Merge commit 'dec0d4ec4153bf9fc2b78ae6c2df45b6ea8dde7a' as 'external/sdl/SDL'

external/sdl/SDL/src/test/SDL_test_crc32.c

@@ -0,0 +1,160 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2023 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+/*
+
+ Used by the test execution component.
+ Original source code contributed by A. Schiffler for GSOC project.
+
+*/
+#include <SDL3/SDL_test.h>
+
+int SDLTest_Crc32Init(SDLTest_Crc32Context *crcContext)
+{
+    int i, j;
+    CrcUint32 c;
+
+    /* Sanity check context pointer */
+    if (crcContext == NULL) {
+        return -1;
+    }
+
+    /*
+     * Build auxiliary table for parallel byte-at-a-time CRC-32
+     */
+#ifdef ORIGINAL_METHOD
+    for (i = 0; i < 256; ++i) {
+        for (c = i << 24, j = 8; j > 0; --j) {
+            c = c & 0x80000000 ? (c << 1) ^ CRC32_POLY : (c << 1);
+        }
+        crcContext->crc32_table[i] = c;
+    }
+#else
+    for (i = 0; i < 256; i++) {
+        c = i;
+        for (j = 8; j > 0; j--) {
+            if (c & 1) {
+                c = (c >> 1) ^ CRC32_POLY;
+            } else {
+                c >>= 1;
+            }
+        }
+        crcContext->crc32_table[i] = c;
+    }
+#endif
+
+    return 0;
+}
+
+/* Complete CRC32 calculation on a memory block */
+int SDLTest_Crc32Calc(SDLTest_Crc32Context *crcContext, CrcUint8 *inBuf, CrcUint32 inLen, CrcUint32 *crc32)
+{
+    if (SDLTest_Crc32CalcStart(crcContext, crc32)) {
+        return -1;
+    }
+
+    if (SDLTest_Crc32CalcBuffer(crcContext, inBuf, inLen, crc32)) {
+        return -1;
+    }
+
+    if (SDLTest_Crc32CalcEnd(crcContext, crc32)) {
+        return -1;
+    }
+
+    return 0;
+}
+
+/* Start crc calculation */
+
+int SDLTest_Crc32CalcStart(SDLTest_Crc32Context *crcContext, CrcUint32 *crc32)
+{
+    /* Sanity check pointers */
+    if (crcContext == NULL) {
+        *crc32 = 0;
+        return -1;
+    }
+
+    /*
+     * Preload shift register, per CRC-32 spec
+     */
+    *crc32 = 0xffffffff;
+
+    return 0;
+}
+
+/* Finish crc calculation */
+
+int SDLTest_Crc32CalcEnd(SDLTest_Crc32Context *crcContext, CrcUint32 *crc32)
+{
+    /* Sanity check pointers */
+    if (crcContext == NULL) {
+        *crc32 = 0;
+        return -1;
+    }
+
+    /*
+     * Return complement, per CRC-32 spec
+     */
+    *crc32 = (~(*crc32));
+
+    return 0;
+}
+
+/* Include memory block in crc */
+
+int SDLTest_Crc32CalcBuffer(SDLTest_Crc32Context *crcContext, CrcUint8 *inBuf, CrcUint32 inLen, CrcUint32 *crc32)
+{
+    CrcUint8 *p;
+    register CrcUint32 crc;
+
+    if (crcContext == NULL) {
+        *crc32 = 0;
+        return -1;
+    }
+
+    if (inBuf == NULL) {
+        return -1;
+    }
+
+    /*
+     * Calculate CRC from data
+     */
+    crc = *crc32;
+    for (p = inBuf; inLen > 0; ++p, --inLen) {
+#ifdef ORIGINAL_METHOD
+        crc = (crc << 8) ^ crcContext->crc32_table[(crc >> 24) ^ *p];
+#else
+        crc = ((crc >> 8) & 0x00FFFFFF) ^ crcContext->crc32_table[(crc ^ *p) & 0xFF];
+#endif
+    }
+    *crc32 = crc;
+
+    return 0;
+}
+
+int SDLTest_Crc32Done(SDLTest_Crc32Context *crcContext)
+{
+    if (crcContext == NULL) {
+        return -1;
+    }
+
+    return 0;
+}