Browse Source

add cdb

master
Felix von Leitner 16 years ago
parent
commit
03806dc0c8
  1. 1
      CHANGES
  2. 10
      GNUmakefile
  3. 11
      Makefile
  4. 37
      cdb.h
  5. 128
      cdb/cdb.c
  6. 17
      cdb/cdb_datalen.3
  7. 17
      cdb/cdb_datapos.3
  8. 42
      cdb/cdb_find.3
  9. 19
      cdb/cdb_firstkey.3
  10. 17
      cdb/cdb_free.3
  11. 19
      cdb/cdb_hash.c
  12. 20
      cdb/cdb_init.3
  13. 16
      cdb/cdb_keylen.3
  14. 16
      cdb/cdb_keypos.3
  15. 148
      cdb/cdb_make.c
  16. 19
      cdb/cdb_nextkey.3
  17. 20
      cdb/cdb_read.3
  18. 21
      cdb/cdb_successor.3
  19. 40
      cdb/cdb_traverse.c
  20. 39
      cdb_make.h

1
CHANGES

@ -9,6 +9,7 @@
that.
implement Nikola's idea to remove limit number of strings in errmsg
add taia_half
add cdb
0.24:
fix scan_to_sa (Tim Lorenz)

10
GNUmakefile

@ -10,7 +10,8 @@ INCLUDEDIR=${prefix}/include
MAN3DIR=${prefix}/man/man3
LIBS=byte.a fmt.a scan.a str.a uint.a open.a stralloc.a unix.a socket.a \
buffer.a mmap.a taia.a tai.a dns.a case.a mult.a array.a io.a textcode.a
buffer.a mmap.a taia.a tai.a dns.a case.a mult.a array.a io.a \
textcode.a cdb.a
all: t $(LIBS) libowfat.a libsocket
@ -53,7 +54,7 @@ endif
# to build without diet libc support, use $ make DIET=
# see http://www.fefe.de/dietlibc/ for details about the diet libc
VPATH=str:byte:fmt:scan:uint:open:stralloc:unix:socket:buffer:mmap:textcode:taia:tai:dns:case:array:mult:io
VPATH=str:byte:fmt:scan:uint:open:stralloc:unix:socket:buffer:mmap:textcode:taia:tai:dns:case:array:mult:io:cdb
BYTE_OBJS=$(patsubst byte/%.c,%.o,$(wildcard byte/*.c))
FMT_OBJS=$(patsubst fmt/%.c,%.o,$(wildcard fmt/*.c))
@ -74,6 +75,7 @@ CASE_OBJS=$(patsubst case/%.c,%.o,$(wildcard case/*.c))
ARRAY_OBJS=$(patsubst array/%.c,%.o,$(wildcard array/*.c))
MULT_OBJS=$(patsubst mult/%.c,%.o,$(wildcard mult/*.c))
IO_OBJS=$(patsubst io/%.c,%.o,$(wildcard io/*.c))
CDB_OBJS=$(patsubst cdb/%.c,%.o,$(wildcard cdb/*.c))
$(BYTE_OBJS): byte.h
$(FMT_OBJS): fmt.h
@ -92,6 +94,7 @@ $(CASE_OBJS): case.h
$(ARRAY_OBJS): uint64.h array.h
$(MULT_OBJS): uint64.h uint32.h uint16.h safemult.h
$(IO_OBJS): uint64.h array.h io.h io_internal.h taia.h tai.h haveepoll.h havekqueue.h havesigio.h havebsdsf.h havedevpoll.h havesendfile.h
$(CDB_OBJS): cdb.h uint32.h
iob_addbuf.o iob_addfile.o iob_new.o iob_reset.o iob_send.o: iob_internal.h iob.h
@ -120,6 +123,7 @@ case.a: $(CASE_OBJS)
array.a: $(ARRAY_OBJS)
mult.a: $(MULT_OBJS)
io.a: $(IO_OBJS)
cdb.a: $(CDB_OBJS)
ALL_OBJS=$(DNS_OBJS) $(BYTE_OBJS) $(FMT_OBJS) $(SCAN_OBJS) \
$(STR_OBJS) $(UINT_OBJS) $(OPEN_OBJS) $(STRALLOC_OBJS) $(UNIX_OBJS) \
@ -155,7 +159,7 @@ dep libsocket havealloca.h
INCLUDES=buffer.h byte.h fmt.h ip4.h ip6.h mmap.h scan.h socket.h str.h stralloc.h \
uint16.h uint32.h uint64.h open.h textcode.h tai.h taia.h dns.h iopause.h case.h \
openreadclose.h readclose.h ndelay.h array.h io.h safemult.h iob.h havealloca.h \
errmsg.h
errmsg.h cdb.h
install: libowfat.a
install -d $(INCLUDEDIR) $(MAN3DIR) $(LIBDIR)

11
Makefile

@ -11,7 +11,8 @@ INCLUDEDIR=${prefix}/include
MAN3DIR=${prefix}/man/man3
LIBS=byte.a fmt.a scan.a str.a uint.a open.a stralloc.a unix.a socket.a \
buffer.a mmap.a taia.a tai.a dns.a case.a mult.a array.a io.a textcode.a
buffer.a mmap.a taia.a tai.a dns.a case.a mult.a array.a io.a \
textcode.a cdb.a
all: t $(LIBS) libowfat.a libsocket
@ -116,6 +117,10 @@ case_diffs.o: case/case_diffs.c case.h
case_lowerb.o: case/case_lowerb.c case.h
case_lowers.o: case/case_lowers.c case.h
case_starts.o: case/case_starts.c case.h
cdb.o: cdb/cdb.c byte.h cdb.h uint32.h
cdb_hash.o: cdb/cdb_hash.c cdb.h uint32.h
cdb_make.o: cdb/cdb_make.c cdb.h uint32.h cdb_make.h buffer.h
cdb_traverse.o: cdb/cdb_traverse.c cdb.h uint32.h
dns_dfd.o: dns/dns_dfd.c byte.h dns.h stralloc.h iopause.h taia.h tai.h \
uint64.h
dns_domain.o: dns/dns_domain.c case.h byte.h dns.h stralloc.h iopause.h \
@ -523,6 +528,7 @@ MULT_OBJS=imult16.o imult32.o imult64.o umult16.o umult32.o umult64.o
ARRAY_OBJS=array_allocate.o array_bytes.o array_cat.o array_cat0.o array_catb.o array_cate.o array_cats.o array_cats0.o array_equal.o array_fail.o array_get.o array_length.o array_reset.o array_start.o array_trunc.o array_truncate.o
IO_OBJS=io_appendfile.o io_canread.o io_canwrite.o io_check.o io_close.o io_closeonexec.o io_createfile.o io_dontwantread.o io_dontwantwrite.o io_eagain.o io_fd.o io_finishandshutdown.o io_getcookie.o io_mmapwritefile.o io_nonblock.o io_passfd.o io_pipe.o io_readfile.o io_readwritefile.o io_receivefd.o io_sendfile.o io_setcookie.o io_sigpipe.o io_socketpair.o io_timeout.o io_timeouted.o io_tryread.o io_tryreadtimeout.o io_trywrite.o io_trywritetimeout.o io_wait.o io_waitread.o io_waituntil.o io_waituntil2.o io_waitwrite.o io_wantread.o io_wantwrite.o iob_addbuf.o iob_addbuf_free.o iob_addbuf_internal.o iob_addfile.o iob_addfile_close.o iob_adds.o iob_adds_free.o iob_free.o iob_new.o iob_prefetch.o iob_reset.o iob_send.o iob_write.o
TEXTCODE_OBJS=base64.o fmt_base64.o fmt_cescape.o fmt_foldwhitespace.o fmt_hexdump.o fmt_html.o fmt_quotedprintable.o fmt_to_array.o fmt_to_sa.o fmt_tofrom_array.o fmt_urlencoded.o fmt_uuencoded.o fmt_yenc.o scan_base64.o scan_cescape.o scan_hexdump.o scan_html.o scan_quotedprintable.o scan_to_array.o scan_to_sa.o scan_tofrom_array.o scan_urlencoded.o scan_uuencoded.o scan_yenc.o
CDB_OBJS=cdb.o cdb_hash.o cdb_make.o cdb_traverse.o
byte.a: $(BYTE_OBJS)
fmt.a: $(FMT_OBJS)
@ -543,6 +549,7 @@ case.a: $(CASE_OBJS)
array.a: $(ARRAY_OBJS)
mult.a: $(MULT_OBJS)
io.a: $(IO_OBJS)
cdb.a: $(CDB_OBJS)
ALL_OBJS=$(DNS_OBJS) $(BYTE_OBJS) $(FMT_OBJS) $(SCAN_OBJS) \
$(STR_OBJS) $(UINT_OBJS) $(OPEN_OBJS) $(STRALLOC_OBJS) $(UNIX_OBJS) \
@ -578,7 +585,7 @@ dep libsocket havealloca.h
INCLUDES=buffer.h byte.h fmt.h ip4.h ip6.h mmap.h scan.h socket.h str.h stralloc.h \
uint16.h uint32.h uint64.h open.h textcode.h tai.h taia.h dns.h iopause.h case.h \
openreadclose.h readclose.h ndelay.h array.h io.h safemult.h iob.h havealloca.h \
errmsg.h
errmsg.h cdb.h
install: libowfat.a
install -d $(INCLUDEDIR) $(MAN3DIR) $(LIBDIR)

37
cdb.h

@ -0,0 +1,37 @@
/* Public domain. */
#ifndef CDB_H
#define CDB_H
#include "uint32.h"
#define CDB_HASHSTART 5381
extern uint32 cdb_hashadd(uint32 h,unsigned char c);
extern uint32 cdb_hash(const unsigned char *buf,unsigned long int len);
struct cdb {
char *map; /* 0 if no map is available */
int fd;
uint32 size; /* initialized if map is nonzero */
uint32 loop; /* number of hash slots searched under this key */
uint32 khash; /* initialized if loop is nonzero */
uint32 kpos; /* initialized if loop is nonzero */
uint32 hpos; /* initialized if loop is nonzero */
uint32 hslots; /* initialized if loop is nonzero */
uint32 dpos; /* initialized if cdb_findnext() returns 1 */
uint32 dlen; /* initialized if cdb_findnext() returns 1 */
} ;
extern void cdb_free(struct cdb *);
extern void cdb_init(struct cdb *,int fd);
extern int cdb_read(struct cdb *,unsigned char *,unsigned long int,uint32);
extern void cdb_findstart(struct cdb *);
extern int cdb_findnext(struct cdb *,const unsigned char *,unsigned long int);
extern int cdb_find(struct cdb *,const unsigned char *,unsigned long int);
#define cdb_datapos(c) ((c)->dpos)
#define cdb_datalen(c) ((c)->dlen)
#endif

128
cdb/cdb.c

@ -0,0 +1,128 @@
#define _FILE_OFFSET_BITS 64
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <unistd.h>
#include <errno.h>
#include "byte.h"
#include "cdb.h"
void cdb_free(struct cdb *c) {
if (c->map) {
munmap(c->map,c->size);
c->map = 0;
}
}
void cdb_findstart(struct cdb *c) {
c->loop = 0;
}
void cdb_init(struct cdb *c,int fd) {
struct stat st;
char *x;
cdb_free(c);
cdb_findstart(c);
c->fd = fd;
if (fstat(fd,&st) == 0)
if (st.st_size <= 0xffffffff) {
x = mmap(0,st.st_size,PROT_READ,MAP_SHARED,fd,0);
if (x + 1) {
c->size = st.st_size;
c->map = x;
}
}
}
int cdb_read(struct cdb *c,unsigned char *buf,unsigned long len,uint32 pos) {
if (c->map) {
if ((pos > c->size) || (c->size - pos < len)) goto FORMAT;
byte_copy(buf,len,c->map + pos);
}
else {
if (lseek(c->fd,pos,SEEK_SET) == -1) return -1;
while (len > 0) {
int r;
do
r = read(c->fd,buf,len);
while ((r == -1) && (errno == EINTR));
if (r == -1) return -1;
if (r == 0) goto FORMAT;
buf += r;
len -= r;
}
}
return 0;
FORMAT:
errno = EPROTO;
return -1;
}
static int match(struct cdb *c,const unsigned char *key,unsigned long int len,uint32 pos) {
unsigned char buf[32];
unsigned long n;
while (len > 0) {
n = sizeof buf;
if (n > len) n = len;
if (cdb_read(c,buf,n,pos) == -1) return -1;
if (byte_diff(buf,n,key)) return 0;
pos += n;
key += n;
len -= n;
}
return 1;
}
int cdb_findnext(struct cdb *c,const unsigned char *key,unsigned long int len) {
unsigned char buf[8];
uint32 pos;
uint32 u;
if (!c->loop) {
u = cdb_hash(key,len);
if (cdb_read(c,buf,8,(u << 3) & 2047) == -1) return -1;
uint32_unpack(buf + 4,&c->hslots);
if (!c->hslots) return 0;
uint32_unpack(buf,&c->hpos);
c->khash = u;
u >>= 8;
u %= c->hslots;
u <<= 3;
c->kpos = c->hpos + u;
}
while (c->loop < c->hslots) {
if (cdb_read(c,buf,8,c->kpos) == -1) return -1;
uint32_unpack(buf + 4,&pos);
if (!pos) return 0;
c->loop += 1;
c->kpos += 8;
if (c->kpos == c->hpos + (c->hslots << 3)) c->kpos = c->hpos;
uint32_unpack(buf,&u);
if (u == c->khash) {
if (cdb_read(c,buf,8,pos) == -1) return -1;
uint32_unpack(buf,&u);
if (u == len)
switch(match(c,key,len,pos + 8)) {
case -1:
return -1;
case 1:
uint32_unpack(buf + 4,&c->dlen);
c->dpos = pos + 8 + len;
return 1;
}
}
}
return 0;
}
int cdb_find(struct cdb *c,const unsigned char *key,unsigned long int len) {
cdb_findstart(c);
return cdb_findnext(c,key,len);
}

17
cdb/cdb_datalen.3

@ -0,0 +1,17 @@
.TH cdb_datalen 3
.SH NAME
cdb_datalen \- get length of data
.SH SYNTAX
.B #include <cdb.h>
unsigned int cdb_datalen(struct cdb *\fIc\fR);
.SH DESCRIPTION
.B cdb_datalen
returns the length of the data associated with the last key you looked
up with cdb_find or cdb_findnext.
Use cdb_datapos to get the position of the data.
.SH "SEE ALSO"
cdb_datapos(3), cdb_keylen(3), cdb_keypos(3)

17
cdb/cdb_datapos.3

@ -0,0 +1,17 @@
.TH cdb_datapos 3
.SH NAME
cdb_datapos \- get position of data
.SH SYNTAX
.B #include <cdb.h>
uint32 cdb_datapos(struct cdb *\fIc\fR);
.SH DESCRIPTION
.B cdb_datapos
returns the position of the data associated with the last key you looked
up using cdb_find or cdb_findnext.
Use cdb_datalen to get the length of the data.
.SH "SEE ALSO"
cdb_datalen(3), cdb_keypos(3), cdb_keylen(3)

42
cdb/cdb_find.3

@ -0,0 +1,42 @@
.TH cdb_find 3
.SH NAME
cdb_find \- look up a key in a constant database
.SH SYNTAX
.B #include <cdb.h>
.br
.B #include <uint32.h>
int cdb_find(struct cdb *\fIc\fR,char *\fIkey\fR,unsigned int \fIkeylen\fR);
.br
int cdb_datalen(struct cdb *\fIc\fR);
.br
int cdb_datapos(struct cdb *\fIc\fR);
.br
int cdb_findnext(struct cdb *\fIc\fR,char *\fIkey\fR,unsigned int \fIkeylen\fR);
.SH DESCRIPTION
\fBcdb_find\fR looks for \fIkey\fR. If cdb_find returns 0, the database
does not contain that key; stop. If cdb_find returns -1, there was a
read error; abort.
\fBcdb_datalen\fR returns the length of the data associated with the
\fIkey\fR. Use it to allocate a pointer \fIp\fR with enough space to
hold the data.
\fBcdb_datapos\fR returns the position of the data inside the file. Use
it as argument to cdb_read to retrieve the data.
There may be several records under a single key. You can use
\fBcdb_findnext\fR to find the next record under this key.
.SH EXAMPLE
static struct cdb;
if (cdb_find(&c,key,strlen(key)>0) {
char *buf=alloca(cdb_datalen(&c));
cdb_read(&c,buf,cdb_datalen(&c),cdb_datapos(&c));
write(1,buf,cdb_datalen(&c));
.br
}
.SH "SEE ALSO"
cdb_read(3), cdb_init(3), cdb_free(3), cdbmake(1)

19
cdb/cdb_firstkey.3

@ -0,0 +1,19 @@
.TH cdb_firstkey 3
.SH NAME
cdb_firstkey \- find first physical record in constant database
.SH SYNTAX
.B #include <cdb.h>
.br
.B #include <uint32.h>
int cdb_firstkey(struct cdb *\fIc\fR,uint32 *\fIkpos\fR);
.SH DESCRIPTION
\fBcdb_firstkey\fR finds the physically first record in the constant
database.
You can use cdb_datapos or cdb_keypos to get \fIposition\fR and
cdb_datalen and cdb_keylen to get \fIlen\fR.
.SH "SEE ALSO"
cdb_nextkey(3), cdb_successor(3)

17
cdb/cdb_free.3

@ -0,0 +1,17 @@
.TH cdb_free 3
.SH NAME
cdb_free \- close a constant databased
.SH SYNTAX
.B #include <cdb.h>
int cdb_free(struct cdb *\fIc\fR);
.SH DESCRIPTION
.B cdb_free
removes any memory mapping that cdb_init might have established.
It will not close the file descriptor that you passed to cdb_init or
attempt to call free() on the struct cdb pointer.
.SH "SEE ALSO"
cdb_free(3), cdb_read(3), cdb_find(3), cdbmake(1)

19
cdb/cdb_hash.c

@ -0,0 +1,19 @@
#include "cdb.h"
uint32 cdb_hashadd(uint32 h,unsigned char c) {
h += (h << 5);
return h ^ c;
}
uint32 cdb_hash(const unsigned char *buf,unsigned long int len) {
uint32 h;
h = CDB_HASHSTART;
while (len) {
h = cdb_hashadd(h,*buf);
++buf;
--len;
}
return h;
}

20
cdb/cdb_init.3

@ -0,0 +1,20 @@
.TH cdb_init 3
.SH NAME
cdb_init \- open a constant database
.SH SYNTAX
.B #include <cdb.h>
int cdb_init(struct cdb *\fIc\fR,int \fIfd\fR);
.SH DESCRIPTION
.B cdb_init
places information about \fIfd\fR into a struct cdb variable \fIc\fR.
\fIfd\fR has to be a seekable file previously opened for reading.
On systems that support mmap, cdb_init will try to map the whole
constant database into memory.
The inverse operation to cdb_init is cdb_free.
.SH "SEE ALSO"
cdb_free(3), cdb_read(3), cdb_find(3), cdbmake(1)

16
cdb/cdb_keylen.3

@ -0,0 +1,16 @@
.TH cdb_keylen 3
.SH NAME
cdb_keylen \- get length of key
.SH SYNTAX
.B #include <cdb.h>
unsigned int cdb_keylen(struct cdb *\fIc\fR);
.SH DESCRIPTION
.B cdb_keylen
returns the length of the key cdb_firstkey or cdb_nextkey found.
Use cdb_keypos to get the position of the key.
.SH "SEE ALSO"
cdb_keypos(3), cdb_datalen(3), cdb_datapos(3)

16
cdb/cdb_keypos.3

@ -0,0 +1,16 @@
.TH cdb_keypos 3
.SH NAME
cdb_keypos \- get position of key
.SH SYNTAX
.B #include <cdb.h>
uint32 cdb_keypos(struct cdb *\fIc\fR);
.SH DESCRIPTION
.B cdb_keypos
returns the position of the key cdb_firstkey or cdb_nextkey found.
Use cdb_keylen to get the length of the key.
.SH "SEE ALSO"
cdb_keylen(3), cdb_datapos(3), cdb_datalen(3)

148
cdb/cdb_make.c

@ -0,0 +1,148 @@
#define _FILE_OFFSET_BITS 64
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include "cdb.h"
#include "cdb_make.h"
int cdb_make_start(struct cdb_make *c,int fd) {
c->head = 0;
c->split = 0;
c->hash = 0;
c->numentries = 0;
c->fd = fd;
c->pos = sizeof c->final;
buffer_init(&c->b,(void*)write,fd,c->bspace,sizeof c->bspace);
return lseek(fd,c->pos,SEEK_SET);
}
static int posplus(struct cdb_make *c,uint32 len) {
uint32 newpos = c->pos + len;
if (newpos < len) { errno = ENOMEM; return -1; }
c->pos = newpos;
return 0;
}
int cdb_make_addend(struct cdb_make *c,unsigned long int keylen,unsigned long int datalen,uint32 h) {
struct cdb_hplist *head;
head = c->head;
if (!head || (head->num >= CDB_HPLIST)) {
head = (struct cdb_hplist *) malloc(sizeof(struct cdb_hplist));
if (!head) return -1;
head->num = 0;
head->next = c->head;
c->head = head;
}
head->hp[head->num].h = h;
head->hp[head->num].p = c->pos;
++head->num;
++c->numentries;
if (posplus(c,8) == -1) return -1;
if (posplus(c,keylen) == -1) return -1;
if (posplus(c,datalen) == -1) return -1;
return 0;
}
int cdb_make_addbegin(struct cdb_make *c,unsigned long int keylen,unsigned long int datalen) {
char buf[8];
if (keylen > 0xffffffff) { errno = ENOMEM; return -1; }
if (datalen > 0xffffffff) { errno = ENOMEM; return -1; }
uint32_pack(buf,keylen);
uint32_pack(buf + 4,datalen);
if (buffer_putalign(&c->b,buf,8) == -1) return -1;
return 0;
}
int cdb_make_add(struct cdb_make *c,const unsigned char *key,unsigned long int keylen,const unsigned char *data,unsigned long int datalen)
{
if (cdb_make_addbegin(c,keylen,datalen) == -1) return -1;
if (buffer_putalign(&c->b,(char*)key,keylen) == -1) return -1;
if (buffer_putalign(&c->b,(char*)data,datalen) == -1) return -1;
return cdb_make_addend(c,keylen,datalen,cdb_hash(key,keylen));
}
int cdb_make_finish(struct cdb_make *c)
{
char buf[8];
int i;
uint32 len;
uint32 u;
uint32 memsize;
uint32 count;
uint32 where;
struct cdb_hplist *x;
struct cdb_hp *hp;
for (i = 0;i < 256;++i)
c->count[i] = 0;
for (x = c->head;x;x = x->next) {
i = x->num;
while (i--)
++c->count[255 & x->hp[i].h];
}
memsize = 1;
for (i = 0;i < 256;++i) {
u = c->count[i] * 2;
if (u > memsize)
memsize = u;
}
memsize += c->numentries; /* no overflow possible up to now */
u = (uint32) 0 - (uint32) 1;
u /= sizeof(struct cdb_hp);
if (memsize > u) { errno = ENOMEM; return -1; }
c->split = (struct cdb_hp *) malloc(memsize * sizeof(struct cdb_hp));
if (!c->split) return -1;
c->hash = c->split + c->numentries;
u = 0;
for (i = 0;i < 256;++i) {
u += c->count[i]; /* bounded by numentries, so no overflow */
c->start[i] = u;
}
for (x = c->head;x;x = x->next) {
i = x->num;
while (i--)
c->split[--c->start[255 & x->hp[i].h]] = x->hp[i];
}
for (i = 0;i < 256;++i) {
count = c->count[i];
len = count + count; /* no overflow possible */
uint32_pack(c->final + 8 * i,c->pos);
uint32_pack(c->final + 8 * i + 4,len);
for (u = 0;u < len;++u)
c->hash[u].h = c->hash[u].p = 0;
hp = c->split + c->start[i];
for (u = 0;u < count;++u) {
where = (hp->h >> 8) % len;
while (c->hash[where].p)
if (++where == len)
where = 0;
c->hash[where] = *hp++;
}
for (u = 0;u < len;++u) {
uint32_pack(buf,c->hash[u].h);
uint32_pack(buf + 4,c->hash[u].p);
if (buffer_putalign(&c->b,buf,8) == -1) return -1;
if (posplus(c,8) == -1) return -1;
}
}
if (buffer_flush(&c->b) == -1) return -1;
if (lseek(c->fd,0,SEEK_SET) == -1) return -1;
return buffer_putflush(&c->b,c->final,sizeof c->final);
}

19
cdb/cdb_nextkey.3

@ -0,0 +1,19 @@
.TH cdb_nextkey 3
.SH NAME
cdb_nextkey \- find next physical record in constant database
.SH SYNTAX
.B #include <cdb.h>
.br
.B #include <uint32.h>
int cdb_nextkey(struct cdb *\fIc\fR,uint32 *\fIkpos\fR);
.SH DESCRIPTION
\fBcdb_nextkey\fR finds the next physical record in the constant
database.
You can use cdb_datapos or cdb_keypos to get \fIposition\fR and
cdb_datalen and cdb_keylen to get \fIlen\fR.
.SH "SEE ALSO"
cdb_firstkey(3), cdb_successor(3)

20
cdb/cdb_read.3

@ -0,0 +1,20 @@
.TH cdb_read 3
.SH NAME
cdb_read \- read bytes from a constant database
.SH SYNTAX
.B #include <cdb.h>
.br
.B #include <uint32.h>
int cdb_read(struct cdb *\fIc\fR,char *\fIbuf\fR,unsigned int \fIlen\fR,uint32 \fIposition\fR);
.SH DESCRIPTION
\fBcdb_read\fR reads \fIlen\fR bytes starting at \fIposition\fR from
\fIc\fR to buf. You can use cdb_datapos or cdb_keypos to get
\fIposition\fR and cdb_datalen and cdb_keylen to get \fIlen\fR.
\fIbuf\fR needs to point to a memory region large enough to hold
\fIlen\fR bytes.
.SH "SEE ALSO"
cdb_find(3), cdb_init(3), cdb_free(3), cdbmake(1)

21
cdb/cdb_successor.3

@ -0,0 +1,21 @@
.TH cdb_successor 3
.SH NAME
cdb_successor \- find next record
.SH SYNTAX
.B #include <cdb.h>
int cdb_successor(struct cdb *\fIc\fR,char *\fIkey\fR,unsigned int \fIklen\fR);
.SH DESCRIPTION
\fBcdb_successor\fR finds the record that follows \fIkey\fR. If
\fIkey\fR is NULL, cdb_successor finds the first record.
\fBNOTE!\fR The database must not contain keys with more than one
associated record or this API will lead to infinite loops! Use
cdb_firstkey and cdb_nextkey instead.
You can use cdb_datapos or cdb_keypos to get \fIposition\fR and
cdb_datalen and cdb_keylen to get \fIlen\fR.
.SH "SEE ALSO"
cdb_firstkey(3), cdb_nextkey(3)

40
cdb/cdb_traverse.c

@ -0,0 +1,40 @@
#include "cdb.h"
static int doit(struct cdb *c,uint32 *kpos) {
unsigned char buf[8];
uint32 eod,klen;
if (cdb_read(c,buf,4,0)) return -1;
uint32_unpack(buf,&eod);
if (eod<8 || eod-8<*kpos) return 0;
c->kpos=*kpos+8;
if (c->kpos<*kpos) return -1; /* wraparound */
cdb_findstart(c);
c->hslots=1;
if (cdb_read(c,buf,8,*kpos) == -1) return -1;
uint32_unpack(buf,&klen);
uint32_unpack(buf+4,&c->dlen);
c->dpos=c->kpos+klen;
*kpos+=8+klen+c->dlen;
return 1;
}
int cdb_firstkey(struct cdb *c,uint32 *kpos) {
*kpos=2048;
return doit(c,kpos);
}
int cdb_nextkey(struct cdb *c,uint32 *kpos) {
return doit(c,kpos);
}
int cdb_successor(struct cdb *c,unsigned char *key,unsigned long int klen) {
int r;
uint32 kpos;
if (key) {
r=cdb_find(c,key,klen);
if (r<1) return r;
kpos=c->dpos+c->dlen;
} else
kpos=2048;
return doit(c,&kpos);
}

39
cdb_make.h

@ -0,0 +1,39 @@
/* Public domain. */
#ifndef CDB_MAKE_H
#define CDB_MAKE_H
#include "buffer.h"
#include "uint32.h"
#define CDB_HPLIST 1000
struct cdb_hp { uint32 h; uint32 p; } ;
struct cdb_hplist {
struct cdb_hp hp[CDB_HPLIST];
struct cdb_hplist *next;
int num;
} ;
struct cdb_make {
char bspace[8192];
char final[2048];
uint32 count[256];
uint32 start[256];
struct cdb_hplist *head;
struct cdb_hp *split; /* includes space for hash */
struct cdb_hp *hash;
uint32 numentries;
buffer b;
uint32 pos;
int fd;
} ;
extern int cdb_make_start(struct cdb_make *,int);
extern int cdb_make_addbegin(struct cdb_make *,unsigned long int,unsigned long int);
extern int cdb_make_addend(struct cdb_make *,unsigned long int,unsigned long int,uint32);
extern int cdb_make_add(struct cdb_make *,const unsigned char *,unsigned long int,const unsigned char *,unsigned long int);
extern int cdb_make_finish(struct cdb_make *);
#endif
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