X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=string.c;h=198e9f1d286ee2228638a2a7994fe9e65f41ccac;hp=e675502cf6707240a61be523c6fb510692991acd;hb=0c7c4d80673854527ce3c3786dd581169565b5e6;hpb=10a62b85c43319d9cdefd7d04823aaed47b3817e

diff --git a/string.c b/string.c
index e675502c..198e9f1d 100644
--- a/string.c
+++ b/string.c
@@ -1,8 +1,4 @@
-/*
- * Copyright (C) 2004 Andre Noll <maan@tuebingen.mpg.de>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2004 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
 
 /** \file string.c Memory allocation and string handling functions. */
 
@@ -117,9 +113,9 @@ __must_check __malloc char *para_strdup(const char *s)
 }
 
 /**
- * Print a formated message to a dynamically allocated string.
+ * Print a formatted message to a dynamically allocated string.
  *
- * \param result The formated string is returned here.
+ * \param result The formatted string is returned here.
  * \param fmt The format string.
  * \param ap Initialized list of arguments.
  *
@@ -203,17 +199,22 @@ __must_check __printf_1_2 __malloc char *make_message(const char *fmt, ...)
 }
 
 /**
- * Free the content of a pointer and set it to \p NULL.
+ * Free the content of a pointer and set it to NULL.
  *
- * This is equivalent to "free(*arg); *arg = NULL;".
+ * \param arg A pointer to the pointer whose content should be freed.
  *
- * \param arg The pointer whose content should be freed.
+ * If arg is NULL, the function returns immediately. Otherwise it frees the
+ * memory pointed to by *arg and sets *arg to NULL. Hence callers have to pass
+ * the *address* of the pointer variable that points to the memory which should
+ * be freed.
  */
 void freep(void *arg)
 {
-	void **ptr = (void **)arg;
-	free(*ptr);
-	*ptr = NULL;
+	if (arg) {
+		void **ptr = arg;
+		free(*ptr);
+		*ptr = NULL;
+	}
 }
 
 /**