add helper.c

contrib/helper.c

@@ -0,0 +1,63 @@
+/*
+ * this helper pretty similar to helper.sh, but it
+ * doesn't write unrelated variables to file (e.g PWD or PATH)
+ *
+ * build:
+ * cc helper.c -o helper
+ *
+ * usage:
+ * echo /full/path/to/helper > /proc/sys/kernel/hotplug
+ * echo "/full/path/to/helper UDEV_MONITOR_DIR" > /proc/sys/kernel/hotplug
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <limits.h>
+
+int main(int argc, char **argv)
+{
+    extern char **environ;
+    char path[PATH_MAX];
+    char *dir;
+    int fd, i;
+
+    switch (argc) {
+    case 1:
+        dir = "/tmp/.libudev-zero";
+        break;
+    case 2:
+        dir = argv[1];
+        break;
+    default:
+        fprintf(stderr, "usage: %s [dir]\n", argv[0]);
+        return 1;
+    }
+
+    snprintf(path, sizeof(path), "%s/uevent.XXXXXX", dir);
+    fd = mkstemp(path);
+
+    if (fd == -1) {
+        perror("mkstemp");
+        return 1;
+    }
+
+    for (i = 0; environ[i]; i++) {
+        if (strncmp(environ[i], "PATH", 4) == 0 ||
+            strncmp(environ[i], "HOME", 4) == 0) {
+            continue;
+        }
+
+        if (write(fd, environ[i], strlen(environ[i])) == -1 ||
+            write(fd, "\n", 1) == -1) {
+            perror("write");
+            close(fd);
+            unlink(path);
+            return 1;
+        }
+    }
+
+    close(fd);
+    return 0;
+}

udev_monitor.c

@@ -266,7 +266,7 @@ struct udev_monitor *udev_monitor_new_from_netlink(struct udev *udev, const char
         return NULL;
     }
 
-    if (inotify_add_watch(udev_monitor->ifd, UDEV_MONITOR_DIR, IN_CLOSE_WRITE) == -1) {
+    if (inotify_add_watch(udev_monitor->ifd, UDEV_MONITOR_DIR, IN_CLOSE_WRITE | IN_EXCL_UNLINK) == -1) {
         close(udev_monitor->ifd);
         close(udev_monitor->efd);
         free(udev_monitor);