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envstat.c revision 1.61
      1 /* $NetBSD: envstat.c,v 1.61 2008/04/26 02:56:57 xtraeme Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2007, 2008 Juan Romero Pardines.
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     26  */
     27 
     28 #include <sys/cdefs.h>
     29 #ifndef lint
     30 __RCSID("$NetBSD: envstat.c,v 1.61 2008/04/26 02:56:57 xtraeme Exp $");
     31 #endif /* not lint */
     32 
     33 #include <stdio.h>
     34 #include <stdlib.h>
     35 #include <stdbool.h>
     36 #include <string.h>
     37 #include <unistd.h>
     38 #include <fcntl.h>
     39 #include <err.h>
     40 #include <errno.h>
     41 #include <syslog.h>
     42 #include <sys/envsys.h>
     43 #include <sys/types.h>
     44 #include <sys/queue.h>
     45 #include <prop/proplib.h>
     46 
     47 #include "envstat.h"
     48 
     49 #define _PATH_DEV_SYSMON	"/dev/sysmon"
     50 
     51 #define ENVSYS_DFLAG	0x00000001	/* list registered devices */
     52 #define ENVSYS_FFLAG	0x00000002	/* show temp in farenheit */
     53 #define ENVSYS_LFLAG	0x00000004	/* list sensors */
     54 #define ENVSYS_XFLAG	0x00000008	/* externalize dictionary */
     55 #define ENVSYS_IFLAG 	0x00000010	/* skip invalid sensors */
     56 #define ENVSYS_SFLAG	0x00000020	/* remove all properties set */
     57 #define ENVSYS_TFLAG	0x00000040	/* make statistics */
     58 
     59 /* Sensors */
     60 typedef struct envsys_sensor {
     61 	SIMPLEQ_ENTRY(envsys_sensor) entries;
     62 	int32_t	cur_value;
     63 	int32_t	max_value;
     64 	int32_t	min_value;
     65 	int32_t	avg_value;
     66 	int32_t critcap_value;
     67 	int32_t	critmin_value;
     68 	int32_t	critmax_value;
     69 	char	desc[ENVSYS_DESCLEN];
     70 	char	type[ENVSYS_DESCLEN];
     71 	char	drvstate[ENVSYS_DESCLEN];
     72 	char	battcap[ENVSYS_DESCLEN];
     73 	char 	dvname[ENVSYS_DESCLEN];
     74 	bool	invalid;
     75 	bool	visible;
     76 	bool	percentage;
     77 } *sensor_t;
     78 
     79 /* Sensor statistics */
     80 typedef struct envsys_sensor_stats {
     81 	SIMPLEQ_ENTRY(envsys_sensor_stats) entries;
     82 	int32_t	max;
     83 	int32_t	min;
     84 	int32_t avg;
     85 	char	desc[ENVSYS_DESCLEN];
     86 	bool	queued;
     87 } *sensor_stats_t;
     88 
     89 /* Device properties */
     90 typedef struct envsys_dvprops {
     91 	uint64_t	refresh_timo;
     92 	/* more members could be added in the future */
     93 } *dvprops_t;
     94 
     95 /* A simple queue to manage all sensors */
     96 static SIMPLEQ_HEAD(, envsys_sensor) sensors_list =
     97     SIMPLEQ_HEAD_INITIALIZER(sensors_list);
     98 
     99 /* A simple queue to manage statistics for all sensors */
    100 static SIMPLEQ_HEAD(, envsys_sensor_stats) sensor_stats_list =
    101     SIMPLEQ_HEAD_INITIALIZER(sensor_stats_list);
    102 
    103 static unsigned int 	interval, flags, width;
    104 static char 		*mydevname, *sensors;
    105 static bool 		statistics;
    106 static u_int		header_passes;
    107 
    108 static int 		parse_dictionary(int);
    109 static int 		send_dictionary(FILE *, int);
    110 static int 		find_sensors(prop_array_t, const char *, dvprops_t);
    111 static void 		print_sensors(void);
    112 static int 		check_sensors(char *);
    113 static int 		usage(void);
    114 
    115 
    116 int main(int argc, char **argv)
    117 {
    118 	prop_dictionary_t dict;
    119 	int c, fd, rval = 0;
    120 	char *endptr, *configfile = NULL;
    121 	FILE *cf;
    122 
    123 	setprogname(argv[0]);
    124 
    125 	while ((c = getopt(argc, argv, "c:Dd:fIi:lrSs:Tw:x")) != -1) {
    126 		switch (c) {
    127 		case 'c':	/* configuration file */
    128 			configfile = strdup(optarg);
    129 			if (configfile == NULL)
    130 				err(EXIT_FAILURE, "strdup");
    131 			break;
    132 		case 'D':	/* list registered devices */
    133 			flags |= ENVSYS_DFLAG;
    134 			break;
    135 		case 'd':	/* show sensors of a specific device */
    136 			mydevname = strdup(optarg);
    137 			if (mydevname == NULL)
    138 				err(EXIT_FAILURE, "strdup");
    139 			break;
    140 		case 'f':	/* display temperature in Farenheit */
    141 			flags |= ENVSYS_FFLAG;
    142 			break;
    143 		case 'I':	/* Skips invalid sensors */
    144 			flags |= ENVSYS_IFLAG;
    145 			break;
    146 		case 'i':	/* wait time between intervals */
    147 			interval = (unsigned int)strtoul(optarg, &endptr, 10);
    148 			if (*endptr != '\0')
    149 				errx(EXIT_FAILURE, "bad interval '%s'", optarg);
    150 			break;
    151 		case 'l':	/* list sensors */
    152 			flags |= ENVSYS_LFLAG;
    153 			break;
    154 		case 'r':
    155 			/*
    156 			 * This flag is noop.. it's only here for
    157 			 * compatibility with the old implementation.
    158 			 */
    159 			break;
    160 		case 'S':
    161 			flags |= ENVSYS_SFLAG;
    162 			break;
    163 		case 's':	/* only show specified sensors */
    164 			sensors = strdup(optarg);
    165 			if (sensors == NULL)
    166 				err(EXIT_FAILURE, "strdup");
    167 			break;
    168 		case 'T':	/* make statistics */
    169 			flags |= ENVSYS_TFLAG;
    170 			break;
    171 		case 'w':	/* width value for the lines */
    172 			width = (unsigned int)strtoul(optarg, &endptr, 10);
    173 			if (*endptr != '\0')
    174 				errx(EXIT_FAILURE, "bad width '%s'", optarg);
    175 			break;
    176 		case 'x':	/* print the dictionary in raw format */
    177 			flags |= ENVSYS_XFLAG;
    178 			break;
    179 		case '?':
    180 		default:
    181 			usage();
    182 			/* NOTREACHED */
    183 		}
    184 	}
    185 
    186 	argc -= optind;
    187 	argv += optind;
    188 
    189 	if (argc > 0)
    190 		usage();
    191 
    192 	/* Check if we want to make statistics */
    193 	if (flags & ENVSYS_TFLAG) {
    194 		if (!interval)
    195 			errx(EXIT_FAILURE,
    196 		    	    "-T cannot be used without an interval (-i)");
    197 		else
    198 			statistics = true;
    199 	}
    200 
    201 	if (mydevname && sensors)
    202 		errx(EXIT_FAILURE, "-d flag cannot be used with -s");
    203 
    204 	/* Open the device in ro mode */
    205 	if ((fd = open(_PATH_DEV_SYSMON, O_RDONLY)) == -1)
    206 		err(EXIT_FAILURE, "%s", _PATH_DEV_SYSMON);
    207 
    208 	/* Print dictionary in raw mode */
    209 	if (flags & ENVSYS_XFLAG) {
    210 		rval = prop_dictionary_recv_ioctl(fd,
    211 						  ENVSYS_GETDICTIONARY,
    212 						  &dict);
    213 		if (rval)
    214 			errx(EXIT_FAILURE, "%s", strerror(rval));
    215 
    216 		config_dict_dump(dict);
    217 
    218 	/* Remove all properties set in dictionary */
    219 	} else if (flags & ENVSYS_SFLAG) {
    220 		/* Close the ro descriptor */
    221 		(void)close(fd);
    222 
    223 		/* open the fd in rw mode */
    224 		if ((fd = open(_PATH_DEV_SYSMON, O_RDWR)) == -1)
    225 			err(EXIT_FAILURE, "%s", _PATH_DEV_SYSMON);
    226 
    227 		dict = prop_dictionary_create();
    228 		if (!dict)
    229 			err(EXIT_FAILURE, "prop_dictionary_create");
    230 
    231 		rval = prop_dictionary_set_bool(dict,
    232 						"envsys-remove-props",
    233 					        true);
    234 		if (!rval)
    235 			err(EXIT_FAILURE, "prop_dict_set_bool");
    236 
    237 		/* send the dictionary to the kernel now */
    238 		rval = prop_dictionary_send_ioctl(dict, fd, ENVSYS_REMOVEPROPS);
    239 		if (rval)
    240 			warnx("%s", strerror(rval));
    241 
    242 	/* Set properties in dictionary */
    243 	} else if (configfile) {
    244 		/*
    245 		 * Parse the configuration file.
    246 		 */
    247 		if ((cf = fopen(configfile, "r")) == NULL) {
    248 			syslog(LOG_ERR, "fopen failed: %s", strerror(errno));
    249 			errx(EXIT_FAILURE, "%s", strerror(errno));
    250 		}
    251 
    252 		rval = send_dictionary(cf, fd);
    253 		(void)fclose(cf);
    254 
    255 	/* Show sensors with interval */
    256 	} else if (interval) {
    257 		for (;;) {
    258 			rval = parse_dictionary(fd);
    259 			if (rval)
    260 				break;
    261 
    262 			(void)fflush(stdout);
    263 			(void)sleep(interval);
    264 		}
    265 	/* Show sensors without interval */
    266 	} else {
    267 		rval = parse_dictionary(fd);
    268 	}
    269 
    270 	if (sensors)
    271 		free(sensors);
    272 	if (mydevname)
    273 		free(mydevname);
    274 	(void)close(fd);
    275 
    276 	return rval ? EXIT_FAILURE : EXIT_SUCCESS;
    277 }
    278 
    279 static int
    280 send_dictionary(FILE *cf, int fd)
    281 {
    282 	prop_dictionary_t kdict, udict;
    283 	int error = 0;
    284 
    285 	/* Retrieve dictionary from kernel */
    286 	error = prop_dictionary_recv_ioctl(fd, ENVSYS_GETDICTIONARY, &kdict);
    287       	if (error)
    288 		return error;
    289 
    290 	config_parse(cf, kdict);
    291 
    292 	/*
    293 	 * Dictionary built by the parser from the configuration file.
    294 	 */
    295 	udict = config_dict_parsed();
    296 
    297 	/*
    298 	 * Close the read only descriptor and open a new one read write.
    299 	 */
    300 	(void)close(fd);
    301 	if ((fd = open(_PATH_DEV_SYSMON, O_RDWR)) == -1) {
    302 		error = errno;
    303 		warn("%s", _PATH_DEV_SYSMON);
    304 		return error;
    305 	}
    306 
    307 	/*
    308 	 * Send our sensor properties dictionary to the kernel then.
    309 	 */
    310 	error = prop_dictionary_send_ioctl(udict, fd, ENVSYS_SETDICTIONARY);
    311 	if (error)
    312 		warnx("%s", strerror(error));
    313 
    314 	prop_object_release(udict);
    315 	return error;
    316 }
    317 
    318 static sensor_stats_t
    319 find_stats_sensor(const char *desc)
    320 {
    321 	sensor_stats_t stats = NULL;
    322 	bool found = false;
    323 
    324 	/*
    325 	 * If we matched a sensor by its description return it, otherwise
    326 	 * allocate a new one.
    327 	 */
    328 	SIMPLEQ_FOREACH(stats, &sensor_stats_list, entries) {
    329 		if (strcmp(stats->desc, desc) == 0) {
    330 			found = true;
    331 			break;
    332 		}
    333 	}
    334 
    335 	if (found == false) {
    336 		/*
    337 		 * don't bother with return value, the caller will check
    338 		 * if it's NULL or not.
    339 		 */
    340 		stats = calloc(1, sizeof(*stats));
    341 	}
    342 
    343 	return stats;
    344 }
    345 
    346 static int
    347 parse_dictionary(int fd)
    348 {
    349 	sensor_t sensor = NULL;
    350 	dvprops_t edp = NULL;
    351 	prop_array_t array;
    352 	prop_dictionary_t dict;
    353 	prop_object_iterator_t iter;
    354 	prop_object_t obj;
    355 	const char *dnp = NULL;
    356 	int rval = 0;
    357 
    358 	/* receive dictionary from kernel */
    359 	rval = prop_dictionary_recv_ioctl(fd, ENVSYS_GETDICTIONARY, &dict);
    360 	if (rval)
    361 		return rval;
    362 
    363 	/* No drivers registered? */
    364 	if (prop_dictionary_count(dict) == 0) {
    365 		warnx("no drivers registered");
    366 		goto out;
    367 	}
    368 
    369 	if (mydevname) {
    370 		/* -d flag specified, print sensors only for this device */
    371 		obj = prop_dictionary_get(dict, mydevname);
    372 		if (prop_object_type(obj) != PROP_TYPE_ARRAY) {
    373 			warnx("unknown device `%s'", mydevname);
    374 			rval = EINVAL;
    375 			goto out;
    376 		}
    377 
    378 		rval = find_sensors(obj, mydevname, NULL);
    379 		if (rval)
    380 			goto out;
    381 
    382 	} else {
    383 		/* print sensors for all devices registered */
    384 		iter = prop_dictionary_iterator(dict);
    385 		if (iter == NULL) {
    386 			rval = EINVAL;
    387 			goto out;
    388 		}
    389 
    390 		/* iterate over the dictionary returned by the kernel */
    391 		while ((obj = prop_object_iterator_next(iter)) != NULL) {
    392 			array = prop_dictionary_get_keysym(dict, obj);
    393 			if (prop_object_type(array) != PROP_TYPE_ARRAY) {
    394 				warnx("no sensors found");
    395 				rval = EINVAL;
    396 				goto out;
    397 			}
    398 
    399 			edp = calloc(1, sizeof(*edp));
    400 			if (!edp) {
    401 				rval = ENOMEM;
    402 				goto out;
    403 			}
    404 
    405 			dnp = prop_dictionary_keysym_cstring_nocopy(obj);
    406 			rval = find_sensors(array, dnp, edp);
    407 			if (rval)
    408 				goto out;
    409 
    410 			if (((flags & ENVSYS_LFLAG) == 0) &&
    411 			    (flags & ENVSYS_DFLAG)) {
    412 				(void)printf("%s (checking events every ",
    413 				    dnp);
    414 				if (edp->refresh_timo == 1)
    415 					(void)printf("second)\n");
    416 				else
    417 					(void)printf("%d seconds)\n",
    418 					    (int)edp->refresh_timo);
    419 			}
    420 
    421 			free(edp);
    422 			edp = NULL;
    423 		}
    424 		prop_object_iterator_release(iter);
    425 	}
    426 
    427 	/* print sensors now */
    428 	if (sensors) {
    429 		char *str = strdup(sensors);
    430 		if (!str) {
    431 			rval = ENOMEM;
    432 			goto out;
    433 		}
    434 		rval = check_sensors(str);
    435 		if (rval) {
    436 			free(str);
    437 			goto out;
    438 		}
    439 		free(str);
    440 	}
    441 	if ((flags & ENVSYS_LFLAG) == 0 && (flags & ENVSYS_DFLAG) == 0)
    442 		print_sensors();
    443 	if (interval)
    444 		(void)printf("\n");
    445 
    446 out:
    447 	while ((sensor = SIMPLEQ_FIRST(&sensors_list))) {
    448 		SIMPLEQ_REMOVE_HEAD(&sensors_list, entries);
    449 		free(sensor);
    450 	}
    451 	if (edp)
    452 		free(edp);
    453 	prop_object_release(dict);
    454 	return rval;
    455 }
    456 
    457 static int
    458 find_sensors(prop_array_t array, const char *dvname, dvprops_t edp)
    459 {
    460 	prop_object_iterator_t iter;
    461 	prop_object_t obj, obj1, obj2;
    462 	prop_string_t state, desc = NULL;
    463 	sensor_t sensor = NULL;
    464 	sensor_stats_t stats = NULL;
    465 
    466 	iter = prop_array_iterator(array);
    467 	if (!iter)
    468 		return ENOMEM;
    469 
    470 	/* iterate over the array of dictionaries */
    471 	while ((obj = prop_object_iterator_next(iter)) != NULL) {
    472 		/* get the refresh-timeout property */
    473 		obj2 = prop_dictionary_get(obj, "device-properties");
    474 		if (obj2) {
    475 			if (!edp)
    476 				continue;
    477 			if (!prop_dictionary_get_uint64(obj2,
    478 							"refresh-timeout",
    479 							&edp->refresh_timo))
    480 				continue;
    481 		}
    482 
    483 		/* new sensor coming */
    484 		sensor = calloc(1, sizeof(*sensor));
    485 		if (sensor == NULL) {
    486 			prop_object_iterator_release(iter);
    487 			return ENOMEM;
    488 		}
    489 
    490 		/* copy device name */
    491 		(void)strlcpy(sensor->dvname, dvname, sizeof(sensor->dvname));
    492 
    493 		/* description string */
    494 		desc = prop_dictionary_get(obj, "description");
    495 		if (desc) {
    496 			/* copy description */
    497 			(void)strlcpy(sensor->desc,
    498 			    prop_string_cstring_nocopy(desc),
    499 		    	    sizeof(sensor->desc));
    500 		} else {
    501 			free(sensor);
    502 			continue;
    503 		}
    504 
    505 		/* type string */
    506 		obj1  = prop_dictionary_get(obj, "type");
    507 		if (obj1) {
    508 			/* copy type */
    509 			(void)strlcpy(sensor->type,
    510 		    	    prop_string_cstring_nocopy(obj1),
    511 		    	    sizeof(sensor->type));
    512 		} else {
    513 			free(sensor);
    514 			continue;
    515 		}
    516 
    517 		/* check sensor's state */
    518 		state = prop_dictionary_get(obj, "state");
    519 
    520 		/* mark sensors with invalid/unknown state */
    521 		if ((prop_string_equals_cstring(state, "invalid") ||
    522 		     prop_string_equals_cstring(state, "unknown")))
    523 			sensor->invalid = true;
    524 
    525 		/* get current drive state string */
    526 		obj1 = prop_dictionary_get(obj, "drive-state");
    527 		if (obj1) {
    528 			(void)strlcpy(sensor->drvstate,
    529 			    prop_string_cstring_nocopy(obj1),
    530 			    sizeof(sensor->drvstate));
    531 		}
    532 
    533 		/* get current battery capacity string */
    534 		obj1 = prop_dictionary_get(obj, "battery-capacity");
    535 		if (obj1) {
    536 			(void)strlcpy(sensor->battcap,
    537 			    prop_string_cstring_nocopy(obj1),
    538 			    sizeof(sensor->battcap));
    539 		}
    540 
    541 		/* get current value */
    542 		obj1 = prop_dictionary_get(obj, "cur-value");
    543 		if (obj1)
    544 			sensor->cur_value = prop_number_integer_value(obj1);
    545 
    546 		/* get max value */
    547 		obj1 = prop_dictionary_get(obj, "max-value");
    548 		if (obj1)
    549 			sensor->max_value = prop_number_integer_value(obj1);
    550 
    551 		/* get min value */
    552 		obj1 = prop_dictionary_get(obj, "min-value");
    553 		if (obj1)
    554 			sensor->min_value = prop_number_integer_value(obj1);
    555 
    556 		/* get avg value */
    557 		obj1 = prop_dictionary_get(obj, "avg-value");
    558 		if (obj1)
    559 			sensor->avg_value = prop_number_integer_value(obj1);
    560 
    561 		/* get percentage flag */
    562 		obj1 = prop_dictionary_get(obj, "want-percentage");
    563 		if (obj1)
    564 			sensor->percentage = prop_bool_true(obj1);
    565 
    566 		/* get critical max value if available */
    567 		obj1 = prop_dictionary_get(obj, "critical-max");
    568 		if (obj1)
    569 			sensor->critmax_value = prop_number_integer_value(obj1);
    570 
    571 		/* get critical min value if available */
    572 		obj1 = prop_dictionary_get(obj, "critical-min");
    573 		if (obj1)
    574 			sensor->critmin_value = prop_number_integer_value(obj1);
    575 
    576 		/* get critical capacity value if available */
    577 		obj1 = prop_dictionary_get(obj, "critical-capacity");
    578 		if (obj1)
    579 			sensor->critcap_value = prop_number_integer_value(obj1);
    580 
    581 		/* print sensor names if -l was given */
    582 		if (flags & ENVSYS_LFLAG) {
    583 			if (width)
    584 				(void)printf("%*s\n", width,
    585 				    prop_string_cstring_nocopy(desc));
    586 			else
    587 				(void)printf("%s\n",
    588 				    prop_string_cstring_nocopy(desc));
    589 		}
    590 
    591 		/* Add the sensor into the list */
    592 		SIMPLEQ_INSERT_TAIL(&sensors_list, sensor, entries);
    593 
    594 		/* Collect statistics if flag enabled */
    595 		if (statistics) {
    596 			/* ignore invalid data */
    597 			if (!sensor->cur_value)
    598 				continue;
    599 
    600 			/* find or allocate a new statistics sensor */
    601 			stats = find_stats_sensor(sensor->desc);
    602 			if (stats == NULL) {
    603 				free(sensor);
    604 				prop_object_iterator_release(iter);
    605 				return ENOMEM;
    606 			}
    607 
    608 			/* collect data */
    609 			if (!stats->max)
    610 				stats->max = sensor->cur_value;
    611 			if (!stats->min)
    612 				stats->min = sensor->cur_value;
    613 
    614 			if (sensor->cur_value > stats->max)
    615 				stats->max = sensor->cur_value;
    616 
    617 			if (sensor->cur_value < stats->min)
    618 				stats->min = sensor->cur_value;
    619 
    620 			/* compute avg value */
    621 			if (stats->max && stats->min)
    622 				stats->avg =
    623 				    (sensor->cur_value + stats->max +
    624 				    stats->min) / 3;
    625 
    626 			/* add the statistics sensor into the queue */
    627 			if (!stats->queued) {
    628 				(void)strlcpy(stats->desc, sensor->desc,
    629 				    sizeof(stats->desc));
    630 				stats->queued = true;
    631 				SIMPLEQ_INSERT_TAIL(&sensor_stats_list,
    632 				    stats, entries);
    633 			}
    634 		}
    635 	}
    636 
    637 	/* free memory */
    638 	prop_object_iterator_release(iter);
    639 	return 0;
    640 }
    641 
    642 static int
    643 check_sensors(char *str)
    644 {
    645 	sensor_t sensor = NULL;
    646 	char *dvstring, *sstring, *p, *last;
    647 	bool sensor_found = false;
    648 
    649 	/*
    650 	 * Parse device name and sensor description and find out
    651 	 * if the sensor is valid.
    652 	 */
    653 	for ((p = strtok_r(str, ",", &last)); p;
    654 	     (p = strtok_r(NULL, ",", &last))) {
    655 		/* get device name */
    656 		dvstring = strtok(p, ":");
    657 		if (dvstring == NULL) {
    658 			warnx("missing device name");
    659 			return EINVAL;
    660 		}
    661 
    662 		/* get sensor description */
    663 		sstring = strtok(NULL, ":");
    664 		if (sstring == NULL) {
    665 			warnx("missing sensor description");
    666 			return EINVAL;
    667 		}
    668 
    669 		SIMPLEQ_FOREACH(sensor, &sensors_list, entries) {
    670 			/* skip until we match device */
    671 			if (strcmp(dvstring, sensor->dvname))
    672 				continue;
    673 			if (strcmp(sstring, sensor->desc) == 0) {
    674 				sensor->visible = true;
    675 				sensor_found = true;
    676 				break;
    677 			}
    678 		}
    679 		if (sensor_found == false) {
    680 			warnx("unknown sensor `%s' for device `%s'",
    681 		       	    sstring, dvstring);
    682 			return EINVAL;
    683 		}
    684 		sensor_found = false;
    685 	}
    686 
    687 	/* check if all sensors were ok, and error out if not */
    688 	SIMPLEQ_FOREACH(sensor, &sensors_list, entries)
    689 		if (sensor->visible)
    690 			return 0;
    691 
    692 	warnx("no sensors selected to display");
    693 	return EINVAL;
    694 }
    695 
    696 static void
    697 print_sensors(void)
    698 {
    699 	sensor_t sensor;
    700 	sensor_stats_t stats = NULL;
    701 	size_t maxlen = 0, ilen = 32 + 3;
    702 	double temp = 0;
    703 	const char *invalid = "N/A", *degrees, *tmpstr, *stype;
    704 	const char *a, *b, *c, *d, *units;
    705 
    706 	tmpstr = stype = d = NULL;
    707 
    708 	/* find the longest description */
    709 	SIMPLEQ_FOREACH(sensor, &sensors_list, entries)
    710 		if (strlen(sensor->desc) > maxlen)
    711 			maxlen = strlen(sensor->desc);
    712 
    713 	if (width)
    714 		maxlen = width;
    715 
    716 	/*
    717 	 * Print a header at the bottom only once showing different
    718 	 * members if the statistics flag is set or not.
    719 	 *
    720 	 * As bonus if -s is set, only print this header every 10 iterations
    721 	 * to avoid redundancy... like vmstat(1).
    722 	 */
    723 
    724 	a = "Cur";
    725 	units = "Unit";
    726 	if (statistics) {
    727 		b = "Max";
    728 		c = "Min";
    729 		d = "Avg";
    730 	} else {
    731 		b = "CritMax";
    732 		c = "CritMin";
    733 		d = "CritCap";
    734 	}
    735 
    736 	if (!sensors || (!header_passes && sensors) ||
    737 	    (header_passes == 10 && sensors)) {
    738 		(void)printf("%s%*s  %10s %8s %8s %8s %8s\n",
    739 		    mydevname ? "" : "  ", (int)maxlen,
    740 		    "", a, b, c, d, units);
    741 		if (sensors && header_passes == 10)
    742 			header_passes = 0;
    743 	}
    744 	if (sensors)
    745 		header_passes++;
    746 
    747 	/* print the sensors */
    748 	SIMPLEQ_FOREACH(sensor, &sensors_list, entries) {
    749 		/* skip sensors that were not marked as visible */
    750 		if (sensors && !sensor->visible)
    751 			continue;
    752 
    753 		/* skip invalid sensors if -I is set */
    754 		if ((flags & ENVSYS_IFLAG) && sensor->invalid)
    755 			continue;
    756 
    757 		/* print device name */
    758 		if (!mydevname) {
    759 			if (tmpstr == NULL || strcmp(tmpstr, sensor->dvname))
    760 				printf("[%s]\n", sensor->dvname);
    761 
    762 			tmpstr = sensor->dvname;
    763 		}
    764 
    765 		/* print sensor description */
    766 		(void)printf("%s%*.*s", mydevname ? "" : "  ", (int)maxlen,
    767 		    (int)maxlen, sensor->desc);
    768 
    769 		/* print invalid string */
    770 		if (sensor->invalid) {
    771 			(void)printf(": %10s\n", invalid);
    772 			continue;
    773 		}
    774 
    775 		/* find out the statistics sensor */
    776 		if (statistics) {
    777 			stats = find_stats_sensor(sensor->desc);
    778 			if (stats == NULL)
    779 				;
    780 			else if (stats && !stats->queued)
    781 				free(stats);
    782 		}
    783 
    784 		/*
    785 		 * Indicator and Battery charge sensors.
    786 		 */
    787 		if ((strcmp(sensor->type, "Indicator") == 0) ||
    788 		    (strcmp(sensor->type, "Battery charge") == 0)) {
    789 
    790 			(void)printf(": %10s", sensor->cur_value ? "ON" : "OFF");
    791 
    792 /* converts the value to degC or degF */
    793 #define CONVERTTEMP(a, b, c)					\
    794 do {								\
    795 	if (b) 							\
    796 		(a) = ((b) / 1000000.0) - 273.15;		\
    797 	if (flags & ENVSYS_FFLAG) {				\
    798 		if (b)						\
    799 			(a) = (9.0 / 5.0) * (a) + 32.0;		\
    800 		(c) = "degF";					\
    801 	} else							\
    802 		(c) = "degC";					\
    803 } while (/* CONSTCOND */ 0)
    804 
    805 
    806 		/* temperatures */
    807 		} else if (strcmp(sensor->type, "Temperature") == 0) {
    808 
    809 			CONVERTTEMP(temp, sensor->cur_value, degrees);
    810 			stype = degrees;
    811 			(void)printf(": %10.3f ", temp);
    812 
    813 			if (statistics) {
    814 				/* show statistics if flag set */
    815 				CONVERTTEMP(temp, stats->max, degrees);
    816 				(void)printf("%8.3f ", temp);
    817 				CONVERTTEMP(temp, stats->min, degrees);
    818 				(void)printf("%8.3f ", temp);
    819 				CONVERTTEMP(temp, stats->avg, degrees);
    820 				(void)printf("%8.3f ", temp);
    821 				ilen = 8;
    822 			} else {
    823 				if (sensor->critmax_value) {
    824 					CONVERTTEMP(temp,
    825 					    sensor->critmax_value, degrees);
    826 					(void)printf( "%8.3f ", temp);
    827 					ilen = 24 + 2;
    828 				}
    829 
    830 				if (sensor->critmin_value) {
    831 					CONVERTTEMP(temp,
    832 					    sensor->critmin_value, degrees);
    833 					(void)printf("%8.3f ", temp);
    834 					if (sensor->critmax_value)
    835 						ilen = 16 + 1;
    836 					else
    837 						ilen = 24 + 2;
    838 				}
    839 			}
    840 
    841 			(void)printf("%*s", (int)ilen, stype);
    842 #undef CONVERTTEMP
    843 
    844 		/* fans */
    845 		} else if (strcmp(sensor->type, "Fan") == 0) {
    846 			stype = "RPM";
    847 
    848 			(void)printf(": %10u ", sensor->cur_value);
    849 			if (statistics) {
    850 				/* show statistics if flag set */
    851 				(void)printf("%8u %8u %8u ",
    852 				    stats->max, stats->min, stats->avg);
    853 				ilen = 8;
    854 			} else {
    855 				if (sensor->critmax_value) {
    856 					(void)printf("%8u ",
    857 					    sensor->critmax_value);
    858 					ilen = 24 + 2;
    859 				}
    860 
    861 				if (sensor->critmin_value) {
    862 					(void)printf("%8u ",
    863 					    sensor->critmin_value);
    864 					if (sensor->critmax_value)
    865 						ilen = 16 + 1;
    866 					else
    867 						ilen = 24 + 2;
    868 				}
    869 			}
    870 
    871 			(void)printf("%*s", (int)ilen, stype);
    872 
    873 		/* integers */
    874 		} else if (strcmp(sensor->type, "Integer") == 0) {
    875 
    876 			(void)printf(": %10d", sensor->cur_value);
    877 
    878 		/* drives  */
    879 		} else if (strcmp(sensor->type, "Drive") == 0) {
    880 
    881 			(void)printf(": %10s", sensor->drvstate);
    882 
    883 		/* Battery capacity */
    884 		} else if (strcmp(sensor->type, "Battery capacity") == 0) {
    885 
    886 			(void)printf(": %10s", sensor->battcap);
    887 
    888 		/* everything else */
    889 		} else {
    890 			if (strcmp(sensor->type, "Voltage DC") == 0)
    891 				stype = "V";
    892 			else if (strcmp(sensor->type, "Voltage AC") == 0)
    893 				stype = "VAC";
    894 			else if (strcmp(sensor->type, "Ampere") == 0)
    895 				stype = "A";
    896 			else if (strcmp(sensor->type, "Watts") == 0)
    897 				stype = "W";
    898 			else if (strcmp(sensor->type, "Ohms") == 0)
    899 				stype = "Ohms";
    900 			else if (strcmp(sensor->type, "Watt hour") == 0)
    901 				stype = "Wh";
    902 			else if (strcmp(sensor->type, "Ampere hour") == 0)
    903 				stype = "Ah";
    904 
    905 			(void)printf(": %10.3f ",
    906 			    sensor->cur_value / 1000000.0);
    907 
    908 			if (!statistics) {
    909 				if (sensor->critmax_value) {
    910 					(void)printf("%8.3f ",
    911 					    sensor->critmax_value / 1000000.0);
    912 					ilen = 24 + 2;
    913 				}
    914 
    915 				if (sensor->critmin_value) {
    916 					(void)printf("%8.3f ",
    917 					    sensor->critmin_value / 1000000.0);
    918 					if (sensor->critmax_value)
    919 						ilen = 16 + 1;
    920 					else
    921 						ilen = 24 + 2;
    922 				}
    923 
    924 				if (sensor->critcap_value) {
    925 					(void)printf("%8.2f%% ",
    926 					    (sensor->critcap_value * 100.0) /
    927 					    sensor->max_value);
    928 					ilen = 16 + 1;
    929 				}
    930 			}
    931 
    932 			if (statistics) {
    933 				/* show statistics if flag set */
    934 				(void)printf("%8.3f %8.3f %8.3f ",
    935 				    stats->max / 1000000.0,
    936 				    stats->min / 1000000.0,
    937 				    stats->avg / 1000000.0);
    938 				ilen = 8;
    939 			}
    940 
    941 			(void)printf("%*s", (int)ilen, stype);
    942 			if (sensor->percentage && sensor->max_value) {
    943 				(void)printf("  (%5.2f%%)",
    944 				    (sensor->cur_value * 100.0) /
    945 				    sensor->max_value);
    946 			}
    947 		}
    948 		(void)printf("\n");
    949 		ilen = 32 + 3;
    950 	}
    951 }
    952 
    953 static int
    954 usage(void)
    955 {
    956 	(void)fprintf(stderr, "Usage: %s [-DfIlrSTx] ", getprogname());
    957 	(void)fprintf(stderr, "[-c file] [-d device] [-i interval] ");
    958 	(void)fprintf(stderr, "[-s device:sensor,...] [-w width]\n");
    959 	exit(EXIT_FAILURE);
    960 	/* NOTREACHED */
    961 }
    962