-/* Recursively descend the filesystem and visit each file. */
+/* 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 <stdint.h>
#include <stdio.h>
#include <stdlib.h>
+#include <string.h>
#include <sys/stat.h>
#include <sys/sysmacros.h>
#include <sys/types.h>
#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::ostream;
/* Version information. This will be filled in by the Makefile. */
-#ifndef LBS_VERSION
-#define LBS_VERSION Unknown
+#ifndef CUMULUS_VERSION
+#define CUMULUS_VERSION Unknown
#endif
-#define LBS_STRINGIFY(s) LBS_STRINGIFY2(s)
-#define LBS_STRINGIFY2(s) #s
-static const char lbs_version[] = LBS_STRINGIFY(LBS_VERSION);
+#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;
/* 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)
/* 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. */
+ * 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;
- if (metawriter->find(path) && metawriter->is_unchanged(&stat_buf)) {
+ bool found = metawriter->find(path);
+ if (found)
+ old_blocks = metawriter->get_blocks();
+
+ if (found
+ && !flag_rebuild_statcache
+ && metawriter->is_unchanged(&stat_buf)) {
cached = true;
- list<ObjectReference> blocks = metawriter->get_blocks();
/* 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 = blocks.begin();
- i != blocks.end(); ++i) {
+ for (list<ObjectReference>::const_iterator i = old_blocks.begin();
+ i != old_blocks.end(); ++i) {
const ObjectReference &ref = *i;
if (!db->IsAvailable(ref)) {
cached = false;
/* If everything looks okay, use the cached information */
if (cached) {
file_info["checksum"] = metawriter->get_checksum();
- for (list<ObjectReference>::const_iterator i = blocks.begin();
- i != blocks.end(); ++i) {
+ 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())
- segment_list.insert(ref.get_segment());
+ add_segment(ref.get_segment());
db->UseObject(ref);
}
size = stat_buf.st_size;
* 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)
ref = ObjectReference(ObjectReference::REF_ZERO);
ref.set_range(0, bytes);
} else {
- ObjectReference ref = db->FindObject(block_csum, bytes);
+ 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;
status = "new";
}
- o->set_data(block_buf, bytes);
- o->write(tss);
- ref = o->get_ref();
- db->StoreObject(ref, block_csum, bytes, block_age);
- delete o;
+ 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);
}
- object_list.push_back(ref.to_string());
- if (ref.is_normal())
- segment_list.insert(ref.get_segment());
- db->UseObject(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)
file_info["checksum"] = hash.checksum_str();
}
- if (status != NULL)
+ // 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 = "";
int64_t file_size;
ssize_t len;
- printf("%s\n", path.c_str());
+ if (verbose)
+ printf("%s\n", path.c_str());
metawriter->find(path);
file_info["name"] = uri_encode(path);
file_info["volatile"] = "1";
struct passwd *pwd = getpwuid(stat_buf.st_uid);
- if (pwd != NULL) {
+ if (pwd != NULL && pwd->pw_name != NULL) {
file_info["user"] += " (" + uri_encode(pwd->pw_name) + ")";
}
struct group *grp = getgrgid(stat_buf.st_gid);
- if (pwd != NULL) {
+ if (grp != NULL && grp->gr_name != NULL) {
file_info["group"] += " (" + uri_encode(grp->gr_name) + ")";
}
for (list<string>::iterator i = includes.begin();
i != includes.end(); ++i) {
if (path == *i) {
- printf("Including %s\n", path.c_str());
include = true;
}
}
for (list<string>::iterator i = excludes.begin();
i != excludes.end(); ++i) {
if (path == *i) {
- printf("Excluding %s\n", path.c_str());
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) {
- printf("Scanning %s\n", path.c_str());
scan_only = true;
}
}
* themselves are excluded from being backed up. */
void add_include(const char *path)
{
- printf("Add: %s\n", 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. */
{
fprintf(
stderr,
- "LBS %s\n\n"
+ "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 [REQUIRED]\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"
" (defaults to \".bz2\")\n"
" --signature-filter=COMMAND\n"
" program though which to filter descriptor\n"
- " --scheme=NAME optional name for this snapshot\n",
- lbs_version, program
+ " --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 = "";
+ 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
{"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, "", long_options, &long_index);
+ int c = getopt_long(argc, argv, "v", long_options, &long_index);
if (c == -1)
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 {
- usage(argv[0]);
- return 1;
+ switch (c) {
+ case 'v':
+ verbose = true;
+ break;
+ default:
+ usage(argv[0]);
+ return 1;
+ }
}
}
for (int i = optind; i < argc; i++)
add_include(argv[i]);
- if (backup_dest == "") {
+ if (backup_dest == "" && backup_script == "") {
fprintf(stderr,
- "Error: Backup destination must be specified with --dest=\n");
+ "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;
}
if (localdb_dir == "") {
localdb_dir = backup_dest;
}
-
- // Dump paths for debugging/informational purposes
- {
- list<string>::const_iterator i;
-
- printf("LBS Version: %s\n", lbs_version);
-
- printf("--dest=%s\n--localdb=%s\n\n",
- backup_dest.c_str(), localdb_dir.c_str());
-
- printf("Includes:\n");
- for (i = includes.begin(); i != includes.end(); ++i)
- printf(" %s\n", i->c_str());
-
- printf("Excludes:\n");
- for (i = excludes.begin(); i != excludes.end(); ++i)
- printf(" %s\n", i->c_str());
-
- printf("Searching:\n");
- for (i = searches.begin(); i != searches.end(); ++i)
- printf(" %s\n", i->c_str());
+ 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;
* snapshot. */
string database_path = localdb_dir + "/localdb.sqlite";
db = new LocalDb;
- db->Open(database_path.c_str(), desc_buf,
- backup_scheme.size() ? backup_scheme.c_str() : NULL);
+ db->Open(database_path.c_str(), desc_buf, backup_scheme.c_str(),
+ snapshot_intent);
- tss = new TarSegmentStore(backup_dest, db);
+ 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.size()
- ? backup_scheme.c_str()
- : NULL);
+ backup_scheme.c_str());
scanfile(".", false);
* 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 = backup_dest + "/snapshot-";
+ string checksum_filename = "snapshot-";
if (backup_scheme.size() > 0)
checksum_filename += backup_scheme + "-";
checksum_filename = checksum_filename + desc_buf + "." + csum_type + "sums";
- FILE *checksums = fopen(checksum_filename.c_str(), "w");
- if (checksums != NULL) {
- 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;
- }
+ RemoteFile *checksum_file = remote->alloc_file(checksum_filename,
+ "checksums");
+ FILE *checksums = fdopen(checksum_file->get_fd(), "w");
- if (raw_checksum != NULL)
- fprintf(checksums, "%s *%s\n",
- raw_checksum, seg_path.c_str());
+ 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);
- } else {
- fprintf(stderr, "ERROR: Unable to write checksums file: %m\n");
}
+ 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 = backup_dest + "/snapshot-";
+ string desc_filename = "snapshot-";
if (backup_scheme.size() > 0)
desc_filename += backup_scheme + "-";
desc_filename = desc_filename + desc_buf + ".lbs";
- int descriptor_fd = open(desc_filename.c_str(), O_WRONLY | O_CREAT, 0666);
+ 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;
}
FILE *descriptor = fdopen(descriptor_fd, "w");
- fprintf(descriptor, "Format: LBS Snapshot v0.6\n");
- fprintf(descriptor, "Producer: LBS %s\n", lbs_version);
+ 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());
- SHA1Checksum checksum_csum;
- if (checksum_csum.process_file(checksum_filename.c_str())) {
- string csum = checksum_csum.checksum_str();
+ if (csum.size() > 0) {
fprintf(descriptor, "Checksums: %s\n", csum.c_str());
}
waitpid(signature_pid, &status, 0);
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
- throw IOException("Signature filter process error");
+ 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());
}
}
projects / cumulus.git / blobdiff