gpiomon: code shrink

Use tools-common like other tools. Convert the program to using the
simple event monitoring interface.

Signed-off-by: Bartosz Golaszewski <bartekgola@gmail.com>

diff --git a/gpiomon.c b/gpiomon.c
index d9dbcfa149be41523de1765dc168f1ff1455cb30..9b40472c97a00fa4cd52eab0b52ba3b5674afd75 100644 (file)
--- a/gpiomon.c
+++ b/gpiomon.c
@@ -9,101 +9,103 @@
  */
 
 #include "gpiod.h"
+#include "tools-common.h"
 
 #include <stdio.h>
 #include <string.h>
+#include <getopt.h>
 
-int main(int argc, char **argv)
-{
-       struct gpiod_line_evreq_config config;
-       struct gpiod_line_event event;
-       struct timespec timeout;
-       struct gpiod_chip *chip;
-       struct gpiod_line *line;
-       unsigned int offset;
-       char *device, *end;
-       int status;
+static const struct option longopts[] = {
+       { "help",       no_argument,    NULL,   'h' },
+       { "active-low", no_argument,    NULL,   'l' },
+       { 0 },
+};
 
-       if (argc < 2) {
-               fprintf(stderr, "%s: gpiochip must be specified\n", argv[0]);
-               return EXIT_FAILURE;
-       }
+static const char *const shortopts = "hl";
 
-       if (argc < 3) {
-               fprintf(stderr,
-                       "%s: gpio line offset must be specified\n", argv[0]);
-               return EXIT_FAILURE;
-       }
+static void print_help(void)
+{
+       printf("Usage: %s [CHIP NAME/NUMBER] [LINE OFFSET] <options>\n",
+              get_progname());
+       printf("Wait for events on a GPIO line\n");
+       printf("Options:\n");
+       printf("  -h, --help:\t\tdisplay this message and exit\n");
+       printf("  -l, --active-low:\tset the line active state to low\n");
+}
 
-       device = argv[1];
-       /* FIXME Handle negative numbers. */
-       offset = strtoul(argv[2], &end, 10);
-       if (*end != '\0') {
-               fprintf(stderr,
-                       "%s: invalid GPIO offset: %s\n", argv[0], argv[2]);
-               return EXIT_FAILURE;
+static int event_callback(int type, const struct timespec *ts,
+                         void *data UNUSED)
+{
+       const char *evname = NULL;
+
+       switch (type) {
+       case GPIOD_EVENT_CB_RISING_EDGE:
+               evname = " RISING EDGE";
+               break;
+       case GPIOD_EVENT_CB_FALLING_EDGE:
+               evname = "FALLING_EDGE";
+               break;
+       default:
+               break;
        }
 
-       chip = gpiod_chip_open_lookup(device);
-       if (!chip) {
-               fprintf(stderr,
-                       "%s: error accessing gpiochip %s: %s\n",
-                       argv[0], device, gpiod_strerror(gpiod_errno()));
-               return EXIT_FAILURE;
-       }
+       if (evname)
+               printf("GPIO EVENT: %s [%8ld.%09ld]\n",
+                      evname, ts->tv_sec, ts->tv_nsec);
 
-       line = gpiod_chip_get_line(chip, offset);
-       if (!line) {
-               fprintf(stderr,
-                       "%s: error accessing line %u: %s\n",
-                       argv[0], offset, gpiod_strerror(gpiod_errno()));
-               return EXIT_FAILURE;
-       }
+       return GPIOD_EVENT_CB_OK;
+}
 
-       memset(&config, 0, sizeof(config));
-       config.consumer = "gpiomon";
-       config.event_type = GPIOD_EVENT_BOTH_EDGES;
+int main(int argc, char **argv)
+{
+       bool active_low = false;
+       struct timespec timeout;
+       int optc, opti, status;
+       unsigned int offset;
+       char *device, *end;
 
-       status = gpiod_line_event_request(line, &config);
-       if (status < 0) {
-               fprintf(stderr,
-                       "%s: error requesting line event: %s\n",
-                       argv[0], gpiod_strerror(gpiod_errno()));
-               return EXIT_FAILURE;
-       }
+       set_progname(argv[0]);
 
        for (;;) {
-               timeout.tv_sec = 1;
-               timeout.tv_nsec = 0;
-
-               status = gpiod_line_event_wait(line, &timeout);
-               if (status < 0) {
-                       fprintf(stderr,
-                               "%s: error waiting for line event: %s\n",
-                               argv[0], gpiod_strerror(gpiod_errno()));
-                       return EXIT_FAILURE;
-               } else if (status == 0) {
-                       continue;
+               optc = getopt_long(argc, argv, shortopts, longopts, &opti);
+               if (optc < 0)
+                       break;
+
+               switch (optc) {
+               case 'h':
+                       print_help();
+                       return EXIT_SUCCESS;
+               case 'l':
+                       active_low = true;
+                       break;
+               case '?':
+                       die("try %s --help", get_progname());
+               default:
+                       abort();
                }
+       }
 
-               status = gpiod_line_event_read(line, &event);
-               if (status < 0) {
-                       fprintf(stderr,
-                               "%s: error reading the line event: %s\n",
-                               argv[0], gpiod_strerror(gpiod_errno()));
-                       return EXIT_FAILURE;
-               }
+       argc -= optind;
+       argv += optind;
 
-               printf("GPIO EVENT: %s [%ld.%ld]\n",
-                      event.event_type == GPIOD_EVENT_FALLING_EDGE
-                                                       ? "FALLING EDGE"
-                                                       : "RAISING EDGE",
-                      event.ts.tv_sec, event.ts.tv_nsec);
-       }
+       if (argc < 1)
+               die("gpiochip must be specified");
+
+       if (argc < 2)
+               die("gpio line offset must be specified");
+
+       device = argv[0];
+       offset = strtoul(argv[1], &end, 10);
+       if (*end != '\0')
+               die("invalid GPIO offset: %s", argv[1]);
+
+       timeout.tv_sec = 0;
+       timeout.tv_nsec = 500000000;
 
-       gpiod_line_event_release(line);
-       gpiod_line_release(line);
-       gpiod_chip_close(chip);
+       status = gpiod_simple_event_loop(device, offset, active_low,
+                                        &timeout, event_callback, NULL);
+       if (status < 0)
+               die_perror("error waiting for events");
 
        return EXIT_SUCCESS;
 }