tests: Fix warnings about unused results from g_string_free()

GLib 2.76 emits a warning if `g_string_free (_, FALSE)` is used without
using its return value, as it typically signifies a leak:
```
warning: ignoring return value of ‘g_string_free_and_steal’ declared
with attribute ‘warn_unused_result’ [-Wunused-result]
```

In this case, the libsoup example and test code did *not* leak because
it had already stolen the string data from `GString`. That’s a bit of a
layering violation (the string data briefly has two owners), so
rearrange the code to fix that and silence the warning.

Signed-off-by: Philip Withnall <pwithnall@endlessos.org>

2 files changed, 15 insertions, 6 deletions

diff --git a/examples/simple-httpd.c b/examples/simple-httpd.c
index ac2c2e54..10afda65 100644
--- a/examples/simple-httpd.c
+++ b/examples/simple-httpd.c
@@ -88,6 +88,8 @@ do_get (SoupServer *server, SoupServerMessage *msg, const char *path)
 	if (g_file_test (path, G_FILE_TEST_IS_DIR)) {
 		GString *listing;
 		char *index_path;
+		char *listing_str;
+		gsize listing_len;
 
 		slash = strrchr (path, '/');
 		if (!slash || slash[1]) {
@@ -109,11 +111,12 @@ do_get (SoupServer *server, SoupServerMessage *msg, const char *path)
 		g_free (index_path);
 
 		listing = get_directory_listing (path);
+		listing_len = listing->len;
+		listing_str = g_string_free (g_steal_pointer (&listing), FALSE);
 		soup_server_message_set_response (msg, "text/html",
 					   SOUP_MEMORY_TAKE,
-					   listing->str, listing->len);
+					   g_steal_pointer (&listing_str), listing_len);
 		soup_server_message_set_status (msg, SOUP_STATUS_OK, NULL);
-		g_string_free (listing, FALSE);
 		return;
 	}
 
diff --git a/tests/forms-test.c b/tests/forms-test.c
index 201ad454..a1af7b30 100644
--- a/tests/forms-test.c
+++ b/tests/forms-test.c
@@ -311,6 +311,8 @@ hello_callback (SoupServer        *server,
 	const char *content_type;
 	GString *buf;
 	const char *method;
+	char *buf_str;
+	gsize buf_len;
 
 	method = soup_server_message_get_method (msg);
 	if (method != SOUP_METHOD_GET && method != SOUP_METHOD_HEAD) {
@@ -351,10 +353,11 @@ hello_callback (SoupServer        *server,
 		}
 	}
 
+	buf_len = buf->len;
+	buf_str = g_string_free (g_steal_pointer (&buf), FALSE);
 	soup_server_message_set_response (msg, content_type,
 					  SOUP_MEMORY_TAKE,
-					  buf->str, buf->len);
-	g_string_free (buf, FALSE);
+					  g_steal_pointer (&buf_str), buf_len);
 	soup_server_message_set_status (msg, SOUP_STATUS_OK, NULL);
 }
 
@@ -368,6 +371,8 @@ md5_get_callback (SoupServer        *server,
 	const char *file = NULL, *md5sum = NULL, *fmt;
 	const char *content_type;
 	GString *buf;
+	char *buf_str;
+	gsize buf_len;
 
 	if (query) {
 		file = g_hash_table_lookup (query, "file");
@@ -397,10 +402,11 @@ md5_get_callback (SoupServer        *server,
 			g_string_append_printf (buf, "%s", md5sum);
 	}
 
+	buf_len = buf->len;
+	buf_str = g_string_free (g_steal_pointer (&buf), FALSE);
 	soup_server_message_set_response (msg, content_type,
 					  SOUP_MEMORY_TAKE,
-					  buf->str, buf->len);
-	g_string_free (buf, FALSE);
+					  g_steal_pointer (&buf_str), buf_len);
 	soup_server_message_set_status (msg, SOUP_STATUS_OK, NULL);
 }