src/misc/messages.c

   1 /*****************************************************************************
   2  * messages.c: messages interface
   3  * This library provides an interface to the message queue to be used by other
   4  * modules, especially intf modules. See vlc_config.h for output configuration.
   5  *****************************************************************************
   6  * Copyright (C) 1998-2005 the VideoLAN team
   7  * $Id$
   8  *
   9  * Authors: Vincent Seguin <seguin@via.ecp.fr>
  10  *          Samuel Hocevar <sam@zoy.org>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  25  *****************************************************************************/
  26
  27 /*****************************************************************************
  28  * Preamble
  29  *****************************************************************************/
  30
  31 #ifdef HAVE_CONFIG_H
  32 # include "config.h"
  33 #endif
  34
  35 #include <vlc_common.h>
  36
  37 #include <stdarg.h>                                       /* va_list for BSD */
  38 #ifdef __APPLE__
  39 # include <xlocale.h>
  40 #elif defined(HAVE_LOCALE_H)
  41 # include <locale.h>
  42 #endif
  43 #include <errno.h>                                                  /* errno */
  44
  45 #ifdef WIN32
  46 #   include <vlc_network.h>          /* 'net_strerror' and 'WSAGetLastError' */
  47 #endif
  48
  49 #ifdef HAVE_UNISTD_H
  50 #   include <unistd.h>                                   /* close(), write() */
  51 #endif
  52
  53 #include <assert.h>
  54
  55 #include <vlc_charset.h>
  56 #include "../libvlc.h"
  57
  58 /*****************************************************************************
  59  * Local macros
  60  *****************************************************************************/
  61 #if defined(HAVE_VA_COPY)
  62 #   define vlc_va_copy(dest,src) va_copy(dest,src)
  63 #elif defined(HAVE___VA_COPY)
  64 #   define vlc_va_copy(dest,src) __va_copy(dest,src)
  65 #else
  66 #   define vlc_va_copy(dest,src) (dest)=(src)
  67 #endif
  68
  69 static inline msg_bank_t *libvlc_bank (libvlc_int_t *inst)
  70 {
  71     return (libvlc_priv (inst))->msg_bank;
  72 }
  73
  74 /*****************************************************************************
  75  * Local prototypes
  76  *****************************************************************************/
  77 static void PrintMsg ( vlc_object_t *, msg_item_t * );
  78
  79 /**
  80  * Store all data required by messages interfaces.
  81  */
  82 struct msg_bank_t
  83 {
  84     /** Message queue lock */
  85     vlc_rwlock_t lock;
  86
  87     /* Subscribers */
  88     int i_sub;
  89     msg_subscription_t **pp_sub;
  90
  91     locale_t locale; /**< C locale for error messages */
  92     vlc_dictionary_t enabled_objects; ///< Enabled objects
  93     bool all_objects_enabled; ///< Should we print all objects?
  94 };
  95
  96 /**
  97  * Initialize messages queues
  98  * This function initializes all message queues
  99  */
 100 msg_bank_t *msg_Create (void)
 101 {
 102     msg_bank_t *bank = malloc (sizeof (*bank));
 103
 104     vlc_rwlock_init (&bank->lock);
 105     vlc_dictionary_init (&bank->enabled_objects, 0);
 106     bank->all_objects_enabled = true;
 107
 108     bank->i_sub = 0;
 109     bank->pp_sub = NULL;
 110
 111     /* C locale to get error messages in English in the logs */
 112     bank->locale = newlocale (LC_MESSAGES_MASK, "C", (locale_t)0);
 113     return bank;
 114 }
 115
 116 /**
 117  * Object Printing selection
 118  */
 119 static void const * kObjectPrintingEnabled = &kObjectPrintingEnabled;
 120 static void const * kObjectPrintingDisabled = &kObjectPrintingDisabled;
 121
 122
 123 #undef msg_EnableObjectPrinting
 124 void msg_EnableObjectPrinting (vlc_object_t *obj, const char * psz_object)
 125 {
 126     msg_bank_t *bank = libvlc_bank (obj->p_libvlc);
 127
 128     vlc_rwlock_wrlock (&bank->lock);
 129     if( !strcmp(psz_object, "all") )
 130         bank->all_objects_enabled = true;
 131     else
 132         vlc_dictionary_insert (&bank->enabled_objects, psz_object,
 133                                (void *)kObjectPrintingEnabled);
 134     vlc_rwlock_unlock (&bank->lock);
 135 }
 136
 137 #undef msg_DisableObjectPrinting
 138 void msg_DisableObjectPrinting (vlc_object_t *obj, const char * psz_object)
 139 {
 140     msg_bank_t *bank = libvlc_bank (obj->p_libvlc);
 141
 142     vlc_rwlock_wrlock (&bank->lock);
 143     if( !strcmp(psz_object, "all") )
 144         bank->all_objects_enabled = false;
 145     else
 146         vlc_dictionary_insert (&bank->enabled_objects, psz_object,
 147                                (void *)kObjectPrintingDisabled);
 148     vlc_rwlock_unlock (&bank->lock);
 149 }
 150
 151 /**
 152  * Destroy the message queues
 153  *
 154  * This functions prints all messages remaining in the queues,
 155  * then frees all the allocated resources
 156  * No other messages interface functions should be called after this one.
 157  */
 158 void msg_Destroy (msg_bank_t *bank)
 159 {
 160     if (unlikely(bank->i_sub != 0))
 161         fputs ("stale interface subscribers (LibVLC might crash)\n", stderr);
 162
 163     if (bank->locale != (locale_t)0)
 164        freelocale (bank->locale);
 165
 166     vlc_dictionary_clear (&bank->enabled_objects, NULL, NULL);
 167
 168     vlc_rwlock_destroy (&bank->lock);
 169     free (bank);
 170 }
 171
 172 struct msg_subscription_t
 173 {
 174     libvlc_int_t   *instance;
 175     msg_callback_t  func;
 176     msg_cb_data_t  *opaque;
 177     int             verbosity;
 178 };
 179
 180 /**
 181  * Subscribe to the message queue.
 182  * Whenever a message is emitted, a callback will be called.
 183  * Callback invocation are serialized within a subscription.
 184  *
 185  * @param instance LibVLC instance to get messages from
 186  * @param cb callback function
 187  * @param opaque data for the callback function
 188  * @return a subscription pointer, or NULL in case of failure
 189  */
 190 msg_subscription_t *msg_Subscribe (libvlc_int_t *instance, msg_callback_t cb,
 191                                    msg_cb_data_t *opaque)
 192 {
 193     msg_subscription_t *sub = malloc (sizeof (*sub));
 194     if (sub == NULL)
 195         return NULL;
 196
 197     sub->instance = instance;
 198     sub->func = cb;
 199     sub->opaque = opaque;
 200     sub->verbosity = 2; /* by default, give all the messages */
 201
 202     msg_bank_t *bank = libvlc_bank (instance);
 203     vlc_rwlock_wrlock (&bank->lock);
 204     TAB_APPEND (bank->i_sub, bank->pp_sub, sub);
 205     vlc_rwlock_unlock (&bank->lock);
 206
 207     return sub;
 208 }
 209
 210 /**
 211  * Unsubscribe from the message queue.
 212  * This function waits for the message callback to return if needed.
 213  */
 214 void msg_Unsubscribe (msg_subscription_t *sub)
 215 {
 216     msg_bank_t *bank = libvlc_bank (sub->instance);
 217
 218     vlc_rwlock_wrlock (&bank->lock);
 219     TAB_REMOVE (bank->i_sub, bank->pp_sub, sub);
 220     vlc_rwlock_unlock (&bank->lock);
 221     free (sub);
 222 }
 223
 224 void msg_SubscriptionSetVerbosity( msg_subscription_t *sub, const int i_verbosity )
 225 {
 226     if( i_verbosity < 0 || i_verbosity > 2 ) return;
 227
 228     msg_bank_t *bank = libvlc_bank ( sub->instance );
 229
 230     vlc_rwlock_wrlock (&bank->lock);
 231
 232     sub->verbosity = i_verbosity;
 233
 234     vlc_rwlock_unlock (&bank->lock);
 235 }
 236 /*****************************************************************************
 237  * msg_*: print a message
 238  *****************************************************************************
 239  * These functions queue a message for later printing.
 240  *****************************************************************************/
 241 void msg_Generic( vlc_object_t *p_this, int i_type, const char *psz_module,
 242                     const char *psz_format, ... )
 243 {
 244     va_list args;
 245
 246     va_start( args, psz_format );
 247     msg_GenericVa (p_this, i_type, psz_module, psz_format, args);
 248     va_end( args );
 249 }
 250
 251 /**
 252  * Destroys a message.
 253  */
 254 static void msg_Free (gc_object_t *gc)
 255 {
 256     msg_item_t *msg = vlc_priv (gc, msg_item_t);
 257
 258     free (msg->psz_module);
 259     free (msg->psz_msg);
 260     free (msg->psz_header);
 261     free (msg);
 262 }
 263
 264 #undef msg_GenericVa
 265 /**
 266  * Add a message to a queue
 267  *
 268  * This function provides basic functionnalities to other msg_* functions.
 269  * It adds a message to a queue (after having printed all stored messages if it
 270  * is full). If the message can't be converted to string in memory, it issues
 271  * a warning.
 272  */
 273 void msg_GenericVa (vlc_object_t *p_this, int i_type,
 274                            const char *psz_module,
 275                            const char *psz_format, va_list _args)
 276 {
 277     size_t      i_header_size;             /* Size of the additionnal header */
 278     vlc_object_t *p_obj;
 279     char *       psz_str = NULL;                 /* formatted message string */
 280     char *       psz_header = NULL;
 281     va_list      args;
 282
 283     assert (p_this);
 284
 285     if( p_this->i_flags & OBJECT_FLAGS_QUIET ||
 286         (p_this->i_flags & OBJECT_FLAGS_NODBG && i_type == VLC_MSG_DBG) )
 287         return;
 288
 289     msg_bank_t *bank = libvlc_bank (p_this->p_libvlc);
 290     locale_t locale = uselocale (bank->locale);
 291
 292 #ifndef __GLIBC__
 293     /* Expand %m to strerror(errno) - only once */
 294     char buf[strlen( psz_format ) + 2001], *ptr;
 295     strcpy( buf, psz_format );
 296     ptr = (char*)buf;
 297     psz_format = (const char*) buf;
 298
 299     for( ;; )
 300     {
 301         ptr = strchr( ptr, '%' );
 302         if( ptr == NULL )
 303             break;
 304
 305         if( ptr[1] == 'm' )
 306         {
 307             char errbuf[2001];
 308             size_t errlen;
 309
 310 #ifndef WIN32
 311             strerror_r( errno, errbuf, 1001 );
 312 #else
 313             int sockerr = WSAGetLastError( );
 314             if( sockerr )
 315             {
 316                 strncpy( errbuf, net_strerror( sockerr ), 1001 );
 317                 WSASetLastError( sockerr );
 318             }
 319             if ((sockerr == 0)
 320              || (strcmp ("Unknown network stack error", errbuf) == 0))
 321                 strncpy( errbuf, strerror( errno ), 1001 );
 322 #endif
 323             errbuf[1000] = 0;
 324
 325             /* Escape '%' from the error string */
 326             for( char *percent = strchr( errbuf, '%' );
 327                  percent != NULL;
 328                  percent = strchr( percent + 2, '%' ) )
 329             {
 330                 memmove( percent + 1, percent, strlen( percent ) + 1 );
 331             }
 332
 333             errlen = strlen( errbuf );
 334             memmove( ptr + errlen, ptr + 2, strlen( ptr + 2 ) + 1 );
 335             memcpy( ptr, errbuf, errlen );
 336             break; /* Only once, so we don't overflow */
 337         }
 338
 339         /* Looks for conversion specifier... */
 340         do
 341             ptr++;
 342         while( *ptr && ( strchr( "diouxXeEfFgGaAcspn%", *ptr ) == NULL ) );
 343         if( *ptr )
 344             ptr++; /* ...and skip it */
 345     }
 346 #endif
 347
 348     /* Convert message to string  */
 349     vlc_va_copy( args, _args );
 350     if( vasprintf( &psz_str, psz_format, args ) == -1 )
 351         psz_str = NULL;
 352     va_end( args );
 353
 354     if( psz_str == NULL )
 355     {
 356         int canc = vlc_savecancel (); /* Do not print half of a message... */
 357 #ifdef __GLIBC__
 358         fprintf( stderr, "main warning: can't store message (%m): " );
 359 #else
 360         char psz_err[1001];
 361 #ifndef WIN32
 362         /* we're not using GLIBC, so we are sure that the error description
 363          * will be stored in the buffer we provide to strerror_r() */
 364         strerror_r( errno, psz_err, 1001 );
 365 #else
 366         strncpy( psz_err, strerror( errno ), 1001 );
 367 #endif
 368         psz_err[1000] = '\0';
 369         fprintf( stderr, "main warning: can't store message (%s): ", psz_err );
 370 #endif
 371         vlc_va_copy( args, _args );
 372         /* We should use utf8_vfprintf - but it calls malloc()... */
 373         vfprintf( stderr, psz_format, args );
 374         va_end( args );
 375         fputs( "\n", stderr );
 376         vlc_restorecancel (canc);
 377         uselocale (locale);
 378         return;
 379     }
 380     uselocale (locale);
 381
 382     msg_item_t * p_item = malloc (sizeof (*p_item));
 383     if (p_item == NULL)
 384         return; /* Uho! */
 385
 386     vlc_gc_init (p_item, msg_Free);
 387     p_item->psz_module = p_item->psz_msg = p_item->psz_header = NULL;
 388
 389
 390
 391     i_header_size = 0;
 392     p_obj = p_this;
 393     while( p_obj != NULL )
 394     {
 395         char *psz_old = NULL;
 396         if( p_obj->psz_header )
 397         {
 398             i_header_size += strlen( p_obj->psz_header ) + 4;
 399             if( psz_header )
 400             {
 401                 psz_old = strdup( psz_header );
 402                 psz_header = xrealloc( psz_header, i_header_size );
 403                 snprintf( psz_header, i_header_size , "[%s] %s",
 404                           p_obj->psz_header, psz_old );
 405             }
 406             else
 407             {
 408                 psz_header = xmalloc( i_header_size );
 409                 snprintf( psz_header, i_header_size, "[%s]",
 410                           p_obj->psz_header );
 411             }
 412         }
 413         free( psz_old );
 414         p_obj = p_obj->p_parent;
 415     }
 416
 417     /* Fill message information fields */
 418     p_item->i_type =        i_type;
 419     p_item->i_object_id =   (uintptr_t)p_this;
 420     p_item->psz_object_type = p_this->psz_object_type;
 421     p_item->psz_module =    strdup( psz_module );
 422     p_item->psz_msg =       psz_str;
 423     p_item->psz_header =    psz_header;
 424
 425     PrintMsg( p_this, p_item );
 426
 427     vlc_rwlock_rdlock (&bank->lock);
 428     for (int i = 0; i < bank->i_sub; i++)
 429     {
 430         msg_subscription_t *sub = bank->pp_sub[i];
 431         libvlc_priv_t *priv = libvlc_priv( sub->instance );
 432         msg_bank_t *bank = priv->msg_bank;
 433         void *val = vlc_dictionary_value_for_key( &bank->enabled_objects,
 434                                                   p_item->psz_module );
 435         if( val == kObjectPrintingDisabled ) continue;
 436         if( val != kObjectPrintingEnabled  ) /*if not allowed */
 437         {
 438             val = vlc_dictionary_value_for_key( &bank->enabled_objects,
 439                                                  p_item->psz_object_type );
 440             if( val == kObjectPrintingDisabled ) continue;
 441             if( val == kObjectPrintingEnabled  ); /* Allowed */
 442             else if( !bank->all_objects_enabled ) continue;
 443         }
 444         switch( p_item->i_type )
 445         {
 446             case VLC_MSG_INFO:
 447             case VLC_MSG_ERR:
 448                 if( sub->verbosity < 0 ) continue;
 449                 break;
 450             case VLC_MSG_WARN:
 451                 if( sub->verbosity < 1 ) continue;
 452                 break;
 453             case VLC_MSG_DBG:
 454                 if( sub->verbosity < 2 ) continue;
 455                 break;
 456         }
 457
 458         sub->func (sub->opaque, p_item, 0);
 459     }
 460     vlc_rwlock_unlock (&bank->lock);
 461     msg_Release (p_item);
 462 }
 463
 464 /*****************************************************************************
 465  * PrintMsg: output a standard message item to stderr
 466  *****************************************************************************
 467  * Print a message to stderr, with colour formatting if needed.
 468  *****************************************************************************/
 469 static void PrintMsg ( vlc_object_t * p_this, msg_item_t * p_item )
 470 {
 471 #   define COL(x,y)  "\033[" #x ";" #y "m"
 472 #   define RED     COL(31,1)
 473 #   define GREEN   COL(32,1)
 474 #   define YELLOW  COL(0,33)
 475 #   define WHITE   COL(0,1)
 476 #   define GRAY    "\033[0m"
 477
 478     static const char ppsz_type[4][9] = { "", " error", " warning", " debug" };
 479     static const char ppsz_color[4][8] = { WHITE, RED, YELLOW, GRAY };
 480     const char *psz_object;
 481     libvlc_priv_t *priv = libvlc_priv (p_this->p_libvlc);
 482     msg_bank_t *bank = priv->msg_bank;
 483     int i_type = p_item->i_type;
 484
 485     switch( i_type )
 486     {
 487         case VLC_MSG_ERR:
 488             if( priv->i_verbose < 0 ) return;
 489             break;
 490         case VLC_MSG_INFO:
 491             if( priv->i_verbose < 0 ) return;
 492             break;
 493         case VLC_MSG_WARN:
 494             if( priv->i_verbose < 1 ) return;
 495             break;
 496         case VLC_MSG_DBG:
 497             if( priv->i_verbose < 2 ) return;
 498             break;
 499     }
 500
 501     psz_object = p_item->psz_object_type;
 502     void * val = vlc_dictionary_value_for_key (&bank->enabled_objects,
 503                                                p_item->psz_module);
 504     if( val == kObjectPrintingDisabled )
 505         return;
 506     if( val == kObjectPrintingEnabled )
 507         /* Allowed */;
 508     else
 509     {
 510         val = vlc_dictionary_value_for_key (&bank->enabled_objects,
 511                                             psz_object);
 512         if( val == kObjectPrintingDisabled )
 513             return;
 514         if( val == kObjectPrintingEnabled )
 515             /* Allowed */;
 516         else if( !bank->all_objects_enabled )
 517             return;
 518     }
 519
 520     int canc = vlc_savecancel ();
 521     /* Send the message to stderr */
 522     utf8_fprintf( stderr, "[%s%p%s] %s%s%s %s%s: %s%s%s\n",
 523                   priv->b_color ? GREEN : "",
 524                   (void *)p_item->i_object_id,
 525                   priv->b_color ? GRAY : "",
 526                   p_item->psz_header ? p_item->psz_header : "",
 527                   p_item->psz_header ? " " : "",
 528                   p_item->psz_module, psz_object,
 529                   ppsz_type[i_type],
 530                   priv->b_color ? ppsz_color[i_type] : "",
 531                   p_item->psz_msg,
 532                   priv->b_color ? GRAY : "" );
 533
 534 #ifdef WIN32
 535     fflush( stderr );
 536 #endif
 537     vlc_restorecancel (canc);
 538 }