modules/access/attachment.c

   1 /*****************************************************************************
   2  * attachment.c: Input reading an attachment.
   3  *****************************************************************************
   4  * Copyright (C) 2009 Laurent Aimar
   5  * $Id$
   6  *
   7  * Authors: 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 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27
  28 #ifdef HAVE_CONFIG_H
  29 # include "config.h"
  30 #endif
  31
  32 #include <vlc_common.h>
  33 #include <vlc_plugin.h>
  34 #include <vlc_access.h>
  35 #include <vlc_input.h>
  36
  37 /*****************************************************************************
  38  * Module descriptor
  39  *****************************************************************************/
  40 static int  Open (vlc_object_t *);
  41 static void Close(vlc_object_t *);
  42
  43 vlc_module_begin()
  44     set_shortname(N_("Attachment"))
  45     set_description(N_("Attachment input"))
  46     set_category(CAT_INPUT)
  47     set_subcategory(SUBCAT_INPUT_ACCESS)
  48
  49     set_capability("access", 0)
  50     add_shortcut("attachment")
  51     set_callbacks(Open, Close)
  52 vlc_module_end()
  53
  54 /*****************************************************************************
  55  * Local prototypes
  56  *****************************************************************************/
  57 static ssize_t Read(access_t *, void *, size_t);
  58 static int     Seek(access_t *, uint64_t);
  59 static int     Control(access_t *, int, va_list);
  60
  61 struct access_sys_t
  62 {
  63     input_attachment_t *attachment;
  64     size_t offset;
  65 };
  66
  67 /* */
  68 static int Open(vlc_object_t *object)
  69 {
  70     access_t     *access = (access_t *)object;
  71
  72     input_thread_t *input = access->p_input;
  73     if (!input)
  74         return VLC_EGENERIC;
  75
  76     access_sys_t *sys = vlc_malloc(object, sizeof (*sys));
  77     if (unlikely(sys == NULL))
  78         return VLC_ENOMEM;
  79
  80     if (input_Control(input, INPUT_GET_ATTACHMENT, &sys->attachment,
  81                       access->psz_location))
  82         sys->attachment = NULL;
  83
  84     if (sys->attachment == NULL) {
  85         msg_Err(access, "Failed to find the attachment '%s'",
  86                 access->psz_location);
  87         return VLC_EGENERIC;
  88     }
  89
  90     sys->offset = 0;
  91
  92     /* */
  93     access->pf_read    = Read;
  94     access->pf_block   = NULL;
  95     access->pf_control = Control;
  96     access->pf_seek    = Seek;
  97     access->p_sys      = sys;
  98     return VLC_SUCCESS;
  99 }
 100
 101 /* */
 102 static void Close(vlc_object_t *object)
 103 {
 104     access_t     *access = (access_t *)object;
 105     access_sys_t *sys = access->p_sys;
 106
 107     vlc_input_attachment_Delete(sys->attachment);
 108 }
 109
 110 /* */
 111 static ssize_t Read(access_t *access, void *buffer, size_t size)
 112 {
 113     access_sys_t *sys = access->p_sys;
 114     input_attachment_t *a = sys->attachment;
 115
 116     if (sys->offset >= (uint64_t)a->i_data)
 117         return 0;
 118
 119     const size_t copy = __MIN(size, a->i_data - sys->offset);
 120     memcpy(buffer, (uint8_t *)a->p_data + sys->offset, copy);
 121     sys->offset += copy;
 122     return copy;
 123 }
 124
 125 /* */
 126 static int Seek(access_t *access, uint64_t position)
 127 {
 128     access_sys_t *sys = access->p_sys;
 129     input_attachment_t *a = sys->attachment;
 130
 131     if (position > a->i_data)
 132         position = a->i_data;
 133
 134     sys->offset = position;
 135     return VLC_SUCCESS;
 136 }
 137
 138 /* */
 139 static int Control(access_t *access, int query, va_list args)
 140 {
 141     access_sys_t *sys = access->p_sys;
 142
 143     switch (query)
 144     {
 145     case STREAM_CAN_SEEK:
 146     case STREAM_CAN_FASTSEEK:
 147     case STREAM_CAN_PAUSE:
 148     case STREAM_CAN_CONTROL_PACE:
 149         *va_arg(args, bool *) = true;
 150         break;
 151     case STREAM_GET_SIZE:
 152         *va_arg(args, uint64_t *) = sys->attachment->i_data;
 153         break;
 154     case STREAM_GET_PTS_DELAY:
 155         *va_arg(args, int64_t *) = DEFAULT_PTS_DELAY;
 156         break;
 157     case STREAM_SET_PAUSE_STATE:
 158         return VLC_SUCCESS;
 159
 160     default:
 161         return VLC_EGENERIC;
 162     }
 163     return VLC_SUCCESS;
 164 }
 165