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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/bsdiff.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/bsdiff.c')
-rw-r--r--src/bsdiff-4.2/bsdiff.c385
1 files changed, 385 insertions, 0 deletions
diff --git a/src/bsdiff-4.2/bsdiff.c b/src/bsdiff-4.2/bsdiff.c
new file mode 100644
index 000000000000..f47226c1e0a6
--- /dev/null
+++ b/src/bsdiff-4.2/bsdiff.c
@@ -0,0 +1,385 @@
+/*
+  bsdiff.c -- Binary patch generator.
+
+  Copyright 2003 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 <string.h>
+#include <err.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/wait.h>
+
+#define MIN(x,y) (((x)<(y)) ? (x) : (y))
+
+void split(off_t *I,off_t *V,off_t start,off_t len,off_t h)
+{
+	off_t i,j,k,x,tmp,jj,kk;
+
+	if(len<16) {
+		for(k=start;k<start+len;k+=j) {
+			j=1;x=V[I[k]+h];
+			for(i=1;k+i<start+len;i++) {
+				if(V[I[k+i]+h]<x) {
+					x=V[I[k+i]+h];
+					j=0;
+				};
+				if(V[I[k+i]+h]==x) {
+					tmp=I[k+j];I[k+j]=I[k+i];I[k+i]=tmp;
+					j++;
+				};
+			};
+			for(i=0;i<j;i++) V[I[k+i]]=k+j-1;
+			if(j==1) I[k]=-1;
+		};
+		return;
+	};
+
+	x=V[I[start+len/2]+h];
+	jj=0;kk=0;
+	for(i=start;i<start+len;i++) {
+		if(V[I[i]+h]<x) jj++;
+		if(V[I[i]+h]==x) kk++;
+	};
+	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);
+}
+
+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;
+}
+
+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;
+}
+
+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);
+	};
+}
+
+void offtout(off_t x,u_char *buf)
+{
+	off_t y;
+
+	if(x<0) y=-x; else y=x;
+
+		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;
+
+	if(x<0) buf[7]|=0x80;
+}
+
+int main(int argc,char *argv[])
+{
+	int fd,p[2];
+	pid_t pid;
+	u_char *old,*new;
+	off_t oldsize,newsize;
+	off_t *I,*V;
+
+	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];
+
+	if(argc!=4) errx(1,"usage: %s oldfile newfile patchfile\n",argv[0]);
+
+	/* Allocate oldsize+1 bytes instead of oldsize bytes to ensure
+		that we never try to malloc(0) and get a NULL pointer */
+	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(((I=malloc((oldsize+1)*sizeof(off_t)))==NULL) ||
+		((V=malloc((oldsize+1)*sizeof(off_t)))==NULL)) err(1,NULL);
+
+	qsufsort(I,V,old,oldsize);
+
+	free(V);
+
+	/* Allocate newsize+1 bytes instead of newsize bytes to ensure
+		that we never try to malloc(0) and get a NULL pointer */
+	if(((fd=open(argv[2],O_RDONLY,0))<0) ||
+		((newsize=lseek(fd,0,SEEK_END))==-1) ||
+		((new=malloc(newsize+1))==NULL) ||
+		(lseek(fd,0,SEEK_SET)!=0) ||
+		(read(fd,new,newsize)!=newsize) ||
+		(close(fd)==-1)) err(1,"%s",argv[2]);
+
+	if(((db=malloc(newsize+1))==NULL) ||
+		((eb=malloc(newsize+1))==NULL)) err(1,NULL);
+	dblen=0;
+	eblen=0;
+
+	if((fd=open(argv[3],O_CREAT|O_TRUNC|O_WRONLY,0666))<0)
+		err(1,"%s",argv[3]);
+
+	/* Header is
+		0	8	 "BSDIFF40"
+		8	8	length of bzip2ed ctrl block
+		16	8	length of bzip2ed diff block
+		24	8	length of new file */
+	/* File is
+		0	32	Header
+		32	??	Bzip2ed ctrl block
+		??	??	Bzip2ed diff block
+		??	??	Bzip2ed extra block */
+	memcpy(header,"BSDIFF40",8);
+	memset(header+8,0,24);
+	if(write(fd,header,32)!=32) err(1,"%s",argv[3]);
+
+	if((pipe(p)==-1) || ((pid=fork())==-1)) err(1,NULL);
+	if(pid==0) {
+		if((close(0)==-1) || (close(1)==-1) || (dup2(fd,1)==-1) ||
+			(dup2(p[0],0)==-1) || (close(fd)==-1) ||
+			(close(p[0])==-1) || (close(p[1])==-1))
+			err(1,NULL);
+		execl(BZIP2,BZIP2,"-zc",NULL);
+		err(1,"%s",BZIP2);
+	};
+	if(close(p[0])==-1) err(1,NULL);
+
+	scan=0;len=0;
+	lastscan=0;lastpos=0;lastoffset=0;
+	while(scan<newsize) {
+		oldscore=0;
+
+		for(scsc=scan+=len;scan<newsize;scan++) {
+			len=search(I,old,oldsize,new+scan,newsize-scan,
+					0,oldsize,&pos);
+
+			for(;scsc<scan+len;scsc++)
+			if((scsc+lastoffset<oldsize) &&
+				(old[scsc+lastoffset] == new[scsc]))
+				oldscore++;
+
+			if(((len==oldscore) && (len!=0)) || 
+				(len>oldscore+8)) break;
+
+			if((scan+lastoffset<oldsize) &&
+				(old[scan+lastoffset] == new[scan]))
+				oldscore--;
+		};
+
+		if((len!=oldscore) || (scan==newsize)) {
+			s=0;Sf=0;lenf=0;
+			for(i=0;(lastscan+i<scan)&&(lastpos+i<oldsize);) {
+				if(old[lastpos+i]==new[lastscan+i]) s++;
+				i++;
+				if(s*2-i>Sf*2-lenf) { Sf=s; lenf=i; };
+			};
+
+			lenb=0;
+			if(scan<newsize) {
+				s=0;Sb=0;
+				for(i=1;(scan>=lastscan+i)&&(pos>=i);i++) {
+					if(old[pos-i]==new[scan-i]) s++;
+					if(s*2-i>Sb*2-lenb) { Sb=s; lenb=i; };
+				};
+			};
+
+			if(lastscan+lenf>scan-lenb) {
+				overlap=(lastscan+lenf)-(scan-lenb);
+				s=0;Ss=0;lens=0;
+				for(i=0;i<overlap;i++) {
+					if(new[lastscan+lenf-overlap+i]==
+					   old[lastpos+lenf-overlap+i]) s++;
+					if(new[scan-lenb+i]==
+					   old[pos-lenb+i]) s--;
+					if(s>Ss) { Ss=s; lens=i+1; };
+				};
+
+				lenf+=lens-overlap;
+				lenb-=lens;
+			};
+
+			for(i=0;i<lenf;i++)
+				db[dblen+i]=new[lastscan+i]-old[lastpos+i];
+			for(i=0;i<(scan-lenb)-(lastscan+lenf);i++)
+				eb[eblen+i]=new[lastscan+lenf+i];
+
+			dblen+=lenf;
+			eblen+=(scan-lenb)-(lastscan+lenf);
+
+			offtout(lenf,buf);
+			if(write(p[1],buf,8)!=8) err(1,NULL);
+			offtout((scan-lenb)-(lastscan+lenf),buf);
+			if(write(p[1],buf,8)!=8) err(1,NULL);
+			offtout((pos-lenb)-(lastpos+lenf),buf);
+			if(write(p[1],buf,8)!=8) err(1,NULL);
+
+			lastscan=scan-lenb;
+			lastpos=pos-lenb;
+			lastoffset=pos-scan;
+		};
+	};
+
+	if((close(p[1])==-1) || (waitpid(pid,NULL,0)!=pid)) err(1,NULL);
+
+	if((len=lseek(fd,0,SEEK_END))==-1) err(1,"%s",argv[3]);
+	offtout(len-32,buf);
+	if((lseek(fd,8,SEEK_SET)!=8) || (write(fd,buf,8)!=8))
+		err(1,"%s",argv[3]);
+	offtout(newsize,buf);
+	if((lseek(fd,24,SEEK_SET)!=24) || (write(fd,buf,8)!=8))
+		err(1,"%s",argv[3]);
+
+	if(lseek(fd,0,SEEK_END)==-1) err(1,"%s",argv[3]);
+	if((pipe(p)==-1) || ((pid=fork())==-1)) err(1,NULL);
+	if(pid==0) {
+		if((close(0)==-1) || (close(1)==-1) || (dup2(fd,1)==-1) ||
+			(dup2(p[0],0)==-1) || (close(fd)==-1) ||
+			(close(p[0])==-1) || (close(p[1])==-1))
+			err(1,NULL);
+		execl(BZIP2,BZIP2,"-zc",NULL);
+		err(1,"%s",BZIP2);
+	};
+	if(close(p[0])==-1) err(1,NULL);
+	if(write(p[1],db,dblen)!=dblen) err(1,NULL);
+	if((close(p[1])==-1) || (waitpid(pid,NULL,0)!=pid)) err(1,NULL);
+
+	if((newsize=lseek(fd,0,SEEK_END))==-1) err(1,"%s",argv[3]);
+	offtout(newsize-len,buf);
+	if((lseek(fd,16,SEEK_SET)!=16) || (write(fd,buf,8)!=8))
+		err(1,"%s",argv[3]);
+
+	if(lseek(fd,0,SEEK_END)==-1) err(1,"%s",argv[3]);
+	if((pipe(p)==-1) || ((pid=fork())==-1)) err(1,NULL);
+	if(pid==0) {
+		if((close(0)==-1) || (close(1)==-1) || (dup2(fd,1)==-1) ||
+			(dup2(p[0],0)==-1) || (close(fd)==-1) ||
+			(close(p[0])==-1) || (close(p[1])==-1))
+			err(1,NULL);
+		execl(BZIP2,BZIP2,"-zc",NULL);
+		err(1,"%s",BZIP2);
+	};
+	if(close(p[0])==-1) err(1,NULL);
+	if(write(p[1],eb,eblen)!=eblen) err(1,NULL);
+	if((close(p[1])==-1) || (waitpid(pid,NULL,0)!=pid)) err(1,NULL);
+	if(close(fd)==-1) err(1,"%s",argv[3]);
+
+	free(db);
+	free(eb);
+	free(I);
+	free(old);
+	free(new);
+
+	return 0;
+}