/* * Copyright (c) 1987 Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided 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. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. 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 BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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. */ #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[] = "from: @(#)cmp.c 5.3 (Berkeley) 6/1/90";*/ static char rcsid[] = "$Id: cmp.c,v 1.6 1994/03/25 17:07:02 mycroft Exp $"; #endif /* not lint */ #include #include #include #include #include #include #include #include #include #include #define EXITNODIFF 0 #define EXITDIFF 1 #define EXITERR 2 void skip __P(()); __dead void cmp __P(()); __dead void error __P(()); __dead void endoffile __P(()); __dead void usage __P(()); int all, fd1, fd2, silent; u_char buffer1[MAXBSIZE], buffer2[MAXBSIZE]; char *file1, *file2; int main(argc, argv) int argc; char **argv; { int ch; setlocale(LC_ALL, ""); while ((ch = getopt(argc, argv, "ls")) != -1) switch (ch) { case 'l': /* print all differences */ all = 1; break; case 's': /* silent run */ silent = 1; break; case '?': default: usage(); } argv += optind; argc -= optind; if (argc < 2 || argc > 4) usage(); if (all && silent) usage (); 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(strtoul(argv[2], NULL, 0), fd1, file1); if (argc == 4) skip(strtoul(argv[3], NULL, 0), fd2, file2); } cmp(); /*NOTREACHED*/ } /* * skip -- * skip first part of file */ void 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(buffer1)); if ((nread = read(fd, buffer1, rlen)) != rlen) { if (nread < 0) error(fname); else endoffile(fname); } } } void cmp() { register u_char *p1, *p2; u_char *buf1, *buf2; register int cnt; int len = 0, len1 = 0, len2 = 0; register long byte, line; int dfound = 0; for (byte = 0, line = 1; ; ) { len1 -= len; len2 -= len; if (len1) buf1 += len; else switch (len1 = read(fd1, buf1 = buffer1, MAXBSIZE)) { case -1: error(file1); case 0: if (len2) endoffile(file1); /* * read of file 1 just failed, find out * if there's anything left in file 2 */ switch (read(fd2, buf2 = buffer2, 1)) { case -1: error(file2); /* NOTREACHED */ case 0: exit(dfound ? EXITDIFF : EXITNODIFF); /* NOTREACHED */ default: endoffile(file1); break; } } if (len2) buf2 += len; else switch (len2 = read(fd2, buf2 = buffer2, MAXBSIZE)) { case -1: error(file2); case 0: /* * read of file 2 just failed; we know there is * data left in file 1 if we got this far */ endoffile(file2); break; } /* * Either file might be stdio. We compare only the minimum * number of bytes we know are common, then loop back to the * top. This avoids blocking on input if a difference is * found early. */ if (len1 < len2) len = len1; else len = len2; if (memcmp(buf1, buf2, len)) { if (silent) exit(EXITDIFF); if (all) { dfound = 1; for (p1 = buf1, p2 = buf2, cnt = len; 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 += len; /* * 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 = len; cnt--; ) if (*p1++ == '\n') ++line; } } } /* * error -- * print I/O error message and die */ void 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 */ void endoffile(filename) char *filename; { if (!silent) (void) fprintf(stderr, "cmp: EOF on %s\n", filename); exit(EXITDIFF); } /* * usage -- * print usage and die */ void usage() { fputs("usage: cmp [-l | -s] file1 file2 [skip1] [skip2]\n", stderr); exit(EXITERR); }