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

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Aurora 2016-09-11 16:22:13 +02:00
parent 7bd0e4f5b4
commit 66e0cfc185
3 changed files with 17 additions and 19 deletions
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17
injector/source/memory.c
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@ -23,27 +23,26 @@ int memcmp(const void *buf1, const void *buf2, u32 size)
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)
{
const u8 *patternc = (const u8 *)pattern;
//Preprocessing
u32 table[256];
//Preprocessing
for(u32 i = 0; i < 256; i++)
table[i] = patternSize + 1;
for(u32 i = 0; i < patternSize; i++)
table[patternc[i]] = patternSize - i;
table[i] = patternSize;
for(u32 i = 0; i < patternSize - 1; i++)
table[patternc[i]] = patternSize - i - 1;
//Searching
u32 j = 0;
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;
j += table[startPos[j + patternSize]];
j += table[c];
}
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
*/
@ -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)
{
const u8 *patternc = (const u8 *)pattern;
//Preprocessing
u32 table[256];
//Preprocessing
for(u32 i = 0; i < 256; i++)
table[i] = patternSize + 1;
for(u32 i = 0; i < patternSize; i++)
table[patternc[i]] = patternSize - i;
table[i] = patternSize;
for(u32 i = 0; i < patternSize - 1; i++)
table[patternc[i]] = patternSize - i - 1;
//Searching
u32 j = 0;
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;
j += table[startPos[j + patternSize]];
j += table[c];
}
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
*/