BSD 4 release

[unix-history] / usr / src / cmd / diff / diff.c

static  char sccsid[] = "@(#)diff.c 4.1 10/9/80";

#include "diff.h"
/*
* diff - driver and subroutines
*/

char    diff[] = DIFF;
char    diffh[] = DIFFH;
char    pr[] = PR;
extern  char _sobuf[];

main(argc, argv)
       int argc;
       char **argv;
{
       register char *argp;

       ifdef1 = "FILE1"; ifdef2 = "FILE2";
       status = 2;
       diffargv = argv;
       setbuf(stdout, _sobuf);
       argc--, argv++;
       while (argc > 2 && argv[0][0] == '-') {
               argp = &argv[0][1];
               argv++, argc--;
               while (*argp) switch(*argp++) {

#ifdef notdef
               case 'I':
                       opt = D_IFDEF;
                       wantelses = 0;
                       continue;
               case 'E':
                       opt = D_IFDEF;
                       wantelses = 1;
                       continue;
               case '1':
                       opt = D_IFDEF;
                       ifdef1 = argp;
                       *--argp = 0;
                       continue;
#endif
               case 'D':
                       /* -Dfoo = -E -1 -2foo */
                       wantelses = 1;
                       ifdef1 = "";
                       /* fall through */
#ifdef notdef
               case '2':
#endif
                       opt = D_IFDEF;
                       ifdef2 = argp;
                       *--argp = 0;
                       continue;
               case 'e':
                       opt = D_EDIT;
                       continue;
               case 'f':
                       opt = D_REVERSE;
                       continue;
               case 'b':
                       bflag = 1;
                       continue;
               case 'c':
                       opt = D_CONTEXT;
                       if (isdigit(*argp)) {
                               context = atoi(argp);
                               while (isdigit(*argp))
                                       argp++;
                               if (*argp) {
                                       fprintf(stderr,
                                           "diff: -c: bad count\n");
                                       done();
                               }
                               argp = "";
                       } else
                               context = 3;
                       continue;
               case 'h':
                       hflag++;
                       continue;
               case 'S':
                       if (*argp == 0) {
                               fprintf(stderr, "diff: use -Sstart\n");
                               done();
                       }
                       start = argp;
                       *--argp = 0;            /* don't pass it on */
                       continue;
               case 'r':
                       rflag++;
                       continue;
               case 's':
                       sflag++;
                       continue;
               case 'l':
                       lflag++;
                       continue;
               default:
                       fprintf(stderr, "diff: -%s: unknown option\n",
                           --argp);
                       done();
               }
       }
       if (argc != 2) {
               fprintf(stderr, "diff: two filename arguments required\n");
               done();
       }
       file1 = argv[0];
       file2 = argv[1];
       if (hflag && opt) {
               fprintf(stderr,
                   "diff: -h doesn't support -e, -f, -c, or -I\n");
               done();
       }
       if (!strcmp(file1, "-"))
               stb1.st_mode = S_IFREG;
       else if (stat(file1, &stb1) < 0) {
               fprintf(stderr, "diff: ");
               perror(file1);
               done();
       }
       if (!strcmp(file2, "-"))
               stb2.st_mode = S_IFREG;
       else if (stat(file2, &stb2) < 0) {
               fprintf(stderr, "diff: ");
               perror(file2);
               done();
       }
       if ((stb1.st_mode & S_IFMT) == S_IFDIR &&
           (stb2.st_mode & S_IFMT) == S_IFDIR) {
               diffdir(argv);
       } else
               diffreg();
       done();
}

char *
savestr(cp)
       register char *cp;
{
       register char *dp = malloc(strlen(cp)+1);

       if (dp == 0) {
               fprintf(stderr, "diff: ran out of memory\n");
               done();
       }
       strcpy(dp, cp);
       return (dp);
}

min(a,b)
       int a,b;
{

       return (a < b ? a : b);
}

max(a,b)
       int a,b;
{

       return (a > b ? a : b);
}

done()
{
       unlink(tempfile);
       exit(status);
}

char *
talloc(n)
{
       register char *p;
       p = malloc((unsigned)n);
       if(p!=NULL)
               return(p);
       noroom();
}

char *
ralloc(p,n)     /*compacting reallocation */
char *p;
{
       register char *q;
       char *realloc();
       free(p);
       free(dummy);
       dummy = malloc(1);
       q = realloc(p, (unsigned)n);
       if(q==NULL)
               noroom();
       return(q);
}

noroom()
{
       fprintf(stderr, "diff: files too big, try -h\n");
       done();
}