| 1 | #include <assert.h> |
| 2 | #include <ctype.h> |
| 3 | #include <errno.h> |
| 4 | #include <fcntl.h> |
| 5 | #include <limits.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; |
| 21 | |
| 22 | char path[PATH_MAX]; |
| 23 | |
| 24 | double opt_interval = 1.0; |
| 25 | char *opt_battery = "BAT0"; |
| 26 | char *opt_fifo = NULL; |
| 27 | |
| 28 | void |
| 29 | print_usage() |
| 30 | { |
| 31 | printf( |
| 32 | "%s: [OPT ...] FIFO\n" |
| 33 | "\n" |
| 34 | "FIFO = string # path to fifo file\n" |
| 35 | "OPT = -i int # interval\n" |
| 36 | " | -b string # battery file name from /sys/class/power_supply/\n" |
| 37 | " | -h # help message (i.e. what you're reading now :) )\n", |
| 38 | argv0); |
| 39 | } |
| 40 | |
| 41 | void |
| 42 | opt_parse(int argc, char **argv) |
| 43 | { |
| 44 | char c; |
| 45 | |
| 46 | while ((c = getopt(argc, argv, "f:i:h")) != -1) |
| 47 | switch (c) { |
| 48 | case 'f': |
| 49 | opt_battery = calloc(strlen(optarg), sizeof(char)); |
| 50 | strcpy(opt_battery, optarg); |
| 51 | break; |
| 52 | case 'i': |
| 53 | opt_interval = atof(optarg); |
| 54 | break; |
| 55 | case 'h': |
| 56 | print_usage(); |
| 57 | exit(EXIT_SUCCESS); |
| 58 | case '?': |
| 59 | if (optopt == 'f' || optopt == 'i') |
| 60 | fprintf(stderr, |
| 61 | "Option -%c requires an argument.\n", |
| 62 | optopt); |
| 63 | else if (isprint(optopt)) |
| 64 | fprintf (stderr, |
| 65 | "Unknown option `-%c'.\n", |
| 66 | optopt); |
| 67 | else |
| 68 | fprintf(stderr, |
| 69 | "Unknown option character `\\x%x'.\n", |
| 70 | optopt); |
| 71 | exit(EXIT_FAILURE); |
| 72 | default: |
| 73 | assert(0); |
| 74 | } |
| 75 | opt_fifo = argv[optind]; |
| 76 | debug("opt_fifo: %s\n", opt_fifo); |
| 77 | if (!opt_fifo) |
| 78 | usage("No filename was provided\n"); |
| 79 | } |
| 80 | |
| 81 | void |
| 82 | loop(struct timespec *ti, char *fifo, char *buf, int fun(char *)) |
| 83 | { |
| 84 | int fd = -1; |
| 85 | int w = -1; /* written */ |
| 86 | int r = -1; /* remaining */ |
| 87 | int i = -1; /* buffer position */ |
| 88 | |
| 89 | for (;;) { |
| 90 | debug("openning \"%s\"\n", fifo); |
| 91 | fd = open(fifo, O_WRONLY); |
| 92 | if (fd < 0) |
| 93 | fatal("Failed to open FIFO file: \"%s\". Error: %s\n", |
| 94 | fifo, |
| 95 | strerror(errno)); |
| 96 | debug("openned. fd: %d\n", fd); |
| 97 | r = fun(buf); |
| 98 | buf[r] = END_OF_MESSAGE; |
| 99 | for (i = 0; (w = write(fd, buf + i++, 1)) && r; r--) |
| 100 | ; |
| 101 | if (w < 0) |
| 102 | fatal("Failed to write to %s. Err num: %d, Err msg: %s\n", |
| 103 | fifo, |
| 104 | errno, |
| 105 | strerror(errno)); |
| 106 | if (close(fd) < 0) |
| 107 | fatal("Failed to close %s. Err num: %d, Err msg: %s\n", |
| 108 | fifo, |
| 109 | errno, |
| 110 | strerror(errno)); |
| 111 | fd = -1; |
| 112 | debug("closed. fd: %d\n", fd); |
| 113 | snooze(ti); |
| 114 | } |
| 115 | } |
| 116 | |
| 117 | int |
| 118 | read_capacity(char *buf) |
| 119 | { |
| 120 | FILE *fp; |
| 121 | int cap; |
| 122 | |
| 123 | if (!(fp = fopen(path, "r"))) |
| 124 | fatal("Failed to open %s. errno: %d, msg: %s\n", |
| 125 | path, errno, strerror(errno)); |
| 126 | |
| 127 | switch (fscanf(fp, "%d", &cap)) { |
| 128 | case -1: fatal("EOF\n"); |
| 129 | case 0: fatal("Read 0\n"); |
| 130 | case 1: break; |
| 131 | default: assert(0); |
| 132 | } |
| 133 | fclose(fp); |
| 134 | return snprintf(buf, 6, "%3d%%\n", cap); |
| 135 | } |
| 136 | |
| 137 | int |
| 138 | main(int argc, char **argv) |
| 139 | { |
| 140 | argv0 = argv[0]; |
| 141 | |
| 142 | char buf[10]; |
| 143 | char *path_fmt = "/sys/class/power_supply/%s/capacity"; |
| 144 | struct timespec ti = timespec_of_float(opt_interval); |
| 145 | |
| 146 | opt_parse(argc, argv); |
| 147 | |
| 148 | memset(path, '\0', PATH_MAX); |
| 149 | snprintf(path, PATH_MAX, path_fmt, opt_battery); |
| 150 | loop(&ti, opt_fifo, buf, &read_capacity); |
| 151 | } |