-/* LBS: An LFS-inspired filesystem backup system
- * Copyright (C) 2007 Michael Vrable
+/* Cumulus: Efficient Filesystem Backup to the Cloud
+ * Copyright (C) 2008-2009 The Cumulus Developers
+ * See the AUTHORS file for a list of contributors.
*
- * Backup data is stored in a collection of objects, which are grouped together
+ * 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.
+ */
+
+/* Backup data is stored in a collection of objects, which are grouped together
* into segments for storage purposes. This implementation of the object store
* represents segments as TAR files and objects as files within them. */
#include <assert.h>
#include <errno.h>
#include <stdio.h>
+#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/resource.h>
#include <string>
#include <iostream>
+#include "hash.h"
+#include "localdb.h"
#include "store.h"
#include "ref.h"
+#include "util.h"
using std::max;
using std::list;
using std::map;
+using std::pair;
using std::set;
using std::string;
const char *filter_program = "bzip2 -c";
const char *filter_extension = ".bz2";
-static void cloexec(int fd)
-{
- long flags = fcntl(fd, F_GETFD);
-
- if (flags < 0)
- return;
-
- fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
-}
-
-Tarfile::Tarfile(const string &path, const string &segment)
+Tarfile::Tarfile(RemoteFile *file, const string &segment)
: size(0),
segment_name(segment)
{
assert(sizeof(struct tar_header) == TAR_BLOCK_SIZE);
- real_fd = open(path.c_str(), O_WRONLY | O_CREAT, 0666);
- if (real_fd < 0)
- throw IOException("Error opening output file");
-
- filter_fd = spawn_filter(real_fd, filter_program, &filter_pid);
+ this->file = file;
+ this->filter.reset(FileFilter::New(file->get_fd(), filter_program));
}
Tarfile::~Tarfile()
tar_write(buf, TAR_BLOCK_SIZE);
tar_write(buf, TAR_BLOCK_SIZE);
- if (close(filter_fd) != 0)
- throw IOException("Error closing Tarfile");
+ if (close(filter->get_wrapped_fd()) != 0)
+ fatal("Error closing Tarfile");
/* ...and wait for filter process to finish. */
+ if (filter->wait() != 0) {
+ fatal("Filter process error");
+ }
+}
+
+FileFilter::FileFilter(int raw, int wrapped, pid_t pid)
+ : fd_raw(raw), fd_wrapped(wrapped), pid(pid) { }
+
+FileFilter *FileFilter::New(int fd, const char *program)
+{
+ if (program == NULL || strlen(program) == 0) {
+ return new FileFilter(fd, fd, -1);
+ }
+
+ pid_t pid;
+ int wrapped_fd = spawn_filter(fd, program, &pid);
+ return new FileFilter(fd, wrapped_fd, pid);
+}
+
+int FileFilter::wait()
+{
+ // No filter program was launched implies no need to wait.
+ if (pid == -1)
+ return 0;
+
+ // The raw file descriptor was held open to track the output file size, but
+ // is not needed any longer.
+ close(fd_raw);
+
int status;
- waitpid(filter_pid, &status, 0);
+ if (waitpid(pid, &status, 0) < 0) {
+ fprintf(stderr, "Error waiting for filter process: %m\n");
+ return -1;
+ }
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
- throw IOException("Filter process error");
+ fprintf(stderr, "Filter process error: %d\n", WEXITSTATUS(status));
}
- close(real_fd);
+ return status;
}
/* Launch a child process which can act as a filter (compress, encrypt, etc.)
* on the TAR output. The file descriptor to which output should be written
* must be specified; the return value is the file descriptor which will be
* attached to the standard input of the filter program. */
-int spawn_filter(int fd_out, const char *program, pid_t *filter_pid)
+int FileFilter::spawn_filter(int fd_out, const char *program, pid_t *filter_pid)
{
int fds[2];
pid_t pid;
/* Create a pipe for communicating with the filter process. */
if (pipe(fds) < 0) {
- throw IOException("Unable to create pipe for filter");
+ fatal("Unable to create pipe for filter");
}
/* Create a child process which can exec() the filter program. */
pid = fork();
- if (filter_pid < 0)
- throw IOException("Unable to fork filter process");
+ if (pid < 0)
+ fatal("Unable to fork filter process");
- if (filter_pid > 0) {
+ if (pid > 0) {
/* Parent process */
close(fds[0]);
cloexec(fds[1]);
size += len;
while (len > 0) {
- int res = write(filter_fd, data, len);
+ int res = write(filter->get_wrapped_fd(), data, len);
if (res < 0) {
if (errno == EINTR)
continue;
fprintf(stderr, "Write error: %m\n");
- throw IOException("Write error");
+ fatal("Write error");
}
len -= res;
sprintf(header.mode, "%07o", 0600);
sprintf(header.uid, "%07o", 0);
sprintf(header.gid, "%07o", 0);
- sprintf(header.size, "%011o", len);
+ sprintf(header.size, "%011o", (int)len);
sprintf(header.mtime, "%011o", (int)time(NULL));
header.typeflag = '0';
strcpy(header.magic, "ustar ");
{
struct stat statbuf;
- if (fstat(real_fd, &statbuf) == 0)
+ if (fstat(filter->get_raw_fd(), &statbuf) == 0)
return max((int64_t)statbuf.st_size, (int64_t)(size / 128));
/* Couldn't stat the file on disk, so just return the actual number of
static const size_t SEGMENT_SIZE = 4 * 1024 * 1024;
-static map<string, int64_t> group_sizes;
+/* Backup size summary: segment type -> (uncompressed size, compressed size) */
+static map<string, pair<int64_t, int64_t> > group_sizes;
ObjectReference TarSegmentStore::write_object(const char *data, size_t len,
- const std::string &group)
+ const std::string &group,
+ const std::string &checksum,
+ double age)
{
struct segment_info *segment;
segment = new segment_info;
segment->name = generate_uuid();
+ segment->group = group;
segment->basename = segment->name + ".tar";
segment->basename += filter_extension;
- segment->fullname = path + "/" + segment->basename;
- segment->file = new Tarfile(segment->fullname, segment->name);
segment->count = 0;
+ segment->data_size = 0;
+ segment->rf = remote->alloc_file(segment->basename,
+ group == "metadata" ? "segments0"
+ : "segments1");
+ segment->file = new Tarfile(segment->rf, segment->name);
segments[group] = segment;
} else {
segment->file->write_object(id, data, len);
segment->count++;
+ segment->data_size += len;
- group_sizes[group] += len;
+ group_sizes[group].first += len;
ObjectReference ref(segment->name, id_buf);
+ ref.set_range(0, len, true);
+ if (checksum.size() > 0)
+ ref.set_checksum(checksum);
+ if (db != NULL)
+ db->StoreObject(ref, age);
// If this segment meets or exceeds the size target, close it so that
// future objects will go into a new segment.
void TarSegmentStore::dump_stats()
{
printf("Data written:\n");
- for (map<string, int64_t>::iterator i = group_sizes.begin();
+ for (map<string, pair<int64_t, int64_t> >::iterator i = group_sizes.begin();
i != group_sizes.end(); ++i) {
- printf(" %s: %lld\n", i->first.c_str(), i->second);
+ printf(" %s: %lld (%lld compressed)\n", i->first.c_str(),
+ (long long)i->second.first, (long long)i->second.second);
}
}
delete segment->file;
if (db != NULL) {
- SHA1Checksum segment_checksum;
- if (segment_checksum.process_file(segment->fullname.c_str())) {
- string checksum = segment_checksum.checksum_str();
- db->SetSegmentChecksum(segment->name, segment->basename, checksum);
+ struct stat stat_buf;
+ int disk_size = 0;
+ if (stat(segment->rf->get_local_path().c_str(), &stat_buf) == 0) {
+ disk_size = stat_buf.st_size;
+ group_sizes[segment->group].second += disk_size;
}
+
+ string checksum
+ = Hash::hash_file(segment->rf->get_local_path().c_str());
+
+ db->SetSegmentMetadata(segment->name, segment->rf->get_remote_path(),
+ checksum, group, segment->data_size, disk_size);
}
+ segment->rf->send();
+
segments.erase(segments.find(group));
delete segment;
}
}
LbsObject::LbsObject()
- : group(""), data(NULL), data_len(0), written(false)
+ : group(""), age(0.0), data(NULL), data_len(0), written(false)
{
}
{
}
-void LbsObject::write(TarSegmentStore *store)
+void LbsObject::set_data(const char *d, size_t len, const char *checksum)
{
- assert(data != NULL);
- assert(!written);
+ data = d;
+ data_len = len;
- ref = store->write_object(data, data_len, group);
- written = true;
+ if (checksum != NULL) {
+ this->checksum = checksum;
+ } else {
+ Hash *hash = Hash::New();
+ hash->update(data, data_len);
+ this->checksum = hash->digest_str();
+ delete hash;
+ }
}
-void LbsObject::checksum()
+void LbsObject::write(TarSegmentStore *store)
{
- assert(written);
+ assert(data != NULL);
+ assert(!written);
- SHA1Checksum hash;
- hash.process(data, data_len);
- ref.set_checksum(hash.checksum_str());
+ ref = store->write_object(data, data_len, group, checksum, age);
+ written = true;
}