From: Michael Vrable <mvrable@cs.ucsd.edu>
Date: Thu, 3 May 2007 22:13:21 +0000 (-0700)
Subject: Rename tarstore -> store, since it is the only implementation now.
X-Git-Url: http://git.vrable.net/?p=cumulus.git;a=commitdiff_plain;h=d5afe2c08724b4b263a76f187e39861c1e6e0cf5

Rename tarstore -> store, since it is the only implementation now.
---

diff --git a/Makefile b/Makefile
index f8c9ec7..ffa28a3 100644
--- a/Makefile
+++ b/Makefile
@@ -3,7 +3,7 @@ CXXFLAGS=-O -Wall -D_FILE_OFFSET_BITS=64 -g -pg \
 	 `pkg-config --cflags $(PACKAGES)`
 LDFLAGS=-g -pg -ltar `pkg-config --libs $(PACKAGES)`
 
-SRCS=format.cc scandir.cc sha1.cc tarstore.cc
+SRCS=format.cc scandir.cc sha1.cc store.cc
 OBJS=$(SRCS:.cc=.o)
 
 scandir : $(OBJS)
diff --git a/scandir.cc b/scandir.cc
index dc10771..f3bf302 100644
--- a/scandir.cc
+++ b/scandir.cc
@@ -18,7 +18,7 @@
 #include <sstream>
 
 #include "format.h"
-#include "tarstore.h"
+#include "store.h"
 #include "sha1.h"
 
 using std::list;
diff --git a/store.cc b/store.cc
new file mode 100644
index 0000000..00fd26c
--- /dev/null
+++ b/store.cc
@@ -0,0 +1,185 @@
+/* LBS: An LFS-inspired filesystem backup system
+ * Copyright (C) 2007  Michael Vrable
+ *
+ * Backup data is stored in a collection of objects, which are grouped together
+ * into segments for storage purposes.  This implementation of the object store
+ * is built on top of libtar, and represents segments as TAR files and objects
+ * as files within them. */
+
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <time.h>
+#include <uuid/uuid.h>
+
+#include <list>
+#include <set>
+#include <string>
+#include <iostream>
+
+#include "store.h"
+
+using std::list;
+using std::set;
+using std::string;
+
+list<string> TarSegmentStore::norefs;
+
+Tarfile::Tarfile(const string &path, const string &segment)
+    : size(0),
+      segment_name(segment)
+{
+    if (tar_open(&t, (char *)path.c_str(), NULL, O_WRONLY | O_CREAT, 0600,
+                 TAR_VERBOSE | TAR_GNU) == -1)
+        throw IOException("Error opening Tarfile");
+}
+
+Tarfile::~Tarfile()
+{
+    string checksum_list = checksums.str();
+    internal_write_object(segment_name + "/checksums",
+                          checksum_list.data(), checksum_list.size());
+    tar_append_eof(t);
+
+    if (tar_close(t) != 0)
+        throw IOException("Error closing Tarfile");
+}
+
+void Tarfile::write_object(int id, const char *data, size_t len)
+{
+    char buf[64];
+    sprintf(buf, "%08x", id);
+    string path = segment_name + "/" + buf;
+
+    internal_write_object(path, data, len);
+
+    // Compute a checksum for the data block, which will be stored at the end
+    // of the TAR file.
+    SHA1Checksum hash;
+    hash.process(data, len);
+    sprintf(buf, "%08x", id);
+    checksums << buf << " " << hash.checksum_str() << "\n";
+}
+
+void Tarfile::internal_write_object(const string &path,
+                                    const char *data, size_t len)
+{
+    memset(&t->th_buf, 0, sizeof(struct tar_header));
+
+    th_set_type(t, S_IFREG | 0600);
+    th_set_user(t, 0);
+    th_set_group(t, 0);
+    th_set_mode(t, 0600);
+    th_set_size(t, len);
+    th_set_mtime(t, time(NULL));
+    th_set_path(t, const_cast<char *>(path.c_str()));
+    th_finish(t);
+
+    if (th_write(t) != 0)
+        throw IOException("Error writing tar header");
+
+    size += T_BLOCKSIZE;
+
+    if (len == 0)
+        return;
+
+    size_t blocks = (len + T_BLOCKSIZE - 1) / T_BLOCKSIZE;
+    size_t padding = blocks * T_BLOCKSIZE - len;
+
+    for (size_t i = 0; i < blocks - 1; i++) {
+        if (tar_block_write(t, &data[i * T_BLOCKSIZE]) == -1)
+            throw IOException("Error writing tar block");
+    }
+
+    char block[T_BLOCKSIZE];
+    memset(block, 0, sizeof(block));
+    memcpy(block, &data[T_BLOCKSIZE * (blocks - 1)], T_BLOCKSIZE - padding);
+    if (tar_block_write(t, block) == -1)
+        throw IOException("Error writing final tar block");
+
+    size += blocks * T_BLOCKSIZE;
+}
+
+static const size_t SEGMENT_SIZE = 4 * 1024 * 1024;
+
+string TarSegmentStore::write_object(const char *data, size_t len, const
+                                     std::string &group,
+                                     const std::list<std::string> &refs)
+{
+    struct segment_info *segment;
+
+    // Find the segment into which the object should be written, looking up by
+    // group.  If no segment exists yet, create one.
+    if (segments.find(group) == segments.end()) {
+        segment = new segment_info;
+
+        uint8_t uuid[16];
+        char uuid_buf[40];
+        uuid_generate(uuid);
+        uuid_unparse_lower(uuid, uuid_buf);
+        segment->name = uuid_buf;
+
+        string filename = path + "/" + segment->name + ".tar";
+        segment->file = new Tarfile(filename, segment->name);
+
+        segment->count = 0;
+
+        segments[group] = segment;
+    } else {
+        segment = segments[group];
+    }
+
+    int id = segment->count;
+    char id_buf[64];
+    sprintf(id_buf, "%08x", id);
+
+    segment->file->write_object(id, data, len);
+    segment->count++;
+
+    string full_name = segment->name + "/" + id_buf;
+
+    // Store any dependencies this object has on other segments, so they can be
+    // written when the segment is closed.
+    for (list<string>::const_iterator i = refs.begin(); i != refs.end(); ++i) {
+        segment->refs.insert(*i);
+    }
+
+    // If this segment meets or exceeds the size target, close it so that
+    // future objects will go into a new segment.
+    if (segment->file->size_estimate() >= SEGMENT_SIZE)
+        close_segment(group);
+
+    return full_name;
+}
+
+void TarSegmentStore::sync()
+{
+    while (!segments.empty())
+        close_segment(segments.begin()->first);
+}
+
+void TarSegmentStore::close_segment(const string &group)
+{
+    struct segment_info *segment = segments[group];
+    fprintf(stderr, "Closing segment group %s (%s)\n",
+            group.c_str(), segment->name.c_str());
+
+    string reflist;
+    for (set<string>::iterator i = segment->refs.begin();
+         i != segment->refs.end(); ++i) {
+        reflist += *i + "\n";
+    }
+    segment->file->internal_write_object(segment->name + "/references",
+                                         reflist.data(), reflist.size());
+
+    delete segment->file;
+    segments.erase(segments.find(group));
+    delete segment;
+}
+
+string TarSegmentStore::object_reference_to_segment(const string &object)
+{
+    return object;
+}
diff --git a/store.h b/store.h
new file mode 100644
index 0000000..6acee7f
--- /dev/null
+++ b/store.h
@@ -0,0 +1,104 @@
+/* LBS: An LFS-inspired filesystem backup system
+ * Copyright (C) 2006  Michael Vrable
+ *
+ * Backup data is stored in a collection of objects, which are grouped together
+ * into segments for storage purposes.  This implementation of the object store
+ * is built on top of libtar, and represents segments as TAR files and objects
+ * as files within them. */
+
+#ifndef _LBS_TARSTORE_H
+#define _LBS_TARSTORE_H
+
+#include <stdint.h>
+#include <libtar.h>
+
+#include <list>
+#include <map>
+#include <set>
+#include <string>
+#include <iostream>
+#include <sstream>
+
+#include "sha1.h"
+
+/* In memory datatype to represent key/value pairs of information, such as file
+ * metadata.  Currently implemented as map<string, string>. */
+typedef std::map<std::string, std::string> dictionary;
+
+/* IOException will be thrown if an error occurs while reading or writing in
+ * one of the I/O wrappers.  Depending upon the context; this may be fatal or
+ * not--typically, errors reading/writing the store will be serious, but errors
+ * reading an individual file are less so. */
+class IOException : public std::exception {
+private:
+    std::string error;
+public:
+    explicit IOException(const std::string &err) { error = err; }
+    virtual ~IOException() throw () { }
+    std::string getError() const { return error; }
+};
+
+/* A simple wrapper around a single TAR file to represent a segment.  Objects
+ * may only be written out all at once, since the tar header must be written
+ * first; incremental writing is not supported. */
+class Tarfile {
+public:
+    Tarfile(const std::string &path, const std::string &segment);
+    ~Tarfile();
+
+    void write_object(int id, const char *data, size_t len);
+
+    // Return an estimate of the size of the file.
+    size_t size_estimate() { return size; }
+
+    void internal_write_object(const std::string &path,
+                               const char *data, size_t len);
+
+private:
+    size_t size;
+    std::string segment_name;
+    std::ostringstream checksums;
+    TAR *t;
+};
+
+class TarSegmentStore {
+public:
+    // New segments will be stored in the given directory.
+    TarSegmentStore(const std::string &path) { this->path = path; }
+    ~TarSegmentStore() { sync(); }
+
+    // Writes an object to segment in the store, and returns the name
+    // (segment/object) to refer to it.  The optional parameter group can be
+    // used to control object placement; objects with different group
+    // parameters are kept in separate segments.
+    std::string write_object(const char *data, size_t len,
+                             const std::string &group = "",
+                             const std::list<std::string> &refs = norefs);
+
+    // Ensure all segments have been fully written.
+    void sync();
+
+private:
+    struct segment_info {
+        Tarfile *file;
+        std::string name;           // UUID
+        std::set<std::string> refs; // Other segments this one refers to
+        int count;                  // Objects written to this segment
+    };
+
+    std::string path;
+    std::map<std::string, struct segment_info *> segments;
+
+    // An empty list which can be used as an argument to write_object to
+    // indicate that this object depends on no others.
+    static std::list<std::string> norefs;
+
+    // Ensure that all segments in the given group have been fully written.
+    void close_segment(const std::string &group);
+
+    // Parse an object reference string and return just the segment name
+    // portion.
+    std::string object_reference_to_segment(const std::string &object);
+};
+
+#endif // _LBS_TARSTORE_H
diff --git a/tarstore.cc b/tarstore.cc
deleted file mode 100644
index 5133c66..0000000
--- a/tarstore.cc
+++ /dev/null
@@ -1,185 +0,0 @@
-/* LBS: An LFS-inspired filesystem backup system
- * Copyright (C) 2007  Michael Vrable
- *
- * Backup data is stored in a collection of objects, which are grouped together
- * into segments for storage purposes.  This implementation of the object store
- * is built on top of libtar, and represents segments as TAR files and objects
- * as files within them. */
-
-#include <stdio.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <time.h>
-#include <uuid/uuid.h>
-
-#include <list>
-#include <set>
-#include <string>
-#include <iostream>
-
-#include "tarstore.h"
-
-using std::list;
-using std::set;
-using std::string;
-
-list<string> TarSegmentStore::norefs;
-
-Tarfile::Tarfile(const string &path, const string &segment)
-    : size(0),
-      segment_name(segment)
-{
-    if (tar_open(&t, (char *)path.c_str(), NULL, O_WRONLY | O_CREAT, 0600,
-                 TAR_VERBOSE | TAR_GNU) == -1)
-        throw IOException("Error opening Tarfile");
-}
-
-Tarfile::~Tarfile()
-{
-    string checksum_list = checksums.str();
-    internal_write_object(segment_name + "/checksums",
-                          checksum_list.data(), checksum_list.size());
-    tar_append_eof(t);
-
-    if (tar_close(t) != 0)
-        throw IOException("Error closing Tarfile");
-}
-
-void Tarfile::write_object(int id, const char *data, size_t len)
-{
-    char buf[64];
-    sprintf(buf, "%08x", id);
-    string path = segment_name + "/" + buf;
-
-    internal_write_object(path, data, len);
-
-    // Compute a checksum for the data block, which will be stored at the end
-    // of the TAR file.
-    SHA1Checksum hash;
-    hash.process(data, len);
-    sprintf(buf, "%08x", id);
-    checksums << buf << " " << hash.checksum_str() << "\n";
-}
-
-void Tarfile::internal_write_object(const string &path,
-                                    const char *data, size_t len)
-{
-    memset(&t->th_buf, 0, sizeof(struct tar_header));
-
-    th_set_type(t, S_IFREG | 0600);
-    th_set_user(t, 0);
-    th_set_group(t, 0);
-    th_set_mode(t, 0600);
-    th_set_size(t, len);
-    th_set_mtime(t, time(NULL));
-    th_set_path(t, const_cast<char *>(path.c_str()));
-    th_finish(t);
-
-    if (th_write(t) != 0)
-        throw IOException("Error writing tar header");
-
-    size += T_BLOCKSIZE;
-
-    if (len == 0)
-        return;
-
-    size_t blocks = (len + T_BLOCKSIZE - 1) / T_BLOCKSIZE;
-    size_t padding = blocks * T_BLOCKSIZE - len;
-
-    for (size_t i = 0; i < blocks - 1; i++) {
-        if (tar_block_write(t, &data[i * T_BLOCKSIZE]) == -1)
-            throw IOException("Error writing tar block");
-    }
-
-    char block[T_BLOCKSIZE];
-    memset(block, 0, sizeof(block));
-    memcpy(block, &data[T_BLOCKSIZE * (blocks - 1)], T_BLOCKSIZE - padding);
-    if (tar_block_write(t, block) == -1)
-        throw IOException("Error writing final tar block");
-
-    size += blocks * T_BLOCKSIZE;
-}
-
-static const size_t SEGMENT_SIZE = 4 * 1024 * 1024;
-
-string TarSegmentStore::write_object(const char *data, size_t len, const
-                                     std::string &group,
-                                     const std::list<std::string> &refs)
-{
-    struct segment_info *segment;
-
-    // Find the segment into which the object should be written, looking up by
-    // group.  If no segment exists yet, create one.
-    if (segments.find(group) == segments.end()) {
-        segment = new segment_info;
-
-        uint8_t uuid[16];
-        char uuid_buf[40];
-        uuid_generate(uuid);
-        uuid_unparse_lower(uuid, uuid_buf);
-        segment->name = uuid_buf;
-
-        string filename = path + "/" + segment->name + ".tar";
-        segment->file = new Tarfile(filename, segment->name);
-
-        segment->count = 0;
-
-        segments[group] = segment;
-    } else {
-        segment = segments[group];
-    }
-
-    int id = segment->count;
-    char id_buf[64];
-    sprintf(id_buf, "%08x", id);
-
-    segment->file->write_object(id, data, len);
-    segment->count++;
-
-    string full_name = segment->name + "/" + id_buf;
-
-    // Store any dependencies this object has on other segments, so they can be
-    // written when the segment is closed.
-    for (list<string>::const_iterator i = refs.begin(); i != refs.end(); ++i) {
-        segment->refs.insert(*i);
-    }
-
-    // If this segment meets or exceeds the size target, close it so that
-    // future objects will go into a new segment.
-    if (segment->file->size_estimate() >= SEGMENT_SIZE)
-        close_segment(group);
-
-    return full_name;
-}
-
-void TarSegmentStore::sync()
-{
-    while (!segments.empty())
-        close_segment(segments.begin()->first);
-}
-
-void TarSegmentStore::close_segment(const string &group)
-{
-    struct segment_info *segment = segments[group];
-    fprintf(stderr, "Closing segment group %s (%s)\n",
-            group.c_str(), segment->name.c_str());
-
-    string reflist;
-    for (set<string>::iterator i = segment->refs.begin();
-         i != segment->refs.end(); ++i) {
-        reflist += *i + "\n";
-    }
-    segment->file->internal_write_object(segment->name + "/references",
-                                         reflist.data(), reflist.size());
-
-    delete segment->file;
-    segments.erase(segments.find(group));
-    delete segment;
-}
-
-string TarSegmentStore::object_reference_to_segment(const string &object)
-{
-    return object;
-}
diff --git a/tarstore.h b/tarstore.h
deleted file mode 100644
index 6acee7f..0000000
--- a/tarstore.h
+++ /dev/null
@@ -1,104 +0,0 @@
-/* LBS: An LFS-inspired filesystem backup system
- * Copyright (C) 2006  Michael Vrable
- *
- * Backup data is stored in a collection of objects, which are grouped together
- * into segments for storage purposes.  This implementation of the object store
- * is built on top of libtar, and represents segments as TAR files and objects
- * as files within them. */
-
-#ifndef _LBS_TARSTORE_H
-#define _LBS_TARSTORE_H
-
-#include <stdint.h>
-#include <libtar.h>
-
-#include <list>
-#include <map>
-#include <set>
-#include <string>
-#include <iostream>
-#include <sstream>
-
-#include "sha1.h"
-
-/* In memory datatype to represent key/value pairs of information, such as file
- * metadata.  Currently implemented as map<string, string>. */
-typedef std::map<std::string, std::string> dictionary;
-
-/* IOException will be thrown if an error occurs while reading or writing in
- * one of the I/O wrappers.  Depending upon the context; this may be fatal or
- * not--typically, errors reading/writing the store will be serious, but errors
- * reading an individual file are less so. */
-class IOException : public std::exception {
-private:
-    std::string error;
-public:
-    explicit IOException(const std::string &err) { error = err; }
-    virtual ~IOException() throw () { }
-    std::string getError() const { return error; }
-};
-
-/* A simple wrapper around a single TAR file to represent a segment.  Objects
- * may only be written out all at once, since the tar header must be written
- * first; incremental writing is not supported. */
-class Tarfile {
-public:
-    Tarfile(const std::string &path, const std::string &segment);
-    ~Tarfile();
-
-    void write_object(int id, const char *data, size_t len);
-
-    // Return an estimate of the size of the file.
-    size_t size_estimate() { return size; }
-
-    void internal_write_object(const std::string &path,
-                               const char *data, size_t len);
-
-private:
-    size_t size;
-    std::string segment_name;
-    std::ostringstream checksums;
-    TAR *t;
-};
-
-class TarSegmentStore {
-public:
-    // New segments will be stored in the given directory.
-    TarSegmentStore(const std::string &path) { this->path = path; }
-    ~TarSegmentStore() { sync(); }
-
-    // Writes an object to segment in the store, and returns the name
-    // (segment/object) to refer to it.  The optional parameter group can be
-    // used to control object placement; objects with different group
-    // parameters are kept in separate segments.
-    std::string write_object(const char *data, size_t len,
-                             const std::string &group = "",
-                             const std::list<std::string> &refs = norefs);
-
-    // Ensure all segments have been fully written.
-    void sync();
-
-private:
-    struct segment_info {
-        Tarfile *file;
-        std::string name;           // UUID
-        std::set<std::string> refs; // Other segments this one refers to
-        int count;                  // Objects written to this segment
-    };
-
-    std::string path;
-    std::map<std::string, struct segment_info *> segments;
-
-    // An empty list which can be used as an argument to write_object to
-    // indicate that this object depends on no others.
-    static std::list<std::string> norefs;
-
-    // Ensure that all segments in the given group have been fully written.
-    void close_segment(const std::string &group);
-
-    // Parse an object reference string and return just the segment name
-    // portion.
-    std::string object_reference_to_segment(const std::string &object);
-};
-
-#endif // _LBS_TARSTORE_H