cdb.c File Reference

functions to read from CDB database More...

#include <cdb.h>
#include <errno.h>
#include <stdint.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

Macros
#define	CDB_HASHSTART   5381

Functions
static uint32_t	cdb_hash (const char *buf, unsigned int len)
static uint32_t	cdb_unpack (const char *buf)
const char *	cdb_seekmm (int fd, const char *key, unsigned int len, char **mm, const struct stat *st)

Detailed Description

functions to read from CDB database

Function Documentation

const char* cdb_seekmm	(	int	fd,
		const char *	key,
		unsigned int	len,
		char **	mm,
		const struct stat *	st
	)

perform cdb search on the given file

Parameters

fd	file descriptor to search (will be closed)
key	key to search for
len	length of key
mm	base of mmapped address space
st	file information

Returns

cdb value belonging to that key

Return values

NULL	no key found in database or error

If the function returns NULL and errno is 0 everything worked fine but there is no entry for key in the file. On error errno is set.

The file is mmaped into memory, the result pointer will point inside that memory. The caller must munmap() the value returned in mm if the function does not return NULL. fd will be closed before the function returns.