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-rw-r--r--onlineupdate/source/mbsdiff/bsdiff.cxx405
1 files changed, 405 insertions, 0 deletions
diff --git a/onlineupdate/source/mbsdiff/bsdiff.cxx b/onlineupdate/source/mbsdiff/bsdiff.cxx
new file mode 100644
index 000000000..72bbcde18
--- /dev/null
+++ b/onlineupdate/source/mbsdiff/bsdiff.cxx
@@ -0,0 +1,405 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ 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".
+
+ ChangeLog:
+ 2005-05-05 - Use the modified header struct from bspatch.h; use 32-bit
+ values throughout.
+ --Benjamin Smedberg <benjamin@smedbergs.us>
+ 2005-05-18 - Use the same CRC algorithm as bzip2, and leverage the CRC table
+ provided by libbz2.
+ --Darin Fisher <darin@meer.net>
+*/
+
+#include "bspatch.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#ifdef _WIN32
+#include <io.h>
+#include <winsock2.h>
+#else
+#include <unistd.h>
+#include <arpa/inet.h>
+#define _O_BINARY 0
+#endif
+
+#undef MIN
+#define MIN(x,y) (((x)<(y)) ? (x) : (y))
+
+/*---------------------------------------------------------------------------*/
+
+/* This variable lives in libbz2. It's declared in bzlib_private.h, so we just
+ * declare it here to avoid including that entire header file.
+ */
+extern "C" unsigned int BZ2_crc32Table[256];
+
+static unsigned int
+crc32(const unsigned char *buf, unsigned int len)
+{
+ unsigned int crc = 0xffffffffL;
+
+ const unsigned char *end = buf + len;
+ for (; buf != end; ++buf)
+ crc = (crc << 8) ^ BZ2_crc32Table[(crc >> 24) ^ *buf];
+
+ crc = ~crc;
+ return crc;
+}
+
+/*---------------------------------------------------------------------------*/
+
+static void
+reporterr(int e, const char *fmt, ...)
+{
+ if (fmt) {
+ va_list args;
+ va_start(args, fmt);
+ vfprintf(stderr, fmt, args);
+ va_end(args);
+ }
+
+ exit(e);
+}
+
+static void
+split(int32_t *I,int32_t *V,int32_t start,int32_t len,int32_t h)
+{
+ int32_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(int32_t *I,int32_t *V,unsigned char *old,int32_t oldsize)
+{
+ int32_t buckets[256];
+ int32_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 int32_t
+matchlen(unsigned char *old,int32_t oldsize,unsigned char *newbuf,int32_t newsize)
+{
+ int32_t i;
+
+ for(i=0;(i<oldsize)&&(i<newsize);i++)
+ if(old[i]!=newbuf[i]) break;
+
+ return i;
+}
+
+static int32_t
+search(int32_t *I,unsigned char *old,int32_t oldsize,
+ unsigned char *newbuf,int32_t newsize,int32_t st,int32_t en,int32_t *pos)
+{
+ int32_t x,y;
+
+ if(en-st<2) {
+ x=matchlen(old+I[st],oldsize-I[st],newbuf,newsize);
+ y=matchlen(old+I[en],oldsize-I[en],newbuf,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],newbuf,MIN(oldsize-I[x],newsize))<0) {
+ return search(I,old,oldsize,newbuf,newsize,x,en,pos);
+ } else {
+ return search(I,old,oldsize,newbuf,newsize,st,x,pos);
+ };
+}
+
+int main(int argc,char *argv[])
+{
+ int fd;
+ unsigned char *old = nullptr,*newbuf = nullptr;
+ int32_t oldsize = 0, newsize = 0;
+ int32_t *I = nullptr,*V = nullptr;
+
+ int32_t scan,pos = 0,len;
+ int32_t lastscan,lastpos,lastoffset;
+ int32_t oldscore,scsc;
+
+ int32_t s,Sf,lenf,Sb,lenb;
+ int32_t overlap,Ss,lens;
+ int32_t i;
+
+ int32_t dblen,eblen;
+ unsigned char *db,*eb = nullptr;
+
+ unsigned int scrc;
+
+ MBSPatchHeader header = {
+ {'M','B','D','I','F','F','1','0'},
+ 0, 0, 0, 0, 0, 0
+ };
+
+ uint32_t numtriples;
+
+ if(argc!=4)
+ reporterr(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|_O_BINARY,0))<0) ||
+ ((oldsize=lseek(fd,0,SEEK_END))==-1) ||
+ ((old=(unsigned char*) malloc(oldsize+1))==NULL) ||
+ (lseek(fd,0,SEEK_SET)!=0) ||
+ (read(fd,old,oldsize)!=oldsize) ||
+ (close(fd)==-1))
+ reporterr(1,"%s\n",argv[1]);
+
+ scrc = crc32(old, oldsize);
+
+ if(((I=(int32_t*) malloc((oldsize+1)*sizeof(int32_t)))==NULL) ||
+ ((V=(int32_t*) malloc((oldsize+1)*sizeof(int32_t)))==NULL))
+ reporterr(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|_O_BINARY,0))<0) ||
+ ((newsize=lseek(fd,0,SEEK_END))==-1) ||
+ ((newbuf=(unsigned char*) malloc(newsize+1))==NULL) ||
+ (lseek(fd,0,SEEK_SET)!=0) ||
+ (read(fd,newbuf,newsize)!=newsize) ||
+ (close(fd)==-1)) reporterr(1,"%s\n",argv[2]);
+
+ if(((db=(unsigned char*) malloc(newsize+1))==NULL) ||
+ ((eb=(unsigned char*) malloc(newsize+1))==NULL))
+ reporterr(1,NULL);
+
+ dblen=0;
+ eblen=0;
+
+ if((fd=open(argv[3],O_CREAT|O_TRUNC|O_WRONLY|_O_BINARY,0666))<0)
+ reporterr(1,"%s\n",argv[3]);
+
+ /* start writing here */
+
+ /* We don't know the lengths yet, so we will write the header again
+ at the end */
+
+ if(write(fd,&header,sizeof(MBSPatchHeader))!=sizeof(MBSPatchHeader))
+ reporterr(1,"%s\n",argv[3]);
+
+ scan=0;len=0;
+ lastscan=0;lastpos=0;lastoffset=0;
+ numtriples = 0;
+ while(scan<newsize) {
+ oldscore=0;
+
+ for(scsc=scan+=len;scan<newsize;scan++) {
+ len=search(I,old,oldsize,newbuf+scan,newsize-scan,
+ 0,oldsize,&pos);
+
+ for(;scsc<scan+len;scsc++)
+ if((scsc+lastoffset<oldsize) &&
+ (old[scsc+lastoffset] == newbuf[scsc]))
+ oldscore++;
+
+ if(((len==oldscore) && (len!=0)) ||
+ (len>oldscore+8)) break;
+
+ if((scan+lastoffset<oldsize) &&
+ (old[scan+lastoffset] == newbuf[scan]))
+ oldscore--;
+ };
+
+ if((len!=oldscore) || (scan==newsize)) {
+ MBSPatchTriple triple;
+
+ s=0;Sf=0;lenf=0;
+ for(i=0;(lastscan+i<scan)&&(lastpos+i<oldsize);) {
+ if(old[lastpos+i]==newbuf[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]==newbuf[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(newbuf[lastscan+lenf-overlap+i]==
+ old[lastpos+lenf-overlap+i]) s++;
+ if(newbuf[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]=newbuf[lastscan+i]-old[lastpos+i];
+ for(i=0;i<(scan-lenb)-(lastscan+lenf);i++)
+ eb[eblen+i]=newbuf[lastscan+lenf+i];
+
+ dblen+=lenf;
+ eblen+=(scan-lenb)-(lastscan+lenf);
+
+ triple.x = htonl(lenf);
+ triple.y = htonl((scan-lenb)-(lastscan+lenf));
+ triple.z = htonl((pos-lenb)-(lastpos+lenf));
+ if (write(fd,&triple,sizeof(triple)) != sizeof(triple))
+ reporterr(1,NULL);
+
+#ifdef DEBUG_bsmedberg
+ printf("Writing a block:\n"
+ " X: %u\n"
+ " Y: %u\n"
+ " Z: %i\n",
+ (uint32_t) lenf,
+ (uint32_t) ((scan-lenb)-(lastscan+lenf)),
+ (uint32_t) ((pos-lenb)-(lastpos+lenf)));
+#endif
+
+ ++numtriples;
+
+ lastscan=scan-lenb;
+ lastpos=pos-lenb;
+ lastoffset=pos-scan;
+ };
+ };
+
+ if(write(fd,db,dblen)!=dblen)
+ reporterr(1,NULL);
+
+ if(write(fd,eb,eblen)!=eblen)
+ reporterr(1,NULL);
+
+ header.slen = htonl(oldsize);
+ header.scrc32 = htonl(scrc);
+ header.dlen = htonl(newsize);
+ header.cblen = htonl(numtriples * sizeof(MBSPatchTriple));
+ header.difflen = htonl(dblen);
+ header.extralen = htonl(eblen);
+
+ if (lseek(fd,0,SEEK_SET) == -1 ||
+ write(fd,&header,sizeof(header)) != sizeof(header) ||
+ close(fd) == -1)
+ reporterr(1,NULL);
+
+ free(db);
+ free(eb);
+ free(I);
+ free(old);
+ free(newbuf);
+
+ return 0;
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 22:09:27 +0000