1 files changed, 93 insertions, 0 deletions
diff --git a/meta-facebook/meta-wedge/recipes-wedge/rackmon/rackmon/gpiowatch.c b/meta-facebook/meta-wedge/recipes-wedge/rackmon/rackmon/gpiowatch.c
new file mode 100644
index 0000000..11b5471
--- /dev/null
+++ b/meta-facebook/meta-wedge/recipes-wedge/rackmon/rackmon/gpiowatch.c
@@ -0,0 +1,93 @@
+/*
+ * Copyright 2014-present Facebook. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <fcntl.h>
+
+#define CHECK(x) { if((x) < 0) { \
+    error = x;  \
+    goto cleanup; \
+} }
+
+#define CHECKNULL(x) { if((x) == NULL) { \
+    error = -1;  \
+    goto cleanup; \
+} }
+
+typedef struct {
+  int fd;
+  int gpio;
+  char value;
+} wgpio;
+
+int main(int argc, char **argv) {
+    int error = 0;
+    int nfds =  argc - 1;
+    int i = 0;
+    int polliv = 10000;
+    wgpio* wgpios = NULL;
+
+    if(argc < 2) {
+      fprintf(stderr, "Usage: %s <gpio num> [gpio num] [gpio num...]\n", argv[0]);
+      exit(1);
+    }
+    if(getenv("POLL_US")) {
+      polliv = atoi(getenv("POLL_US"));
+    }
+
+    wgpios = calloc(nfds, sizeof(wgpio));
+    CHECKNULL(wgpios)
+
+    fprintf(stderr, "Watching %d gpios:", nfds);
+    for(i = 1; i < argc; i++) {
+      char filename[255];
+      int gpio_num = atoi(argv[i]);
+      wgpios[i - 1].gpio = gpio_num;
+      snprintf(filename, 255, "/sys/class/gpio/gpio%d/value", gpio_num);
+      wgpios[i - 1].fd = open(filename, O_RDONLY);
+      CHECK(wgpios[i - 1].fd);
+      CHECK(read(wgpios[i - 1].fd, &(wgpios[i - 1].value), 1));
+      fprintf(stderr, " %d (currently: %c)", gpio_num, wgpios[i - 1].value);
+    }
+    fprintf(stderr, "\n");
+
+    do {
+      usleep(polliv);
+      for(i = 0; i < nfds; i++) {
+          wgpio* w = &wgpios[i];
+          char value;
+          lseek(w->fd, 0, SEEK_SET);
+          CHECK(read(w->fd, &value, 1));
+          if(value != w->value) {
+            printf("GPIO%d: %c -> %c\n", w->gpio, w->value, value);
+            w->value = value;
+          }
+      }
+    } while (1);
+
+cleanup:
+    if(error != 0) {
+      fprintf(stderr, "Error %d: %s\n", errno, strerror(errno));
+      error = 1;
+    }
+    return error;
+}