1
0
mirror of git://sourceware.org/git/lvm2.git synced 2024-12-25 01:34:38 +03:00
lvm2/liblvm/lvm_base.c
David Teigland 7fd4119d24 liblvm: allow config settings to be read without full lvm cmd
A program may be using liblvm2app for simply checking a config
setting in lvm.conf.  In this case, a full lvm context is not
needed, only cmd->cft (which are the config settings read from
lvm.conf).

lvm_config_find_bool() can now be passed a NULL lvm context
in which case it will only create cmd->cft, check the config
setting asked for, and destroy the cmd.
2016-05-18 09:04:25 -05:00

217 lines
5.1 KiB
C

/*
* Copyright (C) 2008,2009 Red Hat, Inc. All rights reserved.
*
* This file is part of LVM2.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU Lesser General Public License v.2.1.
*
* You should have received a copy of the GNU Lesser 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 "lib.h"
#include "toolcontext.h"
#include "locking.h"
#include "lvm-version.h"
#include "metadata-exported.h"
#include "lvm2app.h"
#include "lvm_misc.h"
const char *lvm_library_get_version(void)
{
return LVM_VERSION;
}
static lvm_t _lvm_init(const char *system_dir)
{
struct cmd_context *cmd;
/* FIXME: logging bound to handle
*/
if (!udev_init_library_context())
stack;
/*
* It's not necessary to use name mangling for LVM:
* - the character set used for VG-LV names is subset of udev character set
* - when we check other devices (e.g. device_is_usable fn), we use major:minor, not dm names
*/
dm_set_name_mangling_mode(DM_STRING_MANGLING_NONE);
/* create context */
/* FIXME: split create_toolcontext */
/* FIXME: make all globals configurable */
cmd = create_toolcontext(0, system_dir, 0, 0, 1, 1);
if (!cmd)
return NULL;
/*
* FIXME: if an non memory error occured, return the cmd (maybe some
* cleanup needed).
*/
/* initialization from lvm_run_command */
init_error_message_produced(0);
/* FIXME: locking_type config option needed? */
/* initialize locking */
if (!init_locking(-1, cmd, 0)) {
/* FIXME: use EAGAIN as error code here */
lvm_quit((lvm_t) cmd);
return NULL;
}
/*
* FIXME: Use cmd->cmd_line as audit trail for liblvm calls. Used in
* archive() call. Possible example:
* cmd_line = "lvm_vg_create: vg1\nlvm_vg_extend vg1 /dev/sda1\n"
*/
cmd->cmd_line = "liblvm";
/*
* Turn off writing to stdout/stderr.
* FIXME Fix lib/ to support a non-interactive mode instead.
*/
log_suppress(1);
return (lvm_t) cmd;
}
lvm_t lvm_init(const char *system_dir)
{
lvm_t h = NULL;
struct saved_env e = store_user_env(NULL);
h = _lvm_init(system_dir);
restore_user_env(&e);
return h;
}
void lvm_quit(lvm_t libh)
{
struct saved_env e = store_user_env((struct cmd_context *)libh);
fin_locking();
destroy_toolcontext((struct cmd_context *)libh);
udev_fin_library_context();
restore_user_env(&e);
}
int lvm_config_reload(lvm_t libh)
{
int rc = 0;
/* FIXME: re-init locking needed here? */
struct saved_env e = store_user_env((struct cmd_context *)libh);
if (!refresh_toolcontext((struct cmd_context *)libh))
rc = -1;
restore_user_env(&e);
return rc;
}
/*
* FIXME: submit a patch to document the --config option
*/
int lvm_config_override(lvm_t libh, const char *config_settings)
{
int rc = 0;
struct cmd_context *cmd = (struct cmd_context *)libh;
struct saved_env e = store_user_env((struct cmd_context *)libh);
if (!override_config_tree_from_string(cmd, config_settings))
rc = -1;
restore_user_env(&e);
return rc;
}
/*
* When full lvm connection is not being used, libh can be NULL
* and this command will internally create a single-use, light-weight
* cmd struct that only has cmd->cft populated from lvm.conf.
*/
int lvm_config_find_bool(lvm_t libh, const char *config_path, int fail)
{
int rc = 0;
struct cmd_context *cmd;
struct saved_env e;
if (libh) {
cmd = (struct cmd_context *)libh;
e = store_user_env((struct cmd_context *)libh);
} else {
if (!(cmd = create_config_context()))
return 0;
}
rc = dm_config_tree_find_bool(cmd->cft, config_path, fail);
if (libh)
restore_user_env(&e);
else
destroy_config_context(cmd);
return rc;
}
int lvm_errno(lvm_t libh)
{
int rc;
struct saved_env e = store_user_env((struct cmd_context *)libh);
rc = stored_errno();
restore_user_env(&e);
return rc;
}
const char *lvm_errmsg(lvm_t libh)
{
const char *rc = NULL;
struct cmd_context *cmd = (struct cmd_context *)libh;
struct saved_env e = store_user_env((struct cmd_context *)libh);
const char *msg = stored_errmsg_with_clear();
if (msg) {
rc = dm_pool_strdup(cmd->mem, msg);
free((void *)msg);
}
restore_user_env(&e);
return rc;
}
const char *lvm_vgname_from_pvid(lvm_t libh, const char *pvid)
{
const char *rc = NULL;
struct cmd_context *cmd = (struct cmd_context *)libh;
struct id id;
struct saved_env e = store_user_env((struct cmd_context *)libh);
if (id_read_format(&id, pvid)) {
rc = find_vgname_from_pvid(cmd, (char *)id.uuid);
} else {
log_error(INTERNAL_ERROR "Unable to convert uuid");
}
restore_user_env(&e);
return rc;
}
const char *lvm_vgname_from_device(lvm_t libh, const char *device)
{
const char *rc = NULL;
struct cmd_context *cmd = (struct cmd_context *)libh;
struct saved_env e = store_user_env(cmd);
rc = find_vgname_from_pvname(cmd, device);
restore_user_env(&e);
return rc;
}
/*
* No context to work with, so no ability to save off and restore env is not
* available and is not needed.
*/
float lvm_percent_to_float(percent_t v)
{
return dm_percent_to_float(v);
}