lvm2/tools/archive.c

/*
 * Copyright (C) 2001 Sistina Software (UK) Limited.
 *
 * This file is released under the GPL.
 */

#include "log.h"
#include "archive.h"
#include "dbg_malloc.h"
#include "format-text.h"
#include "lvm-string.h"
#include "toollib.h"

#include "tools.h"

#include <unistd.h>
#include <limits.h>

static struct {
	int enabled;
	char *dir;
	unsigned int keep_days;
	unsigned int keep_number;

} _archive_params;

int archive_init(const char *dir, unsigned int keep_days, unsigned int keep_min)
{
	_archive_params.dir = NULL;

	if (!*dir)
		return 1;

	if (!create_dir(dir))
		return 0;

	if (!(_archive_params.dir = dbg_strdup(dir))) {
		log_error("Couldn't copy archive directory name.");
		return 0;
	}

	_archive_params.keep_days = keep_days;
	_archive_params.keep_number = keep_min;
	_archive_params.enabled = 1;
	return 1;
}

void archive_exit(void)
{
	if (_archive_params.dir)
		dbg_free(_archive_params.dir);
	memset(&_archive_params, 0, sizeof(_archive_params));
}

void archive_enable(int flag)
{
	_archive_params.enabled = flag;
}

static char *_build_desc(struct pool *mem, const char *line, int before)
{
	size_t len = strlen(line) + 32;
	char *buffer;

	if (!(buffer = pool_zalloc(mem, strlen(line) + 32))) {
		stack;
		return NULL;
	}

	if (snprintf(buffer, len,
		     "Created %s executing '%s'",
		     before ? "*before*" : "*after*", line) < 0) {
		stack;
		return NULL;
	}

	return buffer;
}

static int __archive(struct volume_group *vg)
{
	char *desc;

	if (!(desc = _build_desc(vg->cmd->mem, vg->cmd->cmd_line, 1))) {
		stack;
		return 0;
	}

	return archive_vg(vg, _archive_params.dir, desc,
			  _archive_params.keep_days,
			  _archive_params.keep_number);
}

int archive(struct volume_group *vg)
{
	if (!_archive_params.enabled || !_archive_params.dir)
		return 1;

	if (test_mode()) {
		log_print("Test mode: Skipping archiving of volume group.");
		return 1;
	}

	log_verbose("Archiving volume group \"%s\" metadata.", vg->name);
	if (!__archive(vg)) {
		log_error("Volume group \"%s\" metadata archive failed.",
			  vg->name);
		return 0;
	}

	return 1;
}

int archive_display(struct cmd_context *cmd, const char *vg_name)
{
	return archive_list(cmd, cmd->um, _archive_params.dir, vg_name);
}

static struct {
	int enabled;
	char *dir;

} _backup_params;

int backup_init(const char *dir)
{
	_backup_params.dir = NULL;
	if (!*dir)
		return 1;

	if (!create_dir(dir))
		return 0;

	if (!(_backup_params.dir = dbg_strdup(dir))) {
		log_error("Couldn't copy backup directory name.");
		return 0;
	}

	return 1;
}

void backup_exit(void)
{
	if (_backup_params.dir)
		dbg_free(_backup_params.dir);
	memset(&_backup_params, 0, sizeof(_backup_params));
}

void backup_enable(int flag)
{
	_backup_params.enabled = flag;
}

static int __backup(struct volume_group *vg)
{
	int r;
	struct format_instance *tf;
	char name[PATH_MAX];
	char *desc;
	void *context;

	if (!(desc = _build_desc(vg->cmd->mem, vg->cmd->cmd_line, 0))) {
		stack;
		return 0;
	}

	if (lvm_snprintf(name, sizeof(name), "%s/%s",
			 _backup_params.dir, vg->name) < 0) {
		log_error("Failed to generate volume group metadata backup "
			  "filename.");
		return 0;
	}

	log_verbose("Creating volume group backup \"%s\"", name);

	if (!(context = create_text_context(vg->cmd->fmtt, name, desc)) ||
	    !(tf = vg->cmd->fmtt->ops->create_instance(vg->cmd->fmtt, NULL,
						       context))) {
		stack;
		return 0;
	}

	if (!(r = tf->fmt->ops->vg_write(tf, vg, context)) ||
	    !(r = tf->fmt->ops->vg_commit(tf, vg, context)))
		stack;

	tf->fmt->ops->destroy_instance(tf);

	return r;
}

int backup(struct volume_group *vg)
{
	if (!_backup_params.enabled || !_backup_params.dir) {
		log_print("WARNING: This metadata update is NOT backed up");
		return 1;
	}

	if (test_mode()) {
		log_print("Test mode: Skipping volume group backup.");
		return 1;
	}

	if (!__backup(vg)) {
		log_error("Backup of volume group %s metadata failed.",
			  vg->name);
		return 0;
	}

	return 1;
}

int backup_remove(const char *vg_name)
{
	char path[PATH_MAX];

	if (lvm_snprintf(path, sizeof(path), "%s/%s",
			 _backup_params.dir, vg_name) < 0) {
		log_err("Failed to generate backup filename (for removal).");
		return 0;
	}

	/*
	 * Let this fail silently.
	 */
	unlink(path);
	return 1;
}

static struct volume_group *_read_vg(struct cmd_context *cmd,
				     const char *vg_name, const char *file)
{
	struct volume_group *vg;
	struct format_instance *tf;
	void *context;

	if (!(context = create_text_context(vg->cmd->fmtt, file,
					    cmd->cmd_line)) ||
	    !(tf = vg->cmd->fmtt->ops->create_instance(cmd->fmtt, NULL,
						       context))) {
		log_error("Couldn't create text format object.");
		return NULL;
	}

	if (!(vg = tf->fmt->ops->vg_read(tf, vg_name, context)))
		stack;

	tf->fmt->ops->destroy_instance(tf);
	return vg;
}

int backup_restore_from_file(struct cmd_context *cmd, const char *vg_name,
			     const char *file)
{
	struct volume_group *vg;

	/*
	 * Read in the volume group.
	 */
	if (!(vg = _read_vg(cmd, vg_name, file))) {
		stack;
		return 0;
	}

	/*
	 * Check that those pv's referenced in the backup are
	 * currently orphans or members of the vg.s
	 */
	/*
	 * FIXME: waiting for label code.
	 */

	/*
	 * Write the vg.
	 */

	/* FIXME How do I find what format to write out the VG in? */
	/* Must store the format type inside the backup? */
	if (!(vg->fid = cmd->fmt1->ops->create_instance(cmd->fmt1, NULL, NULL))) {
		log_error("Failed to allocate format1 instance");
		return 0;
	}

	if (!vg_write(vg)) {
		stack;
		return 0;
	}

	return 1;
}

int backup_restore(struct cmd_context *cmd, const char *vg_name)
{
	char path[PATH_MAX];

	if (lvm_snprintf(path, sizeof(path), "%s/%s",
			 _backup_params.dir, vg_name) < 0) {
		log_err("Failed to generate backup filename (for restore).");
		return 0;
	}

	return backup_restore_from_file(cmd, vg_name, path);
}