+++ /dev/null
-/* Cumulus: Smart Filesystem Backup to Dumb Servers
- *
- * Copyright (C) 2006-2008 The Regents of the University of California
- * Written by Michael Vrable <mvrable@cs.ucsd.edu>
- *
- * 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.
- */
-
-/* Main entry point for LBS. Contains logic for traversing the filesystem and
- * constructing a backup. */
-
-#include <dirent.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <getopt.h>
-#include <grp.h>
-#include <pwd.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/stat.h>
-#include <sys/sysmacros.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <unistd.h>
-
-#include <algorithm>
-#include <fstream>
-#include <iostream>
-#include <list>
-#include <set>
-#include <sstream>
-#include <string>
-#include <vector>
-
-#include "localdb.h"
-#include "metadata.h"
-#include "remote.h"
-#include "store.h"
-#include "sha1.h"
-#include "subfile.h"
-#include "util.h"
-
-using std::list;
-using std::string;
-using std::vector;
-using std::ostream;
-
-/* Version information. This will be filled in by the Makefile. */
-#ifndef CUMULUS_VERSION
-#define CUMULUS_VERSION Unknown
-#endif
-#define CUMULUS_STRINGIFY(s) CUMULUS_STRINGIFY2(s)
-#define CUMULUS_STRINGIFY2(s) #s
-static const char cumulus_version[] = CUMULUS_STRINGIFY(CUMULUS_VERSION);
-
-static RemoteStore *remote = NULL;
-static TarSegmentStore *tss = NULL;
-static MetadataWriter *metawriter = NULL;
-
-/* Buffer for holding a single block of data read from a file. */
-static const size_t LBS_BLOCK_SIZE = 1024 * 1024;
-static char *block_buf;
-
-/* Local database, which tracks objects written in this and previous
- * invocations to help in creating incremental snapshots. */
-LocalDb *db;
-
-/* Keep track of all segments which are needed to reconstruct the snapshot. */
-std::set<string> segment_list;
-
-/* Snapshot intent: 1=daily, 7=weekly, etc. This is not used directly, but is
- * stored in the local database and can help guide segment cleaning and
- * snapshot expiration policies. */
-double snapshot_intent = 1.0;
-
-/* Selection of files to include/exclude in the snapshot. */
-std::list<string> includes; // Paths in which files should be saved
-std::list<string> excludes; // Paths which will not be saved
-std::list<string> excluded_names; // Directories which will not be saved
-std::list<string> searches; // Directories we don't want to save, but
- // do want to descend searching for data
- // in included paths
-
-bool relative_paths = true;
-
-bool flag_rebuild_statcache = false;
-
-/* Whether verbose output is enabled. */
-bool verbose = false;
-
-/* Ensure that the given segment is listed as a dependency of the current
- * snapshot. */
-void add_segment(const string& segment)
-{
- segment_list.insert(segment);
-}
-
-/* Read data from a file descriptor and return the amount of data read. A
- * short read (less than the requested size) will only occur if end-of-file is
- * hit. */
-ssize_t file_read(int fd, char *buf, size_t maxlen)
-{
- size_t bytes_read = 0;
-
- while (true) {
- ssize_t res = read(fd, buf, maxlen);
- if (res < 0) {
- if (errno == EINTR)
- continue;
- fprintf(stderr, "error reading file: %m\n");
- return -1;
- } else if (res == 0) {
- break;
- } else {
- bytes_read += res;
- buf += res;
- maxlen -= res;
- }
- }
-
- return bytes_read;
-}
-
-/* Read the contents of a file (specified by an open file descriptor) and copy
- * the data to the store. Returns the size of the file (number of bytes
- * dumped), or -1 on error. */
-int64_t dumpfile(int fd, dictionary &file_info, const string &path,
- struct stat& stat_buf)
-{
- int64_t size = 0;
- list<string> object_list;
- const char *status = NULL; /* Status indicator printed out */
-
- /* Look up this file in the old stat cache, if we can. If the stat
- * information indicates that the file has not changed, do not bother
- * re-reading the entire contents. Even if the information has been
- * changed, we can use the list of old blocks in the search for a sub-block
- * incremental representation. */
- bool cached = false;
- list<ObjectReference> old_blocks;
-
- bool found = metawriter->find(path);
- if (found)
- old_blocks = metawriter->get_blocks();
-
- if (found
- && !flag_rebuild_statcache
- && metawriter->is_unchanged(&stat_buf)) {
- cached = true;
-
- /* If any of the blocks in the object have been expired, then we should
- * fall back to fully reading in the file. */
- for (list<ObjectReference>::const_iterator i = old_blocks.begin();
- i != old_blocks.end(); ++i) {
- const ObjectReference &ref = *i;
- if (!db->IsAvailable(ref)) {
- cached = false;
- status = "repack";
- break;
- }
- }
-
- /* If everything looks okay, use the cached information */
- if (cached) {
- file_info["checksum"] = metawriter->get_checksum();
- for (list<ObjectReference>::const_iterator i = old_blocks.begin();
- i != old_blocks.end(); ++i) {
- const ObjectReference &ref = *i;
- object_list.push_back(ref.to_string());
- if (ref.is_normal())
- add_segment(ref.get_segment());
- db->UseObject(ref);
- }
- size = stat_buf.st_size;
- }
- }
-
- /* If the file is new or changed, we must read in the contents a block at a
- * time. */
- if (!cached) {
- SHA1Checksum hash;
- Subfile subfile(db);
- subfile.load_old_blocks(old_blocks);
-
- while (true) {
- ssize_t bytes = file_read(fd, block_buf, LBS_BLOCK_SIZE);
- if (bytes == 0)
- break;
- if (bytes < 0) {
- fprintf(stderr, "Backup contents for %s may be incorrect\n",
- path.c_str());
- break;
- }
-
- hash.process(block_buf, bytes);
-
- // Sparse file processing: if we read a block of all zeroes, encode
- // that explicitly.
- bool all_zero = true;
- for (int i = 0; i < bytes; i++) {
- if (block_buf[i] != 0) {
- all_zero = false;
- break;
- }
- }
-
- // Either find a copy of this block in an already-existing segment,
- // or index it so it can be re-used in the future
- double block_age = 0.0;
- ObjectReference ref;
-
- SHA1Checksum block_hash;
- block_hash.process(block_buf, bytes);
- string block_csum = block_hash.checksum_str();
-
- if (all_zero) {
- ref = ObjectReference(ObjectReference::REF_ZERO);
- ref.set_range(0, bytes);
- } else {
- ref = db->FindObject(block_csum, bytes);
- }
-
- list<ObjectReference> refs;
-
- // Store a copy of the object if one does not yet exist
- if (ref.is_null()) {
- LbsObject *o = new LbsObject;
- int object_group;
-
- /* We might still have seen this checksum before, if the object
- * was stored at some time in the past, but we have decided to
- * clean the segment the object was originally stored in
- * (FindObject will not return such objects). When rewriting
- * the object contents, put it in a separate group, so that old
- * objects get grouped together. The hope is that these old
- * objects will continue to be used in the future, and we
- * obtain segments which will continue to be well-utilized.
- * Additionally, keep track of the age of the data by looking
- * up the age of the block which was expired and using that
- * instead of the current time. */
- if (db->IsOldObject(block_csum, bytes,
- &block_age, &object_group)) {
- if (object_group == 0) {
- o->set_group("data");
- } else {
- char group[32];
- sprintf(group, "compacted-%d", object_group);
- o->set_group(group);
- }
- if (status == NULL)
- status = "partial";
- } else {
- o->set_group("data");
- status = "new";
- }
-
- subfile.analyze_new_block(block_buf, bytes);
- refs = subfile.create_incremental(tss, o, block_age);
- } else {
- if (flag_rebuild_statcache && ref.is_normal()) {
- subfile.analyze_new_block(block_buf, bytes);
- subfile.store_analyzed_signatures(ref);
- }
- refs.push_back(ref);
- }
-
- while (!refs.empty()) {
- ref = refs.front(); refs.pop_front();
- object_list.push_back(ref.to_string());
- if (ref.is_normal())
- add_segment(ref.get_segment());
- db->UseObject(ref);
- }
- size += bytes;
-
- if (status == NULL)
- status = "old";
- }
-
- file_info["checksum"] = hash.checksum_str();
- }
-
- // Sanity check: if we are rebuilding the statcache, but the file looks
- // like it hasn't changed, then the newly-computed checksum should match
- // the checksum in the statcache. If not, we have possible disk corruption
- // and report a warning.
- if (flag_rebuild_statcache) {
- if (found
- && metawriter->is_unchanged(&stat_buf)
- && file_info["checksum"] != metawriter->get_checksum()) {
- fprintf(stderr,
- "Warning: Checksum for %s does not match expected value\n"
- " expected: %s\n"
- " actual: %s\n",
- path.c_str(),
- metawriter->get_checksum().c_str(),
- file_info["checksum"].c_str());
- }
- }
-
- if (verbose && status != NULL)
- printf(" [%s]\n", status);
-
- string blocklist = "";
- for (list<string>::iterator i = object_list.begin();
- i != object_list.end(); ++i) {
- if (i != object_list.begin())
- blocklist += "\n ";
- blocklist += *i;
- }
- file_info["data"] = blocklist;
-
- return size;
-}
-
-/* Dump a specified filesystem object (file, directory, etc.) based on its
- * inode information. If the object is a regular file, an open filehandle is
- * provided. */
-void dump_inode(const string& path, // Path within snapshot
- const string& fullpath, // Path to object in filesystem
- struct stat& stat_buf, // Results of stat() call
- int fd) // Open filehandle if regular file
-{
- char *buf;
- dictionary file_info;
- int64_t file_size;
- ssize_t len;
-
- if (verbose)
- printf("%s\n", path.c_str());
- metawriter->find(path);
-
- file_info["name"] = uri_encode(path);
- file_info["mode"] = encode_int(stat_buf.st_mode & 07777, 8);
- file_info["ctime"] = encode_int(stat_buf.st_ctime);
- file_info["mtime"] = encode_int(stat_buf.st_mtime);
- file_info["user"] = encode_int(stat_buf.st_uid);
- file_info["group"] = encode_int(stat_buf.st_gid);
-
- time_t now = time(NULL);
- if (now - stat_buf.st_ctime < 30 || now - stat_buf.st_mtime < 30)
- if ((stat_buf.st_mode & S_IFMT) != S_IFDIR)
- file_info["volatile"] = "1";
-
- struct passwd *pwd = getpwuid(stat_buf.st_uid);
- if (pwd != NULL && pwd->pw_name != NULL) {
- file_info["user"] += " (" + uri_encode(pwd->pw_name) + ")";
- }
-
- struct group *grp = getgrgid(stat_buf.st_gid);
- if (grp != NULL && grp->gr_name != NULL) {
- file_info["group"] += " (" + uri_encode(grp->gr_name) + ")";
- }
-
- if (stat_buf.st_nlink > 1 && (stat_buf.st_mode & S_IFMT) != S_IFDIR) {
- file_info["links"] = encode_int(stat_buf.st_nlink);
- }
-
- file_info["inode"] = encode_int(major(stat_buf.st_dev))
- + "/" + encode_int(minor(stat_buf.st_dev))
- + "/" + encode_int(stat_buf.st_ino);
-
- char inode_type;
-
- switch (stat_buf.st_mode & S_IFMT) {
- case S_IFIFO:
- inode_type = 'p';
- break;
- case S_IFSOCK:
- inode_type = 's';
- break;
- case S_IFBLK:
- case S_IFCHR:
- inode_type = ((stat_buf.st_mode & S_IFMT) == S_IFBLK) ? 'b' : 'c';
- file_info["device"] = encode_int(major(stat_buf.st_rdev))
- + "/" + encode_int(minor(stat_buf.st_rdev));
- break;
- case S_IFLNK:
- inode_type = 'l';
-
- /* Use the reported file size to allocate a buffer large enough to read
- * the symlink. Allocate slightly more space, so that we ask for more
- * bytes than we expect and so check for truncation. */
- buf = new char[stat_buf.st_size + 2];
- len = readlink(fullpath.c_str(), buf, stat_buf.st_size + 1);
- if (len < 0) {
- fprintf(stderr, "error reading symlink: %m\n");
- } else if (len <= stat_buf.st_size) {
- buf[len] = '\0';
- file_info["target"] = uri_encode(buf);
- } else if (len > stat_buf.st_size) {
- fprintf(stderr, "error reading symlink: name truncated\n");
- }
-
- delete[] buf;
- break;
- case S_IFREG:
- inode_type = 'f';
-
- file_size = dumpfile(fd, file_info, path, stat_buf);
- file_info["size"] = encode_int(file_size);
-
- if (file_size < 0)
- return; // error occurred; do not dump file
-
- if (file_size != stat_buf.st_size) {
- fprintf(stderr, "Warning: Size of %s changed during reading\n",
- path.c_str());
- file_info["volatile"] = "1";
- }
-
- break;
- case S_IFDIR:
- inode_type = 'd';
- break;
-
- default:
- fprintf(stderr, "Unknown inode type: mode=%x\n", stat_buf.st_mode);
- return;
- }
-
- file_info["type"] = string(1, inode_type);
-
- metawriter->add(file_info);
-}
-
-void scanfile(const string& path, bool include)
-{
- int fd = -1;
- long flags;
- struct stat stat_buf;
- list<string> refs;
-
- string true_path;
- if (relative_paths)
- true_path = path;
- else
- true_path = "/" + path;
-
- // Set to true if we should scan through the contents of this directory,
- // but not actually back files up
- bool scan_only = false;
-
- // Check this file against the include/exclude list to see if it should be
- // considered
- for (list<string>::iterator i = includes.begin();
- i != includes.end(); ++i) {
- if (path == *i) {
- include = true;
- }
- }
-
- for (list<string>::iterator i = excludes.begin();
- i != excludes.end(); ++i) {
- if (path == *i) {
- include = false;
- }
- }
-
- if (excluded_names.size() > 0) {
- std::string name = path;
- std::string::size_type last_slash = name.rfind('/');
- if (last_slash != std::string::npos) {
- name.replace(0, last_slash + 1, "");
- }
-
- for (list<string>::iterator i = excluded_names.begin();
- i != excluded_names.end(); ++i) {
- if (name == *i) {
- include = false;
- }
- }
- }
-
- for (list<string>::iterator i = searches.begin();
- i != searches.end(); ++i) {
- if (path == *i) {
- scan_only = true;
- }
- }
-
- if (!include && !scan_only)
- return;
-
- if (lstat(true_path.c_str(), &stat_buf) < 0) {
- fprintf(stderr, "lstat(%s): %m\n", path.c_str());
- return;
- }
-
- if ((stat_buf.st_mode & S_IFMT) == S_IFREG) {
- /* Be paranoid when opening the file. We have no guarantee that the
- * file was not replaced between the stat() call above and the open()
- * call below, so we might not even be opening a regular file. We
- * supply flags to open to to guard against various conditions before
- * we can perform an lstat to check that the file is still a regular
- * file:
- * - O_NOFOLLOW: in the event the file was replaced by a symlink
- * - O_NONBLOCK: prevents open() from blocking if the file was
- * replaced by a fifo
- * We also add in O_NOATIME, since this may reduce disk writes (for
- * inode updates). However, O_NOATIME may result in EPERM, so if the
- * initial open fails, try again without O_NOATIME. */
- fd = open(true_path.c_str(), O_RDONLY|O_NOATIME|O_NOFOLLOW|O_NONBLOCK);
- if (fd < 0) {
- fd = open(true_path.c_str(), O_RDONLY|O_NOFOLLOW|O_NONBLOCK);
- }
- if (fd < 0) {
- fprintf(stderr, "Unable to open file %s: %m\n", path.c_str());
- return;
- }
-
- /* Drop the use of the O_NONBLOCK flag; we only wanted that for file
- * open. */
- flags = fcntl(fd, F_GETFL);
- fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
-
- /* Perform the stat call again, and check that we still have a regular
- * file. */
- if (fstat(fd, &stat_buf) < 0) {
- fprintf(stderr, "fstat: %m\n");
- close(fd);
- return;
- }
-
- if ((stat_buf.st_mode & S_IFMT) != S_IFREG) {
- fprintf(stderr, "file is no longer a regular file!\n");
- close(fd);
- return;
- }
- }
-
- dump_inode(path, true_path, stat_buf, fd);
-
- if (fd >= 0)
- close(fd);
-
- // If we hit a directory, now that we've written the directory itself,
- // recursively scan the directory.
- if ((stat_buf.st_mode & S_IFMT) == S_IFDIR) {
- DIR *dir = opendir(true_path.c_str());
-
- if (dir == NULL) {
- fprintf(stderr, "Error: %m\n");
- return;
- }
-
- struct dirent *ent;
- vector<string> contents;
- while ((ent = readdir(dir)) != NULL) {
- string filename(ent->d_name);
- if (filename == "." || filename == "..")
- continue;
- contents.push_back(filename);
- }
-
- closedir(dir);
-
- sort(contents.begin(), contents.end());
-
- for (vector<string>::iterator i = contents.begin();
- i != contents.end(); ++i) {
- const string& filename = *i;
- if (path == ".")
- scanfile(filename, include);
- else
- scanfile(path + "/" + filename, include);
- }
- }
-}
-
-/* Include the specified file path in the backups. Append the path to the
- * includes list, and to ensure that we actually see the path when scanning the
- * directory tree, add all the parent directories to the search list, which
- * means we will scan through the directory listing even if the files
- * themselves are excluded from being backed up. */
-void add_include(const char *path)
-{
- /* Was an absolute path specified? If so, we'll need to start scanning
- * from the root directory. Make sure that the user was consistent in
- * providing either all relative paths or all absolute paths. */
- if (path[0] == '/') {
- if (includes.size() > 0 && relative_paths == true) {
- fprintf(stderr,
- "Error: Cannot mix relative and absolute paths!\n");
- exit(1);
- }
-
- relative_paths = false;
-
- // Skip over leading '/'
- path++;
- } else if (relative_paths == false && path[0] != '/') {
- fprintf(stderr, "Error: Cannot mix relative and absolute paths!\n");
- exit(1);
- }
-
- includes.push_back(path);
-
- /* Split the specified path into directory components, and ensure that we
- * descend into all the directories along the path. */
- const char *slash = path;
-
- if (path[0] == '\0')
- return;
-
- while ((slash = strchr(slash + 1, '/')) != NULL) {
- string component(path, slash - path);
- searches.push_back(component);
- }
-}
-
-void usage(const char *program)
-{
- fprintf(
- stderr,
- "Cumulus %s\n\n"
- "Usage: %s [OPTION]... --dest=DEST PATHS...\n"
- "Produce backup snapshot of files in SOURCE and store to DEST.\n"
- "\n"
- "Options:\n"
- " --dest=PATH path where backup is to be written\n"
- " --upload-script=COMMAND\n"
- " program to invoke for each backup file generated\n"
- " --exclude=PATH exclude files in PATH from snapshot\n"
- " --exclude-name=NAME exclude files called NAME from snapshot\n"
- " --localdb=PATH local backup metadata is stored in PATH\n"
- " --tmpdir=PATH path for temporarily storing backup files\n"
- " (defaults to TMPDIR environment variable or /tmp)\n"
- " --filter=COMMAND program through which to filter segment data\n"
- " (defaults to \"bzip2 -c\")\n"
- " --filter-extension=EXT\n"
- " string to append to segment files\n"
- " (defaults to \".bz2\")\n"
- " --signature-filter=COMMAND\n"
- " program though which to filter descriptor\n"
- " --scheme=NAME optional name for this snapshot\n"
- " --intent=FLOAT intended backup type: 1=daily, 7=weekly, ...\n"
- " (defaults to \"1\")\n"
- " --full-metadata do not re-use metadata from previous backups\n"
- " --rebuild-statcache re-read all file data to verify statcache\n"
- " -v --verbose list files as they are backed up\n"
- "\n"
- "Exactly one of --dest or --upload-script must be specified.\n",
- cumulus_version, program
- );
-}
-
-int main(int argc, char *argv[])
-{
- string backup_dest = "", backup_script = "";
- string localdb_dir = "";
- string backup_scheme = "";
- string signature_filter = "";
-
- string tmp_dir = "/tmp";
- if (getenv("TMPDIR") != NULL)
- tmp_dir = getenv("TMPDIR");
-
- while (1) {
- static struct option long_options[] = {
- {"localdb", 1, 0, 0}, // 0
- {"exclude", 1, 0, 0}, // 1
- {"filter", 1, 0, 0}, // 2
- {"filter-extension", 1, 0, 0}, // 3
- {"dest", 1, 0, 0}, // 4
- {"scheme", 1, 0, 0}, // 5
- {"signature-filter", 1, 0, 0}, // 6
- {"intent", 1, 0, 0}, // 7
- {"full-metadata", 0, 0, 0}, // 8
- {"tmpdir", 1, 0, 0}, // 9
- {"upload-script", 1, 0, 0}, // 10
- {"rebuild-statcache", 0, 0, 0}, // 11
- {"exclude-name", 1, 0, 0}, // 12
- // Aliases for short options
- {"verbose", 0, 0, 'v'},
- {NULL, 0, 0, 0},
- };
-
- int long_index;
- int c = getopt_long(argc, argv, "v", long_options, &long_index);
-
- if (c == -1)
- break;
-
- if (c == 0) {
- switch (long_index) {
- case 0: // --localdb
- localdb_dir = optarg;
- break;
- case 1: // --exclude
- if (optarg[0] != '/')
- excludes.push_back(optarg);
- else
- excludes.push_back(optarg + 1);
- break;
- case 2: // --filter
- filter_program = optarg;
- break;
- case 3: // --filter-extension
- filter_extension = optarg;
- break;
- case 4: // --dest
- backup_dest = optarg;
- break;
- case 5: // --scheme
- backup_scheme = optarg;
- break;
- case 6: // --signature-filter
- signature_filter = optarg;
- break;
- case 7: // --intent
- snapshot_intent = atof(optarg);
- if (snapshot_intent <= 0)
- snapshot_intent = 1;
- break;
- case 8: // --full-metadata
- flag_full_metadata = true;
- break;
- case 9: // --tmpdir
- tmp_dir = optarg;
- break;
- case 10: // --upload-script
- backup_script = optarg;
- break;
- case 11: // --rebuild-statcache
- flag_rebuild_statcache = true;
- break;
- case 12: // --exclude-name
- excluded_names.push_back(optarg);
- break;
- default:
- fprintf(stderr, "Unhandled long option!\n");
- return 1;
- }
- } else {
- switch (c) {
- case 'v':
- verbose = true;
- break;
- default:
- usage(argv[0]);
- return 1;
- }
- }
- }
-
- if (optind == argc) {
- usage(argv[0]);
- return 1;
- }
-
- searches.push_back(".");
- for (int i = optind; i < argc; i++)
- add_include(argv[i]);
-
- if (backup_dest == "" && backup_script == "") {
- fprintf(stderr,
- "Error: Backup destination must be specified using --dest= or --upload-script=\n");
- usage(argv[0]);
- return 1;
- }
-
- if (backup_dest != "" && backup_script != "") {
- fprintf(stderr,
- "Error: Cannot specify both --dest= and --upload-script=\n");
- usage(argv[0]);
- return 1;
- }
-
- // Default for --localdb is the same as --dest
- if (localdb_dir == "") {
- localdb_dir = backup_dest;
- }
- if (localdb_dir == "") {
- fprintf(stderr,
- "Error: Must specify local database path with --localdb=\n");
- usage(argv[0]);
- return 1;
- }
-
- block_buf = new char[LBS_BLOCK_SIZE];
-
- /* Initialize the remote storage layer. If using an upload script, create
- * a temporary directory for staging files. Otherwise, write backups
- * directly to the destination directory. */
- if (backup_script != "") {
- tmp_dir = tmp_dir + "/lbs." + generate_uuid();
- if (mkdir(tmp_dir.c_str(), 0700) < 0) {
- fprintf(stderr, "Cannot create temporary directory %s: %m\n",
- tmp_dir.c_str());
- return 1;
- }
- remote = new RemoteStore(tmp_dir, backup_script=backup_script);
- } else {
- remote = new RemoteStore(backup_dest);
- }
-
- /* Store the time when the backup started, so it can be included in the
- * snapshot name. */
- time_t now;
- struct tm time_buf;
- char desc_buf[256];
- time(&now);
- localtime_r(&now, &time_buf);
- strftime(desc_buf, sizeof(desc_buf), "%Y%m%dT%H%M%S", &time_buf);
-
- /* Open the local database which tracks all objects that are stored
- * remotely, for efficient incrementals. Provide it with the name of this
- * snapshot. */
- string database_path = localdb_dir + "/localdb.sqlite";
- db = new LocalDb;
- db->Open(database_path.c_str(), desc_buf, backup_scheme.c_str(),
- snapshot_intent);
-
- tss = new TarSegmentStore(remote, db);
-
- /* Initialize the stat cache, for skipping over unchanged files. */
- metawriter = new MetadataWriter(tss, localdb_dir.c_str(), desc_buf,
- backup_scheme.c_str());
-
- scanfile(".", false);
-
- ObjectReference root_ref = metawriter->close();
- add_segment(root_ref.get_segment());
- string backup_root = root_ref.to_string();
-
- delete metawriter;
-
- tss->sync();
- tss->dump_stats();
- delete tss;
-
- /* Write out a checksums file which lists the checksums for all the
- * segments included in this snapshot. The format is designed so that it
- * may be easily verified using the sha1sums command. */
- const char csum_type[] = "sha1";
- string checksum_filename = "snapshot-";
- if (backup_scheme.size() > 0)
- checksum_filename += backup_scheme + "-";
- checksum_filename = checksum_filename + desc_buf + "." + csum_type + "sums";
- RemoteFile *checksum_file = remote->alloc_file(checksum_filename,
- "checksums");
- FILE *checksums = fdopen(checksum_file->get_fd(), "w");
-
- for (std::set<string>::iterator i = segment_list.begin();
- i != segment_list.end(); ++i) {
- string seg_path, seg_csum;
- if (db->GetSegmentChecksum(*i, &seg_path, &seg_csum)) {
- const char *raw_checksum = NULL;
- if (strncmp(seg_csum.c_str(), csum_type,
- strlen(csum_type)) == 0) {
- raw_checksum = seg_csum.c_str() + strlen(csum_type);
- if (*raw_checksum == '=')
- raw_checksum++;
- else
- raw_checksum = NULL;
- }
-
- if (raw_checksum != NULL)
- fprintf(checksums, "%s *%s\n",
- raw_checksum, seg_path.c_str());
- }
- }
- fclose(checksums);
-
- SHA1Checksum checksum_csum;
- string csum;
- checksum_filename = checksum_file->get_local_path();
- if (checksum_csum.process_file(checksum_filename.c_str())) {
- csum = checksum_csum.checksum_str();
- }
-
- checksum_file->send();
-
- db->Close();
-
- /* All other files should be flushed to remote storage before writing the
- * backup descriptor below, so that it is not possible to have a backup
- * descriptor written out depending on non-existent (not yet written)
- * files. */
- remote->sync();
-
- /* Write a backup descriptor file, which says which segments are needed and
- * where to start to restore this snapshot. The filename is based on the
- * current time. If a signature filter program was specified, filter the
- * data through that to give a chance to sign the descriptor contents. */
- string desc_filename = "snapshot-";
- if (backup_scheme.size() > 0)
- desc_filename += backup_scheme + "-";
- desc_filename = desc_filename + desc_buf + ".lbs";
-
- RemoteFile *descriptor_file = remote->alloc_file(desc_filename,
- "snapshots");
- int descriptor_fd = descriptor_file->get_fd();
- if (descriptor_fd < 0) {
- fprintf(stderr, "Unable to open descriptor output file: %m\n");
- return 1;
- }
- pid_t signature_pid = 0;
- if (signature_filter.size() > 0) {
- int new_fd = spawn_filter(descriptor_fd, signature_filter.c_str(),
- &signature_pid);
- close(descriptor_fd);
- descriptor_fd = new_fd;
- }
- FILE *descriptor = fdopen(descriptor_fd, "w");
-
- fprintf(descriptor, "Format: LBS Snapshot v0.8\n");
- fprintf(descriptor, "Producer: Cumulus %s\n", cumulus_version);
- strftime(desc_buf, sizeof(desc_buf), "%Y-%m-%d %H:%M:%S %z", &time_buf);
- fprintf(descriptor, "Date: %s\n", desc_buf);
- if (backup_scheme.size() > 0)
- fprintf(descriptor, "Scheme: %s\n", backup_scheme.c_str());
- fprintf(descriptor, "Backup-Intent: %g\n", snapshot_intent);
- fprintf(descriptor, "Root: %s\n", backup_root.c_str());
-
- if (csum.size() > 0) {
- fprintf(descriptor, "Checksums: %s\n", csum.c_str());
- }
-
- fprintf(descriptor, "Segments:\n");
- for (std::set<string>::iterator i = segment_list.begin();
- i != segment_list.end(); ++i) {
- fprintf(descriptor, " %s\n", i->c_str());
- }
-
- fclose(descriptor);
-
- if (signature_pid) {
- int status;
- waitpid(signature_pid, &status, 0);
-
- if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
- fatal("Signature filter process error");
- }
- }
-
- descriptor_file->send();
-
- remote->sync();
- delete remote;
-
- if (backup_script != "") {
- if (rmdir(tmp_dir.c_str()) < 0) {
- fprintf(stderr,
- "Warning: Cannot delete temporary directory %s: %m\n",
- tmp_dir.c_str());
- }
- }
-
- return 0;
-}
projects / cumulus.git / blobdiff