Permalink
Fetching contributors…
Cannot retrieve contributors at this time
169 lines (145 sloc) 4.46 KB
/*
* Copyright (c) 2007, Novell Inc.
*
* This program is licensed under the BSD license, read LICENSE.BSD
* for further information
*/
#include <string.h>
#include "util.h"
#include "strpool.h"
#define STRING_BLOCK 2047
#define STRINGSPACE_BLOCK 65535
void
stringpool_init(Stringpool *ss, const char *strs[])
{
unsigned totalsize = 0;
unsigned count;
memset(ss, 0, sizeof(*ss));
/* count number and total size of predefined strings */
for (count = 0; strs[count]; count++)
totalsize += strlen(strs[count]) + 1;
/* alloc appropriate space */
ss->stringspace = solv_extend_resize(0, totalsize, 1, STRINGSPACE_BLOCK);
ss->strings = solv_extend_resize(0, count, sizeof(Offset), STRING_BLOCK);
/* now copy predefined strings into allocated space */
ss->sstrings = 0;
for (count = 0; strs[count]; count++)
{
strcpy(ss->stringspace + ss->sstrings, strs[count]);
ss->strings[count] = ss->sstrings;
ss->sstrings += strlen(strs[count]) + 1;
}
ss->nstrings = count;
}
void
stringpool_free(Stringpool *ss)
{
solv_free(ss->strings);
solv_free(ss->stringspace);
solv_free(ss->stringhashtbl);
}
void
stringpool_freehash(Stringpool *ss)
{
ss->stringhashtbl = solv_free(ss->stringhashtbl);
ss->stringhashmask = 0;
}
void
stringpool_init_empty(Stringpool *ss)
{
const char *emptystrs[] = {
"<NULL>",
"",
0,
};
stringpool_init(ss, emptystrs);
}
void
stringpool_clone(Stringpool *ss, Stringpool *from)
{
memset(ss, 0, sizeof(*ss));
ss->strings = solv_extend_resize(0, from->nstrings, sizeof(Offset), STRING_BLOCK);
memcpy(ss->strings, from->strings, from->nstrings * sizeof(Offset));
ss->stringspace = solv_extend_resize(0, from->sstrings, 1, STRINGSPACE_BLOCK);
memcpy(ss->stringspace, from->stringspace, from->sstrings);
ss->nstrings = from->nstrings;
ss->sstrings = from->sstrings;
}
Id
stringpool_strn2id(Stringpool *ss, const char *str, unsigned int len, int create)
{
Hashval h, hh, hashmask, oldhashmask;
int i;
Id id;
Hashtable hashtbl;
if (!str)
return STRID_NULL;
if (!len)
return STRID_EMPTY;
hashmask = oldhashmask = ss->stringhashmask;
hashtbl = ss->stringhashtbl;
/* expand hashtable if needed */
if ((Hashval)ss->nstrings * 2 > hashmask)
{
solv_free(hashtbl);
/* realloc hash table */
ss->stringhashmask = hashmask = mkmask(ss->nstrings + STRING_BLOCK);
ss->stringhashtbl = hashtbl = (Hashtable)solv_calloc(hashmask + 1, sizeof(Id));
/* rehash all strings into new hashtable */
for (i = 1; i < ss->nstrings; i++)
{
h = strhash(ss->stringspace + ss->strings[i]) & hashmask;
hh = HASHCHAIN_START;
while (hashtbl[h] != 0)
h = HASHCHAIN_NEXT(h, hh, hashmask);
hashtbl[h] = i;
}
}
/* compute hash and check for match */
h = strnhash(str, len) & hashmask;
hh = HASHCHAIN_START;
while ((id = hashtbl[h]) != 0)
{
if(!memcmp(ss->stringspace + ss->strings[id], str, len)
&& ss->stringspace[ss->strings[id] + len] == 0)
break;
h = HASHCHAIN_NEXT(h, hh, hashmask);
}
if (id || !create) /* exit here if string found */
return id;
/* this should be a test for a flag that tells us if the
* correct blocking is used, but adding a flag would break
* the ABI. So we use the existance of the hash area as
* indication instead */
if (!oldhashmask)
{
ss->stringspace = solv_extend_resize(ss->stringspace, ss->sstrings + len + 1, 1, STRINGSPACE_BLOCK);
ss->strings = solv_extend_resize(ss->strings, ss->nstrings + 1, sizeof(Offset), STRING_BLOCK);
}
/* generate next id and save in table */
id = ss->nstrings++;
hashtbl[h] = id;
ss->strings = solv_extend(ss->strings, id, 1, sizeof(Offset), STRING_BLOCK);
ss->strings[id] = ss->sstrings; /* we will append to the end */
/* append string to stringspace */
ss->stringspace = solv_extend(ss->stringspace, ss->sstrings, len + 1, 1, STRINGSPACE_BLOCK);
memcpy(ss->stringspace + ss->sstrings, str, len);
ss->stringspace[ss->sstrings + len] = 0;
ss->sstrings += len + 1;
return id;
}
Id
stringpool_str2id(Stringpool *ss, const char *str, int create)
{
if (!str)
return STRID_NULL;
if (!*str)
return STRID_EMPTY;
return stringpool_strn2id(ss, str, (unsigned int)strlen(str), create);
}
void
stringpool_shrink(Stringpool *ss)
{
ss->stringspace = solv_extend_resize(ss->stringspace, ss->sstrings, 1, STRINGSPACE_BLOCK);
ss->strings = solv_extend_resize(ss->strings, ss->nstrings, sizeof(Offset), STRING_BLOCK);
}