-/* LBS: An LFS-inspired filesystem backup system
- * Copyright (C) 2007 Michael Vrable
+/* Cumulus: Smart Filesystem Backup to Dumb Servers
*
- * Backup data is stored in a collection of objects, which are grouped together
+ * Copyright (C) 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.
+ */
+
+/* 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>
using std::max;
using std::list;
using std::map;
+using std::pair;
using std::set;
using std::string;
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);
+ this->file = file;
+ real_fd = file->get_fd();
+ filter_fd = spawn_filter(real_fd, filter_program, &filter_pid);
}
Tarfile::~Tarfile()
* 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 Tarfile::spawn_filter(int fd_out)
+int 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) {
}
/* Create a child process which can exec() the filter program. */
- filter_pid = fork();
- if (filter_pid < 0)
+ pid = fork();
+ if (pid < 0)
throw IOException("Unable to fork filter process");
- if (filter_pid > 0) {
+ if (pid > 0) {
/* Parent process */
close(fds[0]);
cloexec(fds[1]);
+ if (filter_pid != NULL)
+ *filter_pid = pid;
} else {
/* Child process. Rearrange file descriptors. stdin is fds[0], stdout
* is fd_out, stderr is unchanged. */
close(fd_out);
/* Exec the filter program. */
- execlp("/bin/sh", "/bin/sh", "-c", filter_program, NULL);
+ execlp("/bin/sh", "/bin/sh", "-c", program, NULL);
/* Should not reach here except for error cases. */
fprintf(stderr, "Could not exec filter: %m\n");
void Tarfile::write_object(int id, const char *data, size_t len)
{
+ struct tar_header header;
+ memset(&header, 0, sizeof(header));
+
char buf[64];
sprintf(buf, "%08x", id);
string path = segment_name + "/" + buf;
- internal_write_object(path, data, len);
-}
-
-void Tarfile::internal_write_object(const string &path,
- const char *data, size_t len)
-{
- struct tar_header header;
- memset(&header, 0, sizeof(header));
-
assert(path.size() < 100);
memcpy(header.name, path.data(), path.size());
sprintf(header.mode, "%07o", 0600);
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)
segment = new segment_info;
segment->name = generate_uuid();
-
- string filename = path + "/" + segment->name + ".tar";
- filename += filter_extension;
- segment->file = new Tarfile(filename, segment->name);
-
+ segment->group = group;
+ segment->basename = segment->name + ".tar";
+ segment->basename += filter_extension;
segment->count = 0;
+ segment->size = 0;
+ segment->rf = remote->alloc_file(segment->basename, "segments");
+ segment->file = new Tarfile(segment->rf, segment->name);
segments[group] = segment;
} else {
segment->file->write_object(id, data, len);
segment->count++;
+ segment->size += len;
- group_sizes[group] += len;
+ group_sizes[group].first += len;
ObjectReference ref(segment->name, id_buf);
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(),
+ i->second.first, i->second.second);
}
}
struct segment_info *segment = segments[group];
delete segment->file;
+
+ if (db != NULL) {
+ SHA1Checksum segment_checksum;
+ if (segment_checksum.process_file(segment->rf->get_local_path().c_str())) {
+ string checksum = segment_checksum.checksum_str();
+ db->SetSegmentChecksum(segment->name, segment->basename, checksum,
+ segment->size);
+ }
+
+ struct stat stat_buf;
+ if (stat(segment->rf->get_local_path().c_str(), &stat_buf) == 0) {
+ group_sizes[segment->group].second += stat_buf.st_size;
+ }
+ }
+
+ segment->rf->send();
+
segments.erase(segments.find(group));
delete segment;
}