ootp/common/ffdb.c

1475 lines
34 KiB
C

/*
* Copyright (c) 2005 Mark Fullmer
* Copyright (c) 2009 Mark Fullmer and the Ohio State University
* 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.
*
* $Id: ffdb.c 117 2010-03-08 04:24:07Z maf $
*/
#include <sys/fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/param.h>
#include <inttypes.h>
#include <stdlib.h>
#include <unistd.h>
#include <dirent.h>
#include <errno.h>
#if HAVE_STRINGS_H
#include <strings.h>
#endif
#if HAVE_STRING_H
#include <string.h>
#endif
#include "xerr.h"
#include "ffdb.h"
/*
* Simple flat file database. Each key/data pair is stored in an
* individual file. Read and Write operations are atomic to avoid
* race conditions when using dump or tar for live backups. A key
* (file) is locked during a read (shared lock) or write (exclusive lock)
* operation. Non ASCII keys can optionally be encoded in ASCII HEX
* for mapping to readable valid filenames.
*
****
*
* ffdb_ctx_new() allocate new ffdb context
*
* ffdb_ctx_free() free ffdb context
*
* ffdb_ctx_key_pn() create pathname from key
*
* ffdb_ctx_valid() check ffdb context
*
****
*
* ffdb_db_info() ffdb info
*
* ffdb_db_open() open ffdb
*
* ffdb_db_close() close ffdb
*
* ffdb_db_verbose() set ffdb verbosity / debugging
*
****
*
* ffdb_rec_exists() test exists ffdb rec
*
* ffdb_rec_rm() remove ffdb re
*
* ffdb_rec_iter() iterate over ffdb rec's
*
****
*
* ffdb_rec_open() open ffdb rec
*
* ffdb_rec_close() close ffdb rec
*
* ffdb_rec_get() get/read ffdb rec
*
* ffdb_rec_put() put/write ffdb rec
*
* ffdb_rec_lock() lock/unlock ffdb rec
*
*/
/* private functions */
static uint8_t nta(uint8_t b);
static struct ffdb_ctx *ffdb_ctx_new(size_t max_key_size, size_t max_val_size,
uint32_t flags);
static void ffdb_ctx_free(struct ffdb_ctx *ffdbctx);
static int ffdb_ctx_key_pn(struct ffdb_ctx *ffdbctx, struct ffdb_key *key);
static int ffdb_ctx_valid(struct ffdb_ctx *ffdbctx, char *who);
/*
* function: nta()
*
* return ASCII value of low hex nybble
*
*/
static uint8_t nta(uint8_t b)
{
if (b < 10)
b = '0' + b;
else
b = 'A' + (b-10);
return b;
} /* nta */
/*
* function: ffdb_ctx_new()
*
* Allocate a ffdb context with a maximum key size of max_key_size,
* maximum value size of max_val_size.
*
* This is an internal function called by ffdb_db_open()
*
* arguments:
*
* max_key_size - maximum key size
* max_val_size - maximum value size
* flags - FFDB_DB_*
*
* returns: allocated and initialized ffdb_ctx, or 0L on failure.
*
*/
static struct ffdb_ctx *ffdb_ctx_new(size_t max_key_size, size_t max_val_size,
uint32_t flags)
{
struct ffdb_ctx *ffdbctx;
int ret;
ret = -1; /* fail */
if (!(ffdbctx = (struct ffdb_ctx*)malloc(sizeof *ffdbctx))) {
xerr_warn("malloc(ffdbctx)");
goto ffdb_ctx_new_out;
}
bzero(ffdbctx, sizeof *ffdbctx);
ffdbctx->max_key_size = max_key_size;
ffdbctx->max_val_size = max_val_size;
ffdbctx->flags = flags;
ffdbctx->valid = 1;
ffdbctx->rec_open_ref_count = 0;
if (!(ffdbctx->val.val = (char*)malloc(max_val_size))) {
if (ffdbctx->verbose)
xerr_warn("malloc(ffdbctx->val.val)");
goto ffdb_ctx_new_out;
}
ret = 0;
ffdb_ctx_new_out:
if (ret == -1) {
ffdb_ctx_free(ffdbctx);
ffdbctx = (struct ffdb_ctx*)0L;
}
return ffdbctx;
} /* ffdb_ctx_new */
/*
* function: ffdb_ctx_free()
*
* Free resources in ffdb context.
*
* arguments:
*
* ffdbctx - context from ffdb_ctx_new()
*
* This is an internal function called by ffdb_db_close() and/or
* ffdb_db_open()
*
*/
void ffdb_ctx_free(struct ffdb_ctx *ffdbctx)
{
if (ffdb_ctx_valid(ffdbctx, "ffdb_ctx_free") == -1)
return;
if (ffdbctx->base_dir_pn) {
if (ffdbctx->verbose)
xerr_warnx("ffdb_ctx_free(): fatal context has open db.");
return;
}
if (ffdbctx->val.val) {
bzero(ffdbctx->val.val, ffdbctx->max_val_size);
free(ffdbctx->val.val);
ffdbctx->val.val = (void*)0L;
}
/* iter which did not complete to last */
if (ffdbctx->iter_DIR)
closedir(ffdbctx->iter_DIR);
if (ffdbctx) {
bzero(ffdbctx, sizeof (*ffdbctx));
free(ffdbctx);
}
} /* ffdb_ctx_free */
/*
* function: ffdb_ctx_key_pn()
*
* generate full pathname to key
*
* arguments:
*
* ffdbctx - context from ffdb_ctx_new()
* key - initialized key
*
* This is function used internally by ffdb_*
*
* returns: <0 error
* 0 success
*
*/
int ffdb_ctx_key_pn(struct ffdb_ctx *ffdbctx, struct ffdb_key *key)
{
int i, j, bad;
uint8_t *b;
if (ffdb_ctx_valid(ffdbctx, "ffdb_ctx_key_pn") == -1)
return -1;
if (key->size > ffdbctx->max_key_size) {
if (ffdbctx->verbose)
xerr_warnx("ffdb_make_fname(): fatal, max_key_size exceeded.");
return -1;
}
/* encode key to ASCII HEX? */
if (ffdbctx->flags & FFDB_DB_KEY_HEX) {
ffdbctx->key_pn[ffdbctx->base_dir_pn_size + key->size*2+2] = 0;
b = key->key;
j = ffdbctx->base_dir_pn_size + 2;
for (i = 0; i < key->size; ++i) {
ffdbctx->key_pn[i+j] = nta(*b >> 4);
ffdbctx->key_pn[i+j+1] = nta(*b & 0x0F);
++b;
++j;
}
} else {
/*
* keys which map directly to filenames need to be printable and
* not have the pathname seperator
*/
bad = 0;
b = key->key;
for (i = 0; i < key->size; ++i, ++b) {
/* a-z */
if ((*b >= 'a') && (*b <= 'z'))
continue;
/* A-Z */
if ((*b >= 'A') && (*b <= 'Z'))
continue;
/* 0-9 */
if ((*b >= '0') && (*b <= '9'))
continue;
/* .- */
if ((*b == '.') || (*b == '-'))
continue;
bad = 1;
break;
}
/* invalid char in key? */
if (bad) {
if (ffdbctx->verbose)
xerr_warnx("ASCII key not in [a-zA-Z0-9.-]");
return -1;
}
bcopy(key->key, &ffdbctx->key_pn[ffdbctx->base_dir_pn_size]+2,
key->size);
ffdbctx->key_pn[ffdbctx->base_dir_pn_size+key->size+2] = 0;
} /* create pathname */
return 0;
} /* ffdb_ctx_key_pn */
/*
* function: ffdb_ctx_valid()
*
* Check if context is valid
*
* arguments:
*
* ffdbctx - context from ffdb_ctx_new()
* who - null terminated string representing calling function
*
* This is function used internally by ffdb_*
*
* returns: <0 error
* 0 success
*
*/
int ffdb_ctx_valid(struct ffdb_ctx *ffdbctx, char *who)
{
if (!ffdbctx) {
xerr_warnx("%s(): fatal, no context.", who);
return -1;
}
if (!ffdbctx->valid) {
if (ffdbctx->verbose)
xerr_warnx("%s(): fatal, invalid context.", who);
return -1;
}
return 0;
} /* ffdb_ctx_valid */
/*
* function: ffdb_db_info()
*
* Gather stats on ffdb database referenced by base_dir_pn
*
* arguments:
*
* base_dir_pn - base directory of a ffdb
* info - stats including min and max key and value sizes
*
* returns: <0 error
* 0 success
*
*/
int ffdb_db_info(char *base_dir_pn, struct ffdb_info *info)
{
DIR *dir;
struct dirent *di;
struct stat sb;
char *d_path_name;
int base_dir_pn_len, ret, d_namlen;
size_t ts;
ret = -1; /* fail */
dir = (void*)0L;
d_path_name = (void*)0L;
base_dir_pn_len = strlen(base_dir_pn);
bzero(info, sizeof (*info));
/* storage to construct d_path_name as base_dir_pn/d/<filename> */
if (!(d_path_name = (char*)malloc(base_dir_pn_len+4+MAXNAMLEN))) {
xerr_warn("malloc(base_dir_pn_len+4)");
goto ffdb_db_info_out;
}
/* construct d_path_name */
bcopy(base_dir_pn, d_path_name, base_dir_pn_len);
d_path_name[base_dir_pn_len] = '/';
d_path_name[base_dir_pn_len+1] = 'd';
d_path_name[base_dir_pn_len+2] = '/';
d_path_name[base_dir_pn_len+3] = 0;
/* database dir */
if (!(dir = opendir(d_path_name))) {
xerr_warn("opendir(%s)", d_path_name);
goto ffdb_db_info_out;
}
while ((di = readdir(dir))) {
d_namlen = strlen(di->d_name);
if ((d_namlen == 1) && (di->d_name[0] == '.'))
continue;
if ((d_namlen == 2) && (di->d_name[0] == '.') &&
(di->d_name[1] == '.'))
continue;
ts = d_namlen; /* gcc: can't cast up portable */
if (ts > MAXNAMLEN) {
xerr_warnx("fddb_info(): fatal d_namlen >= MAXNAMLEN");
return -1;
}
bcopy(di->d_name, &d_path_name[base_dir_pn_len+3], d_namlen);
d_path_name[base_dir_pn_len+d_namlen+3] = 0;
if (stat(d_path_name, &sb) < 0) {
xerr_warn("stat(%s)", d_path_name);
goto ffdb_db_info_out;
}
/* prime min's */
if (info->num_keys == 0) {
info->min_key_size = d_namlen;
info->min_val_size = sb.st_size;
}
if (d_namlen > info->max_key_size)
info->max_key_size = d_namlen;
if (d_namlen < info->min_key_size)
info->min_key_size = d_namlen;
if (sb.st_size > info->max_val_size)
info->max_val_size = sb.st_size;
if (sb.st_size < info->min_val_size)
info->min_val_size = sb.st_size;
++ info->num_keys;
} /* while more dir entries to read */
ret = 0; /* succes */
ffdb_db_info_out:
if (d_path_name)
free(d_path_name);
if (dir)
closedir(dir);
return ret;
} /* ffdb_db_info */
/*
* function: ffdb_db_open()
*
* Open a flat file database. Database must be closed with ffdb_db_close()
* to release allocated resources.
*
* arguments:
*
* base_dir_pn - base directory of a ffdb
* max_key_size - max size of key (database key)
* max_val_size - max size of value (database key value)
* flags - db flags
* FFDB_DB_KEY_HEX encode keys as ASCII HEX
* FFDB_DB_CREATE create db
* FFDB_DB_SYNC_WRITES enable synchronous writes
* FFDB_DB_STAT_READ verify read size == stat size
* FFDB_DB_CREATE_SOFT create db if it does not exist
* FFDB_DB_VERBOSE verbose error messages
* file_mode - unix mode bits to create files (database keys)
* dir_mode - unix mode bits to create directories (database tree)
*
* returns: allocated and initialized ffdb_ctx on success
* 0 on failure.
*
*/
struct ffdb_ctx *ffdb_db_open(char *base_dir_pn, size_t max_key_size,
size_t max_val_size, uint32_t flags, mode_t file_mode, mode_t dir_mode)
{
struct stat sb;
struct ffdb_ctx *ffdbctx;
size_t key_pn_size, base_dir_pn_size;
int ret, verbose;
if (flags & FFDB_DB_VERBOSE)
verbose = 1;
else
verbose = 0;
ffdbctx = (struct ffdb_ctx*)0L;
ret = -1; /* fail */
base_dir_pn_size = strlen(base_dir_pn) + 1;
/*
* key file is base_dir_pn/d/keyname
* strlen(base_dir_pn) + 3(/d/) + key_name_length + 1(NULL)
*
* hex encoded keys are two ASCII bytes per key byte
*
* String is null terminated. ffdbctx->base_dir_pn_size includes
* space for / (without null).
*
* calcs:
* base_dir_pn = "b"
* base_dir_pn_size = strlen("b")+1 = 2
* 01234567890
* key_pn = "b/d/KEY"
* key_pn = "b/d/AABBCC" (hex)
* key_pn_size = 8 = base_dir_pn_size + 3 + strlen(KEY) = 2 + 3 + 3
* key_pn_size_hex = 11 = base_dir_pn_size + 3 + strlen(KEY)*2 = 2 + 3 + 3*2
*
*
* / = base_dir_pn_size -1
* d = base_dir_pn_size 0
* / = base_dir_pn_size +1
* 0 = base_dir_pn_size +2
*/
/* hex key requires 2 bytes/byte when encoded */
if (flags & FFDB_DB_KEY_HEX)
key_pn_size = base_dir_pn_size + max_key_size*2 + 3;
else
key_pn_size = base_dir_pn_size + max_key_size + 3;
if (key_pn_size > MAXNAMLEN) {
if (verbose)
xerr_warnx("ffdb_db_open(): key_pn_size > MAXNAMELEN");
goto ffdb_db_open_out;
}
if (!(ffdbctx = ffdb_ctx_new(max_key_size, max_val_size, flags))) {
if (verbose)
xerr_warnx("ffdb_ctx_new(): failed");
goto ffdb_db_open_out;
}
ffdbctx->verbose = verbose;
ffdbctx->base_dir_pn_size = base_dir_pn_size;
ffdbctx->file_mode = file_mode;
ffdbctx->key_pn_size = key_pn_size;
/* allocate mem for base dir */
if (!(ffdbctx->base_dir_pn = (char*)malloc(ffdbctx->base_dir_pn_size))) {
if (verbose)
xerr_warn("malloc(ffdbctx->base_dir_pn)");
goto ffdb_db_open_out;
}
/* copy in base_dir_pn */
bcopy(base_dir_pn, ffdbctx->base_dir_pn, ffdbctx->base_dir_pn_size);
/* allocate mem for key pathname */
if (!(ffdbctx->key_pn = (char*)malloc(ffdbctx->key_pn_size))) {
if (verbose)
xerr_warn("malloc(ffdbctx->key_pn)");
goto ffdb_db_open_out;
}
/* base dir of key will always be basedir/ */
bcopy(base_dir_pn, ffdbctx->key_pn, ffdbctx->base_dir_pn_size);
ffdbctx->key_pn[ffdbctx->base_dir_pn_size-1] = '/';
ffdbctx->key_pn[ffdbctx->base_dir_pn_size+0] = 'd';
ffdbctx->key_pn[ffdbctx->base_dir_pn_size+1] = '/';
ffdbctx->key_pn[ffdbctx->base_dir_pn_size+2] = 0;
/* create db dir? */
if ((flags & FFDB_DB_CREATE) || (flags & FFDB_DB_CREATE_SOFT)) {
ret = mkdir(base_dir_pn, dir_mode);
if ((ret < 0) && (errno == EEXIST) && (flags & FFDB_DB_CREATE_SOFT))
goto ffdb_db_open_skip1;
if (ret < 0) {
if (verbose)
xerr_warn("mkdir(%s)", base_dir_pn);
goto ffdb_db_open_out;
}
ffdb_db_open_skip1:
ret = mkdir(ffdbctx->key_pn, dir_mode);
if ((ret < 0) && (errno == EEXIST) && (flags & FFDB_DB_CREATE_SOFT))
goto ffdb_db_open_skip2;
if (ret < 0) {
if (verbose)
xerr_warn("mkdir(%s)", ffdbctx->key_pn);
goto ffdb_db_open_out;
}
} else {
if (stat(ffdbctx->key_pn, &sb) < 0) {
if (verbose)
xerr_warn("stat(%s)", ffdbctx->key_pn);
goto ffdb_db_open_out;
}
if (!S_ISDIR(sb.st_mode)) {
if (verbose)
xerr_warnx("S_ISDIR(%s): failed", ffdbctx->key_pn);
goto ffdb_db_open_out;
}
} /* FFDB_DB_CREATE */
ffdb_db_open_skip2:
ret = 0; /* success */
ffdb_db_open_out:
if (ret == -1) {
if (ffdbctx) {
if (ffdbctx->base_dir_pn) {
bzero(ffdbctx->base_dir_pn, ffdbctx->base_dir_pn_size);
free(ffdbctx->base_dir_pn);
ffdbctx->base_dir_pn = (void*)0L;
}
if (ffdbctx->key_pn) {
bzero(ffdbctx->key_pn, ffdbctx->key_pn_size);
free(ffdbctx->key_pn);
ffdbctx->key_pn = (void*)0L;
}
bzero(ffdbctx, sizeof *ffdbctx);
ffdb_ctx_free(ffdbctx);
ffdbctx = (void*)0L;
} /* ffdbctx */
} /* error */
return ffdbctx;
} /* ffdb_db_open */
/*
* function: ffdb_db_close()
*
* Close a flat file database opened with ffdb_db_open()
*
* arguments:
*
* ffdbctx - ffdb context
*
* returns: <0 failure
* 0 success
*
*/
int ffdb_db_close(struct ffdb_ctx *ffdbctx)
{
if (ffdb_ctx_valid(ffdbctx, "ffdb_db_close") == -1)
return -1;
if (ffdbctx->rec_open_ref_count != 0) {
if (ffdbctx->verbose)
xerr_warnx("ffdb_rec_close(): rec_open_ref_count != 0.");
return -1;
}
if (ffdbctx->base_dir_pn) {
bzero(ffdbctx->base_dir_pn, ffdbctx->base_dir_pn_size);
free(ffdbctx->base_dir_pn);
ffdbctx->base_dir_pn = (void*)0L;
}
if (ffdbctx->key_pn) {
bzero(ffdbctx->key_pn, ffdbctx->key_pn_size);
free(ffdbctx->key_pn);
ffdbctx->key_pn = (void*)0L;
}
bzero(ffdbctx, sizeof *ffdbctx);
ffdb_ctx_free(ffdbctx);
ffdbctx = (void*)0L;
return 0;
} /* ffdb_db_close */
/*
* function: ffdb_db_verbose()
*
* Enable/disable verbose warnings and errors with xerr_* functions.
*
* arguments:
*
* ffdbctx - ffdb context created by ffdb_db_open()
* verbose - verbose level 0=no messages, > 0 to display messages.
*
*/
void ffdb_db_verbose(struct ffdb_ctx *ffdbctx, int verbose)
{
if (ffdb_ctx_valid(ffdbctx, "ffdb_db_verbose") == -1)
return;
ffdbctx->verbose = verbose;
} /* ffdb_db_verbose */
/*
* function: ffdb_db_exists()
*
* Test if a key exists in database.
*
* arguments:
*
* ffdbctx - ffdb context created by ffdb_db_open()
* key - database key to check
*
* returns: <0 error
* 0 key exists
* 1 key does not exist
*/
int ffdb_rec_exists(struct ffdb_ctx *ffdbctx, struct ffdb_key *key)
{
struct stat sb;
int ret;
if (ffdb_ctx_valid(ffdbctx, "ffdb_rec_exists") == -1)
return -1;
/* create pathname */
if (ffdb_ctx_key_pn(ffdbctx, key) < 0) {
if (ffdbctx->verbose)
xerr_warnx("ffdb_ctx_key_pn(): failed");
return -1;
}
ret = stat(ffdbctx->key_pn, &sb);
/* key exists? */
if (ret == 0)
return 0;
/* key does not exist? */
if ((ret <0) && (errno == ENOENT))
return 1;
/* fail? */
if ((ret < 0) && ffdbctx->verbose)
if (ffdbctx->verbose)
xerr_warn("stat(%s)", ffdbctx->key_pn);
return ret;
} /* ffdb_rec_exists */
/*
* function: ffdb_db_exists()
*
* Remove a key from database
*
* arguments:
*
* ffdbctx - ffdb context created by ffdb_db_open()
* key - database key to remove
*
* returns: <0 error
* 0 success (key removed)
*/
int ffdb_rec_rm(struct ffdb_ctx *ffdbctx, struct ffdb_key *key)
{
int ret;
if (ffdb_ctx_valid(ffdbctx, "ffdb_rec_rm") == -1)
return -1;
/* create pathname */
if (ffdb_ctx_key_pn(ffdbctx, key) < 0) {
if (ffdbctx->verbose)
xerr_warnx("ffdb_ctx_key_pn(): failed");
return -1;
}
ret = unlink(ffdbctx->key_pn);
/* success? */
if ((ret < 0) && ffdbctx->verbose)
if (ffdbctx->verbose)
xerr_warn("unlink(%s)", ffdbctx->key_pn);
return ret;
} /* ffdb_rec_rm */
/*
* function: ffdb_rec_iter()
*
* Iterate over keys in a database. The first key is returned
* by setting FFDB_ITER_FIRST. Additional calls to ffdb_db_iter()
* will set FFDB_ITER_NEXT. When no more entries are available
* ffdb_db_iter() will return 1. If the database walk is stopped
* before the last entry, a last call to ffdb_db_iter() must set the
* FFDB_ITER_DONE flag to free allocated resources.
*
* If the FFDB_ITER_DONE flag is set, a record value will be returned
* in val. val is overwritten on each call. The caller is responsible
* for copying this value out to permanent storage if necessary.
*
* arguments:
*
* ffdbctx - ffdb context created by ffdb_db_open()
* key - database key returned
* val - optional database value returned
* iter_flags
* FFDB_ITER_FIRST set on first call
* FFDB_ITER_NEXT set after first call
* FFDB_ITER_GET do ffdb_rec_get() / return value
* FFDB_ITER_DONE clear resources allocated by FIRST
*
* returns: <0 error
* 0 success
* 1 no more entries
*/
int ffdb_rec_iter(struct ffdb_ctx *ffdbctx, struct ffdb_key *key,
struct ffdb_val *val, int iter_flags)
{
struct dirent *di;
int ret, d_namlen;
ret = -1; /* fail */
if (ffdb_ctx_valid(ffdbctx, "ffdb_rec_iter") == -1)
return -1;
if (iter_flags & FFDB_ITER_DONE) {
if (ffdbctx->iter_DIR)
closedir(ffdbctx->iter_DIR);
ffdbctx->iter_DIR = (void*)0L;
return 0;
} /* FFDB_ITER_DONE */
if (iter_flags & FFDB_ITER_FIRST) {
/* just the dir */
ffdbctx->key_pn[ffdbctx->base_dir_pn_size+2] = 0;
/* previous call which did not complete to last entry */
if (ffdbctx->iter_DIR)
closedir(ffdbctx->iter_DIR);
ffdbctx->iter_DIR = (void*)0L;
if (!(ffdbctx->iter_DIR = opendir(ffdbctx->key_pn))) {
xerr_warn("opendir(%s)", ffdbctx->key_pn);
goto ffdb_rec_iter_out;
}
} /* FFDB_ITER_FIRST */
while (1) {
di = readdir(ffdbctx->iter_DIR);
/* last? */
if (!di) {
ret = 1; /* last */
closedir(ffdbctx->iter_DIR);
ffdbctx->iter_DIR = (void*)0L;
goto ffdb_rec_iter_out;
}
d_namlen = strlen(di->d_name);
if ((d_namlen == 1) && (di->d_name[0] == '.'))
continue;
if ((d_namlen == 2) && (di->d_name[0] == '.') &&
(di->d_name[1] == '.'))
continue;
key->key = di->d_name;
key->size = d_namlen;
if (iter_flags & FFDB_ITER_GET) {
ret = ffdb_rec_open(ffdbctx, key, O_RDONLY, FFDB_OP_LOCK_SH);
if (ret != -1) {
ret = ffdb_rec_get(ffdbctx, key, val, 0);
ffdb_rec_close(ffdbctx, key);
}
break;
} else {
ret = 0;
break;
} /* FFDB_ITER_GET */
} /* get next item, not . or .. */
ffdb_rec_iter_out:
return ret;
} /* ffdb_rec_iter */
/*
* function: ffdb_rec_open()
*
* Open a database record for reading/writing.
*
* Once a database record is open ffdb_rec_put(), ffdb_rec_get(), and
* ffdb_rec_get() can be used on the key.
*
* ffdb_rec_close() must be called on an open record to free resources
* allocated by ffdb_rec_open()
*
* arguments:
*
* ffdbctx - ffdb context created by ffdb_db_open()
* key - database key returned
* open_flags - see open(2)
* op_flags -
* FFDB_OP_LOCK_NONE - no locking
* FFDB_OP_LOCK_SH - shared lock
* FFDB_OP_LOCK_EX - exclusive lock
* FFDB_OP_LOCK_NB - non blocking lock
* FFDB_OP_LOCK_UN - unlock
*
* returns: <0 error
* 0 success
*/
int ffdb_rec_open(struct ffdb_ctx *ffdbctx, struct ffdb_key *key,
int open_flags, int op_flags)
{
struct stat sb;
int ret, lock_flags;
extern int errno;
if (ffdb_ctx_valid(ffdbctx, "ffdb_rec_open") == -1)
return -1;
key->fd = -1;
lock_flags = 0;
/* create pathname */
if (ffdb_ctx_key_pn(ffdbctx, key) < 0) {
if (ffdbctx->verbose)
xerr_warnx("ffdb_ctx_key_pn(): failed");
return -1;
}
/* open w. lock? */
if (op_flags & FFDB_OP_LOCK_SH)
#ifdef O_SHLOCK
open_flags |= O_SHLOCK;
#else
lock_flags |= LOCK_SH;
#endif /* O_SHLOCK */
if (op_flags & FFDB_OP_LOCK_EX)
#ifdef O_EXLOCK
open_flags |= O_EXLOCK;
#else
lock_flags |= LOCK_EX;
#endif /* O_EXLOCK */
if (op_flags & FFDB_OP_LOCK_NB) {
open_flags |= O_NONBLOCK;
lock_flags |= LOCK_NB;
}
if (ffdbctx->flags & FFDB_DB_STAT_READ) {
ret = stat(ffdbctx->key_pn, &sb);
/*
* if key does not exist, and may be creating it later, ignore
*/
if (!((ret < 0) && (errno == ENOENT) && (open_flags & O_CREAT))) {
if ((ffdbctx->verbose) && (ret < 0))
xerr_warn("stat(%s)", ffdbctx->key_pn);
if (ret < 0)
goto ffdb_rec_open_out;
if (sb.st_size > ffdbctx->max_val_size)
if (ffdbctx->verbose)
xerr_warnx("ffdb_rec_open(): sb.st_size > max_val_size");
}
} /* FFDB_DB_STAT_READ */
ret = open(ffdbctx->key_pn, open_flags, ffdbctx->file_mode);
if ((ret < 0) && ffdbctx->verbose)
xerr_warn("open(%s)", ffdbctx->key_pn);
key->fd = ret;
if (ret < 0)
goto ffdb_rec_open_out;
if (lock_flags) {
ret = flock(key->fd, lock_flags);
if ((ret < 0) && ffdbctx->verbose)
xerr_warn("flock(%s)", ffdbctx->key_pn);
if (ret < 0)
goto ffdb_rec_open_out;
} /* lock_flags */
ret = 0; /* success */
ffdbctx->rec_open_ref_count ++;
ffdb_rec_open_out:
return ret;
} /* ffdb_rec_open */
/*
* function: ffdb_rec_close()
*
* Close a database record opened with ffdb_rec_open()
*
* arguments:
* ffdbctx - ffdb context created by ffdb_db_open()
* key - database key
*
* returns: <0 error
* 0 success
*/
int ffdb_rec_close(struct ffdb_ctx *ffdbctx, struct ffdb_key *key)
{
int r;
if (ffdb_ctx_valid(ffdbctx, "ffdb_rec_close") == -1)
return -1;
if (key->fd == -1) {
if (ffdbctx->verbose)
xerr_warnx("ffdb_rec_close(): invalid fd.");
return -1;
}
if (ffdbctx->rec_open_ref_count == 0) {
if (ffdbctx->verbose)
xerr_warnx("ffdb_rec_close(): rec_open_ref_count == 0.");
return -1;
}
if (!ffdbctx->valid) {
if (ffdbctx->verbose)
xerr_warnx("ffdb_rec_close(): fatal, invalid context.");
return -1;
}
r = close(key->fd);
key->fd = -1;
ffdbctx->rec_open_ref_count --;
return r;
} /* ffdb_rec_close */
/*
* function: ffdb_rec_get()
*
* Get a database record (value) opened with ffdb_rec_open().
*
* arguments:
* ffdbctx - ffdb context created by ffdb_db_open()
* key - database key (in)
* val - database key value (out)
* op_flags
* FFDB_OP_REWIND_NO - do not rewind() after read()
* FFDB_OP_VAL_ALLOC - allocate a private copy of val for caller
*
* returns: <0 error
* 0 success
*/
int ffdb_rec_get(struct ffdb_ctx *ffdbctx, struct ffdb_key *key,
struct ffdb_val *val, int op_flags)
{
int ret;
ret = -1; /* fail */
if (ffdb_ctx_valid(ffdbctx, "ffdb_rec_get") == -1)
return -1;
if (key->fd == -1) {
if (ffdbctx->verbose)
xerr_warnx("ffdb_rec_get(): invalid fd.");
return -1;
}
val->val = (void*)0L;
/* allocate storage for val? */
if (op_flags & FFDB_OP_VAL_ALLOC) {
if (!(val->val = (char*)malloc(ffdbctx->max_val_size))) {
if (ffdbctx->verbose)
xerr_warn("malloc(val->val)");
goto ffdb_rec_get_out;
}
/* no, use scratch val in context */
} else {
val->val = ffdbctx->val.val;
}
ret = read(key->fd, val->val, ffdbctx->max_val_size);
if (!(op_flags & FFDB_OP_REWIND_NO))
lseek(key->fd, (off_t)0L, SEEK_SET);
if ((ret < 0) && ffdbctx->verbose)
if (ffdbctx->verbose)
xerr_warn("read(%s)", ffdbctx->key_pn);
if (ret < 0)
goto ffdb_rec_get_out;
if (op_flags & FFDB_OP_VAL_ALLOC)
ffdbctx->val.size = ret;
val->size = ret;
ret = 0; /* success */
ffdb_rec_get_out:
return ret;
} /* ffdb_rec_get */
/*
* function: ffdb_rec_put()
*
* Put a database record (value) opened with ffdb_rec_open().
*
* arguments:
* ffdbctx - ffdb context created by ffdb_db_open()
* key - database key (out)
* val - database key value (out)
* op_flags
* FFDB_OP_TRUNCATE_NO do not truncate before write()
* FFDB_OP_REWIND_NO - do not rewind() after write()
*
* returns: <0 error
* 0 success
*/
int ffdb_rec_put(struct ffdb_ctx *ffdbctx, struct ffdb_key *key,
struct ffdb_val *val, int op_flags)
{
int ret;
if (ffdb_ctx_valid(ffdbctx, "ffdb_rec_put") == -1)
return -1;
if (key->fd == -1) {
if (ffdbctx->verbose)
xerr_warnx("ffdb_rec_put(): invalid fd.");
return -1;
}
if (!(op_flags & FFDB_OP_TRUNCATE_NO)) {
ret = ftruncate(key->fd, (off_t)0L);
if (ret < 0) {
if (ffdbctx->verbose)
xerr_warn("ftruncate(%s)", ffdbctx->key_pn);
goto ffdb_rec_put_out;
}
}
ret = write(key->fd, val->val, val->size);
if (ret < 0) {
if (ffdbctx->verbose)
xerr_warn("write(%s)", ffdbctx->key_pn);
goto ffdb_rec_put_out;
}
if (ffdbctx->flags & FFDB_DB_SYNC_WRITES) {
ret = fsync(key->fd);
if (ret < 0) {
if (ffdbctx->verbose)
xerr_warn("fsync(%s)", ffdbctx->key_pn);
goto ffdb_rec_put_out;
}
} /* FFDB_DB_SYNC_WRITES */
if (!(op_flags & FFDB_OP_REWIND_NO)) {
ret = lseek(key->fd, (off_t)0L, SEEK_SET);
if (ret < 0) {
if (ffdbctx->verbose)
xerr_warn("lseek(%s)", ffdbctx->key_pn);
goto ffdb_rec_put_out;
}
}
if (ret < 0)
goto ffdb_rec_put_out;
ret = 0; /* success */
ffdb_rec_put_out:
return ret;
} /* ffdb_rec_put */
/*
* function: ffdb_rec_lock()
*
* Perform flock() operations on database record opened with ffdb_rec_open()
*
* arguments:
* ffdbctx - ffdb context created by ffdb_db_open()
* key - database key
* op_flags
* FFDB_OP_LOCK_NONE - no op
* FFDB_OP_LOCK_SH - shared lock
* FFDB_OP_LOCK_EX - exclusive lock
* FFDB_OP_LOCK_NB - non blocking lock
* FFDB_OP_LOCK_UN - unlock
*
* returns: <0 error
* 0 success
*/
int ffdb_rec_lock(struct ffdb_ctx *ffdbctx, struct ffdb_key *key, int op_flags)
{
int ret, lock_flags;
ret = -1;
lock_flags = 0;
if (ffdb_ctx_valid(ffdbctx, "ffdb_rec_lock") == -1)
return -1;
if (key->fd == -1) {
if (ffdbctx->verbose)
xerr_warnx("ffdb_rec_lock(): invalid fd.");
return -1;
}
if (op_flags & FFDB_OP_LOCK_SH)
lock_flags |= LOCK_SH;
if (op_flags & FFDB_OP_LOCK_EX)
lock_flags |= LOCK_EX;
if (op_flags & FFDB_OP_LOCK_NB)
lock_flags |= LOCK_NB;
if (op_flags & FFDB_OP_LOCK_UN)
lock_flags |= LOCK_UN;
if (lock_flags) {
ret = flock(key->fd, lock_flags);
if ((ret < 0) && ffdbctx->verbose)
xerr_warn("flock(%s)", ffdbctx->key_pn);
if (ret < 0)
goto ffdb_rec_lock_out;
} /* lock_flags */
ret = 0;
ffdb_rec_lock_out:
return ret;
} /* ffdb_rec_lock */
#ifdef FFDB_EXAMPLE
#include <stdio.h>
#include "ffdb.h"
int main(int argc, char **argv)
{
struct ffdb_ctx *ffdbctx;
struct ffdb_key key, key2;
struct ffdb_val val;
struct ffdb_info info;
mode_t file_mode, dir_mode;
int ret;
uint32_t flags;
xerr_setid(argv[0]);
file_mode = S_IRUSR|S_IWUSR;
dir_mode = S_IRWXU;
/**
ffdb_info("/tmp/ffdb2", &info);
printf("info.min_key_size=%lu\n", (unsigned long)info.min_key_size);
printf("info.max_key_size=%lu\n", (unsigned long)info.max_key_size);
printf("info.min_val_size=%lu\n", (unsigned long)info.min_val_size);
printf("info.max_val_size=%lu\n", (unsigned long)info.max_val_size);
printf("info.num_keys=%lu\n", (unsigned long)info.num_keys);
flags = 0;
**/
/***/
ffdbctx = ffdb_db_open("/tmp/ffdb-created", 12, 12,
FFDB_DB_CREATE_SOFT|FFDB_DB_KEY_HEX|FFDB_DB_STAT_READ,
file_mode, dir_mode);
ret = (ffdbctx == 0L);
printf("ffdb_db_open(): %d\n", ret);
ret = ffdb_db_close(ffdbctx);
printf("ffdb_db_close(): %d\n", ret);
/***/
ffdbctx = ffdb_db_open("/tmp/ffdb2", 64, 64,
FFDB_DB_KEY_HEX|FFDB_DB_STAT_READ, file_mode, dir_mode);
ret = (ffdbctx == 0L);
printf("ffdb_db_open(): %d\n", ret);
ffdb_db_verbose(ffdbctx, 1);
ret = ffdb_db_close(ffdbctx);
printf("ffdb_db_close(): %d\n", ret);
/***/
ffdbctx = ffdb_db_open("/tmp/ffdb2", 64, 64,
FFDB_DB_STAT_READ|FFDB_DB_CREATE_SOFT,
file_mode, dir_mode);
ret = (ffdbctx == 0L);
printf("ffdb_db_open(): %d\n", ret);
ffdb_db_verbose(ffdbctx, 1);
/***/
key.key = "ls2";
key.size = 3;
val.val = "ls2-data";
val.size = 8;
ret = ffdb_rec_open(ffdbctx, &key, O_RDWR|O_CREAT, FFDB_OP_LOCK_EX);
printf("ffdb_rec_open(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
ret = ffdb_rec_put(ffdbctx, &key, &val, 0);
printf("LOCKED: ffdb_put(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
ret = ffdb_rec_close(ffdbctx, &key);
printf("ffdb_rec_close(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
/***/
ret = ffdb_rec_iter(ffdbctx, &key, &val, FFDB_ITER_FIRST|FFDB_ITER_GET);
printf("ffdb_rec_iter(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
if (ret == 1) xerr_errx(1, "done");
printf("iter: key.key=%s, key.size=%d\n", (char*)key.key, (int)key.size);
printf("iter: val.val=%s, val.size=%d\n", (char*)val.val, (int)val.size);
ret = ffdb_rec_iter(ffdbctx, &key, &val, FFDB_ITER_NEXT);
printf("ffdb_rec_iter(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
if (ret == 1) xerr_errx(1, "done");
printf("iter: key.key=%s, key.size=%d\n", (char*)key.key, (int)key.size);
printf("iter: val.val=%s, val.size=%d\n", (char*)val.val, (int)val.size);
ret = ffdb_rec_iter(ffdbctx, &key, &val, FFDB_ITER_DONE);
printf("ffdb_rec_iter(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
if (ret == 1) xerr_errx(1, "done");
key.key = "ls";
key.size = 2;
key2.key = "ll";
key2.size = 2;
ret = ffdb_rec_exists(ffdbctx, &key);
printf("ffdb_rec_exists(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
ret = ffdb_rec_open(ffdbctx, &key, O_RDWR, FFDB_OP_LOCK_EX);
printf("ffdb_rec_open(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
ret = ffdb_rec_open(ffdbctx, &key2, O_RDWR|O_CREAT, FFDB_OP_LOCK_EX);
printf("ffdb_rec_open(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
ret = ffdb_rec_get(ffdbctx, &key, &val, FFDB_OP_REWIND_NO);
printf("ffdb_rec_get(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
ret = ffdb_rec_get(ffdbctx, &key, &val, 0);
printf("ffdb_rec_get(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
printf("size=%d\n", val.size);
printf("val=%s\n", (char*)val.val);
/*
ret = ffdb_rec_lock(ffdbctx, &key, FFDB_OP_LOCK_UN);
printf("ffdb_lock(LOCK_UN): %d\n", ret);
*/
ret = ffdb_rec_put(ffdbctx, &key2, &val, 0);
printf("LOCKED: ffdb_put(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
ret = ffdb_rec_get(ffdbctx, &key, &val, 0);
printf("LOCKED: ffdb_get(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
printf("size=%d\n", val.size);
printf("val=%s\n", (char*)val.val);
ret = ffdb_rec_close(ffdbctx, &key);
printf("ffdb_rec_close(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
ret = ffdb_rec_close(ffdbctx, &key2);
printf("ffdb_rec_close(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
ret = ffdb_db_close(ffdbctx);
printf("ffdb_db_close(): %d\n", ret);
if (ret < 0) xerr_errx(1, "fail");
return 0;
} /* main */
#endif /* FFDB_EXAMPLE */