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Diffstat (limited to 'src/bsdiff-4.3/bsdiff.c')
| -rw-r--r-- | src/bsdiff-4.3/bsdiff.c | 405 |
1 files changed, 405 insertions, 0 deletions
diff --git a/src/bsdiff-4.3/bsdiff.c b/src/bsdiff-4.3/bsdiff.c new file mode 100644 index 000000000000..374ed038fa1f --- /dev/null +++ b/src/bsdiff-4.3/bsdiff.c @@ -0,0 +1,405 @@ +/*- + * 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); + if (len > 64 * 1024) break; + + 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; +} |