (!(im->extra_flags & NO_RRDTOOL_TAG)){
3239                 im->xOriginTitle    += Xspacing;
3240                 im->xOriginLegend   += Xspacing;
3241                 im->xOriginLegendY  += Xspacing;
3242                 im->xorigin         += Xspacing;
3243                 im->xOriginLegendY2 += Xspacing;
3244             }
3245             break;
3246     }
3247
3248     xtr(im, 0);
3249     ytr(im, DNAN);
3250     return 0;
3251 }
3252
3253 static cairo_status_t cairo_output(
3254     void *closure,
3255     const unsigned char
3256     *data,
3257     unsigned int length)
3258 {
3259     image_desc_t *im = (image_desc_t*)closure;
3260
3261     im->rendered_image =
3262         (unsigned char*)realloc(im->rendered_image, im->rendered_image_size + length);
3263     if (im->rendered_image == NULL)
3264         return CAIRO_STATUS_WRITE_ERROR;
3265     memcpy(im->rendered_image + im->rendered_image_size, data, length);
3266     im->rendered_image_size += length;
3267     return CAIRO_STATUS_SUCCESS;
3268 }
3269
3270 /* draw that picture thing ... */
3271 int graph_paint(
3272     image_desc_t *im)
3273 {
3274     int       i, ii;
3275     int       lazy = lazy_check(im);
3276     double    areazero = 0.0;
3277     graph_desc_t *lastgdes = NULL;
3278     rrd_infoval_t info;
3279
3280 //    PangoFontMap *font_map = pango_cairo_font_map_get_default();
3281
3282     /* pull the data from the rrd files ... */
3283     if (data_fetch(im) == -1)
3284         return -1;
3285     /* evaluate VDEF and CDEF operations ... */
3286     if (data_calc(im) == -1)
3287         return -1;
3288     /* calculate and PRINT and GPRINT definitions. We have to do it at
3289      * this point because it will affect the length of the legends
3290      * if there are no graph elements (i==0) we stop here ...
3291      * if we are lazy, try to quit ...
3292      */
3293     i = print_calc(im);
3294     if (i < 0)
3295         return -1;
3296
3297     /* if we want and can be lazy ... quit now */
3298     if (i == 0)
3299         return 0;
3300
3301 /**************************************************************
3302  *** Calculating sizes and locations became a bit confusing ***
3303  *** so I moved this into a separate function.              ***
3304  **************************************************************/
3305     if (graph_size_location(im, i) == -1)
3306         return -1;
3307
3308     info.u_cnt = im->xorigin;
3309     grinfo_push(im, sprintf_alloc("graph_left"), RD_I_CNT, info);
3310     info.u_cnt = im->yorigin - im->ysize;
3311     grinfo_push(im, sprintf_alloc("graph_top"), RD_I_CNT, info);
3312     info.u_cnt = im->xsize;
3313     grinfo_push(im, sprintf_alloc("graph_width"), RD_I_CNT, info);
3314     info.u_cnt = im->ysize;
3315     grinfo_push(im, sprintf_alloc("graph_height"), RD_I_CNT, info);
3316     info.u_cnt = im->ximg;
3317     grinfo_push(im, sprintf_alloc("image_width"), RD_I_CNT, info);
3318     info.u_cnt = im->yimg;
3319     grinfo_push(im, sprintf_alloc("image_height"), RD_I_CNT, info);
3320     info.u_cnt = im->start;
3321     grinfo_push(im, sprintf_alloc("graph_start"), RD_I_CNT, info);
3322     info.u_cnt = im->end;
3323     grinfo_push(im, sprintf_alloc("graph_end"), RD_I_CNT, info);
3324
3325     /* if we want and can be lazy ... quit now */
3326     if (lazy)
3327         return 0;
3328
3329     /* get actual drawing data and find min and max values */
3330     if (data_proc(im) == -1)
3331         return -1;
3332     if (!im->logarithmic) {
3333         si_unit(im);
3334     }
3335
3336     /* identify si magnitude Kilo, Mega Giga ? */
3337     if (!im->rigid && !im->logarithmic)
3338         expand_range(im);   /* make sure the upper and lower limit are
3339                                sensible values */
3340
3341     info.u_val = im->minval;
3342     grinfo_push(im, sprintf_alloc("value_min"), RD_I_VAL, info);
3343     info.u_val = im->maxval;
3344     grinfo_push(im, sprintf_alloc("value_max"), RD_I_VAL, info);
3345
3346
3347     if (!calc_horizontal_grid(im))
3348         return -1;
3349     /* reset precalc */
3350     ytr(im, DNAN);
3351 /*   if (im->gridfit)
3352      apply_gridfit(im); */
3353     /* the actual graph is created by going through the individual
3354        graph elements and then drawing them */
3355     cairo_surface_destroy(im->surface);
3356     switch (im->imgformat) {
3357     case IF_PNG:
3358         im->surface =
3359             cairo_image_surface_create(CAIRO_FORMAT_ARGB32,
3360                                        im->ximg * im->zoom,
3361                                        im->yimg * im->zoom);
3362         break;
3363     case IF_PDF:
3364         im->gridfit = 0;
3365         im->surface = strlen(im->graphfile)
3366             ? cairo_pdf_surface_create(im->graphfile, im->ximg * im->zoom,
3367                                        im->yimg * im->zoom)
3368             : cairo_pdf_surface_create_for_stream
3369             (&cairo_output, im, im->ximg * im->zoom, im->yimg * im->zoom);
3370         break;
3371     case IF_EPS:
3372         im->gridfit = 0;
3373         im->surface = strlen(im->graphfile)
3374             ?
3375             cairo_ps_surface_create(im->graphfile, im->ximg * im->zoom,
3376                                     im->yimg * im->zoom)
3377             : cairo_ps_surface_create_for_stream
3378             (&cairo_output, im, im->ximg * im->zoom, im->yimg * im->zoom);
3379         break;
3380     case IF_SVG:
3381         im->gridfit = 0;
3382         im->surface = strlen(im->graphfile)
3383             ?
3384             cairo_svg_surface_create(im->
3385                                      graphfile,
3386                                      im->ximg * im->zoom, im->yimg * im->zoom)
3387             : cairo_svg_surface_create_for_stream
3388             (&cairo_output, im, im->ximg * im->zoom, im->yimg * im->zoom);
3389         cairo_svg_surface_restrict_to_version
3390             (im->surface, CAIRO_SVG_VERSION_1_1);
3391         break;
3392     };
3393     cairo_destroy(im->cr);
3394     im->cr = cairo_create(im->surface);
3395     cairo_set_antialias(im->cr, im->graph_antialias);
3396     cairo_scale(im->cr, im->zoom, im->zoom);
3397 //    pango_cairo_font_map_set_resolution(PANGO_CAIRO_FONT_MAP(font_map), 100);
3398     gfx_new_area(im, 0, 0, 0, im->yimg,
3399             &nbs