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-rw-r--r--src/cdb/cdb_make.c524
1 files changed, 524 insertions, 0 deletions
diff --git a/src/cdb/cdb_make.c b/src/cdb/cdb_make.c
new file mode 100644
index 000000000..b5ce28eeb
--- /dev/null
+++ b/src/cdb/cdb_make.c
@@ -0,0 +1,524 @@
+/* $Id: cdb_init.c,v 1.12 2008-11-06 18:07:04 mjt Exp $
+ * cdb_init, cdb_free and cdb_read routines
+ *
+ * This file is a part of tinycdb package by Michael Tokarev, mjt@corpit.ru.
+ * Public domain.
+ */
+
+#include "cdb.h"
+
+void cdb_pack(unsigned num, unsigned char buf[4])
+{
+ buf[0] = num & 255;
+ num >>= 8;
+ buf[1] = num & 255;
+ num >>= 8;
+ buf[2] = num & 255;
+ buf[3] = num >> 8;
+}
+
+int cdb_make_start(struct cdb_make *cdbmp, int fd)
+{
+ memset (cdbmp, 0, sizeof(*cdbmp));
+ cdbmp->cdb_fd = fd;
+ cdbmp->cdb_dpos = 2048;
+ cdbmp->cdb_bpos = cdbmp->cdb_buf + 2048;
+ return 0;
+}
+
+int
+_cdb_make_fullwrite(int fd, const unsigned char *buf, unsigned len)
+{
+ while (len) {
+ int l = write (fd, buf, len);
+ if (l > 0) {
+ len -= l;
+ buf += l;
+ }
+ else if (l < 0 && errno != EINTR)
+ return -1;
+ }
+ return 0;
+}
+
+int
+_cdb_make_flush(struct cdb_make *cdbmp)
+{
+ unsigned len = cdbmp->cdb_bpos - cdbmp->cdb_buf;
+ if (len) {
+ if (_cdb_make_fullwrite (cdbmp->cdb_fd, cdbmp->cdb_buf, len) < 0)
+ return -1;
+ cdbmp->cdb_bpos = cdbmp->cdb_buf;
+ }
+ return 0;
+}
+
+int
+_cdb_make_write(struct cdb_make *cdbmp, const unsigned char *ptr, unsigned len)
+{
+ unsigned l = sizeof(cdbmp->cdb_buf) - (cdbmp->cdb_bpos - cdbmp->cdb_buf);
+ cdbmp->cdb_dpos += len;
+ if (len > l) {
+ memcpy (cdbmp->cdb_bpos, ptr, l);
+ cdbmp->cdb_bpos += l;
+ if (_cdb_make_flush (cdbmp) < 0)
+ return -1;
+ ptr += l;
+ len -= l;
+ l = len / sizeof(cdbmp->cdb_buf);
+ if (l) {
+ l *= sizeof(cdbmp->cdb_buf);
+ if (_cdb_make_fullwrite (cdbmp->cdb_fd, ptr, l) < 0)
+ return -1;
+ ptr += l;
+ len -= l;
+ }
+ }
+ if (len) {
+ memcpy (cdbmp->cdb_bpos, ptr, len);
+ cdbmp->cdb_bpos += len;
+ }
+ return 0;
+}
+
+static int cdb_make_finish_internal(struct cdb_make *cdbmp)
+{
+ unsigned hcnt[256]; /* hash table counts */
+ unsigned hpos[256]; /* hash table positions */
+ struct cdb_rec *htab;
+ unsigned char *p;
+ struct cdb_rl *rl;
+ unsigned hsize;
+ unsigned t, i;
+
+ if (((0xffffffff - cdbmp->cdb_dpos) >> 3) < cdbmp->cdb_rcnt)
+ return errno = ENOMEM, -1;
+
+ /* count htab sizes and reorder reclists */
+ hsize = 0;
+ for (t = 0; t < 256; ++t) {
+ struct cdb_rl *rlt = NULL;
+ i = 0;
+ rl = cdbmp->cdb_rec[t];
+ while (rl) {
+ struct cdb_rl *rln = rl->next;
+ rl->next = rlt;
+ rlt = rl;
+ i += rl->cnt;
+ rl = rln;
+ }
+ cdbmp->cdb_rec[t] = rlt;
+ if (hsize < (hcnt[t] = i << 1))
+ hsize = hcnt[t];
+ }
+
+ /* allocate memory to hold max htable */
+ htab = (struct cdb_rec*) malloc ((hsize + 2) * sizeof(struct cdb_rec));
+ if (!htab)
+ return errno = ENOENT, -1;
+ p = (unsigned char *) htab;
+ htab += 2;
+
+ /* build hash tables */
+ for (t = 0; t < 256; ++t) {
+ unsigned len, hi;
+ hpos[t] = cdbmp->cdb_dpos;
+ if ((len = hcnt[t]) == 0)
+ continue;
+ for (i = 0; i < len; ++i)
+ htab[i].hval = htab[i].rpos = 0;
+ for (rl = cdbmp->cdb_rec[t]; rl; rl = rl->next)
+ for (i = 0; i < rl->cnt; ++i) {
+ hi = (rl->rec[i].hval >> 8) % len;
+ while (htab[hi].rpos)
+ if (++hi == len)
+ hi = 0;
+ htab[hi] = rl->rec[i];
+ }
+ for (i = 0; i < len; ++i) {
+ cdb_pack (htab[i].hval, p + (i << 3));
+ cdb_pack (htab[i].rpos, p + (i << 3) + 4);
+ }
+ if (_cdb_make_write (cdbmp, p, len << 3) < 0) {
+ free (p);
+ return -1;
+ }
+ }
+ free (p);
+ if (_cdb_make_flush (cdbmp) < 0)
+ return -1;
+ p = cdbmp->cdb_buf;
+ for (t = 0; t < 256; ++t) {
+ cdb_pack (hpos[t], p + (t << 3));
+ cdb_pack (hcnt[t], p + (t << 3) + 4);
+ }
+ if (lseek (cdbmp->cdb_fd, 0, 0) != 0 || _cdb_make_fullwrite (cdbmp->cdb_fd,
+ p, 2048) != 0)
+ return -1;
+
+ return 0;
+}
+
+static void cdb_make_free(struct cdb_make *cdbmp)
+{
+ unsigned t;
+ for (t = 0; t < 256; ++t) {
+ struct cdb_rl *rl = cdbmp->cdb_rec[t];
+ while (rl) {
+ struct cdb_rl *tm = rl;
+ rl = rl->next;
+ free (tm);
+ }
+ }
+}
+
+int cdb_make_finish(struct cdb_make *cdbmp)
+{
+ int r = cdb_make_finish_internal (cdbmp);
+ cdb_make_free (cdbmp);
+ return r;
+}
+
+int
+_cdb_make_add(struct cdb_make *cdbmp, unsigned hval, const void *key,
+ unsigned klen, const void *val, unsigned vlen)
+{
+ unsigned char rlen[8];
+ struct cdb_rl *rl;
+ unsigned i;
+ if (klen > 0xffffffff - (cdbmp->cdb_dpos + 8) || vlen > 0xffffffff
+ - (cdbmp->cdb_dpos + klen + 8))
+ return errno = ENOMEM, -1;
+ i = hval & 255;
+ rl = cdbmp->cdb_rec[i];
+ if (!rl || rl->cnt >= sizeof(rl->rec) / sizeof(rl->rec[0])) {
+ rl = (struct cdb_rl*) malloc (sizeof(struct cdb_rl));
+ if (!rl)
+ return errno = ENOMEM, -1;
+ rl->cnt = 0;
+ rl->next = cdbmp->cdb_rec[i];
+ cdbmp->cdb_rec[i] = rl;
+ }
+ i = rl->cnt++;
+ rl->rec[i].hval = hval;
+ rl->rec[i].rpos = cdbmp->cdb_dpos;
+ ++cdbmp->cdb_rcnt;
+ cdb_pack (klen, rlen);
+ cdb_pack (vlen, rlen + 4);
+ if (_cdb_make_write (cdbmp, rlen, 8) < 0 || _cdb_make_write (cdbmp, key,
+ klen) < 0 || _cdb_make_write (cdbmp, val, vlen) < 0)
+ return -1;
+ return 0;
+}
+
+int cdb_make_add(struct cdb_make *cdbmp, const void *key, unsigned klen,
+ const void *val, unsigned vlen)
+{
+ return _cdb_make_add (cdbmp, cdb_hash (key, klen), key, klen, val, vlen);
+}
+
+static void fixup_rpos(struct cdb_make *cdbmp, unsigned rpos, unsigned rlen)
+{
+ unsigned i;
+ struct cdb_rl *rl;
+ register struct cdb_rec *rp, *rs;
+ for (i = 0; i < 256; ++i) {
+ for (rl = cdbmp->cdb_rec[i]; rl; rl = rl->next)
+ for (rs = rl->rec, rp = rs + rl->cnt; --rp >= rs;)
+ if (rp->rpos <= rpos)
+ goto nexthash;
+ else
+ rp->rpos -= rlen;
+ nexthash: ;
+ }
+}
+
+static int remove_record(struct cdb_make *cdbmp, unsigned rpos, unsigned rlen)
+{
+ unsigned pos, len;
+ int r, fd;
+
+ len = cdbmp->cdb_dpos - rpos - rlen;
+ cdbmp->cdb_dpos -= rlen;
+ if (!len)
+ return 0; /* it was the last record, nothing to do */
+ pos = rpos;
+ fd = cdbmp->cdb_fd;
+ do {
+ r = len > sizeof(cdbmp->cdb_buf) ? sizeof(cdbmp->cdb_buf) : len;
+ if (lseek (fd, pos + rlen, SEEK_SET) < 0 || (r = read (fd,
+ cdbmp->cdb_buf, r)) <= 0)
+ return -1;
+ if (lseek (fd, pos, SEEK_SET) < 0 || _cdb_make_fullwrite (fd,
+ cdbmp->cdb_buf, r) < 0)
+ return -1;
+ pos += r;
+ len -= r;
+ } while (len);
+ g_assert (cdbmp->cdb_dpos == pos);
+ fixup_rpos (cdbmp, rpos, rlen);
+ return 0;
+}
+
+static int zerofill_record(struct cdb_make *cdbmp, unsigned rpos, unsigned rlen)
+{
+ if (rpos + rlen == cdbmp->cdb_dpos) {
+ cdbmp->cdb_dpos = rpos;
+ return 0;
+ }
+ if (lseek (cdbmp->cdb_fd, rpos, SEEK_SET) < 0)
+ return -1;
+ memset (cdbmp->cdb_buf, 0, sizeof(cdbmp->cdb_buf));
+ cdb_pack (rlen - 8, cdbmp->cdb_buf + 4);
+ for (;;) {
+ rpos = rlen > sizeof(cdbmp->cdb_buf) ? sizeof(cdbmp->cdb_buf) : rlen;
+ if (_cdb_make_fullwrite (cdbmp->cdb_fd, cdbmp->cdb_buf, rpos) < 0)
+ return -1;
+ rlen -= rpos;
+ if (!rlen)
+ return 0;
+ memset (cdbmp->cdb_buf + 4, 0, 4);
+ }
+}
+
+/* return: 0 = not found, 1 = error, or record length */
+static unsigned match(struct cdb_make *cdbmp, unsigned pos, const char *key,
+ unsigned klen)
+{
+ int len;
+ unsigned rlen;
+ if (lseek (cdbmp->cdb_fd, pos, SEEK_SET) < 0)
+ return 1;
+ if (read (cdbmp->cdb_fd, cdbmp->cdb_buf, 8) != 8)
+ return 1;
+ if (cdb_unpack (cdbmp->cdb_buf) != klen)
+ return 0;
+
+ /* record length; check its validity */
+ rlen = cdb_unpack (cdbmp->cdb_buf + 4);
+ if (rlen > cdbmp->cdb_dpos - pos - klen - 8)
+ return errno = EPROTO, 1; /* someone changed our file? */
+ rlen += klen + 8;
+
+ while (klen) {
+ len = klen > sizeof(cdbmp->cdb_buf) ? sizeof(cdbmp->cdb_buf) : klen;
+ len = read (cdbmp->cdb_fd, cdbmp->cdb_buf, len);
+ if (len <= 0)
+ return 1;
+ if (memcmp (cdbmp->cdb_buf, key, len) != 0)
+ return 0;
+ key += len;
+ klen -= len;
+ }
+
+ return rlen;
+}
+
+static int findrec(struct cdb_make *cdbmp, const void *key, unsigned klen,
+ unsigned hval, enum cdb_put_mode mode)
+{
+ struct cdb_rl *rl;
+ struct cdb_rec *rp, *rs;
+ unsigned r;
+ int seeked = 0;
+ int ret = 0;
+ for (rl = cdbmp->cdb_rec[hval & 255]; rl; rl = rl->next)
+ for (rs = rl->rec, rp = rs + rl->cnt; --rp >= rs;) {
+ if (rp->hval != hval)
+ continue;
+ /*XXX this explicit flush may be unnecessary having
+ * smarter match() that looks into cdb_buf too, but
+ * most of a time here spent in finding hash values
+ * (above), not keys */
+ if (!seeked && _cdb_make_flush (cdbmp) < 0)
+ return -1;
+ seeked = 1;
+ r = match (cdbmp, rp->rpos, key, klen);
+ if (!r)
+ continue;
+ if (r == 1)
+ return -1;
+ ret = 1;
+ switch (mode)
+ {
+ case CDB_FIND_REMOVE:
+ if (remove_record (cdbmp, rp->rpos, r) < 0)
+ return -1;
+ break;
+ case CDB_FIND_FILL0:
+ if (zerofill_record (cdbmp, rp->rpos, r) < 0)
+ return -1;
+ break;
+ default:
+ goto finish;
+ }
+ memmove (rp, rp + 1, (rs + rl->cnt - 1 - rp) * sizeof(*rp));
+ --rl->cnt;
+ --cdbmp->cdb_rcnt;
+ }
+ finish: if (seeked && lseek (cdbmp->cdb_fd, cdbmp->cdb_dpos, SEEK_SET) < 0)
+ return -1;
+ return ret;
+}
+
+int cdb_make_find(struct cdb_make *cdbmp, const void *key, unsigned klen,
+ enum cdb_put_mode mode)
+{
+ return findrec (cdbmp, key, klen, cdb_hash (key, klen), mode);
+}
+
+int cdb_make_exists(struct cdb_make *cdbmp, const void *key, unsigned klen)
+{
+ return cdb_make_find (cdbmp, key, klen, CDB_FIND);
+}
+
+int cdb_make_put(struct cdb_make *cdbmp, const void *key, unsigned klen,
+ const void *val, unsigned vlen, enum cdb_put_mode mode)
+{
+ unsigned hval = cdb_hash (key, klen);
+ int r;
+
+ switch (mode)
+ {
+ case CDB_PUT_REPLACE:
+ case CDB_PUT_INSERT:
+ case CDB_PUT_WARN:
+ case CDB_PUT_REPLACE0:
+ r = findrec (cdbmp, key, klen, hval, mode);
+ if (r < 0)
+ return -1;
+ if (r && mode == CDB_PUT_INSERT)
+ return errno = EEXIST, 1;
+ break;
+
+ case CDB_PUT_ADD:
+ r = 0;
+ break;
+
+ default:
+ return errno = EINVAL, -1;
+ }
+
+ if (_cdb_make_add (cdbmp, hval, key, klen, val, vlen) < 0)
+ return -1;
+
+ return r;
+}
+
+unsigned
+cdb_unpack(const unsigned char buf[4])
+{
+ unsigned n = buf[3];
+ n <<= 8; n |= buf[2];
+ n <<= 8; n |= buf[1];
+ n <<= 8; n |= buf[0];
+ return n;
+}
+
+int
+cdb_seqnext(unsigned *cptr, struct cdb *cdbp) {
+ unsigned klen, vlen;
+ unsigned pos = *cptr;
+ unsigned dend = cdbp->cdb_dend;
+ const unsigned char *mem = cdbp->cdb_mem;
+ if (pos > dend - 8)
+ return 0;
+ klen = cdb_unpack(mem + pos);
+ vlen = cdb_unpack(mem + pos + 4);
+ pos += 8;
+ if (dend - klen < pos || dend - vlen < pos + klen)
+ return errno = EPROTO, -1;
+ cdbp->cdb_kpos = pos;
+ cdbp->cdb_klen = klen;
+ cdbp->cdb_vpos = pos + klen;
+ cdbp->cdb_vlen = vlen;
+ *cptr = pos + klen + vlen;
+ return 1;
+}
+
+/* read a chunk from file, ignoring interrupts (EINTR) */
+
+int
+cdb_bread(int fd, void *buf, int len)
+{
+ int l;
+ while(len > 0) {
+ do l = read(fd, buf, len);
+ while(l < 0 && errno == EINTR);
+ if (l <= 0) {
+ if (!l)
+ errno = EIO;
+ return -1;
+ }
+ buf = (char*)buf + l;
+ len -= l;
+ }
+ return 0;
+}
+
+/* find a given key in cdb file, seek a file pointer to it's value and
+ place data length to *dlenp. */
+
+int
+cdb_seek(int fd, const void *key, unsigned klen, unsigned *dlenp)
+{
+ unsigned htstart; /* hash table start position */
+ unsigned htsize; /* number of elements in a hash table */
+ unsigned httodo; /* hash table elements left to look */
+ unsigned hti; /* hash table index */
+ unsigned pos; /* position in a file */
+ unsigned hval; /* key's hash value */
+ unsigned char rbuf[64]; /* read buffer */
+ int needseek = 1; /* if we should seek to a hash slot */
+
+ hval = cdb_hash(key, klen);
+ pos = (hval & 0xff) << 3; /* position in TOC */
+ /* read the hash table parameters */
+ if (lseek(fd, pos, SEEK_SET) < 0 || cdb_bread(fd, rbuf, 8) < 0)
+ return -1;
+ if ((htsize = cdb_unpack(rbuf + 4)) == 0)
+ return 0;
+ hti = (hval >> 8) % htsize; /* start position in hash table */
+ httodo = htsize;
+ htstart = cdb_unpack(rbuf);
+
+ for(;;) {
+ if (needseek && lseek(fd, htstart + (hti << 3), SEEK_SET) < 0)
+ return -1;
+ if (cdb_bread(fd, rbuf, 8) < 0)
+ return -1;
+ if ((pos = cdb_unpack(rbuf + 4)) == 0) /* not found */
+ return 0;
+
+ if (cdb_unpack(rbuf) != hval) /* hash value not matched */
+ needseek = 0;
+ else { /* hash value matched */
+ if (lseek(fd, pos, SEEK_SET) < 0 || cdb_bread(fd, rbuf, 8) < 0)
+ return -1;
+ if (cdb_unpack(rbuf) == klen) { /* key length matches */
+ /* read the key from file and compare with wanted */
+ unsigned l = klen, c;
+ const char *k = (const char*)key;
+ if (dlenp)
+ *dlenp = cdb_unpack(rbuf + 4); /* save value length */
+ for(;;) {
+ if (!l) /* the whole key read and matches, return */
+ return 1;
+ c = l > sizeof(rbuf) ? sizeof(rbuf) : l;
+ if (cdb_bread(fd, rbuf, c) < 0)
+ return -1;
+ if (memcmp(rbuf, k, c) != 0) /* no, it differs, stop here */
+ break;
+ k += c; l -= c;
+ }
+ }
+ needseek = 1; /* we're looked to other place, should seek back */
+ }
+ if (!--httodo)
+ return 0;
+ if (++hti == htsize) {
+ hti = 0;
+ needseek = 1;
+ }
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-29 00:16:08 +0000