From 010d5fba9324173f74ec6630acb971c26fe34fe1 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <icculus@icculus.org>
Date: Mon, 26 Oct 2020 09:49:09 -0400
Subject: [PATCH] kmsdrm: Make this build with significantly older system
 libraries.

This allows one to build Raspberry Pi versions on an ancient version of
Raspbian and get both the KMSDRM and RPI video targets built into SDL, giving
maximum binary compatibility from linking against an older glibc, etc, but
also making one library that can access video on all RPi models and OS
releases.
---
 configure                          | 32 +++++++++++++++---------------
 configure.ac                       |  4 ++--
 src/video/kmsdrm/SDL_kmsdrmvideo.c |  8 ++++++++
 3 files changed, 26 insertions(+), 18 deletions(-)

diff --git a/configure b/configure
index 5ad03f2ec..d52252133 100755
--- a/configure
+++ b/configure
@@ -21987,12 +21987,12 @@ if test -n "$LIBDRM_CFLAGS"; then
     pkg_cv_LIBDRM_CFLAGS="$LIBDRM_CFLAGS"
  elif test -n "$PKG_CONFIG"; then
     if test -n "$PKG_CONFIG" && \
-    { { $as_echo "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"libdrm >= 2.4.82\""; } >&5
-  ($PKG_CONFIG --exists --print-errors "libdrm >= 2.4.82") 2>&5
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"libdrm >= 1.4.82\""; } >&5
+  ($PKG_CONFIG --exists --print-errors "libdrm >= 1.4.82") 2>&5
   ac_status=$?
   $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
-  pkg_cv_LIBDRM_CFLAGS=`$PKG_CONFIG --cflags "libdrm >= 2.4.82" 2>/dev/null`
+  pkg_cv_LIBDRM_CFLAGS=`$PKG_CONFIG --cflags "libdrm >= 1.4.82" 2>/dev/null`
 else
   pkg_failed=yes
 fi
@@ -22003,12 +22003,12 @@ if test -n "$LIBDRM_LIBS"; then
     pkg_cv_LIBDRM_LIBS="$LIBDRM_LIBS"
  elif test -n "$PKG_CONFIG"; then
     if test -n "$PKG_CONFIG" && \
-    { { $as_echo "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"libdrm >= 2.4.82\""; } >&5
-  ($PKG_CONFIG --exists --print-errors "libdrm >= 2.4.82") 2>&5
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"libdrm >= 1.4.82\""; } >&5
+  ($PKG_CONFIG --exists --print-errors "libdrm >= 1.4.82") 2>&5
   ac_status=$?
   $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
-  pkg_cv_LIBDRM_LIBS=`$PKG_CONFIG --libs "libdrm >= 2.4.82" 2>/dev/null`
+  pkg_cv_LIBDRM_LIBS=`$PKG_CONFIG --libs "libdrm >= 1.4.82" 2>/dev/null`
 else
   pkg_failed=yes
 fi
@@ -22028,9 +22028,9 @@ else
         _pkg_short_errors_supported=no
 fi
         if test $_pkg_short_errors_supported = yes; then
-	        LIBDRM_PKG_ERRORS=`$PKG_CONFIG --short-errors --print-errors "libdrm >= 2.4.82" 2>&1`
+	        LIBDRM_PKG_ERRORS=`$PKG_CONFIG --short-errors --print-errors "libdrm >= 1.4.82" 2>&1`
         else
-	        LIBDRM_PKG_ERRORS=`$PKG_CONFIG --print-errors "libdrm >= 2.4.82" 2>&1`
+	        LIBDRM_PKG_ERRORS=`$PKG_CONFIG --print-errors "libdrm >= 1.4.82" 2>&1`
         fi
 	# Put the nasty error message in config.log where it belongs
 	echo "$LIBDRM_PKG_ERRORS" >&5
@@ -22056,12 +22056,12 @@ if test -n "$LIBGBM_CFLAGS"; then
     pkg_cv_LIBGBM_CFLAGS="$LIBGBM_CFLAGS"
  elif test -n "$PKG_CONFIG"; then
     if test -n "$PKG_CONFIG" && \
-    { { $as_echo "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"gbm >= 17.1.0\""; } >&5
-  ($PKG_CONFIG --exists --print-errors "gbm >= 17.1.0") 2>&5
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"gbm >= 11.1.0\""; } >&5
+  ($PKG_CONFIG --exists --print-errors "gbm >= 11.1.0") 2>&5
   ac_status=$?
   $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
-  pkg_cv_LIBGBM_CFLAGS=`$PKG_CONFIG --cflags "gbm >= 17.1.0" 2>/dev/null`
+  pkg_cv_LIBGBM_CFLAGS=`$PKG_CONFIG --cflags "gbm >= 11.1.0" 2>/dev/null`
 else
   pkg_failed=yes
 fi
@@ -22072,12 +22072,12 @@ if test -n "$LIBGBM_LIBS"; then
     pkg_cv_LIBGBM_LIBS="$LIBGBM_LIBS"
  elif test -n "$PKG_CONFIG"; then
     if test -n "$PKG_CONFIG" && \
-    { { $as_echo "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"gbm >= 17.1.0\""; } >&5
-  ($PKG_CONFIG --exists --print-errors "gbm >= 17.1.0") 2>&5
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"gbm >= 11.1.0\""; } >&5
+  ($PKG_CONFIG --exists --print-errors "gbm >= 11.1.0") 2>&5
   ac_status=$?
   $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
-  pkg_cv_LIBGBM_LIBS=`$PKG_CONFIG --libs "gbm >= 17.1.0" 2>/dev/null`
+  pkg_cv_LIBGBM_LIBS=`$PKG_CONFIG --libs "gbm >= 11.1.0" 2>/dev/null`
 else
   pkg_failed=yes
 fi
@@ -22097,9 +22097,9 @@ else
         _pkg_short_errors_supported=no
 fi
         if test $_pkg_short_errors_supported = yes; then
-	        LIBGBM_PKG_ERRORS=`$PKG_CONFIG --short-errors --print-errors "gbm >= 17.1.0" 2>&1`
+	        LIBGBM_PKG_ERRORS=`$PKG_CONFIG --short-errors --print-errors "gbm >= 11.1.0" 2>&1`
         else
-	        LIBGBM_PKG_ERRORS=`$PKG_CONFIG --print-errors "gbm >= 17.1.0" 2>&1`
+	        LIBGBM_PKG_ERRORS=`$PKG_CONFIG --print-errors "gbm >= 11.1.0" 2>&1`
         fi
 	# Put the nasty error message in config.log where it belongs
 	echo "$LIBGBM_PKG_ERRORS" >&5
diff --git a/configure.ac b/configure.ac
index 52a5dc340..c9c0295ec 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2246,8 +2246,8 @@ AS_HELP_STRING([--enable-video-kmsdrm], [use KMSDRM video driver [[default=no]]]
     if test x$enable_video = xyes -a x$enable_video_kmsdrm = xyes; then
         video_kmsdrm=no
 
-        PKG_CHECK_MODULES([LIBDRM], [libdrm >= 2.4.82], libdrm_avail=yes, libdrm_avail=no)
-        PKG_CHECK_MODULES([LIBGBM], [gbm >= 17.1.0], libgbm_avail=yes, libgbm_avail=no)
+        PKG_CHECK_MODULES([LIBDRM], [libdrm >= 1.4.82], libdrm_avail=yes, libdrm_avail=no)
+        PKG_CHECK_MODULES([LIBGBM], [gbm >= 11.1.0], libgbm_avail=yes, libgbm_avail=no)
 
         if test x$libdrm_avail = xyes -a x$libgbm_avail = xyes; then
             video_kmsdrm=yes
diff --git a/src/video/kmsdrm/SDL_kmsdrmvideo.c b/src/video/kmsdrm/SDL_kmsdrmvideo.c
index 86e8dba16..da2defe06 100644
--- a/src/video/kmsdrm/SDL_kmsdrmvideo.c
+++ b/src/video/kmsdrm/SDL_kmsdrmvideo.c
@@ -46,6 +46,14 @@
 #include <errno.h>
 #include <poll.h>
 
+/* for older KMSDRM headers... */
+#ifndef DRM_FORMAT_MOD_VENDOR_NONE
+#define DRM_FORMAT_MOD_VENDOR_NONE 0
+#endif
+#ifndef DRM_FORMAT_MOD_LINEAR
+#define DRM_FORMAT_MOD_LINEAR fourcc_mod_code(NONE, 0)
+#endif
+
 #define KMSDRM_DRI_PATH "/dev/dri/"
 
 #define AMDGPU_COMPAT 1