2.11BSD#431 - /usr/src/bin/diff/diffh.c

   1: #if !defined(lint) && defined(DOSCCS)
   2: static  char sccsid[] = "@(#)diffh.c 4.4 11/27/85";
   3: #endif
   4: 
   5: #include <stdio.h>
   6: #include <ctype.h>
   7: #include <sys/types.h>
   8: #include <sys/stat.h>
   9: 
  10: #define C 3
  11: #define RANGE 30
  12: #define LEN 255
  13: #define INF 16384
  14: 
  15: char *text[2][RANGE];
  16: long lineno[2] = {1, 1};    /*no. of 1st stored line in each file*/
  17: int ntext[2];       /*number of stored lines in each*/
  18: long n0,n1;     /*scan pointer in each*/
  19: int bflag;
  20: int debug = 0;
  21: FILE *file[2];
  22: 
  23:     /* return pointer to line n of file f*/
  24: char *getl(f,n)
  25: long n;
  26: {
  27:     register char *t;
  28:     char *malloc();
  29:     register delta, nt;
  30: again:
  31:     delta = n - lineno[f];
  32:     nt = ntext[f];
  33:     if(delta<0)
  34:         progerr("1");
  35:     if(delta<nt)
  36:         return(text[f][delta]);
  37:     if(delta>nt)
  38:         progerr("2");
  39:     if(nt>=RANGE)
  40:         progerr("3");
  41:     if(feof(file[f]))
  42:         return(NULL);
  43:     t = text[f][nt];
  44:     if(t==0) {
  45:         t = text[f][nt] = malloc(LEN+1);
  46:         if(t==NULL)
  47:             if(hardsynch())
  48:                 goto again;
  49:             else
  50:                 progerr("5");
  51:     }
  52:     t = fgets(t,LEN,file[f]);
  53:     if(t!=NULL)
  54:         ntext[f]++;
  55:     return(t);
  56: }
  57: 
  58:     /*remove thru line n of file f from storage*/
  59: clrl(f,n)
  60: long n;
  61: {
  62:     register i,j;
  63:     j = n-lineno[f]+1;
  64:     for(i=0;i+j<ntext[f];i++)
  65:         movstr(text[f][i+j],text[f][i]);
  66:     lineno[f] = n+1;
  67:     ntext[f] -= j;
  68: }
  69: 
  70: movstr(s,t)
  71: register char *s, *t;
  72: {
  73:     while(*t++= *s++)
  74:         continue;
  75: }
  76: 
  77: main(argc,argv)
  78: char **argv;
  79: {
  80:     char *s0,*s1;
  81:     FILE *dopen();
  82:     register int status = 0;
  83: 
  84:     while(*argv[1]=='-') {
  85:         argc--;
  86:         argv++;
  87:         while(*++argv[0])
  88:             if(*argv[0]=='b')
  89:                 bflag++;
  90:     }
  91:     if(argc!=3)
  92:         error("must have 2 file arguments","");
  93:     file[0] = dopen(argv[1],argv[2]);
  94:     file[1] = dopen(argv[2],argv[1]);
  95:     for(;;) {
  96:         s0 = getl(0,++n0);
  97:         s1 = getl(1,++n1);
  98:         if(s0==NULL||s1==NULL)
  99:             break;
 100:         if(cmp(s0,s1)!=0) {
 101:             if(!easysynch()&&!hardsynch())
 102:                 progerr("5");
 103:             status = 1;
 104:         } else {
 105:             clrl(0,n0);
 106:             clrl(1,n1);
 107:         }
 108:     }
 109:     if(s0==NULL&&s1==NULL)
 110:         exit(status);
 111:     if(s0==NULL)
 112:         output(-1,INF);
 113:     if(s1==NULL)
 114:         output(INF,-1);
 115:     exit(1);
 116: }
 117: 
 118:     /* synch on C successive matches*/
 119: easysynch()
 120: {
 121:     int i,j;
 122:     register k,m;
 123:     char *s0,*s1;
 124:     for(i=j=1;i<RANGE&&j<RANGE;i++,j++) {
 125:         s0 = getl(0,n0+i);
 126:         if(s0==NULL)
 127:             return(output(INF,INF));
 128:         for(k=C-1;k<j;k++) {
 129:             for(m=0;m<C;m++)
 130:                 if(cmp(getl(0,n0+i-m),
 131:                     getl(1,n1+k-m))!=0)
 132:                     goto cont1;
 133:             return(output(i-C,k-C));
 134: cont1:          ;
 135:         }
 136:         s1 = getl(1,n1+j);
 137:         if(s1==NULL)
 138:             return(output(INF,INF));
 139:         for(k=C-1;k<=i;k++) {
 140:             for(m=0;m<C;m++)
 141:                 if(cmp(getl(0,n0+k-m),
 142:                     getl(1,n1+j-m))!=0)
 143:                     goto cont2;
 144:             return(output(k-C,j-C));
 145: cont2:          ;
 146:         }
 147:     }
 148:     return(0);
 149: }
 150: 
 151: output(a,b)
 152: {
 153:     register i;
 154:     char *s;
 155:     if(a<0)
 156:         change(n0-1,0,n1,b,"a");
 157:     else if(b<0)
 158:         change(n0,a,n1-1,0,"d");
 159:     else
 160:         change(n0,a,n1,b,"c");
 161:     for(i=0;i<=a;i++) {
 162:         s = getl(0,n0+i);
 163:         if(s==NULL)
 164:             break;
 165:         printf("< %s",s);
 166:         clrl(0,n0+i);
 167:     }
 168:     n0 += i-1;
 169:     if(a>=0&&b>=0)
 170:         printf("---\n");
 171:     for(i=0;i<=b;i++) {
 172:         s = getl(1,n1+i);
 173:         if(s==NULL)
 174:             break;
 175:         printf("> %s",s);
 176:         clrl(1,n1+i);
 177:     }
 178:     n1 += i-1;
 179:     return(1);
 180: }
 181: 
 182: change(a,b,c,d,s)
 183: long a,c;
 184: char *s;
 185: {
 186:     range(a,b);
 187:     printf("%s",s);
 188:     range(c,d);
 189:     printf("\n");
 190: }
 191: 
 192: range(a,b)
 193: long a;
 194: {
 195:     if(b==INF)
 196:         printf("%ld,$",a);
 197:     else if(b==0)
 198:         printf("%ld",a);
 199:     else
 200:         printf("%ld,%ld",a,a+b);
 201: }
 202: 
 203: cmp(s,t)
 204: char *s,*t;
 205: {
 206:     if(debug)
 207:         printf("%s:%s\n",s,t);
 208:     for(;;){
 209:         if(bflag&&isspace(*s)&&isspace(*t)) {
 210:             while(isspace(*++s)) ;
 211:             while(isspace(*++t)) ;
 212:         }
 213:         if(*s!=*t||*s==0)
 214:             break;
 215:         s++;
 216:         t++;
 217:     }
 218:     return(*s-*t);
 219: }
 220: 
 221: FILE *dopen(f1,f2)
 222: char *f1,*f2;
 223: {
 224:     FILE *f;
 225:     char b[100],*bptr,*eptr;
 226:     struct stat statbuf;
 227:     if(cmp(f1,"-")==0)
 228:         if(cmp(f2,"-")==0)
 229:             error("can't do - -","");
 230:         else
 231:             return(stdin);
 232:     if(stat(f1,&statbuf)==-1)
 233:         error("can't access ",f1);
 234:     if((statbuf.st_mode&S_IFMT)==S_IFDIR) {
 235:         for(bptr=b;*bptr= *f1++;bptr++) ;
 236:         *bptr++ = '/';
 237:         for(eptr=f2;*eptr;eptr++)
 238:             if(*eptr=='/'&&eptr[1]!=0&&eptr[1]!='/')
 239:                 f2 = eptr+1;
 240:         while(*bptr++= *f2++) ;
 241:         f1 = b;
 242:     }
 243:     f = fopen(f1,"r");
 244:     if(f==NULL)
 245:         error("can't open",f1);
 246:     return(f);
 247: }
 248: 
 249: 
 250: progerr(s)
 251: char *s;
 252: {
 253:     error("program error ",s);
 254: }
 255: 
 256: error(s,t)
 257: char *s,*t;
 258: {
 259:     fprintf(stderr,"diffh: %s%s\n",s,t);
 260:     exit(2);
 261: }
 262: 
 263:     /*stub for resychronization beyond limits of text buf*/
 264: hardsynch()
 265: {
 266:     change(n0,INF,n1,INF,"c");
 267:     printf("---change record omitted\n");
 268:     error("can't resynchronize","");
 269:     return(0);
 270: }

Defined functions

Defined variables

Defined macros