blob: 1aeebe1d96807dc0b4c62ebd9ad6b32d88dc6edf
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * cat -v implementation for busybox |
4 | * |
5 | * Copyright (C) 2006 Rob Landley <rob@landley.net> |
6 | * |
7 | * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
8 | */ |
9 | |
10 | /* See "Cat -v considered harmful" at |
11 | * http://cm.bell-labs.com/cm/cs/doc/84/kp.ps.gz */ |
12 | |
13 | //config:config CATV |
14 | //config: bool "catv" |
15 | //config: default y |
16 | //config: help |
17 | //config: Display nonprinting characters as escape sequences (like some |
18 | //config: implementations' cat -v option). |
19 | |
20 | //applet:IF_CATV(APPLET(catv, BB_DIR_BIN, BB_SUID_DROP)) |
21 | |
22 | //kbuild:lib-$(CONFIG_CATV) += catv.o |
23 | |
24 | //usage:#define catv_trivial_usage |
25 | //usage: "[-etv] [FILE]..." |
26 | //usage:#define catv_full_usage "\n\n" |
27 | //usage: "Display nonprinting characters as ^x or M-x\n" |
28 | //usage: "\n -e End each line with $" |
29 | //usage: "\n -t Show tabs as ^I" |
30 | //usage: "\n -v Don't use ^x or M-x escapes" |
31 | |
32 | #include "libbb.h" |
33 | #include "common_bufsiz.h" |
34 | |
35 | #define CATV_OPT_e (1<<0) |
36 | #define CATV_OPT_t (1<<1) |
37 | #define CATV_OPT_v (1<<2) |
38 | struct BUG_const_mismatch { |
39 | char BUG_const_mismatch[ |
40 | CATV_OPT_e == VISIBLE_ENDLINE && CATV_OPT_t == VISIBLE_SHOW_TABS |
41 | ? 1 : -1 |
42 | ]; |
43 | }; |
44 | |
45 | int catv_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
46 | int catv_main(int argc UNUSED_PARAM, char **argv) |
47 | { |
48 | int retval = EXIT_SUCCESS; |
49 | int fd; |
50 | unsigned opts; |
51 | opts = getopt32(argv, "etv"); |
52 | argv += optind; |
53 | #if 0 /* These consts match, we can just pass "opts" to visible() */ |
54 | if (opts & CATV_OPT_e) |
55 | flags |= VISIBLE_ENDLINE; |
56 | if (opts & CATV_OPT_t) |
57 | flags |= VISIBLE_SHOW_TABS; |
58 | #endif |
59 | |
60 | /* Read from stdin if there's nothing else to do. */ |
61 | if (!argv[0]) |
62 | *--argv = (char*)"-"; |
63 | |
64 | #define read_buf bb_common_bufsiz1 |
65 | setup_common_bufsiz(); |
66 | do { |
67 | fd = open_or_warn_stdin(*argv); |
68 | if (fd < 0) { |
69 | retval = EXIT_FAILURE; |
70 | continue; |
71 | } |
72 | for (;;) { |
73 | int i, res; |
74 | |
75 | res = read(fd, read_buf, COMMON_BUFSIZE); |
76 | if (res < 0) |
77 | retval = EXIT_FAILURE; |
78 | if (res <= 0) |
79 | break; |
80 | for (i = 0; i < res; i++) { |
81 | unsigned char c = read_buf[i]; |
82 | if (opts & CATV_OPT_v) { |
83 | putchar(c); |
84 | } else { |
85 | char buf[sizeof("M-^c")]; |
86 | visible(c, buf, opts); |
87 | fputs(buf, stdout); |
88 | } |
89 | } |
90 | } |
91 | if (ENABLE_FEATURE_CLEAN_UP && fd) |
92 | close(fd); |
93 | } while (*++argv); |
94 | |
95 | fflush_stdout_and_exit(retval); |
96 | } |
97 |