include/vlc_stream.h

   1 /*****************************************************************************
   2  * vlc_stream.h: Stream (between access and demux) descriptor and methods
   3  *****************************************************************************
   4  * Copyright (C) 1999-2004 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Laurent Aimar <fenrir@via.ecp.fr>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 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 General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 #ifndef VLC_STREAM_H
  25 #define VLC_STREAM_H 1
  26
  27 #include <vlc_block.h>
  28
  29 /**
  30  * \file
  31  * This file defines structures and functions for stream (between access and demux) descriptor in vlc
  32  */
  33
  34 # ifdef __cplusplus
  35 extern "C" {
  36 # endif
  37
  38 /**
  39  * \defgroup stream Stream
  40  *
  41  *  This will allow you to easily handle read/seek in demuxer modules.
  42  * @{
  43  */
  44
  45 /* Opaque definition for text reader context */
  46 typedef struct stream_text_t stream_text_t;
  47
  48 /**
  49  * stream_t definition
  50  */
  51
  52 struct stream_t
  53 {
  54     VLC_COMMON_MEMBERS
  55     bool        b_error;
  56
  57     /* Module properties for stream filter */
  58     module_t    *p_module;
  59
  60     char        *psz_access;
  61     /* Real or virtual path (it can only be changed during stream_t opening) */
  62     char        *psz_path;
  63
  64     /* Stream source for stream filter */
  65     stream_t *p_source;
  66
  67     /* */
  68     int      (*pf_read)   ( stream_t *, void *p_read, unsigned int i_read );
  69     int      (*pf_peek)   ( stream_t *, const uint8_t **pp_peek, unsigned int i_peek );
  70     int      (*pf_control)( stream_t *, int i_query, va_list );
  71
  72     /* */
  73     void     (*pf_destroy)( stream_t *);
  74
  75     /* Private data for module */
  76     stream_sys_t *p_sys;
  77
  78     /* Text reader state */
  79     stream_text_t *p_text;
  80
  81     /* Weak link to parent input */
  82     input_thread_t *p_input;
  83 };
  84
  85 /**
  86  * Possible commands to send to stream_Control() and stream_vaControl()
  87  */
  88 enum stream_query_e
  89 {
  90     /* capabilities */
  91     STREAM_CAN_SEEK,            /**< arg1= bool *   res=cannot fail*/
  92     STREAM_CAN_FASTSEEK,        /**< arg1= bool *   res=cannot fail*/
  93
  94     /* */
  95     STREAM_SET_POSITION,        /**< arg1= uint64_t       res=can fail  */
  96     STREAM_GET_POSITION,        /**< arg1= uint64_t *     res=cannot fail*/
  97
  98     STREAM_GET_SIZE,            /**< arg1= uint64_t *     res=cannot fail (0 if no sense)*/
  99
 100     /* Special for direct access control from demuxer.
 101      * XXX: avoid using it by all means */
 102     STREAM_CONTROL_ACCESS,  /* arg1= int i_access_query, args   res: can fail
 103                              if access unreachable or access control answer */
 104
 105     /* You should update size of source if any and then update size
 106      * FIXME find a way to avoid it */
 107     STREAM_UPDATE_SIZE,
 108
 109     /* */
 110     STREAM_GET_CONTENT_TYPE,    /**< arg1= char **         res=can fail */
 111
 112     /* XXX only data read through stream_Read/Block will be recorded */
 113     STREAM_SET_RECORD_STATE,     /**< arg1=bool, arg2=const char *psz_ext (if arg1 is true)  res=can fail */
 114 };
 115
 116 VLC_API int stream_Read( stream_t *s, void *p_read, int i_read );
 117 VLC_API int stream_Peek( stream_t *s, const uint8_t **pp_peek, int i_peek );
 118 VLC_API int stream_vaControl( stream_t *s, int i_query, va_list args );
 119 VLC_API void stream_Delete( stream_t *s );
 120 VLC_API int stream_Control( stream_t *s, int i_query, ... );
 121 VLC_API block_t * stream_Block( stream_t *s, int i_size );
 122 VLC_API char * stream_ReadLine( stream_t * );
 123
 124 /**
 125  * Get the current position in a stream
 126  */
 127 static inline int64_t stream_Tell( stream_t *s )
 128 {
 129     uint64_t i_pos;
 130     stream_Control( s, STREAM_GET_POSITION, &i_pos );
 131     if( i_pos >> 62 )
 132         return (int64_t)1 << 62;
 133     return i_pos;
 134 }
 135
 136 /**
 137  * Get the size of the stream.
 138  */
 139 static inline int64_t stream_Size( stream_t *s )
 140 {
 141     uint64_t i_pos;
 142     stream_Control( s, STREAM_GET_SIZE, &i_pos );
 143     if( i_pos >> 62 )
 144         return (int64_t)1 << 62;
 145     return i_pos;
 146 }
 147
 148 static inline int stream_Seek( stream_t *s, uint64_t i_pos )
 149 {
 150     return stream_Control( s, STREAM_SET_POSITION, i_pos );
 151 }
 152
 153 /**
 154  * Get the Content-Type of a stream, or NULL if unknown.
 155  * Result must be free()'d.
 156  */
 157 static inline char *stream_ContentType( stream_t *s )
 158 {
 159     char *res;
 160     if( stream_Control( s, STREAM_GET_CONTENT_TYPE, &res ) )
 161         return NULL;
 162     return res;
 163 }
 164
 165 /**
 166  * Create a special stream and a demuxer, this allows chaining demuxers
 167  * You must delete it using stream_Delete.
 168  */
 169 VLC_API stream_t * stream_DemuxNew( demux_t *p_demux, const char *psz_demux, es_out_t *out );
 170
 171 /**
 172  * Send data to a stream_t handle created by stream_DemuxNew.
 173  */
 174 VLC_API void stream_DemuxSend( stream_t *s, block_t *p_block );
 175
 176 /**
 177  * Create a stream_t reading from memory.
 178  * You must delete it using stream_Delete.
 179  */
 180 VLC_API stream_t * stream_MemoryNew(vlc_object_t *p_obj, uint8_t *p_buffer, uint64_t i_size, bool b_preserve_memory );
 181 #define stream_MemoryNew( a, b, c, d ) stream_MemoryNew( VLC_OBJECT(a), b, c, d )
 182
 183 /**
 184  * Create a stream_t reading from a URL.
 185  * You must delete it using stream_Delete.
 186  */
 187 VLC_API stream_t * stream_UrlNew(vlc_object_t *p_this, const char *psz_url );
 188 #define stream_UrlNew( a, b ) stream_UrlNew( VLC_OBJECT(a), b )
 189
 190
 191 /**
 192  * Try to add a stream filter to an open stream.
 193  * @return New stream to use, or NULL if the filter could not be added.
 194  **/
 195 VLC_API stream_t* stream_FilterNew( stream_t *p_source, const char *psz_stream_filter );
 196 /**
 197  * @}
 198  */
 199
 200 # ifdef __cplusplus
 201 }
 202 # endif
 203
 204 #endif