LowLevel/Luma3DS-3GX
Archived
1
0
Fork 0
Code Issues Pull Requests Releases 2 Wiki Activity

memsearch() replaced with a Boyer-Moore Horspool implementation due to Quick Search being buggy in some rare cases

Browse Source
This commit is contained in:
Aurora 2016-09-11 16:22:13 +02:00
parent 7bd0e4f5b4
commit 66e0cfc185
3 changed files with 17 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
injector/source/memory.c
View File

@ -23,27 +23,26 @@ int memcmp(const void *buf1, const void *buf2, u32 size)
return 0; return 0;
} }
//Quick Search algorithm, adapted from http://igm.univ-mlv.fr/~lecroq/string/node19.html#SECTION00190 //Boyer-Moore Horspool algorithm, adapted from http://www-igm.univ-mlv.fr/~lecroq/string/node18.html#SECTION00180
u8 *memsearch(u8 *startPos, const void *pattern, u32 size, u32 patternSize) u8 *memsearch(u8 *startPos, const void *pattern, u32 size, u32 patternSize)
{ {
const u8 *patternc = (const u8 *)pattern; const u8 *patternc = (const u8 *)pattern;
//Preprocessing
u32 table[256]; u32 table[256];
//Preprocessing
for(u32 i = 0; i < 256; i++) for(u32 i = 0; i < 256; i++)
table[i] = patternSize + 1; table[i] = patternSize;
for(u32 i = 0; i < patternSize; i++) for(u32 i = 0; i < patternSize - 1; i++)
table[patternc[i]] = patternSize - i; table[patternc[i]] = patternSize - i - 1;
//Searching //Searching
u32 j = 0; u32 j = 0;
while(j <= size - patternSize) while(j <= size - patternSize)
{ {
if(memcmp(pattern, startPos + j, patternSize) == 0) u8 c = startPos[j + patternSize - 1];
if(patternc[patternSize - 1] == c && memcmp(pattern, startPos + j, patternSize - 1) == 0)
return startPos + j; return startPos + j;
j += table[startPos[j + patternSize]]; j += table[c];
} }
return NULL; return NULL;

17
source/memory.c
View File

@ -21,7 +21,7 @@
*/ */
/* /*
* Quick Search algorithm adapted from http://igm.univ-mlv.fr/~lecroq/string/node19.html#SECTION00190 * Boyer-Moore Horspool algorithm adapted from http://www-igm.univ-mlv.fr/~lecroq/string/node18.html#SECTION00180
* memcpy, memset32 and memcmp adapted from https://github.com/mid-kid/CakesForeveryWan/blob/557a8e8605ab3ee173af6497486e8f22c261d0e2/source/memfuncs.c * memcpy, memset32 and memcmp adapted from https://github.com/mid-kid/CakesForeveryWan/blob/557a8e8605ab3ee173af6497486e8f22c261d0e2/source/memfuncs.c
*/ */
@ -61,23 +61,22 @@ int memcmp(const void *buf1, const void *buf2, u32 size)
u8 *memsearch(u8 *startPos, const void *pattern, u32 size, u32 patternSize) u8 *memsearch(u8 *startPos, const void *pattern, u32 size, u32 patternSize)
{ {
const u8 *patternc = (const u8 *)pattern; const u8 *patternc = (const u8 *)pattern;
//Preprocessing
u32 table[256]; u32 table[256];
//Preprocessing
for(u32 i = 0; i < 256; i++) for(u32 i = 0; i < 256; i++)
table[i] = patternSize + 1; table[i] = patternSize;
for(u32 i = 0; i < patternSize; i++) for(u32 i = 0; i < patternSize - 1; i++)
table[patternc[i]] = patternSize - i; table[patternc[i]] = patternSize - i - 1;
//Searching //Searching
u32 j = 0; u32 j = 0;
while(j <= size - patternSize) while(j <= size - patternSize)
{ {
if(memcmp(pattern, startPos + j, patternSize) == 0) u8 c = startPos[j + patternSize - 1];
if(patternc[patternSize - 1] == c && memcmp(pattern, startPos + j, patternSize - 1) == 0)
return startPos + j; return startPos + j;
j += table[startPos[j + patternSize]]; j += table[c];
} }
return NULL; return NULL;

2
source/memory.h
View File

@ -21,7 +21,7 @@
*/ */
/* /*
* Quick Search algorithm adapted from http://igm.univ-mlv.fr/~lecroq/string/node19.html#SECTION00190 * Boyer-Moore Horspool algorithm adapted from http://www-igm.univ-mlv.fr/~lecroq/string/node18.html#SECTION00180
* memcpy, memset32 and memcmp adapted from https://github.com/mid-kid/CakesForeveryWan/blob/557a8e8605ab3ee173af6497486e8f22c261d0e2/source/memfuncs.c * memcpy, memset32 and memcmp adapted from https://github.com/mid-kid/CakesForeveryWan/blob/557a8e8605ab3ee173af6497486e8f22c261d0e2/source/memfuncs.c
*/ */