libavformat/md5proto.c

   1 /*
   2  * Copyright (c) 2010 Mans Rullgard
   3  *
   4  * This file is part of FFmpeg.
   5  *
   6  * FFmpeg is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * FFmpeg is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with FFmpeg; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include <stdio.h>
  22 #include "libavutil/avstring.h"
  23 #include "libavutil/md5.h"
  24 #include "libavutil/mem.h"
  25 #include "libavutil/error.h"
  26 #include "avio.h"
  27 #include "internal.h"
  28 #include "url.h"
  29
  30 struct MD5Context {
  31     struct AVMD5 *md5;
  32 };
  33
  34 static int md5_open(URLContext *h, const char *filename, int flags)
  35 {
  36     struct MD5Context *c = h->priv_data;
  37
  38     if (!(flags & AVIO_FLAG_WRITE))
  39         return AVERROR(EINVAL);
  40
  41     c->md5 = av_md5_alloc();
  42     if (!c->md5)
  43         return AVERROR(ENOMEM);
  44     av_md5_init(c->md5);
  45
  46     return 0;
  47 }
  48
  49 static int md5_write(URLContext *h, const unsigned char *buf, int size)
  50 {
  51     struct MD5Context *c = h->priv_data;
  52     av_md5_update(c->md5, buf, size);
  53     return size;
  54 }
  55
  56 static int md5_close(URLContext *h)
  57 {
  58     struct MD5Context *c = h->priv_data;
  59     const char *filename = h->filename;
  60     uint8_t md5[16], buf[2 * sizeof(md5) + 1];
  61     URLContext *out;
  62     int err = 0;
  63
  64     av_md5_final(c->md5, md5);
  65     ff_data_to_hex(buf, md5, sizeof(md5), 1);
  66     buf[2 * sizeof(md5)] = '\n';
  67
  68     av_strstart(filename, "md5:", &filename);
  69
  70     if (*filename) {
  71         err = ffurl_open_whitelist(&out, filename, AVIO_FLAG_WRITE,
  72                                    &h->interrupt_callback, NULL,
  73                                    h->protocol_whitelist, h->protocol_blacklist, h);
  74         if (err)
  75             return err;
  76         err = ffurl_write(out, buf, sizeof(buf));
  77         ffurl_close(out);
  78     } else {
  79         if (fwrite(buf, 1, sizeof(buf), stdout) < sizeof(buf))
  80             err = AVERROR(errno);
  81     }
  82
  83     av_freep(&c->md5);
  84
  85     return err;
  86 }
  87
  88
  89 const URLProtocol ff_md5_protocol = {
  90     .name                = "md5",
  91     .url_open            = md5_open,
  92     .url_write           = md5_write,
  93     .url_close           = md5_close,
  94     .priv_data_size      = sizeof(struct MD5Context),
  95 };