Commit | Line | Data |
---|---|---|
77c76070 | 1 | #include <sys/select.h> |
bec93767 | 2 | #include <sys/stat.h> |
4d66492f | 3 | |
9b5ebc12 SK |
4 | #include <assert.h> |
5 | #include <ctype.h> | |
77c76070 | 6 | #include <errno.h> |
c5d1af8c | 7 | #include <fcntl.h> |
9b5ebc12 SK |
8 | #include <stdio.h> |
9 | #include <stdlib.h> | |
10 | #include <string.h> | |
b7487ec5 | 11 | #include <time.h> |
c5d1af8c SK |
12 | #include <unistd.h> |
13 | ||
14 | #include <X11/Xlib.h> | |
9b5ebc12 | 15 | |
b7487ec5 SK |
16 | #include "bsdtimespec.h" |
17 | ||
6626f8ba SK |
18 | #define debug(args...) {fprintf(stderr, "[debug] " args); fflush(stderr);} |
19 | #define info( args...) {fprintf(stderr, "[info] " args); fflush(stderr);} | |
20 | #define error(args...) {fprintf(stderr, "[error] " args); fflush(stderr);} | |
4d66492f SK |
21 | #define fatal(args...) {fprintf(stderr, "[fatal] " args); exit(EXIT_FAILURE);} |
22 | #define usage(args...) {print_usage(); fatal("[usage] " args);} | |
9b5ebc12 | 23 | |
e6c523cd SK |
24 | #define ERRMSG "ERROR" |
25 | ||
26 | static const char errmsg[] = ERRMSG; | |
27 | static const int errlen = sizeof(ERRMSG) - 1; | |
28 | ||
4d66492f | 29 | char *argv0; |
9b5ebc12 | 30 | |
1872c5c1 SK |
31 | /* TODO: Convert fifo list to fifo array. */ |
32 | typedef struct Fifo Fifo; | |
33 | struct Fifo { | |
4d66492f SK |
34 | char *name; |
35 | int fd; | |
9b5ebc12 | 36 | int width; |
4d66492f | 37 | int last_read; |
9b5ebc12 | 38 | int ttl; |
4d66492f | 39 | int pos; /* Position on the output buffer. */ |
1872c5c1 | 40 | Fifo *next; |
9b5ebc12 SK |
41 | }; |
42 | ||
4d66492f SK |
43 | typedef struct Config Config; |
44 | struct Config { | |
9b5ebc12 | 45 | int interval; |
4d66492f | 46 | char * separator; |
1872c5c1 SK |
47 | Fifo * fifos; |
48 | int fifo_count; | |
4d66492f | 49 | int total_width; |
fabb8771 | 50 | int output_to_x_root_window; |
4d66492f SK |
51 | } defaults = { |
52 | .interval = 1, | |
53 | .separator = "|", | |
1872c5c1 SK |
54 | .fifos = NULL, |
55 | .fifo_count = 0, | |
4d66492f | 56 | .total_width = 0, |
fabb8771 | 57 | .output_to_x_root_window = 0, |
9b5ebc12 SK |
58 | }; |
59 | ||
77c76070 | 60 | void |
1872c5c1 | 61 | fifo_print_one(Fifo *f) |
77c76070 SK |
62 | { |
63 | debug( | |
1872c5c1 | 64 | "Fifo " |
77c76070 SK |
65 | "{" |
66 | " name = %s," | |
67 | " fd = %d," | |
68 | " width = %d," | |
69 | " last_read = %d," | |
70 | " ttl = %d," | |
71 | " pos = %d," | |
72 | " next = %p," | |
73 | " }\n", | |
74 | f->name, | |
75 | f->fd, | |
76 | f->width, | |
77 | f->last_read, | |
78 | f->ttl, | |
79 | f->pos, | |
80 | f->next | |
81 | ); | |
82 | } | |
83 | ||
84 | void | |
1872c5c1 | 85 | fifo_print_all(Fifo *head) |
77c76070 | 86 | { |
1872c5c1 SK |
87 | for (Fifo *f = head; f; f = f->next) { |
88 | fifo_print_one(f); | |
77c76070 SK |
89 | } |
90 | } | |
91 | ||
92 | void | |
93 | config_print(Config *c) | |
94 | { | |
95 | debug( | |
96 | "Config " | |
97 | "{" | |
98 | " interval = %d," | |
99 | " separator = %s," | |
1872c5c1 | 100 | " fifo_count = %d," |
77c76070 | 101 | " total_width = %d," |
1872c5c1 | 102 | " fifos = ..." |
77c76070 SK |
103 | " }\n", |
104 | c->interval, | |
105 | c->separator, | |
1872c5c1 | 106 | c->fifo_count, |
77c76070 SK |
107 | c->total_width |
108 | ); | |
1872c5c1 | 109 | fifo_print_all(c->fifos); |
77c76070 | 110 | } |
9b5ebc12 SK |
111 | |
112 | int | |
113 | is_pos_num(char *s) | |
114 | { | |
115 | while (*s != '\0') | |
116 | if (!isdigit(*(s++))) | |
117 | return 0; | |
118 | return 1; | |
119 | } | |
120 | ||
121 | void | |
122 | print_usage() | |
123 | { | |
4d66492f | 124 | assert(argv0); |
9b5ebc12 SK |
125 | fprintf( |
126 | stderr, | |
127 | "\n" | |
4d66492f | 128 | "Usage: %s [OPTION ...] SPEC [SPEC ...]\n" |
9b5ebc12 | 129 | "\n" |
4d66492f SK |
130 | " SPEC = FILE_PATH DATA_WIDTH DATA_TTL\n" |
131 | " FILE_PATH = string\n" | |
132 | " DATA_WIDTH = int (* (positive) number of characters *)\n" | |
133 | " DATA_TTL = int (* (positive) number of seconds *)\n" | |
134 | " OPTION = -i INTERVAL\n" | |
135 | " | -s SEPARATOR\n" | |
01936218 | 136 | " | -x (* Output to X root window *)\n" |
4d66492f SK |
137 | " SEPARATOR = string\n" |
138 | " INTERVAL = int (* (positive) number of seconds *)\n" | |
9b5ebc12 | 139 | "\n", |
4d66492f | 140 | argv0 |
9b5ebc12 SK |
141 | ); |
142 | fprintf( | |
143 | stderr, | |
144 | "Example: %s -i 1 /dev/shm/khatus/khatus_sensor_x 4 10\n" | |
145 | "\n", | |
4d66492f | 146 | argv0 |
9b5ebc12 SK |
147 | ); |
148 | } | |
149 | ||
4d66492f | 150 | void opts_parse_any(Config *, int, char *[], int); /* For mutually-recursive calls. */ |
9b5ebc12 SK |
151 | |
152 | void | |
4d66492f | 153 | parse_opts_opt_i(Config *cfg, int argc, char *argv[], int i) |
9b5ebc12 SK |
154 | { |
155 | if (i < argc) { | |
156 | char *param = argv[i++]; | |
157 | ||
158 | if (is_pos_num(param)) { | |
4d66492f SK |
159 | cfg->interval = atoi(param); |
160 | opts_parse_any(cfg, argc, argv, i); | |
9b5ebc12 SK |
161 | } else { |
162 | usage("Option -i parameter is invalid: \"%s\"\n", param); | |
163 | } | |
164 | } else { | |
165 | usage("Option -i parameter is missing.\n"); | |
166 | } | |
167 | } | |
168 | ||
169 | void | |
4d66492f SK |
170 | parse_opts_opt_s(Config *cfg, int argc, char *argv[], int i) |
171 | { | |
172 | if (i < argc) { | |
3c836bfd | 173 | cfg->separator = calloc((strlen(argv[i]) + 1), sizeof(char)); |
4d66492f SK |
174 | strcpy(cfg->separator, argv[i]); |
175 | opts_parse_any(cfg, argc, argv, ++i); | |
176 | } else { | |
177 | usage("Option -s parameter is missing.\n"); | |
178 | } | |
179 | } | |
180 | ||
4d66492f SK |
181 | void |
182 | parse_opts_opt(Config *cfg, int argc, char *argv[], int i) | |
9b5ebc12 SK |
183 | { |
184 | switch (argv[i][1]) { | |
fb8745ba SK |
185 | case 'i': |
186 | /* TODO: Generic set_int */ | |
187 | parse_opts_opt_i(cfg, argc, argv, ++i); | |
188 | break; | |
189 | case 's': | |
190 | /* TODO: Generic set_str */ | |
191 | parse_opts_opt_s(cfg, argc, argv, ++i); | |
192 | break; | |
193 | case 'x': | |
fabb8771 SK |
194 | cfg->output_to_x_root_window = 1; |
195 | opts_parse_any(cfg, argc, argv, ++i); | |
196 | break; | |
fb8745ba SK |
197 | default : |
198 | usage("Option \"%s\" is invalid\n", argv[i]); | |
9b5ebc12 SK |
199 | } |
200 | } | |
201 | ||
202 | void | |
4d66492f | 203 | parse_opts_spec(Config *cfg, int argc, char *argv[], int i) |
9b5ebc12 SK |
204 | { |
205 | if ((i + 3) > argc) | |
1872c5c1 | 206 | usage("[spec] Parameter(s) missing for fifo \"%s\".\n", argv[i]); |
9b5ebc12 SK |
207 | |
208 | char *n = argv[i++]; | |
209 | char *w = argv[i++]; | |
210 | char *t = argv[i++]; | |
211 | ||
212 | if (!is_pos_num(w)) | |
1872c5c1 | 213 | usage("[spec] Invalid width: \"%s\", for fifo \"%s\"\n", w, n); |
9b5ebc12 | 214 | if (!is_pos_num(t)) |
1872c5c1 SK |
215 | usage("[spec] Invalid TTL: \"%s\", for fifo \"%s\"\n", t, n); |
216 | Fifo *f = calloc(1, sizeof(struct Fifo)); | |
9b5ebc12 | 217 | if (f) { |
4d66492f SK |
218 | f->name = n; |
219 | f->fd = -1; | |
220 | f->width = atoi(w); | |
221 | f->ttl = atoi(t); | |
222 | f->last_read = 0; | |
223 | f->pos = cfg->total_width; | |
1872c5c1 | 224 | f->next = cfg->fifos; |
4d66492f | 225 | |
1872c5c1 | 226 | cfg->fifos = f; |
4d66492f | 227 | cfg->total_width += f->width; |
1872c5c1 | 228 | cfg->fifo_count++; |
9b5ebc12 | 229 | } else { |
4d66492f | 230 | fatal("[memory] Allocation failure."); |
9b5ebc12 | 231 | } |
4d66492f | 232 | opts_parse_any(cfg, argc, argv, i); |
9b5ebc12 SK |
233 | } |
234 | ||
235 | void | |
4d66492f | 236 | opts_parse_any(Config *cfg, int argc, char *argv[], int i) |
9b5ebc12 SK |
237 | { |
238 | if (i < argc) { | |
239 | switch (argv[i][0]) { | |
fb8745ba SK |
240 | case '-': |
241 | parse_opts_opt(cfg, argc, argv, i); | |
242 | break; | |
243 | default : | |
244 | parse_opts_spec(cfg, argc, argv, i); | |
4d66492f SK |
245 | } |
246 | } | |
247 | } | |
248 | ||
249 | void | |
5400b86f | 250 | opts_parse(Config *cfg, int argc, char *argv[]) |
4d66492f SK |
251 | { |
252 | opts_parse_any(cfg, argc, argv, 1); | |
253 | ||
1872c5c1 SK |
254 | Fifo *last = cfg->fifos; |
255 | cfg->fifos = NULL; | |
256 | for (Fifo *f = last; f; ) { | |
257 | Fifo *next = f->next; | |
258 | f->next = cfg->fifos; | |
259 | cfg->fifos = f; | |
4d66492f SK |
260 | f = next; |
261 | } | |
262 | } | |
263 | ||
e6c523cd | 264 | void |
69b75a40 | 265 | fifo_read_error(Fifo *f, char *buf) |
e6c523cd SK |
266 | { |
267 | char *b; | |
268 | int i; | |
269 | ||
270 | b = buf + f->pos; | |
271 | /* Copy as much of the error message as possible. | |
272 | * EXCLUDING the reminating \0. */ | |
273 | for (i = 0; i < errlen && i < f->width; i++) | |
274 | b[i] = errmsg[i]; | |
275 | /* Any remaining slots: */ | |
276 | for (; i < f->width; i++) | |
277 | b[i] = '_'; | |
278 | } | |
279 | ||
77c76070 | 280 | void |
69b75a40 | 281 | fifo_read_one(Fifo *f, char *buf) |
77c76070 | 282 | { |
3efcce25 SK |
283 | ssize_t current; |
284 | ssize_t total; | |
77c76070 | 285 | char *b; |
3efcce25 | 286 | char c; |
77c76070 | 287 | |
3efcce25 SK |
288 | current = 0; |
289 | total = 0; | |
290 | c = '\0'; | |
77c76070 | 291 | b = buf + f->pos; |
3efcce25 SK |
292 | while ((current = read(f->fd, &c, 1)) && c != '\n' && c != '\0' && total++ < f->width) |
293 | *b++ = c; | |
e6c523cd | 294 | if (current == -1) { |
3efcce25 | 295 | error("Failed to read: \"%s\". Error: %s\n", f->name, strerror(errno)); |
69b75a40 | 296 | fifo_read_error(f, buf); |
7fb02106 SK |
297 | } else |
298 | while (total++ < f->width) | |
299 | *b++ = ' '; | |
6c29392d | 300 | /* TODO Record timestamp read */ |
77c76070 SK |
301 | close(f->fd); |
302 | f->fd = -1; | |
303 | } | |
304 | ||
4d66492f | 305 | void |
69b75a40 | 306 | fifo_read_all(Config *cfg, char *buf) |
4d66492f | 307 | { |
77c76070 | 308 | fd_set fds; |
bfab34f8 | 309 | int maxfd = -1; |
77c76070 | 310 | int ready; |
bec93767 | 311 | struct stat st; |
77c76070 SK |
312 | |
313 | FD_ZERO(&fds); | |
1872c5c1 | 314 | for (Fifo *f = cfg->fifos; f; f = f->next) { |
bec93767 | 315 | /* TODO: Create the FIFO if it doesn't already exist. */ |
e6c523cd SK |
316 | if (lstat(f->name, &st) < 0) { |
317 | error("Cannot stat \"%s\". Error: %s\n", f->name, strerror(errno)); | |
69b75a40 | 318 | fifo_read_error(f, buf); |
e6c523cd SK |
319 | continue; |
320 | } | |
321 | if (!(st.st_mode & S_IFIFO)) { | |
322 | error("\"%s\" is not a FIFO\n", f->name); | |
69b75a40 | 323 | fifo_read_error(f, buf); |
e6c523cd SK |
324 | continue; |
325 | } | |
77c76070 | 326 | debug("opening: %s\n", f->name); |
4d66492f | 327 | if (f->fd < 0) |
77c76070 | 328 | f->fd = open(f->name, O_RDONLY | O_NONBLOCK); |
e6c523cd | 329 | if (f->fd == -1) { |
1872c5c1 | 330 | /* TODO: Consider backing off retries for failed fifos. */ |
e6c523cd | 331 | error("Failed to open \"%s\"\n", f->name); |
69b75a40 | 332 | fifo_read_error(f, buf); |
e6c523cd SK |
333 | continue; |
334 | } | |
77c76070 SK |
335 | if (f->fd > maxfd) |
336 | maxfd = f->fd; | |
337 | FD_SET(f->fd, &fds); | |
338 | } | |
339 | debug("selecting...\n"); | |
340 | ready = select(maxfd + 1, &fds, NULL, NULL, NULL); | |
341 | debug("ready: %d\n", ready); | |
342 | assert(ready != 0); | |
343 | if (ready < 0) | |
344 | fatal("%s", strerror(errno)); | |
1872c5c1 | 345 | for (Fifo *f = cfg->fifos; f; f = f->next) { |
77c76070 SK |
346 | if (FD_ISSET(f->fd, &fds)) { |
347 | debug("reading: %s\n", f->name); | |
69b75a40 | 348 | fifo_read_one(f, buf); |
9b5ebc12 SK |
349 | } |
350 | } | |
351 | } | |
352 | ||
b7487ec5 SK |
353 | void |
354 | snooze(struct timespec *t) | |
355 | { | |
356 | struct timespec remainder; | |
357 | int result; | |
358 | ||
359 | result = nanosleep(t, &remainder); | |
360 | ||
361 | if (result < 0) { | |
362 | if (errno == EINTR) { | |
363 | info( | |
364 | "nanosleep interrupted. Remainder: " | |
365 | "{ tv_sec = %ld, tv_nsec = %ld }", | |
366 | remainder.tv_sec, remainder.tv_nsec); | |
367 | /* No big deal if we occasionally sleep less, | |
368 | * so not attempting to correct after an interruption. | |
369 | */ | |
370 | } else { | |
371 | fatal("nanosleep: %s\n", strerror(errno)); | |
372 | } | |
373 | } | |
374 | } | |
375 | ||
9b5ebc12 | 376 | int |
4d66492f | 377 | main(int argc, char *argv[]) |
9b5ebc12 | 378 | { |
f277f405 | 379 | int width = 0; |
1872c5c1 | 380 | int nfifos = 0; |
f277f405 | 381 | int seplen = 0; |
4d66492f | 382 | int prefix = 0; |
e6c523cd | 383 | int errors = 0; |
4d66492f | 384 | char *buf; |
a6d4c9c3 SK |
385 | Config cfg0 = defaults; |
386 | Config *cfg = &cfg0; | |
bfab34f8 | 387 | Display *display = NULL; |
e6c523cd | 388 | struct stat st; |
b7487ec5 SK |
389 | struct timespec |
390 | t0, /* time stamp. before reading fifos */ | |
391 | t1, /* time stamp. after reading fifos */ | |
392 | ti, /* time interval desired (t1 - t0) */ | |
393 | td, /* time interval measured (t1 - t0) */ | |
394 | tc; /* time interval correction (ti - td) when td < ti */ | |
4d66492f SK |
395 | |
396 | argv0 = argv[0]; | |
397 | ||
5400b86f | 398 | opts_parse(cfg, argc, argv); |
4d66492f | 399 | debug("argv0 = %s\n", argv0); |
77c76070 | 400 | config_print(cfg); |
b7487ec5 SK |
401 | |
402 | /* TODO: Support interval < 1. i.e. implement timespec_of_float */ | |
403 | ti.tv_sec = cfg->interval; | |
404 | ti.tv_nsec = 0; | |
405 | ||
1872c5c1 SK |
406 | if (cfg->fifos == NULL) |
407 | usage("No fifo specs were given!\n"); | |
4d66492f | 408 | |
e6c523cd SK |
409 | /* 1st pass to check file existence and type */ |
410 | for (Fifo *f = cfg->fifos; f; f = f->next) { | |
411 | if (lstat(f->name, &st) < 0) { | |
412 | error("Cannot stat \"%s\". Error: %s\n", f->name, strerror(errno)); | |
413 | errors++; | |
414 | continue; | |
415 | } | |
416 | if (!(st.st_mode & S_IFIFO)) { | |
417 | error("\"%s\" is not a FIFO\n", f->name); | |
418 | errors++; | |
419 | continue; | |
420 | } | |
421 | } | |
422 | if (errors) | |
423 | fatal("Encountered errors with the given file paths. See log.\n"); | |
424 | ||
4d66492f SK |
425 | width = cfg->total_width; |
426 | seplen = strlen(cfg->separator); | |
427 | ||
e6c523cd | 428 | /* 2nd pass to make space for separators */ |
1872c5c1 | 429 | for (Fifo *f = cfg->fifos; f; f = f->next) { |
4d66492f SK |
430 | f->pos += prefix; |
431 | prefix += seplen; | |
1872c5c1 | 432 | nfifos++; |
4d66492f | 433 | } |
1872c5c1 | 434 | width += (seplen * (nfifos - 1)); |
3c836bfd | 435 | buf = calloc(1, width + 1); |
4d66492f SK |
436 | if (buf == NULL) |
437 | fatal("[memory] Failed to allocate buffer of %d bytes", width); | |
438 | memset(buf, ' ', width); | |
439 | buf[width] = '\0'; | |
e6c523cd | 440 | /* 3rd pass to set the separators */ |
1872c5c1 | 441 | for (Fifo *f = cfg->fifos; f; f = f->next) { |
4d66492f | 442 | if (f->pos) { /* Skip the first, left-most */ |
77c76070 SK |
443 | /* Copying only seplen ensures we omit the '\0' byte. */ |
444 | strncpy(buf + (f->pos - seplen), cfg->separator, seplen); | |
4d66492f SK |
445 | } |
446 | } | |
447 | ||
fabb8771 SK |
448 | if (cfg->output_to_x_root_window && !(display = XOpenDisplay(NULL))) |
449 | fatal("XOpenDisplay failed with: %p\n", display); | |
805f0d22 | 450 | /* TODO: Handle signals */ |
4d66492f | 451 | for (;;) { |
b7487ec5 SK |
452 | clock_gettime(CLOCK_MONOTONIC, &t0); // FIXME: check errors |
453 | /* TODO: Cache expiration. i.e. use the TTL */ | |
6c29392d | 454 | /* TODO: How to trigger TTL check? On select? Alarm signal? */ |
69b75a40 SK |
455 | /* TODO: Set timeout on fifo_read_all based on diff of last time of |
456 | * fifo_read_all and desired time of next TTL check. | |
b7487ec5 SK |
457 | */ |
458 | /* TODO: How long to wait on IO? Max TTL? */ | |
69b75a40 | 459 | fifo_read_all(cfg, buf); |
fabb8771 SK |
460 | if (cfg->output_to_x_root_window) { |
461 | if (XStoreName(display, DefaultRootWindow(display), buf) < 0) | |
462 | fatal("XStoreName failed.\n"); | |
463 | XFlush(display); | |
464 | } else { | |
465 | puts(buf); | |
466 | fflush(stdout); | |
467 | } | |
b7487ec5 SK |
468 | clock_gettime(CLOCK_MONOTONIC, &t1); // FIXME: check errors |
469 | timespecsub(&t1, &t0, &td); | |
470 | debug("td {tv_sec = %ld, tv_nsec = %ld}\n", td.tv_sec, td.tv_nsec); | |
471 | if (timespeccmp(&td, &ti, <)) { | |
472 | /* Pushback on data producers by refusing to read the | |
473 | * pipe more frequently than the interval. | |
474 | */ | |
475 | timespecsub(&ti, &td, &tc); | |
476 | debug("snooze YES\n"); | |
477 | snooze(&tc); | |
478 | } else | |
479 | debug("snooze NO\n"); | |
4d66492f | 480 | } |
3d7e82a8 SK |
481 | |
482 | return EXIT_SUCCESS; | |
9b5ebc12 | 483 | } |