integrate bsdiff into imgdiff, instead of using subprocess

Integrate the bsdiff code into imgdiff so we can just call it rather
than writing temp files and invoking bsdiff as a subprocess.  When
computing multiple patches from the same source file, we can also save
time by doing some bsdiff preprocessing on the source file only once.

(Note this renames the existing 'bsdiff.c' -- which actually does
patching in applypatch -- to 'bspatch.c', and introduces a new
bsdiff.c linked into imgdiff.)
This commit is contained in:
Doug Zongker 2009-09-25 11:52:00 -07:00
parent 0c44a2a9f3
commit d98e087042
4 changed files with 647 additions and 259 deletions

View file

@ -17,7 +17,7 @@ ifneq ($(TARGET_SIMULATOR),true)
LOCAL_PATH := $(call my-dir) LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS) include $(CLEAR_VARS)
LOCAL_SRC_FILES := applypatch.c bsdiff.c freecache.c imgpatch.c utils.c LOCAL_SRC_FILES := applypatch.c bspatch.c freecache.c imgpatch.c utils.c
LOCAL_MODULE := libapplypatch LOCAL_MODULE := libapplypatch
LOCAL_MODULE_TAGS := eng LOCAL_MODULE_TAGS := eng
LOCAL_C_INCLUDES += external/bzip2 external/zlib bootable/recovery LOCAL_C_INCLUDES += external/bzip2 external/zlib bootable/recovery
@ -47,12 +47,12 @@ include $(BUILD_EXECUTABLE)
include $(CLEAR_VARS) include $(CLEAR_VARS)
LOCAL_SRC_FILES := imgdiff.c utils.c LOCAL_SRC_FILES := imgdiff.c utils.c bsdiff.c
LOCAL_MODULE := imgdiff LOCAL_MODULE := imgdiff
LOCAL_FORCE_STATIC_EXECUTABLE := true LOCAL_FORCE_STATIC_EXECUTABLE := true
LOCAL_MODULE_TAGS := eng LOCAL_MODULE_TAGS := eng
LOCAL_C_INCLUDES += external/zlib LOCAL_C_INCLUDES += external/zlib
LOCAL_STATIC_LIBRARIES += libz LOCAL_STATIC_LIBRARIES += libz libbz
include $(BUILD_HOST_EXECUTABLE) include $(BUILD_HOST_EXECUTABLE)

View file

@ -1,5 +1,5 @@
/* /*
* Copyright (C) 2008 The Android Open Source Project * Copyright (C) 2009 The Android Open Source Project
* *
* Licensed under the Apache License, Version 2.0 (the "License"); * Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License. * you may not use this file except in compliance with the License.
@ -14,239 +14,397 @@
* limitations under the License. * limitations under the License.
*/ */
// This file is a nearly line-for-line copy of bspatch.c from the /*
// bsdiff-4.3 distribution; the primary differences being how the * Most of this code comes from bsdiff.c from the bsdiff-4.3
// input and output data are read and the error handling. Running * distribution, which is:
// applypatch with the -l option will display the bsdiff license */
// notice.
#include <stdio.h> /*-
#include <sys/stat.h> * Copyright 2003-2005 Colin Percival
#include <errno.h> * All rights reserved
#include <unistd.h> *
#include <string.h> * Redistribution and use in source and binary forms, with or without
* modification, are permitted providing that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/types.h>
#include <bzlib.h> #include <bzlib.h>
#include <err.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "mincrypt/sha.h" #define MIN(x,y) (((x)<(y)) ? (x) : (y))
#include "applypatch.h"
void ShowBSDiffLicense() { static void split(off_t *I,off_t *V,off_t start,off_t len,off_t h)
puts("The bsdiff library used herein is:\n" {
"\n" off_t i,j,k,x,tmp,jj,kk;
"Copyright 2003-2005 Colin Percival\n"
"All rights reserved\n" if(len<16) {
"\n" for(k=start;k<start+len;k+=j) {
"Redistribution and use in source and binary forms, with or without\n" j=1;x=V[I[k]+h];
"modification, are permitted providing that the following conditions\n" for(i=1;k+i<start+len;i++) {
"are met:\n" if(V[I[k+i]+h]<x) {
"1. Redistributions of source code must retain the above copyright\n" x=V[I[k+i]+h];
" notice, this list of conditions and the following disclaimer.\n" j=0;
"2. Redistributions in binary form must reproduce the above copyright\n" };
" notice, this list of conditions and the following disclaimer in the\n" if(V[I[k+i]+h]==x) {
" documentation and/or other materials provided with the distribution.\n" tmp=I[k+j];I[k+j]=I[k+i];I[k+i]=tmp;
"\n" j++;
"THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR\n" };
"IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED\n" };
"WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE\n" for(i=0;i<j;i++) V[I[k+i]]=k+j-1;
"ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY\n" if(j==1) I[k]=-1;
"DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL\n" };
"DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS\n" return;
"OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)\n" };
"HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,\n"
"STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING\n" x=V[I[start+len/2]+h];
"IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE\n" jj=0;kk=0;
"POSSIBILITY OF SUCH DAMAGE.\n" for(i=start;i<start+len;i++) {
"\n------------------\n\n" if(V[I[i]+h]<x) jj++;
"This program uses Julian R Seward's \"libbzip2\" library, available\n" if(V[I[i]+h]==x) kk++;
"from http://www.bzip.org/.\n" };
); jj+=start;kk+=jj;
i=start;j=0;k=0;
while(i<jj) {
if(V[I[i]+h]<x) {
i++;
} else if(V[I[i]+h]==x) {
tmp=I[i];I[i]=I[jj+j];I[jj+j]=tmp;
j++;
} else {
tmp=I[i];I[i]=I[kk+k];I[kk+k]=tmp;
k++;
};
};
while(jj+j<kk) {
if(V[I[jj+j]+h]==x) {
j++;
} else {
tmp=I[jj+j];I[jj+j]=I[kk+k];I[kk+k]=tmp;
k++;
};
};
if(jj>start) split(I,V,start,jj-start,h);
for(i=0;i<kk-jj;i++) V[I[jj+i]]=kk-1;
if(jj==kk-1) I[jj]=-1;
if(start+len>kk) split(I,V,kk,start+len-kk,h);
} }
static off_t offtin(u_char *buf) static void qsufsort(off_t *I,off_t *V,u_char *old,off_t oldsize)
{
off_t buckets[256];
off_t i,h,len;
for(i=0;i<256;i++) buckets[i]=0;
for(i=0;i<oldsize;i++) buckets[old[i]]++;
for(i=1;i<256;i++) buckets[i]+=buckets[i-1];
for(i=255;i>0;i--) buckets[i]=buckets[i-1];
buckets[0]=0;
for(i=0;i<oldsize;i++) I[++buckets[old[i]]]=i;
I[0]=oldsize;
for(i=0;i<oldsize;i++) V[i]=buckets[old[i]];
V[oldsize]=0;
for(i=1;i<256;i++) if(buckets[i]==buckets[i-1]+1) I[buckets[i]]=-1;
I[0]=-1;
for(h=1;I[0]!=-(oldsize+1);h+=h) {
len=0;
for(i=0;i<oldsize+1;) {
if(I[i]<0) {
len-=I[i];
i-=I[i];
} else {
if(len) I[i-len]=-len;
len=V[I[i]]+1-i;
split(I,V,i,len,h);
i+=len;
len=0;
};
};
if(len) I[i-len]=-len;
};
for(i=0;i<oldsize+1;i++) I[V[i]]=i;
}
static off_t matchlen(u_char *old,off_t oldsize,u_char *new,off_t newsize)
{
off_t i;
for(i=0;(i<oldsize)&&(i<newsize);i++)
if(old[i]!=new[i]) break;
return i;
}
static off_t search(off_t *I,u_char *old,off_t oldsize,
u_char *new,off_t newsize,off_t st,off_t en,off_t *pos)
{
off_t x,y;
if(en-st<2) {
x=matchlen(old+I[st],oldsize-I[st],new,newsize);
y=matchlen(old+I[en],oldsize-I[en],new,newsize);
if(x>y) {
*pos=I[st];
return x;
} else {
*pos=I[en];
return y;
}
};
x=st+(en-st)/2;
if(memcmp(old+I[x],new,MIN(oldsize-I[x],newsize))<0) {
return search(I,old,oldsize,new,newsize,x,en,pos);
} else {
return search(I,old,oldsize,new,newsize,st,x,pos);
};
}
static void offtout(off_t x,u_char *buf)
{ {
off_t y; off_t y;
y=buf[7]&0x7F; if(x<0) y=-x; else y=x;
y=y*256;y+=buf[6];
y=y*256;y+=buf[5];
y=y*256;y+=buf[4];
y=y*256;y+=buf[3];
y=y*256;y+=buf[2];
y=y*256;y+=buf[1];
y=y*256;y+=buf[0];
if(buf[7]&0x80) y=-y; buf[0]=y%256;y-=buf[0];
y=y/256;buf[1]=y%256;y-=buf[1];
y=y/256;buf[2]=y%256;y-=buf[2];
y=y/256;buf[3]=y%256;y-=buf[3];
y=y/256;buf[4]=y%256;y-=buf[4];
y=y/256;buf[5]=y%256;y-=buf[5];
y=y/256;buf[6]=y%256;y-=buf[6];
y=y/256;buf[7]=y%256;
return y; if(x<0) buf[7]|=0x80;
} }
// This is main() from bsdiff.c, with the following changes:
//
// - old, oldsize, new, newsize are arguments; we don't load this
// data from files. old and new are owned by the caller; we
// don't free them at the end.
//
// - the "I" block of memory is owned by the caller, who passes a
// pointer to *I, which can be NULL. This way if we call
// bsdiff() multiple times with the same 'old' data, we only do
// the qsufsort() step the first time.
//
int bsdiff(u_char* old, off_t oldsize, off_t** IP, u_char* new, off_t newsize,
const char* patch_filename)
{
int fd;
off_t *I;
off_t scan,pos,len;
off_t lastscan,lastpos,lastoffset;
off_t oldscore,scsc;
off_t s,Sf,lenf,Sb,lenb;
off_t overlap,Ss,lens;
off_t i;
off_t dblen,eblen;
u_char *db,*eb;
u_char buf[8];
u_char header[32];
FILE * pf;
BZFILE * pfbz2;
int bz2err;
int ApplyBSDiffPatch(const unsigned char* old_data, ssize_t old_size, if (*IP == NULL) {
const char* patch_filename, ssize_t patch_offset, off_t* V;
SinkFn sink, void* token, SHA_CTX* ctx) { *IP = malloc((oldsize+1) * sizeof(off_t));
V = malloc((oldsize+1) * sizeof(off_t));
qsufsort(*IP, V, old, oldsize);
free(V);
}
I = *IP;
unsigned char* new_data; if(((db=malloc(newsize+1))==NULL) ||
ssize_t new_size; ((eb=malloc(newsize+1))==NULL)) err(1,NULL);
if (ApplyBSDiffPatchMem(old_data, old_size, patch_filename, patch_offset, dblen=0;
&new_data, &new_size) != 0) { eblen=0;
return -1;
}
if (sink(new_data, new_size, token) < new_size) { /* Create the patch file */
fprintf(stderr, "short write of output: %d (%s)\n", errno, strerror(errno)); if ((pf = fopen(patch_filename, "w")) == NULL)
return 1; err(1, "%s", patch_filename);
}
if (ctx) { /* Header is
SHA_update(ctx, new_data, new_size); 0 8 "BSDIFF40"
} 8 8 length of bzip2ed ctrl block
free(new_data); 16 8 length of bzip2ed diff block
24 8 length of new file */
return 0; /* File is
} 0 32 Header
32 ?? Bzip2ed ctrl block
int ApplyBSDiffPatchMem(const unsigned char* old_data, ssize_t old_size, ?? ?? Bzip2ed diff block
const char* patch_filename, ssize_t patch_offset, ?? ?? Bzip2ed extra block */
unsigned char** new_data, ssize_t* new_size) { memcpy(header,"BSDIFF40",8);
offtout(0, header + 8);
FILE* f; offtout(0, header + 16);
if ((f = fopen(patch_filename, "rb")) == NULL) { offtout(newsize, header + 24);
fprintf(stderr, "failed to open patch file\n"); if (fwrite(header, 32, 1, pf) != 1)
return 1; err(1, "fwrite(%s)", patch_filename);
}
/* Compute the differences, writing ctrl as we go */
// File format: if ((pfbz2 = BZ2_bzWriteOpen(&bz2err, pf, 9, 0, 0)) == NULL)
// 0 8 "BSDIFF40" errx(1, "BZ2_bzWriteOpen, bz2err = %d", bz2err);
// 8 8 X scan=0;len=0;
// 16 8 Y lastscan=0;lastpos=0;lastoffset=0;
// 24 8 sizeof(newfile) while(scan<newsize) {
// 32 X bzip2(control block) oldscore=0;
// 32+X Y bzip2(diff block)
// 32+X+Y ??? bzip2(extra block) for(scsc=scan+=len;scan<newsize;scan++) {
// with control block a set of triples (x,y,z) meaning "add x bytes len=search(I,old,oldsize,new+scan,newsize-scan,
// from oldfile to x bytes from the diff block; copy y bytes from the 0,oldsize,&pos);
// extra block; seek forwards in oldfile by z bytes".
for(;scsc<scan+len;scsc++)
fseek(f, patch_offset, SEEK_SET); if((scsc+lastoffset<oldsize) &&
(old[scsc+lastoffset] == new[scsc]))
unsigned char header[32]; oldscore++;
if (fread(header, 1, 32, f) < 32) {
fprintf(stderr, "failed to read patch file header\n"); if(((len==oldscore) && (len!=0)) ||
return 1; (len>oldscore+8)) break;
}
if((scan+lastoffset<oldsize) &&
if (memcmp(header, "BSDIFF40", 8) != 0) { (old[scan+lastoffset] == new[scan]))
fprintf(stderr, "corrupt bsdiff patch file header (magic number)\n"); oldscore--;
return 1; };
}
if((len!=oldscore) || (scan==newsize)) {
ssize_t ctrl_len, data_len; s=0;Sf=0;lenf=0;
ctrl_len = offtin(header+8); for(i=0;(lastscan+i<scan)&&(lastpos+i<oldsize);) {
data_len = offtin(header+16); if(old[lastpos+i]==new[lastscan+i]) s++;
*new_size = offtin(header+24); i++;
if(s*2-i>Sf*2-lenf) { Sf=s; lenf=i; };
if (ctrl_len < 0 || data_len < 0 || *new_size < 0) { };
fprintf(stderr, "corrupt patch file header (data lengths)\n");
return 1; lenb=0;
} if(scan<newsize) {
s=0;Sb=0;
fclose(f); for(i=1;(scan>=lastscan+i)&&(pos>=i);i++) {
if(old[pos-i]==new[scan-i]) s++;
int bzerr; if(s*2-i>Sb*2-lenb) { Sb=s; lenb=i; };
};
#define OPEN_AT(f, bzf, offset) \ };
FILE* f; \
BZFILE* bzf; \ if(lastscan+lenf>scan-lenb) {
if ((f = fopen(patch_filename, "rb")) == NULL) { \ overlap=(lastscan+lenf)-(scan-lenb);
fprintf(stderr, "failed to open patch file\n"); \ s=0;Ss=0;lens=0;
return 1; \ for(i=0;i<overlap;i++) {
} \ if(new[lastscan+lenf-overlap+i]==
if (fseeko(f, offset+patch_offset, SEEK_SET)) { \ old[lastpos+lenf-overlap+i]) s++;
fprintf(stderr, "failed to seek in patch file\n"); \ if(new[scan-lenb+i]==
return 1; \ old[pos-lenb+i]) s--;
} \ if(s>Ss) { Ss=s; lens=i+1; };
if ((bzf = BZ2_bzReadOpen(&bzerr, f, 0, 0, NULL, 0)) == NULL) { \ };
fprintf(stderr, "failed to bzReadOpen in patch file (%d)\n", bzerr); \
return 1; \ lenf+=lens-overlap;
} lenb-=lens;
};
OPEN_AT(cpf, cpfbz2, 32);
OPEN_AT(dpf, dpfbz2, 32+ctrl_len); for(i=0;i<lenf;i++)
OPEN_AT(epf, epfbz2, 32+ctrl_len+data_len); db[dblen+i]=new[lastscan+i]-old[lastpos+i];
for(i=0;i<(scan-lenb)-(lastscan+lenf);i++)
#undef OPEN_AT eb[eblen+i]=new[lastscan+lenf+i];
*new_data = malloc(*new_size); dblen+=lenf;
if (*new_data == NULL) { eblen+=(scan-lenb)-(lastscan+lenf);
fprintf(stderr, "failed to allocate %d bytes of memory for output file\n",
(int)*new_size); offtout(lenf,buf);
return 1; BZ2_bzWrite(&bz2err, pfbz2, buf, 8);
} if (bz2err != BZ_OK)
errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
off_t oldpos = 0, newpos = 0;
off_t ctrl[3]; offtout((scan-lenb)-(lastscan+lenf),buf);
off_t len_read; BZ2_bzWrite(&bz2err, pfbz2, buf, 8);
int i; if (bz2err != BZ_OK)
unsigned char buf[8]; errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
while (newpos < *new_size) {
// Read control data offtout((pos-lenb)-(lastpos+lenf),buf);
for (i = 0; i < 3; ++i) { BZ2_bzWrite(&bz2err, pfbz2, buf, 8);
len_read = BZ2_bzRead(&bzerr, cpfbz2, buf, 8); if (bz2err != BZ_OK)
if (len_read < 8 || !(bzerr == BZ_OK || bzerr == BZ_STREAM_END)) { errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
fprintf(stderr, "corrupt patch (read control)\n");
return 1; lastscan=scan-lenb;
} lastpos=pos-lenb;
ctrl[i] = offtin(buf); lastoffset=pos-scan;
} };
};
// Sanity check BZ2_bzWriteClose(&bz2err, pfbz2, 0, NULL, NULL);
if (newpos + ctrl[0] > *new_size) { if (bz2err != BZ_OK)
fprintf(stderr, "corrupt patch (new file overrun)\n"); errx(1, "BZ2_bzWriteClose, bz2err = %d", bz2err);
return 1;
} /* Compute size of compressed ctrl data */
if ((len = ftello(pf)) == -1)
// Read diff string err(1, "ftello");
len_read = BZ2_bzRead(&bzerr, dpfbz2, *new_data + newpos, ctrl[0]); offtout(len-32, header + 8);
if (len_read < ctrl[0] || !(bzerr == BZ_OK || bzerr == BZ_STREAM_END)) {
fprintf(stderr, "corrupt patch (read diff)\n"); /* Write compressed diff data */
return 1; if ((pfbz2 = BZ2_bzWriteOpen(&bz2err, pf, 9, 0, 0)) == NULL)
} errx(1, "BZ2_bzWriteOpen, bz2err = %d", bz2err);
BZ2_bzWrite(&bz2err, pfbz2, db, dblen);
// Add old data to diff string if (bz2err != BZ_OK)
for (i = 0; i < ctrl[0]; ++i) { errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
if ((oldpos+i >= 0) && (oldpos+i < old_size)) { BZ2_bzWriteClose(&bz2err, pfbz2, 0, NULL, NULL);
(*new_data)[newpos+i] += old_data[oldpos+i]; if (bz2err != BZ_OK)
} errx(1, "BZ2_bzWriteClose, bz2err = %d", bz2err);
}
/* Compute size of compressed diff data */
// Adjust pointers if ((newsize = ftello(pf)) == -1)
newpos += ctrl[0]; err(1, "ftello");
oldpos += ctrl[0]; offtout(newsize - len, header + 16);
// Sanity check /* Write compressed extra data */
if (newpos + ctrl[1] > *new_size) { if ((pfbz2 = BZ2_bzWriteOpen(&bz2err, pf, 9, 0, 0)) == NULL)
fprintf(stderr, "corrupt patch (new file overrun)\n"); errx(1, "BZ2_bzWriteOpen, bz2err = %d", bz2err);
return 1; BZ2_bzWrite(&bz2err, pfbz2, eb, eblen);
} if (bz2err != BZ_OK)
errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
// Read extra string BZ2_bzWriteClose(&bz2err, pfbz2, 0, NULL, NULL);
len_read = BZ2_bzRead(&bzerr, epfbz2, *new_data + newpos, ctrl[1]); if (bz2err != BZ_OK)
if (len_read < ctrl[1] || !(bzerr == BZ_OK || bzerr == BZ_STREAM_END)) { errx(1, "BZ2_bzWriteClose, bz2err = %d", bz2err);
fprintf(stderr, "corrupt patch (read extra)\n");
return 1; /* Seek to the beginning, write the header, and close the file */
} if (fseeko(pf, 0, SEEK_SET))
err(1, "fseeko");
// Adjust pointers if (fwrite(header, 32, 1, pf) != 1)
newpos += ctrl[1]; err(1, "fwrite(%s)", patch_filename);
oldpos += ctrl[2]; if (fclose(pf))
} err(1, "fclose");
BZ2_bzReadClose(&bzerr, cpfbz2); /* Free the memory we used */
BZ2_bzReadClose(&bzerr, dpfbz2); free(db);
BZ2_bzReadClose(&bzerr, epfbz2); free(eb);
fclose(cpf);
fclose(dpf);
fclose(epf);
return 0; return 0;
} }

252
tools/applypatch/bspatch.c Normal file
View file

@ -0,0 +1,252 @@
/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
// This file is a nearly line-for-line copy of bspatch.c from the
// bsdiff-4.3 distribution; the primary differences being how the
// input and output data are read and the error handling. Running
// applypatch with the -l option will display the bsdiff license
// notice.
#include <stdio.h>
#include <sys/stat.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>
#include <bzlib.h>
#include "mincrypt/sha.h"
#include "applypatch.h"
void ShowBSDiffLicense() {
puts("The bsdiff library used herein is:\n"
"\n"
"Copyright 2003-2005 Colin Percival\n"
"All rights reserved\n"
"\n"
"Redistribution and use in source and binary forms, with or without\n"
"modification, are permitted providing that the following conditions\n"
"are met:\n"
"1. Redistributions of source code must retain the above copyright\n"
" notice, this list of conditions and the following disclaimer.\n"
"2. Redistributions in binary form must reproduce the above copyright\n"
" notice, this list of conditions and the following disclaimer in the\n"
" documentation and/or other materials provided with the distribution.\n"
"\n"
"THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR\n"
"IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED\n"
"WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE\n"
"ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY\n"
"DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL\n"
"DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS\n"
"OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)\n"
"HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,\n"
"STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING\n"
"IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE\n"
"POSSIBILITY OF SUCH DAMAGE.\n"
"\n------------------\n\n"
"This program uses Julian R Seward's \"libbzip2\" library, available\n"
"from http://www.bzip.org/.\n"
);
}
static off_t offtin(u_char *buf)
{
off_t y;
y=buf[7]&0x7F;
y=y*256;y+=buf[6];
y=y*256;y+=buf[5];
y=y*256;y+=buf[4];
y=y*256;y+=buf[3];
y=y*256;y+=buf[2];
y=y*256;y+=buf[1];
y=y*256;y+=buf[0];
if(buf[7]&0x80) y=-y;
return y;
}
int ApplyBSDiffPatch(const unsigned char* old_data, ssize_t old_size,
const char* patch_filename, ssize_t patch_offset,
SinkFn sink, void* token, SHA_CTX* ctx) {
unsigned char* new_data;
ssize_t new_size;
if (ApplyBSDiffPatchMem(old_data, old_size, patch_filename, patch_offset,
&new_data, &new_size) != 0) {
return -1;
}
if (sink(new_data, new_size, token) < new_size) {
fprintf(stderr, "short write of output: %d (%s)\n", errno, strerror(errno));
return 1;
}
if (ctx) {
SHA_update(ctx, new_data, new_size);
}
free(new_data);
return 0;
}
int ApplyBSDiffPatchMem(const unsigned char* old_data, ssize_t old_size,
const char* patch_filename, ssize_t patch_offset,
unsigned char** new_data, ssize_t* new_size) {
FILE* f;
if ((f = fopen(patch_filename, "rb")) == NULL) {
fprintf(stderr, "failed to open patch file\n");
return 1;
}
// File format:
// 0 8 "BSDIFF40"
// 8 8 X
// 16 8 Y
// 24 8 sizeof(newfile)
// 32 X bzip2(control block)
// 32+X Y bzip2(diff block)
// 32+X+Y ??? bzip2(extra block)
// with control block a set of triples (x,y,z) meaning "add x bytes
// from oldfile to x bytes from the diff block; copy y bytes from the
// extra block; seek forwards in oldfile by z bytes".
fseek(f, patch_offset, SEEK_SET);
unsigned char header[32];
if (fread(header, 1, 32, f) < 32) {
fprintf(stderr, "failed to read patch file header\n");
return 1;
}
if (memcmp(header, "BSDIFF40", 8) != 0) {
fprintf(stderr, "corrupt bsdiff patch file header (magic number)\n");
return 1;
}
ssize_t ctrl_len, data_len;
ctrl_len = offtin(header+8);
data_len = offtin(header+16);
*new_size = offtin(header+24);
if (ctrl_len < 0 || data_len < 0 || *new_size < 0) {
fprintf(stderr, "corrupt patch file header (data lengths)\n");
return 1;
}
fclose(f);
int bzerr;
#define OPEN_AT(f, bzf, offset) \
FILE* f; \
BZFILE* bzf; \
if ((f = fopen(patch_filename, "rb")) == NULL) { \
fprintf(stderr, "failed to open patch file\n"); \
return 1; \
} \
if (fseeko(f, offset+patch_offset, SEEK_SET)) { \
fprintf(stderr, "failed to seek in patch file\n"); \
return 1; \
} \
if ((bzf = BZ2_bzReadOpen(&bzerr, f, 0, 0, NULL, 0)) == NULL) { \
fprintf(stderr, "failed to bzReadOpen in patch file (%d)\n", bzerr); \
return 1; \
}
OPEN_AT(cpf, cpfbz2, 32);
OPEN_AT(dpf, dpfbz2, 32+ctrl_len);
OPEN_AT(epf, epfbz2, 32+ctrl_len+data_len);
#undef OPEN_AT
*new_data = malloc(*new_size);
if (*new_data == NULL) {
fprintf(stderr, "failed to allocate %d bytes of memory for output file\n",
(int)*new_size);
return 1;
}
off_t oldpos = 0, newpos = 0;
off_t ctrl[3];
off_t len_read;
int i;
unsigned char buf[8];
while (newpos < *new_size) {
// Read control data
for (i = 0; i < 3; ++i) {
len_read = BZ2_bzRead(&bzerr, cpfbz2, buf, 8);
if (len_read < 8 || !(bzerr == BZ_OK || bzerr == BZ_STREAM_END)) {
fprintf(stderr, "corrupt patch (read control)\n");
return 1;
}
ctrl[i] = offtin(buf);
}
// Sanity check
if (newpos + ctrl[0] > *new_size) {
fprintf(stderr, "corrupt patch (new file overrun)\n");
return 1;
}
// Read diff string
len_read = BZ2_bzRead(&bzerr, dpfbz2, *new_data + newpos, ctrl[0]);
if (len_read < ctrl[0] || !(bzerr == BZ_OK || bzerr == BZ_STREAM_END)) {
fprintf(stderr, "corrupt patch (read diff)\n");
return 1;
}
// Add old data to diff string
for (i = 0; i < ctrl[0]; ++i) {
if ((oldpos+i >= 0) && (oldpos+i < old_size)) {
(*new_data)[newpos+i] += old_data[oldpos+i];
}
}
// Adjust pointers
newpos += ctrl[0];
oldpos += ctrl[0];
// Sanity check
if (newpos + ctrl[1] > *new_size) {
fprintf(stderr, "corrupt patch (new file overrun)\n");
return 1;
}
// Read extra string
len_read = BZ2_bzRead(&bzerr, epfbz2, *new_data + newpos, ctrl[1]);
if (len_read < ctrl[1] || !(bzerr == BZ_OK || bzerr == BZ_STREAM_END)) {
fprintf(stderr, "corrupt patch (read extra)\n");
return 1;
}
// Adjust pointers
newpos += ctrl[1];
oldpos += ctrl[2];
}
BZ2_bzReadClose(&bzerr, cpfbz2);
BZ2_bzReadClose(&bzerr, dpfbz2);
BZ2_bzReadClose(&bzerr, epfbz2);
fclose(cpf);
fclose(dpf);
fclose(epf);
return 0;
}

View file

@ -134,6 +134,8 @@ typedef struct {
size_t source_start; size_t source_start;
size_t source_len; size_t source_len;
off_t* I; // used by bsdiff
// --- for CHUNK_DEFLATE chunks only: --- // --- for CHUNK_DEFLATE chunks only: ---
// original (compressed) deflate data // original (compressed) deflate data
@ -167,6 +169,10 @@ static int fileentry_compare(const void* a, const void* b) {
} }
} }
// from bsdiff.c
int bsdiff(u_char* old, off_t oldsize, off_t** IP, u_char* new, off_t newsize,
const char* patch_filename);
unsigned char* ReadZip(const char* filename, unsigned char* ReadZip(const char* filename,
int* num_chunks, ImageChunk** chunks, int* num_chunks, ImageChunk** chunks,
int include_pseudo_chunk) { int include_pseudo_chunk) {
@ -278,6 +284,7 @@ unsigned char* ReadZip(const char* filename,
curr->len = st.st_size; curr->len = st.st_size;
curr->data = img; curr->data = img;
curr->filename = NULL; curr->filename = NULL;
curr->I = NULL;
++curr; ++curr;
++*num_chunks; ++*num_chunks;
} }
@ -292,6 +299,7 @@ unsigned char* ReadZip(const char* filename,
curr->deflate_len = temp_entries[nextentry].deflate_len; curr->deflate_len = temp_entries[nextentry].deflate_len;
curr->deflate_data = img + pos; curr->deflate_data = img + pos;
curr->filename = temp_entries[nextentry].filename; curr->filename = temp_entries[nextentry].filename;
curr->I = NULL;
curr->len = temp_entries[nextentry].uncomp_len; curr->len = temp_entries[nextentry].uncomp_len;
curr->data = malloc(curr->len); curr->data = malloc(curr->len);
@ -336,6 +344,7 @@ unsigned char* ReadZip(const char* filename,
} }
curr->data = img + pos; curr->data = img + pos;
curr->filename = NULL; curr->filename = NULL;
curr->I = NULL;
pos += curr->len; pos += curr->len;
++*num_chunks; ++*num_chunks;
@ -400,6 +409,7 @@ unsigned char* ReadImage(const char* filename,
curr->type = CHUNK_NORMAL; curr->type = CHUNK_NORMAL;
curr->len = GZIP_HEADER_LEN; curr->len = GZIP_HEADER_LEN;
curr->data = p; curr->data = p;
curr->I = NULL;
pos += curr->len; pos += curr->len;
p += curr->len; p += curr->len;
@ -407,6 +417,7 @@ unsigned char* ReadImage(const char* filename,
curr->type = CHUNK_DEFLATE; curr->type = CHUNK_DEFLATE;
curr->filename = NULL; curr->filename = NULL;
curr->I = NULL;
// We must decompress this chunk in order to discover where it // We must decompress this chunk in order to discover where it
// ends, and so we can put the uncompressed data and its length // ends, and so we can put the uncompressed data and its length
@ -452,6 +463,7 @@ unsigned char* ReadImage(const char* filename,
curr->start = pos; curr->start = pos;
curr->len = GZIP_FOOTER_LEN; curr->len = GZIP_FOOTER_LEN;
curr->data = img+pos; curr->data = img+pos;
curr->I = NULL;
pos += curr->len; pos += curr->len;
p += curr->len; p += curr->len;
@ -475,6 +487,7 @@ unsigned char* ReadImage(const char* filename,
*chunks = realloc(*chunks, *num_chunks * sizeof(ImageChunk)); *chunks = realloc(*chunks, *num_chunks * sizeof(ImageChunk));
ImageChunk* curr = *chunks + (*num_chunks-1); ImageChunk* curr = *chunks + (*num_chunks-1);
curr->start = pos; curr->start = pos;
curr->I = NULL;
// 'pos' is not the offset of the start of a gzip chunk, so scan // 'pos' is not the offset of the start of a gzip chunk, so scan
// forward until we find a gzip header. // forward until we find a gzip header.
@ -591,43 +604,12 @@ unsigned char* MakePatch(ImageChunk* src, ImageChunk* tgt, size_t* size) {
} }
} }
char stemp[] = "/tmp/imgdiff-src-XXXXXX";
char ttemp[] = "/tmp/imgdiff-tgt-XXXXXX";
char ptemp[] = "/tmp/imgdiff-patch-XXXXXX"; char ptemp[] = "/tmp/imgdiff-patch-XXXXXX";
mkstemp(stemp);
mkstemp(ttemp);
mkstemp(ptemp); mkstemp(ptemp);
FILE* f = fopen(stemp, "wb"); int r = bsdiff(src->data, src->len, &(src->I), tgt->data, tgt->len, ptemp);
if (f == NULL) { if (r != 0) {
fprintf(stderr, "failed to open src chunk %s: %s\n", fprintf(stderr, "bsdiff() failed: %d\n", r);
stemp, strerror(errno));
return NULL;
}
if (fwrite(src->data, 1, src->len, f) != src->len) {
fprintf(stderr, "failed to write src chunk to %s: %s\n",
stemp, strerror(errno));
return NULL;
}
fclose(f);
f = fopen(ttemp, "wb");
if (f == NULL) {
fprintf(stderr, "failed to open tgt chunk %s: %s\n",
ttemp, strerror(errno));
return NULL;
}
if (fwrite(tgt->data, 1, tgt->len, f) != tgt->len) {
fprintf(stderr, "failed to write tgt chunk to %s: %s\n",
ttemp, strerror(errno));
return NULL;
}
fclose(f);
char cmd[200];
sprintf(cmd, "bsdiff %s %s %s", stemp, ttemp, ptemp);
if (system(cmd) != 0) {
fprintf(stderr, "failed to run bsdiff: %s\n", strerror(errno));
return NULL; return NULL;
} }
@ -641,8 +623,6 @@ unsigned char* MakePatch(ImageChunk* src, ImageChunk* tgt, size_t* size) {
unsigned char* data = malloc(st.st_size); unsigned char* data = malloc(st.st_size);
if (tgt->type == CHUNK_NORMAL && tgt->len <= st.st_size) { if (tgt->type == CHUNK_NORMAL && tgt->len <= st.st_size) {
unlink(stemp);
unlink(ttemp);
unlink(ptemp); unlink(ptemp);
tgt->type = CHUNK_RAW; tgt->type = CHUNK_RAW;
@ -652,7 +632,7 @@ unsigned char* MakePatch(ImageChunk* src, ImageChunk* tgt, size_t* size) {
*size = st.st_size; *size = st.st_size;
f = fopen(ptemp, "rb"); FILE* f = fopen(ptemp, "rb");
if (f == NULL) { if (f == NULL) {
fprintf(stderr, "failed to open patch %s: %s\n", ptemp, strerror(errno)); fprintf(stderr, "failed to open patch %s: %s\n", ptemp, strerror(errno));
return NULL; return NULL;
@ -663,8 +643,6 @@ unsigned char* MakePatch(ImageChunk* src, ImageChunk* tgt, size_t* size) {
} }
fclose(f); fclose(f);
unlink(stemp);
unlink(ttemp);
unlink(ptemp); unlink(ptemp);
tgt->source_start = src->start; tgt->source_start = src->start;