432 lines
8.0 KiB
C
432 lines
8.0 KiB
C
#ifndef lint
|
|
static char sccsid[] = "@(#)diff3prog.c 1.1 94/10/31 SMI"; /* from S5R2 1.3 */
|
|
#endif
|
|
|
|
#include <stdio.h>
|
|
#
|
|
|
|
/* diff3 - 3-way differential file comparison*/
|
|
|
|
/* diff3 [-e] d13 d23 f1 f2 f3
|
|
*
|
|
* d13 = diff report on f1 vs f3
|
|
* d23 = diff report on f2 vs f3
|
|
* f1, f2, f3 the 3 files
|
|
*/
|
|
|
|
struct range {int from,to; };
|
|
/* from is first in range of changed lines
|
|
* to is last+1
|
|
* from=to=line after point of insertion
|
|
* for added lines
|
|
*/
|
|
struct diff {struct range old, new;};
|
|
|
|
#define NC 200
|
|
/* de is used to gather editing scripts,
|
|
* that are later spewed out in reverse order.
|
|
* its first element must be all zero
|
|
* the "new" component of de contains line positions
|
|
* or byte positions depending on when you look(!?)
|
|
*/
|
|
struct diff d13[NC];
|
|
struct diff d23[NC];
|
|
struct diff de[NC];
|
|
char line[256];
|
|
FILE *fp[3];
|
|
int linct[3] = {0,0,0};
|
|
/* the number of the last-read line in each file
|
|
* is kept in cline[0-2]
|
|
*/
|
|
int cline[3];
|
|
/* the latest known correspondence between line
|
|
* numbers of the 3 files is stored in last[1-3]
|
|
*/
|
|
int last[4];
|
|
int eflag;
|
|
int debug = 0;
|
|
|
|
main(argc,argv)
|
|
char **argv;
|
|
{
|
|
register i,m,n;
|
|
if(*argv[1]=='-') {
|
|
switch(argv[1][1]) {
|
|
default:
|
|
eflag = 3;
|
|
break;
|
|
case '3':
|
|
eflag = 2;
|
|
break;
|
|
case 'x':
|
|
eflag = 1;
|
|
}
|
|
argv++;
|
|
argc--;
|
|
}
|
|
if(argc<6) {
|
|
fprintf(stderr,"diff3: arg count\n");
|
|
exit(1);
|
|
}
|
|
m = readin(argv[1],d13);
|
|
n = readin(argv[2],d23);
|
|
for(i=0;i<=2;i++)
|
|
if((fp[i] = fopen(argv[i+3],"r")) == NULL) {
|
|
printf("diff3: can't open %s\n",argv[i+3]);
|
|
exit(1);
|
|
}
|
|
merge(m,n);
|
|
exit(0);
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
/*pick up the line numbers of allcahnges from
|
|
* one change file
|
|
* (this puts the numbers in a vector, which is not
|
|
* strictly necessary, since the vector is processed
|
|
* in one sequential pass. The vector could be optimized
|
|
* out of existence)
|
|
*/
|
|
|
|
readin(name,dd)
|
|
char *name;
|
|
struct diff *dd;
|
|
{
|
|
register i;
|
|
int a,b,c,d;
|
|
char kind;
|
|
char *p;
|
|
fp[0] = fopen(name,"r");
|
|
for(i=0;getchange(fp[0]);i++) {
|
|
if(i>=NC) {
|
|
fprintf(stderr,"diff3: too many changes\n");
|
|
exit(0);
|
|
}
|
|
p = line;
|
|
a = b = number(&p);
|
|
if(*p==',') {
|
|
p++;
|
|
b = number(&p);
|
|
}
|
|
kind = *p++;
|
|
c = d = number(&p);
|
|
if(*p==',') {
|
|
p++;
|
|
d = number(&p);
|
|
}
|
|
if(kind=='a')
|
|
a++;
|
|
if(kind=='d')
|
|
c++;
|
|
b++;
|
|
d++;
|
|
dd[i].old.from = a;
|
|
dd[i].old.to = b;
|
|
dd[i].new.from = c;
|
|
dd[i].new.to = d;
|
|
}
|
|
dd[i].old.from = dd[i-1].old.to;
|
|
dd[i].new.from = dd[i-1].new.to;
|
|
fclose(fp[0]);
|
|
return(i);
|
|
}
|
|
|
|
number(lc)
|
|
char **lc;
|
|
{
|
|
register nn;
|
|
nn = 0;
|
|
while(digit(**lc))
|
|
nn = nn*10 + *(*lc)++ - '0';
|
|
return(nn);
|
|
}
|
|
|
|
digit(c)
|
|
{
|
|
return(c>='0'&&c<='9');
|
|
}
|
|
|
|
getchange(b)
|
|
FILE *b;
|
|
{
|
|
while(getline(b))
|
|
if(digit(line[0]))
|
|
return(1);
|
|
return(0);
|
|
}
|
|
|
|
getline(b)
|
|
FILE *b;
|
|
{
|
|
register i, c;
|
|
for(i=0;i<sizeof(line)-1;i++) {
|
|
c = getc(b);
|
|
if(c==EOF)
|
|
break;
|
|
line[i] = c;
|
|
if(c=='\n') {
|
|
line[++i] = 0;
|
|
return(i);
|
|
}
|
|
}
|
|
return(0);
|
|
}
|
|
|
|
merge(m1,m2)
|
|
{
|
|
register struct diff *d1, *d2, *d3;
|
|
int dup;
|
|
int j;
|
|
int t1,t2;
|
|
d1 = d13;
|
|
d2 = d23;
|
|
j = 0;
|
|
for(;(t1 = d1<d13+m1) | (t2 = d2<d23+m2);) {
|
|
if(debug) {
|
|
printf("%d,%d=%d,%d %d,%d=%d,%d\n",
|
|
d1->old.from,d1->old.to,
|
|
d1->new.from,d1->new.to,
|
|
d2->old.from,d2->old.to,
|
|
d2->new.from,d2->new.to);
|
|
}
|
|
/* first file is different from others*/
|
|
if(!t2||t1&&d1->new.to < d2->new.from) {
|
|
/* stuff peculiar to 1st file */
|
|
if(eflag==0) {
|
|
separate("1");
|
|
change(1,&d1->old,0);
|
|
keep(2,&d1->old,&d1->new);
|
|
change(3,&d1->new,0);
|
|
}
|
|
d1++;
|
|
continue;
|
|
}
|
|
/* second file is different from others*/
|
|
if(!t1||t2&&d2->new.to < d1->new.from) {
|
|
if(eflag==0) {
|
|
separate("2");
|
|
keep(1,&d2->old,&d2->new);
|
|
change(2,&d2->old,0);
|
|
change(3,&d2->new,0);
|
|
}
|
|
d2++;
|
|
continue;
|
|
}
|
|
/* merge overlapping changes in first file
|
|
* this happens after extension see below*/
|
|
if(d1+1<d13+m1 &&
|
|
d1->new.to>=d1[1].new.from) {
|
|
d1[1].old.from = d1->old.from;
|
|
d1[1].new.from = d1->new.from;
|
|
d1++;
|
|
continue;
|
|
}
|
|
/* merge overlapping changes in second*/
|
|
if(d2+1<d23+m2 &&
|
|
d2->new.to>=d2[1].new.from) {
|
|
d2[1].old.from = d2->old.from;
|
|
d2[1].new.from = d2->new.from;
|
|
d2++;
|
|
continue;
|
|
}
|
|
/* stuff peculiar to third file or different in all*/
|
|
if(d1->new.from==d2->new.from&&
|
|
d1->new.to==d2->new.to) {
|
|
dup = duplicate(&d1->old,&d2->old);
|
|
/* dup=0 means all files differ
|
|
* dup =1 meands files 1&2 identical*/
|
|
if(eflag==0) {
|
|
separate(dup?"3":"");
|
|
change(1,&d1->old,dup);
|
|
change(2,&d2->old,0);
|
|
d3 = d1->old.to>d1->old.from?d1:d2;
|
|
change(3,&d3->new,0);
|
|
} else
|
|
j = edit(d1,dup,j);
|
|
d1++;
|
|
d2++;
|
|
continue;
|
|
}
|
|
/* overlapping changes from file1 & 2
|
|
* extend changes appropriately to
|
|
* make them coincide*/
|
|
if(d1->new.from<d2->new.from) {
|
|
d2->old.from -= d2->new.from-d1->new.from;
|
|
d2->new.from = d1->new.from;
|
|
}
|
|
else if(d2->new.from<d1->new.from) {
|
|
d1->old.from -= d1->new.from-d2->new.from;
|
|
d1->new.from = d2->new.from;
|
|
}
|
|
if(d1->new.to >d2->new.to) {
|
|
d2->old.to += d1->new.to - d2->new.to;
|
|
d2->new.to = d1->new.to;
|
|
}
|
|
else if(d2->new.to >d1->new.to) {
|
|
d1->old.to += d2->new.to - d1->new.to;
|
|
d1->new.to = d2->new.to;
|
|
}
|
|
}
|
|
if(eflag) {
|
|
edscript(j);
|
|
if(j)
|
|
printf("w\nq\n");
|
|
}
|
|
}
|
|
|
|
separate(s)
|
|
char *s;
|
|
{
|
|
printf("====%s\n",s);
|
|
}
|
|
|
|
/* the range of ines rold.from thru rold.to in file i
|
|
* is to be changed. it is to be printed only if
|
|
* it does not duplicate something to be printed later
|
|
*/
|
|
change(i,rold,dup)
|
|
struct range *rold;
|
|
{
|
|
printf("%d:",i);
|
|
last[i] = rold->to;
|
|
prange(rold);
|
|
if(dup)
|
|
return;
|
|
if(debug)
|
|
return;
|
|
i--;
|
|
skip(i,rold->from,(char *)0);
|
|
skip(i,rold->to," ");
|
|
}
|
|
|
|
/* print the range of line numbers, rold.from thru rold.to
|
|
* as n1,n2 or n1
|
|
*/
|
|
prange(rold)
|
|
struct range *rold;
|
|
{
|
|
if(rold->to<=rold->from)
|
|
printf("%da\n",rold->from-1);
|
|
else {
|
|
printf("%d",rold->from);
|
|
if(rold->to > rold->from+1)
|
|
printf(",%d",rold->to-1);
|
|
printf("c\n");
|
|
}
|
|
}
|
|
|
|
/* no difference was reported by diff between file 1(or 2)
|
|
* and file 3, and an artificial dummy difference (trange)
|
|
* must be ginned up to correspond to the change reported
|
|
* in the other file
|
|
*/
|
|
keep(i,rold,rnew)
|
|
struct range *rold, *rnew;
|
|
{
|
|
register delta;
|
|
struct range trange;
|
|
delta = last[3] - last[i];
|
|
trange.from = rnew->from - delta;
|
|
trange.to = rnew->to - delta;
|
|
change(i,&trange,1);
|
|
}
|
|
|
|
/* skip to just befor line number from in file i
|
|
* if "pr" is nonzero, print all skipped stuff
|
|
* w with string pr as a prefix
|
|
*/
|
|
skip(i,from,pr)
|
|
char *pr;
|
|
{
|
|
register j,n;
|
|
for(n=0;cline[i]<from-1;n+=j) {
|
|
if((j=getline(fp[i]))==0)
|
|
trouble();
|
|
if(pr)
|
|
printf("%s%s",pr,line);
|
|
cline[i]++;
|
|
}
|
|
return(n);
|
|
}
|
|
|
|
/* return 1 or 0 according as the old range
|
|
* (in file 1) contains exactly the same data
|
|
* as the new range (in file 2)
|
|
*/
|
|
duplicate(r1,r2)
|
|
struct range *r1, *r2;
|
|
{
|
|
register c,d;
|
|
register nchar;
|
|
int nline;
|
|
if(r1->to-r1->from != r2->to-r2->from)
|
|
return(0);
|
|
skip(0,r1->from,(char *)0);
|
|
skip(1,r2->from,(char *)0);
|
|
nchar = 0;
|
|
for(nline=0;nline<r1->to-r1->from;nline++) {
|
|
do {
|
|
c = getc(fp[0]);
|
|
d = getc(fp[1]);
|
|
if(c== -1||d== -1)
|
|
trouble();
|
|
nchar++;
|
|
if(c!=d) {
|
|
repos(nchar);
|
|
return(0);
|
|
}
|
|
} while(c!= '\n');
|
|
}
|
|
repos(nchar);
|
|
return(1);
|
|
}
|
|
|
|
repos(nchar)
|
|
{
|
|
register i;
|
|
for(i=0;i<2;i++)
|
|
fseek(fp[i], (long)-nchar, 1);
|
|
}
|
|
|
|
trouble()
|
|
{
|
|
fprintf(stderr,"diff3: logic error\n");
|
|
abort();
|
|
}
|
|
|
|
/* collect an editing script for later regurgitation
|
|
*/
|
|
edit(diff,dup,j)
|
|
struct diff *diff;
|
|
{
|
|
if(((dup+1)&eflag)==0)
|
|
return(j);
|
|
j++;
|
|
de[j].old.from = diff->old.from;
|
|
de[j].old.to = diff->old.to;
|
|
de[j].new.from = de[j-1].new.to
|
|
+skip(2,diff->new.from,(char *)0);
|
|
de[j].new.to = de[j].new.from
|
|
+skip(2,diff->new.to,(char *)0);
|
|
return(j);
|
|
}
|
|
|
|
/* regurgitate */
|
|
edscript(n)
|
|
{
|
|
register j,k;
|
|
char block[BUFSIZ];
|
|
|
|
for(n=n; n>0; n--) {
|
|
prange(&de[n].old);
|
|
fseek(fp[2], (long)de[n].new.from, 0);
|
|
for(k=de[n].new.to-de[n].new.from;k>0;k-= j) {
|
|
j = k>BUFSIZ?BUFSIZ:k;
|
|
if(fread(block,1,j,fp[2])!=j)
|
|
trouble();
|
|
fwrite(block, 1, j, stdout);
|
|
}
|
|
printf(".\n");
|
|
}
|
|
}
|