| 1 | #include <assert.h> |
| 2 | #include <ctype.h> |
| 3 | #include <errno.h> |
| 4 | #include <fcntl.h> |
| 5 | #include <signal.h> |
| 6 | #include <stdio.h> |
| 7 | #include <stdlib.h> |
| 8 | #include <string.h> |
| 9 | #include <time.h> |
| 10 | #include <unistd.h> |
| 11 | |
| 12 | #include "khatus_lib_log.h" |
| 13 | #include "khatus_lib_time.h" |
| 14 | |
| 15 | #define usage(...) {print_usage(); fprintf(stderr, "Error:\n " __VA_ARGS__); exit(EXIT_FAILURE);} |
| 16 | |
| 17 | #define MAX_LEN 20 |
| 18 | #define END_OF_MESSAGE '\n' |
| 19 | |
| 20 | char *argv0 = NULL; |
| 21 | |
| 22 | double opt_interval = 1.0; |
| 23 | char *opt_fmt = "%a %b %d %H:%M:%S"; |
| 24 | char *fifo_name = NULL; |
| 25 | |
| 26 | void |
| 27 | print_usage() |
| 28 | { |
| 29 | printf( |
| 30 | "%s: [OPT ...] FIFO\n" |
| 31 | "\n" |
| 32 | "FIFO = string # path to fifo file\n" |
| 33 | "OPT = -i int # interval\n" |
| 34 | " | -f string # format string\n" |
| 35 | " | -h # help message (i.e. what you're reading now :) )\n", |
| 36 | argv0); |
| 37 | } |
| 38 | |
| 39 | void |
| 40 | opt_parse(int argc, char **argv) |
| 41 | { |
| 42 | char c; |
| 43 | |
| 44 | while ((c = getopt(argc, argv, "f:i:h")) != -1) |
| 45 | switch (c) { |
| 46 | case 'f': |
| 47 | opt_fmt = calloc(strlen(optarg), sizeof(char)); |
| 48 | strcpy(opt_fmt, optarg); |
| 49 | break; |
| 50 | case 'i': |
| 51 | opt_interval = atof(optarg); |
| 52 | break; |
| 53 | case 'h': |
| 54 | print_usage(); |
| 55 | exit(EXIT_SUCCESS); |
| 56 | case '?': |
| 57 | if (optopt == 'f' || optopt == 'i') |
| 58 | fprintf(stderr, |
| 59 | "Option -%c requires an argument.\n", |
| 60 | optopt); |
| 61 | else if (isprint(optopt)) |
| 62 | fprintf (stderr, |
| 63 | "Unknown option `-%c'.\n", |
| 64 | optopt); |
| 65 | else |
| 66 | fprintf(stderr, |
| 67 | "Unknown option character `\\x%x'.\n", |
| 68 | optopt); |
| 69 | exit(EXIT_FAILURE); |
| 70 | default: |
| 71 | assert(0); |
| 72 | } |
| 73 | fifo_name = argv[optind]; |
| 74 | debug("fifo_name: %s\n", fifo_name); |
| 75 | if (!fifo_name) |
| 76 | usage("No filename was provided\n"); |
| 77 | } |
| 78 | |
| 79 | int |
| 80 | main(int argc, char **argv) |
| 81 | { |
| 82 | argv0 = argv[0]; |
| 83 | |
| 84 | time_t t; |
| 85 | struct timespec ti; |
| 86 | char buf[MAX_LEN]; |
| 87 | |
| 88 | int fd = -1; |
| 89 | |
| 90 | int n = 0; /* written */ |
| 91 | int r = 0; /* remaining */ |
| 92 | int i = 0; /* buffer position */ |
| 93 | |
| 94 | opt_parse(argc, argv); |
| 95 | |
| 96 | signal(SIGPIPE, SIG_IGN); /* Handling manually */ |
| 97 | |
| 98 | memset(buf, '\0', MAX_LEN); |
| 99 | ti = timespec_of_float(opt_interval); |
| 100 | for (;;) { |
| 101 | debug("openning \"%s\"\n", fifo_name); |
| 102 | fd = open(fifo_name, O_WRONLY); |
| 103 | if (fd < 0) |
| 104 | fatal("Failed to open FIFO file: \"%s\". Error: %s\n", |
| 105 | fifo_name, |
| 106 | strerror(errno)); |
| 107 | debug("openned. fd: %d\n", fd); |
| 108 | t = time(NULL); |
| 109 | strftime(buf, MAX_LEN, opt_fmt, localtime(&t)); |
| 110 | r = strlen(buf); |
| 111 | buf[r] = END_OF_MESSAGE; |
| 112 | for (i = 0; (n = write(fd, buf + i++, 1)) && r; r--) |
| 113 | ; |
| 114 | if (n < 0) |
| 115 | switch (errno) { |
| 116 | case EPIPE: |
| 117 | error("Broken pipe. Msg buf: %s\n", buf); |
| 118 | break; |
| 119 | default: |
| 120 | fatal( |
| 121 | "Failed to write to %s. " |
| 122 | "Err num: %d, Err msg: %s\n", |
| 123 | fifo_name, |
| 124 | errno, |
| 125 | strerror(errno)); |
| 126 | } |
| 127 | if (close(fd) < 0) |
| 128 | fatal("Failed to close %s. Err num: %d, Err msg: %s\n", |
| 129 | fifo_name, |
| 130 | errno, |
| 131 | strerror(errno)); |
| 132 | fd = -1; |
| 133 | debug("closed. fd: %d\n", fd); |
| 134 | snooze(&ti); |
| 135 | } |
| 136 | return EXIT_SUCCESS; |
| 137 | } |