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#include <sys/types.h>
#include <errno.h>
#include "cdb.h"
#ifndef SEEK_SET
#define SEEK_SET 0
#endif
int cdb_bread(fd,buf,len)
int fd;
char *buf;
int len;
{
int r;
while (len > 0) {
do
r = read(fd,buf,len);
while ((r == -1) && (errno == EINTR));
if (r == -1) return -1;
if (r == 0) { errno = EIO; return -1; }
buf += r;
len -= r;
}
return 0;
}
static int match(fd,key,len)
int fd;
char *key;
unsigned int len;
{
char buf[32];
int n;
int i;
while (len > 0) {
n = sizeof(buf);
if (n > len) n = len;
if (cdb_bread(fd,buf,n) == -1) return -1;
for (i = 0;i < n;++i) if (buf[i] != key[i]) return 0;
key += n;
len -= n;
}
return 1;
}
int cdb_seek(fd,key,len,dlen)
int fd;
char *key;
unsigned int len;
uint32 *dlen;
{
char packbuf[8];
uint32 pos;
uint32 h;
uint32 lenhash;
uint32 h2;
uint32 loop;
uint32 poskd;
h = cdb_hash(key,len);
pos = 8 * (h & 255);
if (lseek(fd,(off_t) pos,SEEK_SET) == -1) return -1;
if (cdb_bread(fd,packbuf,8) == -1) return -1;
pos = cdb_unpack(packbuf);
lenhash = cdb_unpack(packbuf + 4);
if (!lenhash) return 0;
h2 = (h >> 8) % lenhash;
for (loop = 0;loop < lenhash;++loop) {
if (lseek(fd,(off_t) (pos + 8 * h2),SEEK_SET) == -1) return -1;
if (cdb_bread(fd,packbuf,8) == -1) return -1;
poskd = cdb_unpack(packbuf + 4);
if (!poskd) return 0;
if (cdb_unpack(packbuf) == h) {
if (lseek(fd,(off_t) poskd,SEEK_SET) == -1) return -1;
if (cdb_bread(fd,packbuf,8) == -1) return -1;
if (cdb_unpack(packbuf) == len)
switch(match(fd,key,len)) {
case -1:
return -1;
case 1:
*dlen = cdb_unpack(packbuf + 4);
return 1;
}
}
if (++h2 == lenhash) h2 = 0;
}
return 0;
}
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