ash: exec: Stricter pathopt parsing

[oweals/busybox.git] / libbb / crc32.c

diff --git a/libbb/crc32.c b/libbb/crc32.c
index acbc4582756763ee621326e8ed53d47f8091acd9..728bcb73610c47505bb3e17c2458c1976e9922b0 100644 (file)
--- a/libbb/crc32.c
+++ b/libbb/crc32.c
@@ -12,15 +12,18 @@
  *
  * endian = 1: big-endian
  * endian = 0: little-endian
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
  */
-
 #include "libbb.h"
 
-uint32_t *crc32_filltable(uint32_t *crc_table, int endian)
+uint32_t *global_crc32_table;
+
+uint32_t* FAST_FUNC crc32_filltable(uint32_t *crc_table, int endian)
 {
        uint32_t polynomial = endian ? 0x04c11db7 : 0xedb88320;
        uint32_t c;
-       int i, j;
+       unsigned i, j;
 
        if (!crc_table)
                crc_table = xmalloc(256 * sizeof(uint32_t));
@@ -38,3 +41,35 @@ uint32_t *crc32_filltable(uint32_t *crc_table, int endian)
 
        return crc_table - 256;
 }
+/* Common uses: */
+uint32_t* FAST_FUNC crc32_new_table_le(void)
+{
+       return crc32_filltable(NULL, 0);
+}
+uint32_t* FAST_FUNC global_crc32_new_table_le(void)
+{
+       global_crc32_table = crc32_new_table_le();
+       return global_crc32_table;
+}
+
+uint32_t FAST_FUNC crc32_block_endian1(uint32_t val, const void *buf, unsigned len, uint32_t *crc_table)
+{
+       const void *end = (uint8_t*)buf + len;
+
+       while (buf != end) {
+               val = (val << 8) ^ crc_table[(val >> 24) ^ *(uint8_t*)buf];
+               buf = (uint8_t*)buf + 1;
+       }
+       return val;
+}
+
+uint32_t FAST_FUNC crc32_block_endian0(uint32_t val, const void *buf, unsigned len, uint32_t *crc_table)
+{
+       const void *end = (uint8_t*)buf + len;
+
+       while (buf != end) {
+               val = crc_table[(uint8_t)val ^ *(uint8_t*)buf] ^ (val >> 8);
+               buf = (uint8_t*)buf + 1;
+       }
+       return val;
+}