svn commit: r345698 - head/lib/libvgl

[Bruce Evans]

Author: bde
Date: Fri Mar 29 16:30:19 2019
New Revision: 345698
URL: https://svnweb.freebsd.org/changeset/base/345698

Log:
  Fix restoring to graphics modes in VGLEnd().
  
  Correct restoring was only attempted for mode 258 (800x600x4 P).  (This
  was the only useful graphics mode supported in the kernel until 10-15
  years ago, and is still the only one explicitly documented in the man
  page).  The comment says that it is the geometry (subscreen size) that
  is restored, but it seems to only be necessary to restore the font
  size, with the geometry only needed since it is set by the same ioctl.
  The font size was not restored for this mode, but was forced to 16.
  
  For other graphics modes, the font size was clobbered to 0.  This
  confuses but doesn't crash the kernel (font size 0 gives null text).
  This confuses and crashes vidcontrol.  The only way to recover was to
  use vidcontrol to set the mode to any text mode on the way back to the
  original graphics mode.
  
  vidcontrol gets this wrong in the opposite way when backing out of
  changes after an error.  It restores the font size correctly, but
  forces the geometry to the full screen size.

Modified:
  head/lib/libvgl/main.c

Modified: head/lib/libvgl/main.c
==============================================================================
--- head/lib/libvgl/main.c	Fri Mar 29 16:05:30 2019	(r345697)
+++ head/lib/libvgl/main.c	Fri Mar 29 16:30:19 2019	(r345698)
@@ -61,12 +61,14 @@ static int VGLAbortPending;
 static int VGLOnDisplay;
 static unsigned int VGLCurWindow;
 static int VGLInitDone = 0;
+static video_info_t VGLOldModeInfo;
 static vid_info_t VGLOldVInfo;
 
 void
 VGLEnd()
 {
 struct vt_mode smode;
+  int size[3];
 
   if (!VGLInitDone)
     return;
@@ -81,18 +83,15 @@ struct vt_mode smode;
     munmap(VGLMem, VGLAdpInfo.va_window_size);
   }
 
-  if (VGLOldMode >= M_VESA_BASE) {
-    /* ugly, but necessary */
+  if (VGLOldMode >= M_VESA_BASE)
     ioctl(0, _IO('V', VGLOldMode - M_VESA_BASE), 0);
-    if (VGLOldMode == M_VESA_800x600) {
-      int size[3];
-      size[0] = VGLOldVInfo.mv_csz;
-      size[1] = VGLOldVInfo.mv_rsz;
-      size[2] = 16;
-      ioctl(0, KDRASTER, size);
-    }
-  } else {
+  else
     ioctl(0, _IO('S', VGLOldMode), 0);
+  if (VGLOldModeInfo.vi_flags & V_INFO_GRAPHICS) {
+    size[0] = VGLOldVInfo.mv_csz;
+    size[1] = VGLOldVInfo.mv_rsz;
+    size[2] = VGLOldVInfo.font_size;;
+    ioctl(0, KDRASTER, size);
   }
   ioctl(0, KDDISABIO, 0);
   ioctl(0, KDSETMODE, KD_TEXT);
@@ -165,12 +164,13 @@ VGLInit(int mode)
   if (ioctl(0, CONS_MODEINFO, &VGLModeInfo))	/* FBIO_MODEINFO */
     return -1;
 
-  /* If current mode is VESA_800x600 then save its geometry to restore later */
-  if ((VGLOldMode >= M_VESA_BASE) && (VGLOldMode == M_VESA_800x600)) {
-    VGLOldVInfo.size = sizeof(VGLOldVInfo);
-    if (ioctl(0, CONS_GETINFO, &VGLOldVInfo))
-      return -1;
-  }
+  /* Save info for old mode to restore font size if old mode is graphics. */
+  VGLOldModeInfo.vi_mode = VGLOldMode;
+  if (ioctl(0, CONS_MODEINFO, &VGLOldModeInfo))
+    return -1;
+  VGLOldVInfo.size = sizeof(VGLOldVInfo);
+  if (ioctl(0, CONS_GETINFO, &VGLOldVInfo))
+    return -1;
 
   VGLDisplay = (VGLBitmap *)malloc(sizeof(VGLBitmap));
   if (VGLDisplay == NULL)