libudev: monitor - replace far too expensive snprintf() with strlcpy()

[elogind.git] / udev / lib / libudev-monitor.c

diff --git a/udev/lib/libudev-monitor.c b/udev/lib/libudev-monitor.c
index ccfcd6afc518f6dc31a94d4c85a409879a409167..9f139170421bc21f75956a40e62bd92cd32f3c16 100644 (file)
--- a/udev/lib/libudev-monitor.c
+++ b/udev/lib/libudev-monitor.c
@@ -67,10 +67,9 @@ struct udev_monitor *udev_monitor_new_from_socket(struct udev *udev, const char
                return NULL;
        if (socket_path == NULL)
                return NULL;
-       udev_monitor = malloc(sizeof(struct udev_monitor));
+       udev_monitor = calloc(1, sizeof(struct udev_monitor));
        if (udev_monitor == NULL)
                return NULL;
-       memset(udev_monitor, 0x00, sizeof(struct udev_monitor));
        udev_monitor->refcount = 1;
        udev_monitor->udev = udev;
 
@@ -105,10 +104,9 @@ struct udev_monitor *udev_monitor_new_from_netlink(struct udev *udev)
 
        if (udev == NULL)
                return NULL;
-       udev_monitor = malloc(sizeof(struct udev_monitor));
+       udev_monitor = calloc(1, sizeof(struct udev_monitor));
        if (udev_monitor == NULL)
                return NULL;
-       memset(udev_monitor, 0x00, sizeof(struct udev_monitor));
        udev_monitor->refcount = 1;
        udev_monitor->udev = udev;
 
@@ -152,6 +150,13 @@ int udev_monitor_enable_receiving(struct udev_monitor *udev_monitor)
        return 0;
 }
 
+int udev_monitor_set_receive_buffer_size(struct udev_monitor *udev_monitor, int size)
+{
+       if (udev_monitor == NULL)
+               return -1;
+       return setsockopt(udev_monitor->sock, SOL_SOCKET, SO_RCVBUFFORCE, &size, sizeof(size));
+}
+
 /**
  * udev_monitor_ref:
  * @udev_monitor: udev monitor
@@ -245,6 +250,8 @@ struct udev_device *udev_monitor_receive_device(struct udev_monitor *udev_monito
        char buf[4096];
        size_t bufpos;
        int devpath_set = 0;
+       int subsystem_set = 0;
+       int action_set = 0;
        int maj = 0;
        int min = 0;
 
@@ -317,12 +324,17 @@ struct udev_device *udev_monitor_receive_device(struct udev_monitor *udev_monito
                        devpath_set = 1;
                } else if (strncmp(key, "SUBSYSTEM=", 10) == 0) {
                        udev_device_set_subsystem(udev_device, &key[10]);
+                       subsystem_set = 1;
                } else if (strncmp(key, "DEVNAME=", 8) == 0) {
                        udev_device_set_devnode(udev_device, &key[8]);
                } else if (strncmp(key, "DEVLINKS=", 9) == 0) {
-                       char *slink = &key[9];
-                       char *next = strchr(slink, ' ');
+                       char devlinks[UTIL_PATH_SIZE];
+                       char *slink;
+                       char *next;
 
+                       util_strlcpy(devlinks, &key[9], sizeof(devlinks));
+                       slink = devlinks;
+                       next = strchr(slink, ' ');
                        while (next != NULL) {
                                next[0] = '\0';
                                udev_device_add_devlink(udev_device, slink);
@@ -335,6 +347,7 @@ struct udev_device *udev_monitor_receive_device(struct udev_monitor *udev_monito
                        udev_device_set_driver(udev_device, &key[7]);
                } else if (strncmp(key, "ACTION=", 7) == 0) {
                        udev_device_set_action(udev_device, &key[7]);
+                       action_set = 1;
                } else if (strncmp(key, "MAJOR=", 6) == 0) {
                        maj = strtoull(&key[6], NULL, 10);
                } else if (strncmp(key, "MINOR=", 6) == 0) {
@@ -347,18 +360,20 @@ struct udev_device *udev_monitor_receive_device(struct udev_monitor *udev_monito
                        udev_device_set_seqnum(udev_device, strtoull(&key[7], NULL, 10));
                } else if (strncmp(key, "TIMEOUT=", 8) == 0) {
                        udev_device_set_timeout(udev_device, strtoull(&key[8], NULL, 10));
-               }
-               if (strncmp(key, "PHYSDEV", 7) == 0)
+               } else if (strncmp(key, "PHYSDEV", 7) == 0) {
+                       /* skip deprecated values */
                        continue;
-               udev_device_add_property_from_string(udev_device, key);
+               } else {
+                       udev_device_add_property_from_string(udev_device, key);
+               }
        }
-       if (!devpath_set) {
+       if (!devpath_set || !subsystem_set || !action_set) {
+               info(udev_monitor->udev, "missing values, skip\n");
                udev_device_unref(udev_device);
                return NULL;
        }
-
-       udev_device_set_devnum(udev_device, makedev(maj, min));
-
+       if (maj > 0)
+               udev_device_set_devnum(udev_device, makedev(maj, min));
        udev_device_set_info_loaded(udev_device);
        return udev_device;
 }
@@ -369,19 +384,37 @@ int udev_monitor_send_device(struct udev_monitor *udev_monitor, struct udev_devi
        struct udev_list_entry *list_entry;
        char buf[4096];
        size_t bufpos;
+       size_t len;
        ssize_t count;
 
        action = udev_device_get_action(udev_device);
        if (action == NULL)
                return -EINVAL;
-       bufpos = snprintf(buf, sizeof(buf), "%s@%s", action, udev_device_get_devpath(udev_device));
-       bufpos++;
+
+       bufpos = util_strlcpy(buf, action, sizeof(buf));
+       len = util_strlcpy(&buf[bufpos], "@", sizeof(buf)-bufpos);
+       if (len >= sizeof(buf)-bufpos)
+               return -1;
+       bufpos += len;
+       len = util_strlcpy(&buf[bufpos], udev_device_get_devpath(udev_device), sizeof(buf)-bufpos);
+       if (len+1 >= sizeof(buf)-bufpos)
+               return -1;
+       bufpos += len+1;
        udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device)) {
-               bufpos += snprintf(&buf[bufpos], sizeof(buf) - bufpos, "%s=%s",
-                                  udev_list_entry_get_name(list_entry),
-                                  udev_list_entry_get_value(list_entry));
-               bufpos++;
+               len = util_strlcpy(&buf[bufpos], udev_list_entry_get_name(list_entry), sizeof(buf)-bufpos);
+               if (len >= sizeof(buf)-bufpos)
+                       return -1;
+               bufpos += len;
+               len = util_strlcpy(&buf[bufpos], "=", sizeof(buf)-bufpos);
+               if (len >= sizeof(buf)-bufpos)
+                       return -1;
+               bufpos += len;
+               len = util_strlcpy(&buf[bufpos], udev_list_entry_get_value(list_entry), sizeof(buf)-bufpos);
+               if (len+1 >= sizeof(buf)-bufpos)
+                       return -1;
+               bufpos += len+1;
        }
+
        count = sendto(udev_monitor->sock,
                       &buf, bufpos, 0,
                       (struct sockaddr *)&udev_monitor->sun, udev_monitor->addrlen);