[gnome-session] tools: don't check software rendering before GLES helper

[Ray Strode <halfline src gnome org>]

commit 3bbd649870af9cb81e8c3ec6a24f07e8d20e1be7
Author: Cosimo Cecchi <cosimo endlessm com>
Date:   Tue Nov 7 17:36:24 2017 -0800

    tools: don't check software rendering before GLES helper
    
    A regression from 51d1e18193f74a53e32667cf1b550f889027fdf1 -- the code
    is currently skipping GLES checks when software rendering is in use.
    
    Instead, it should first try to use the GLES helper, or animations will
    be disabled on devices such as ARM machines, which are not compatible
    with desktop GL.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=768292

 .../gnome-session-check-accelerated-gles-helper.c  |    9 ++++-
 tools/gnome-session-check-accelerated.c            |   39 +++++++++++++++-----
 2 files changed, 38 insertions(+), 10 deletions(-)
---
diff --git a/tools/gnome-session-check-accelerated-gles-helper.c 
b/tools/gnome-session-check-accelerated-gles-helper.c
index 2a38d9e..6a4463d 100644
--- a/tools/gnome-session-check-accelerated-gles-helper.c
+++ b/tools/gnome-session-check-accelerated-gles-helper.c
@@ -21,11 +21,15 @@
  *   Cosimo Cecchi <cosimo endlessm com>
  */
 
+/* for strcasestr */
+#define _GNU_SOURCE
+
 #include <config.h>
 
 #include <gtk/gtk.h>
 #include <locale.h>
 #include <stdlib.h>
+#include <string.h>
 
 #ifdef GDK_WINDOWING_X11
 #define GL_GLEXT_PROTOTYPES
@@ -186,7 +190,10 @@ main (int argc,
         if (renderer != NULL) {
                 if (print_renderer)
                         g_print ("%s", renderer);
-                ret = HELPER_ACCEL;
+                if (strcasestr (renderer, "llvmpipe"))
+                        ret = HELPER_SOFTWARE_RENDERING;
+                else
+                        ret = HELPER_ACCEL;
         }
 
 out:
diff --git a/tools/gnome-session-check-accelerated.c b/tools/gnome-session-check-accelerated.c
index b914394..344c654 100644
--- a/tools/gnome-session-check-accelerated.c
+++ b/tools/gnome-session-check-accelerated.c
@@ -133,6 +133,8 @@ main (int argc, char **argv)
         char *gl_helper_argv[] = { LIBEXECDIR "/gnome-session-check-accelerated-gl-helper", 
"--print-renderer", NULL };
         char *gles_helper_argv[] = { LIBEXECDIR "/gnome-session-check-accelerated-gles-helper", 
"--print-renderer", NULL };
         char *renderer_string = NULL;
+        char *gl_renderer_string = NULL, *gles_renderer_string = NULL;
+        gboolean gl_software_rendering = FALSE, gles_software_rendering = FALSE;
         Window rootwin;
         glong is_accelerated, is_software_rendering;
         GError *gl_error = NULL, *gles_error = NULL;
@@ -220,27 +222,43 @@ main (int argc, char **argv)
 
         /* First, try the GL helper */
         if (g_spawn_sync (NULL, (char **) gl_helper_argv, NULL, 0,
-                           NULL, NULL, &renderer_string, NULL, &estatus, &gl_error)) {
-                is_accelerated = (WEXITSTATUS(estatus) == HELPER_ACCEL) || (WEXITSTATUS(estatus) == 
HELPER_SOFTWARE_RENDERING);
-                is_software_rendering = (WEXITSTATUS(estatus) == HELPER_SOFTWARE_RENDERING);
-                if (is_accelerated || is_software_rendering)
+                           NULL, NULL, &gl_renderer_string, NULL, &estatus, &gl_error)) {
+                is_accelerated = (WEXITSTATUS(estatus) == HELPER_ACCEL);
+                gl_software_rendering = (WEXITSTATUS(estatus) == HELPER_SOFTWARE_RENDERING);
+                if (is_accelerated) {
+                        renderer_string = gl_renderer_string;
                         goto finish;
+                }
 
-                g_clear_pointer (&renderer_string, g_free);
                 g_printerr ("gnome-session-check-accelerated: GL Helper exited with code %d\n", estatus);
         }
 
         /* Then, try the GLES helper */
         if (g_spawn_sync (NULL, (char **) gles_helper_argv, NULL, 0,
-                           NULL, NULL, &renderer_string, NULL, &estatus, &gles_error)) {
+                           NULL, NULL, &gles_renderer_string, NULL, &estatus, &gles_error)) {
                 is_accelerated = (WEXITSTATUS(estatus) == HELPER_ACCEL);
-                if (is_accelerated)
+                gles_software_rendering = (WEXITSTATUS(estatus) == HELPER_SOFTWARE_RENDERING);
+                if (is_accelerated) {
+                        renderer_string = gles_renderer_string;
                         goto finish;
+                }
 
-                g_clear_pointer (&renderer_string, g_free);
                 g_printerr ("gnome-session-check-accelerated: GLES Helper exited with code %d\n", estatus);
         }
 
+        /* If we got here, GL software rendering is our best bet */
+        if (gl_software_rendering || gles_software_rendering) {
+                is_software_rendering = TRUE;
+                is_accelerated = TRUE;
+
+                if (gl_software_rendering)
+                        renderer_string = gl_renderer_string;
+                else if (gles_software_rendering)
+                        renderer_string = gles_renderer_string;
+
+                goto finish;
+        }
+
         /* Both helpers failed; print their error messages */
         if (gl_error != NULL) {
                 g_printerr ("gnome-session-check-accelerated: Failed to run GL helper: %s\n", 
gl_error->message);
@@ -267,7 +285,7 @@ main (int argc, char **argv)
                                XA_CARDINAL, 32, PropModeReplace, (guchar *) &is_software_rendering, 1);
        }
 
-        if (is_accelerated || is_software_rendering) {
+        if (renderer_string != NULL) {
                 XChangeProperty (GDK_DISPLAY_XDISPLAY (display),
                                rootwin,
                                renderer_atom,
@@ -279,5 +297,8 @@ main (int argc, char **argv)
 
         gdk_display_sync (display);
 
+        g_free (gl_renderer_string);
+        g_free (gles_renderer_string);
+
         return is_accelerated ? 0 : 1;
 }