Commit | Line | Data |
---|---|---|
223bbefb MW |
1 | /* -*- |
2 | * | |
3 | * Like cat, with datestamps | |
4 | */ | |
5 | ||
6 | #include <errno.h> | |
7 | #include <stdio.h> | |
8 | #include <stdlib.h> | |
9 | #include <string.h> | |
10 | #include <time.h> | |
11 | ||
12 | #include <unistd.h> | |
13 | ||
14 | #include <mLib/mdwopt.h> | |
15 | #include <mLib/quis.h> | |
16 | #include <mLib/report.h> | |
17 | ||
18 | static const char *fmt = "%Y-%m-%d %H:%M:%S %Z: "; | |
19 | static struct tm *(*cvt)(const time_t *) = localtime; | |
20 | ||
21 | static void version(void) { pquis(stdout, "$ " VERSION); } | |
22 | static void usage(FILE *fp) | |
23 | { pquis(fp, "Usage: $ [-z] [-f FORMAT] [FILE...]"); } | |
24 | ||
25 | static void help(void) | |
26 | { | |
27 | version(); putchar('\n'); | |
28 | usage(stdout); | |
29 | fputs("\n\ | |
30 | Copy the FILEs (or standard input) to standard output, prefixing each line\n\ | |
31 | with a datestamp.\n\ | |
32 | \n\ | |
33 | -h, --help Show this help text.\n\ | |
34 | -v, --version Show the program's version number.\n\ | |
35 | -u, --usage Show a brief usage message.\n\ | |
36 | \n\ | |
37 | -f, --format=FORMAT Write datestamps using the strftime(3) FORMAT.\n\ | |
38 | -z, --utc, --zulu Use UTC rather than local time for datestamps.\n\ | |
39 | ", stdout); | |
40 | } | |
41 | ||
42 | static void cat(FILE *in) | |
43 | { | |
44 | unsigned ln = 1; | |
45 | time_t t; | |
46 | struct tm *tm; | |
47 | char buf[256]; | |
48 | int ch; | |
49 | ||
50 | for (;;) { | |
51 | if ((ch = getc(in)) == EOF) | |
52 | break; | |
53 | if (ln) { | |
54 | t = time(0); | |
55 | tm = cvt(&t); | |
56 | strftime(buf, sizeof(buf), fmt, tm); | |
57 | fwrite(buf, 1, strlen(buf), stdout); | |
58 | } | |
59 | putchar(ch); | |
60 | ln = (ch == '\n'); | |
61 | } | |
62 | if (!ln) | |
63 | putchar('\n'); | |
64 | } | |
65 | ||
66 | int main(int argc, char *argv[]) | |
67 | { | |
68 | int i; | |
69 | FILE *fp; | |
70 | unsigned f = 0; | |
71 | #define F_BOGUS 1u | |
72 | ||
73 | ego(argv[0]); | |
74 | setvbuf(stdin, 0, _IOLBF, 0); | |
75 | ||
76 | for (;;) { | |
77 | static const struct option opt[] = { | |
78 | { "help", 0, 0, 'h' }, | |
79 | { "version", 0, 0, 'v' }, | |
80 | { "usage", 0, 0, 'u' }, | |
81 | { "format", OPTF_ARGREQ, 0, 'f' }, | |
82 | { "utc", 0, 0, 'z' }, | |
83 | { "zulu", 0, 0, 'z' }, | |
84 | { 0, 0, 0, 0 } | |
85 | }; | |
86 | ||
87 | if ((i = mdwopt(argc, argv, "hvuf:z", opt, 0, 0, 0)) < 0) | |
88 | break; | |
89 | switch (i) { | |
90 | case 'h': | |
91 | help(); | |
92 | exit(0); | |
93 | case 'v': | |
94 | version(); | |
95 | exit(0); | |
96 | case 'u': | |
97 | usage(stdout); | |
98 | exit(0); | |
99 | case 'f': | |
100 | fmt = optarg; | |
101 | break; | |
102 | case 'z': | |
103 | cvt = gmtime; | |
104 | break; | |
105 | default: | |
106 | f |= F_BOGUS; | |
107 | break; | |
108 | } | |
109 | } | |
110 | ||
111 | if (f & F_BOGUS) { | |
112 | usage(stderr); | |
113 | exit(EXIT_FAILURE); | |
114 | } | |
115 | ||
116 | if (optind == argc) { | |
117 | if (isatty(STDIN_FILENO)) | |
118 | die(EXIT_FAILURE, "no arguments, and stdin is a terminal"); | |
119 | cat(stdin); | |
120 | } else for (i = optind; i < argc; i++) { | |
121 | if (strcmp(argv[i], "-") == 0) | |
122 | cat(stdin); | |
123 | else if ((fp = fopen(argv[i], "r")) == 0) { | |
124 | moan("failed to open `%s': %s", argv[i], strerror(errno)); | |
125 | f |= F_BOGUS; | |
126 | } else { | |
127 | cat(fp); | |
128 | fclose(fp); | |
129 | } | |
130 | } | |
131 | ||
132 | if (ferror(stdout) || fflush(stdout) || fclose(stdout)) { | |
133 | moan("error writing output: %s", strerror(errno)); | |
134 | f |= F_BOGUS; | |
135 | } | |
136 | ||
137 | return ((f & F_BOGUS) ? EXIT_FAILURE : 0); | |
841e5aca | 138 | } |