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Diffstat (limited to 'source/3rd-party/SDL2/src/test/SDL_test_crc32.c')
-rw-r--r--source/3rd-party/SDL2/src/test/SDL_test_crc32.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/source/3rd-party/SDL2/src/test/SDL_test_crc32.c b/source/3rd-party/SDL2/src/test/SDL_test_crc32.c
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index 0000000..ea6b0a8
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+++ b/source/3rd-party/SDL2/src/test/SDL_test_crc32.c
@@ -0,0 +1,166 @@
+/*
+ Simple DirectMedia Layer
+ Copyright (C) 1997-2018 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 "SDL_config.h"
+
+#include "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;
+}
+
+/* vi: set ts=4 sw=4 expandtab: */