src/config/file.c

   1 /*****************************************************************************
   2  * file.c: configuration file handling
   3  *****************************************************************************
   4  * Copyright (C) 2001-2007 VLC authors and VideoLAN
   5  * $Id$
   6  *
   7  * Authors: Gildas Bazin <gbazin@videolan.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17  * GNU Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 #ifdef HAVE_CONFIG_H
  25 # include "config.h"
  26 #endif
  27
  28 #include <errno.h>                                                  /* errno */
  29 #include <assert.h>
  30 #include <limits.h>
  31 #include <fcntl.h>
  32 #include <sys/stat.h>
  33 #ifdef __APPLE__
  34 #   include <xlocale.h>
  35 #elif defined(HAVE_USELOCALE)
  36 #include <locale.h>
  37 #endif
  38 #include <unistd.h>
  39
  40 #include <vlc_common.h>
  41 #include "../libvlc.h"
  42 #include <vlc_charset.h>
  43 #include <vlc_fs.h>
  44 #include <vlc_keys.h>
  45 #include <vlc_modules.h>
  46 #include <vlc_plugin.h>
  47
  48 #include "configuration.h"
  49 #include "modules/modules.h"
  50
  51 static inline char *strdupnull (const char *src)
  52 {
  53     return src ? strdup (src) : NULL;
  54 }
  55
  56 /**
  57  * Get the user's configuration file
  58  */
  59 static char *config_GetConfigFile( vlc_object_t *obj )
  60 {
  61     char *psz_file = var_CreateGetNonEmptyString( obj, "config" );
  62     var_Destroy( obj, "config" );
  63     if( psz_file == NULL )
  64     {
  65         char *psz_dir = config_GetUserDir( VLC_CONFIG_DIR );
  66
  67         if( asprintf( &psz_file, "%s" DIR_SEP CONFIG_FILE, psz_dir ) == -1 )
  68             psz_file = NULL;
  69         free( psz_dir );
  70     }
  71     return psz_file;
  72 }
  73
  74 static FILE *config_OpenConfigFile( vlc_object_t *p_obj )
  75 {
  76     char *psz_filename = config_GetConfigFile( p_obj );
  77     if( psz_filename == NULL )
  78         return NULL;
  79
  80     msg_Dbg( p_obj, "opening config file (%s)", psz_filename );
  81
  82     FILE *p_stream = vlc_fopen( psz_filename, "rt" );
  83     if( p_stream == NULL && errno != ENOENT )
  84     {
  85         msg_Err( p_obj, "cannot open config file (%s): %s",
  86                  psz_filename, vlc_strerror_c(errno) );
  87
  88     }
  89 #if !( defined(_WIN32) || defined(__APPLE__) || defined(__OS2__) )
  90     else if( p_stream == NULL && errno == ENOENT )
  91     {
  92         /* This is the fallback for pre XDG Base Directory
  93          * Specification configs */
  94         char *home = config_GetUserDir(VLC_HOME_DIR);
  95         char *psz_old;
  96
  97         if( home != NULL
  98          && asprintf( &psz_old, "%s/.vlc/" CONFIG_FILE,
  99                       home ) != -1 )
 100         {
 101             p_stream = vlc_fopen( psz_old, "rt" );
 102             if( p_stream )
 103             {
 104                 /* Old config file found. We want to write it at the
 105                  * new location now. */
 106                 msg_Info( p_obj->p_libvlc, "Found old config file at %s. "
 107                           "VLC will now use %s.", psz_old, psz_filename );
 108                 char *psz_readme;
 109                 if( asprintf(&psz_readme,"%s/.vlc/README",
 110                              home ) != -1 )
 111                 {
 112                     FILE *p_readme = vlc_fopen( psz_readme, "wt" );
 113                     if( p_readme )
 114                     {
 115                         fprintf( p_readme, "The VLC media player "
 116                                  "configuration folder has moved to comply\n"
 117                                  "with the XDG Base Directory Specification "
 118                                  "version 0.6. Your\nconfiguration has been "
 119                                  "copied to the new location:\n%s\nYou can "
 120                                  "delete this directory and all its contents.",
 121                                   psz_filename);
 122                         fclose( p_readme );
 123                     }
 124                     free( psz_readme );
 125                 }
 126                 /* Remove the old configuration file so that --reset-config
 127                  * can work properly. Fortunately, Linux allows removing
 128                  * open files - with most filesystems. */
 129                 unlink( psz_old );
 130             }
 131             free( psz_old );
 132         }
 133         free( home );
 134     }
 135 #endif
 136     free( psz_filename );
 137     return p_stream;
 138 }
 139
 140
 141 static int64_t strtoi (const char *str)
 142 {
 143     char *end;
 144     long long l;
 145
 146     errno = 0;
 147     l = strtoll (str, &end, 0);
 148
 149     if (!errno)
 150     {
 151 #if (LLONG_MAX > 0x7fffffffffffffffLL)
 152         if (l > 0x7fffffffffffffffLL
 153          || l < -0x8000000000000000LL)
 154             errno = ERANGE;
 155 #endif
 156         if (*end)
 157             errno = EINVAL;
 158     }
 159     return l;
 160 }
 161
 162 #undef config_LoadConfigFile
 163 /*****************************************************************************
 164  * config_LoadConfigFile: loads the configuration file.
 165  *****************************************************************************
 166  * This function is called to load the config options stored in the config
 167  * file.
 168  *****************************************************************************/
 169 int config_LoadConfigFile( vlc_object_t *p_this )
 170 {
 171     FILE *file;
 172
 173     file = config_OpenConfigFile (p_this);
 174     if (file == NULL)
 175         return VLC_EGENERIC;
 176
 177     /* Look for UTF-8 Byte Order Mark */
 178     char * (*convert) (const char *) = strdupnull;
 179     char bom[3];
 180
 181     if ((fread (bom, 1, 3, file) != 3)
 182      || memcmp (bom, "\xEF\xBB\xBF", 3))
 183     {
 184         convert = FromLocaleDup;
 185         rewind (file); /* no BOM, rewind */
 186     }
 187
 188     char *line = NULL;
 189     size_t bufsize;
 190     ssize_t linelen;
 191
 192     /* Ensure consistent number formatting... */
 193     locale_t loc = newlocale (LC_NUMERIC_MASK, "C", NULL);
 194     locale_t baseloc = uselocale (loc);
 195
 196     vlc_rwlock_wrlock (&config_lock);
 197     while ((linelen = getline (&line, &bufsize, file)) != -1)
 198     {
 199         line[linelen - 1] = '\0'; /* trim newline */
 200
 201         /* Ignore comments, section and empty lines */
 202         if (memchr ("#[", line[0], 3) != NULL)
 203             continue;
 204
 205         /* look for option name */
 206         const char *psz_option_name = line;
 207
 208         char *ptr = strchr (line, '=');
 209         if (ptr == NULL)
 210             continue; /* syntax error */
 211         *ptr = '\0';
 212
 213         module_config_t *item = config_FindConfig (p_this, psz_option_name);
 214         if (item == NULL)
 215             continue;
 216
 217         const char *psz_option_value = ptr + 1;
 218         switch (CONFIG_CLASS(item->i_type))
 219         {
 220             case CONFIG_ITEM_BOOL:
 221             case CONFIG_ITEM_INTEGER:
 222             {
 223                 int64_t l;
 224
 225                 errno = 0;
 226                 l = strtoi (psz_option_value);
 227                 if ((l > item->max.i) || (l < item->min.i))
 228                     errno = ERANGE;
 229                 if (errno)
 230                     msg_Warn (p_this, "Integer value (%s) for %s: %s",
 231                               psz_option_value, psz_option_name,
 232                               vlc_strerror_c(errno));
 233                 else
 234                     item->value.i = l;
 235                 break;
 236             }
 237
 238             case CONFIG_ITEM_FLOAT:
 239                 if (!*psz_option_value)
 240                     break;                    /* ignore empty option */
 241                 item->value.f = (float)atof (psz_option_value);
 242                 break;
 243
 244             default:
 245                 free ((char *)item->value.psz);
 246                 item->value.psz = convert (psz_option_value);
 247                 break;
 248         }
 249     }
 250     vlc_rwlock_unlock (&config_lock);
 251     free (line);
 252
 253     if (ferror (file))
 254     {
 255         msg_Err (p_this, "error reading configuration: %s",
 256                  vlc_strerror_c(errno));
 257         clearerr (file);
 258     }
 259     fclose (file);
 260
 261     if (loc != (locale_t)0)
 262     {
 263         uselocale (baseloc);
 264         freelocale (loc);
 265     }
 266     return 0;
 267 }
 268
 269 /*****************************************************************************
 270  * config_CreateDir: Create configuration directory if it doesn't exist.
 271  *****************************************************************************/
 272 int config_CreateDir( vlc_object_t *p_this, const char *psz_dirname )
 273 {
 274     if( !psz_dirname || !*psz_dirname ) return -1;
 275
 276     if( vlc_mkdir( psz_dirname, 0700 ) == 0 )
 277         return 0;
 278
 279     switch( errno )
 280     {
 281         case EEXIST:
 282             return 0;
 283
 284         case ENOENT:
 285         {
 286             /* Let's try to create the parent directory */
 287             char psz_parent[strlen( psz_dirname ) + 1], *psz_end;
 288             strcpy( psz_parent, psz_dirname );
 289
 290             psz_end = strrchr( psz_parent, DIR_SEP_CHAR );
 291             if( psz_end && psz_end != psz_parent )
 292             {
 293                 *psz_end = '\0';
 294                 if( config_CreateDir( p_this, psz_parent ) == 0 )
 295                 {
 296                     if( !vlc_mkdir( psz_dirname, 0700 ) )
 297                         return 0;
 298                 }
 299             }
 300         }
 301     }
 302
 303     msg_Warn( p_this, "could not create %s: %s", psz_dirname,
 304               vlc_strerror_c(errno) );
 305     return -1;
 306 }
 307
 308 static int
 309 config_Write (FILE *file, const char *desc, const char *type,
 310               bool comment, const char *name, const char *fmt, ...)
 311 {
 312     va_list ap;
 313     int ret;
 314
 315     if (desc == NULL)
 316         desc = "?";
 317
 318     if (fprintf (file, "# %s (%s)\n%s%s=", desc, vlc_gettext (type),
 319                  comment ? "#" : "", name) < 0)
 320         return -1;
 321
 322     va_start (ap, fmt);
 323     ret = vfprintf (file, fmt, ap);
 324     va_end (ap);
 325     if (ret < 0)
 326         return -1;
 327
 328     if (fputs ("\n\n", file) == EOF)
 329         return -1;
 330     return 0;
 331 }
 332
 333
 334 static int config_PrepareDir (vlc_object_t *obj)
 335 {
 336     char *psz_configdir = config_GetUserDir (VLC_CONFIG_DIR);
 337     if (psz_configdir == NULL)
 338         return -1;
 339
 340     int ret = config_CreateDir (obj, psz_configdir);
 341     free (psz_configdir);
 342     return ret;
 343 }
 344
 345 #undef config_SaveConfigFile
 346 /**
 347  * Saves the in-memory configuration into a file.
 348  * @return 0 on success, -1 on error.
 349  */
 350 int config_SaveConfigFile (vlc_object_t *p_this)
 351 {
 352
 353     if( config_PrepareDir( p_this ) )
 354     {
 355         msg_Err( p_this, "no configuration directory" );
 356         return -1;
 357     }
 358
 359     /*
 360      * Save module config in file
 361      */
 362     char *temporary;
 363     char *permanent = config_GetConfigFile (p_this);
 364     if (permanent == NULL)
 365         return -1;
 366     if (asprintf (&temporary, "%s.%u", permanent, getpid ()) == -1)
 367     {
 368         free (permanent);
 369         return -1;
 370     }
 371     else
 372     {
 373         struct stat st;
 374
 375         /* Some users make vlcrc read-only to prevent changes.
 376          * The atomic replacement scheme breaks this "feature",
 377          * so we check for read-only by hand. */
 378         if (stat (permanent, &st) == 0 && !(st.st_mode & S_IWUSR))
 379         {
 380             msg_Err (p_this, "configuration file is read-only");
 381             goto error;
 382         }
 383     }
 384
 385     /* Configuration lock must be taken before vlcrc serializer below. */
 386     vlc_rwlock_rdlock (&config_lock);
 387
 388     /* The temporary configuration file is per-PID. Therefore this function
 389      * should be serialized against itself within a given process. */
 390     static vlc_mutex_t lock = VLC_STATIC_MUTEX;
 391     vlc_mutex_lock (&lock);
 392
 393     int fd = vlc_open (temporary, O_CREAT|O_WRONLY|O_TRUNC, S_IRUSR|S_IWUSR);
 394     if (fd == -1)
 395     {
 396         vlc_rwlock_unlock (&config_lock);
 397         vlc_mutex_unlock (&lock);
 398         goto error;
 399     }
 400     FILE *file = fdopen (fd, "wt");
 401     if (file == NULL)
 402     {
 403         msg_Err (p_this, "cannot create configuration file: %s",
 404                  vlc_strerror_c(errno));
 405         vlc_rwlock_unlock (&config_lock);
 406         close (fd);
 407         vlc_mutex_unlock (&lock);
 408         goto error;
 409     }
 410
 411     fprintf( file,
 412         "\xEF\xBB\xBF###\n"
 413         "###  "PACKAGE_NAME" "PACKAGE_VERSION"\n"
 414         "###\n"
 415         "\n"
 416         "###\n"
 417         "### lines beginning with a '#' character are comments\n"
 418         "###\n"
 419         "\n" );
 420
 421     /* Ensure consistent number formatting... */
 422     locale_t loc = newlocale (LC_NUMERIC_MASK, "C", NULL);
 423     locale_t baseloc = uselocale (loc);
 424
 425     /* We would take the config lock here. But this would cause a lock
 426      * inversion with the serializer above and config_AutoSaveConfigFile().
 427     vlc_rwlock_rdlock (&config_lock);*/
 428
 429     /* Look for the selected module, if NULL then save everything */
 430     size_t count;
 431     module_t **list = module_list_get (&count);
 432     for (size_t i = 0; i < count; i++)
 433     {
 434         module_t *p_parser = list[i];
 435         module_config_t *p_item, *p_end;
 436
 437         if( !p_parser->i_config_items )
 438             continue;
 439
 440         fprintf( file, "[%s]", module_get_object (p_parser) );
 441         if( p_parser->psz_longname )
 442             fprintf( file, " # %s\n\n", p_parser->psz_longname );
 443         else
 444             fprintf( file, "\n\n" );
 445
 446         for( p_item = p_parser->p_config, p_end = p_item + p_parser->confsize;
 447              p_item < p_end;
 448              p_item++ )
 449         {
 450             if (!CONFIG_ITEM(p_item->i_type)   /* ignore hint */
 451              || p_item->b_removed              /* ignore deprecated option */
 452              || p_item->b_unsaveable)          /* ignore volatile option */
 453                 continue;
 454
 455             if (IsConfigIntegerType (p_item->i_type))
 456             {
 457                 int64_t val = p_item->value.i;
 458                 config_Write (file, p_item->psz_text,
 459                              (CONFIG_CLASS(p_item->i_type) == CONFIG_ITEM_BOOL)
 460                                   ? N_("boolean") : N_("integer"),
 461                               val == p_item->orig.i,
 462                               p_item->psz_name, "%"PRId64, val);
 463             }
 464             else
 465             if (IsConfigFloatType (p_item->i_type))
 466             {
 467                 float val = p_item->value.f;
 468                 config_Write (file, p_item->psz_text, N_("float"),
 469                               val == p_item->orig.f,
 470                               p_item->psz_name, "%f", val);
 471             }
 472             else
 473             {
 474                 const char *psz_value = p_item->value.psz;
 475                 bool modified;
 476
 477                 assert (IsConfigStringType (p_item->i_type));
 478
 479                 modified = !!strcmp (psz_value ? psz_value : "",
 480                                      p_item->orig.psz ? p_item->orig.psz : "");
 481                 config_Write (file, p_item->psz_text, N_("string"),
 482                               !modified, p_item->psz_name, "%s",
 483                               psz_value ? psz_value : "");
 484             }
 485         }
 486     }
 487     vlc_rwlock_unlock (&config_lock);
 488
 489     module_list_free (list);
 490     if (loc != (locale_t)0)
 491     {
 492         uselocale (baseloc);
 493         freelocale (loc);
 494     }
 495
 496     /*
 497      * Flush to disk and replace atomically
 498      */
 499     fflush (file); /* Flush from run-time */
 500     if (ferror (file))
 501     {
 502         vlc_unlink (temporary);
 503         vlc_mutex_unlock (&lock);
 504         msg_Err (p_this, "cannot write configuration file");
 505         fclose (file);
 506         goto error;
 507     }
 508 #if defined(__APPLE__) || defined(__ANDROID__)
 509     fsync (fd); /* Flush from OS */
 510 #else
 511     fdatasync (fd); /* Flush from OS */
 512 #endif
 513 #if defined (_WIN32) || defined (__OS2__)
 514     /* Windows cannot (re)move open files nor overwrite existing ones */
 515     fclose (file);
 516     vlc_unlink (permanent);
 517 #endif
 518     /* Atomically replace the file... */
 519     if (vlc_rename (temporary, permanent))
 520         vlc_unlink (temporary);
 521     /* (...then synchronize the directory, err, TODO...) */
 522     /* ...and finally close the file */
 523     vlc_mutex_unlock (&lock);
 524 #if !defined (_WIN32) && !defined (__OS2__)
 525     fclose (file);
 526 #endif
 527
 528     free (temporary);
 529     free (permanent);
 530     return 0;
 531
 532 error:
 533     free (temporary);
 534     free (permanent);
 535     return -1;
 536 }
 537
 538 int config_AutoSaveConfigFile( vlc_object_t *p_this )
 539 {
 540     int ret = 0;
 541
 542     assert( p_this );
 543
 544     vlc_rwlock_rdlock (&config_lock);
 545     if (config_dirty)
 546     {
 547         /* Note: this will get the read lock recursively. Ok. */
 548         ret = config_SaveConfigFile (p_this);
 549         config_dirty = (ret != 0);
 550     }
 551     vlc_rwlock_unlock (&config_lock);
 552
 553     return ret;
 554 }