src/config/chain.c

   1 /*****************************************************************************
   2  * chain.c : configuration module chain parsing stuff
   3  *****************************************************************************
   4  * Copyright (C) 2002-2007 VLC authors and VideoLAN
   5  * $Id$
   6  *
   7  * Authors: Christophe Massiot <massiot@via.ecp.fr>
   8  *          Laurent Aimar <fenrir@via.ecp.fr>
   9  *          Eric Petit <titer@videolan.org>
  10  *
  11  * This program is free software; you can redistribute it and/or modify it
  12  * under the terms of the GNU Lesser General Public License as published by
  13  * the Free Software Foundation; either version 2.1 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  19  * GNU Lesser General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public License
  22  * along with this program; if not, write to the Free Software Foundation,
  23  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  24  *****************************************************************************/
  25
  26 /*****************************************************************************
  27  * Preamble
  28  *****************************************************************************/
  29
  30 #ifdef HAVE_CONFIG_H
  31 # include "config.h"
  32 #endif
  33
  34 #include <vlc_common.h>
  35 #include "libvlc.h"
  36 #include <vlc_charset.h>
  37
  38 #include "vlc_interface.h"
  39
  40 /*****************************************************************************
  41  * Local prototypes
  42  *****************************************************************************/
  43 static bool IsEscapeNeeded( char c )
  44 {
  45     return c == '\'' || c == '"' || c == '\\';
  46 }
  47 static bool IsEscape( const char *psz )
  48 {
  49     if( !psz )
  50         return false;
  51     return psz[0] == '\\' && IsEscapeNeeded( psz[1] );
  52 }
  53 static bool IsSpace( char c  )
  54 {
  55     return c == ' ' || c == '\t';
  56 }
  57
  58 #define SKIPSPACE( p ) p += strspn( p, " \t" )
  59 #define SKIPTRAILINGSPACE( p, e ) \
  60     do { while( e > p && IsSpace( *(e-1) ) ) e--; } while(0)
  61
  62 /**
  63  * This function will return a pointer after the end of a string element.
  64  * It will search the closing element which is
  65  * } for { (it will handle nested { ... })
  66  * " for "
  67  * ' for '
  68  */
  69 static const char *ChainGetEnd( const char *psz_string )
  70 {
  71     const char *p = psz_string;
  72     char c;
  73
  74     if( !psz_string )
  75         return NULL;
  76
  77     /* Look for a opening character */
  78     SKIPSPACE( p );
  79
  80     for( ;; p++)
  81     {
  82         if( *p == '\0' || *p == ',' || *p == '}' )
  83             return p;
  84
  85         if( *p == '{' || *p == '"' || *p == '\'' )
  86             break;
  87     }
  88
  89     /* Set c to the closing character */
  90     if( *p == '{' )
  91         c = '}';
  92     else
  93         c = *p;
  94     p++;
  95
  96     /* Search the closing character, handle nested {..} */
  97     for( ;; )
  98     {
  99         if( *p == '\0')
 100             return p;
 101
 102         if( IsEscape( p ) )
 103             p += 2;
 104         else if( *p == c )
 105             return ++p;
 106         else if( *p == '{' && c == '}' )
 107             p = ChainGetEnd( p );
 108         else
 109             p++;
 110     }
 111 }
 112
 113 /**
 114  * It will extract an option value (=... or {...}).
 115  * It will remove the initial = if present but keep the {}
 116  */
 117 static char *ChainGetValue( const char **ppsz_string )
 118 {
 119     const char *p = *ppsz_string;
 120
 121     char *psz_value = NULL;
 122     const char *end;
 123     bool b_keep_brackets = (*p == '{');
 124
 125     if( *p == '=' )
 126         p++;
 127
 128     end = ChainGetEnd( p );
 129     if( end <= p )
 130     {
 131         psz_value = NULL;
 132     }
 133     else
 134     {
 135         /* Skip heading and trailing spaces.
 136          * This ain't necessary but will avoid simple
 137          * user mistakes. */
 138         SKIPSPACE( p );
 139     }
 140
 141     if( end <= p )
 142     {
 143         psz_value = NULL;
 144     }
 145     else
 146     {
 147         if( *p == '\'' || *p == '"' || ( !b_keep_brackets && *p == '{' ) )
 148         {
 149             p++;
 150
 151             if( *(end-1) != '\'' && *(end-1) == '"' )
 152                 SKIPTRAILINGSPACE( p, end );
 153
 154             if( end - 1 <= p )
 155                 psz_value = NULL;
 156             else
 157                 psz_value = strndup( p, end -1 - p );
 158         }
 159         else
 160         {
 161             SKIPTRAILINGSPACE( p, end );
 162             if( end <= p )
 163                 psz_value = NULL;
 164             else
 165                 psz_value = strndup( p, end - p );
 166         }
 167     }
 168
 169     /* */
 170     if( psz_value )
 171         config_StringUnescape( psz_value );
 172
 173     /* */
 174     *ppsz_string = end;
 175     return psz_value;
 176 }
 177
 178 /* Parse all name=value[,] elements */
 179 const char *config_ChainParseOptions( config_chain_t **pp_cfg, const char *psz_opts )
 180 {
 181     config_chain_t **pp_next = pp_cfg;
 182     bool first = true;
 183     do
 184     {
 185         if (!first)
 186             psz_opts++; /* skip previous delimiter */
 187         SKIPSPACE( psz_opts );
 188
 189         first = false;
 190
 191         /* Look for the end of the name (,={}_space_) */
 192         size_t len = strcspn( psz_opts, "=,{} \t" );
 193         if( len == 0 )
 194             continue; /* ignore empty parameter */
 195
 196         /* Append the new parameter */
 197         config_chain_t *p_cfg = malloc( sizeof(*p_cfg) );
 198         if( !p_cfg )
 199             break;
 200         p_cfg->psz_name = strndup( psz_opts, len );
 201         psz_opts += len;
 202         p_cfg->psz_value = NULL;
 203         p_cfg->p_next = NULL;
 204
 205         *pp_next = p_cfg;
 206         pp_next = &p_cfg->p_next;
 207
 208         /* Extract the option value */
 209         SKIPSPACE( psz_opts );
 210         if( strchr( "={", *psz_opts ) )
 211         {
 212             p_cfg->psz_value = ChainGetValue( &psz_opts );
 213             SKIPSPACE( psz_opts );
 214         }
 215     }
 216     while( !memchr( "}", *psz_opts, 2 ) );
 217
 218     if( *psz_opts ) psz_opts++; /* skip '}' */;
 219     SKIPSPACE( psz_opts );
 220
 221     return psz_opts;
 222 }
 223
 224 char *config_ChainCreate( char **ppsz_name, config_chain_t **pp_cfg,
 225                           const char *psz_chain )
 226 {
 227     size_t len;
 228
 229     *ppsz_name = NULL;
 230     *pp_cfg    = NULL;
 231
 232     if( !psz_chain )
 233         return NULL;
 234     SKIPSPACE( psz_chain );
 235
 236     /* Look for parameter (a {...} or :...) or end of name (space or nul) */
 237     len = strcspn( psz_chain, "{: \t" );
 238     *ppsz_name = strndup( psz_chain, len );
 239     psz_chain += len;
 240
 241     /* Parse the parameters */
 242     SKIPSPACE( psz_chain );
 243     if( *psz_chain == '{' )
 244         psz_chain = config_ChainParseOptions( pp_cfg, psz_chain );
 245
 246     if( *psz_chain == ':' )
 247         return strdup( psz_chain + 1 );
 248
 249     return NULL;
 250 }
 251
 252 void config_ChainDestroy( config_chain_t *p_cfg )
 253 {
 254     while( p_cfg != NULL )
 255     {
 256         config_chain_t *p_next;
 257
 258         p_next = p_cfg->p_next;
 259
 260         FREENULL( p_cfg->psz_name );
 261         FREENULL( p_cfg->psz_value );
 262         free( p_cfg );
 263
 264         p_cfg = p_next;
 265     }
 266 }
 267
 268 #undef config_ChainParse
 269 void config_ChainParse( vlc_object_t *p_this, const char *psz_prefix,
 270                         const char *const *ppsz_options, config_chain_t *cfg )
 271 {
 272     if( psz_prefix == NULL ) psz_prefix = "";
 273     size_t plen = 1 + strlen( psz_prefix );
 274
 275     /* First, var_Create all variables */
 276     for( size_t i = 0; ppsz_options[i] != NULL; i++ )
 277     {
 278         const char *optname = ppsz_options[i];
 279         if (optname[0] == '*')
 280             optname++;
 281
 282         char name[plen + strlen( optname )];
 283         snprintf( name, sizeof (name), "%s%s", psz_prefix, optname );
 284         if( var_Create( p_this, name,
 285                         config_GetType( p_this, name ) | VLC_VAR_DOINHERIT ) )
 286             return /* VLC_xxx */;
 287     }
 288
 289     /* Now parse options and set value */
 290     for(; cfg; cfg = cfg->p_next )
 291     {
 292         vlc_value_t val;
 293         bool b_yes = true;
 294         bool b_once = false;
 295         module_config_t *p_conf;
 296         int i_type;
 297         size_t i;
 298
 299         if( cfg->psz_name == NULL || *cfg->psz_name == '\0' )
 300             continue;
 301
 302         for( i = 0; ppsz_options[i] != NULL; i++ )
 303         {
 304             if( !strcmp( ppsz_options[i], cfg->psz_name ) )
 305             {
 306                 break;
 307             }
 308             if( ( !strncmp( cfg->psz_name, "no-", 3 ) &&
 309                   !strcmp( ppsz_options[i], cfg->psz_name + 3 ) ) ||
 310                 ( !strncmp( cfg->psz_name, "no", 2 ) &&
 311                   !strcmp( ppsz_options[i], cfg->psz_name + 2 ) ) )
 312             {
 313                 b_yes = false;
 314                 break;
 315             }
 316
 317             if( *ppsz_options[i] == '*' &&
 318                 !strcmp( &ppsz_options[i][1], cfg->psz_name ) )
 319             {
 320                 b_once = true;
 321                 break;
 322             }
 323
 324         }
 325
 326         if( ppsz_options[i] == NULL )
 327         {
 328             msg_Warn( p_this, "option %s is unknown", cfg->psz_name );
 329             continue;
 330         }
 331
 332         /* create name */
 333         char name[plen + strlen( ppsz_options[i] )];
 334         const char *psz_name = name;
 335         snprintf( name, sizeof (name), "%s%s", psz_prefix,
 336                   b_once ? (ppsz_options[i] + 1) : ppsz_options[i] );
 337
 338         /* Check if the option is deprecated */
 339         p_conf = config_FindConfig( p_this, name );
 340
 341         /* This is basically cut and paste from src/misc/configuration.c
 342          * with slight changes */
 343         if( p_conf )
 344         {
 345             if( p_conf->b_removed )
 346             {
 347                 msg_Err( p_this, "Option %s is not supported anymore.",
 348                          name );
 349                 /* TODO: this should return an error and end option parsing
 350                  * ... but doing this would change the VLC API and all the
 351                  * modules so i'll do it later */
 352                 continue;
 353             }
 354         }
 355         /* </Check if the option is deprecated> */
 356
 357         /* get the type of the variable */
 358         i_type = config_GetType( p_this, psz_name );
 359         if( !i_type )
 360         {
 361             msg_Warn( p_this, "unknown option %s (value=%s)",
 362                       cfg->psz_name, cfg->psz_value );
 363             continue;
 364         }
 365
 366         if( i_type != VLC_VAR_BOOL && cfg->psz_value == NULL )
 367         {
 368             msg_Warn( p_this, "missing value for option %s", cfg->psz_name );
 369             continue;
 370         }
 371         if( i_type != VLC_VAR_STRING && b_once )
 372         {
 373             msg_Warn( p_this, "*option_name need to be a string option" );
 374             continue;
 375         }
 376
 377         switch( i_type )
 378         {
 379             case VLC_VAR_BOOL:
 380                 val.b_bool = b_yes;
 381                 break;
 382             case VLC_VAR_INTEGER:
 383                 val.i_int = strtol( cfg->psz_value ? cfg->psz_value : "0",
 384                                     NULL, 0 );
 385                 break;
 386             case VLC_VAR_FLOAT:
 387                 val.f_float = us_atof( cfg->psz_value ? cfg->psz_value : "0" );
 388                 break;
 389             case VLC_VAR_STRING:
 390                 val.psz_string = cfg->psz_value;
 391                 break;
 392             default:
 393                 msg_Warn( p_this, "unhandled config var type (%d)", i_type );
 394                 memset( &val, 0, sizeof( vlc_value_t ) );
 395                 break;
 396         }
 397         if( b_once )
 398         {
 399             vlc_value_t val2;
 400
 401             var_Get( p_this, psz_name, &val2 );
 402             if( *val2.psz_string )
 403             {
 404                 free( val2.psz_string );
 405                 msg_Dbg( p_this, "ignoring option %s (not first occurrence)", psz_name );
 406                 continue;
 407             }
 408             free( val2.psz_string );
 409         }
 410         var_Set( p_this, psz_name, val );
 411         msg_Dbg( p_this, "set config option: %s to %s", psz_name,
 412                  cfg->psz_value ? cfg->psz_value : "(null)" );
 413     }
 414 }
 415
 416 config_chain_t *config_ChainDuplicate( const config_chain_t *p_src )
 417 {
 418     config_chain_t *p_dst = NULL;
 419     config_chain_t **pp_last = &p_dst;
 420
 421     for( ; p_src != NULL; p_src = p_src->p_next )
 422     {
 423         config_chain_t *p = malloc( sizeof(*p) );
 424         if( !p )
 425             break;
 426         p->p_next    = NULL;
 427         p->psz_name  = p_src->psz_name  ? strdup( p_src->psz_name )  : NULL;
 428         p->psz_value = p_src->psz_value ? strdup( p_src->psz_value ) : NULL;
 429
 430         *pp_last = p;
 431         pp_last = &p->p_next;
 432     }
 433     return p_dst;
 434 }
 435
 436 char *config_StringUnescape( char *psz_string )
 437 {
 438     char *psz_src = psz_string;
 439     char *psz_dst = psz_string;
 440     if( !psz_src )
 441         return NULL;
 442
 443     while( *psz_src )
 444     {
 445         if( IsEscape( psz_src ) )
 446             psz_src++;
 447         *psz_dst++ = *psz_src++;
 448     }
 449     *psz_dst = '\0';
 450
 451     return psz_string;
 452 }
 453
 454 char *config_StringEscape( const char *str )
 455 {
 456     size_t length = 0;
 457
 458     if( str == NULL )
 459         return NULL;
 460
 461     for( const char *p = str; *p; p++ )
 462         length += IsEscapeNeeded( *p ) ? 2 : 1;
 463
 464     char *ret = xmalloc( length + 1 ), *dst = ret;
 465     for( const char *p = str; *p; p++ )
 466     {
 467         if( IsEscapeNeeded( *p ) )
 468             *dst++ = '\\';
 469         *dst++ = *p;
 470     }
 471     *dst = '\0';;
 472     return ret;
 473 }