serval-dna/conf.c
Andrew Bettison 6201b97fa3 Shorten trigger names for OS X
Trigger names cannot exceed 11 characters on OS X, so the new "config_change" trigger
has been renamed to "conf_change" and the "config_change_log" trigger has been renamed
to "conf_log".
2016-10-25 09:34:32 +10:30

292 lines
8.4 KiB
C

/*
Serval DNA configuration
Copyright (C) 2012 Serval Project Inc.
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 <stdio.h>
#include <sys/stat.h>
#include <ctype.h>
#include <time.h>
#include <inttypes.h> // for PRIu64 on Android
#include "conf.h"
#include "instance.h"
#include "log.h"
#include "debug.h"
#include "str.h"
#include "mem.h"
#include "os.h"
#define CONFFILE_NAME "serval.conf"
struct cf_om_node *cf_om_root = NULL;
static __thread struct file_meta conffile_meta = FILE_META_UNKNOWN;
__thread int cf_initialised = 0;
__thread int cf_limbo = 1;
__thread struct config_main config;
static __thread struct file_meta config_meta = FILE_META_UNKNOWN;
static const char *conffile_path()
{
static char path[1024] = "";
if (!path[0] && !FORMF_SERVAL_ETC_PATH(path, CONFFILE_NAME))
abort();
return path;
}
static int reload(const char *path, int *resultp)
{
DEBUGF(config, " file path=%s", alloca_str_toprint(path));
struct file_meta meta;
if (get_file_meta(path, &meta) == -1)
return -1;
DEBUGF(config, " file meta=%s", alloca_file_meta(&meta));
DEBUGF(config, "conffile_meta=%s", alloca_file_meta(&conffile_meta));
if (cmp_file_meta(&meta, &conffile_meta) == 0)
return 0;
if (conffile_meta.mtime.tv_sec != -1)
INFOF("config file %s -- detected new version", path);
char *buf = NULL;
if (meta.mtime.tv_sec == -1) {
WARNF("config file %s does not exist -- using all defaults", path);
} else if (meta.size > CONFIG_FILE_MAX_SIZE) {
WHYF("config file %s is too big (%ju bytes exceeds limit %d)", path, (uintmax_t)meta.size, CONFIG_FILE_MAX_SIZE);
return -1;
} else if (meta.size <= 0) {
WARNF("config file %s is zero size -- using all defaults", path);
} else {
FILE *f = fopen(path, "r");
if (f == NULL) {
WHYF_perror("fopen(%s)", path);
return -1;
}
if ((buf = emalloc(meta.size)) == NULL) {
fclose(f);
return -1;
}
if (fread(buf, meta.size, 1, f) != 1) {
if (ferror(f))
WHYF_perror("fread(%s, %"PRIu64")", path, (uint64_t) meta.size);
else
WHYF("fread(%s, %"PRIu64") hit EOF", path, (uint64_t) meta.size);
free(buf);
fclose(f);
return -1;
}
if (fclose(f) == EOF) {
WHYF_perror("fclose(%s)", path);
free(buf);
return -1;
}
DEBUGF(config, "config file %s successfully read %ld bytes", path, (long) meta.size);
}
conffile_meta = meta;
DEBUGF(config, "set conffile_meta=%s", alloca_file_meta(&conffile_meta));
struct cf_om_node *new_root = NULL;
*resultp = cf_om_parse(path, buf, meta.size, &new_root);
free(buf);
if (*resultp == CFERROR)
return -1;
cf_om_free_node(&cf_om_root);
cf_om_root = new_root;
return 1;
}
int cf_om_reload()
{
int result;
return reload(conffile_path(), &result);
}
int cf_om_load()
{
conffile_meta = FILE_META_UNKNOWN;
return cf_om_reload();
}
int cf_om_save()
{
if (cf_om_root) {
const char *path = conffile_path();
struct file_meta meta;
if (get_file_meta(path, &meta) == -1)
return -1;
char tempfile[1024];
FILE *outf = NULL;
if (!FORMF_SERVAL_ETC_PATH(tempfile, CONFFILE_NAME ".temp"))
return -1;
if ((outf = fopen(tempfile, "w")) == NULL)
return WHYF_perror("fopen(%s, \"w\")", tempfile);
struct cf_om_iterator it;
for (cf_om_iter_start(&it, cf_om_root); it.node; cf_om_iter_next(&it))
if (it.node->text)
fprintf(outf, "%s=%s\n", it.node->fullkey, it.node->text);
if (fclose(outf) == EOF)
return WHYF_perror("fclose(%s)", tempfile);
// rename(2) is atomic, so no other process will read a half-written file.
if (rename(tempfile, path)) {
WHYF_perror("rename(%s, %s)", tempfile, path);
unlink(tempfile);
return -1;
}
struct file_meta newmeta;
int r = alter_file_meta(path, &meta, &newmeta);
if (r == -1)
return -1;
if (r)
INFOF("wrote %s; set mtime=%s", path, alloca_time_t(newmeta.mtime.tv_sec));
else if (cmp_file_meta(&meta, &newmeta) == 0)
WARNF("wrote %s; mtime not altered", path);
else
INFOF("wrote %s", path);
conffile_meta = newmeta;
DEBUGF(config, "set conffile_meta=%s", alloca_file_meta(&conffile_meta));
}
return 0;
}
int cf_init()
{
if (!cf_initialised) {
memset(&config, 0, sizeof config);
if (cf_dfl_config_main(&config) == CFERROR)
return -1;
conffile_meta = config_meta = FILE_META_UNKNOWN;
cf_limbo = 1;
cf_initialised = 1;
}
return 0;
}
/* (Re-)load and parse the configuration file.
*
* The 'strict' flag controls whether this function will load a defective config file. If nonzero,
* then it will not load a defective file, but will log an error and return -1. If zero, then it
* will load a defective file and use the 'permissive' flag to decide what to log and return.
*
* The 'permissive' flag only applies if 'strict' is zero, and determines how this function deals
* with a loaded defective config file. If 'permissive' is zero, then it logs an error and returns
* -1. If nonzero, then it logs a warning and returns 0.
*
* @author Andrew Bettison <andrew@servalproject.com>
*/
static int reload_and_parse(int permissive, int strict)
{
int result = CFOK;
int changed = 0;
assert(cf_initialised);
if (cf_limbo)
result = cf_dfl_config_main(&config);
if (result == CFOK || result == CFEMPTY) {
if (reload(conffile_path(), &result) == -1)
result = CFERROR;
else if (!cf_limbo && cmp_file_meta(&conffile_meta, &config_meta) == 0)
return 0;
else {
config_meta = conffile_meta;
if (result == CFOK || result == CFEMPTY) {
struct config_main new_config;
int update = 0;
memset(&new_config, 0, sizeof new_config);
result = cf_dfl_config_main(&new_config);
if (result == CFOK || result == CFEMPTY) {
result = cf_om_root ? cf_opt_config_main(&new_config, cf_om_root) : CFEMPTY;
if (result == CFOK || result == CFEMPTY) {
result = CFOK;
update = 1;
} else if (result != CFERROR && !strict) {
result &= ~CFEMPTY; // don't log "empty" as a problem
update = 1;
}
}
if (update && cf_cmp_config_main(&config, &new_config) != 0) {
config = new_config;
changed = 1;
}
}
}
}
int ret = changed;
if (result != CFOK) {
strbuf b = strbuf_alloca(180);
strbuf_cf_flag_reason(b, result);
if (strict)
ret = WHYF("defective config file %s not loaded -- %s", conffile_path(), strbuf_str(b));
else {
if (!permissive)
ret = WHYF("config file %s loaded despite defects -- %s", conffile_path(), strbuf_str(b));
else
WARNF("config file %s loaded despite defects -- %s", conffile_path(), strbuf_str(b));
}
}
cf_limbo = 0; // let log messages out
logFlush();
if (changed) {
CALL_TRIGGER(conf_log);
CALL_TRIGGER(conf_change);
}
return ret;
}
// Put a dummy no-op trigger callback into the "config_change" and "config_log" trigger sections,
// otherwise if no other object provides one, the link will fail with errors like:
// undefined reference to `__start_tr_config_change'
// undefined reference to `__stop_tr_config_change'
static void __dummy_on_config_log();
DEFINE_TRIGGER(conf_log, __dummy_on_config_log);
static void __dummy_on_config_log() {}
static void __dummy_on_config_change();
DEFINE_TRIGGER(conf_change, __dummy_on_config_change);
static void __dummy_on_config_change() {}
// The configuration API entry points.
int cf_load()
{
conffile_meta = config_meta = FILE_META_UNKNOWN;
return reload_and_parse(0, 0);
}
int cf_load_strict()
{
conffile_meta = config_meta = FILE_META_UNKNOWN;
return reload_and_parse(0, 1);
}
int cf_load_permissive()
{
conffile_meta = config_meta = FILE_META_UNKNOWN;
return reload_and_parse(1, 0);
}
int cf_reload()
{
return reload_and_parse(0, 0);
}
int cf_reload_strict()
{
return reload_and_parse(0, 1);
}
int cf_reload_permissive()
{
return reload_and_parse(1, 0);
}