libraries/gd1.3/webgif.c

   1 /* Bring in the gd library functions */
   2 #include "gd.h"
   3
   4 /* Bring in standard I/O and string manipulation functions */
   5 #include <stdio.h>
   6 #include <string.h>
   7
   8 int main(int argc, char **argv)
   9 {
  10         FILE *in;
  11         FILE *out;
  12         char outFn[20];
  13         int useStdinStdout=0;
  14
  15         /* Declare our image pointer */
  16         gdImagePtr im = 0;
  17         int i;
  18        /* We'll clear 'no' once we know the user has made a
  19                 reasonable request. */
  20         int no = 1;
  21         /* We'll set 'write' once we know the user's request
  22                 requires that the image be written back to disk. */
  23         int write = 0;
  24         /* C programs always get at least one argument; we want at
  25                 least one more (the image), more in practice. */
  26         if (argc < 2 || !strcmp(argv[1], "--help")) {
  27                 no = 1;
  28                 goto usage;
  29         }
  30
  31         /* The last argument should be the image. Open the file. */
  32         if (strcmp("-", argv[argc-1])==0) { /* - is synonymous with STDIN */
  33           useStdinStdout = 1;
  34           in = stdin;
  35         } else {
  36           in = fopen(argv[argc-1], "rb");
  37         }
  38         if (!in) {
  39                 fprintf(stderr,
  40                         "Error: can't open file %s.\n", argv[argc-1]);
  41                 exit(1);
  42         }
  43         /* Now load the image. */
  44         im = gdImageCreateFromGif(in);
  45         fclose(in);
  46         /* If the load failed, it must not be a GIF file. */
  47         if (!im) {
  48                 fprintf(stderr,
  49                         "Error: %s is not a valid gif file.\n", argv[argc-1]);
  50                 exit(1);
  51         }
  52         /* Consider each argument in turn. */
  53         for (i=1; (i < (argc-1)); i++) {
  54                 /* -i turns on and off interlacing. */
  55                 if (!strcmp(argv[i], "--help")) {
  56                   /* Every program should use this for help! :) */
  57                   no = 1;
  58                   goto usage;
  59                 } else if (!strcmp(argv[i], "-i")) {
  60                         if (i == (argc-2)) {
  61                                 fprintf(stderr,
  62                                 "Error: -i specified without y or n.\n");
  63                                 no = 1;
  64                                 goto usage;
  65                         }
  66                         if (!strcmp(argv[i+1], "y")) {
  67                                 /* Set interlace. */
  68                                 gdImageInterlace(im, 1);
  69                         } else if (!strcmp(argv[i+1], "n")) {
  70                                 /* Clear interlace. */
  71                                 gdImageInterlace(im, 0);
  72                         } else {
  73                                 fprintf(stderr,
  74                                 "Error: -i specified without y or n.\n");
  75                                 no = 1;
  76                                 goto usage;
  77                         }
  78                         i++;
  79                         no = 0;
  80                         write = 1;
  81                 } else if (!strcmp(argv[i], "-t")) {
  82                         /* Set transparent index (or none). */
  83                         int index;
  84                         if (i == (argc-2)) {
  85                                 fprintf(stderr,
  86                 "Error: -t specified without a color table index.\n");
  87                                 no = 1;
  88                                 goto usage;
  89                         }
  90                         if (!strcmp(argv[i+1], "none")) {
  91                                 /* -1 means not transparent. */
  92                                 gdImageColorTransparent(im, -1);
  93                         } else {
  94                                 /* OK, get an integer and set the index. */
  95                                 index = atoi(argv[i+1]);
  96                                 gdImageColorTransparent(im, index);
  97                         }
  98                         i++;
  99                         write = 1;
 100                         no = 0;
 101                 } else if (!strcmp(argv[i], "-l")) {
 102                         /* List the colors in the color table. */
 103                         int j;
 104                         /* Tabs used below. */
 105                         printf("Index   Red     Green   Blue\n");
 106                         for (j=0; (j < gdImageColorsTotal(im)); j++) {
 107                                 /* Use access macros to learn colors. */
 108                                 printf("%d      %d      %d      %d\n",
 109                                         j,
 110                                         gdImageRed(im, j),
 111                                         gdImageGreen(im, j),
 112                                         gdImageBlue(im, j));
 113                         }
 114                         no = 0;
 115                 } else if (!strcmp(argv[i], "-d")) {
 116                         /* Output dimensions, etc. */
 117                         int t;
 118                         printf("Width: %d Height: %d Colors: %d\n",
 119                                 gdImageSX(im), gdImageSY(im),
 120                                 gdImageColorsTotal(im));
 121                         t = gdImageGetTransparent(im);
 122                         if (t != (-1)) {
 123                                 printf("Transparent index: %d\n", t);
 124                         } else {
 125                                 /* -1 means the image is not transparent. */
 126                                 printf("Transparent index: none\n");
 127                         }
 128                         if (gdImageGetInterlaced(im)) {
 129                                 printf("Interlaced: yes\n");
 130                         } else {
 131                                 printf("Interlaced: no\n");
 132                         }
 133                         no = 0;
 134                 } else {
 135                         fprintf(stderr, "Unknown argument: %s\n", argv[i]);
 136                         break;
 137                 }
 138         }
 139 usage:
 140         if (no) {
 141                 /* If the command failed, output an explanation. */
 142                 fprintf(stderr,
 143 "Usage: webgif [-i y|n ] [-l] [-t index|off ] [-d] gifname.gif\n"
 144
 145 "  -i [y|n]   Turns on/off interlace\n"
 146 "  -l         Prints the table of color indexes\n"
 147 "  -t [index] Set the transparent color to the specified index (0-255 or none)\n"
 148 "  -d         Reports the dimensions and other characteristics of the image.\n"
 149 "\n"
 150 "If you specify '-' as the input file, stdin/stdout will be used input/output.\n"
 151 );
 152         }
 153         if (write) {
 154           if (useStdinStdout) {
 155             out = stdout;
 156           } else {
 157             /* Open a temporary file. */
 158
 159             /* "temp.tmp" is not good temporary filename. */
 160             sprintf(outFn, "webgif.tmp%d", getpid());
 161             out = fopen(outFn, "wb");
 162
 163             if (!out) {
 164               fprintf(stderr,
 165                       "Unable to write to %s -- exiting\n", outFn);
 166               exit(1);
 167             }
 168           }
 169
 170           /* Write the new gif. */
 171           gdImageGif(im, out);
 172
 173           if (!useStdinStdout) {
 174             fclose(out);
 175             /* Erase the old gif. */
 176             unlink(argv[argc-1]);
 177             /* Rename the new to the old. */
 178             if (rename(outFn, argv[argc-1])!=0) {
 179               perror("rename");
 180               exit(1);
 181             }
 182           }
 183         }
 184         /* Delete the image from memory. */
 185         if (im) {
 186                 gdImageDestroy(im);
 187         }
 188         /* All's well that ends well. */
 189         return 0;
 190 }
 191