From 1dd5fbc5a4d860af1c102b33e04dedd8c72617a1 Mon Sep 17 00:00:00 2001
From: Ruediger Oertel <ro@suse.de>
Date: Fri, 26 Mar 2010 09:33:20 -0700
Subject: [PATCH] xfree86: Handle driver autoconfiguration when .conf files
 exist

When doing driver autoconfiguration with some parts of the config file
present but no driver set (e.g. only input configuration) fix the case
that we may have multiple drivers to try.

Create a screen section for each driver and let them be tried in a row.

Signed-off-by: Ruediger Oertel <ro@suse.de>
Reviewed-by: Dan Nicholson <dbn.lists@gmail.com>
Tested-by: Timo Aaltonen <timo.aaltonen@aalto.fi>
Signed-off-by: Keith Packard <keithp@keithp.com>
---
 hw/xfree86/common/xf86AutoConfig.c | 88 ++++++++++++++++++++++++++++--
 1 file changed, 82 insertions(+), 6 deletions(-)

diff --git a/hw/xfree86/common/xf86AutoConfig.c b/hw/xfree86/common/xf86AutoConfig.c
index 7f4ada88b..56f7debfb 100644
--- a/hw/xfree86/common/xf86AutoConfig.c
+++ b/hw/xfree86/common/xf86AutoConfig.c
@@ -546,10 +546,41 @@ chooseVideoDriver(void)
     return chosen_driver;
 }
 
+
+/* copy a screen section and enter the desired driver
+ * and insert it at i in the list of screens */
+static Bool
+copyScreen(confScreenPtr oscreen, GDevPtr odev, int i, char *driver)
+{
+    GDevPtr cptr = NULL;
+
+    xf86ConfigLayout.screens[i].screen = xnfcalloc(1, sizeof(confScreenRec));
+    if(!xf86ConfigLayout.screens[i].screen)
+        return FALSE;
+    memcpy(xf86ConfigLayout.screens[i].screen, oscreen, sizeof(confScreenRec));
+
+    cptr = xcalloc(1, sizeof(GDevRec));
+    if (!cptr)
+        return FALSE;
+    memcpy(cptr, odev, sizeof(GDevRec));
+
+    cptr->identifier = Xprintf("Autoconfigured Video Device %s", driver);
+    cptr->driver = driver;
+
+    /* now associate the new driver entry with the new screen entry */
+    xf86ConfigLayout.screens[i].screen->device = cptr;
+    cptr->myScreenSection = xf86ConfigLayout.screens[i].screen;
+
+    return TRUE;
+}
+
 GDevPtr
 autoConfigDevice(GDevPtr preconf_device)
 {
     GDevPtr ptr = NULL;
+    char *matches[20]; /* If we have more than 20 drivers we're in trouble */
+    int num_matches = 0, num_screens = 0, i;
+    screenLayoutPtr slp;
 
     if (!xf86configptr) {
         return NULL;
@@ -573,14 +604,59 @@ autoConfigDevice(GDevPtr preconf_device)
         ptr->driver = NULL;
     }
     if (!ptr->driver) {
-        ptr->driver = chooseVideoDriver();
+        /* get all possible video drivers and count them */
+        listPossibleVideoDrivers(matches, 20);
+        for (; matches[num_matches]; num_matches++) {
+            xf86Msg(X_DEFAULT, "Matched %s as autoconfigured driver %d\n",
+                    matches[num_matches], num_matches);
+        }
+
+        slp = xf86ConfigLayout.screens;
+        if (slp) {
+            /* count the number of screens and make space for
+             * a new screen for each additional possible driver
+             * minus one for the already existing first one
+             * plus one for the terminating NULL */
+            for (; slp[num_screens].screen; num_screens++);
+            xf86ConfigLayout.screens = xnfcalloc(num_screens + num_matches,
+                                                sizeof(screenLayoutRec));
+            xf86ConfigLayout.screens[0] = slp[0];
+
+            /* do the first match and set that for the original first screen */
+            ptr->driver = matches[0];
+            if (!xf86ConfigLayout.screens[0].screen->device) {
+                xf86ConfigLayout.screens[0].screen->device = ptr;
+                ptr->myScreenSection = xf86ConfigLayout.screens[0].screen;
+            }
+
+            /* for each other driver found, copy the first screen, insert it
+             * into the list of screens and set the driver */
+            i = 0;
+            while (i++ < num_matches) {
+                if (!copyScreen(slp[0].screen, ptr, i, matches[i]))
+                    return NULL;
+            }
+
+            /* shift the rest of the original screen list
+             * to the end of the current screen list
+             *
+             * TODO Handle rest of multiple screen sections */
+            for (i = 1; i < num_screens; i++) {
+                xf86ConfigLayout.screens[i+num_matches] = slp[i];
+            }
+            xf86ConfigLayout.screens[num_screens+num_matches-1].screen = NULL;
+            xfree(slp);
+        } else {
+            /* layout does not have any screens, not much to do */
+            ptr->driver = matches[0];
+            for (i = 1; matches[i] ; i++) {
+                if (matches[i] != matches[0]) {
+                    xfree(matches[i]);
+                }
+            }
+        }
     }
 
-    /* TODO Handle multiple screen sections */
-    if (xf86ConfigLayout.screens && !xf86ConfigLayout.screens->screen->device) {
-        xf86ConfigLayout.screens->screen->device = ptr;
-        ptr->myScreenSection = xf86ConfigLayout.screens->screen;
-    }
     xf86Msg(X_DEFAULT, "Assigned the driver to the xf86ConfigLayout\n");
 
     return ptr;