#include <algorithm>
#include <string>
+#include <list>
#include <vector>
#include <iostream>
+#include <fstream>
#include <sstream>
+#include <set>
#include "format.h"
#include "store.h"
-#include "tarstore.h"
#include "sha1.h"
+using std::list;
using std::string;
using std::vector;
using std::ostream;
-static SegmentStore *segment_store;
-static OutputStream *info_dump = NULL;
-
static TarSegmentStore *tss = NULL;
-static SegmentPartitioner *index_segment, *data_segment;
-
/* Buffer for holding a single block of data read from a file. */
-static const int LBS_BLOCK_SIZE = 1024 * 1024;
+static const size_t LBS_BLOCK_SIZE = 1024 * 1024;
static char *block_buf;
-void scandir(const string& path, std::ostream& metadata);
+static const size_t LBS_METADATA_BLOCK_SIZE = 65536;
+
+/* Contents of the root object. This will contain a set of indirect links to
+ * the metadata objects. */
+std::ostringstream metadata_root;
+
+/* Buffer for building up metadata. */
+std::ostringstream metadata;
-/* Converts time to microseconds since the epoch. */
-int64_t encode_time(time_t time)
+/* Keep track of all segments which are needed to reconstruct the snapshot. */
+std::set<string> segment_list;
+
+void scandir(const string& path);
+
+/* Ensure contents of metadata are flushed to an object. */
+void metadata_flush()
{
- return (int64_t)time * 1000000;
+ string m = metadata.str();
+ if (m.size() == 0)
+ return;
+
+ /* Write current metadata information to a new object. */
+ LbsObject *meta = new LbsObject;
+ meta->set_group("root");
+ meta->set_data(m.data(), m.size());
+ meta->write(tss);
+ meta->checksum();
+
+ /* Write a reference to this block in the root. */
+ ObjectReference ref = meta->get_ref();
+ metadata_root << "@" << ref.to_string() << "\n";
+ segment_list.insert(ref.get_segment());
+
+ delete meta;
+
+ metadata.str("");
}
/* Read data from a file descriptor and return the amount of data read. A
/* Read the contents of a file (specified by an open file descriptor) and copy
* the data to the store. */
-void dumpfile(int fd, dictionary &file_info, ostream &metadata)
+void dumpfile(int fd, dictionary &file_info)
{
struct stat stat_buf;
fstat(fd, &stat_buf);
int64_t size = 0;
- string segment_list = "data:";
+ list<string> object_list;
if ((stat_buf.st_mode & S_IFMT) != S_IFREG) {
- printf("file is no longer a regular file!\n");
+ fprintf(stderr, "file is no longer a regular file!\n");
return;
}
* that actually comprise the file data. This level of indirection is used
* so that the same data block can be used in multiple files, or multiple
* versions of the same file. */
- struct uuid segment_uuid;
- int object_id;
- OutputStream *index_data = index_segment->new_object(&segment_uuid,
- &object_id,
- "DREF");
-
SHA1Checksum hash;
while (true) {
- struct uuid block_segment_uuid;
- int block_object_id;
-
size_t bytes = file_read(fd, block_buf, LBS_BLOCK_SIZE);
if (bytes == 0)
break;
hash.process(block_buf, bytes);
- OutputStream *block = data_segment->new_object(&block_segment_uuid,
- &block_object_id,
- "DATA");
- block->write(block_buf, bytes);
- index_data->write_uuid(block_segment_uuid);
- index_data->write_u32(block_object_id);
// tarstore processing
- string blockid = tss->write_object(block_buf, bytes, "data");
- segment_list += " " + blockid;
+ LbsObject *o = new LbsObject;
+ o->set_group("data");
+ o->set_data(block_buf, bytes);
+ o->write(tss);
+ object_list.push_back(o->get_name());
+ segment_list.insert(o->get_ref().get_segment());
+ delete o;
size += bytes;
}
- file_info["sha1"] = string((const char *)hash.checksum(),
- hash.checksum_size());
- file_info["data"] = encode_objref(segment_uuid, object_id);
+ file_info["checksum"] = hash.checksum_str();
+
+ /* For files that only need to be broken apart into a few objects, store
+ * the list of objects directly. For larger files, store the data
+ * out-of-line and provide a pointer to the indrect object. */
+ if (object_list.size() < 8) {
+ string blocklist = "";
+ for (list<string>::iterator i = object_list.begin();
+ i != object_list.end(); ++i) {
+ if (i != object_list.begin())
+ blocklist += " ";
+ blocklist += *i;
+ }
+ file_info["data"] = blocklist;
+ } else {
+ string blocklist = "";
+ for (list<string>::iterator i = object_list.begin();
+ i != object_list.end(); ++i) {
+ blocklist += *i + "\n";
+ }
- metadata << segment_list << "\n";
+ LbsObject *i = new LbsObject;
+ i->set_group("indirect");
+ i->set_data(blocklist.data(), blocklist.size());
+ i->write(tss);
+ file_info["data"] = "@" + i->get_name();
+ segment_list.insert(i->get_ref().get_segment());
+ delete i;
+ }
}
-void scanfile(const string& path, ostream &metadata)
+void scanfile(const string& path)
{
int fd;
long flags;
struct stat stat_buf;
char *buf;
ssize_t len;
+ list<string> refs;
// Set to true if the item is a directory and we should recursively scan
bool recurse = false;
printf("%s\n", path.c_str());
metadata << "name: " << uri_encode(path) << "\n";
- metadata << "mode: " << (stat_buf.st_mode & 07777) << "\n";
- metadata << "atime: " << stat_buf.st_atime << "\n";
- metadata << "ctime: " << stat_buf.st_ctime << "\n";
- metadata << "mtime: " << stat_buf.st_mtime << "\n";
- metadata << "user: " << stat_buf.st_uid << "\n";
- metadata << "group: " << stat_buf.st_gid << "\n";
-
- file_info["mode"] = encode_u16(stat_buf.st_mode & 07777);
- file_info["atime"] = encode_u64(encode_time(stat_buf.st_atime));
- file_info["ctime"] = encode_u64(encode_time(stat_buf.st_ctime));
- file_info["mtime"] = encode_u64(encode_time(stat_buf.st_mtime));
- file_info["user"] = encode_u32(stat_buf.st_uid);
- file_info["group"] = encode_u32(stat_buf.st_gid);
+
+ file_info["mode"] = encode_int(stat_buf.st_mode & 07777);
+ file_info["atime"] = encode_int(stat_buf.st_atime);
+ 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);
char inode_type;
buf = new char[stat_buf.st_size + 2];
len = readlink(path.c_str(), buf, stat_buf.st_size + 1);
if (len < 0) {
- printf("error reading symlink: %m\n");
+ fprintf(stderr, "error reading symlink: %m\n");
} else if (len <= stat_buf.st_size) {
buf[len] = '\0';
- printf(" contents=%s\n", buf);
+ file_info["contents"] = uri_encode(buf);
} else if (len > stat_buf.st_size) {
- printf("error reading symlink: name truncated\n");
+ fprintf(stderr, "error reading symlink: name truncated\n");
}
- file_info["contents"] = buf;
-
delete[] buf;
break;
case S_IFREG:
flags = fcntl(fd, F_GETFL);
fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
- file_info["size"] = encode_u64(stat_buf.st_size);
- dumpfile(fd, file_info, metadata);
+ file_info["size"] = encode_int(stat_buf.st_size);
+ dumpfile(fd, file_info);
close(fd);
break;
}
file_info["type"] = string(1, inode_type);
- metadata << "type: " << inode_type << "\n";
-
- info_dump->write_string(path);
- info_dump->write_dictionary(file_info);
+ dict_output(metadata, file_info);
metadata << "\n";
+ // Break apart metadata listing if it becomes too large.
+ if (metadata.str().size() > LBS_METADATA_BLOCK_SIZE)
+ metadata_flush();
+
// If we hit a directory, now that we've written the directory itself,
// recursively scan the directory.
if (recurse)
- scandir(path, metadata);
+ scandir(path);
}
-void scandir(const string& path, ostream &metadata)
+void scandir(const string& path)
{
DIR *dir = opendir(path.c_str());
if (dir == NULL) {
- printf("Error: %m\n");
+ fprintf(stderr, "Error: %m\n");
return;
}
for (vector<string>::iterator i = contents.begin();
i != contents.end(); ++i) {
const string& filename = *i;
- scanfile(path + "/" + filename, metadata);
+ scanfile(path + "/" + filename);
}
closedir(dir);
{
block_buf = new char[LBS_BLOCK_SIZE];
- tss = new TarSegmentStore(".");
- segment_store = new SegmentStore(".");
- SegmentWriter *sw = segment_store->new_segment();
- info_dump = sw->new_object(NULL, "ROOT");
+ string backup_dest = ".";
- index_segment = new SegmentPartitioner(segment_store);
- data_segment = new SegmentPartitioner(segment_store);
+ if (argc > 1)
+ backup_dest = argv[1];
- string uuid = SegmentWriter::format_uuid(sw->get_uuid());
- printf("Backup UUID: %s\n", uuid.c_str());
+ tss = new TarSegmentStore(backup_dest);
- std::ostringstream metadata;
+ string desc_filename = backup_dest + "/snapshot.lbs";
+ std::ofstream descriptor(desc_filename.c_str());
try {
- scanfile(".", metadata);
+ scanfile(".");
} catch (IOException e) {
fprintf(stderr, "IOException: %s\n", e.getError().c_str());
}
- const string md = metadata.str();
- string root = tss->write_object(md.data(), md.size(), "root");
+ metadata_flush();
+ const string md = metadata_root.str();
+
+ LbsObject *root = new LbsObject;
+ root->set_group("root");
+ root->set_data(md.data(), md.size());
+ root->write(tss);
+ root->checksum();
+
+ segment_list.insert(root->get_ref().get_segment());
+ descriptor << "root: " << root->get_ref().to_string() << "\n\n";
- fprintf(stderr, "Metadata root is at %s\n", root.c_str());
+ delete root;
+
+ descriptor << "segments:\n";
+ for (std::set<string>::iterator i = segment_list.begin();
+ i != segment_list.end(); ++i) {
+ descriptor << " " << *i << "\n";
+ }
tss->sync();
delete tss;
- delete index_segment;
- delete data_segment;
- delete sw;
-
return 0;
}