快速MD5计算

来源：互联网发布：linux终端删除～$ 编辑：程序博客网时间：2024/05/02 01:53

由Windows API实现的一个MD5计算函数，在Windows平台上比其他开源的MD5库快20%以上。

std::string CalcMD5(LPCVOID lpData, DWORD dwSize, BOOL bUpper){if(lpData == NULL || dwSize == 0)return "";std::string Str;HCRYPTPROV hProv = NULL;if(CryptAcquireContext(&hProv, NULL, NULL, PROV_RSA_AES, CRYPT_VERIFYCONTEXT)){HCRYPTHASH hHash = NULL;if(CryptCreateHash(hProv, CALG_MD5, NULL, 0, &hHash)){if(CryptHashData(hHash, (PBYTE)lpData, dwSize, 0)){DWORD dwLength = 16;PBYTE pMemory = (PBYTE)HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, dwLength);if(pMemory != NULL){if(CryptGetHashParam(hHash, HP_HASHVAL, pMemory, &dwLength, 0)){CHAR Temp[4] = {};for(DWORD i = 0; i < dwLength; ++i){sprintf_s(Temp, _countof(Temp), bUpper ? "%02X" : "%02x", pMemory[i]);Str.append(Temp);}}HeapFree(GetProcessHeap(), 0, pMemory);}}CryptDestroyHash(hHash);}CryptReleaseContext(hProv, 0);}return Str;}