tools: use ppoll() where higher timeout resolution makes sense

We allow timeout units to be specified in microseconds but for poll() we
need to round them up to milliseconds. Switch to ppoll() to avoid losing
precision.

Reviewed-by: Kent Gibson <warthog618@gmail.com>
Link: https://lore.kernel.org/r/20240423100452.32958-3-brgl@bgdev.pl
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

diff --git a/tools/gpiomon.c b/tools/gpiomon.c
index 40e6ac2ff8f2c05ccf13bc35dca5b47d402ba2cf..7135843348dbb204208a7ae14fb60574b962f7ff 100644 (file)
--- a/tools/gpiomon.c
+++ b/tools/gpiomon.c
@@ -176,7 +176,7 @@ static int parse_config(int argc, char **argv, struct config *cfg)
                        cfg->fmt = optarg;
                        break;
                case 'i':
-                       cfg->idle_timeout = parse_period_or_die(optarg) / 1000;
+                       cfg->idle_timeout = parse_period_or_die(optarg);
                        break;
                case 'l':
                        cfg->active_low = true;
@@ -362,6 +362,7 @@ int main(int argc, char **argv)
        int num_lines, events_done = 0;
        struct gpiod_edge_event *event;
        struct line_resolver *resolver;
+       struct timespec idle_timeout;
        struct gpiod_chip *chip;
        struct pollfd *pollfds;
        unsigned int *offsets;
@@ -450,10 +451,17 @@ int main(int argc, char **argv)
        if (cfg.banner)
                print_banner(argc, argv);
 
+       if (cfg.idle_timeout > 0) {
+               idle_timeout.tv_sec = cfg.idle_timeout / 1000000;
+               idle_timeout.tv_nsec =
+                               (cfg.idle_timeout % 1000000) * 1000;
+       }
+
        for (;;) {
                fflush(stdout);
 
-               ret = poll(pollfds, resolver->num_chips, cfg.idle_timeout);
+               ret = ppoll(pollfds, resolver->num_chips,
+                           cfg.idle_timeout > 0 ? &idle_timeout : NULL, NULL);
                if (ret < 0)
                        die_perror("error polling for events");
 

diff --git a/tools/gpionotify.c b/tools/gpionotify.c
index d2aee152b0daa218f01a8e798d7cda93b05e36e8..08f5da93b6f516ae497928cec53920ef28e3322f 100644 (file)
--- a/tools/gpionotify.c
+++ b/tools/gpionotify.c
@@ -132,7 +132,7 @@ static int parse_config(int argc, char **argv, struct config *cfg)
                        cfg->fmt = optarg;
                        break;
                case 'i':
-                       cfg->idle_timeout = parse_period_or_die(optarg) / 1000;
+                       cfg->idle_timeout = parse_period_or_die(optarg);
                        break;
                case 'n':
                        cfg->events_wanted = parse_uint_or_die(optarg);
@@ -374,6 +374,7 @@ int main(int argc, char **argv)
        int i, j, ret, events_done = 0, evtype;
        struct line_resolver *resolver;
        struct gpiod_info_event *event;
+       struct timespec idle_timeout;
        struct gpiod_chip **chips;
        struct gpiod_chip *chip;
        struct pollfd *pollfds;
@@ -419,10 +420,17 @@ int main(int argc, char **argv)
        if (cfg.banner)
                print_banner(argc, argv);
 
+       if (cfg.idle_timeout > 0) {
+               idle_timeout.tv_sec = cfg.idle_timeout / 1000000;
+               idle_timeout.tv_nsec =
+                               (cfg.idle_timeout % 1000000) * 1000;
+       }
+
        for (;;) {
                fflush(stdout);
 
-               ret = poll(pollfds, resolver->num_chips, cfg.idle_timeout);
+               ret = ppoll(pollfds, resolver->num_chips,
+                           cfg.idle_timeout > 0 ? &idle_timeout : NULL, NULL);
                if (ret < 0)
                        die_perror("error polling for events");