X-Git-Url: http://git.vrable.net/?p=cumulus.git;a=blobdiff_plain;f=scandir.cc;h=8af3175b64c3b6007a5497f4c4ac8d81e5d9ff7c;hp=f653f4335d9ab69e7fff9c66a49669844fd39670;hb=f38dd9bcb0caffd3fc9126b05788c936690e8288;hpb=cc2d3611ed50f5965a9138ffaf3262417993c4f8 diff --git a/scandir.cc b/scandir.cc index f653f43..8af3175 100644 --- a/scandir.cc +++ b/scandir.cc @@ -1,4 +1,25 @@ -/* 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 + * + * 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 #include @@ -9,6 +30,7 @@ #include #include #include +#include #include #include #include @@ -26,8 +48,10 @@ #include "localdb.h" #include "metadata.h" +#include "remote.h" #include "store.h" #include "sha1.h" +#include "subfile.h" #include "util.h" using std::list; @@ -36,13 +60,14 @@ using std::vector; 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; @@ -65,12 +90,18 @@ double snapshot_intent = 1.0; /* Selection of files to include/exclude in the snapshot. */ std::list includes; // Paths in which files should be saved std::list excludes; // Paths which will not be saved +std::list excluded_names; // Directories which will not be saved std::list 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) @@ -116,17 +147,25 @@ int64_t dumpfile(int fd, dictionary &file_info, const string &path, /* 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 old_blocks; + + bool found = metawriter->find(path); + if (found) + old_blocks = metawriter->get_blocks(); - if (metawriter->find(path) && metawriter->is_unchanged(&stat_buf)) { + if (found + && !flag_rebuild_statcache + && metawriter->is_unchanged(&stat_buf)) { cached = true; - list 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::const_iterator i = blocks.begin(); - i != blocks.end(); ++i) { + for (list::const_iterator i = old_blocks.begin(); + i != old_blocks.end(); ++i) { const ObjectReference &ref = *i; if (!db->IsAvailable(ref)) { cached = false; @@ -138,8 +177,8 @@ int64_t dumpfile(int fd, dictionary &file_info, const string &path, /* If everything looks okay, use the cached information */ if (cached) { file_info["checksum"] = metawriter->get_checksum(); - for (list::const_iterator i = blocks.begin(); - i != blocks.end(); ++i) { + for (list::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()) @@ -154,6 +193,9 @@ int64_t dumpfile(int fd, dictionary &file_info, const string &path, * 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) @@ -189,9 +231,11 @@ int64_t dumpfile(int fd, dictionary &file_info, const string &path, 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 refs; + // Store a copy of the object if one does not yet exist if (ref.is_null()) { LbsObject *o = new LbsObject; @@ -224,17 +268,23 @@ int64_t dumpfile(int fd, dictionary &file_info, const string &path, 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()) - add_segment(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) @@ -244,7 +294,25 @@ int64_t dumpfile(int fd, dictionary &file_info, const string &path, 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 = ""; @@ -272,7 +340,8 @@ void dump_inode(const string& path, // Path within snapshot 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); @@ -288,12 +357,12 @@ void dump_inode(const string& path, // Path within snapshot 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) + ")"; } @@ -391,7 +460,6 @@ void scanfile(const string& path, bool include) for (list::iterator i = includes.begin(); i != includes.end(); ++i) { if (path == *i) { - printf("Including %s\n", path.c_str()); include = true; } } @@ -399,15 +467,28 @@ void scanfile(const string& path, bool include) for (list::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::iterator i = excluded_names.begin(); + i != excluded_names.end(); ++i) { + if (name == *i) { + include = false; + } + } + } + for (list::iterator i = searches.begin(); i != searches.end(); ++i) { if (path == *i) { - printf("Scanning %s\n", path.c_str()); scan_only = true; } } @@ -508,7 +589,6 @@ void scanfile(const string& path, bool include) * 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. */ @@ -547,14 +627,19 @@ void usage(const char *program) { 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" @@ -564,18 +649,27 @@ void usage(const char *program) " 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", - lbs_version, program + " (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 @@ -586,11 +680,18 @@ int main(int argc, char *argv[]) {"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; @@ -626,13 +727,34 @@ int main(int argc, char *argv[]) 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; + } } } @@ -645,9 +767,16 @@ int main(int argc, char *argv[]) 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 using --dest= or --upload-script=\n"); + usage(argv[0]); + return 1; + } + + if (backup_dest != "" && backup_script != "") { fprintf(stderr, - "Error: Backup destination must be specified with --dest=\n"); + "Error: Cannot specify both --dest= and --upload-script=\n"); usage(argv[0]); return 1; } @@ -656,31 +785,30 @@ int main(int argc, char *argv[]) if (localdb_dir == "") { localdb_dir = backup_dest; } - - // Dump paths for debugging/informational purposes - { - list::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; @@ -695,17 +823,14 @@ int main(int argc, char *argv[]) * 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); @@ -723,48 +848,64 @@ int main(int argc, char *argv[]) * 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::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::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; @@ -778,17 +919,16 @@ int main(int argc, char *argv[]) } 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()); } @@ -805,7 +945,20 @@ int main(int argc, char *argv[]) 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()); } }