src/utilfuns/zlib/crc32.c File Reference

#include "zlib.h"

Include dependency graph for crc32.c:

Go to the source code of this file.

Defines
#define	DO1(buf)   crc = crc_table[((int)crc ^ (*buf++)) & 0xff] ^ (crc >> 8);
#define	DO2(buf)   DO1(buf); DO1(buf);
#define	DO4(buf)   DO2(buf); DO2(buf);
#define	DO8(buf)   DO4(buf); DO4(buf);
#define	local   static
Functions
uLong ZEXPORT	crc32 (uLong crc, const Bytef *buf, uInt len)
const uLongf *ZEXPORT	get_crc_table ()
Variables
local const uLongf	crc_table [256]

---

Define Documentation

#define DO1

(

buf

)

crc = crc_table[((int)crc ^ (*buf++)) & 0xff] ^ (crc >> 8);

Definition at line 136 of file crc32.c.

#define DO2

(

buf

)

DO1(buf); DO1(buf);

Definition at line 137 of file crc32.c.

#define DO4

(

buf

)

DO2(buf); DO2(buf);

Definition at line 138 of file crc32.c.

#define DO8

(

buf

)

DO4(buf); DO4(buf);

Definition at line 139 of file crc32.c.

#define local   static

Definition at line 10 of file crc32.c.

---

Function Documentation

uLong ZEXPORT crc32	(	uLong	crc,
		const Bytef *	buf,
		uInt	len
	)

Definition at line 142 of file crc32.c.

{
    if (buf == Z_NULL) return 0L;
#ifdef DYNAMIC_CRC_TABLE
    if (crc_table_empty)
      make_crc_table();
#endif
    crc = crc ^ 0xffffffffL;
    while (len >= 8)
    {
      DO8(buf);
      len -= 8;
    }
    if (len) do {
      DO1(buf);
    } while (--len);
    return crc ^ 0xffffffffL;
}

const uLongf* ZEXPORT get_crc_table

(

)

Definition at line 127 of file crc32.c.

{
#ifdef DYNAMIC_CRC_TABLE
  if (crc_table_empty) make_crc_table();
#endif
  return (const uLongf *)crc_table;
}

---

Variable Documentation

local const uLongf crc_table[256]

Definition at line 68 of file crc32.c.