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#include "SegmentInfo.h"
#include "read.h"
#include "global_elements.h"
#include <time.h>
#include <TCHAR.h>
#include <sys/stat.h>
int FileExists(const char * filename);
// returns bytes read. 0 means EOF
uint64_t nsmkv::ReadSegmentInfo(nsmkv::MKVReader *reader, uint64_t size, nsmkv::SegmentInfo &segment_info)
{
uint64_t total_bytes_read=0;
while (size)
{
ebml_node node;
uint64_t bytes_read = read_ebml_node(reader, &node);
if (bytes_read == 0)
return 0;
// benski> checking bytes_read and node.size separately prevents possible integer overflow attack
if (bytes_read > size)
return 0;
total_bytes_read+=bytes_read;
size-=bytes_read;
if (node.size > size)
return 0;
total_bytes_read+=node.size;
size-=node.size;
switch(node.id)
{
case mkv_segmentinfo_timecodescale:
{
uint64_t val;
if (read_unsigned(reader, node.size, &val) == 0)
return 0;
#ifdef WA_VALIDATE
printf(" Time Code Scale: %I64u\n", val);
segment_info.time_code_scale_found = true;
#endif
segment_info.time_code_scale = val;
}
break;
case mkv_segmentinfo_muxingapp:
{
char *utf8 = 0;
if (node.size && read_utf8(reader, node.size, &utf8) == 0)
return 0;
if (utf8)
#ifdef WA_VALIDATE
printf(" Muxing App: %s\n", utf8);
segment_info.muxing_app_found = true;
#endif
segment_info.Own(segment_info.muxing_app, utf8);
}
break;
case mkv_segmentinfo_writingapp:
{
char *utf8 = 0;
if (node.size && read_utf8(reader, node.size, &utf8) == 0)
return 0;
if (utf8)
#ifdef WA_VALIDATE
printf(" Writing App: %s\n", utf8);
segment_info.writing_app_found = true;
#endif
segment_info.Own(segment_info.writing_app, utf8);
}
break;
case mkv_segmentinfo_duration:
{
double val;
if (read_float(reader, node.size, &val) == 0)
return 0;
#ifdef WA_VALIDATE
printf(" Duration: %g\n", val);
segment_info.duration_found = true;
#endif
segment_info.duration = val;
}
break;
case mkv_segmentinfo_dateutc:
{
uint64_t val;
if (read_unsigned(reader, node.size, &val) == 0)
return 0;
segment_info.production_date = val;
// value is in nanoseconds, relative to jan 01, 2001. ugh
__time64_t val_time = mkv_date_as_time_t(val);
#ifdef WA_VALIDATE
printf(" Date UTC: %s", _ctime64(&val_time));
segment_info.production_date_found = true;
#endif
}
break;
case mkv_segmentinfo_segmentuid:
{
#ifdef WA_VALIDATE
printf(" Segment UID: binary size %I64u\n", node.size);
segment_info.segment_uid_found = true;
#endif
if (node.size == 16)
{
size_t bytes_read;
reader->Read(&segment_info.segment_uid, (size_t)node.size, &bytes_read);
if (bytes_read != node.size)
return 0;
}
else // bad size, let's just skip it
{
reader->Skip(node.size);
}
}
break;
case mkv_segmentinfo_prevuid:
{
#ifdef WA_VALIDATE
printf(" Previous UID: binary size %I64u\n", node.size);
segment_info.prev_uid_found = true;
#endif
if (node.size == 16)
{
size_t bytes_read;
reader->Read(&segment_info.prev_uid, (size_t)node.size, &bytes_read);
if (bytes_read != node.size)
return 0;
}
else // bad size, let's just skip it
{
reader->Skip(node.size);
}
}
break;
case mkv_segmentinfo_nextuid:
{
#ifdef WA_VALIDATE
printf(" Next Segment UID: binary size %I64u\n", node.size);
segment_info.next_uid_found = true;
#endif
if (node.size == 16)
{
size_t bytes_read;
reader->Read(&segment_info.next_uid, (size_t)node.size, &bytes_read);
if (bytes_read != node.size)
return 0;
}
else // bad size, let's just skip it
{
reader->Skip(node.size);
}
}
break;
case mkv_segmentinfo_title:
{
char *utf8 = 0;
if (read_utf8(reader, node.size, &utf8) == 0)
return 0;
if (utf8)
#ifdef WA_VALIDATE
printf(" Title: %s\n", utf8);
segment_info.title_found = true;
#endif
segment_info.Own(segment_info.title, utf8);
}
break;
case mkv_segmentinfo_prevfilename:
{
char *utf8 = 0;
if (read_utf8(reader, node.size, &utf8) == 0)
return 0;
if (utf8)
#ifdef WA_VALIDATE
printf(" Previous Filename: %s\n", utf8);
segment_info.prev_filename_found = true;
if (FileExists(segment_info.prev_filename) != 0)
{
printf("****Specified previous filename not found");
}
#endif
segment_info.Own(segment_info.prev_filename,utf8);
}
break;
case mkv_segmentinfo_nextfilename:
{
char *utf8 = 0;
if (read_utf8(reader, node.size, &utf8) == 0)
return 0;
if (utf8)
#ifdef WA_VALIDATE
printf(" Next Filename: %s\n", utf8);
segment_info.next_filename_found = true;
if (FileExists(segment_info.next_filename) != 0)
{
printf("****Specified next filename not found");
}
#endif
segment_info.Own(segment_info.next_filename, utf8);
}
break;
default:
nsmkv::ReadGlobal(reader, node.id, node.size);
}
}
return total_bytes_read;
}
int nsmkv::SegmentInfo::GetDurationMilliseconds() const
{
double nanoseconds = (double)time_code_scale * duration;
double microseconds = nanoseconds / 1000.0;
double milliseconds = microseconds / 1000.0;
return (int)milliseconds;
}
uint64_t nsmkv::SegmentInfo::ConvertMillisecondsToTime(int milliseconds) const
{
double time_code = (double)milliseconds * 1000000.0 / (double)time_code_scale;
return (uint64_t)time_code;
}
int FileExists(const char * filename) {
int iStat;
struct _stat64 fileInfo;
// get the file attributes
return (iStat = _stat64(filename,&fileInfo));
}
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