[libgit2-glib] Implement diff patch using GString

[Jesse van den Kieboom <jessevdk src gnome org>]

commit 068efc05dab74c669555b4989323d03639172775
Author: Jesse van den Kieboom <jessevdk gmail com>
Date:   Sat Jun 29 17:44:17 2013 +0200

    Implement diff patch using GString

 libgit2-glib/ggit-diff-patch.c |   29 ++++++++++++++++++++++-------
 1 files changed, 22 insertions(+), 7 deletions(-)
---
diff --git a/libgit2-glib/ggit-diff-patch.c b/libgit2-glib/ggit-diff-patch.c
index 47c70b8..d52d5de 100644
--- a/libgit2-glib/ggit-diff-patch.c
+++ b/libgit2-glib/ggit-diff-patch.c
@@ -80,6 +80,20 @@ ggit_diff_patch_unref (GgitDiffPatch *diff_patch)
        }
 }
 
+static int
+patch_to_string (const git_diff_delta *delta,
+                 const git_diff_range *range,
+                 char                  line_origin,
+                 const char           *content,
+                 size_t                content_len,
+                 void                 *payload)
+{
+       GString *s = payload;
+
+       g_string_append_len (s, content, content_len);
+       return content_len;
+}
+
 /**
  * ggit_diff_patch_to_string:
  * @diff_patch: a #GgitDiffPatch.
@@ -93,24 +107,25 @@ gchar *
 ggit_diff_patch_to_string (GgitDiffPatch  *diff_patch,
                            GError        **error)
 {
-       gchar *str;
        gint ret;
-       gchar *gstr;
+       GString *s;
 
        g_return_val_if_fail (diff_patch != NULL, NULL);
        g_return_val_if_fail (error == NULL || *error == NULL, NULL);
 
-       ret = git_diff_patch_to_str (&str, diff_patch->diff_patch);
+       s = g_string_new ("");
+
+       ret = git_diff_patch_print (diff_patch->diff_patch,
+                                   patch_to_string,
+                                   s);
 
        if (ret != GIT_OK)
        {
+               g_string_free (s, TRUE);
                return NULL;
        }
 
-       gstr = g_strdup (str);
-       free (str);
-
-       return gstr;
+       return g_string_free (s, FALSE);
 }
 
 typedef struct