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#include "read.h"
#include "vint.h"
#include "ebml_float.h"
#include "ebml_unsigned.h"
#include "ebml_signed.h"
#include <limits.h>
#ifdef WA_VALIDATE
extern uint64_t max_id_length;
extern uint64_t max_size_length;
#endif
// returns bytes read. 0 means EOF
uint64_t read_vint(nsmkv::MKVReader *reader, uint64_t *val)
{
uint8_t data[9] = {0};
size_t bytes_read = 0;
reader->Read(data, 1, &bytes_read);
if (bytes_read != 1)
return 0;
uint8_t length = vint_get_number_bytes(data[0]);
reader->Read(data+1, length, &bytes_read);
if (bytes_read != length)
return 0;
*val = vint_read_ptr(data);
return bytes_read+1;
}
// returns bytes read. 0 means EOF
uint64_t read_ebml_node(nsmkv::MKVReader *reader, ebml_node *node)
{
uint64_t bytes_read = read_vint(reader, &node->id);
if (!bytes_read)
return 0;
bytes_read += read_vint(reader, &node->size);
return bytes_read;
}
uint64_t read_utf8(nsmkv::MKVReader *reader, uint64_t size, char **utf8)
{
if (utf8)
{
if (size == SIZE_MAX) // prevent integer overflow
return 0;
char *&val = *utf8;
val = (char *)calloc((size_t)size + 1, sizeof(char));
if (val)
{
val[size]=0;
size_t bytes_read;
reader->Read(val, (size_t)size, &bytes_read);
if (bytes_read != (size_t)size)
{
free(val);
return 0;
}
return size;
}
return 0; // actually, out of memory and not EOF, but still we should abort ASAP
}
else
{
reader->Skip(size);
return size;
}
}
#if 0
int fseek64(nsmkv::MKVReader *reader, int64_t pos, int whence)
{
switch(whence)
{
case SEEK_SET:
return fsetpos(f, &pos);
case SEEK_CUR:
{
fpos_t curpos=0;
int ret = fgetpos(f, &curpos);
if (ret != 0)
return ret;
pos+=curpos;
return fsetpos(f, &pos);
}
case SEEK_END:
{
return _fseeki64(f, pos, SEEK_END);
}
}
return 1;
}
int64_t ftell64(nsmkv::MKVReader *reader)
{
fpos_t pos;
if (fgetpos(f, &pos) == 0)
return pos;
else
return -1L;
}
#endif
uint64_t read_unsigned(nsmkv::MKVReader *reader, uint64_t size, uint64_t *val)
{
uint8_t data[8] = {0};
if (size == 0 || size > 8)
return 0;
size_t bytes_read = 0;
reader->Read(data, (size_t)size, &bytes_read);
if (bytes_read != size)
{
return 0;
}
*val = unsigned_read_ptr_len(size, data);
return size;
}
uint64_t read_float(nsmkv::MKVReader *reader, uint64_t size, double *val)
{
uint8_t data[10] = {0};
if (size == 0 || size > 10)
return 0;
size_t bytes_read = 0;
reader->Read(data, (size_t)size, &bytes_read);
if (bytes_read != size)
{
return 0;
}
*val = float_read_ptr_len(size, data);
return size;
}
uint64_t read_signed(nsmkv::MKVReader *reader, uint64_t size, int64_t *val)
{
uint8_t data[8] = {0};
if (size == 0 || size > 8)
return 0;
size_t bytes_read = 0;
reader->Read(data, (size_t)size, &bytes_read);
if (bytes_read != size)
{
return 0;
}
*val = signed_read_ptr_len(size, data);
return size;
}
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