1 /* cmp.c - Compare two files.
2 *
3 * Copyright 2012 Timothy Elliott <tle@holymonkey.com>
4 *
5 * See http://opengroup.org/onlinepubs/9699919799/utilities/cmp.html
6
7 USE_CMP(NEWTOY(cmp, "<2>2ls(silent)(quiet)[!ls]", TOYFLAG_USR|TOYFLAG_BIN|TOYFLAG_ARGFAIL(2)))
8
9 config CMP
10 bool "cmp"
11 default y
12 help
13 usage: cmp [-l] [-s] FILE1 FILE2
14
15 Compare the contents of two files.
16
17 -l Show all differing bytes
18 -s Silent
19 */
20
21 #define FOR_cmp
22 #include "toys.h"
23
GLOBALS(int fd;char * name;)24 GLOBALS(
25 int fd;
26 char *name;
27 )
28
29 static void do_cmp(int fd, char *name)
30 {
31 int i, len1, len2, min_len, size = sizeof(toybuf)/2;
32 long byte_no = 1, line_no = 1;
33 char *buf2 = toybuf+size;
34
35 // First time through, cache the data and return.
36 if (!TT.fd) {
37 TT.name = name;
38 // On return the old filehandle is closed, and this assures that even
39 // if we were called with stdin closed, the new filehandle != 0.
40 TT.fd = dup(fd);
41 return;
42 }
43
44 toys.exitval = 0;
45
46 for (;;) {
47 len1 = readall(TT.fd, toybuf, size);
48 len2 = readall(fd, buf2, size);
49
50 min_len = len1 < len2 ? len1 : len2;
51 for (i=0; i<min_len; i++) {
52 if (toybuf[i] != buf2[i]) {
53 toys.exitval = 1;
54 if (toys.optflags & FLAG_l)
55 printf("%ld %o %o\n", byte_no, toybuf[i], buf2[i]);
56 else {
57 if (!(toys.optflags & FLAG_s))
58 printf("%s %s differ: char %ld, line %ld\n",
59 TT.name, name, byte_no, line_no);
60 goto out;
61 }
62 }
63 byte_no++;
64 if (toybuf[i] == '\n') line_no++;
65 }
66 if (len1 != len2) {
67 if (!(toys.optflags & FLAG_s))
68 fprintf(stderr, "cmp: EOF on %s\n", len1 < len2 ? TT.name : name);
69 toys.exitval = 1;
70 break;
71 }
72 if (len1 < 1) break;
73 }
74 out:
75 if (CFG_TOYBOX_FREE) close(TT.fd);
76 }
77
cmp_main(void)78 void cmp_main(void)
79 {
80 toys.exitval = 2;
81 loopfiles_rw(toys.optargs, O_CLOEXEC|(WARN_ONLY*!(toys.optflags&FLAG_s)), 0,
82 do_cmp);
83 }
84