TLS (BO2) - Revision history

Therifboy at 22:26, 26 November 2014

2014-11-26T22:26:19Z

← Older revision		Revision as of 22:26, 26 November 2014
Line 1:		Line 1:
	[[Category:Game Structures]]		[[Category:Game Structures]]
	[[Category:BO2]]		[[Category:BO2]]
	TLS Stands for Thread Local Storage. It is a section of data that is unique to each thread and is being pointed to by the register r13 in the powerpc architecture. Some functions make use of that tls to access some buffers like va. Not setting up the tls like the game would do it will most likely cause a crash when calling functions that make use of that storage.		TLS Stands for Thread Local Storage. It is a section of data that is unique to each thread and is being pointed to by the register r13 in the powerpc architecture. Some functions make use of that tls to access some buffers like va Com_Error, etc... Not setting up the tls like the game would do it will most likely cause a crash when calling functions that make use of that storage.

	<syntaxhighlight lang="cpp">		<syntaxhighlight lang="cpp">
	struct ~~tls_data_t~~		struct TraceThreadInfo_t // not sure if the name is correct
	{		{
	~~int zero~~;		short unk0;
	short* partitions; ~~// used for traceWork_t::threadInfo.checkcount.partitions~~		short (*partitions)[0x1ED0];
	short* partitions2; ~~// used for traceWork_t::threadInfo.checkcount.partitions~~		short (*partitions2)[0x1ED0];
	char *ptr0;		char (*ptr0)[0x60];
	char *ptr1;		char (*ptr1)[0x4C];
	char *ptr2;		char (*ptr2)[0x4];
	};		};

Line 39:		Line 39:
	va_info_t* va;		va_info_t* va;
	jmp_buf* env; // located in the header <setjmp.h>		jmp_buf* env; // located in the header <setjmp.h>
	~~tls_data_t~~* data;		TraceThreadInfo_t* data;
	CmdArgs* integers;		CmdArgs* integers;
	};		};
Line 60:		Line 60:
	char* buffer = info->va_string[index];		char* buffer = info->va_string[index];
	int ret = vsnprintf(buffer, 0x400, fmt, args);		int ret = vsnprintf(buffer, 0x400, fmt, args);
			va_end(args);
	if (ret < 0 \|\| ret >= 0x400)		if (ret < 0 \|\| ret >= 0x400)
	{		{
Line 65:		Line 66:
	Com_Error(ERR_DROP, "\x15Attempted to overrun string in call to va(): '%s'", buffer);		Com_Error(ERR_DROP, "\x15Attempted to overrun string in call to va(): '%s'", buffer);
	}		}
	~~va_end(args);~~
	return buffer;		return buffer;
	}		}
	</syntaxhighlight>		</syntaxhighlight>

Therifboy at 11:28, 25 November 2014

2014-11-25T11:28:09Z

← Older revision		Revision as of 11:28, 25 November 2014
Line 65:		Line 65:
	Com_Error(ERR_DROP, "\x15Attempted to overrun string in call to va(): '%s'", buffer);		Com_Error(ERR_DROP, "\x15Attempted to overrun string in call to va(): '%s'", buffer);
	}		}
			va_end(args);
	return buffer;		return buffer;
	}		}
	</syntaxhighlight>		</syntaxhighlight>

Therifboy: Created page with "Category:Game Structures Category:BO2 TLS Stands for Thread Local Storage. It is a section of data that is unique to each thread and is being pointed to by the registe..."

2014-11-25T10:23:12Z

Created page with "Category:Game Structures Category:BO2 TLS Stands for Thread Local Storage. It is a section of data that is unique to each thread and is being pointed to by the registe..."

New page

[[Category:Game Structures]]
[[Category:BO2]]
TLS Stands for Thread Local Storage. It is a section of data that is unique to each thread and is being pointed to by the register r13 in the powerpc architecture. Some functions make use of that tls to access some buffers like va. Not setting up the tls like the game would do it will most likely cause a crash when calling functions that make use of that storage.

<syntaxhighlight lang="cpp">
struct tls_data_t
{
int zero;
short* partitions; // used for traceWork_t::threadInfo.checkcount.partitions
short* partitions2; // used for traceWork_t::threadInfo.checkcount.partitions
char *ptr0;
char *ptr1;
char *ptr2;
};

struct va_info_t
{
char va_string[4][0x400];
int index;
};

struct CmdArgs
{
int nesting; //0x0
char unk0[0x60]; //0x4
int localClientNum[8]; //0x64
int argc[8]; //0x84
const char **argv[8]; //0xA4
char textPool[0x2000]; //0xC4
const char* argvPool[0x200]; //0x20C4
int usedTextPool[8]; //0x28C4
int totalUsedArgvPool; //0x28E4
int totalUsedTextPool;//0x28E8
};

struct tls_t
{
int zero;
va_info_t* va;
jmp_buf* env; // located in the header <setjmp.h>
tls_data_t* data;
CmdArgs* integers;
};
</syntaxhighlight>

To access that storage, Sys_GetValue and Sys_SetValue are used.
<syntaxhighlight lang="cpp">
void* Sys_GetValue(int index);
void Sys_SetValue(int index, void* value);
</syntaxhighlight>

An example of how that buffer is accessed:
<syntaxhighlight lang="cpp">
char* va(const char* fmt, ...)
{
va_list args;
va_start(args, fmt);
va_info_t* info = (va_info_t*)Sys_GetValue(1);
int index = info->index++;
char* buffer = info->va_string[index];
int ret = vsnprintf(buffer, 0x400, fmt, args);
if (ret < 0 || ret >= 0x400)
{
buffer[0x3FF] = '\0';
Com_Error(ERR_DROP, "\x15Attempted to overrun string in call to va(): '%s'", buffer);
}
return buffer;
}
</syntaxhighlight>