[libgweather] Fix crash when pressing enter on an empty entry

[Paolo Borelli <pborelli src gnome org>]

commit baa6bce929aa869abc97b633416a4d1039a33261
Author: Paolo Borelli <pborelli gnome org>
Date:   Sat Feb 15 15:40:01 2014 +0100

    Fix crash when pressing enter on an empty entry

 libgweather/location-entry.c |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)
---
diff --git a/libgweather/location-entry.c b/libgweather/location-entry.c
index 7712879..55f469e 100644
--- a/libgweather/location-entry.c
+++ b/libgweather/location-entry.c
@@ -576,8 +576,12 @@ static char *
 find_word (const char *full_name, const char *word, int word_len,
           gboolean whole_word, gboolean is_first_word)
 {
-    char *p = (char *)full_name - 1;
+    char *p;
 
+    if (word == NULL || *word == '\0')
+        return NULL;
+
+    p = (char *)full_name - 1;
     while ((p = strchr (p + 1, *word))) {
        if (strncmp (p, word, word_len) != 0)
            continue;