librsync  2.3.2
whole.c
1 /*= -*- c-basic-offset: 4; indent-tabs-mode: nil; -*-
2  *
3  * librsync -- the library for network deltas
4  *
5  * Copyright 2000, 2001, 2014, 2015 by Martin Pool <mbp@sourcefrog.net>
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public License
9  * as published by the Free Software Foundation; either version 2.1 of
10  * the License, or (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful, but
13  * WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with this program; if not, write to the Free Software
19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  */
21 
22  /*=
23  | Is it possible that software is not
24  | like anything else, that it is meant
25  | to be discarded: that the whole point
26  | is to always see it as a soap bubble?
27  | -- Alan Perlis
28  */
29 
30 #include "config.h"
31 #include <assert.h>
32 #include <stdlib.h>
33 #include <stdio.h>
34 #include <string.h>
35 #include "librsync.h"
36 #include "whole.h"
37 #include "sumset.h"
38 #include "job.h"
39 #include "buf.h"
40 
41 /** Whole file IO buffer sizes. */
42 LIBRSYNC_EXPORT int rs_inbuflen = 0, rs_outbuflen = 0;
43 
44 /** Run a job continuously, with input to/from the two specified files.
45  *
46  * The job should already be set up, and must be freed by the caller after
47  * return. If rs_inbuflen or rs_outbuflen are set, they will override the
48  * inbuflen and outbuflen arguments.
49  *
50  * \param in_file - input file, or NULL if there is no input.
51  *
52  * \param out_file - output file, or NULL if there is no output.
53  *
54  * \param inbuflen - recommended input buffer size to use.
55  *
56  * \param outbuflen - recommended output buffer size to use.
57  *
58  * \return RS_DONE if the job completed, or otherwise an error result. */
59 rs_result rs_whole_run(rs_job_t *job, FILE *in_file, FILE *out_file,
60  int inbuflen, int outbuflen)
61 {
62  rs_buffers_t buf;
63  rs_result result;
64  rs_filebuf_t *in_fb = NULL, *out_fb = NULL;
65 
66  /* Override buffer sizes if rs_inbuflen or rs_outbuflen are set. */
67  inbuflen = rs_inbuflen ? rs_inbuflen : inbuflen;
68  outbuflen = rs_outbuflen ? rs_outbuflen : outbuflen;
69  if (in_file)
70  in_fb = rs_filebuf_new(in_file, inbuflen);
71  if (out_file)
72  out_fb = rs_filebuf_new(out_file, outbuflen);
73  result =
74  rs_job_drive(job, &buf, in_fb ? rs_infilebuf_fill : NULL, in_fb,
75  out_fb ? rs_outfilebuf_drain : NULL, out_fb);
76  if (in_fb)
77  rs_filebuf_free(in_fb);
78  if (out_fb)
79  rs_filebuf_free(out_fb);
80  return result;
81 }
82 
83 rs_result rs_sig_file(FILE *old_file, FILE *sig_file, size_t block_len,
84  size_t strong_len, rs_magic_number sig_magic,
85  rs_stats_t *stats)
86 {
87  rs_job_t *job;
88  rs_result r;
89  rs_long_t old_fsize = rs_file_size(old_file);
90 
91  if ((r =
92  rs_sig_args(old_fsize, &sig_magic, &block_len,
93  &strong_len)) != RS_DONE)
94  return r;
95  job = rs_sig_begin(block_len, strong_len, sig_magic);
96  /* Size inbuf for 4 blocks, outbuf for header + 4 blocksums. */
97  r = rs_whole_run(job, old_file, sig_file, 4 * (int)block_len,
98  12 + 4 * (4 + (int)strong_len));
99  if (stats)
100  memcpy(stats, &job->stats, sizeof *stats);
101  rs_job_free(job);
102 
103  return r;
104 }
105 
106 rs_result rs_loadsig_file(FILE *sig_file, rs_signature_t **sumset,
107  rs_stats_t *stats)
108 {
109  rs_job_t *job;
110  rs_result r;
111 
112  job = rs_loadsig_begin(sumset);
113  /* Set filesize used to estimate signature size. */
114  job->sig_fsize = rs_file_size(sig_file);
115  /* Size inbuf for 1024x 16 byte blocksums. */
116  r = rs_whole_run(job, sig_file, NULL, 1024 * 16, 0);
117  if (stats)
118  memcpy(stats, &job->stats, sizeof *stats);
119  rs_job_free(job);
120 
121  return r;
122 }
123 
124 rs_result rs_delta_file(rs_signature_t *sig, FILE *new_file, FILE *delta_file,
125  rs_stats_t *stats)
126 {
127  rs_job_t *job;
128  rs_result r;
129 
130  job = rs_delta_begin(sig);
131  /* Size inbuf for 1 block, outbuf for literal cmd + 4 blocks. */
132  r = rs_whole_run(job, new_file, delta_file, sig->block_len,
133  10 + 4 * sig->block_len);
134  if (stats)
135  memcpy(stats, &job->stats, sizeof *stats);
136  rs_job_free(job);
137  return r;
138 }
139 
140 rs_result rs_patch_file(FILE *basis_file, FILE *delta_file, FILE *new_file,
141  rs_stats_t *stats)
142 {
143  rs_job_t *job;
144  rs_result r;
145 
146  job = rs_patch_begin(rs_file_copy_cb, basis_file);
147  /* Default size inbuf and outbuf 64K. */
148  r = rs_whole_run(job, delta_file, new_file, 64 * 1024, 64 * 1024);
149  if (stats)
150  memcpy(stats, &job->stats, sizeof *stats);
151  rs_job_free(job);
152  return r;
153 }
rs_job_t * rs_delta_begin(rs_signature_t *sig)
Prepare to compute a streaming delta.
Definition: delta.c:386
rs_result rs_job_free(rs_job_t *job)
Deallocate job state.
Definition: job.c:66
rs_result rs_job_drive(rs_job_t *job, rs_buffers_t *buf, rs_driven_cb in_cb, void *in_opaque, rs_driven_cb out_cb, void *out_opaque)
Actively process a job, by making callbacks to fill and empty the buffers until the job is done.
Definition: job.c:152
Public header for librsync.
LIBRSYNC_EXPORT rs_job_t * rs_loadsig_begin(rs_signature_t **)
Read a signature from a file into an rs_signature structure in memory.
Definition: readsums.c:137
LIBRSYNC_EXPORT rs_result rs_sig_file(FILE *old_file, FILE *sig_file, size_t block_len, size_t strong_len, rs_magic_number sig_magic, rs_stats_t *stats)
Generate the signature of a basis file, and write it out to another.
Definition: whole.c:83
LIBRSYNC_EXPORT rs_result rs_sig_args(rs_long_t old_fsize, rs_magic_number *magic, size_t *block_len, size_t *strong_len)
Get or check signature arguments for a given file size.
Definition: sumset.c:114
LIBRSYNC_EXPORT rs_long_t rs_file_size(FILE *file)
Get the size of a file.
Definition: fileutil.c:125
LIBRSYNC_EXPORT rs_result rs_delta_file(rs_signature_t *, FILE *new_file, FILE *delta_file, rs_stats_t *)
Generate a delta between a signature and a new file into a delta file.
Definition: whole.c:124
LIBRSYNC_EXPORT rs_job_t * rs_sig_begin(size_t block_len, size_t strong_len, rs_magic_number sig_magic)
Start generating a signature.
Definition: mksum.c:111
LIBRSYNC_EXPORT rs_result rs_loadsig_file(FILE *sig_file, rs_signature_t **sumset, rs_stats_t *stats)
Load signatures from a signature file into memory.
Definition: whole.c:106
LIBRSYNC_EXPORT rs_result rs_patch_file(FILE *basis_file, FILE *delta_file, FILE *new_file, rs_stats_t *)
Apply a patch, relative to a basis, into a new file.
Definition: whole.c:140
rs_result
Return codes from nonblocking rsync operations.
Definition: librsync.h:180
@ RS_DONE
Completed successfully.
Definition: librsync.h:181
rs_magic_number
A uint32 magic number, emitted in bigendian/network order at the start of librsync files.
Definition: librsync.h:65
LIBRSYNC_EXPORT rs_result rs_file_copy_cb(void *arg, rs_long_t pos, size_t *len, void **buf)
rs_copy_cb that reads from a stdio file.
Definition: fileutil.c:133
LIBRSYNC_EXPORT int rs_inbuflen
Buffer sizes for file IO.
Definition: whole.c:42
LIBRSYNC_EXPORT rs_job_t * rs_patch_begin(rs_copy_cb *copy_cb, void *copy_arg)
Apply a delta to a basis file to recreate the new file.
Definition: patch.c:217
Description of input and output buffers.
Definition: librsync.h:322
Definition: buf.c:50
The contents of this structure are private.
Definition: job.h:26
rs_long_t sig_fsize
The size of the signature file if available.
Definition: job.h:48
rs_stats_t stats
Encoding statistics.
Definition: job.h:72
Signature of a whole file.
Definition: sumset.h:37
int block_len
The block length.
Definition: sumset.h:39
Performance statistics from a librsync encoding or decoding operation.
Definition: librsync.h:210