--- /dev/null
+/* $Id: it_key.c,v 1.1 2006-11-21 14:32:38 adam Exp $
+ Copyright (C) 1995-2006
+ Index Data ApS
+
+This file is part of the Zebra server.
+
+Zebra is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 2, or (at your option) any later
+version.
+
+Zebra is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+
+*/
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <assert.h>
+
+#include <yaz/xmalloc.h>
+#include <it_key.h>
+
+#ifdef __GNUC__
+#define CODEC_INLINE inline
+#else
+#define CODEC_INLINE
+#endif
+
+void key_logdump_txt(int logmask, const void *p, const char *txt)
+{
+ struct it_key key;
+ if (!txt)
+ txt = "(none)";
+ if (p)
+ {
+ char formstr[128];
+ int i;
+
+ memcpy (&key, p, sizeof(key));
+ assert(key.len > 0 && key.len <= IT_KEY_LEVEL_MAX);
+ *formstr = '\0';
+ for (i = 0; i<key.len; i++)
+ {
+ if (i)
+ strcat(formstr, ".");
+ sprintf(formstr + strlen(formstr), ZINT_FORMAT, key.mem[i]);
+ }
+ yaz_log(logmask, "%s %s", formstr, txt);
+ }
+ else
+ yaz_log(logmask, " (no key) %s",txt);
+}
+
+void key_logdump(int logmask, const void *p)
+{
+ key_logdump_txt(logmask, p, "");
+}
+
+int key_compare_it (const void *p1, const void *p2)
+{
+ int i, l = ((struct it_key *) p1)->len;
+ if (((struct it_key *) p2)->len > l)
+ l = ((struct it_key *) p2)->len;
+ assert (l <= IT_KEY_LEVEL_MAX && l > 0);
+ for (i = 0; i < l; i++)
+ {
+ if (((struct it_key *) p1)->mem[i] != ((struct it_key *) p2)->mem[i])
+ {
+ if (((struct it_key *) p1)->mem[i] > ((struct it_key *) p2)->mem[i])
+ return l-i;
+ else
+ return i-l;
+ }
+ }
+ return 0;
+}
+
+char *key_print_it (const void *p, char *buf)
+{
+ strcpy(buf, "");
+ return buf;
+}
+
+int key_compare (const void *p1, const void *p2)
+{
+ struct it_key i1, i2;
+ int i, l;
+ memcpy (&i1, p1, sizeof(i1));
+ memcpy (&i2, p2, sizeof(i2));
+ l = i1.len;
+ if (i2.len > l)
+ l = i2.len;
+ assert (l <= IT_KEY_LEVEL_MAX && l > 0);
+ for (i = 0; i < l; i++)
+ {
+ if (i1.mem[i] != i2.mem[i])
+ {
+ if (i1.mem[i] > i2.mem[i])
+ return l-i;
+ else
+ return i-l;
+ }
+ }
+ return 0;
+}
+
+zint key_get_seq(const void *p)
+{
+ struct it_key k;
+ memcpy (&k, p, sizeof(k));
+ return k.mem[k.len-1];
+}
+
+zint key_get_segment(const void *p)
+{
+ struct it_key k;
+ memcpy (&k, p, sizeof(k));
+ return k.mem[k.len-2];
+}
+
+int key_qsort_compare (const void *p1, const void *p2)
+{
+ int r;
+ size_t l;
+ char *cp1 = *(char **) p1;
+ char *cp2 = *(char **) p2;
+
+ if ((r = strcmp (cp1, cp2)))
+ return r;
+ l = strlen(cp1)+1;
+ if ((r = key_compare (cp1+l+1, cp2+l+1)))
+ return r;
+ return cp1[l] - cp2[l];
+}
+
+struct iscz1_code_info {
+ struct it_key key;
+};
+
+void *iscz1_start (void)
+{
+ struct iscz1_code_info *p = (struct iscz1_code_info *)
+ xmalloc (sizeof(*p));
+ iscz1_reset(p);
+ return p;
+}
+
+void key_init(struct it_key *key)
+{
+ int i;
+ key->len = 0;
+ for (i = 0; i < IT_KEY_LEVEL_MAX; i++)
+ key->mem[i] = 0;
+}
+
+void iscz1_reset (void *vp)
+{
+ struct iscz1_code_info *p = (struct iscz1_code_info *) vp;
+ int i;
+ p->key.len = 0;
+ for (i = 0; i < IT_KEY_LEVEL_MAX; i++)
+ p->key.mem[i] = 0;
+}
+
+void iscz1_stop (void *p)
+{
+ xfree (p);
+}
+
+/* small encoder that works with unsigneds of any length */
+static CODEC_INLINE void iscz1_encode_int (zint d, char **dst)
+{
+ unsigned char *bp = (unsigned char*) *dst;
+
+ while (d > 127)
+ {
+ *bp++ = (unsigned) (128 | (d & 127));
+ d = d >> 7;
+ }
+ *bp++ = (unsigned) d;
+ *dst = (char *) bp;
+}
+
+/* small decoder that works with unsigneds of any length */
+static CODEC_INLINE zint iscz1_decode_int (unsigned char **src)
+{
+ zint d = 0;
+ unsigned char c;
+ unsigned r = 0;
+
+ while (((c = *(*src)++) & 128))
+ {
+ d += ((zint) (c&127) << r);
+ r += 7;
+ }
+ d += ((zint) c << r);
+ return d;
+}
+
+void iscz1_encode (void *vp, char **dst, const char **src)
+{
+ struct iscz1_code_info *p = (struct iscz1_code_info *) vp;
+ struct it_key tkey;
+ zint d;
+ int i;
+
+ /* 1
+ 3, 2, 9, 12
+ 3, 2, 10, 2
+ 4, 1
+
+ if diff is 0, then there is more ...
+ if diff is non-zero, then _may_ be more
+ */
+ memcpy (&tkey, *src, sizeof(struct it_key));
+
+ /* deal with leader + delta encoding .. */
+ d = 0;
+ assert(tkey.len > 0 && tkey.len <= IT_KEY_LEVEL_MAX);
+ for (i = 0; i < tkey.len; i++)
+ {
+ d = tkey.mem[i] - p->key.mem[i];
+ if (d || i == tkey.len-1)
+ { /* all have been equal until now, now make delta .. */
+ p->key.mem[i] = tkey.mem[i];
+ if (d > 0)
+ {
+ iscz1_encode_int (i + (tkey.len << 3) + 64, dst);
+ i++;
+ iscz1_encode_int (d, dst);
+ }
+ else
+ {
+ iscz1_encode_int (i + (tkey.len << 3), dst);
+ }
+ break;
+ }
+ }
+ /* rest uses absolute encoding ... */
+ for (; i < tkey.len; i++)
+ {
+ iscz1_encode_int (tkey.mem[i], dst);
+ p->key.mem[i] = tkey.mem[i];
+ }
+ (*src) += sizeof(struct it_key);
+}
+
+void iscz1_decode (void *vp, char **dst, const char **src)
+{
+ struct iscz1_code_info *p = (struct iscz1_code_info *) vp;
+ int i;
+
+ int leader = (int) iscz1_decode_int ((unsigned char **) src);
+ i = leader & 7;
+ if (leader & 64)
+ p->key.mem[i] += iscz1_decode_int ((unsigned char **) src);
+ else
+ p->key.mem[i] = iscz1_decode_int ((unsigned char **) src);
+ p->key.len = (leader >> 3) & 7;
+ while (++i < p->key.len)
+ p->key.mem[i] = iscz1_decode_int ((unsigned char **) src);
+ memcpy (*dst, &p->key, sizeof(struct it_key));
+ (*dst) += sizeof(struct it_key);
+}
+
+/*
+ * Local variables:
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ * vim: shiftwidth=4 tabstop=8 expandtab
+ */
+
projects / idzebra-moved-to-github.git / blobdiff