From edcab9553f3ca8c07e271f14318802a1087e2b5a Mon Sep 17 00:00:00 2001
From: mmdolze <mmdolze@users.sourceforge.net>
Date: Sat, 12 Mar 2011 22:36:48 +0000
Subject: [PATCH] Don't use ac_check_headers with the action to add driver to
 the list if checking more than one header. It makes the driver appear several
 times in the list of drivers to build. The driver will be built but fails to
 install then (reported by D. Dumont). Use a nested way to check for headers
 instead.

---
 ChangeLog    |  1 +
 acinclude.m4 | 19 ++++++++++++-------
 2 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 2bd5665..1859c55 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -28,6 +28,7 @@ v.0.5dev (ongoing development)
  * t6963: Convert font to 8 byte bitmap
  * convert i2500vfd and mdm166a driver to use 8 byte bitmap custom character
  * ula200: convert custom characters to 8 byte bitmap
+ * Build system: Fix trying to install svga driver twice
 
 v0.5.4
  * Update driver includes and LDFLAGS (fixed glk and bayrad binding error)
diff --git a/acinclude.m4 b/acinclude.m4
index ef57a68..aedbb87 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -426,18 +426,23 @@ dnl			else
 			actdrivers=["$actdrivers SureElec"]
 			;;
 		svga)
-			AC_CHECK_HEADERS([vga.h vgagl.h],[
-				AC_CHECK_LIB(vga, main,[
-					LIBSVGA="-lvga -lvgagl"
-					DRIVERS="$DRIVERS svga${SO}"
-					actdrivers=["$actdrivers svga"]
+			AC_CHECK_HEADER([vga.h], [
+				AC_CHECK_HEADER([vgagl.h],[
+					AC_CHECK_LIB(vga, main,[
+						LIBSVGA="-lvga -lvgagl"
+						DRIVERS="$DRIVERS svga${SO}"
+						actdrivers=["$actdrivers svga"]
+					],[
+dnl					else
+						AC_MSG_WARN([The svga driver needs the vga library])
+					])
 				],[
 dnl				else
-					AC_MSG_WARN([The svga driver needs the vga library])
+					AC_MSG_WARN([The svga driver needs vgagl.h])
 				])
 			],[
 dnl			else
-				AC_MSG_WARN([The svga driver needs vga.h and vgagl.h])
+				AC_MSG_WARN([The svga driver needs vga.h])
 			])
 			;;
 		t6963)