dctrl-tools/lib/fieldtrie.c

114 lines
3.1 KiB
C

/* dctrl-tools - Debian control file inspection tools
Copyright © 2003, 2004, 2005, 2007 Antti-Juhani Kaijanaho
This program 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 of the License, or
(at your option) any later version.
This program 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 Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <assert.h>
#include <ctype.h>
#include <string.h>
#include "fieldtrie.h"
#include "msg.h"
struct field_bucket {
struct field_attr attr;
struct field_bucket * next;
};
struct fieldtrie_private {
size_t nextfree;
/* A one-level trie listing all field names occurring in the
* atomic predicates. */
struct field_bucket * fields[UCHAR_MAX];
/* An array mapping each field inx to its attributes */
struct field_attr * field_map[65536];
};
static struct fieldtrie_private trie;
void fieldtrie_init(void)
{
for (size_t i = 0; i < UCHAR_MAX; i++) {
trie.fields[i] = 0;
}
trie.nextfree = 0;
}
struct field_attr *fieldtrie_insert_n(char const * s, size_t slen)
{
struct field_attr *l_attr = fieldtrie_lookup(s, slen);
if (l_attr != 0) return l_attr;
struct field_bucket * b = malloc(sizeof *b);
if (b == 0) fatal_enomem(0);
char *name = malloc(slen+1);
if (name == 0) fatal_enomem(0);
strncpy(name, s, slen);
(name)[slen] = '\0';
*(char**)&b->attr.name = name;
*(size_t*)&b->attr.namelen = slen;
assert(trie.nextfree < sizeof trie.field_map / sizeof *trie.field_map);
*(size_t*)&b->attr.inx = trie.nextfree++;
b->attr.is_show_field = 0;
b->attr.backup_field = (size_t)-1;
unsigned char c = tolower((unsigned char)(b->attr.name[0]));
b->next = trie.fields[c];
trie.fields[c] = b;
trie.field_map[b->attr.inx] = &b->attr;
return &b->attr;
}
struct field_attr *fieldtrie_insert(char const * s)
{
return fieldtrie_insert_n(s, strlen(s));
}
struct field_attr *fieldtrie_lookup(char const * s, size_t n)
{
for (struct field_bucket * b = trie.fields[tolower((unsigned char)s[0])];
b != 0;
b = b->next) {
if (n == b->attr.namelen &&
strncasecmp(s, b->attr.name, n) == 0) return &b->attr;
}
return NULL;
}
size_t fieldtrie_count(void)
{
return trie.nextfree;
}
struct field_attr *fieldtrie_get(size_t inx)
{
assert(inx < sizeof trie.field_map / sizeof *trie.field_map);
return trie.field_map[inx];
}
#if 0
void fieldtrie_clear(void)
{
for (size_t i = 0; i < UCHAR_MAX; i++) {
struct field_bucket * b = trie.fields[i];
while (b != 0) {
struct field_bucket * bn = b->next;
free(b);
b = bn;
}
trie->fields[i] = 0;
}
trie->nextfree = 0;
}
#endif