diff --git a/MemoryModule.c b/MemoryModule.c index cf38388..59a5844 100644 --- a/MemoryModule.c +++ b/MemoryModule.c @@ -22,6 +22,12 @@ * Portions created by Joachim Bauch are Copyright (C) 2004-2015 * Joachim Bauch. All Rights Reserved. * + * + * THeller: Added binary search in MemoryGetProcAddress function + * (#define USE_BINARY_SEARCH to enable it). This gives a very large + * speedup for libraries that exports lots of functions. + * + * These portions are Copyright (C) 2013 Thomas Heller. */ #include @@ -56,6 +62,11 @@ #include "MemoryModule.h" +struct ExportNameEntry { + LPCSTR name; + WORD idx; +}; + typedef BOOL (WINAPI *DllEntryProc)(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpReserved); typedef int (WINAPI *ExeEntryProc)(void); @@ -72,6 +83,7 @@ typedef struct { CustomLoadLibraryFunc loadLibrary; CustomGetProcAddressFunc getProcAddress; CustomFreeLibraryFunc freeLibrary; + struct ExportNameEntry *nameExportsTable; void *userdata; ExeEntryProc exeEntry; DWORD pageSize; @@ -688,12 +700,27 @@ error: return NULL; } -FARPROC MemoryGetProcAddress(HMEMORYMODULE module, LPCSTR name) +static int _compare(const void *a, const void *b) { - unsigned char *codeBase = ((PMEMORYMODULE)module)->codeBase; + const struct ExportNameEntry *p1 = (const struct ExportNameEntry*) a; + const struct ExportNameEntry *p2 = (const struct ExportNameEntry*) b; + return _stricmp(p1->name, p2->name); +} + +static int _find(const void *a, const void *b) +{ + LPCSTR *name = (LPCSTR *) a; + const struct ExportNameEntry *p = (const struct ExportNameEntry*) b; + return _stricmp(*name, p->name); +} + +FARPROC MemoryGetProcAddress(HMEMORYMODULE mod, LPCSTR name) +{ + PMEMORYMODULE module = (PMEMORYMODULE)mod; + unsigned char *codeBase = module->codeBase; DWORD idx = 0; PIMAGE_EXPORT_DIRECTORY exports; - PIMAGE_DATA_DIRECTORY directory = GET_HEADER_DICTIONARY((PMEMORYMODULE)module, IMAGE_DIRECTORY_ENTRY_EXPORT); + PIMAGE_DATA_DIRECTORY directory = GET_HEADER_DICTIONARY(module, IMAGE_DIRECTORY_ENTRY_EXPORT); if (directory->Size == 0) { // no export table found SetLastError(ERROR_PROC_NOT_FOUND); @@ -715,25 +742,44 @@ FARPROC MemoryGetProcAddress(HMEMORYMODULE module, LPCSTR name) } idx = LOWORD(name) - exports->Base; + } else if (!exports->NumberOfNames) { + SetLastError(ERROR_PROC_NOT_FOUND); + return NULL; } else { - // search function name in list of exported names - DWORD i; - DWORD *nameRef = (DWORD *) (codeBase + exports->AddressOfNames); - WORD *ordinal = (WORD *) (codeBase + exports->AddressOfNameOrdinals); - BOOL found = FALSE; - for (i=0; iNumberOfNames; i++, nameRef++, ordinal++) { - if (_stricmp(name, (const char *) (codeBase + (*nameRef))) == 0) { - idx = *ordinal; - found = TRUE; - break; + const struct ExportNameEntry *found; + + // Lazily build name table and sort it by names + if (!module->nameExportsTable) { + DWORD i; + DWORD *nameRef = (DWORD *) (codeBase + exports->AddressOfNames); + WORD *ordinal = (WORD *) (codeBase + exports->AddressOfNameOrdinals); + struct ExportNameEntry *entry = (struct ExportNameEntry*) malloc(exports->NumberOfNames * sizeof(struct ExportNameEntry)); + module->nameExportsTable = entry; + if (!entry) { + SetLastError(ERROR_OUTOFMEMORY); + return NULL; } + for (i=0; iNumberOfNames; i++, nameRef++, ordinal++, entry++) { + entry->name = (const char *) (codeBase + (*nameRef)); + entry->idx = *ordinal; + } + qsort(module->nameExportsTable, + exports->NumberOfNames, + sizeof(struct ExportNameEntry), _compare); } + // search function name in list of exported names with binary search + found = (const struct ExportNameEntry*) bsearch(&name, + module->nameExportsTable, + exports->NumberOfNames, + sizeof(struct ExportNameEntry), _find); if (!found) { // exported symbol not found SetLastError(ERROR_PROC_NOT_FOUND); return NULL; } + + idx = found->idx; } if (idx > exports->NumberOfFunctions) { @@ -759,6 +805,7 @@ void MemoryFreeLibrary(HMEMORYMODULE mod) (*DllEntry)((HINSTANCE)module->codeBase, DLL_PROCESS_DETACH, 0); } + free(module->nameExportsTable); if (module->modules != NULL) { // free previously opened libraries int i;