minix/lib/libc/citrus/citrus_lookup.c

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/* $NetBSD: citrus_lookup.c,v 1.7 2012/05/04 16:45:05 joerg Exp $ */
/*-
* Copyright (c)2003 Citrus Project,
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: citrus_lookup.c,v 1.7 2012/05/04 16:45:05 joerg Exp $");
#endif /* LIBC_SCCS and not lint */
#include "namespace.h"
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <limits.h>
#include <unistd.h>
#include <fcntl.h>
#include <paths.h>
#include <dirent.h>
#include <sys/types.h>
#include "citrus_namespace.h"
#include "citrus_bcs.h"
#include "citrus_region.h"
#include "citrus_memstream.h"
#include "citrus_mmap.h"
#include "citrus_db.h"
#include "citrus_db_hash.h"
#include "citrus_lookup.h"
#include "citrus_lookup_file.h"
struct _citrus_lookup {
union {
struct {
struct _citrus_db *db;
struct _citrus_region file;
int num, idx;
struct _db_locator locator;
} db;
struct {
struct _region r;
struct _memstream ms;
} plain;
} u;
#define cl_db u.db.db
#define cl_dbidx u.db.idx
#define cl_dbfile u.db.file
#define cl_dbnum u.db.num
#define cl_dblocator u.db.locator
#define cl_plainr u.plain.r
#define cl_plainms u.plain.ms
int cl_ignore_case;
int cl_rewind;
char *cl_key;
size_t cl_keylen;
int (*cl_next)(struct _citrus_lookup *, struct _region *,
struct _region *);
int (*cl_lookup)(struct _citrus_lookup *, const char *,
struct _region *);
int (*cl_num_entries)(struct _citrus_lookup *);
void (*cl_close)(struct _citrus_lookup *);
};
static int
seq_get_num_entries_db(struct _citrus_lookup *cl)
{
return cl->cl_dbnum;
}
static int
seq_next_db(struct _citrus_lookup *cl,
struct _region *key, struct _region *data)
{
if (cl->cl_key) {
if (key)
_region_init(key, cl->cl_key, cl->cl_keylen);
return _db_lookup_by_s(cl->cl_db, cl->cl_key, data,
&cl->cl_dblocator);
}
if (cl->cl_rewind) {
cl->cl_dbidx = 0;
}
cl->cl_rewind = 0;
if (cl->cl_dbidx >= cl->cl_dbnum)
return ENOENT;
return _db_get_entry(cl->cl_db, cl->cl_dbidx++, key, data);
}
static int
seq_lookup_db(struct _citrus_lookup *cl, const char *key,
struct _region *data)
{
cl->cl_rewind = 0;
free(cl->cl_key);
cl->cl_key = strdup(key);
if (cl->cl_ignore_case)
_bcs_convert_to_lower(cl->cl_key);
cl->cl_keylen = strlen(cl->cl_key);
_db_locator_init(&cl->cl_dblocator);
return _db_lookup_by_s(cl->cl_db, cl->cl_key, data, &cl->cl_dblocator);
}
static void
seq_close_db(struct _citrus_lookup *cl)
{
_db_close(cl->cl_db);
_unmap_file(&cl->cl_dbfile);
}
static int
seq_open_db(struct _citrus_lookup *cl, const char *name)
{
int ret;
struct _region r;
char path[PATH_MAX];
snprintf(path, sizeof(path), "%s.db", name);
ret = _map_file(&r, path);
if (ret)
return ret;
ret = _db_open(&cl->cl_db, &r, _CITRUS_LOOKUP_MAGIC,
_db_hash_std, NULL);
if (ret) {
_unmap_file(&r);
return ret;
}
cl->cl_dbfile = r;
cl->cl_dbnum = _db_get_num_entries(cl->cl_db);
cl->cl_dbidx = 0;
cl->cl_rewind = 1;
cl->cl_lookup = &seq_lookup_db;
cl->cl_next = &seq_next_db;
cl->cl_num_entries = &seq_get_num_entries_db;
cl->cl_close = &seq_close_db;
return 0;
}
#define T_COMM '#'
static int
seq_next_plain(struct _citrus_lookup *cl, struct _region *key,
struct _region *data)
{
const char *p, *q;
size_t len;
if (cl->cl_rewind)
_memstream_bind(&cl->cl_plainms, &cl->cl_plainr);
cl->cl_rewind = 0;
retry:
p = _memstream_getln(&cl->cl_plainms, &len);
if (p == NULL)
return ENOENT;
/* ignore comment */
q = memchr(p, T_COMM, len);
if (q) {
len = q-p;
}
/* ignore trailing spaces */
_bcs_trunc_rws_len(p, &len);
p = _bcs_skip_ws_len(p, &len);
q = _bcs_skip_nonws_len(p, &len);
if (p==q)
goto retry;
if (cl->cl_key && ((size_t)(q-p) != cl->cl_keylen ||
memcmp(p, cl->cl_key, (size_t)(q-p)) != 0))
goto retry;
/* found a entry */
if (key)
_region_init(key, __UNCONST(p), (size_t)(q-p));
p = _bcs_skip_ws_len(q, &len);
if (data)
_region_init(data, len ? __UNCONST(p) : NULL, len);
return 0;
}
static int
seq_get_num_entries_plain(struct _citrus_lookup *cl)
{
int num;
num = 0;
while (seq_next_plain(cl, NULL, NULL) == 0)
num++;
return num;
}
static int
seq_lookup_plain(struct _citrus_lookup *cl, const char *key,
struct _region *data)
{
size_t len;
const char *p;
cl->cl_rewind = 0;
free(cl->cl_key);
cl->cl_key = strdup(key);
if (cl->cl_ignore_case)
_bcs_convert_to_lower(cl->cl_key);
cl->cl_keylen = strlen(cl->cl_key);
_memstream_bind(&cl->cl_plainms, &cl->cl_plainr);
p = _memstream_matchline(&cl->cl_plainms, cl->cl_key, &len, 0);
if (p == NULL)
return ENOENT;
if (data)
_region_init(data, __UNCONST(p), len);
return 0;
}
static void
seq_close_plain(struct _citrus_lookup *cl)
{
_unmap_file(&cl->cl_plainr);
}
static int
seq_open_plain(struct _citrus_lookup *cl, const char *name)
{
int ret;
/* open read stream */
ret = _map_file(&cl->cl_plainr, name);
if (ret)
return ret;
cl->cl_rewind = 1;
cl->cl_next = &seq_next_plain;
cl->cl_lookup = &seq_lookup_plain;
cl->cl_num_entries = &seq_get_num_entries_plain;
cl->cl_close = &seq_close_plain;
return 0;
}
int
_citrus_lookup_seq_open(struct _citrus_lookup **rcl, const char *name,
int ignore_case)
{
int ret;
struct _citrus_lookup *cl;
cl = malloc(sizeof(*cl));
if (cl == NULL)
return ENOMEM;
cl->cl_key = NULL;
cl->cl_keylen = 0;
cl->cl_ignore_case = ignore_case;
ret = seq_open_db(cl, name);
if (ret == ENOENT)
ret = seq_open_plain(cl, name);
if (!ret)
*rcl = cl;
else
free(cl);
return ret;
}
void
_citrus_lookup_seq_rewind(struct _citrus_lookup *cl)
{
cl->cl_rewind = 1;
free(cl->cl_key);
cl->cl_key = NULL;
cl->cl_keylen = 0;
}
int
_citrus_lookup_seq_next(struct _citrus_lookup *cl,
struct _region *key, struct _region *data)
{
return (*cl->cl_next)(cl, key, data);
}
int
_citrus_lookup_seq_lookup(struct _citrus_lookup *cl, const char *key,
struct _region *data)
{
return (*cl->cl_lookup)(cl, key, data);
}
int
_citrus_lookup_get_number_of_entries(struct _citrus_lookup *cl)
{
return (*cl->cl_num_entries)(cl);
}
void
_citrus_lookup_seq_close(struct _citrus_lookup *cl)
{
free(cl->cl_key);
(*cl->cl_close)(cl);
free(cl);
}
char *
_citrus_lookup_simple(const char *name, const char *key,
char *linebuf, size_t linebufsize, int ignore_case)
{
int ret;
struct _citrus_lookup *cl;
struct _region data;
ret = _citrus_lookup_seq_open(&cl, name, ignore_case);
if (ret)
return NULL;
ret = _citrus_lookup_seq_lookup(cl, key, &data);
if (ret) {
_citrus_lookup_seq_close(cl);
return NULL;
}
snprintf(linebuf, linebufsize, "%.*s",
(int)_region_size(&data), (const char *)_region_head(&data));
_citrus_lookup_seq_close(cl);
return linebuf;
}