Dogcows Code - chaz/openbox/blob - obt/ddparse.c

   1 /* -*- indent-tabs-mode: nil; tab-width: 4; c-basic-offset: 4; -*-
   2
   3    obt/ddparse.c for the Openbox window manager
   4    Copyright (c) 2009        Dana Jansens
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    See the COPYING file for a copy of the GNU General Public License.
  17 */
  18
  19 #include "obt/ddparse.h"
  20 #include "obt/link.h"
  21 #ifdef HAVE_STRING_H
  22 #include <string.h>
  23 #endif
  24 #ifdef HAVE_STDIO_H
  25 #include <stdio.h>
  26 #endif
  27
  28 typedef struct _ObtDDParse ObtDDParse;
  29
  30 /* Parses the value and adds it to the group's key_hash, with the given
  31    key
  32    Return TRUE if it is added to the hash table, and FALSE if not.
  33 */
  34 typedef gboolean (*ObtDDParseValueFunc)(gchar *key, const gchar *val,
  35                                         ObtDDParse *parse, gboolean *error);
  36
  37
  38 struct _ObtDDParse {
  39     gchar *filename;
  40     gulong lineno;
  41     ObtDDParseGroup *group;
  42     /* the key is a group name, the value is a ObtDDParseGroup */
  43     GHashTable *group_hash;
  44 };
  45
  46 struct _ObtDDParseGroup {
  47     gchar *name;
  48     gboolean seen;
  49     ObtDDParseValueFunc value_func;
  50     /* the key is a string (a key inside the group in the .desktop).
  51        the value is an ObtDDParseValue */
  52     GHashTable *key_hash;
  53 };
  54
  55 /* Displays a warning message including the file name and line number, and
  56    sets the boolean @error to true if it points to a non-NULL address.
  57 */
  58 static void parse_error(const gchar *m, const ObtDDParse *const parse,
  59                         gboolean *error)
  60 {
  61     if (!parse->filename)
  62         g_warning("%s at line %lu of input", m, parse->lineno);
  63     else
  64         g_warning("%s at line %lu of file %s",
  65                   m, parse->lineno, parse->filename);
  66     if (error) *error = TRUE;
  67 }
  68
  69 static void parse_value_free(ObtDDParseValue *v)
  70 {
  71     switch (v->type) {
  72     case OBT_DDPARSE_STRING:
  73     case OBT_DDPARSE_LOCALESTRING:
  74         g_free(v->value.string); break;
  75     case OBT_DDPARSE_STRINGS:
  76     case OBT_DDPARSE_LOCALESTRINGS:
  77         g_free(v->value.strings.s);
  78         v->value.strings.n = 0;
  79         break;
  80     case OBT_DDPARSE_BOOLEAN:
  81     case OBT_DDPARSE_NUMERIC:
  82     case OBT_DDPARSE_ENUM_APPLICATION:
  83         break;
  84     default:
  85         g_assert_not_reached();
  86     }
  87     g_slice_free(ObtDDParseValue, v);
  88 }
  89
  90 static ObtDDParseGroup* parse_group_new(gchar *name, ObtDDParseValueFunc f)
  91 {
  92     ObtDDParseGroup *g = g_slice_new(ObtDDParseGroup);
  93     g->name = name;
  94     g->value_func = f;
  95     g->seen = FALSE;
  96     g->key_hash = g_hash_table_new_full(g_str_hash, g_str_equal,
  97                                         g_free,
  98                                         (GDestroyNotify)parse_value_free);
  99     return g;
 100 }
 101
 102 static void parse_group_free(ObtDDParseGroup *g)
 103 {
 104     g_free(g->name);
 105     g_hash_table_destroy(g->key_hash);
 106     g_slice_free(ObtDDParseGroup, g);
 107 }
 108
 109 /*! Reads an input string, strips out invalid stuff, and parses
 110     backslash-stuff.
 111     If @nstrings is not NULL, then it splits the output string at ';'
 112     characters.  They are all returned in the same string with null zeros
 113     between them, @nstrings is set to the number of such strings.
 114  */
 115 static gchar* parse_value_string(const gchar *in,
 116                                  gboolean locale,
 117                                  gulong *nstrings,
 118                                  const ObtDDParse *const parse,
 119                                  gboolean *error)
 120 {
 121     const gint bytes = strlen(in);
 122     gboolean backslash;
 123     gchar *out, *o;
 124     const gchar *end, *i;
 125
 126     g_return_val_if_fail(in != NULL, NULL);
 127
 128     if (!locale) {
 129         end = in + bytes;
 130         for (i = in; i < end; ++i) {
 131             if ((guchar)*i >= 127 || (guchar)*i < 32) {
 132                 /* non-control character ascii */
 133                 end = i;
 134                 parse_error("Invalid bytes in string", parse, error);
 135                 break;
 136             }
 137         }
 138     }
 139     else if (!g_utf8_validate(in, bytes, &end))
 140         parse_error("Invalid bytes in localestring", parse, error);
 141
 142     if (nstrings) *nstrings = 1;
 143
 144     out = g_new(char, bytes + 1);
 145     i = in; o = out;
 146     backslash = FALSE;
 147     while (i < end) {
 148         const gchar *next = locale ? g_utf8_find_next_char(i, end) : i+1;
 149         if (backslash) {
 150             switch(*i) {
 151             case 's': *o++ = ' '; break;
 152             case 'n': *o++ = '\n'; break;
 153             case 't': *o++ = '\t'; break;
 154             case 'r': *o++ = '\r'; break;
 155             case ';': *o++ = ';'; break;
 156             case '\\': *o++ = '\\'; break;
 157             default:
 158                 parse_error((locale ?
 159                              "Invalid escape sequence in localestring" :
 160                              "Invalid escape sequence in string"),
 161                             parse, error);
 162             }
 163             backslash = FALSE;
 164         }
 165         else if (*i == '\\')
 166             backslash = TRUE;
 167         else if (*i == ';' && nstrings) {
 168             ++nstrings;
 169             *o = '\0';
 170         }
 171         else if ((guchar)*i == 127 || (guchar)*i < 32) {
 172             /* avoid ascii control characters */
 173             parse_error("Found control character in string", parse, error);
 174             break;
 175         }
 176         else {
 177             memcpy(o, i, next-i);
 178             o += next-i;
 179         }
 180         i = next;
 181     }
 182     *o = '\0';
 183     return o;
 184 }
 185
 186 static gboolean parse_value_boolean(const gchar *in,
 187                                     const ObtDDParse *const parse,
 188                                     gboolean *error)
 189 {
 190     if (strcmp(in, "true") == 0)
 191         return TRUE;
 192     else if (strcmp(in, "false") != 0)
 193         parse_error("Invalid boolean value", parse, error);
 194     return FALSE;
 195 }
 196
 197 static gfloat parse_value_numeric(const gchar *in,
 198                                   const ObtDDParse *const parse,
 199                                   gboolean *error)
 200 {
 201     gfloat out = 0;
 202     if (sscanf(in, "%f", &out) == 0)
 203         parse_error("Invalid numeric value", parse, error);
 204     return out;
 205 }
 206
 207 static gboolean parse_file_line(FILE *f, gchar **buf,
 208                                 gulong *size, gulong *read,
 209                                 ObtDDParse *parse, gboolean *error)
 210 {
 211     const gulong BUFMUL = 80;
 212     size_t ret;
 213     gulong i, null;
 214
 215     if (*size == 0) {
 216         g_assert(*read == 0);
 217         *size = BUFMUL;
 218         *buf = g_new(char, *size);
 219     }
 220
 221     /* remove everything up to a null zero already in the buffer and shift
 222        the rest to the front */
 223     null = *size;
 224     for (i = 0; i < *read; ++i) {
 225         if (null < *size)
 226             (*buf)[i-null-1] = (*buf)[i];
 227         else if ((*buf)[i] == '\0')
 228             null = i;
 229     }
 230     if (null < *size)
 231         *read -= null + 1;
 232
 233     /* is there already a newline in the buffer? */
 234     for (i = 0; i < *read; ++i)
 235         if ((*buf)[i] == '\n') {
 236             /* turn it into a null zero and done */
 237             (*buf)[i] = '\0';
 238             return TRUE;
 239         }
 240
 241     /* we need to read some more to find a newline */
 242     while (TRUE) {
 243         gulong eol;
 244         gchar *newread;
 245
 246         newread = *buf + *read;
 247         ret = fread(newread, sizeof(char), *size-*read, f);
 248         if (ret < *size - *read && !feof(f)) {
 249             parse_error("Error reading", parse, error);
 250             return FALSE;
 251         }
 252         *read += ret;
 253
 254         /* strip out null zeros in the input and look for an endofline */
 255         null = 0;
 256         eol = *size;
 257         for (i = newread-*buf; i < *read; ++i) {
 258             if (null > 0)
 259                 (*buf)[i] = (*buf)[i+null];
 260             if ((*buf)[i] == '\0') {
 261                 ++null;
 262                 --(*read);
 263                 --i; /* try again */
 264             }
 265             else if ((*buf)[i] == '\n' && eol == *size) {
 266                 eol = i;
 267                 /* turn it into a null zero */
 268                 (*buf)[i] = '\0';
 269             }
 270         }
 271
 272         if (eol != *size)
 273             /* found an endofline, done */
 274             break;
 275         else if (feof(f) && *read < *size) {
 276             /* found the endoffile, done (if there is space) */
 277             if (*read > 0) {
 278                 /* stick a null zero on if there is test on the last line */
 279                 (*buf)[(*read)++] = '\0';
 280             }
 281             break;
 282         }
 283         else {
 284             /* read more */
 285             size += BUFMUL;
 286             *buf = g_renew(char, *buf, *size);
 287         }
 288     }
 289     return *read > 0;
 290 }
 291
 292 static void parse_group(const gchar *buf, gulong len,
 293                         ObtDDParse *parse, gboolean *error)
 294 {
 295     ObtDDParseGroup *g;
 296     gchar *group;
 297     gulong i;
 298
 299     /* get the group name */
 300     group = g_strndup(buf+1, len-2);
 301     for (i = 0; i < len-2; ++i)
 302         if ((guchar)group[i] < 32 || (guchar)group[i] >= 127) {
 303             /* valid ASCII only */
 304             parse_error("Invalid character found", parse, NULL);
 305             group[i] = '\0'; /* stopping before this character */
 306             break;
 307         }
 308
 309     /* make sure it's a new group */
 310     g = g_hash_table_lookup(parse->group_hash, group);
 311     if (g && g->seen) {
 312         parse_error("Duplicate group found", parse, error);
 313         g_free(group);
 314         return;
 315     }
 316     /* if it's the first group, make sure it's named Desktop Entry */
 317     else if (!parse->group && strcmp(group, "Desktop Entry") != 0)
 318     {
 319         parse_error("Incorrect group found, "
 320                     "expected [Desktop Entry]",
 321                     parse, error);
 322         g_free(group);
 323         return;
 324     }
 325     else {
 326         if (!g) {
 327             g = parse_group_new(group, NULL);
 328             g_hash_table_insert(parse->group_hash, g->name, g);
 329         }
 330         else
 331             g_free(group);
 332
 333         g->seen = TRUE;
 334         parse->group = g;
 335         g_print("Found group %s\n", g->name);
 336     }
 337 }
 338
 339 static void parse_key_value(const gchar *buf, gulong len,
 340                             ObtDDParse *parse, gboolean *error)
 341 {
 342     gulong i, keyend, valstart, eq;
 343     char *key;
 344
 345     /* find the end of the key */
 346     for (i = 0; i < len; ++i)
 347         if (!(((guchar)buf[i] >= 'A' && (guchar)buf[i] <= 'Z') ||
 348               ((guchar)buf[i] >= 'a' && (guchar)buf[i] <= 'z') ||
 349               ((guchar)buf[i] >= '0' && (guchar)buf[i] <= '9') ||
 350               ((guchar)buf[i] == '-'))) {
 351             /* not part of the key */
 352             keyend = i;
 353             break;
 354         }
 355     if (keyend < 1) {
 356         parse_error("Empty key", parse, error);
 357         return;
 358     }
 359     /* find the = character */
 360     for (i = keyend; i < len; ++i) {
 361         if (buf[i] == '=') {
 362             eq = i;
 363             break;
 364         }
 365         else if (buf[i] != ' ') {
 366             parse_error("Invalid character in key name", parse, error);
 367             return ;
 368         }
 369     }
 370     if (i == len) {
 371         parse_error("Key without value found", parse, error);
 372         return;
 373     }
 374     /* find the start of the value */
 375     for (i = eq+1; i < len; ++i)
 376         if (buf[i] != ' ') {
 377             valstart = i;
 378             break;
 379         }
 380     if (i == len) {
 381         parse_error("Empty value found", parse, error);
 382         return;
 383     }
 384
 385     key = g_strndup(buf, keyend);
 386     if (g_hash_table_lookup(parse->group->key_hash, key)) {
 387         parse_error("Duplicate key found", parse, error);
 388         g_free(key);
 389         return;
 390     }
 391     g_print("Found key/value %s=%s.\n", key, buf+valstart);
 392     if (parse->group->value_func)
 393         if (!parse->group->value_func(key, buf+valstart, parse, error)) {
 394             parse_error("Unknown key", parse, error);
 395             g_free(key);
 396         }
 397 }
 398
 399 static gboolean parse_file(FILE *f, ObtDDParse *parse)
 400 {
 401     gchar *buf = NULL;
 402     gulong bytes = 0, read = 0;
 403     gboolean error = FALSE;
 404
 405     while (!error && parse_file_line(f, &buf, &bytes, &read, parse, &error)) {
 406         gulong len = strlen(buf);
 407         if (buf[0] == '#' || buf[0] == '\0')
 408             ; /* ignore comment lines */
 409         else if (buf[0] == '[' && buf[len-1] == ']')
 410             parse_group(buf, len, parse, &error);
 411         else if (!parse->group)
 412             /* just ignore keys outside of groups */
 413             parse_error("Key found before group", parse, NULL);
 414         else
 415             /* ignore errors in key-value pairs and continue */
 416             parse_key_value(buf, len, parse, NULL);
 417         ++parse->lineno;
 418     }
 419
 420     if (buf) g_free(buf);
 421     return !error;
 422 }
 423
 424 static gboolean parse_desktop_entry_value(gchar *key, const gchar *val,
 425                                           ObtDDParse *parse, gboolean *error)
 426 {
 427     ObtDDParseValue v, *pv;
 428
 429     switch (key[0]) {
 430     case 'C':
 431         switch (key[1]) {
 432         case 'a': /* Categories */
 433             if (strcmp(key+2, "tegories")) return FALSE;
 434             v.type = OBT_DDPARSE_STRINGS; break;
 435         case 'o': /* Comment */
 436             if (strcmp(key+2, "mment")) return FALSE;
 437             v.type = OBT_DDPARSE_LOCALESTRING; break;
 438         default:
 439             return FALSE;
 440         }
 441         break;
 442     case 'E': /* Exec */
 443         if (strcmp(key+1, "xec")) return FALSE;
 444         v.type = OBT_DDPARSE_STRING; break;
 445     case 'G': /* GenericName */
 446         if (strcmp(key+1, "enericName")) return FALSE;
 447         v.type = OBT_DDPARSE_LOCALESTRING; break;
 448     case 'I': /* Icon */
 449         if (strcmp(key+1, "con")) return FALSE;
 450         v.type = OBT_DDPARSE_LOCALESTRING; break;
 451     case 'H': /* Hidden */
 452         if (strcmp(key+1, "idden")) return FALSE;
 453         v.type = OBT_DDPARSE_BOOLEAN; break;
 454     case 'M': /* MimeType */
 455         if (strcmp(key+1, "imeType")) return FALSE;
 456         v.type = OBT_DDPARSE_STRINGS; break;
 457     case 'N':
 458         switch (key[1]) {
 459         case 'a': /* Name */
 460             if (strcmp(key+2, "me")) return FALSE;
 461             v.type = OBT_DDPARSE_LOCALESTRING; break;
 462         case 'o':
 463             switch (key[2]) {
 464             case 'D': /* NoDisplay */
 465                 if (strcmp(key+3, "isplay")) return FALSE;
 466                 v.type = OBT_DDPARSE_BOOLEAN; break;
 467             case 't': /* NotShowIn */
 468                 if (strcmp(key+3, "ShowIn")) return FALSE;
 469                 v.type = OBT_DDPARSE_STRINGS; break;
 470             default:
 471                 return FALSE;
 472             }
 473             break;
 474         default:
 475             return FALSE;
 476         }
 477         break;
 478     case 'P': /* Path */
 479         if (strcmp(key+1, "ath")) return FALSE;
 480         v.type = OBT_DDPARSE_STRING; break;
 481     case 'S': /* Path */
 482         if (key[1] == 't' && key[2] == 'a' && key[3] == 'r' &&
 483             key[4] == 't' && key[5] == 'u' && key[6] == 'p')
 484             switch (key[7]) {
 485             case 'N': /* StartupNotify */
 486                 if (strcmp(key+8, "otify")) return FALSE;
 487                 v.type = OBT_DDPARSE_BOOLEAN; break;
 488             case 'W': /* StartupWMClass */
 489                 if (strcmp(key+8, "MClass")) return FALSE;
 490                 v.type = OBT_DDPARSE_STRING; break;
 491             default:
 492                 return FALSE;
 493             }
 494         else
 495             return FALSE;
 496         break;
 497     case 'T':
 498         switch (key[1]) {
 499         case 'e': /* Terminal */
 500             if (strcmp(key+2, "rminal")) return FALSE;
 501             v.type = OBT_DDPARSE_BOOLEAN; break;
 502         case 'r': /* TryExec */
 503             if (strcmp(key+2, "yExec")) return FALSE;
 504             v.type = OBT_DDPARSE_STRING; break;
 505         case 'y': /* Type */
 506             if (strcmp(key+2, "pe")) return FALSE;
 507             v.type = OBT_DDPARSE_STRING; break;
 508         default:
 509             return FALSE;
 510         }
 511         break;
 512     case 'U': /* URL */
 513         if (strcmp(key+1, "RL")) return FALSE;
 514         v.type = OBT_DDPARSE_STRING; break;
 515     case 'V': /* MimeType */
 516         if (strcmp(key+1, "ersion")) return FALSE;
 517         v.type = OBT_DDPARSE_STRING; break;
 518     default:
 519         return FALSE;
 520     }
 521
 522     /* parse the value */
 523     switch (v.type) {
 524     case OBT_DDPARSE_STRING:
 525         v.value.string = parse_value_string(val, FALSE, NULL, parse, error);
 526         g_assert(v.value.string);
 527         break;
 528     case OBT_DDPARSE_LOCALESTRING:
 529         v.value.string = parse_value_string(val, TRUE, NULL, parse, error);
 530         g_assert(v.value.string);
 531         break;
 532     case OBT_DDPARSE_STRINGS:
 533         v.value.strings.s = parse_value_string(val, FALSE, &v.value.strings.n,
 534                                                parse, error);
 535         g_assert(v.value.strings.s);
 536         g_assert(v.value.strings.n);
 537         break;
 538     case OBT_DDPARSE_LOCALESTRINGS:
 539         v.value.strings.s = parse_value_string(val, TRUE, &v.value.strings.n,
 540                                                parse, error);
 541         g_assert(v.value.strings.s);
 542         g_assert(v.value.strings.n);
 543         break;
 544     case OBT_DDPARSE_BOOLEAN:
 545         v.value.boolean = parse_value_boolean(val, parse, error);
 546         break;
 547     case OBT_DDPARSE_NUMERIC:
 548         v.value.numeric = parse_value_numeric(val, parse, error);
 549         break;
 550     case OBT_DDPARSE_ENUM_APPLICATION:
 551         if (val[0] == 'A' && strcmp(val+1, "pplication") == 0)
 552             v.value.enumerable = OBT_LINK_TYPE_APPLICATION;
 553         else if (val[0] == 'L' && strcmp(val+1, "ink") == 0)
 554             v.value.enumerable = OBT_LINK_TYPE_URL;
 555         else if (val[0] == 'D' && strcmp(val+1, "irectory") == 0)
 556             v.value.enumerable = OBT_LINK_TYPE_DIRECTORY;
 557         else {
 558             parse_error("Unknown Type", parse, error);
 559             return FALSE;
 560         }
 561         break;
 562     default:
 563         g_assert_not_reached();
 564     }
 565
 566     pv = g_slice_new(ObtDDParseValue);
 567     *pv = v;
 568     g_hash_table_insert(parse->group->key_hash, key, pv);
 569     return TRUE;
 570 }
 571
 572 GHashTable* obt_ddparse_file(const gchar *name, GSList *paths)
 573 {
 574     ObtDDParse parse;
 575     ObtDDParseGroup *desktop_entry;
 576     GSList *it;
 577     FILE *f;
 578     gboolean success;
 579
 580     parse.filename = NULL;
 581     parse.lineno = 0;
 582     parse.group = NULL;
 583     parse.group_hash = g_hash_table_new_full(g_str_hash,
 584                                              g_str_equal,
 585                                              NULL,
 586                                              (GDestroyNotify)parse_group_free);
 587
 588     /* set up the groups (there's only one right now) */
 589     desktop_entry = parse_group_new(g_strdup("Desktop Entry"),
 590                                     parse_desktop_entry_value);
 591     g_hash_table_insert(parse.group_hash, desktop_entry->name, desktop_entry);
 592
 593     success = FALSE;
 594     for (it = paths; it && !success; it = g_slist_next(it)) {
 595         gchar *path = g_strdup_printf("%s/%s", (char*)it->data, name);
 596         if ((f = fopen(path, "r"))) {
 597             parse.filename = path;
 598             parse.lineno = 1;
 599             success = parse_file(f, &parse);
 600             fclose(f);
 601         }
 602         g_free(path);
 603     }
 604     if (!success) {
 605         g_hash_table_destroy(parse.group_hash);
 606         return NULL;
 607     }
 608     else
 609         return parse.group_hash;
 610 }
 611
 612 GHashTable* obt_ddparse_group_keys(ObtDDParseGroup *g)
 613 {
 614     return g->key_hash;
 615 }