Changeset 4795:cf3e4ecde1f5 in roaraudio for libroar/crc.c

Timestamp:

03/14/11 15:47:34 (13 years ago)

Author:

phi

Branch:

default

Phase:

public

Message:

Added Adler32 support (Closes: #123) (pr1)

File:

• libroar/crc.c (modified) (3 diffs)

libroar/crc.c

@@ -39 +39 @@
 #define CRC24_INIT 0x00B704CEL
 
+#define ADLER32_BASE 65521L
+#define ADLER32_INIT 1L
+
 uint32_t roar_crc24_add(uint32_t state, const void * data, size_t len) {
  const unsigned char * p = data;
@@ -57 +60 @@
  return state & 0x00FFFFFFL;
 }
+
+uint32_t roar_adler32_add(uint32_t state, const void * data, size_t len) {
+ const unsigned char * p = data;
+ uint32_t s1 =  state        & 0xFFFFL;
+ uint32_t s2 = (state >> 16) & 0xFFFFL;
+ size_t n;
+
+ if ( data == NULL )
+  return ADLER32_INIT;
+
+ for (n = 0; n < len; n++) {
+  s1 = (s1 + p[n]) % ADLER32_BASE;
+  s2 = (s2 + s1  ) % ADLER32_BASE;
+ }
+
+ return (s2 << 16) + s1;
+}
+
 
 int roar_hash_crc24_init(void * state) {
@@ -93 +114 @@
 }
 
+
+int roar_hash_adler32_init(void * state) {
+ uint32_t * self = state;
+
+ *self = roar_adler32_init();
+
+ return 0;
+}
+
+int roar_hash_adler32_digest(void * state, void * digest, size_t * len) {
+ uint32_t * self = state;
+ unsigned char * out  = digest;
+ register uint32_t crc;
+
+ if ( *len < 4 )
+  return -1;
+
+ *len = 4;
+
+ crc = *self;
+
+ out[0] = ((crc & 0xFF000000) >> 24) & 0xFF;
+ out[1] = ((crc & 0x00FF0000) >> 16) & 0xFF;
+ out[2] = ((crc & 0x0000FF00) >>  8) & 0xFF;
+ out[3] = ((crc & 0x000000FF) >>  0) & 0xFF;
+
+ return 0;
+}
+
+int roar_hash_adler32_proc(void * state, const void * data, size_t len) {
+ uint32_t * self = state;
+
+ *self = roar_adler32_add(*self, data, len);
+
+ return 0;
+}
+
 //ll