[gcab] Add gcab_folder_get_file_by_name()

[Richard Hughes <rhughes src gnome org>]

commit bcecbd6f8c256ac19a32bca0aaa25355b5b35a3c
Author: Richard Hughes <richard hughsie com>
Date:   Fri Dec 15 11:21:21 2017 +0000

    Add gcab_folder_get_file_by_name()
    
    If we know the name of the file we want to process, using the pre-existing hash
    table is a lot quicker and more efficient than getting the file list and
    strcmp()ing the gcab_file_get_name() on each of the GCabFile's.

 libgcab/gcab-folder.c  |   17 +++++++++++++++++
 libgcab/gcab-folder.h  |    2 ++
 libgcab/libgcab.syms   |    1 +
 tests/gcab-self-test.c |    6 ++++++
 4 files changed, 26 insertions(+), 0 deletions(-)
---
diff --git a/libgcab/gcab-folder.c b/libgcab/gcab-folder.c
index c46f383..1a12371 100644
--- a/libgcab/gcab-folder.c
+++ b/libgcab/gcab-folder.c
@@ -366,6 +366,23 @@ gcab_folder_get_files (GCabFolder *self)
     return g_slist_reverse (g_slist_copy (self->files));
 }
 
+/**
+ * gcab_folder_get_file_by_name:
+ * @cabfolder: a #GCabFolder
+ * @name: a file name
+ *
+ * Gets a specific #GCabFile files contained in the @cabfolder.
+ *
+ * Returns: (transfer none): A #GCabFile, or %NULL if not found
+ **/
+GCabFile *
+gcab_folder_get_file_by_name (GCabFolder *self, const gchar *name)
+{
+    g_return_val_if_fail (GCAB_IS_FOLDER (self), NULL);
+    g_return_val_if_fail (name != NULL, NULL);
+    return g_hash_table_lookup (self->hash, name);
+}
+
 static gint
 sort_by_offset (GCabFile *a, GCabFile *b)
 {
diff --git a/libgcab/gcab-folder.h b/libgcab/gcab-folder.h
index e54a468..e4f7168 100644
--- a/libgcab/gcab-folder.h
+++ b/libgcab/gcab-folder.h
@@ -63,6 +63,8 @@ gboolean        gcab_folder_add_file          (GCabFolder *cabfolder,
                                                GError **error);
 guint           gcab_folder_get_nfiles        (GCabFolder *cabfolder);
 GSList *        gcab_folder_get_files         (GCabFolder *cabfolder);
+GCabFile *      gcab_folder_get_file_by_name  (GCabFolder *cabfolder,
+                                               const gchar *name);
 gint            gcab_folder_get_comptype      (GCabFolder *cabfolder);
 
 G_END_DECLS
diff --git a/libgcab/libgcab.syms b/libgcab/libgcab.syms
index 76bda2b..d14729b 100644
--- a/libgcab/libgcab.syms
+++ b/libgcab/libgcab.syms
@@ -45,4 +45,5 @@ LIBGCAB1_0.6 {
 LIBGCAB1_1.0 {
         gcab_file_set_date;
         gcab_folder_get_comptype;
+        gcab_folder_get_file_by_name;
 } LIBGCAB1_0.6;
diff --git a/tests/gcab-self-test.c b/tests/gcab-self-test.c
index b44a800..defd278 100644
--- a/tests/gcab-self-test.c
+++ b/tests/gcab-self-test.c
@@ -119,6 +119,12 @@ gcab_test_folder_func (void)
     ret = gcab_folder_add_file (cabfolder, cabfile2, FALSE, NULL, &error);
     g_assert_error (error, GCAB_ERROR, GCAB_ERROR_FORMAT);
     g_assert (!ret);
+
+    /* find using the hash table */
+    cabfile_tmp = gcab_folder_get_file_by_name (cabfolder, "test.bin");
+    g_assert_nonnull (cabfile_tmp);
+    cabfile_tmp = gcab_folder_get_file_by_name (cabfolder, "notgoingtoexist");
+    g_assert_null (cabfile_tmp);
 }
 
 static void