Chiebot-Mirror
/
FFmpeg
mirror of https://github.com/FFmpeg/FFmpeg.git
8
0
Fork 0
Code Issues Projects Releases Wiki Activity

checksuming for nut & nice checksum API for libavformat

Browse Source 
Originally committed as revision 2969 to svn://svn.ffmpeg.org/ffmpeg/trunk
pull/126/head
Michael Niedermayer 21 years ago
parent 5e9b83f5d7
commit ee9f36a88e
4 changed files with 83 additions and 34 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 7
      libavformat/avio.h
  2. 24
      libavformat/aviobuf.c
  3. 6
      libavformat/crc.c
  4. 80
      libavformat/nut.c

7
libavformat/avio.h
Unescape View File

@ -78,6 +78,9 @@ typedef struct {
int write_flag; /* true if open for writing */
int is_streamed;
int max_packet_size;
unsigned long checksum;
unsigned char *checksum_ptr;
unsigned long (*update_checksum)(unsigned long checksum, const uint8_t *buf, unsigned int size);
} ByteIOContext;
int init_put_byte(ByteIOContext *s,
@ -150,6 +153,10 @@ int url_open_dyn_buf(ByteIOContext *s);
int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size);
int url_close_dyn_buf(ByteIOContext *s, uint8_t **pbuffer);
unsigned long get_checksum(ByteIOContext *s);
void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum);
unsigned long update_adler32(unsigned long adler, const uint8_t *buf, unsigned int len);
/* file.c */
extern URLProtocol file_protocol;
extern URLProtocol pipe_protocol;

24
libavformat/aviobuf.c
Unescape View File

@ -48,6 +48,8 @@ int init_put_byte(ByteIOContext *s,
s->eof_reached = 0;
s->is_streamed = 0;
s->max_packet_size = 0;
s->checksum_ptr= NULL;
s->update_checksum= NULL;
return 0;
}
@ -58,6 +60,10 @@ static void flush_buffer(ByteIOContext *s)
if (s->buf_ptr > s->buffer) {
if (s->write_packet)
s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
if(s->checksum_ptr){
s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
s->checksum_ptr= s->buffer;
}
s->pos += s->buf_ptr - s->buffer;
}
s->buf_ptr = s->buffer;
@ -243,6 +249,12 @@ static void fill_buffer(ByteIOContext *s)
/* no need to do anything if EOF already reached */
if (s->eof_reached)
return;
if(s->checksum_ptr){
s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
s->checksum_ptr= s->buffer;
}
len = s->read_packet(s->opaque, s->buffer, s->buffer_size);
if (len <= 0) {
/* do not modify buffer if EOF reached so that a seek back can
@ -255,6 +267,18 @@ static void fill_buffer(ByteIOContext *s)
}
}
unsigned long get_checksum(ByteIOContext *s){
s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
s->checksum_ptr= NULL;
return s->checksum;
}
void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){
s->update_checksum= update_checksum;
s->checksum= s->update_checksum(checksum, NULL, 0);
s->checksum_ptr= s->buf_ptr;
}
/* NOTE: return 0 if EOF, so you cannot use it if EOF handling is
necessary */
/* XXX: put an inline version */

6
libavformat/crc.c
Unescape View File

@ -33,7 +33,7 @@
#define DO8(buf) DO4(buf); DO4(buf);
#define DO16(buf) DO8(buf); DO8(buf);
static uint32_t adler32(uint32_t adler, const uint8_t *buf, unsigned int len)
unsigned long update_adler32(unsigned long adler, const uint8_t *buf, unsigned int len)
{
unsigned long s1 = adler & 0xffff;
unsigned long s2 = (adler >> 16) & 0xffff;
@ -66,7 +66,7 @@ static int crc_write_header(struct AVFormatContext *s)
CRCState *crc = s->priv_data;
/* init CRC */
crc->crcval = adler32(0, NULL, 0);
crc->crcval = update_adler32(0, NULL, 0);
return 0;
}
@ -76,7 +76,7 @@ static int crc_write_packet(struct AVFormatContext *s,
const uint8_t *buf, int size, int64_t pts)
{
CRCState *crc = s->priv_data;
crc->crcval = adler32(crc->crcval, buf, size);
crc->crcval = update_adler32(crc->crcval, buf, size);
return 0;
}

80
libavformat/nut.c
Unescape View File

@ -25,7 +25,6 @@
/*
* TODO:
* - checksumming
* - seeking
* - index writing
* - index packet reading support
@ -284,7 +283,7 @@ static int get_str(ByteIOContext *bc, char *string, int maxlen){
return 0;
}
static int get_packetheader(NUTContext *nut, ByteIOContext *bc, int prefix_length)
static int get_packetheader(NUTContext *nut, ByteIOContext *bc, int prefix_length, int calculate_checksum)
{
int64_t start, size, last_size;
start= url_ftell(bc) - prefix_length;
@ -293,6 +292,9 @@ static int get_packetheader(NUTContext *nut, ByteIOContext *bc, int prefix_lengt
av_log(nut->avf, AV_LOG_ERROR, "get_packetheader called at weird position\n");
return -1;
}
if(calculate_checksum)
init_checksum(bc, update_adler32, 0);
size= get_v(bc);
last_size= get_v(bc);
@ -308,6 +310,11 @@ static int get_packetheader(NUTContext *nut, ByteIOContext *bc, int prefix_lengt
return size;
}
static int check_checksum(ByteIOContext *bc){
unsigned long checksum= get_checksum(bc);
return checksum != get_be32(bc);
}
/**
*
*/
@ -352,13 +359,16 @@ static int put_str(ByteIOContext *bc, const char *string){
return 0;
}
static int put_packetheader(NUTContext *nut, ByteIOContext *bc, int max_size)
static int put_packetheader(NUTContext *nut, ByteIOContext *bc, int max_size, int calculate_checksum)
{
put_flush_packet(bc);
nut->last_packet_start= nut->packet_start;
nut->packet_start+= nut->written_packet_size;
nut->packet_size_pos = url_ftell(bc);
nut->written_packet_size = max_size;
if(calculate_checksum)
init_checksum(bc, update_adler32, 0);
/* packet header */
put_v(bc, nut->written_packet_size); /* forward ptr */
@ -367,11 +377,14 @@ static int put_packetheader(NUTContext *nut, ByteIOContext *bc, int max_size)
return 0;
}
static int update_packetheader(NUTContext *nut, ByteIOContext *bc, int additional_size){
static int update_packetheader(NUTContext *nut, ByteIOContext *bc, int additional_size, int calculate_checksum){
int64_t start= nut->packet_start;
int64_t cur= url_ftell(bc);
int size= cur - start + additional_size;
if(calculate_checksum)
size += 4;
if(size != nut->written_packet_size){
int i;
@ -384,6 +397,9 @@ static int update_packetheader(NUTContext *nut, ByteIOContext *bc, int additiona
url_fseek(bc, cur, SEEK_SET);
nut->written_packet_size= size; //FIXME may fail if multiple updates with differing sizes, as get_length may differ
if(calculate_checksum)
put_be32(bc, get_checksum(bc));
}
return 0;
@ -405,10 +421,10 @@ static int nut_write_header(AVFormatContext *s)
/* main header */
put_be64(bc, MAIN_STARTCODE);
put_packetheader(nut, bc, 120+5*256);
put_packetheader(nut, bc, 120+5*256, 1);
put_v(bc, 1); /* version */
put_v(bc, s->nb_streams);
put_v(bc, 3); /* checksum threshold */
put_v(bc, 3);
build_frame_code(s);
assert(nut->frame_code['N'].flags == 1);
@ -435,9 +451,7 @@ static int nut_write_header(AVFormatContext *s)
put_v(bc, j);
}
put_be32(bc, 0); /* FIXME: checksum */
update_packetheader(nut, bc, 0);
update_packetheader(nut, bc, 0, 1);
/* stream headers */
for (i = 0; i < s->nb_streams; i++)
@ -447,7 +461,7 @@ static int nut_write_header(AVFormatContext *s)
codec = &s->streams[i]->codec;
put_be64(bc, STREAM_STARTCODE);
put_packetheader(nut, bc, 120 + codec->extradata_size);
put_packetheader(nut, bc, 120 + codec->extradata_size, 1);
put_v(bc, i /*s->streams[i]->index*/);
put_v(bc, (codec->codec_type == CODEC_TYPE_AUDIO) ? 32 : 0);
if (codec->codec_tag)
@ -520,14 +534,13 @@ static int nut_write_header(AVFormatContext *s)
default:
break;
}
put_be32(bc, 0); /* FIXME: checksum */
update_packetheader(nut, bc, 0);
update_packetheader(nut, bc, 0, 1);
}
/* info header */
put_be64(bc, INFO_STARTCODE);
put_packetheader(nut, bc, 30+strlen(s->author)+strlen(s->title)+
strlen(s->comment)+strlen(s->copyright)+strlen(LIBAVFORMAT_IDENT));
strlen(s->comment)+strlen(s->copyright)+strlen(LIBAVFORMAT_IDENT), 1);
if (s->author[0])
{
put_v(bc, 9); /* type */
@ -553,9 +566,7 @@ static int nut_write_header(AVFormatContext *s)
put_str(bc, LIBAVFORMAT_IDENT);
put_v(bc, 0); /* eof info */
put_be32(bc, 0); /* FIXME: checksum */
update_packetheader(nut, bc, 0);
update_packetheader(nut, bc, 0, 1);
put_flush_packet(bc);
@ -594,7 +605,7 @@ static int nut_write_packet(AVFormatContext *s, int stream_index,
}
if(frame_type>0){
update_packetheader(nut, bc, 0);
update_packetheader(nut, bc, 0, 0);
reset(s);
full_pts=1;
}
@ -684,7 +695,7 @@ static int nut_write_packet(AVFormatContext *s, int stream_index,
put_byte(bc, frame_code);
if(frame_type>0)
put_packetheader(nut, bc, FFMAX(size+20, MAX_TYPE1_DISTANCE));
put_packetheader(nut, bc, FFMAX(size+20, MAX_TYPE1_DISTANCE), 0);
if(nut->frame_code[frame_code].stream_id_plus1 == 0)
put_v(bc, stream_index);
if (flags & FLAG_PTS){
@ -697,7 +708,7 @@ static int nut_write_packet(AVFormatContext *s, int stream_index,
put_v(bc, size / size_mul);
if(size > MAX_TYPE1_DISTANCE){
assert(frame_type > 0);
update_packetheader(nut, bc, size);
update_packetheader(nut, bc, size, 0);
}
put_buffer(bc, buf, size);
@ -712,7 +723,7 @@ static int nut_write_trailer(AVFormatContext *s)
NUTContext *nut = s->priv_data;
ByteIOContext *bc = &s->pb;
update_packetheader(nut, bc, 0);
update_packetheader(nut, bc, 0, 0);
#if 0
int i;
@ -722,11 +733,10 @@ static int nut_write_trailer(AVFormatContext *s)
for (i = 0; s->nb_streams; i++)
{
put_be64(bc, INDEX_STARTCODE);
put_packetheader(nut, bc, 64);
put_packetheader(nut, bc, 64, 1);
put_v(bc, s->streams[i]->id);
put_v(bc, ...);
put_be32(bc, 0); /* FIXME: checksum */
update_packetheader(nut, bc, 0);
update_packetheader(nut, bc, 0, 1);
}
#endif
@ -768,7 +778,7 @@ static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
tmp = get_be64(bc);
if (tmp != MAIN_STARTCODE)
av_log(s, AV_LOG_ERROR, "damaged? startcode!=1 (%Ld)\n", tmp);
get_packetheader(nut, bc, 8);
get_packetheader(nut, bc, 8, 1);
tmp = get_v(bc);
if (tmp != 1)
@ -821,7 +831,10 @@ static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
return -1;
}
get_be32(bc); /* checkusm */
if(check_checksum(bc)){
av_log(s, AV_LOG_ERROR, "Main header checksum missmatch\n");
return -1;
}
s->bit_rate = 0;
@ -836,7 +849,7 @@ static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
tmp = get_be64(bc);
if (tmp != STREAM_STARTCODE)
av_log(s, AV_LOG_ERROR, "damaged? startcode!=1 (%Ld)\n", tmp);
get_packetheader(nut, bc, 8);
get_packetheader(nut, bc, 8, 1);
st = av_new_stream(s, get_v(bc));
if (!st)
return AVERROR_NOMEM;
@ -895,14 +908,17 @@ static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
st->codec.sample_rate = (get_v(bc) * nom) / denom;
st->codec.channels = get_v(bc);
}
get_be32(bc); /* checksum */
if(check_checksum(bc)){
av_log(s, AV_LOG_ERROR, "Stream header %d checksum missmatch\n", cur_stream);
return -1;
}
nut->stream[cur_stream].rate_num= nom;
nut->stream[cur_stream].rate_den= denom;
}
tmp = get_be64(bc);
if (tmp == INFO_STARTCODE){
get_packetheader(nut, bc, 8);
get_packetheader(nut, bc, 8, 1);
for(;;){
int id= get_v(bc);
@ -943,7 +959,9 @@ static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
get_str(bc, NULL, 0);
}
}
get_be32(bc); /* checksum */
if(check_checksum(bc)){
av_log(s, AV_LOG_ERROR, "Info header checksum missmatch\n");
}
}else
url_fseek(bc, -8, SEEK_CUR);
@ -986,9 +1004,9 @@ static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
if(flags & FLAG_FRAME_TYPE){
reset(s);
if(frame_type==2){
get_packetheader(nut, bc, 8+1);
get_packetheader(nut, bc, 8+1, 0);
}else{
get_packetheader(nut, bc, 1);
get_packetheader(nut, bc, 1, 0);
frame_type= 1;
}
}

Write Preview
Loading…
Cancel
Save