src/input/access.c

   1 /*****************************************************************************
   2  * access.c
   3  *****************************************************************************
   4  * Copyright (C) 1999-2008 VLC authors and VideoLAN
   5  * $Id$
   6  *
   7  * Author: Laurent Aimar <fenrir _AT_ videolan _DOT_ 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 <assert.h>
  29 #include <stdlib.h>
  30 #include <string.h>
  31
  32 #include <vlc_common.h>
  33 #include <vlc_url.h>
  34 #include <vlc_modules.h>
  35 #include <vlc_interrupt.h>
  36
  37 #include <libvlc.h>
  38 #include "stream.h"
  39 #include "input_internal.h"
  40
  41 /* Decode URL (which has had its scheme stripped earlier) to a file path. */
  42 char *get_path(const char *location)
  43 {
  44     char *url, *path;
  45
  46     /* Prepending "file://" is a bit hackish. But then again, we do not want
  47      * to hard-code the list of schemes that use file paths in vlc_uri2path().
  48      */
  49     if (asprintf(&url, "file://%s", location) == -1)
  50         return NULL;
  51
  52     path = vlc_uri2path (url);
  53     free (url);
  54     return path;
  55 }
  56
  57 static void vlc_access_Destroy(stream_t *access)
  58 {
  59     module_unneed(access, access->p_module);
  60     free(access->psz_filepath);
  61     free(access->psz_name);
  62 }
  63
  64 #define MAX_REDIR 5
  65
  66 /*****************************************************************************
  67  * access_New:
  68  *****************************************************************************/
  69 static stream_t *access_New(vlc_object_t *parent, input_thread_t *input,
  70                             bool preparsing, const char *mrl)
  71 {
  72     char *redirv[MAX_REDIR];
  73     unsigned redirc = 0;
  74
  75     stream_t *access = vlc_stream_CommonNew(parent, vlc_access_Destroy);
  76     if (unlikely(access == NULL))
  77         return NULL;
  78
  79     access->p_input = input;
  80     access->psz_name = NULL;
  81     access->psz_url = strdup(mrl);
  82     access->psz_filepath = NULL;
  83     access->b_preparsing = preparsing;
  84
  85     if (unlikely(access->psz_url == NULL))
  86         goto error;
  87
  88     while (redirc < MAX_REDIR)
  89     {
  90         char *url = access->psz_url;
  91         msg_Dbg(access, "creating access: %s", url);
  92
  93         const char *p = strstr(url, "://");
  94         if (p == NULL)
  95             goto error;
  96
  97         access->psz_name = strndup(url, p - url);
  98         if (unlikely(access->psz_name == NULL))
  99             goto error;
 100
 101         access->psz_location = p + 3;
 102         access->psz_filepath = get_path(access->psz_location);
 103         if (access->psz_filepath != NULL)
 104             msg_Dbg(access, " (path: %s)", access->psz_filepath);
 105
 106         access->p_module = module_need(access, "access", access->psz_name,
 107                                        true);
 108         if (access->p_module != NULL) /* success */
 109         {
 110             while (redirc > 0)
 111                 free(redirv[--redirc]);
 112
 113             assert(access->pf_control != NULL);
 114             return access;
 115         }
 116
 117         if (access->psz_url == url) /* failure (no redirection) */
 118             goto error;
 119
 120         /* redirection */
 121         msg_Dbg(access, "redirecting to: %s", access->psz_url);
 122         redirv[redirc++] = url;
 123
 124         for (unsigned j = 0; j < redirc; j++)
 125             if (!strcmp(redirv[j], access->psz_url))
 126             {
 127                 msg_Err(access, "redirection loop");
 128                 goto error;
 129             }
 130
 131         free(access->psz_filepath);
 132         free(access->psz_name);
 133         access->psz_filepath = access->psz_name = NULL;
 134     }
 135
 136     msg_Err(access, "too many redirections");
 137 error:
 138     while (redirc > 0)
 139         free(redirv[--redirc]);
 140     free(access->psz_filepath);
 141     free(access->psz_name);
 142     stream_CommonDelete(access);
 143     return NULL;
 144 }
 145
 146 stream_t *vlc_access_NewMRL(vlc_object_t *parent, const char *mrl)
 147 {
 148     return access_New(parent, NULL, false, mrl);
 149 }
 150
 151 /*****************************************************************************
 152  * access_vaDirectoryControlHelper:
 153  *****************************************************************************/
 154 int access_vaDirectoryControlHelper( stream_t *p_access, int i_query, va_list args )
 155 {
 156     VLC_UNUSED( p_access );
 157
 158     switch( i_query )
 159     {
 160         case STREAM_CAN_SEEK:
 161         case STREAM_CAN_FASTSEEK:
 162         case STREAM_CAN_PAUSE:
 163         case STREAM_CAN_CONTROL_PACE:
 164             *va_arg( args, bool* ) = false;
 165             break;
 166         case STREAM_GET_PTS_DELAY:
 167             *va_arg( args, int64_t * ) = 0;
 168             break;
 169         case STREAM_IS_DIRECTORY:
 170             break;
 171         default:
 172             return VLC_EGENERIC;
 173      }
 174      return VLC_SUCCESS;
 175 }
 176
 177 static int AStreamNoReadDir(stream_t *s, input_item_node_t *p_node)
 178 {
 179     (void) s; (void) p_node;
 180     return VLC_EGENERIC;;
 181 }
 182
 183 /* Block access */
 184 static block_t *AStreamReadBlock(stream_t *s, bool *restrict eof)
 185 {
 186     stream_t *access = s->p_sys;
 187     input_thread_t *input = s->p_input;
 188     block_t * block;
 189
 190     if (vlc_stream_Eof(access))
 191     {
 192         *eof = true;
 193         return NULL;
 194     }
 195     if (vlc_killed())
 196         return NULL;
 197
 198     block = vlc_stream_ReadBlock(access);
 199
 200     if (block != NULL && input != NULL)
 201     {
 202         struct input_stats *stats = input_priv(input)->stats;
 203
 204         if (stats != NULL)
 205         {
 206             vlc_mutex_lock(&stats->lock);
 207             input_rate_Add(&stats->input_bitrate, block->i_buffer);
 208             vlc_mutex_unlock(&stats->lock);
 209         }
 210     }
 211
 212     return block;
 213 }
 214
 215 /* Read access */
 216 static ssize_t AStreamReadStream(stream_t *s, void *buf, size_t len)
 217 {
 218     stream_t *access = s->p_sys;
 219     input_thread_t *input = s->p_input;
 220
 221     if (vlc_stream_Eof(access))
 222         return 0;
 223     if (vlc_killed())
 224         return -1;
 225
 226     ssize_t val = vlc_stream_ReadPartial(access, buf, len);
 227
 228     if (val > 0 && input != NULL)
 229     {
 230         struct input_stats *stats = input_priv(input)->stats;
 231
 232         if (stats != NULL)
 233         {
 234             vlc_mutex_lock(&stats->lock);
 235             input_rate_Add(&stats->input_bitrate, val);
 236             vlc_mutex_unlock(&stats->lock);
 237         }
 238     }
 239
 240     return val;
 241 }
 242
 243 /* Directory */
 244 static int AStreamReadDir(stream_t *s, input_item_node_t *p_node)
 245 {
 246     stream_t *access = s->p_sys;
 247
 248     return access->pf_readdir(access, p_node);
 249 }
 250
 251 /* Common */
 252 static int AStreamSeek(stream_t *s, uint64_t offset)
 253 {
 254     stream_t *access = s->p_sys;
 255
 256     return vlc_stream_Seek(access, offset);
 257 }
 258
 259 static int AStreamControl(stream_t *s, int cmd, va_list args)
 260 {
 261     stream_t *access = s->p_sys;
 262
 263     return vlc_stream_vaControl(access, cmd, args);
 264 }
 265
 266 static void AStreamDestroy(stream_t *s)
 267 {
 268     stream_t *access = s->p_sys;
 269
 270     vlc_stream_Delete(access);
 271 }
 272
 273 stream_t *stream_AccessNew(vlc_object_t *parent, input_thread_t *input,
 274                            bool preparsing, const char *url)
 275 {
 276     stream_t *s = vlc_stream_CommonNew(parent, AStreamDestroy);
 277     if (unlikely(s == NULL))
 278         return NULL;
 279
 280     stream_t *access = access_New(VLC_OBJECT(s), input, preparsing, url);
 281     if (access == NULL)
 282     {
 283         stream_CommonDelete(s);
 284         return NULL;
 285     }
 286
 287     s->p_input = input;
 288     s->psz_url = strdup(access->psz_url);
 289
 290     const char *cachename;
 291
 292     if (access->pf_block != NULL)
 293     {
 294         s->pf_block = AStreamReadBlock;
 295         cachename = "prefetch,cache_block";
 296     }
 297     else
 298     if (access->pf_read != NULL)
 299     {
 300         s->pf_read = AStreamReadStream;
 301         cachename = "prefetch,cache_read";
 302     }
 303     else
 304     {
 305         cachename = NULL;
 306     }
 307
 308     if (access->pf_readdir != NULL)
 309         s->pf_readdir = AStreamReadDir;
 310     else
 311         s->pf_readdir = AStreamNoReadDir;
 312
 313     s->pf_seek    = AStreamSeek;
 314     s->pf_control = AStreamControl;
 315     s->p_sys      = access;
 316
 317     if (cachename != NULL)
 318         s = stream_FilterChainNew(s, cachename);
 319     return stream_FilterAutoNew(s);
 320 }