/* * Copyright (c) 1987 Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms are permitted * provided that: (1) source distributions retain this entire copyright * notice and comment, and (2) distributions including binaries display * the following acknowledgement: ``This product includes software * developed by the University of California, Berkeley and its contributors'' * in the documentation or other materials provided with the distribution * and in all advertising materials mentioning features or use of this * software. Neither the name of the University nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. */ #ifndef lint char copyright[] = "@(#) Copyright (c) 1987, 1990 Regents of the University of California.\n\ All rights reserved.\n"; #endif /* not lint */ #ifndef lint static char sccsid[] = "@(#)cmp.c 5.3 (Berkeley) 6/1/90"; #endif /* not lint */ #include <sys/param.h> #include <sys/file.h> #include <sys/stat.h> #include <stdio.h> #include <ctype.h> #include <errno.h> #define EXITNODIFF 0 #define EXITDIFF 1 #define EXITERR 2 int all, fd1, fd2, silent; u_char buf1[MAXBSIZE], buf2[MAXBSIZE]; char *file1, *file2; main(argc, argv) int argc; char *argv[]; { extern char *optarg; extern int optind; int ch; u_long otoi(); while ((ch = getopt(argc, argv, "-ls")) != EOF) switch (ch) { case 'l': /* print all differences */ all = 1; break; case 's': /* silent run */ silent = 1; break; case '-': /* must be after any flags */ --optind; goto endargs; case '?': default: usage(); } endargs: argv += optind; argc -= optind; if (argc < 2 || argc > 4) usage(); if (all && silent) { fprintf(stderr, "cmp: only one of -l and -s may be specified.\n"); exit(EXITERR); } if (strcmp(file1 = argv[0], "-") == 0) fd1 = 0; else if ((fd1 = open(file1, O_RDONLY, 0)) < 0) error(file1); if (strcmp(file2 = argv[1], "-") == 0) fd2 = 0; else if ((fd2 = open(file2, O_RDONLY, 0)) < 0) error(file2); if (fd1 == fd2) { fprintf(stderr, "cmp: standard input may only be specified once.\n"); exit(EXITERR); } /* handle skip arguments */ if (argc > 2) { skip(otoi(argv[2]), fd1, file1); if (argc == 4) skip(otoi(argv[3]), fd2, file2); } cmp(); /*NOTREACHED*/ } /* * skip -- * skip first part of file */ skip(dist, fd, fname) register u_long dist; register int fd; char *fname; { register int rlen, nread; for (; dist; dist -= rlen) { rlen = MIN(dist, sizeof(buf1)); if ((nread = read(fd, buf1, rlen)) != rlen) { if (nread < 0) error(fname); else endoffile(fname); } } } cmp() { register u_char *p1, *p2; register int cnt, len1, len2; register long byte, line; int dfound = 0; for (byte = 0, line = 1; ; ) { switch (len1 = read(fd1, buf1, MAXBSIZE)) { case -1: error(file1); case 0: /* * read of file 1 just failed, find out * if there's anything left in file 2 */ switch (read(fd2, buf2, 1)) { case -1: error(file2); /* NOTREACHED */ case 0: exit(dfound ? EXITDIFF : EXITNODIFF); /* NOTREACHED */ default: endoffile(file1); break; } } /* * file1 might be stdio, which means that a read of less than * MAXBSIZE might not mean an EOF. So, read whatever we read * from file1 from file2. */ if ((len2 = read(fd2, buf2, len1)) == -1) error(file2); if (bcmp(buf1, buf2, len2)) { if (silent) exit(EXITDIFF); if (all) { dfound = 1; for (p1 = buf1, p2 = buf2, cnt = len2; cnt--; ++p1, ++p2) { ++byte; if (*p1 != *p2) printf("%6ld %3o %3o\n", byte, *p1, *p2); } } else for (p1 = buf1, p2 = buf2; ; ++p1, ++p2) { ++byte; if (*p1 != *p2) { printf("%s %s differ: char %ld, line %ld\n", file1, file2, byte, line); exit(EXITDIFF); } if (*p1 == '\n') ++line; } } else { byte += len2; /* * here's the real performance problem, we've got to * count the stupid lines, which means that -l is a * *much* faster version, i.e., unless you really * *want* to know the line number, run -s or -l. */ if (!silent && !all) for (p1 = buf1, cnt = len2; cnt--; ) if (*p1++ == '\n') ++line; } /* * couldn't read as much from file2 as from file1; checked * here because there might be a difference before we got * to this point, which would have precedence. */ if (len2 < len1) endoffile(file2); } } /* * otoi -- * octal/decimal string to u_long */ u_long otoi(s) register char *s; { register u_long val; register int base; base = (*s == '0') ? 8 : 10; for (val = 0; isdigit(*s); ++s) val = val * base + *s - '0'; return (val); } /* * error -- * print I/O error message and die */ error(filename) char *filename; { extern int errno; char *strerror(); if (!silent) (void) fprintf(stderr, "cmp: %s: %s\n", filename, strerror(errno)); exit(EXITERR); } /* * endoffile -- * print end-of-file message and exit indicating the files were different */ endoffile(filename) char *filename; { /* 32V put this message on stdout, S5 does it on stderr. */ /* POSIX.2 currently does it on stdout-- Hooray! */ if (!silent) (void) printf("cmp: EOF on %s\n", filename); exit(EXITDIFF); } /* * usage -- * print usage and die */ usage() { fputs("usage: cmp [-ls] file1 file2 [skip1] [skip2]\n", stderr); exit(EXITERR); }