[libgsf] GafInfileStdio: speed up case of large number of files

[Morten Welinder <mortenw src gnome org>]

commit e14298edf91380e0c5ba5586c8c56ceb6c4e18fa
Author: Morten Welinder <terra gnome org>
Date:   Sat Nov 22 12:06:07 2014 -0500

    GafInfileStdio: speed up case of large number of files

 ChangeLog              |    5 ++++
 NEWS                   |    1 +
 gsf/gsf-infile-stdio.c |   57 ++++++++++++++++++++++-------------------------
 3 files changed, 33 insertions(+), 30 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index 214ed5c..306fe15 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2014-11-22  Morten Welinder  <terra gnome org>
+
+       * gsf/gsf-infile-stdio.c (GsfInfileStdio): Use a GPtrArray instead
+       of a list for performance with large directories.
+
 2014-11-20  Morten Welinder  <terra gnome org>
 
        * gsf/gsf-input.c (gsf_input_read0): Fix 64-bit issue.
diff --git a/NEWS b/NEWS
index 26b765f..e0ae033 100644
--- a/NEWS
+++ b/NEWS
@@ -10,6 +10,7 @@ Morten:
        * Read zip files with 64k+ members.  [Part of #732209]
        * Read zip files members larger than 4G.  [Part of #732209]
        * Speed up zip file reading for lots of members.
+       * Speed up stdio directory handling with large number of files.
        * Fix various issues with files larger than 4G.
 
 --------------------------------------------------------------------------
diff --git a/gsf/gsf-infile-stdio.c b/gsf/gsf-infile-stdio.c
index a2dab7f..ed27542 100644
--- a/gsf/gsf-infile-stdio.c
+++ b/gsf/gsf-infile-stdio.c
@@ -36,8 +36,8 @@ static GObjectClass *parent_class;
 
 struct _GsfInfileStdio {
        GsfInfile parent;
-       char     *root;
-       GList    *children;
+       char *root;
+       GPtrArray *children;
 };
 
 typedef GsfInfileClass GsfInfileStdioClass;
@@ -48,25 +48,24 @@ gsf_infile_stdio_finalize (GObject *obj)
        GsfInfileStdio *ifs = GSF_INFILE_STDIO (obj);
 
        g_free (ifs->root);
-       g_list_foreach (ifs->children, (GFunc) g_free, NULL);
-       g_list_free (ifs->children);
-
+       g_ptr_array_free (ifs->children, TRUE);
        parent_class->finalize (obj);
 }
 
 static GsfInput *
 gsf_infile_stdio_dup (GsfInput *src_input, G_GNUC_UNUSED GError **err)
 {
-       GList *ptr;
        GsfInfileStdio *src = GSF_INFILE_STDIO (src_input);
+       unsigned ui;
 
        GsfInfileStdio *dst = g_object_new (GSF_INFILE_STDIO_TYPE, NULL);
        dst->root = g_strdup (src->root);
 
-       for (ptr = src->children; ptr != NULL ; ptr = ptr->next)
-               dst->children = g_list_prepend (dst->children,
-                       g_strdup (ptr->data));
-       dst->children = g_list_reverse (dst->children);
+       for (ui = 0; ui < src->children->len; ui++) {
+               const char *child = g_ptr_array_index (src->children, ui);
+               g_ptr_array_add (dst->children, g_strdup (child));
+       }
+
        return GSF_INPUT (dst);
 }
 
@@ -92,35 +91,34 @@ open_child (GsfInfileStdio *ifs, char const *name, GError **err)
        return child;
 }
 
-static GsfInput *
-gsf_infile_stdio_child_by_index (GsfInfile *infile, int target, GError **err)
+static char const *
+gsf_infile_stdio_name_by_index (GsfInfile *infile, int target)
 {
        GsfInfileStdio *ifs = GSF_INFILE_STDIO (infile);
-       char const *name = g_list_nth_data (ifs->children, target);
-
-       if (!name)
-               return NULL;
-
-       return open_child (ifs, name, err);
+       return (unsigned)target < ifs->children->len
+               ? g_ptr_array_index (ifs->children, target)
+               : NULL;
 }
 
-static char const *
-gsf_infile_stdio_name_by_index (GsfInfile *infile, int target)
+static GsfInput *
+gsf_infile_stdio_child_by_index (GsfInfile *infile, int target, GError **err)
 {
        GsfInfileStdio *ifs = GSF_INFILE_STDIO (infile);
-
-       return g_list_nth_data (ifs->children, target);
+       const char *name = gsf_infile_stdio_name_by_index (infile, target);
+       return name ? open_child (ifs, name, err) : NULL;
 }
 
 static GsfInput *
 gsf_infile_stdio_child_by_name (GsfInfile *infile, char const *name, GError **err)
 {
        GsfInfileStdio *ifs = GSF_INFILE_STDIO (infile);
-       GList *ptr;
+       unsigned ui;
 
-       for (ptr = ifs->children; ptr != NULL; ptr = ptr->next)
-               if (!strcmp (ptr->data, name))
+       for (ui = 0; ui < ifs->children->len; ui++) {
+               const char *child = g_ptr_array_index (ifs->children, ui);
+               if (!strcmp (child, name))
                        return open_child (ifs, name, err);
+       }
 
        return NULL;
 }
@@ -129,15 +127,14 @@ static int
 gsf_infile_stdio_num_children (GsfInfile *infile)
 {
        GsfInfileStdio *ifs = GSF_INFILE_STDIO (infile);
-
-       return g_list_length (ifs->children);
+       return ifs->children->len;
 }
 
 static void
 gsf_infile_stdio_init (GsfInfileStdio *ifs)
 {
        ifs->root = NULL;
-       ifs->children = NULL;
+       ifs->children = g_ptr_array_new_with_free_func (g_free);
 }
 
 static void
@@ -184,8 +181,8 @@ gsf_infile_stdio_new (char const *root, GError **err)
        ifs->root = g_strdup (root);
 
        while ((child = g_dir_read_name (dir)))
-               ifs->children = g_list_prepend (ifs->children,
-                                               g_strdup (child));
+               g_ptr_array_add (ifs->children, g_strdup (child));
+
        g_dir_close (dir);
 
        gsf_input_set_name_from_filename (GSF_INPUT (ifs), root);