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-rw-r--r--src/liblzma/check/crc32_tablegen.c117
1 files changed, 117 insertions, 0 deletions
diff --git a/src/liblzma/check/crc32_tablegen.c b/src/liblzma/check/crc32_tablegen.c
new file mode 100644
index 0000000..31a4d27
--- /dev/null
+++ b/src/liblzma/check/crc32_tablegen.c
@@ -0,0 +1,117 @@
+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file crc32_tablegen.c
+/// \brief Generate crc32_table_le.h and crc32_table_be.h
+///
+/// Compiling: gcc -std=c99 -o crc32_tablegen crc32_tablegen.c
+/// Add -DWORDS_BIGENDIAN to generate big endian table.
+/// Add -DLZ_HASH_TABLE to generate lz_encoder_hash_table.h (little endian).
+//
+// Author: Lasse Collin
+//
+// This file has been put into the public domain.
+// You can do whatever you want with this file.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include <stdio.h>
+#include "../../common/tuklib_integer.h"
+
+
+static uint32_t crc32_table[8][256];
+
+
+static void
+init_crc32_table(void)
+{
+ static const uint32_t poly32 = UINT32_C(0xEDB88320);
+
+ for (size_t s = 0; s < 8; ++s) {
+ for (size_t b = 0; b < 256; ++b) {
+ uint32_t r = s == 0 ? b : crc32_table[s - 1][b];
+
+ for (size_t i = 0; i < 8; ++i) {
+ if (r & 1)
+ r = (r >> 1) ^ poly32;
+ else
+ r >>= 1;
+ }
+
+ crc32_table[s][b] = r;
+ }
+ }
+
+#ifdef WORDS_BIGENDIAN
+ for (size_t s = 0; s < 8; ++s)
+ for (size_t b = 0; b < 256; ++b)
+ crc32_table[s][b] = bswap32(crc32_table[s][b]);
+#endif
+
+ return;
+}
+
+
+static void
+print_crc32_table(void)
+{
+ printf("/* This file has been automatically generated by "
+ "crc32_tablegen.c. */\n\n"
+ "const uint32_t lzma_crc32_table[8][256] = {\n\t{");
+
+ for (size_t s = 0; s < 8; ++s) {
+ for (size_t b = 0; b < 256; ++b) {
+ if ((b % 4) == 0)
+ printf("\n\t\t");
+
+ printf("0x%08" PRIX32, crc32_table[s][b]);
+
+ if (b != 255)
+ printf(",%s", (b+1) % 4 == 0 ? "" : " ");
+ }
+
+ if (s == 7)
+ printf("\n\t}\n};\n");
+ else
+ printf("\n\t}, {");
+ }
+
+ return;
+}
+
+
+static void
+print_lz_table(void)
+{
+ printf("/* This file has been automatically generated by "
+ "crc32_tablegen.c. */\n\n"
+ "const uint32_t lzma_lz_hash_table[256] = {");
+
+ for (size_t b = 0; b < 256; ++b) {
+ if ((b % 4) == 0)
+ printf("\n\t");
+
+ printf("0x%08" PRIX32, crc32_table[0][b]);
+
+ if (b != 255)
+ printf(",%s", (b+1) % 4 == 0 ? "" : " ");
+ }
+
+ printf("\n};\n");
+
+ return;
+}
+
+
+int
+main(void)
+{
+ init_crc32_table();
+
+#ifdef LZ_HASH_TABLE
+ print_lz_table();
+#else
+ print_crc32_table();
+#endif
+
+ return 0;
+}