diff --git a/Android.mk b/Android.mk
new file mode 100644
index 0000000..7cef9b8
--- /dev/null
+++ b/Android.mk
@@ -0,0 +1,36 @@
+# 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.
+
+ifneq ($(TARGET_SIMULATOR),true)
+
+LOCAL_PATH := $(call my-dir)
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := bsdiff.c
+LOCAL_MODULE := bsdiff
+LOCAL_MODULE_TAGS := eng
+LOCAL_C_INCLUDES += external/bzip2
+LOCAL_STATIC_LIBRARIES := libbz
+include $(BUILD_HOST_EXECUTABLE)
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := bspatch.c
+LOCAL_MODULE := bspatch
+LOCAL_MODULE_TAGS := eng
+LOCAL_C_INCLUDES += external/bzip2
+LOCAL_STATIC_LIBRARIES := libbz
+include $(BUILD_HOST_EXECUTABLE)
+
+endif  # !TARGET_SIMULATOR
diff --git a/MODULE_LICENSE_BSD_LIKE b/MODULE_LICENSE_BSD_LIKE
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/MODULE_LICENSE_BSD_LIKE
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..a522607
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,15 @@
+CFLAGS		+=	-O3 -lbz2
+
+PREFIX		?=	/usr/local
+INSTALL_PROGRAM	?=	${INSTALL} -c -s -m 555
+INSTALL_MAN	?=	${INSTALL} -c -m 444
+
+all:		bsdiff bspatch
+bsdiff:		bsdiff.c
+bspatch:	bspatch.c
+
+install:
+	${INSTALL_PROGRAM} bsdiff bspatch ${PREFIX}/bin
+.ifndef WITHOUT_MAN
+	${INSTALL_MAN} bsdiff.1 bspatch.1 ${PREFIX}/man/man1
+.endif
diff --git a/README.android b/README.android
new file mode 100644
index 0000000..9458d41
--- /dev/null
+++ b/README.android
@@ -0,0 +1,6 @@
+This is bsdiff-4.3 from http://www.daemonology.net/bsdiff/.
+
+This file, the Android.mk makefile, and the empty
+MODULE_LICENSE_BSD_LIKE file were added.
+
+Changes in the source are marked with "// android" comments.
diff --git a/bsdiff.1 b/bsdiff.1
new file mode 100644
index 0000000..ead6c4d
--- /dev/null
+++ b/bsdiff.1
@@ -0,0 +1,63 @@
+.\"-
+.\" Copyright 2003-2005 Colin Percival
+.\" All rights reserved
+.\"
+.\" 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.
+.\"
+.\" $FreeBSD: src/usr.bin/bsdiff/bsdiff/bsdiff.1,v 1.1 2005/08/06 01:59:05 cperciva Exp $
+.\"
+.Dd May 18, 2003
+.Dt BSDIFF 1
+.Os FreeBSD
+.Sh NAME
+.Nm bsdiff
+.Nd generate a patch between two binary files
+.Sh SYNOPSIS
+.Nm
+.Ao Ar oldfile Ac Ao Ar newfile Ac Ao Ar patchfile Ac
+.Sh DESCRIPTION
+.Nm
+compares
+.Ao Ar oldfile Ac
+to
+.Ao Ar newfile Ac
+and writes to
+.Ao Ar patchfile Ac
+a binary patch suitable for use by bspatch(1).
+When
+.Ao Ar oldfile Ac
+and
+.Ao Ar newfile Ac
+are two versions of an executable program, the
+patches produced are on average a factor of five smaller
+than those produced by any other binary patch tool known
+to the author.
+.Pp
+.Nm
+uses memory equal to 17 times the size of 
+.Ao Ar oldfile Ac ,
+and requires
+an absolute minimum working set size of 8 times the size of oldfile.
+.Sh SEE ALSO
+.Xr bspatch 1
+.Sh AUTHORS
+.An Colin Percival Aq cperciva@freebsd.org
diff --git a/bsdiff.c b/bsdiff.c
new file mode 100644
index 0000000..150a7f7
--- /dev/null
+++ b/bsdiff.c
@@ -0,0 +1,404 @@
+/*-
+ * Copyright 2003-2005 Colin Percival
+ * All rights reserved
+ *
+ * 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.
+ */
+
+#if 0
+__FBSDID("$FreeBSD: src/usr.bin/bsdiff/bsdiff/bsdiff.c,v 1.1 2005/08/06 01:59:05 cperciva Exp $");
+#endif
+
+#include <sys/types.h>
+
+#include <bzlib.h>
+#include <err.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#define MIN(x,y) (((x)<(y)) ? (x) : (y))
+
+static 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);
+}
+
+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;
+
+	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;
+	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];
+	FILE * pf;
+	BZFILE * pfbz2;
+	int bz2err;
+
+	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;
+
+	/* Create the patch file */
+	if ((pf = fopen(argv[3], "w")) == NULL)
+		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);
+	offtout(0, header + 8);
+	offtout(0, header + 16);
+	offtout(newsize, header + 24);
+	if (fwrite(header, 32, 1, pf) != 1)
+		err(1, "fwrite(%s)", argv[3]);
+
+	/* Compute the differences, writing ctrl as we go */
+	if ((pfbz2 = BZ2_bzWriteOpen(&bz2err, pf, 9, 0, 0)) == NULL)
+		errx(1, "BZ2_bzWriteOpen, bz2err = %d", bz2err);
+	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);
+			BZ2_bzWrite(&bz2err, pfbz2, buf, 8);
+			if (bz2err != BZ_OK)
+				errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
+
+			offtout((scan-lenb)-(lastscan+lenf),buf);
+			BZ2_bzWrite(&bz2err, pfbz2, buf, 8);
+			if (bz2err != BZ_OK)
+				errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
+
+			offtout((pos-lenb)-(lastpos+lenf),buf);
+			BZ2_bzWrite(&bz2err, pfbz2, buf, 8);
+			if (bz2err != BZ_OK)
+				errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
+
+			lastscan=scan-lenb;
+			lastpos=pos-lenb;
+			lastoffset=pos-scan;
+		};
+	};
+	BZ2_bzWriteClose(&bz2err, pfbz2, 0, NULL, NULL);
+	if (bz2err != BZ_OK)
+		errx(1, "BZ2_bzWriteClose, bz2err = %d", bz2err);
+
+	/* Compute size of compressed ctrl data */
+	if ((len = ftello(pf)) == -1)
+		err(1, "ftello");
+	offtout(len-32, header + 8);
+
+	/* Write compressed diff data */
+	if ((pfbz2 = BZ2_bzWriteOpen(&bz2err, pf, 9, 0, 0)) == NULL)
+		errx(1, "BZ2_bzWriteOpen, bz2err = %d", bz2err);
+	BZ2_bzWrite(&bz2err, pfbz2, db, dblen);
+	if (bz2err != BZ_OK)
+		errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
+	BZ2_bzWriteClose(&bz2err, pfbz2, 0, NULL, NULL);
+	if (bz2err != BZ_OK)
+		errx(1, "BZ2_bzWriteClose, bz2err = %d", bz2err);
+
+	/* Compute size of compressed diff data */
+	if ((newsize = ftello(pf)) == -1)
+		err(1, "ftello");
+	offtout(newsize - len, header + 16);
+
+	/* Write compressed extra data */
+	if ((pfbz2 = BZ2_bzWriteOpen(&bz2err, pf, 9, 0, 0)) == NULL)
+		errx(1, "BZ2_bzWriteOpen, bz2err = %d", bz2err);
+	BZ2_bzWrite(&bz2err, pfbz2, eb, eblen);
+	if (bz2err != BZ_OK)
+		errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
+	BZ2_bzWriteClose(&bz2err, pfbz2, 0, NULL, NULL);
+	if (bz2err != BZ_OK)
+		errx(1, "BZ2_bzWriteClose, bz2err = %d", bz2err);
+
+	/* Seek to the beginning, write the header, and close the file */
+	if (fseeko(pf, 0, SEEK_SET))
+		err(1, "fseeko");
+	if (fwrite(header, 32, 1, pf) != 1)
+		err(1, "fwrite(%s)", argv[3]);
+	if (fclose(pf))
+		err(1, "fclose");
+
+	/* Free the memory we used */
+	free(db);
+	free(eb);
+	free(I);
+	free(old);
+	free(new);
+
+	return 0;
+}
diff --git a/bspatch.1 b/bspatch.1
new file mode 100644
index 0000000..82a2781
--- /dev/null
+++ b/bspatch.1
@@ -0,0 +1,59 @@
+.\"-
+.\" Copyright 2003-2005 Colin Percival
+.\" All rights reserved
+.\"
+.\" 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.
+.\"
+.\" $FreeBSD: src/usr.bin/bsdiff/bspatch/bspatch.1,v 1.1 2005/08/06 01:59:06 cperciva Exp $
+.\"
+.Dd May 18, 2003
+.Dt BSPATCH 1
+.Os FreeBSD
+.Sh NAME
+.Nm bspatch
+.Nd apply a patch built with bsdiff(1)
+.Sh SYNOPSIS
+.Nm
+.Ao Ar oldfile Ac Ao Ar newfile Ac Ao Ar patchfile Ac
+.Sh DESCRIPTION
+.Nm
+generates
+.Ao Ar newfile Ac
+from
+.Ao Ar oldfile Ac
+and
+.Ao Ar patchfile Ac
+where
+.Ao Ar patchfile Ac
+is a binary patch built by bsdiff(1).
+.Pp
+.Nm
+uses memory equal to the size of 
+.Ao Ar oldfile Ac
+plus the size of 
+.Ao Ar newfile Ac ,
+but can tolerate a very small working set without a dramatic loss
+of performance.
+.Sh SEE ALSO
+.Xr bsdiff 1
+.Sh AUTHORS
+.An Colin Percival Aq cperciva@freebsd.org
diff --git a/bspatch.c b/bspatch.c
new file mode 100644
index 0000000..3ef698f
--- /dev/null
+++ b/bspatch.c
@@ -0,0 +1,205 @@
+/*-
+ * Copyright 2003-2005 Colin Percival
+ * All rights reserved
+ *
+ * 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.
+ */
+
+#if 0
+__FBSDID("$FreeBSD: src/usr.bin/bsdiff/bspatch/bspatch.c,v 1.1 2005/08/06 01:59:06 cperciva Exp $");
+#endif
+
+#include <bzlib.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <err.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/types.h>    // android
+
+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 main(int argc,char * argv[])
+{
+	FILE * f, * cpf, * dpf, * epf;
+	BZFILE * cpfbz2, * dpfbz2, * epfbz2;
+	int cbz2err, dbz2err, ebz2err;
+	int fd;
+	ssize_t oldsize,newsize;
+	ssize_t bzctrllen,bzdatalen;
+	u_char header[32],buf[8];
+	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]);
+
+	/* Open patch file */
+	if ((f = fopen(argv[3], "r")) == NULL)
+		err(1, "fopen(%s)", argv[3]);
+
+	/*
+	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".
+	*/
+
+	/* Read header */
+	if (fread(header, 1, 32, f) < 32) {
+		if (feof(f))
+			errx(1, "Corrupt patch\n");
+		err(1, "fread(%s)", argv[3]);
+	}
+
+	/* Check for appropriate magic */
+	if (memcmp(header, "BSDIFF40", 8) != 0)
+		errx(1, "Corrupt patch\n");
+
+	/* Read lengths from header */
+	bzctrllen=offtin(header+8);
+	bzdatalen=offtin(header+16);
+	newsize=offtin(header+24);
+	if((bzctrllen<0) || (bzdatalen<0) || (newsize<0))
+		errx(1,"Corrupt patch\n");
+
+	/* Close patch file and re-open it via libbzip2 at the right places */
+	if (fclose(f))
+		err(1, "fclose(%s)", argv[3]);
+	if ((cpf = fopen(argv[3], "r")) == NULL)
+		err(1, "fopen(%s)", argv[3]);
+	if (fseeko(cpf, 32, SEEK_SET))
+		err(1, "fseeko(%s, %lld)", argv[3],
+		    (long long)32);
+	if ((cpfbz2 = BZ2_bzReadOpen(&cbz2err, cpf, 0, 0, NULL, 0)) == NULL)
+		errx(1, "BZ2_bzReadOpen, bz2err = %d", cbz2err);
+	if ((dpf = fopen(argv[3], "r")) == NULL)
+		err(1, "fopen(%s)", argv[3]);
+	if (fseeko(dpf, 32 + bzctrllen, SEEK_SET))
+		err(1, "fseeko(%s, %lld)", argv[3],
+		    (long long)(32 + bzctrllen));
+	if ((dpfbz2 = BZ2_bzReadOpen(&dbz2err, dpf, 0, 0, NULL, 0)) == NULL)
+		errx(1, "BZ2_bzReadOpen, bz2err = %d", dbz2err);
+	if ((epf = fopen(argv[3], "r")) == NULL)
+		err(1, "fopen(%s)", argv[3]);
+	if (fseeko(epf, 32 + bzctrllen + bzdatalen, SEEK_SET))
+		err(1, "fseeko(%s, %lld)", argv[3],
+		    (long long)(32 + bzctrllen + bzdatalen));
+	if ((epfbz2 = BZ2_bzReadOpen(&ebz2err, epf, 0, 0, NULL, 0)) == NULL)
+		errx(1, "BZ2_bzReadOpen, bz2err = %d", ebz2err);
+
+	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) {
+		/* Read control data */
+		for(i=0;i<=2;i++) {
+			lenread = BZ2_bzRead(&cbz2err, cpfbz2, buf, 8);
+			if ((lenread < 8) || ((cbz2err != BZ_OK) &&
+			    (cbz2err != BZ_STREAM_END)))
+				errx(1, "Corrupt patch\n");
+			ctrl[i]=offtin(buf);
+		};
+
+		/* Sanity-check */
+		if(newpos+ctrl[0]>newsize)
+			errx(1,"Corrupt patch\n");
+
+		/* Read diff string */
+		lenread = BZ2_bzRead(&dbz2err, dpfbz2, new + newpos, ctrl[0]);
+		if ((lenread < ctrl[0]) ||
+		    ((dbz2err != BZ_OK) && (dbz2err != BZ_STREAM_END)))
+			errx(1, "Corrupt patch\n");
+
+		/* Add old data to diff string */
+		for(i=0;i<ctrl[0];i++)
+			if((oldpos+i>=0) && (oldpos+i<oldsize))
+				new[newpos+i]+=old[oldpos+i];
+
+		/* Adjust pointers */
+		newpos+=ctrl[0];
+		oldpos+=ctrl[0];
+
+		/* Sanity-check */
+		if(newpos+ctrl[1]>newsize)
+			errx(1,"Corrupt patch\n");
+
+		/* Read extra string */
+		lenread = BZ2_bzRead(&ebz2err, epfbz2, new + newpos, ctrl[1]);
+		if ((lenread < ctrl[1]) ||
+		    ((ebz2err != BZ_OK) && (ebz2err != BZ_STREAM_END)))
+			errx(1, "Corrupt patch\n");
+
+		/* Adjust pointers */
+		newpos+=ctrl[1];
+		oldpos+=ctrl[2];
+	};
+
+	/* Clean up the bzip2 reads */
+	BZ2_bzReadClose(&cbz2err, cpfbz2);
+	BZ2_bzReadClose(&dbz2err, dpfbz2);
+	BZ2_bzReadClose(&ebz2err, epfbz2);
+	if (fclose(cpf) || fclose(dpf) || fclose(epf))
+		err(1, "fclose(%s)", argv[3]);
+
+	/* Write the new file */
+	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;
+}