ADDED: Utility functions: `ComputeCRC32()` and `ComputeMD5()`

src/raylib.h

@@ -1144,6 +1144,8 @@ RLAPI unsigned char *CompressData(const unsigned char *data, int dataSize, int *
 RLAPI unsigned char *DecompressData(const unsigned char *compData, int compDataSize, int *dataSize);  // Decompress data (DEFLATE algorithm), memory must be MemFree()
 RLAPI char *EncodeDataBase64(const unsigned char *data, int dataSize, int *outputSize);               // Encode data to Base64 string, memory must be MemFree()
 RLAPI unsigned char *DecodeDataBase64(const unsigned char *data, int *outputSize);                    // Decode Base64 string data, memory must be MemFree()
+RLAPI unsigned int ComputeCRC32(unsigned char *data, int dataSize);     // Compute CRC32 hash code
+RLAPI unsigned int *ComputeMD5(unsigned char *data, int dataSize);      // Compute MD5 hash code, returns static int[4] (16 bytes)
 
 // Automation events functionality
 RLAPI AutomationEventList LoadAutomationEventList(const char *fileName);                // Load automation events list from file, NULL for empty list, capacity = MAX_AUTOMATION_EVENTS

src/rcore.c

@@ -2577,6 +2577,169 @@ unsigned char *DecodeDataBase64(const unsigned char *data, int *outputSize)
     return decodedData;
 }
 
+// Compute CRC32 hash code
+unsigned int ComputeCRC32(unsigned char *data, int dataSize)
+{
+    static unsigned int crcTable[256] = {
+        0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3,
+        0x0eDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91,
+        0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7,
+        0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5,
+        0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B,
+        0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59,
+        0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F,
+        0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D,
+        0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,
+        0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01,
+        0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457,
+        0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,
+        0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB,
+        0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9,
+        0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
+        0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD,
+        0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683,
+        0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,
+        0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7,
+        0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5,
+        0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,
+        0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79,
+        0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F,
+        0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,
+        0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713,
+        0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21,
+        0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,
+        0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45,
+        0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB,
+        0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
+        0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF,
+        0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D
+    };
+
+    unsigned int crc = ~0u;
+
+    for (int i = 0; i < dataSize; i++) crc = (crc >> 8) ^ crcTable[data[i] ^ (crc & 0xff)];
+
+    return ~crc;
+}
+
+// Compute MD5 hash code
+// NOTE: Returns a static int[4] array (16 bytes)
+unsigned int *ComputeMD5(unsigned char *data, int dataSize)
+{
+    #define ROTATE_LEFT(x, c) (((x) << (c)) | ((x) >> (32 - (c))))
+
+    static unsigned int hash[4] = { 0 };  // Hash to be returned
+
+    // WARNING: All variables are unsigned 32 bit and wrap modulo 2^32 when calculating
+
+    // NOTE: r specifies the per-round shift amounts
+    unsigned int r[] = {
+        7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22,
+        5,  9, 14, 20, 5,  9, 14, 20, 5,  9, 14, 20, 5,  9, 14, 20,
+        4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23,
+        6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21
+    };
+
+    // Using binary integer part of the sines of integers (in radians) as constants
+    unsigned int k[] = {
+        0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,
+        0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
+        0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
+        0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
+        0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,
+        0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
+        0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
+        0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
+        0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,
+        0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
+        0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05,
+        0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
+        0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039,
+        0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
+        0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
+        0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391
+    };
+
+    hash[0] = 0x67452301;
+    hash[1] = 0xefcdab89;
+    hash[2] = 0x98badcfe;
+    hash[3] = 0x10325476;
+
+    // Pre-processing: adding a single 1 bit
+    // Append '1' bit to message
+    // NOTE: The input bytes are considered as bits strings,
+    // where the first bit is the most significant bit of the byte
+
+    // Pre-processing: padding with zeros
+    // Append '0' bit until message length in bit 448 (mod 512)
+    // Append length mod (2 pow 64) to message
+
+    int newDataSize = ((((dataSize + 8)/64) + 1)*64) - 8;
+
+    unsigned char *msg = RL_CALLOC(newDataSize + 64, 1); // Initialize with '0' bits, allocating 64 extra bytes
+    memcpy(msg, data, dataSize);
+    msg[dataSize] = 128; // Write the '1' bit
+
+    unsigned int bitsLen = 8*dataSize;
+    memcpy(msg + newDataSize, &bitsLen, 4); // Append the len in bits at the end of the buffer
+
+    // Process the message in successive 512-bit chunks for each 512-bit chunk of message
+    for (int offset = 0; offset < newDataSize; offset += (512/8))
+    {
+        // Break chunk into sixteen 32-bit words w[j], 0 <= j <= 15
+        unsigned int *w = (unsigned int *)(msg + offset);
+
+        // Initialize hash value for this chunk
+        unsigned int a = hash[0];
+        unsigned int b = hash[1];
+        unsigned int c = hash[2];
+        unsigned int d = hash[3];
+
+        for (int i = 0; i < 64; i++)
+        {
+            unsigned int f = 0;
+            unsigned int g = 0;
+
+            if (i < 16)
+            {
+                f = (b & c) | ((~b) & d);
+                g = i;
+            }
+            else if (i < 32)
+            {
+                f = (d & b) | ((~d) & c);
+                g = (5*i + 1)%16;
+            }
+            else if (i < 48)
+            {
+                f = b ^ c ^ d;
+                g = (3*i + 5)%16;
+            }
+            else
+            {
+                f = c ^ (b | (~d));
+                g = (7*i)%16;
+            }
+
+            unsigned int temp = d;
+            d = c;
+            c = b;
+            b = b + ROTATE_LEFT((a + f + k[i] + w[g]), r[i]);
+            a = temp;
+        }
+
+        // Add chunk's hash to result so far
+        hash[0] += a;
+        hash[1] += b;
+        hash[2] += c;
+        hash[3] += d;
+    }
+
+    RL_FREE(msg);
+
+    return hash;
+}
+
 //----------------------------------------------------------------------------------
 // Module Functions Definition: Automation Events Recording and Playing
 //----------------------------------------------------------------------------------