| 1 | #include <sys/select.h> |
| 2 | #include <sys/stat.h> |
| 3 | |
| 4 | #include <assert.h> |
| 5 | #include <ctype.h> |
| 6 | #include <errno.h> |
| 7 | #include <fcntl.h> |
| 8 | #include <signal.h> |
| 9 | #include <stdio.h> |
| 10 | #include <stdlib.h> |
| 11 | #include <string.h> |
| 12 | #include <time.h> |
| 13 | #include <unistd.h> |
| 14 | |
| 15 | #include <X11/Xlib.h> |
| 16 | |
| 17 | #include "bsdtimespec.h" |
| 18 | #include "khlib_log.h" |
| 19 | #include "khlib_time.h" |
| 20 | |
| 21 | #define usage(...) { \ |
| 22 | print_usage(); \ |
| 23 | fprintf(stderr, "Error:\n " __VA_ARGS__); \ |
| 24 | exit(EXIT_FAILURE); \ |
| 25 | } |
| 26 | #define ERRMSG "ERROR" |
| 27 | |
| 28 | |
| 29 | static const char errmsg[] = ERRMSG; |
| 30 | static const int errlen = sizeof(ERRMSG) - 1; |
| 31 | |
| 32 | char *argv0 = NULL; |
| 33 | int running = 1; |
| 34 | |
| 35 | /* TODO: Convert slot list to slot array. */ |
| 36 | typedef struct Slot Slot; |
| 37 | struct Slot { |
| 38 | char *in_fifo; |
| 39 | int in_fd; |
| 40 | struct timespec in_last_read; |
| 41 | struct timespec out_ttl; |
| 42 | int out_width; |
| 43 | int out_pos_lo; /* Lowest position on the output buffer. */ |
| 44 | int out_pos_cur; /* Current position on the output buffer. */ |
| 45 | int out_pos_hi; /* Highest position on the output buffer. */ |
| 46 | Slot *next; |
| 47 | }; |
| 48 | |
| 49 | typedef struct Config Config; |
| 50 | struct Config { |
| 51 | double interval; |
| 52 | char * separator; |
| 53 | char expiry_character; |
| 54 | Slot * slots; |
| 55 | int slot_count; |
| 56 | int buf_width; |
| 57 | int to_x_root; |
| 58 | }; |
| 59 | |
| 60 | enum read_status { |
| 61 | END_OF_FILE, |
| 62 | END_OF_MESSAGE, |
| 63 | RETRY, |
| 64 | FAILURE |
| 65 | }; |
| 66 | |
| 67 | char * |
| 68 | buf_create(Config *cfg) |
| 69 | { |
| 70 | int seplen; |
| 71 | char *buf; |
| 72 | Slot *s; |
| 73 | |
| 74 | buf = calloc(1, cfg->buf_width + 1); |
| 75 | if (buf == NULL) |
| 76 | khlib_fatal( |
| 77 | "[memory] Failed to allocate buffer of %d bytes", |
| 78 | cfg->buf_width |
| 79 | ); |
| 80 | memset(buf, ' ', cfg->buf_width); |
| 81 | buf[cfg->buf_width] = '\0'; |
| 82 | seplen = strlen(cfg->separator); |
| 83 | /* Set the separators */ |
| 84 | for (s = cfg->slots; s; s = s->next) { |
| 85 | /* Skip the first, left-most */ |
| 86 | if (s->out_pos_lo) { |
| 87 | /* Copying only seplen ensures we omit the '\0' byte. */ |
| 88 | strncpy( |
| 89 | buf + (s->out_pos_lo - seplen), |
| 90 | cfg->separator, |
| 91 | seplen |
| 92 | ); |
| 93 | } |
| 94 | } |
| 95 | return buf; |
| 96 | } |
| 97 | |
| 98 | Slot * |
| 99 | slots_rev(Slot *old) |
| 100 | { |
| 101 | Slot *tmp = NULL; |
| 102 | Slot *new = NULL; |
| 103 | |
| 104 | while (old) { |
| 105 | tmp = old->next; |
| 106 | old->next = new; |
| 107 | new = old; |
| 108 | old = tmp; |
| 109 | } |
| 110 | return new; |
| 111 | } |
| 112 | |
| 113 | void |
| 114 | slot_log(Slot *s) |
| 115 | { |
| 116 | khlib_info("Slot " |
| 117 | "{" |
| 118 | " in_fifo = %s," |
| 119 | " in_fd = %d," |
| 120 | " out_width = %d," |
| 121 | " in_last_read = {tv_sec = %ld, tv_nsec = %ld}" |
| 122 | " out_ttl = {tv_sec = %ld, tv_nsec = %ld}," |
| 123 | " out_pos_lo = %d," |
| 124 | " out_pos_cur = %d," |
| 125 | " out_pos_hi = %d," |
| 126 | " next = %p," |
| 127 | " }\n", |
| 128 | s->in_fifo, |
| 129 | s->in_fd, |
| 130 | s->out_width, |
| 131 | s->in_last_read.tv_sec, |
| 132 | s->in_last_read.tv_nsec, |
| 133 | s->out_ttl.tv_sec, |
| 134 | s->out_ttl.tv_nsec, |
| 135 | s->out_pos_lo, |
| 136 | s->out_pos_cur, |
| 137 | s->out_pos_hi, |
| 138 | s->next |
| 139 | ); |
| 140 | } |
| 141 | |
| 142 | void |
| 143 | slots_log(Slot *head) |
| 144 | { |
| 145 | Slot *s = head; |
| 146 | |
| 147 | for (; s; s = s->next) { |
| 148 | slot_log(s); |
| 149 | } |
| 150 | } |
| 151 | |
| 152 | void |
| 153 | slots_assert_fifos_exist(Slot *s) |
| 154 | { |
| 155 | struct stat st; |
| 156 | int errors = 0; |
| 157 | |
| 158 | for (; s; s = s->next) { |
| 159 | if (lstat(s->in_fifo, &st) < 0) { |
| 160 | khlib_error( |
| 161 | "Cannot stat \"%s\". Error: %s\n", |
| 162 | s->in_fifo, |
| 163 | strerror(errno) |
| 164 | ); |
| 165 | errors++; |
| 166 | continue; |
| 167 | } |
| 168 | if (!(st.st_mode & S_IFIFO)) { |
| 169 | khlib_error("\"%s\" is not a FIFO\n", s->in_fifo); |
| 170 | errors++; |
| 171 | continue; |
| 172 | } |
| 173 | } |
| 174 | if (errors) |
| 175 | khlib_fatal( |
| 176 | "Encountered errors with given file paths. See log.\n" |
| 177 | ); |
| 178 | } |
| 179 | |
| 180 | void |
| 181 | slot_close(Slot *s) |
| 182 | { |
| 183 | close(s->in_fd); |
| 184 | s->in_fd = -1; |
| 185 | s->out_pos_cur = s->out_pos_lo; |
| 186 | } |
| 187 | |
| 188 | void |
| 189 | slots_close(Slot *s) |
| 190 | { |
| 191 | for (; s; s = s->next) |
| 192 | if (s->in_fd > -1) |
| 193 | slot_close(s); |
| 194 | } |
| 195 | |
| 196 | |
| 197 | void |
| 198 | slot_expire(Slot *s, struct timespec t, char expiry_character, char *buf) |
| 199 | { |
| 200 | struct timespec td; |
| 201 | |
| 202 | timespecsub(&t, &(s->in_last_read), &td); |
| 203 | if (timespeccmp(&td, &(s->out_ttl), >=)) { |
| 204 | memset( |
| 205 | buf + s->out_pos_lo, |
| 206 | expiry_character, |
| 207 | s->out_width |
| 208 | ); |
| 209 | khlib_warn("Slot expired: \"%s\"\n", s->in_fifo); |
| 210 | } |
| 211 | } |
| 212 | |
| 213 | void |
| 214 | slot_set_error(Slot *s, char *buf) |
| 215 | { |
| 216 | char *b; |
| 217 | int i; |
| 218 | |
| 219 | s->in_fd = -1; |
| 220 | b = buf + s->out_pos_lo; |
| 221 | /* Copy as much of the error message as possible. |
| 222 | * EXCLUDING the terminating \0. */ |
| 223 | for (i = 0; i < errlen && i < s->out_width; i++) |
| 224 | b[i] = errmsg[i]; |
| 225 | /* Any remaining positions: */ |
| 226 | memset(b + i, '_', s->out_width - i); |
| 227 | } |
| 228 | |
| 229 | enum read_status |
| 230 | slot_read(Slot *s, char *buf) |
| 231 | { |
| 232 | char c; /* Character read. */ |
| 233 | int r; /* Remaining unused positions in buffer range. */ |
| 234 | |
| 235 | for (;;) { |
| 236 | switch (read(s->in_fd, &c, 1)) { |
| 237 | case -1: |
| 238 | khlib_error( |
| 239 | "Failed to read: \"%s\". errno: %d, msg: %s\n", |
| 240 | s->in_fifo, |
| 241 | errno, |
| 242 | strerror(errno) |
| 243 | ); |
| 244 | switch (errno) { |
| 245 | case EINTR: |
| 246 | case EAGAIN: |
| 247 | return RETRY; |
| 248 | default: |
| 249 | return FAILURE; |
| 250 | } |
| 251 | case 0: |
| 252 | khlib_debug("%s: End of FILE\n", s->in_fifo); |
| 253 | s->out_pos_cur = s->out_pos_lo; |
| 254 | return END_OF_FILE; |
| 255 | case 1: |
| 256 | /* TODO: Consider making msg term char a CLI option */ |
| 257 | if (c == '\n' || c == '\0') { |
| 258 | r = (s->out_pos_hi - s->out_pos_cur) + 1; |
| 259 | if (r > 0) |
| 260 | memset(buf + s->out_pos_cur, ' ', r); |
| 261 | return END_OF_MESSAGE; |
| 262 | } else { |
| 263 | if (s->out_pos_cur <= s->out_pos_hi) |
| 264 | buf[s->out_pos_cur++] = c; |
| 265 | else |
| 266 | /* |
| 267 | * Force EOM beyond available range. |
| 268 | * To ensure that a rogue large message |
| 269 | * doesn't trap us here needlessly |
| 270 | * long. |
| 271 | */ |
| 272 | return END_OF_MESSAGE; |
| 273 | } |
| 274 | break; |
| 275 | default: |
| 276 | assert(0); |
| 277 | } |
| 278 | } |
| 279 | } |
| 280 | |
| 281 | void |
| 282 | slots_read(Config *cfg, struct timespec *ti, char *buf) |
| 283 | { |
| 284 | fd_set fds; |
| 285 | int maxfd = -1; |
| 286 | int ready = 0; |
| 287 | struct stat st; |
| 288 | struct timespec t; |
| 289 | Slot *s; |
| 290 | |
| 291 | FD_ZERO(&fds); |
| 292 | for (s = cfg->slots; s; s = s->next) { |
| 293 | /* TODO: Create the FIFO if it doesn't already exist. */ |
| 294 | if (lstat(s->in_fifo, &st) < 0) { |
| 295 | khlib_error( |
| 296 | "Cannot stat \"%s\". Error: %s\n", |
| 297 | s->in_fifo, |
| 298 | strerror(errno) |
| 299 | ); |
| 300 | slot_set_error(s, buf); |
| 301 | continue; |
| 302 | } |
| 303 | if (!(st.st_mode & S_IFIFO)) { |
| 304 | khlib_error("\"%s\" is not a FIFO\n", s->in_fifo); |
| 305 | slot_set_error(s, buf); |
| 306 | continue; |
| 307 | } |
| 308 | if (s->in_fd < 0) { |
| 309 | khlib_debug( |
| 310 | "%s: closed. opening. in_fd: %d\n", |
| 311 | s->in_fifo, |
| 312 | s->in_fd |
| 313 | ); |
| 314 | s->in_fd = open(s->in_fifo, O_RDONLY | O_NONBLOCK); |
| 315 | } else { |
| 316 | khlib_debug( |
| 317 | "%s: already openned. in_fd: %d\n", |
| 318 | s->in_fifo, |
| 319 | s->in_fd |
| 320 | ); |
| 321 | } |
| 322 | if (s->in_fd == -1) { |
| 323 | /* TODO Consider backing off retries for failed slots */ |
| 324 | khlib_error("Failed to open \"%s\"\n", s->in_fifo); |
| 325 | slot_set_error(s, buf); |
| 326 | continue; |
| 327 | } |
| 328 | khlib_debug("%s: open. in_fd: %d\n", s->in_fifo, s->in_fd); |
| 329 | if (s->in_fd > maxfd) |
| 330 | maxfd = s->in_fd; |
| 331 | FD_SET(s->in_fd, &fds); |
| 332 | } |
| 333 | khlib_debug("selecting...\n"); |
| 334 | ready = pselect(maxfd + 1, &fds, NULL, NULL, ti, NULL); |
| 335 | khlib_debug("ready: %d\n", ready); |
| 336 | clock_gettime(CLOCK_MONOTONIC, &t); |
| 337 | if (ready == -1) { |
| 338 | switch (errno) { |
| 339 | case EINTR: |
| 340 | khlib_error( |
| 341 | "pselect interrupted: %d, errno: %d, msg: %s\n", |
| 342 | ready, |
| 343 | errno, |
| 344 | strerror(errno) |
| 345 | ); |
| 346 | /* TODO: Reconsider what to do here. */ |
| 347 | return; |
| 348 | default: |
| 349 | khlib_fatal( |
| 350 | "pselect failed: %d, errno: %d, msg: %s\n", |
| 351 | ready, |
| 352 | errno, |
| 353 | strerror(errno) |
| 354 | ); |
| 355 | } |
| 356 | } |
| 357 | /* At-least-once ensures that expiries are still checked on timeouts. */ |
| 358 | do { |
| 359 | for (s = cfg->slots; s; s = s->next) { |
| 360 | if (s->in_fd < 0) |
| 361 | continue; |
| 362 | if (FD_ISSET(s->in_fd, &fds)) { |
| 363 | khlib_debug("reading: %s\n", s->in_fifo); |
| 364 | switch (slot_read(s, buf)) { |
| 365 | /* |
| 366 | * ### MESSAGE LOSS ### |
| 367 | * is introduced by closing at EOM in addition |
| 368 | * to EOF, since there may be unread messages |
| 369 | * remaining in the pipe. However, |
| 370 | * |
| 371 | * ### INTER-MESSAGE PUSHBACK ### |
| 372 | * is also gained, since pipes block at the |
| 373 | * "open" call. |
| 374 | * |
| 375 | * This is an acceptable trade-off because we |
| 376 | * are a stateless reporter of a _most-recent_ |
| 377 | * status, not a stateful accumulator. |
| 378 | * |
| 379 | * ### LOSSLESS ALTERNATIVES ### |
| 380 | * - Read each pipe until EOF before reading |
| 381 | * another. |
| 382 | * PROBLEM: a fast writer can trap us in the |
| 383 | * read loop. |
| 384 | * |
| 385 | * - Read each pipe until EOM, but close only |
| 386 | * at EOF. |
| 387 | * PROBLEM: a fast writer can fill the pipe |
| 388 | * faster than we can read it and we end-up |
| 389 | * displaying stale data. |
| 390 | * |
| 391 | */ |
| 392 | case END_OF_MESSAGE: |
| 393 | case END_OF_FILE: |
| 394 | case FAILURE: |
| 395 | slot_close(s); |
| 396 | s->in_last_read = t; |
| 397 | ready--; |
| 398 | break; |
| 399 | case RETRY: |
| 400 | break; |
| 401 | default: |
| 402 | assert(0); |
| 403 | } |
| 404 | } else { |
| 405 | slot_expire(s, t, cfg->expiry_character, buf); |
| 406 | } |
| 407 | } |
| 408 | } while (ready); |
| 409 | assert(ready == 0); |
| 410 | } |
| 411 | |
| 412 | void |
| 413 | config_log(Config *cfg) |
| 414 | { |
| 415 | khlib_info( |
| 416 | "Config " |
| 417 | "{" |
| 418 | " interval = %f," |
| 419 | " separator = %s," |
| 420 | " slot_count = %d," |
| 421 | " buf_width = %d," |
| 422 | " slots = ..." |
| 423 | " }\n", |
| 424 | cfg->interval, |
| 425 | cfg->separator, |
| 426 | cfg->slot_count, |
| 427 | cfg->buf_width |
| 428 | ); |
| 429 | slots_log(cfg->slots); |
| 430 | } |
| 431 | |
| 432 | void |
| 433 | config_stretch_for_separators(Config *cfg) |
| 434 | { |
| 435 | int seplen = strlen(cfg->separator); |
| 436 | int prefix = 0; |
| 437 | int nslots = 0; |
| 438 | Slot *s = cfg->slots; |
| 439 | |
| 440 | while (s) { |
| 441 | s->out_pos_lo += prefix; |
| 442 | s->out_pos_hi += prefix; |
| 443 | s->out_pos_cur = s->out_pos_lo; |
| 444 | prefix += seplen; |
| 445 | nslots++; |
| 446 | s = s->next; |
| 447 | } |
| 448 | cfg->buf_width += (seplen * (nslots - 1)); |
| 449 | } |
| 450 | |
| 451 | int |
| 452 | is_pos_num(char *str) |
| 453 | { |
| 454 | while (*str != '\0') |
| 455 | if (!isdigit(*(str++))) |
| 456 | return 0; |
| 457 | return 1; |
| 458 | } |
| 459 | |
| 460 | int |
| 461 | is_decimal(char *str) |
| 462 | { |
| 463 | char c; |
| 464 | int seen = 0; |
| 465 | |
| 466 | while ((c = *(str++)) != '\0') |
| 467 | if (!isdigit(c)) { |
| 468 | if (c == '.' && !seen++) |
| 469 | continue; |
| 470 | else |
| 471 | return 0; |
| 472 | } |
| 473 | return 1; |
| 474 | } |
| 475 | |
| 476 | void |
| 477 | print_usage() |
| 478 | { |
| 479 | assert(argv0); |
| 480 | fprintf( |
| 481 | stderr, |
| 482 | "\n" |
| 483 | "Usage: %s [OPTION ...] SPEC [SPEC ...]\n" |
| 484 | "\n" |
| 485 | " SPEC = FILE_PATH DATA_WIDTH DATA_TTL\n" |
| 486 | " FILE_PATH = string\n" |
| 487 | " DATA_WIDTH = int (* (positive) number of characters *)\n" |
| 488 | " DATA_TTL = float (* (positive) number of seconds *)\n" |
| 489 | " OPTION = -i INTERVAL\n" |
| 490 | " | -s SEPARATOR\n" |
| 491 | " | -x (* Output to X root window *)\n" |
| 492 | " | -l LOG_LEVEL\n" |
| 493 | " | -e EXPIRY_CHARACTER\n" |
| 494 | " SEPARATOR = string\n" |
| 495 | " INTERVAL = float (* (positive) number of seconds *)\n" |
| 496 | " LOG_LEVEL = int (* %d through %d *)\n" |
| 497 | " EXPIRY_CHARACTER = string " |
| 498 | "(* Character with which to fill the slot upon expiration. *)\n" |
| 499 | "\n", |
| 500 | argv0, |
| 501 | Nothing, |
| 502 | Debug |
| 503 | ); |
| 504 | fprintf( |
| 505 | stderr, |
| 506 | "Example: %s -i 1 /dev/shm/khatus/khatus_sensor_x 4 10\n" |
| 507 | "\n", |
| 508 | argv0 |
| 509 | ); |
| 510 | } |
| 511 | |
| 512 | /* For mutually-recursive calls. */ |
| 513 | void opts_parse_any(Config *, int, char *[], int); |
| 514 | |
| 515 | void |
| 516 | parse_opts_opt_i(Config *cfg, int argc, char *argv[], int i) |
| 517 | { |
| 518 | char *param; |
| 519 | |
| 520 | if (i >= argc) |
| 521 | usage("Option -i parameter is missing.\n"); |
| 522 | param = argv[i++]; |
| 523 | if (!is_decimal(param)) |
| 524 | usage("Option -i parameter is invalid: \"%s\"\n", param); |
| 525 | cfg->interval = atof(param); |
| 526 | opts_parse_any(cfg, argc, argv, i); |
| 527 | } |
| 528 | |
| 529 | void |
| 530 | parse_opts_opt_s(Config *cfg, int argc, char *argv[], int i) |
| 531 | { |
| 532 | if (i >= argc) |
| 533 | usage("Option -s parameter is missing.\n"); |
| 534 | cfg->separator = calloc((strlen(argv[i]) + 1), sizeof(char)); |
| 535 | strcpy(cfg->separator, argv[i]); |
| 536 | opts_parse_any(cfg, argc, argv, ++i); |
| 537 | } |
| 538 | |
| 539 | void |
| 540 | parse_opts_opt_l(Config *cfg, int argc, char *argv[], int i) |
| 541 | { |
| 542 | char *param; |
| 543 | int log_level; |
| 544 | |
| 545 | if (i >= argc) |
| 546 | usage("Option -l parameter is missing.\n"); |
| 547 | param = argv[i++]; |
| 548 | if (!is_pos_num(param)) |
| 549 | usage("Option -l parameter is invalid: \"%s\"\n", param); |
| 550 | log_level = atoi(param); |
| 551 | if (log_level > Debug) |
| 552 | usage( |
| 553 | "Option -l value (%d) exceeds maximum (%d)\n", |
| 554 | log_level, |
| 555 | Debug |
| 556 | ); |
| 557 | _khlib_log_level = log_level; |
| 558 | opts_parse_any(cfg, argc, argv, i); |
| 559 | } |
| 560 | |
| 561 | void |
| 562 | parse_opts_opt_e(Config *cfg, int argc, char *argv[], int i) |
| 563 | { |
| 564 | if (i >= argc) |
| 565 | usage("Option -e parameter is missing.\n"); |
| 566 | cfg->expiry_character = argv[i++][0]; |
| 567 | opts_parse_any(cfg, argc, argv, i); |
| 568 | } |
| 569 | |
| 570 | void |
| 571 | parse_opts_opt(Config *cfg, int argc, char *argv[], int i) |
| 572 | { |
| 573 | switch (argv[i][1]) { |
| 574 | case 'i': |
| 575 | /* TODO: Generic set_int */ |
| 576 | parse_opts_opt_i(cfg, argc, argv, ++i); |
| 577 | break; |
| 578 | case 's': |
| 579 | /* TODO: Generic set_str */ |
| 580 | parse_opts_opt_s(cfg, argc, argv, ++i); |
| 581 | break; |
| 582 | case 'x': |
| 583 | cfg->to_x_root = 1; |
| 584 | opts_parse_any(cfg, argc, argv, ++i); |
| 585 | break; |
| 586 | case 'l': |
| 587 | /* TODO: Generic set_int */ |
| 588 | parse_opts_opt_l(cfg, argc, argv, ++i); |
| 589 | break; |
| 590 | case 'e': |
| 591 | /* TODO: Generic set_str */ |
| 592 | parse_opts_opt_e(cfg, argc, argv, ++i); |
| 593 | break; |
| 594 | default : |
| 595 | usage("Option \"%s\" is invalid\n", argv[i]); |
| 596 | } |
| 597 | } |
| 598 | |
| 599 | void |
| 600 | parse_opts_spec(Config *cfg, int argc, char *argv[], int i) |
| 601 | { |
| 602 | char *n; |
| 603 | char *w; |
| 604 | char *t; |
| 605 | struct timespec in_last_read; |
| 606 | Slot *s; |
| 607 | |
| 608 | if ((i + 3) > argc) |
| 609 | usage( |
| 610 | "[spec] Parameter(s) missing for fifo \"%s\".\n", |
| 611 | argv[i] |
| 612 | ); |
| 613 | |
| 614 | n = argv[i++]; |
| 615 | w = argv[i++]; |
| 616 | t = argv[i++]; |
| 617 | |
| 618 | if (!is_pos_num(w)) |
| 619 | usage("[spec] Invalid width: \"%s\", for fifo \"%s\"\n", w, n); |
| 620 | if (!is_decimal(t)) |
| 621 | usage("[spec] Invalid TTL: \"%s\", for fifo \"%s\"\n", t, n); |
| 622 | |
| 623 | in_last_read.tv_sec = 0; |
| 624 | in_last_read.tv_nsec = 0; |
| 625 | s = calloc(1, sizeof(struct Slot)); |
| 626 | |
| 627 | if (s) { |
| 628 | s->in_fifo = n; |
| 629 | s->in_fd = -1; |
| 630 | s->out_width = atoi(w); |
| 631 | s->out_ttl = khlib_timespec_of_float(atof(t)); |
| 632 | s->in_last_read = in_last_read; |
| 633 | s->out_pos_lo = cfg->buf_width; |
| 634 | s->out_pos_cur = s->out_pos_lo; |
| 635 | s->out_pos_hi = s->out_pos_lo + s->out_width - 1; |
| 636 | s->next = cfg->slots; |
| 637 | |
| 638 | cfg->slots = s; |
| 639 | cfg->buf_width += s->out_width; |
| 640 | cfg->slot_count++; |
| 641 | } else { |
| 642 | khlib_fatal("[memory] Allocation failure."); |
| 643 | } |
| 644 | opts_parse_any(cfg, argc, argv, i); |
| 645 | } |
| 646 | |
| 647 | void |
| 648 | opts_parse_any(Config *cfg, int argc, char *argv[], int i) |
| 649 | { |
| 650 | if (i < argc) { |
| 651 | switch (argv[i][0]) { |
| 652 | case '-': |
| 653 | parse_opts_opt(cfg, argc, argv, i); |
| 654 | break; |
| 655 | default : |
| 656 | parse_opts_spec(cfg, argc, argv, i); |
| 657 | } |
| 658 | } |
| 659 | } |
| 660 | |
| 661 | void |
| 662 | opts_parse(Config *cfg, int argc, char *argv[]) |
| 663 | { |
| 664 | opts_parse_any(cfg, argc, argv, 1); |
| 665 | cfg->slots = slots_rev(cfg->slots); |
| 666 | config_log(cfg); |
| 667 | if (cfg->slots == NULL) |
| 668 | usage("No slot specs were given!\n"); |
| 669 | } |
| 670 | |
| 671 | void |
| 672 | loop(Config *cfg, char *buf, Display *d) |
| 673 | { |
| 674 | struct timespec |
| 675 | t0, /* time stamp. before reading slots */ |
| 676 | t1, /* time stamp. after reading slots */ |
| 677 | ti, /* time interval desired (t1 - t0) */ |
| 678 | td, /* time interval measured (t1 - t0) */ |
| 679 | tc; /* time interval correction (ti - td) when td < ti */ |
| 680 | |
| 681 | ti = khlib_timespec_of_float(cfg->interval); |
| 682 | while (running) { |
| 683 | clock_gettime(CLOCK_MONOTONIC, &t0); // FIXME: check errors |
| 684 | slots_read(cfg, &ti, buf); |
| 685 | if (cfg->to_x_root) { |
| 686 | if (XStoreName(d, DefaultRootWindow(d), buf) < 0) |
| 687 | khlib_fatal("XStoreName failed.\n"); |
| 688 | XFlush(d); |
| 689 | } else { |
| 690 | puts(buf); |
| 691 | fflush(stdout); |
| 692 | } |
| 693 | clock_gettime(CLOCK_MONOTONIC, &t1); // FIXME: check errors |
| 694 | timespecsub(&t1, &t0, &td); |
| 695 | khlib_debug( |
| 696 | "td {tv_sec = %ld, tv_nsec = %ld}\n", |
| 697 | td.tv_sec, |
| 698 | td.tv_nsec |
| 699 | ); |
| 700 | if (timespeccmp(&td, &ti, <)) { |
| 701 | /* |
| 702 | * Pushback on data producers by refusing to read the |
| 703 | * pipe more frequently than the interval. |
| 704 | */ |
| 705 | timespecsub(&ti, &td, &tc); |
| 706 | khlib_sleep(&tc); |
| 707 | } |
| 708 | } |
| 709 | } |
| 710 | |
| 711 | void |
| 712 | terminate(int s) |
| 713 | { |
| 714 | khlib_debug("terminating due to signal %d\n", s); |
| 715 | running = 0; |
| 716 | } |
| 717 | |
| 718 | int |
| 719 | main(int argc, char *argv[]) |
| 720 | { |
| 721 | argv0 = argv[0]; |
| 722 | |
| 723 | Config cfg = { |
| 724 | .interval = 1.0, |
| 725 | .separator = "|", |
| 726 | .expiry_character = '_', |
| 727 | .slots = NULL, |
| 728 | .slot_count = 0, |
| 729 | .buf_width = 0, |
| 730 | .to_x_root = 0, |
| 731 | }; |
| 732 | char *buf; |
| 733 | Display *d = NULL; |
| 734 | struct sigaction sa; |
| 735 | |
| 736 | memset(&sa, 0, sizeof(sa)); |
| 737 | sa.sa_handler = terminate; |
| 738 | sigaction(SIGTERM, &sa, NULL); |
| 739 | sigaction(SIGINT , &sa, NULL); |
| 740 | |
| 741 | opts_parse(&cfg, argc, argv); |
| 742 | slots_assert_fifos_exist(cfg.slots); |
| 743 | config_stretch_for_separators(&cfg); |
| 744 | buf = buf_create(&cfg); |
| 745 | if (cfg.to_x_root && !(d = XOpenDisplay(NULL))) |
| 746 | khlib_fatal("XOpenDisplay failed with: %p\n", d); |
| 747 | loop(&cfg, buf, d); |
| 748 | slots_close(cfg.slots); |
| 749 | return EXIT_SUCCESS; |
| 750 | } |