package/network/utils/rssileds/src/rssileds.c

   1 /*
   2  * configurable RSSI LED control daemon for OpenWrt
   3  *  (c) 2012 Allnet GmbH, Daniel Golle <dgolle@allnet.de>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  18  *
  19  * The author may be reached as dgolle@allnet.de, or
  20  * ALLNET GmbH
  21  * Maistr. 2
  22  * D-82110 Germering
  23  * Germany
  24  *
  25  */
  26
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <sys/stat.h>
  30 #include <fcntl.h>
  31 #include <signal.h>
  32 #include <unistd.h>
  33 #include <syslog.h>
  34
  35 #include "iwinfo.h"
  36
  37 #define RUN_DIR                 "/var/run"
  38 #define LEDS_BASEPATH           "/sys/class/leds/"
  39 #define BACKEND_RETRY_DELAY     500000
  40
  41 char *ifname;
  42 int qual_max;
  43
  44 struct led {
  45         char *sysfspath;
  46         FILE *controlfd;
  47         unsigned char state;
  48 };
  49
  50 typedef struct rule rule_t;
  51 struct rule {
  52         struct led *led;
  53         int minq;
  54         int maxq;
  55         int boffset;
  56         int bfactor;
  57         rule_t *next;
  58 };
  59
  60 void log_rules(rule_t *rules)
  61 {
  62         rule_t *rule = rules;
  63         while (rule)
  64         {
  65                 syslog(LOG_INFO, " %s r: %d..%d, o: %d, f: %d\n",
  66                         rule->led->sysfspath,
  67                         rule->minq, rule->maxq,
  68                         rule->boffset, rule->bfactor);
  69                 rule = rule->next;
  70         }
  71 }
  72
  73 int init_led(struct led **led, char *ledname)
  74 {
  75         struct led *newled;
  76         struct stat statbuffer;
  77         int status;
  78         char *bp;
  79         FILE *bfp;
  80
  81         bp = calloc(sizeof(char), strlen(ledname) + strlen(LEDS_BASEPATH) + 12);
  82         if ( ! bp )
  83                 goto return_error;
  84
  85         sprintf(bp, "%s%s/brightness", LEDS_BASEPATH, ledname);
  86
  87         status = stat(bp, &statbuffer);
  88         if ( status )
  89                 goto cleanup_fname;
  90
  91         bfp = fopen( bp, "w" );
  92         if ( !bfp )
  93                 goto cleanup_fname;
  94
  95         if ( ferror(bfp) )
  96                 goto cleanup_fp;
  97
  98         /* sysfs path exists and, allocate LED struct */
  99         newled = calloc(sizeof(struct led),1);
 100         if ( !newled )
 101                 goto cleanup_fp;
 102
 103         newled->sysfspath = bp;
 104         newled->controlfd = bfp;
 105
 106         *led = newled;
 107         return 0;
 108
 109 cleanup_fp:
 110         fclose(bfp);
 111 cleanup_fname:
 112         free(bp);
 113 return_error:
 114         syslog(LOG_CRIT, "can't open LED %s\n", ledname);
 115         *led = NULL;
 116         return -1;
 117 }
 118
 119 void close_led(struct led **led)
 120 {
 121         fclose((*led)->controlfd);
 122         free((*led)->sysfspath);
 123         free((*led));
 124         (*led)=NULL;
 125 }
 126
 127 int set_led(struct led *led, unsigned char value)
 128 {
 129         char buf[8];
 130
 131         if ( ! led )
 132                 return -1;
 133
 134         if ( ! led->controlfd )
 135                 return -1;
 136
 137         snprintf(buf, 8, "%d", value);
 138
 139         rewind(led->controlfd);
 140
 141         if ( ! fwrite(buf, sizeof(char), strlen(buf), led->controlfd) )
 142                 return -2;
 143
 144         fflush(led->controlfd);
 145         led->state=value;
 146
 147         return 0;
 148 }
 149
 150
 151 int quality(const struct iwinfo_ops *iw, const char *ifname)
 152 {
 153         int qual;
 154
 155         if ( ! iw ) return -1;
 156
 157         if (qual_max < 1)
 158                 if (iw->quality_max(ifname, &qual_max))
 159                         return -1;
 160
 161         if (iw->quality(ifname, &qual))
 162                 return -1;
 163
 164         return ( qual * 100 ) / qual_max ;
 165 }
 166
 167 int open_backend(const struct iwinfo_ops **iw, const char *ifname)
 168 {
 169         *iw = iwinfo_backend(ifname);
 170
 171         if (!(*iw))
 172                 return 1;
 173
 174         return 0;
 175 }
 176
 177 void update_leds(rule_t *rules, int q)
 178 {
 179         rule_t *rule = rules;
 180         while (rule)
 181         {
 182                 int b;
 183                 /* offset and factore correction according to rule */
 184                 b = ( q + rule->boffset ) * rule->bfactor;
 185                 if ( b < 0 )
 186                         b=0;
 187                 if ( b > 255 )
 188                         b=255;
 189
 190                 if ( q >= rule->minq && q <= rule->maxq )
 191                         set_led(rule->led, (unsigned char)b);
 192                 else
 193                         set_led(rule->led, 0);
 194
 195                 rule = rule->next;
 196         }
 197 }
 198
 199 int main(int argc, char **argv)
 200 {
 201         int i,q,q0,r,s;
 202         const struct iwinfo_ops *iw = NULL;
 203         rule_t *headrule = NULL, *currentrule = NULL;
 204
 205         if (argc < 9 || ( (argc-4) % 5 != 0 ) )
 206         {
 207                 printf("syntax: %s (ifname) (refresh) (threshold) (rule) [rule] ...\n", argv[0]);
 208                 printf("  rule: (sysfs-name) (minq) (maxq) (offset) (factore)\n");
 209                 return 1;
 210         }
 211
 212         ifname = argv[1];
 213
 214         /* refresh interval */
 215         if ( sscanf(argv[2], "%d", &r) != 1 )
 216                 return 1;
 217
 218         /* sustain threshold */
 219         if ( sscanf(argv[3], "%d", &s) != 1 )
 220                 return 1;
 221
 222         openlog("rssileds", LOG_PID, LOG_DAEMON);
 223         syslog(LOG_INFO, "monitoring %s, refresh rate %d, threshold %d\n", ifname, r, s);
 224
 225         currentrule = headrule;
 226         for (i=4; i<argc; i=i+5) {
 227                 if (! currentrule)
 228                 {
 229                         /* first element in the list */
 230                         currentrule = calloc(sizeof(rule_t),1);
 231                         headrule = currentrule;
 232                 }
 233                 else
 234                 {
 235                         /* follow-up element */
 236                         currentrule->next = calloc(sizeof(rule_t),1);
 237                         currentrule = currentrule->next;
 238                 }
 239
 240                 if ( init_led(&(currentrule->led), argv[i]) )
 241                         return 1;
 242
 243                 if ( sscanf(argv[i+1], "%d", &(currentrule->minq)) != 1 )
 244                         return 1;
 245
 246                 if ( sscanf(argv[i+2], "%d", &(currentrule->maxq)) != 1 )
 247                         return 1;
 248
 249                 if ( sscanf(argv[i+3], "%d", &(currentrule->boffset)) != 1 )
 250                         return 1;
 251
 252                 if ( sscanf(argv[i+4], "%d", &(currentrule->bfactor)) != 1 )
 253                         return 1;
 254         }
 255         log_rules(headrule);
 256
 257         q0 = -1;
 258         do {
 259                 q = quality(iw, ifname);
 260                 if ( q < q0 - s || q > q0 + s ) {
 261                         update_leds(headrule, q);
 262                         q0=q;
 263                 };
 264                 // re-open backend...
 265                 if ( q == -1 && q0 == -1 ) {
 266                         if (iw) {
 267                                 iwinfo_finish();
 268                                 iw=NULL;
 269                                 usleep(BACKEND_RETRY_DELAY);
 270                         }
 271                         while (open_backend(&iw, ifname))
 272                                 usleep(BACKEND_RETRY_DELAY);
 273                 }
 274                 usleep(r);
 275         } while(1);
 276
 277         iwinfo_finish();
 278
 279         return 0;
 280 }