/* 7zStream.c -- 7z Stream functions | |
2013-11-12 : Igor Pavlov : Public domain */ | |
#include "Precomp.h" | |
#include <string.h> | |
#include "7zTypes.h" | |
SRes SeqInStream_Read2(ISeqInStream *stream, void *buf, size_t size, SRes errorType) | |
{ | |
while (size != 0) | |
{ | |
size_t processed = size; | |
RINOK(stream->Read(stream, buf, &processed)); | |
if (processed == 0) | |
return errorType; | |
buf = (void *)((Byte *)buf + processed); | |
size -= processed; | |
} | |
return SZ_OK; | |
} | |
SRes SeqInStream_Read(ISeqInStream *stream, void *buf, size_t size) | |
{ | |
return SeqInStream_Read2(stream, buf, size, SZ_ERROR_INPUT_EOF); | |
} | |
SRes SeqInStream_ReadByte(ISeqInStream *stream, Byte *buf) | |
{ | |
size_t processed = 1; | |
RINOK(stream->Read(stream, buf, &processed)); | |
return (processed == 1) ? SZ_OK : SZ_ERROR_INPUT_EOF; | |
} | |
SRes LookInStream_SeekTo(ILookInStream *stream, UInt64 offset) | |
{ | |
Int64 t = offset; | |
return stream->Seek(stream, &t, SZ_SEEK_SET); | |
} | |
SRes LookInStream_LookRead(ILookInStream *stream, void *buf, size_t *size) | |
{ | |
const void *lookBuf; | |
if (*size == 0) | |
return SZ_OK; | |
RINOK(stream->Look(stream, &lookBuf, size)); | |
memcpy(buf, lookBuf, *size); | |
return stream->Skip(stream, *size); | |
} | |
SRes LookInStream_Read2(ILookInStream *stream, void *buf, size_t size, SRes errorType) | |
{ | |
while (size != 0) | |
{ | |
size_t processed = size; | |
RINOK(stream->Read(stream, buf, &processed)); | |
if (processed == 0) | |
return errorType; | |
buf = (void *)((Byte *)buf + processed); | |
size -= processed; | |
} | |
return SZ_OK; | |
} | |
SRes LookInStream_Read(ILookInStream *stream, void *buf, size_t size) | |
{ | |
return LookInStream_Read2(stream, buf, size, SZ_ERROR_INPUT_EOF); | |
} | |
static SRes LookToRead_Look_Lookahead(void *pp, const void **buf, size_t *size) | |
{ | |
SRes res = SZ_OK; | |
CLookToRead *p = (CLookToRead *)pp; | |
size_t size2 = p->size - p->pos; | |
if (size2 == 0 && *size > 0) | |
{ | |
p->pos = 0; | |
size2 = LookToRead_BUF_SIZE; | |
res = p->realStream->Read(p->realStream, p->buf, &size2); | |
p->size = size2; | |
} | |
if (size2 < *size) | |
*size = size2; | |
*buf = p->buf + p->pos; | |
return res; | |
} | |
static SRes LookToRead_Look_Exact(void *pp, const void **buf, size_t *size) | |
{ | |
SRes res = SZ_OK; | |
CLookToRead *p = (CLookToRead *)pp; | |
size_t size2 = p->size - p->pos; | |
if (size2 == 0 && *size > 0) | |
{ | |
p->pos = 0; | |
if (*size > LookToRead_BUF_SIZE) | |
*size = LookToRead_BUF_SIZE; | |
res = p->realStream->Read(p->realStream, p->buf, size); | |
size2 = p->size = *size; | |
} | |
if (size2 < *size) | |
*size = size2; | |
*buf = p->buf + p->pos; | |
return res; | |
} | |
static SRes LookToRead_Skip(void *pp, size_t offset) | |
{ | |
CLookToRead *p = (CLookToRead *)pp; | |
p->pos += offset; | |
return SZ_OK; | |
} | |
static SRes LookToRead_Read(void *pp, void *buf, size_t *size) | |
{ | |
CLookToRead *p = (CLookToRead *)pp; | |
size_t rem = p->size - p->pos; | |
if (rem == 0) | |
return p->realStream->Read(p->realStream, buf, size); | |
if (rem > *size) | |
rem = *size; | |
memcpy(buf, p->buf + p->pos, rem); | |
p->pos += rem; | |
*size = rem; | |
return SZ_OK; | |
} | |
static SRes LookToRead_Seek(void *pp, Int64 *pos, ESzSeek origin) | |
{ | |
CLookToRead *p = (CLookToRead *)pp; | |
p->pos = p->size = 0; | |
return p->realStream->Seek(p->realStream, pos, origin); | |
} | |
void LookToRead_CreateVTable(CLookToRead *p, int lookahead) | |
{ | |
p->s.Look = lookahead ? | |
LookToRead_Look_Lookahead : | |
LookToRead_Look_Exact; | |
p->s.Skip = LookToRead_Skip; | |
p->s.Read = LookToRead_Read; | |
p->s.Seek = LookToRead_Seek; | |
} | |
void LookToRead_Init(CLookToRead *p) | |
{ | |
p->pos = p->size = 0; | |
} | |
static SRes SecToLook_Read(void *pp, void *buf, size_t *size) | |
{ | |
CSecToLook *p = (CSecToLook *)pp; | |
return LookInStream_LookRead(p->realStream, buf, size); | |
} | |
void SecToLook_CreateVTable(CSecToLook *p) | |
{ | |
p->s.Read = SecToLook_Read; | |
} | |
static SRes SecToRead_Read(void *pp, void *buf, size_t *size) | |
{ | |
CSecToRead *p = (CSecToRead *)pp; | |
return p->realStream->Read(p->realStream, buf, size); | |
} | |
void SecToRead_CreateVTable(CSecToRead *p) | |
{ | |
p->s.Read = SecToRead_Read; | |
} |