FFmpeg
md5proto.c
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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 "avformat.h"
27 #include "avio.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[64];
61  URLContext *out;
62  int i, err = 0;
63 
64  av_md5_final(c->md5, md5);
65  for (i = 0; i < sizeof(md5); i++)
66  snprintf(buf + i*2, 3, "%02x", md5[i]);
67  buf[i*2] = '\n';
68 
69  av_strstart(filename, "md5:", &filename);
70 
71  if (*filename) {
72  err = ffurl_open_whitelist(&out, filename, AVIO_FLAG_WRITE,
75  if (err)
76  return err;
77  err = ffurl_write(out, buf, i*2+1);
78  ffurl_close(out);
79  } else {
80  if (fwrite(buf, 1, i*2+1, stdout) < i*2+1)
81  err = AVERROR(errno);
82  }
83 
84  av_freep(&c->md5);
85 
86  return err;
87 }
88 
89 
91  .name = "md5",
92  .url_open = md5_open,
93  .url_write = md5_write,
94  .url_close = md5_close,
95  .priv_data_size = sizeof(struct MD5Context),
96 };
#define NULL
Definition: coverity.c:32
struct AVMD5 * md5
Definition: md5proto.c:31
Buffered I/O operations.
int ffurl_open_whitelist(URLContext **puc, const char *filename, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options, const char *whitelist, const char *blacklist, URLContext *parent)
Create an URLContext for accessing to the resource indicated by url, and open it. ...
Definition: avio.c:306
Memory handling functions.
int ffurl_write(URLContext *h, const unsigned char *buf, int size)
Write size bytes from buf to the resource accessed by h.
Definition: avio.c:420
AVIOInterruptCB interrupt_callback
Definition: url.h:47
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:675
void av_md5_update(AVMD5 *ctx, const uint8_t *src, int len)
Update hash value.
Definition: md5.c:154
struct AVMD5 * av_md5_alloc(void)
Allocate an AVMD5 context.
Definition: md5.c:48
uint8_t
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
ptrdiff_t size
Definition: opengl_enc.c:100
Definition: md5.c:40
const URLProtocol ff_md5_protocol
Definition: md5proto.c:90
static int md5_write(URLContext *h, const unsigned char *buf, int size)
Definition: md5proto.c:49
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
error code definitions
const char * protocol_whitelist
Definition: url.h:49
static int md5_open(URLContext *h, const char *filename, int flags)
Definition: md5proto.c:34
const char * protocol_blacklist
Definition: url.h:50
void av_md5_init(AVMD5 *ctx)
Initialize MD5 hashing.
Definition: md5.c:143
void * buf
Definition: avisynth_c.h:766
Definition: url.h:38
void * priv_data
Definition: url.h:41
static int md5_close(URLContext *h)
Definition: md5proto.c:56
#define snprintf
Definition: snprintf.h:34
void av_md5_final(AVMD5 *ctx, uint8_t *dst)
Finish hashing and output digest value.
Definition: md5.c:192
const char * name
Definition: url.h:55
#define flags(name, subs,...)
Definition: cbs_av1.c:561
int ffurl_close(URLContext *h)
Definition: avio.c:466
int av_strstart(const char *str, const char *pfx, const char **ptr)
Return non-zero if pfx is a prefix of str.
Definition: avstring.c:34
Main libavformat public API header.
char * filename
specified URL
Definition: url.h:42
FILE * out
Definition: movenc.c:54
Public header for MD5 hash function implementation.
#define av_freep(p)
unbuffered private I/O API
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions