diff options
Diffstat (limited to '')
-rw-r--r-- | other-licenses/bsdiff/bsdiff.c | 411 |
1 files changed, 411 insertions, 0 deletions
diff --git a/other-licenses/bsdiff/bsdiff.c b/other-licenses/bsdiff/bsdiff.c new file mode 100644 index 0000000000..eaf9027365 --- /dev/null +++ b/other-licenses/bsdiff/bsdiff.c @@ -0,0 +1,411 @@ +/* vim:set ts=8 sw=8 sts=8 noet: */ +/* + 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 XP_WIN +#include <io.h> +#include <winsock2.h> +#define open _open +#define close _close +#define read _read +#define lseek _lseek +#define write _write +#else +#include <unistd.h> +#include <arpa/inet.h> +#define _O_BINARY 0 +#endif + +#include "crctable.h" + +#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 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,*newbuf; + int32_t oldsize,newsize; + int32_t *I,*V; + + int32_t scan,pos,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; + + 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+10)) 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*3-i*2>Sf*3-lenf*2) { 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*3-i*2>Sb*3-lenb*2) { 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; +} + |