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bytestream: Add bytestream2 writing API.

Signed-off-by: Justin Ruggles <justin.ruggles@gmail.com>
This commit is contained in:
Aneesh Dogra 2012-02-07 01:39:22 +05:30 committed by Justin Ruggles
parent d016d3074c
commit db7d45237a

View File

@ -1,6 +1,7 @@
/*
* Bytestream functions
* copyright (c) 2006 Baptiste Coudurier <baptiste.coudurier@free.fr>
* Copyright (c) 2012 Aneesh Dogra (lionaneesh) <lionaneesh@gmail.com>
*
* This file is part of Libav.
*
@ -30,6 +31,11 @@ typedef struct {
const uint8_t *buffer, *buffer_end, *buffer_start;
} GetByteContext;
typedef struct {
uint8_t *buffer, *buffer_end, *buffer_start;
int eof;
} PutByteContext;
#define DEF_T(type, name, bytes, read, write) \
static av_always_inline type bytestream_get_ ## name(const uint8_t **b){\
(*b) += bytes;\
@ -39,6 +45,17 @@ static av_always_inline void bytestream_put_ ##name(uint8_t **b, const type valu
write(*b, value);\
(*b) += bytes;\
}\
static av_always_inline void bytestream2_put_ ## name ## u(PutByteContext *p, const type value)\
{\
bytestream_put_ ## name(&p->buffer, value);\
}\
static av_always_inline void bytestream2_put_ ## name(PutByteContext *p, const type value){\
if (!p->eof && (p->buffer_end - p->buffer >= bytes)) {\
write(p->buffer, value);\
p->buffer += bytes;\
} else\
p->eof = 1;\
}\
static av_always_inline type bytestream2_get_ ## name ## u(GetByteContext *g)\
{\
return bytestream_get_ ## name(&g->buffer);\
@ -119,22 +136,53 @@ static av_always_inline void bytestream2_init(GetByteContext *g,
g->buffer_end = buf + buf_size;
}
static av_always_inline void bytestream2_init_writer(PutByteContext *p,
uint8_t *buf, int buf_size)
{
p->buffer = buf;
p->buffer_start = buf;
p->buffer_end = buf + buf_size;
p->eof = 0;
}
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
{
return g->buffer_end - g->buffer;
}
static av_always_inline unsigned int bytestream2_get_bytes_left_p(PutByteContext *p)
{
return p->buffer_end - p->buffer;
}
static av_always_inline void bytestream2_skip(GetByteContext *g,
unsigned int size)
{
g->buffer += FFMIN(g->buffer_end - g->buffer, size);
}
static av_always_inline void bytestream2_skip_p(PutByteContext *p,
unsigned int size)
{
int size2;
if (p->eof)
return;
size2 = FFMIN(p->buffer_end - p->buffer, size);
if (size2 != size)
p->eof = 1;
p->buffer += size2;
}
static av_always_inline int bytestream2_tell(GetByteContext *g)
{
return (int)(g->buffer - g->buffer_start);
}
static av_always_inline int bytestream2_tell_p(PutByteContext *p)
{
return (int)(p->buffer - p->buffer_start);
}
static av_always_inline int bytestream2_seek(GetByteContext *g, int offset,
int whence)
{
@ -158,6 +206,36 @@ static av_always_inline int bytestream2_seek(GetByteContext *g, int offset,
return bytestream2_tell(g);
}
static av_always_inline int bytestream2_seek_p(PutByteContext *p, int offset,
int whence)
{
p->eof = 0;
switch (whence) {
case SEEK_CUR:
if (p->buffer_end - p->buffer < offset)
p->eof = 1;
offset = av_clip(offset, -(p->buffer - p->buffer_start),
p->buffer_end - p->buffer);
p->buffer += offset;
break;
case SEEK_END:
if (offset > 0)
p->eof = 1;
offset = av_clip(offset, -(p->buffer_end - p->buffer_start), 0);
p->buffer = p->buffer_end + offset;
break;
case SEEK_SET:
if (p->buffer_end - p->buffer_start < offset)
p->eof = 1;
offset = av_clip(offset, 0, p->buffer_end - p->buffer_start);
p->buffer = p->buffer_start + offset;
break;
default:
return AVERROR(EINVAL);
}
return bytestream2_tell_p(p);
}
static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g,
uint8_t *dst,
unsigned int size)
@ -168,6 +246,40 @@ static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g,
return size2;
}
static av_always_inline unsigned int bytestream2_put_buffer(PutByteContext *p,
const uint8_t *src,
unsigned int size)
{
int size2;
if (p->eof)
return 0;
size2 = FFMIN(p->buffer_end - p->buffer, size);
if (size2 != size)
p->eof = 1;
memcpy(p->buffer, src, size2);
p->buffer += size2;
return size2;
}
static av_always_inline void bytestream2_set_buffer(PutByteContext *p,
const uint8_t c,
unsigned int size)
{
int size2;
if (p->eof)
return;
size2 = FFMIN(p->buffer_end - p->buffer, size);
if (size2 != size)
p->eof = 1;
memset(p->buffer, c, size2);
p->buffer += size2;
}
static av_always_inline unsigned int bytestream2_get_eof(PutByteContext *p)
{
return p->eof;
}
static av_always_inline unsigned int bytestream_get_buffer(const uint8_t **b, uint8_t *dst, unsigned int size)
{
memcpy(dst, *b, size);