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authorEelco Dolstra <e.dolstra@tudelft.nl>2004-12-29T22·08+0000
committerEelco Dolstra <e.dolstra@tudelft.nl>2004-12-29T22·08+0000
commit4f07ebc67e74629724c441352a58b12143383129 (patch)
tree52fad623c7192402e2d8960dc6c259dff66779b2 /src/bsdiff-4.2/bspatch.c
parent54d8f0858825e9ae4c8fdf54b7c2019edee05237 (diff)
* Integrated bsdiff/bspatch 4.2 (from
  http://www.daemonology.net/bsdiff/bsdiff-4.2.tar.gz) into the source
  tree.  The license is a bit peculiar, but it does allow verbatim
  copying, which is what we do here (i.e., so don't make any changes
  to the sources).

Diffstat (limited to 'src/bsdiff-4.2/bspatch.c')
-rw-r--r--src/bsdiff-4.2/bspatch.c216
1 files changed, 216 insertions, 0 deletions
diff --git a/src/bsdiff-4.2/bspatch.c b/src/bsdiff-4.2/bspatch.c
new file mode 100644
index 000000000000..1386a7096213
--- /dev/null
+++ b/src/bsdiff-4.2/bspatch.c
@@ -0,0 +1,216 @@
+/*
+  .c -- Binary patcher
+
+  Copyright 2003,2004 Colin Percival
+
+  For the terms under which this work may be distributed, please see
+  the adjoining file "LICENSE".
+*/
+
+#ifndef BZIP2
+#define BZIP2 "/usr/bin/bzip2"
+#endif
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <err.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/wait.h>
+
+ssize_t loopread(int d,void *buf,size_t nbytes)
+{
+	ssize_t ptr,lenread;
+
+	for(ptr=0;ptr<nbytes;ptr+=lenread) {
+		lenread=read(d,buf+ptr,nbytes-ptr);
+		if(lenread==0) return ptr;
+		if(lenread==-1) return -1;
+	};
+	return ptr;
+}
+
+int bz2read(int fd,off_t offset,off_t len,char * fname,pid_t * pids)
+{
+	int p0[2],p1[2];
+	u_char * data;
+
+	if((pipe(p0)==-1) || (pipe(p1)==-1)) err(1,NULL);
+
+	if((pids[0]=fork())==-1) err(1,NULL);
+	if(pids[0]==0) {
+		if(close(0) || close(1) || close(p0[0]) ||
+			close(p1[0]) || close(p1[1])) err(1,NULL);
+		if((data=malloc(len+1))==NULL) err(1,NULL);
+		if((pread(fd,data,len,offset)!=len) || close(fd))
+			err(1,"%s",fname);
+		if((write(p0[1],data,len)!=len) || close(p0[1]))
+			err(1,NULL);
+		free(data);
+		_exit(0);
+	};
+
+	if((pids[1]=fork())==-1) err(1,NULL);
+	if(pids[1]==0) {
+		if(close(0) || close(1) || close(p0[1]) ||
+			close(p1[0])) err(1,NULL);
+		if((dup2(p0[0],0)==-1) || close(p0[0])) err(1,NULL);
+		if((dup2(p1[1],1)==-1) || close(p1[1])) err(1,NULL);
+		if(close(fd)==-1) err(1,"%s",fname);
+
+		execl(BZIP2,BZIP2,"-dc",NULL);
+		err(1,"%s",BZIP2);
+	};
+
+	if(close(p0[0]) || close(p0[1]) || close(p1[1])) err(1,NULL);
+
+	return p1[0];
+}
+
+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 main(int argc,char * argv[])
+{
+	int fd,ctrlpipe,diffpipe,extrapipe;
+	pid_t pids[6];
+	ssize_t patchsize,oldsize,newsize;
+	ssize_t bzctrllen,bzdatalen;
+	u_char header[32],buf[8];
+	int version=0;
+	u_char *old, *new;
+	off_t oldpos,newpos;
+	off_t ctrl[3];
+	off_t lenread;
+	off_t i;
+
+	if(argc!=4) errx(1,"usage: %s oldfile newfile patchfile\n",argv[0]);
+
+	if(((fd=open(argv[3],O_RDONLY,0))<0) ||
+		((patchsize=lseek(fd,0,SEEK_END))==-1) ||
+		(lseek(fd,0,SEEK_SET)!=0)) err(1,"%s",argv[3]);
+	if(patchsize<32) errx(1,"Corrupt patch\n");
+
+	/*
+	  Ok, this is going to be messy.  There are two different patch
+	formats which we need to support.
+
+	  The old format (pre-4.0) is:
+		0	8	"QSUFDIFF" or "BSDIFF30"
+		8	8	X
+		16	8	Y
+		24	8	sizeof(newfile)
+		32	X	bzip2(control block)
+		32+X	Y	bzip2(data block)
+	with control block a set of pairs (x,y) meaning "seek forward
+	in oldfile by y bytes, and add the next x bytes to x bytes from
+	the data block".
+
+	  The new format (4.0) is:
+		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".
+	*/
+
+	if(read(fd,header,32)!=32) err(1,"%s",argv[3]);
+	if(memcmp(header,"QSUFDIFF",8)==0) version=1;
+	if(memcmp(header,"BSDIFF30",8)==0) version=1;
+	if(memcmp(header,"BSDIFF40",8)==0) version=2;
+
+	if(!version) errx(1,"Corrupt patch\n");
+
+	bzctrllen=offtin(header+8);
+	bzdatalen=offtin(header+16);
+	newsize=offtin(header+24);
+	if((bzctrllen<0) || (bzdatalen<0) || (newsize<0) ||
+		((version==1) && (32+bzctrllen+bzdatalen!=patchsize)))
+		errx(1,"Corrupt patch\n");
+
+	ctrlpipe=bz2read(fd,32,bzctrllen,argv[3],pids);
+	diffpipe=bz2read(fd,32+bzctrllen,bzdatalen,argv[3],pids+2);
+	if(version==2) {
+		extrapipe=bz2read(fd,32+bzctrllen+bzdatalen,
+			patchsize-(32+bzctrllen+bzdatalen),argv[3],pids+4);
+	};
+
+	if(close(fd)==-1) err(1,"%s",argv[3]);
+	if(((fd=open(argv[1],O_RDONLY,0))<0) ||
+		((oldsize=lseek(fd,0,SEEK_END))==-1) ||
+		((old=malloc(oldsize+1))==NULL) ||
+		(lseek(fd,0,SEEK_SET)!=0) ||
+		(read(fd,old,oldsize)!=oldsize) ||
+		(close(fd)==-1)) err(1,"%s",argv[1]);
+	if((new=malloc(newsize+1))==NULL) err(1,NULL);
+
+	oldpos=0;newpos=0;
+	while(newpos<newsize) {
+		for(i=0;i<=version;i++) {
+			if((lenread=loopread(ctrlpipe,buf,8))<0) err(1,NULL);
+			if(lenread<8) errx(1,"Corrupt patch\n");
+			ctrl[i]=offtin(buf);
+		};
+
+		if(version==1) oldpos+=ctrl[1];
+
+		if(newpos+ctrl[0]>newsize) errx(1,"Corrupt patch\n");
+		if((lenread=loopread(diffpipe,new+newpos,ctrl[0]))<0)
+			err(1,NULL);
+		if(lenread!=ctrl[0]) errx(1,"Corrupt patch\n");
+		for(i=0;i<ctrl[0];i++)
+			if((oldpos+i>=0) && (oldpos+i<oldsize))
+				new[newpos+i]+=old[oldpos+i];
+		newpos+=ctrl[0];
+		oldpos+=ctrl[0];
+
+		if(version==2) {
+			if(newpos+ctrl[1]>newsize) errx(1,"Corrupt patch\n");
+			if((lenread=loopread(extrapipe,new+newpos,ctrl[1]))<0)
+				err(1,NULL);
+			if(lenread!=ctrl[1]) errx(1,"Corrupt patch\n");
+
+			newpos+=ctrl[1];
+			oldpos+=ctrl[2];
+		};
+	};
+
+	if(loopread(ctrlpipe,buf,1)!=0) errx(1,"Corrupt patch\n");
+	if(loopread(diffpipe,buf,1)!=0) errx(1,"Corrupt patch\n");
+	if(version==2)
+		if(loopread(extrapipe,buf,1)!=0) errx(1,"Corrupt patch\n");
+
+	if(close(ctrlpipe) || close(diffpipe) || 
+		((version==2) && close(extrapipe)))
+		err(1,NULL);
+	for(i=0;i<(version+1)*2;i++) waitpid(pids[i],NULL,0);
+
+	if(((fd=open(argv[2],O_CREAT|O_TRUNC|O_WRONLY,0666))<0) ||
+		(write(fd,new,newsize)!=newsize) || (close(fd)==-1))
+		err(1,"%s",argv[2]);
+
+	free(new);
+	free(old);
+
+	return 0;
+}