[libgsf] GsfInputMemory: Handle zero-sized files better.

[Morten Welinder <mortenw src gnome org>]

commit 58e66b05124cb0e34f83969cbfab59cd7814c5be
Author: Morten Welinder <terra gnome org>
Date:   Sat Apr 25 14:14:32 2009 -0400

    GsfInputMemory: Handle zero-sized files better.
---
 ChangeLog              |    6 ++++++
 NEWS                   |    9 ++++++---
 gsf/gsf-input-memory.c |   10 +++++-----
 3 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index f85f5a7..c3de3e3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2009-04-25  Morten Welinder  <terra gnome org>
+
+	* gsf/gsf-input-memory.c (gsf_input_memory_new_clone): Fix
+	preconditions.  Always allocate at least one byte.  Avoid cast.
+	Fixes #580228.
+
 2009-04-17  Morten Welinder  <terra gnome org>
 
 	* gsf/gsf-output.c (gsf_output_set_error): Fix allocation method
diff --git a/NEWS b/NEWS
index 294c6ea..9afe899 100644
--- a/NEWS
+++ b/NEWS
@@ -1,7 +1,7 @@
 libgsf 1.14.12
 
 Andreas:
-	* also read user defined OpenDocument metadata
+	* Also read user defined OpenDocument metadata
 
 Christian Persch:
 	* Fix allocation method problem.  [#579155]
@@ -13,13 +13,16 @@ J.H.M. Dassen (Ray):
 
 Jody :
 	* Handle small-block files that are not block aligned. [#572290]
-	* Deprecate gsf_timestamp_parse and replace it with gsf_timestamp_from_string.
+	* Deprecate gsf_timestamp_parse and replace it with
+	  gsf_timestamp_from_string.
 	* Gtk-Doc fixes.
-	* Fix handling of namespace declared default and prefix. (SpreadsheetML-2003)
+	* Fix handling of namespace declared default and prefix.
+	  (Such as in SpreadsheetML-2003)
 
 Morten:
 	* Handle malformed xml better.  [#568994]
 	* Drop characters that xml 1.0 cannot represent.  [#568919]
+	* Fix problem loading zero-sized files.  [#580228]
 
 --------------------------------------------------------------------------
 libgsf 1.14.11
diff --git a/gsf/gsf-input-memory.c b/gsf/gsf-input-memory.c
index c2ffc24..98a51a0 100644
--- a/gsf/gsf-input-memory.c
+++ b/gsf/gsf-input-memory.c
@@ -93,21 +93,21 @@ GsfInput *
 gsf_input_memory_new_clone (guint8 const *buf, gsf_off_t length)
 {
 	GsfInputMemory *mem = NULL;
-	guint8 *cpy;
+	void *cpy;
 
-	g_return_val_if_fail (buf != NULL, NULL);
-	g_return_val_if_fail (length > 0, NULL);
+	g_return_val_if_fail (buf != NULL || length == 0, NULL);
+	g_return_val_if_fail (length >= 0, NULL);
 
 	mem = g_object_new (GSF_INPUT_MEMORY_TYPE, NULL);
 	if (G_UNLIKELY (NULL == mem)) return NULL;
 
-	cpy = g_try_malloc (length * sizeof (guint8));
+	cpy = g_try_malloc (MAX (1, length) * sizeof (guint8));
 	if (cpy == NULL) {
 		g_object_unref (mem);
 		return NULL;
 	}
 	memcpy (cpy, buf, length);
-	mem->shared = gsf_shared_memory_new ((void *)cpy, length, TRUE);
+	mem->shared = gsf_shared_memory_new (cpy, length, TRUE);
 	gsf_input_set_size (GSF_INPUT (mem), length);
 	return GSF_INPUT (mem);
 }