src/battery.c

   1 /**
   2  * collectd - src/battery.c
   3  * Copyright (C) 2006-2014  Florian octo Forster
   4  * Copyright (C) 2008       Michał Mirosław
   5  * Copyright (C) 2014       Andy Parkins
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; only version 2 of the License is applicable.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  19  *
  20  * Authors:
  21  *   Florian octo Forster <octo at collectd.org>
  22  *   Michał Mirosław <mirq-linux at rere.qmqm.pl>
  23  *   Andy Parkins <andyp at fussylogic.co.uk>
  24  **/
  25
  26 #include "collectd.h"
  27
  28 #include "common.h"
  29 #include "plugin.h"
  30
  31 #if HAVE_MACH_MACH_TYPES_H
  32 #  include <mach/mach_types.h>
  33 #endif
  34 #if HAVE_MACH_MACH_INIT_H
  35 #  include <mach/mach_init.h>
  36 #endif
  37 #if HAVE_MACH_MACH_ERROR_H
  38 #  include <mach/mach_error.h>
  39 #endif
  40 #if HAVE_COREFOUNDATION_COREFOUNDATION_H
  41 #  include <CoreFoundation/CoreFoundation.h>
  42 #endif
  43 #if HAVE_IOKIT_IOKITLIB_H
  44 #  include <IOKit/IOKitLib.h>
  45 #endif
  46 #if HAVE_IOKIT_IOTYPES_H
  47 #  include <IOKit/IOTypes.h>
  48 #endif
  49 #if HAVE_IOKIT_PS_IOPOWERSOURCES_H
  50 #  include <IOKit/ps/IOPowerSources.h>
  51 #endif
  52 #if HAVE_IOKIT_PS_IOPSKEYS_H
  53 #  include <IOKit/ps/IOPSKeys.h>
  54 #endif
  55
  56 #if !HAVE_IOKIT_IOKITLIB_H && !HAVE_IOKIT_PS_IOPOWERSOURCES_H && !KERNEL_LINUX
  57 # error "No applicable input method."
  58 #endif
  59
  60 #if HAVE_IOKIT_IOKITLIB_H || HAVE_IOKIT_PS_IOPOWERSOURCES_H
  61         /* No global variables */
  62 /* #endif HAVE_IOKIT_IOKITLIB_H || HAVE_IOKIT_PS_IOPOWERSOURCES_H */
  63
  64 #elif KERNEL_LINUX
  65 # define PROC_PMU_PATH_FORMAT "/proc/pmu/battery_%i"
  66 # define PROC_ACPI_PATH "/proc/acpi/battery"
  67 # define PROC_ACPI_FACTOR 0.001
  68 # define SYSFS_PATH "/sys/class/power_supply"
  69 # define SYSFS_FACTOR 0.000001
  70 #endif /* KERNEL_LINUX */
  71
  72 int battery_read_statefs (void); /* defined in battery_statefs; used by StateFS backend */
  73
  74 static _Bool report_percent = 0;
  75 static _Bool report_degraded = 0;
  76 static _Bool query_statefs = 0;
  77
  78 static void battery_submit2 (char const *plugin_instance, /* {{{ */
  79                 char const *type, char const *type_instance, gauge_t value)
  80 {
  81         value_t values[1];
  82         value_list_t vl = VALUE_LIST_INIT;
  83
  84         values[0].gauge = value;
  85
  86         vl.values = values;
  87         vl.values_len = 1;
  88         sstrncpy (vl.host, hostname_g, sizeof (vl.host));
  89         sstrncpy (vl.plugin, "battery", sizeof (vl.plugin));
  90         sstrncpy (vl.plugin_instance, plugin_instance, sizeof (vl.plugin_instance));
  91         sstrncpy (vl.type, type, sizeof (vl.type));
  92         if (type_instance != NULL)
  93                 sstrncpy (vl.type_instance, type_instance, sizeof (vl.type_instance));
  94
  95         plugin_dispatch_values (&vl);
  96 } /* }}} void battery_submit2 */
  97
  98 static void battery_submit (char const *plugin_instance, /* {{{ */
  99                 char const *type, gauge_t value)
 100 {
 101         battery_submit2 (plugin_instance, type, NULL, value);
 102 } /* }}} void battery_submit */
 103
 104 static void submit_capacity (char const *plugin_instance, /* {{{ */
 105                 gauge_t capacity_charged,
 106                 gauge_t capacity_full,
 107                 gauge_t capacity_design)
 108 {
 109         if (report_percent && (capacity_charged > capacity_full))
 110                 return;
 111         if (report_degraded && (capacity_full > capacity_design))
 112                 return;
 113
 114         if (report_percent)
 115         {
 116                 gauge_t capacity_max;
 117
 118                 if (report_degraded)
 119                         capacity_max = capacity_design;
 120                 else
 121                         capacity_max = capacity_full;
 122
 123                 battery_submit2 (plugin_instance, "percent", "charged",
 124                                 100.0 * capacity_charged / capacity_max);
 125                 battery_submit2 (plugin_instance, "percent", "discharged",
 126                                 100.0 * (capacity_full - capacity_charged) / capacity_max);
 127
 128                 if (report_degraded)
 129                         battery_submit2 (plugin_instance, "percent", "degraded",
 130                                         100.0 * (capacity_design - capacity_full) / capacity_max);
 131         }
 132         else if (report_degraded) /* && !report_percent */
 133         {
 134                 battery_submit2 (plugin_instance, "capacity", "charged",
 135                                 capacity_charged);
 136                 battery_submit2 (plugin_instance, "capacity", "discharged",
 137                                 (capacity_full - capacity_charged));
 138                 battery_submit2 (plugin_instance, "capacity", "degraded",
 139                                 (capacity_design - capacity_full));
 140         }
 141         else /* !report_percent && !report_degraded */
 142         {
 143                 battery_submit (plugin_instance, "capacity", capacity_charged);
 144         }
 145 } /* }}} void submit_capacity */
 146
 147 #if HAVE_IOKIT_PS_IOPOWERSOURCES_H || HAVE_IOKIT_IOKITLIB_H
 148 static double dict_get_double (CFDictionaryRef dict, const char *key_string) /* {{{ */
 149 {
 150         double      val_double;
 151         long long   val_int;
 152         CFNumberRef val_obj;
 153         CFStringRef key_obj;
 154
 155         key_obj = CFStringCreateWithCString (kCFAllocatorDefault, key_string,
 156                         kCFStringEncodingASCII);
 157         if (key_obj == NULL)
 158         {
 159                 DEBUG ("CFStringCreateWithCString (%s) failed.\n", key_string);
 160                 return (NAN);
 161         }
 162
 163         if ((val_obj = CFDictionaryGetValue (dict, key_obj)) == NULL)
 164         {
 165                 DEBUG ("CFDictionaryGetValue (%s) failed.", key_string);
 166                 CFRelease (key_obj);
 167                 return (NAN);
 168         }
 169         CFRelease (key_obj);
 170
 171         if (CFGetTypeID (val_obj) == CFNumberGetTypeID ())
 172         {
 173                 if (CFNumberIsFloatType (val_obj))
 174                 {
 175                         CFNumberGetValue (val_obj,
 176                                         kCFNumberDoubleType,
 177                                         &val_double);
 178                 }
 179                 else
 180                 {
 181                         CFNumberGetValue (val_obj,
 182                                         kCFNumberLongLongType,
 183                                         &val_int);
 184                         val_double = val_int;
 185                 }
 186         }
 187         else
 188         {
 189                 DEBUG ("CFGetTypeID (val_obj) = %i", (int) CFGetTypeID (val_obj));
 190                 return (NAN);
 191         }
 192
 193         return (val_double);
 194 } /* }}} double dict_get_double */
 195
 196 # if HAVE_IOKIT_PS_IOPOWERSOURCES_H
 197 static void get_via_io_power_sources (double *ret_charge, /* {{{ */
 198                 double *ret_current,
 199                 double *ret_voltage)
 200 {
 201         CFTypeRef       ps_raw;
 202         CFArrayRef      ps_array;
 203         int             ps_array_len;
 204         CFDictionaryRef ps_dict;
 205         CFTypeRef       ps_obj;
 206
 207         double temp_double;
 208
 209         ps_raw       = IOPSCopyPowerSourcesInfo ();
 210         ps_array     = IOPSCopyPowerSourcesList (ps_raw);
 211         ps_array_len = CFArrayGetCount (ps_array);
 212
 213         DEBUG ("ps_array_len == %i", ps_array_len);
 214
 215         for (int i = 0; i < ps_array_len; i++)
 216         {
 217                 ps_obj  = CFArrayGetValueAtIndex (ps_array, i);
 218                 ps_dict = IOPSGetPowerSourceDescription (ps_raw, ps_obj);
 219
 220                 if (ps_dict == NULL)
 221                 {
 222                         DEBUG ("IOPSGetPowerSourceDescription failed.");
 223                         continue;
 224                 }
 225
 226                 if (CFGetTypeID (ps_dict) != CFDictionaryGetTypeID ())
 227                 {
 228                         DEBUG ("IOPSGetPowerSourceDescription did not return a CFDictionaryRef");
 229                         continue;
 230                 }
 231
 232                 /* FIXME: Check if this is really an internal battery */
 233
 234                 if (isnan (*ret_charge))
 235                 {
 236                         /* This is the charge in percent. */
 237                         temp_double = dict_get_double (ps_dict,
 238                                         kIOPSCurrentCapacityKey);
 239                         if (!isnan ((temp_double))
 240                                         && (temp_double >= 0.0)
 241                                         && (temp_double <= 100.0))
 242                                 *ret_charge = temp_double;
 243                 }
 244
 245                 if (isnan (*ret_current))
 246                 {
 247                         temp_double = dict_get_double (ps_dict,
 248                                         kIOPSCurrentKey);
 249                         if (!isnan (temp_double))
 250                                 *ret_current = temp_double / 1000.0;
 251                 }
 252
 253                 if (isnan (*ret_voltage))
 254                 {
 255                         temp_double = dict_get_double (ps_dict,
 256                                         kIOPSVoltageKey);
 257                         if (!isnan (temp_double))
 258                                 *ret_voltage = temp_double / 1000.0;
 259                 }
 260         }
 261
 262         CFRelease(ps_array);
 263         CFRelease(ps_raw);
 264 } /* }}} void get_via_io_power_sources */
 265 # endif /* HAVE_IOKIT_PS_IOPOWERSOURCES_H */
 266
 267 # if HAVE_IOKIT_IOKITLIB_H
 268 static void get_via_generic_iokit (double *ret_capacity_full, /* {{{ */
 269                 double *ret_capacity_design,
 270                 double *ret_current,
 271                 double *ret_voltage)
 272 {
 273         kern_return_t   status;
 274         io_iterator_t   iterator;
 275         io_object_t     io_obj;
 276
 277         CFDictionaryRef bat_root_dict;
 278         CFArrayRef      bat_info_arry;
 279         CFIndex         bat_info_arry_len;
 280         CFDictionaryRef bat_info_dict;
 281
 282         double temp_double;
 283
 284         status = IOServiceGetMatchingServices (kIOMasterPortDefault,
 285                         IOServiceNameMatching ("battery"),
 286                         &iterator);
 287         if (status != kIOReturnSuccess)
 288         {
 289                 DEBUG ("IOServiceGetMatchingServices failed.");
 290                 return;
 291         }
 292
 293         while ((io_obj = IOIteratorNext (iterator)))
 294         {
 295                 status = IORegistryEntryCreateCFProperties (io_obj,
 296                                 (CFMutableDictionaryRef *) &bat_root_dict,
 297                                 kCFAllocatorDefault,
 298                                 kNilOptions);
 299                 if (status != kIOReturnSuccess)
 300                 {
 301                         DEBUG ("IORegistryEntryCreateCFProperties failed.");
 302                         continue;
 303                 }
 304
 305                 bat_info_arry = (CFArrayRef) CFDictionaryGetValue (bat_root_dict,
 306                                 CFSTR ("IOBatteryInfo"));
 307                 if (bat_info_arry == NULL)
 308                 {
 309                         CFRelease (bat_root_dict);
 310                         continue;
 311                 }
 312                 bat_info_arry_len = CFArrayGetCount (bat_info_arry);
 313
 314                 for (CFIndex bat_info_arry_pos = 0;
 315                                 bat_info_arry_pos < bat_info_arry_len;
 316                                 bat_info_arry_pos++)
 317                 {
 318                         bat_info_dict = (CFDictionaryRef) CFArrayGetValueAtIndex (bat_info_arry, bat_info_arry_pos);
 319
 320                         if (isnan (*ret_capacity_full))
 321                         {
 322                                 temp_double = dict_get_double (bat_info_dict, "Capacity");
 323                                 *ret_capacity_full = temp_double / 1000.0;
 324                         }
 325
 326                         if (isnan (*ret_capacity_design))
 327                         {
 328                                 temp_double = dict_get_double (bat_info_dict, "AbsoluteMaxCapacity");
 329                                 *ret_capacity_design = temp_double / 1000.0;
 330                         }
 331
 332                         if (isnan (*ret_current))
 333                         {
 334                                 temp_double = dict_get_double (bat_info_dict, "Current");
 335                                 *ret_current = temp_double / 1000.0;
 336                         }
 337
 338                         if (isnan (*ret_voltage))
 339                         {
 340                                 temp_double = dict_get_double (bat_info_dict, "Voltage");
 341                                 *ret_voltage = temp_double / 1000.0;
 342                         }
 343                 }
 344
 345                 CFRelease (bat_root_dict);
 346         }
 347
 348         IOObjectRelease (iterator);
 349 } /* }}} void get_via_generic_iokit */
 350 # endif /* HAVE_IOKIT_IOKITLIB_H */
 351
 352 static int battery_read (void) /* {{{ */
 353 {
 354         gauge_t current = NAN; /* Current in A */
 355         gauge_t voltage = NAN; /* Voltage in V */
 356
 357         /* We only get the charged capacity as a percentage from
 358          * IOPowerSources. IOKit, on the other hand, only reports the full
 359          * capacity. We use the two to calculate the current charged capacity. */
 360         gauge_t charge_rel = NAN; /* Current charge in percent */
 361         gauge_t capacity_charged; /* Charged capacity */
 362         gauge_t capacity_full = NAN; /* Total capacity */
 363         gauge_t capacity_design = NAN; /* Full design capacity */
 364
 365         if (query_statefs)
 366                 return battery_read_statefs ();
 367
 368 #if HAVE_IOKIT_PS_IOPOWERSOURCES_H
 369         get_via_io_power_sources (&charge_rel, &current, &voltage);
 370 #endif
 371 #if HAVE_IOKIT_IOKITLIB_H
 372         get_via_generic_iokit (&capacity_full, &capacity_design, &current, &voltage);
 373 #endif
 374
 375         capacity_charged = charge_rel * capacity_full / 100.0;
 376         submit_capacity ("0", capacity_charged, capacity_full, capacity_design);
 377
 378         if (!isnan (current))
 379                 battery_submit ("0", "current", current);
 380         if (!isnan (voltage))
 381                 battery_submit ("0", "voltage", voltage);
 382
 383         return (0);
 384 } /* }}} int battery_read */
 385 /* #endif HAVE_IOKIT_IOKITLIB_H || HAVE_IOKIT_PS_IOPOWERSOURCES_H */
 386
 387 #elif KERNEL_LINUX
 388 /* Reads a file which contains only a number (and optionally a trailing
 389  * newline) and parses that number. */
 390 static int sysfs_file_to_buffer(char const *dir, /* {{{ */
 391                 char const *power_supply,
 392                 char const *basename,
 393                 char *buffer, size_t buffer_size)
 394 {
 395         char filename[PATH_MAX];
 396         int status;
 397
 398         ssnprintf (filename, sizeof (filename), "%s/%s/%s",
 399                         dir, power_supply, basename);
 400
 401         status = (int) read_file_contents (filename, buffer, buffer_size);
 402         if (status < 0)
 403                 return status;
 404
 405         strstripnewline (buffer);
 406         return 0;
 407 } /* }}} int sysfs_file_to_buffer */
 408
 409 /* Reads a file which contains only a number (and optionally a trailing
 410  * newline) and parses that number. */
 411 static int sysfs_file_to_gauge(char const *dir, /* {{{ */
 412                 char const *power_supply,
 413                 char const *basename, gauge_t *ret_value)
 414 {
 415         int status;
 416         char buffer[32] = "";
 417
 418         status = sysfs_file_to_buffer (dir, power_supply, basename, buffer, sizeof (buffer));
 419         if (status != 0)
 420                 return (status);
 421
 422         return (strtogauge (buffer, ret_value));
 423 } /* }}} sysfs_file_to_gauge */
 424
 425 static int read_sysfs_capacity (char const *dir, /* {{{ */
 426                 char const *power_supply,
 427                 char const *plugin_instance)
 428 {
 429         gauge_t capacity_charged = NAN;
 430         gauge_t capacity_full = NAN;
 431         gauge_t capacity_design = NAN;
 432         int status;
 433
 434         status = sysfs_file_to_gauge (dir, power_supply, "energy_now", &capacity_charged);
 435         if (status != 0)
 436                 return (status);
 437
 438         status = sysfs_file_to_gauge (dir, power_supply, "energy_full", &capacity_full);
 439         if (status != 0)
 440                 return (status);
 441
 442         status = sysfs_file_to_gauge (dir, power_supply, "energy_full_design", &capacity_design);
 443         if (status != 0)
 444                 return (status);
 445
 446         submit_capacity (plugin_instance,
 447                         capacity_charged * SYSFS_FACTOR,
 448                         capacity_full * SYSFS_FACTOR,
 449                         capacity_design * SYSFS_FACTOR);
 450         return (0);
 451 } /* }}} int read_sysfs_capacity */
 452
 453 static int read_sysfs_callback (char const *dir, /* {{{ */
 454                 char const *power_supply,
 455                 void *user_data)
 456 {
 457         int *battery_index = user_data;
 458
 459         char const *plugin_instance;
 460         char buffer[32];
 461         gauge_t v = NAN;
 462         _Bool discharging = 0;
 463         int status;
 464
 465         /* Ignore non-battery directories, such as AC power. */
 466         status = sysfs_file_to_buffer (dir, power_supply, "type", buffer, sizeof (buffer));
 467         if (status != 0)
 468                 return (0);
 469         if (strcasecmp ("Battery", buffer) != 0)
 470                 return (0);
 471
 472         (void) sysfs_file_to_buffer (dir, power_supply, "status", buffer, sizeof (buffer));
 473         if (strcasecmp ("Discharging", buffer) == 0)
 474                 discharging = 1;
 475
 476         /* FIXME: This is a dirty hack for backwards compatibility: The battery
 477          * plugin, for a very long time, has had the plugin_instance
 478          * hard-coded to "0". So, to keep backwards compatibility, we'll use
 479          * "0" for the first battery we find and the power_supply name for all
 480          * following. This should be reverted in a future major version. */
 481         plugin_instance = (*battery_index == 0) ? "0" : power_supply;
 482         (*battery_index)++;
 483
 484         read_sysfs_capacity (dir, power_supply, plugin_instance);
 485
 486         if (sysfs_file_to_gauge (dir, power_supply, "power_now", &v) == 0)
 487         {
 488                 if (discharging)
 489                         v *= -1.0;
 490                 battery_submit (plugin_instance, "power", v * SYSFS_FACTOR);
 491         }
 492         if (sysfs_file_to_gauge (dir, power_supply, "current_now", &v) == 0)
 493         {
 494                 if (discharging)
 495                         v *= -1.0;
 496                 battery_submit (plugin_instance, "current", v * SYSFS_FACTOR);
 497         }
 498
 499         if (sysfs_file_to_gauge (dir, power_supply, "voltage_now", &v) == 0)
 500                 battery_submit (plugin_instance, "voltage", v * SYSFS_FACTOR);
 501
 502         return (0);
 503 } /* }}} int read_sysfs_callback */
 504
 505 static int read_sysfs (void) /* {{{ */
 506 {
 507         int status;
 508         int battery_counter = 0;
 509
 510         if (access (SYSFS_PATH, R_OK) != 0)
 511                 return (ENOENT);
 512
 513         status = walk_directory (SYSFS_PATH, read_sysfs_callback,
 514                         /* user_data = */ &battery_counter,
 515                         /* include hidden */ 0);
 516         return (status);
 517 } /* }}} int read_sysfs */
 518
 519 static int read_acpi_full_capacity (char const *dir, /* {{{ */
 520                 char const *power_supply,
 521                 gauge_t *ret_capacity_full,
 522                 gauge_t *ret_capacity_design)
 523
 524 {
 525         char filename[PATH_MAX];
 526         char buffer[1024];
 527
 528         FILE *fh;
 529
 530         ssnprintf (filename, sizeof (filename), "%s/%s/info", dir, power_supply);
 531         fh = fopen (filename, "r");
 532         if (fh == NULL)
 533                 return (errno);
 534
 535         /* last full capacity:      40090 mWh */
 536         while (fgets (buffer, sizeof (buffer), fh) != NULL)
 537         {
 538                 gauge_t *value_ptr;
 539                 int fields_num;
 540                 char *fields[8];
 541                 int index;
 542
 543                 if (strncmp ("last full capacity:", buffer, strlen ("last full capacity:")) == 0)
 544                 {
 545                         value_ptr = ret_capacity_full;
 546                         index = 3;
 547                 }
 548                 else if (strncmp ("design capacity:", buffer, strlen ("design capacity:")) == 0)
 549                 {
 550                         value_ptr = ret_capacity_design;
 551                         index = 2;
 552                 }
 553                 else
 554                 {
 555                         continue;
 556                 }
 557
 558                 fields_num = strsplit (buffer, fields, STATIC_ARRAY_SIZE (fields));
 559                 if (fields_num <= index)
 560                         continue;
 561
 562                 strtogauge (fields[index], value_ptr);
 563         }
 564
 565         fclose (fh);
 566         return (0);
 567 } /* }}} int read_acpi_full_capacity */
 568
 569 static int read_acpi_callback (char const *dir, /* {{{ */
 570                 char const *power_supply,
 571                 void *user_data)
 572 {
 573         int *battery_index = user_data;
 574
 575         gauge_t power = NAN;
 576         gauge_t voltage = NAN;
 577         gauge_t capacity_charged = NAN;
 578         gauge_t capacity_full = NAN;
 579         gauge_t capacity_design = NAN;
 580         _Bool charging = 0;
 581         _Bool is_current = 0;
 582
 583         char const *plugin_instance;
 584         char filename[PATH_MAX];
 585         char buffer[1024];
 586
 587         FILE *fh;
 588
 589         ssnprintf (filename, sizeof (filename), "%s/%s/state", dir, power_supply);
 590         fh = fopen (filename, "r");
 591         if (fh == NULL)
 592         {
 593                 if ((errno == EAGAIN) || (errno == EINTR) || (errno == ENOENT))
 594                         return (0);
 595                 else
 596                         return (errno);
 597         }
 598
 599         /*
 600          * [11:00] <@tokkee> $ cat /proc/acpi/battery/BAT1/state
 601          * [11:00] <@tokkee> present:                 yes
 602          * [11:00] <@tokkee> capacity state:          ok
 603          * [11:00] <@tokkee> charging state:          charging
 604          * [11:00] <@tokkee> present rate:            1724 mA
 605          * [11:00] <@tokkee> remaining capacity:      4136 mAh
 606          * [11:00] <@tokkee> present voltage:         12428 mV
 607          */
 608         while (fgets (buffer, sizeof (buffer), fh) != NULL)
 609         {
 610                 char *fields[8];
 611                 int numfields;
 612
 613                 numfields = strsplit (buffer, fields, STATIC_ARRAY_SIZE (fields));
 614                 if (numfields < 3)
 615                         continue;
 616
 617                 if ((strcmp (fields[0], "charging") == 0)
 618                                 && (strcmp (fields[1], "state:") == 0))
 619                 {
 620                         if (strcmp (fields[2], "charging") == 0)
 621                                 charging = 1;
 622                         else
 623                                 charging = 0;
 624                         continue;
 625                 }
 626
 627                 /* The unit of "present rate" depends on the battery. Modern
 628                  * batteries export power (watts), older batteries (used to)
 629                  * export current (amperes). We check the fourth column and try
 630                  * to find old batteries this way. */
 631                 if ((strcmp (fields[0], "present") == 0)
 632                                 && (strcmp (fields[1], "rate:") == 0))
 633                 {
 634                         strtogauge (fields[2], &power);
 635
 636                         if ((numfields >= 4) && (strcmp ("mA", fields[3]) == 0))
 637                                 is_current = 1;
 638                 }
 639                 else if ((strcmp (fields[0], "remaining") == 0)
 640                                 && (strcmp (fields[1], "capacity:") == 0))
 641                         strtogauge (fields[2], &capacity_charged);
 642                 else if ((strcmp (fields[0], "present") == 0)
 643                                 && (strcmp (fields[1], "voltage:") == 0))
 644                         strtogauge (fields[2], &voltage);
 645         } /* while (fgets (buffer, sizeof (buffer), fh) != NULL) */
 646
 647         fclose (fh);
 648
 649         if (!charging)
 650                 power *= -1.0;
 651
 652         /* FIXME: This is a dirty hack for backwards compatibility: The battery
 653          * plugin, for a very long time, has had the plugin_instance
 654          * hard-coded to "0". So, to keep backwards compatibility, we'll use
 655          * "0" for the first battery we find and the power_supply name for all
 656          * following. This should be reverted in a future major version. */
 657         plugin_instance = (*battery_index == 0) ? "0" : power_supply;
 658         (*battery_index)++;
 659
 660         read_acpi_full_capacity (dir, power_supply, &capacity_full, &capacity_design);
 661
 662         submit_capacity (plugin_instance,
 663                         capacity_charged * PROC_ACPI_FACTOR,
 664                         capacity_full * PROC_ACPI_FACTOR,
 665                         capacity_design * PROC_ACPI_FACTOR);
 666
 667         battery_submit (plugin_instance,
 668                         is_current ? "current" : "power",
 669                         power * PROC_ACPI_FACTOR);
 670         battery_submit (plugin_instance, "voltage", voltage * PROC_ACPI_FACTOR);
 671
 672         return 0;
 673 } /* }}} int read_acpi_callback */
 674
 675 static int read_acpi (void) /* {{{ */
 676 {
 677         int status;
 678         int battery_counter = 0;
 679
 680         if (access (PROC_ACPI_PATH, R_OK) != 0)
 681                 return (ENOENT);
 682
 683         status = walk_directory (PROC_ACPI_PATH, read_acpi_callback,
 684                         /* user_data = */ &battery_counter,
 685                         /* include hidden */ 0);
 686         return (status);
 687 } /* }}} int read_acpi */
 688
 689 static int read_pmu (void) /* {{{ */
 690 {
 691         int i = 0;
 692         /* The upper limit here is just a safeguard. If there is a system with
 693          * more than 100 batteries, this can easily be increased. */
 694         for (; i < 100; i++)
 695         {
 696                 FILE *fh;
 697
 698                 char buffer[1024];
 699                 char filename[PATH_MAX];
 700                 char plugin_instance[DATA_MAX_NAME_LEN];
 701
 702                 gauge_t current = NAN;
 703                 gauge_t voltage = NAN;
 704                 gauge_t charge  = NAN;
 705
 706                 ssnprintf (filename, sizeof (filename), PROC_PMU_PATH_FORMAT, i);
 707                 if (access (filename, R_OK) != 0)
 708                         break;
 709
 710                 ssnprintf (plugin_instance, sizeof (plugin_instance), "%i", i);
 711
 712                 fh = fopen (filename, "r");
 713                 if (fh == NULL)
 714                 {
 715                         if (errno == ENOENT)
 716                                 break;
 717                         else if ((errno == EAGAIN) || (errno == EINTR))
 718                                 continue;
 719                         else
 720                                 return (errno);
 721                 }
 722
 723                 while (fgets (buffer, sizeof (buffer), fh) != NULL)
 724                 {
 725                         char *fields[8];
 726                         int numfields;
 727
 728                         numfields = strsplit (buffer, fields, STATIC_ARRAY_SIZE (fields));
 729                         if (numfields < 3)
 730                                 continue;
 731
 732                         if (strcmp ("current", fields[0]) == 0)
 733                                 strtogauge (fields[2], &current);
 734                         else if (strcmp ("voltage", fields[0]) == 0)
 735                                 strtogauge (fields[2], &voltage);
 736                         else if (strcmp ("charge", fields[0]) == 0)
 737                                 strtogauge (fields[2], &charge);
 738                 }
 739
 740                 fclose (fh);
 741                 fh = NULL;
 742
 743                 battery_submit (plugin_instance, "charge", charge / 1000.0);
 744                 battery_submit (plugin_instance, "current", current / 1000.0);
 745                 battery_submit (plugin_instance, "voltage", voltage / 1000.0);
 746         }
 747
 748         if (i == 0)
 749                 return (ENOENT);
 750         return (0);
 751 } /* }}} int read_pmu */
 752
 753 static int battery_read (void) /* {{{ */
 754 {
 755         int status;
 756
 757         if (query_statefs)
 758                 return battery_read_statefs ();
 759
 760         DEBUG ("battery plugin: Trying sysfs ...");
 761         status = read_sysfs ();
 762         if (status == 0)
 763                 return (0);
 764
 765         DEBUG ("battery plugin: Trying acpi ...");
 766         status = read_acpi ();
 767         if (status == 0)
 768                 return (0);
 769
 770         DEBUG ("battery plugin: Trying pmu ...");
 771         status = read_pmu ();
 772         if (status == 0)
 773                 return (0);
 774
 775         ERROR ("battery plugin: Add available input methods failed.");
 776         return (-1);
 777 } /* }}} int battery_read */
 778 #endif /* KERNEL_LINUX */
 779
 780 static int battery_config (oconfig_item_t *ci)
 781 {
 782         for (int i = 0; i < ci->children_num; i++)
 783         {
 784                 oconfig_item_t *child = ci->children + i;
 785
 786                 if (strcasecmp ("ValuesPercentage", child->key) == 0)
 787                         cf_util_get_boolean (child, &report_percent);
 788                 else if (strcasecmp ("ReportDegraded", child->key) == 0)
 789                         cf_util_get_boolean (child, &report_degraded);
 790                 else if (strcasecmp ("QueryStateFS", child->key) == 0)
 791                         cf_util_get_boolean (child, &query_statefs);
 792                 else
 793                         WARNING ("battery plugin: Ignoring unknown "
 794                                         "configuration option \"%s\".",
 795                                         child->key);
 796         }
 797
 798         return (0);
 799 } /* }}} int battery_config */
 800
 801 void module_register (void)
 802 {
 803         plugin_register_complex_config ("battery", battery_config);
 804         plugin_register_read ("battery", battery_read);
 805 } /* void module_register */