- Do not call VGLEnd() and exit() to terminate the program

  immediately when a signal is caught.  Instead, defer
  program termination until the next call to VGLCheckSwitch().
  Otherwise, the video card may not be restored correctly
  if the signal is seen while inside libvgl functions.

MFC after: 1 week

1 files changed, 15 insertions, 2 deletions

diff --git a/lib/libvgl/main.c b/lib/libvgl/main.c
index 6522230..5da2047 100644
--- a/lib/libvgl/main.c
+++ b/lib/libvgl/main.c
@@ -54,6 +54,7 @@ static int VGLOldMode;
 static size_t VGLBufSize;
 static byte *VGLMem = MAP_FAILED;
 static int VGLSwitchPending;
+static int VGLAbortPending;
 static int VGLOnDisplay;
 static unsigned int VGLCurWindow;
 static int VGLInitDone = 0;
@@ -67,6 +68,8 @@ struct vt_mode smode;
   if (!VGLInitDone)
     return;
   VGLInitDone = 0;
+  VGLSwitchPending = 0;
+  VGLAbortPending = 0;
 
   signal(SIGUSR1, SIG_IGN);
 
@@ -103,8 +106,12 @@ struct vt_mode smode;
 static void 
 VGLAbort()
 {
-  VGLEnd();
-  exit(0);
+  VGLAbortPending = 1;
+  signal(SIGINT, SIG_IGN);
+  signal(SIGTERM, SIG_IGN);
+  signal(SIGSEGV, SIG_IGN);
+  signal(SIGBUS, SIG_IGN);
+  signal(SIGUSR2, SIG_IGN);
 }
 
 static void
@@ -132,9 +139,11 @@ VGLInit(int mode)
   signal(SIGTERM, VGLAbort);
   signal(SIGSEGV, VGLAbort);
   signal(SIGBUS, VGLAbort);
+  signal(SIGUSR2, SIG_IGN);
 
   VGLOnDisplay = 1;
   VGLSwitchPending = 0;
+  VGLAbortPending = 0;
 
   if (ioctl(0, CONS_GET, &VGLOldMode) || ioctl(0, CONS_CURRENT, &adptype))
     return -1;
@@ -322,6 +331,10 @@ VGLInit(int mode)
 void
 VGLCheckSwitch()
 {
+  if (VGLAbortPending) {
+    VGLEnd();
+    exit(0);
+  }
   while (VGLSwitchPending) {
     unsigned int offset;
     unsigned int len;