`pkg-config --cflags $(PACKAGES)`
LDFLAGS=-g -pg -ltar `pkg-config --libs $(PACKAGES)`
-SRCS=format.cc scandir.cc sha1.cc store.cc tarstore.cc
+SRCS=format.cc scandir.cc sha1.cc tarstore.cc
OBJS=$(SRCS:.cc=.o)
scandir : $(OBJS)
#include <sstream>
#include "format.h"
-#include "store.h"
#include "tarstore.h"
#include "sha1.h"
+++ /dev/null
-/* 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 file provides interfaces for
- * reading and writing objects and segments. */
-
-#include <assert.h>
-#include <uuid/uuid.h>
-
-#include "store.h"
-
-using std::string;
-
-OutputStream::OutputStream()
- : bytes_written(0)
-{
-}
-
-void OutputStream::write(const void *data, size_t len)
-{
- write_internal(data, len);
- bytes_written += len;
-}
-
-void OutputStream::write_u8(uint8_t val)
-{
- write(&val, 1);
-}
-
-void OutputStream::write_u16(uint16_t val)
-{
- unsigned char buf[2];
-
- buf[0] = val & 0xff;
- buf[1] = (val >> 8) & 0xff;
- write(buf, 2);
-}
-
-void OutputStream::write_u32(uint32_t val)
-{
- unsigned char buf[4];
-
- buf[0] = val & 0xff;
- buf[1] = (val >> 8) & 0xff;
- buf[2] = (val >> 16) & 0xff;
- buf[3] = (val >> 24) & 0xff;
- write(buf, 4);
-}
-
-void OutputStream::write_u64(uint64_t val)
-{
- unsigned char buf[8];
-
- buf[0] = val & 0xff;
- buf[1] = (val >> 8) & 0xff;
- buf[2] = (val >> 16) & 0xff;
- buf[3] = (val >> 24) & 0xff;
- buf[4] = (val >> 32) & 0xff;
- buf[5] = (val >> 40) & 0xff;
- buf[6] = (val >> 48) & 0xff;
- buf[7] = (val >> 56) & 0xff;
- write(buf, 8);
-}
-
-/* Writes an integer to an output stream using a variable-sized representation:
- * seven bits are written at a time (little-endian), and the eigth bit of each
- * byte is set if more data follows. */
-void OutputStream::write_varint(uint64_t val)
-{
- do {
- uint8_t remainder = (val & 0x7f);
- val >>= 7;
- if (val)
- remainder |= 0x80;
- write_u8(remainder);
- } while (val);
-}
-
-void OutputStream::write_uuid(const struct uuid &u)
-{
- write(u.bytes, 16);
-}
-
-/* Write an arbitrary string by first writing out the length, followed by the
- * data itself. */
-void OutputStream::write_string(const string &s)
-{
- size_t len = s.length();
- write_varint(len);
- write(s.data(), len);
-}
-
-void OutputStream::write_dictionary(const dictionary &d)
-{
- size_t size = d.size();
- size_t written = 0;
-
- write_varint(size);
-
- for (dictionary::const_iterator i = d.begin(); i != d.end(); ++i) {
- write_string(i->first);
- write_string(i->second);
- written++;
- }
-
- assert(written == size);
-}
-
-StringOutputStream::StringOutputStream()
- : buf(std::ios_base::out)
-{
-}
-
-void StringOutputStream::write_internal(const void *data, size_t len)
-{
- buf.write((const char *)data, len);
- if (!buf.good())
- throw IOException("error writing to StringOutputStream");
-}
-
-FileOutputStream::FileOutputStream(FILE *file)
-{
- f = file;
-}
-
-FileOutputStream::~FileOutputStream()
-{
- fclose(f);
-}
-
-void FileOutputStream::write_internal(const void *data, size_t len)
-{
- size_t res;
-
- res = fwrite(data, 1, len, f);
- if (res != len) {
- throw IOException("write error");
- }
-}
-
-WrapperOutputStream::WrapperOutputStream(OutputStream &o)
- : real(o)
-{
-}
-
-void WrapperOutputStream::write_internal(const void *data, size_t len)
-{
- real.write(data, len);
-}
-
-/* Provide checksumming of a data stream. */
-ChecksumOutputStream::ChecksumOutputStream(OutputStream &o)
- : real(o)
-{
-}
-
-void ChecksumOutputStream::write_internal(const void *data, size_t len)
-{
- real.write(data, len);
- csum.process(data, len);
-}
-
-const uint8_t *ChecksumOutputStream::finish_and_checksum()
-{
- return csum.checksum();
-}
-
-/* Utility functions, for encoding data types to strings. */
-string encode_u16(uint16_t val)
-{
- StringOutputStream s;
- s.write_u16(val);
- return s.contents();
-}
-
-string encode_u32(uint32_t val)
-{
- StringOutputStream s;
- s.write_u32(val);
- return s.contents();
-}
-
-string encode_u64(uint64_t val)
-{
- StringOutputStream s;
- s.write_u64(val);
- return s.contents();
-}
-
-string encode_objref(const struct uuid &segment, uint32_t object)
-{
- StringOutputStream s;
- s.write_uuid(segment);
- s.write_u32(object);
- return s.contents();
-}
-
-SegmentWriter::SegmentWriter(OutputStream *output, struct uuid u)
- : raw_out(output),
- id(u),
- object_stream(NULL)
-{
- /* All output data will be checksummed except the very last few bytes,
- * which are the checksum itself. */
- out = new ChecksumOutputStream(*raw_out);
-
- /* Write out the segment header first. */
- static const char signature[] = "LBSSEG0\n";
- out->write(signature, strlen(signature));
- out->write_uuid(id);
-}
-
-SegmentWriter::~SegmentWriter()
-{
- if (object_stream)
- finish_object();
-
- // Write out the object table which gives the sizes and locations of all
- // objects, and then add the trailing signature, which indicates the end of
- // the segment and gives the offset of the object table.
- int64_t index_offset = out->get_pos();
-
- for (object_table::const_iterator i = objects.begin();
- i != objects.end(); ++i) {
- out->write_s64(i->offset);
- out->write_s64(i->size);
- out->write(i->type, sizeof(i->type));
- }
-
- static const char signature2[] = "LBSEND";
- out->write(signature2, strlen(signature2));
- out->write_s64(index_offset);
- out->write_u32(objects.size());
-
- /* Finally, append a checksum to the end of the file, so that its integrity
- * (against accidental, not malicious, corruption) can be verified. */
- const uint8_t *csum = out->finish_and_checksum();
- raw_out->write(csum, out->checksum_size());
-
- /* The SegmentWriter takes ownership of the OutputStream it is writing to,
- * and destroys it automatically when done with the segment. */
- delete out;
- delete raw_out;
-}
-
-OutputStream *SegmentWriter::new_object(int *id, const char *type)
-{
- if (object_stream)
- finish_object();
-
- if (id != NULL)
- *id = objects.size();
-
- struct index_info info;
- info.offset = out->get_pos();
- info.size = -1; // Will be filled in when object is finished
- strncpy(info.type, type, sizeof(info.type));
- objects.push_back(info);
-
- object_stream = new WrapperOutputStream(*out);
- return object_stream;
-}
-
-void SegmentWriter::finish_object()
-{
- assert(object_stream != NULL);
-
- // Fill in object size, which could not be stored at start
- objects.back().size = object_stream->get_pos();
-
- delete object_stream;
- object_stream = NULL;
-}
-
-struct uuid SegmentWriter::generate_uuid()
-{
- struct uuid u;
-
- uuid_generate(u.bytes);
-
- return u;
-}
-
-string SegmentWriter::format_uuid(const struct uuid u)
-{
- // A UUID only takes 36 bytes, plus the trailing '\0', so this is safe.
- char buf[40];
-
- uuid_unparse_lower(u.bytes, buf);
-
- return string(buf);
-}
-
-SegmentStore::SegmentStore(const string &path)
- : directory(path)
-{
-}
-
-SegmentWriter *SegmentStore::new_segment()
-{
- struct uuid id = SegmentWriter::generate_uuid();
- string filename = directory + "/" + SegmentWriter::format_uuid(id);
-
- FILE *f = fopen(filename.c_str(), "wb");
- if (f == NULL)
- throw IOException("Unable to open new segment");
-
- return new SegmentWriter(new FileOutputStream(f), id);
-}
-
-SegmentPartitioner::SegmentPartitioner(SegmentStore *s)
- : store(s),
- segment(NULL),
- object(NULL)
-{
- // Default target size is around 1 MB
- target_size = 1024 * 1024;
-}
-
-SegmentPartitioner::~SegmentPartitioner()
-{
- if (segment)
- delete segment;
-}
-
-OutputStream *SegmentPartitioner::new_object(struct uuid *uuid, int *id,
- const char *type)
-{
- if (segment != NULL && segment->get_size() > target_size) {
- delete segment;
- segment = NULL;
- }
-
- if (segment == NULL)
- segment = store->new_segment();
-
- if (uuid != NULL)
- *uuid = segment->get_uuid();
-
- return segment->new_object(id, type);
-}
+++ /dev/null
-/* 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 file provides interfaces for
- * reading and writing objects and segments. */
-
-#ifndef _LBS_STORE_H
-#define _LBS_STORE_H
-
-#include <stdint.h>
-
-#include <exception>
-#include <map>
-#include <string>
-#include <sstream>
-#include <vector>
-
-#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;
-
-/* In-memory representation of a UUID (Universally-Unique Identifier), which is
- * used to name a segment. */
-struct uuid {
- uint8_t bytes[16];
-};
-
-/* 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; }
-};
-
-/* OutputStream is an abstract interface for writing data without seeking.
- * Output could be to a file, to an object within a segment, or even to a
- * memory buffer to help serialize data. */
-class OutputStream {
-public:
- OutputStream();
- virtual ~OutputStream() { }
-
- // Write the given data buffer
- void write(const void *data, size_t len);
-
- // Return the total number of bytes written so far
- int64_t get_pos() const { return bytes_written; }
-
- // Convenience functions for writing other data types. Values are always
- // written out in little-endian order.
- void write_u8(uint8_t val);
- void write_u16(uint16_t val);
- void write_u32(uint32_t val);
- void write_u64(uint64_t val);
-
- void write_s32(int32_t val) { write_u32((uint32_t)val); }
- void write_s64(int64_t val) { write_u64((uint64_t)val); }
-
- void write_varint(uint64_t val);
-
- void write_uuid(const struct uuid &u);
- void write_string(const std::string &s);
- void write_dictionary(const dictionary &d);
-
-protected:
- // Function which actually causes a write: must be overridden by
- // implementation.
- virtual void write_internal(const void *data, size_t len) = 0;
-
-private:
- int64_t bytes_written;
-};
-
-/* An OutputStream implementation which writes data to memory and returns the
- * result as a string. */
-class StringOutputStream : public OutputStream {
-public:
- StringOutputStream();
- std::string contents() const { return buf.str(); }
-
-protected:
- virtual void write_internal(const void *data, size_t len);
-
-private:
- std::stringstream buf;
-};
-
-/* An OutputStream implementation which writes data via the C stdio layer. */
-class FileOutputStream : public OutputStream {
-public:
- explicit FileOutputStream(FILE *file);
- virtual ~FileOutputStream();
-
-protected:
- virtual void write_internal(const void *data, size_t len);
-
-private:
- FILE *f;
-};
-
-/* An OutputStream which is simply sends writes to another OutputStream, but
- * does provide separate tracking of bytes written. */
-class WrapperOutputStream : public OutputStream {
-public:
- explicit WrapperOutputStream(OutputStream &o);
- virtual ~WrapperOutputStream() { }
-
-protected:
- virtual void write_internal(const void *data, size_t len);
-
-private:
- OutputStream ℜ
-};
-
-/* Like WrapperOutputStream, but additionally computes a checksum of data as it
- * is written. */
-class ChecksumOutputStream : public OutputStream {
-public:
- explicit ChecksumOutputStream(OutputStream &o);
- virtual ~ChecksumOutputStream() { }
-
- /* Once a checksum is computed, no further data should be written to the
- * stream. */
- const uint8_t *finish_and_checksum();
- size_t checksum_size() const { return csum.checksum_size(); }
-
-protected:
- virtual void write_internal(const void *data, size_t len);
-
-private:
- OutputStream ℜ
- SHA1Checksum csum;
-};
-
-/* Simple wrappers that encode integers using a StringOutputStream and return
- * the encoded result. */
-std::string encode_u16(uint16_t val);
-std::string encode_u32(uint32_t val);
-std::string encode_u64(uint64_t val);
-std::string encode_objref(const struct uuid &segment, uint32_t object);
-
-/* A class which is used to pack multiple objects into a single segment, with a
- * lookup table to quickly locate each object. Call new_object() to get an
- * OutputStream to which a new object may be written, and optionally
- * finish_object() when finished writing the current object. Only one object
- * may be written to a segment at a time; if multiple objects must be written
- * concurrently, they must be to different segments. */
-class SegmentWriter {
-public:
- SegmentWriter(OutputStream *output, struct uuid u);
- ~SegmentWriter();
-
- struct uuid get_uuid() const { return id; }
-
- // Start writing out a new object to this segment.
- OutputStream *new_object(int *id, const char *type);
- void finish_object();
-
- // Determine size of segment data written out so far.
- size_t get_size() const { return raw_out->get_pos(); }
-
- // Utility functions for generating and formatting UUIDs for display.
- static struct uuid generate_uuid();
- static std::string format_uuid(const struct uuid u);
-
-private:
- struct index_info {
- int64_t offset; // File offset at which object starts
- int64_t size; // Size of object in bytes
- char type[4]; // Object type code
- };
-
- typedef std::vector<struct index_info> object_table;
-
- ChecksumOutputStream *out; // Output stream with checksumming enabled
- OutputStream *raw_out; // Raw output stream, without checksumming
- struct uuid id;
-
- OutputStream *object_stream;
-
- object_table objects;
-};
-
-/* A SegmentStore, as the name suggests, is used to store the contents of many
- * segments. The SegmentStore internally tracks where data should be placed
- * (such as a local directory or remote storage), and allows new segments to be
- * easily created as needed. */
-class SegmentStore {
-public:
- // New segments will be stored in the given directory.
- SegmentStore(const std::string &path);
-
- SegmentWriter *new_segment();
-
-private:
- std::string directory;
-};
-
-/* A SegmentPartitioner helps to divide objects up among a collection of
- * segments to meet a rough size limit per segment. Like a SegmentWriter, only
- * one object should be written at a time; however, multiple
- * SegmentPartitioners can be created using the same base SegmentStore. */
-class SegmentPartitioner {
-public:
- explicit SegmentPartitioner(SegmentStore *s);
- ~SegmentPartitioner();
-
- OutputStream *new_object(struct uuid *uuid, int *id, const char *type);
-
-private:
- size_t target_size;
-
- SegmentStore *store;
- SegmentWriter *segment;
- OutputStream *object;
-};
-
-#endif // _LBS_STORE_H
#include <libtar.h>
#include <list>
+#include <map>
#include <set>
#include <string>
#include <iostream>
#include <sstream>
-#include "store.h"
+#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
projects / cumulus.git / commitdiff