From efd998524fd25beffb8187853580d164da46b70b Mon Sep 17 00:00:00 2001
From: vsc <vsc@b08c6af1-5177-4d33-ba66-4b1c6b8b522a>
Date: Wed, 27 Jun 2001 13:22:30 +0000
Subject: [PATCH] More interrupt handling cleanups!

git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@104 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
---
 C/absmi.c       | 14 ++++++++----
 C/errors.c      |  1 +
 C/init.c        |  3 ++-
 C/iopreds.c     | 21 ++++++++----------
 C/sysbits.c     | 32 ++++++++++++++-------------
 changes4.3.html |  5 +++++
 m4/Yap.h.m4     | 59 +++++++++++++++++++++++++++++++++++++------------
 7 files changed, 89 insertions(+), 46 deletions(-)

diff --git a/C/absmi.c b/C/absmi.c
index 395ce2de7..8b95cf8b5 100644
--- a/C/absmi.c
+++ b/C/absmi.c
@@ -1977,7 +1977,7 @@ absmi(int inp)
        * *cannot* fail before having woken up all suspended goals.
        */
       /* make sure we are here because of an awoken goal */
-      if (CFREG == Unsigned(LCL0) && !(PrologMode & AbortMode)) {
+      if (CFREG == Unsigned(LCL0) && !(PrologMode & (InterruptMode|AbortMode))) {
 	Term WGs;
 	Term my_goal;
 
@@ -2051,11 +2051,17 @@ absmi(int inp)
       }
       else {
 #endif
-	if (PrologMode & AbortMode) {
-	  PrologMode &= ~AbortMode;
+	if (PrologMode & (AbortMode|InterruptMode)) {
 	  CFREG = CalculateStackGap();
 	  /* same instruction */
-	  if (ProcessSIGINT() < 0) Abort("");
+	  if (PrologMode & InterruptMode) {
+	    PrologMode &= ~InterruptMode;
+	    ProcessSIGINT();
+	  } 
+	  if (PrologMode & AbortMode) {
+	    PrologMode &= ~AbortMode;
+	    Abort("");
+	  }
 	  JMPNext();
 	}
 #if SHADOW_S
diff --git a/C/errors.c b/C/errors.c
index b652eb772..477d95659 100644
--- a/C/errors.c
+++ b/C/errors.c
@@ -211,6 +211,7 @@ Abort (char *format,...)
   va_list ap;
   va_start (ap, format);
 
+  PrologMode &= ~AbortMode;
   if (format)
     {
       char ch;
diff --git a/C/init.c b/C/init.c
index bc64c3a60..4f2b05592 100644
--- a/C/init.c
+++ b/C/init.c
@@ -138,7 +138,8 @@ char FileNameBuf[YAP_FILENAME_MAX], FileNameBuf2[YAP_FILENAME_MAX];
 
 /********* Prolog State ********************************************/
 
-int             PrologMode = BootMode;
+prolog_exec_mode      PrologMode = BootMode;
+int      CritLocks = 0;
 
 #if PUSH_REGS
 REGSTORE standard_regs;
diff --git a/C/iopreds.c b/C/iopreds.c
index af3dc742a..7323340fa 100644
--- a/C/iopreds.c
+++ b/C/iopreds.c
@@ -1196,26 +1196,23 @@ ConsoleGetc(int sno)
     strncpy (Prompt, RepAtom (*AtPrompt)->StrOfAE, MAX_PROMPT);
     newline = FALSE;
   }
-  in_getc = TRUE;
 #if HAVE_SIGINTERRUPT
   siginterrupt(SIGINT, TRUE);
 #endif
+  in_getc = TRUE;
   ch = YP_fgetc(s->u.file.file);
+  in_getc = FALSE;
 #if HAVE_SIGINTERRUPT
   siginterrupt(SIGINT, FALSE);
 #endif
-  in_getc = FALSE;
-  if (PrologMode & AbortMode) {
-    PrologMode &= ~AbortMode;
-    CreepFlag = CalculateStackGap();
-    if (ProcessSIGINT() < 0) Abort("");
-    newline = TRUE;
-    goto restart;
-  } else if (ch == -1 && errno == EINTR) {
-    errno = 0;
-    PrologMode &= ~AbortMode;
-    if (ProcessSIGINT() < 0) Abort("");
+  if (PrologMode & InterruptMode) {
+    PrologMode &= ~InterruptMode;
+    ProcessSIGINT();
     newline = TRUE;
+    if (PrologMode & AbortMode) {
+      PrologMode &= ~AbortMode;
+      Abort("");
+    }
     goto restart;
   }
   return(console_post_process_read_char(ch, s, sno));
diff --git a/C/sysbits.c b/C/sysbits.c
index 5697192a2..b5b5f40de 100644
--- a/C/sysbits.c
+++ b/C/sysbits.c
@@ -1076,7 +1076,7 @@ InteractSIGINT(char ch) {
     /* we can't do a direct abort, so ask the system to do
        it for us */
     p_creep();
-    PutValue(AtomThrow, MkAtomTerm(AtomTrue));
+    PrologMode |= AbortMode;
     return(-1);
   case 'c':
     /* continue */
@@ -1177,16 +1177,6 @@ ProcessSIGINT(void)
 {
   int ch, out;
 
-#if HAVE_ISATTY
-  if (!isatty(0)) {
-    InteractSIGINT('e');
-  }
-#if !HAVE_LIBREADLINE
-  if (in_getc) {
-    return(0);
-  }
-#endif
-#endif
   do {
 #if  HAVE_LIBREADLINE
     if (_line != (char *) NULL && _line != (char *) EOF)
@@ -1227,10 +1217,22 @@ HandleSIGINT (int sig)
 #endif
 {
   my_signal(SIGINT, HandleSIGINT);
-#if (_MSC_VER || defined(__MINGW32__))
-  printf("hello\n");
-  return;
+#if HAVE_ISATTY
+  if (!isatty(0)) {
+    InteractSIGINT('e');
+  }
 #endif
+#if !HAVE_LIBREADLINE
+  if (in_getc) {
+    PrologMode |= InterruptMode;
+    return;
+  }
+#endif
+  if (PrologMode & CritMode) {
+    /* delay processing if we are messing with the Code space */
+    PrologMode |= InterruptMode;
+    return;
+  }
 #ifdef HAVE_SETBUF
   /* make sure we are not waiting for the end of line */
   YP_setbuf (stdin, NULL); 
@@ -1301,7 +1303,7 @@ MSCHandleSignal(DWORD dwCtrlType) {
   case CTRL_C_EVENT:
   case CTRL_BREAK_EVENT:
     p_creep();
-    PrologMode |= AbortMode;
+    PrologMode |= InterruptMode;
     return(TRUE);
   default:
     return(FALSE);
diff --git a/changes4.3.html b/changes4.3.html
index a794462f5..919f3f21f 100644
--- a/changes4.3.html
+++ b/changes4.3.html
@@ -16,6 +16,11 @@
 
 <h2>Yap-4.3.19:</h2>
 <ul>
+	<li>FIXED: make ^c-a work within gc.</li>
+	<li>FIXED: handle correctly very deep nested terms while gc
+	marking.</li>
+	<li>FIXED: ArityOfFunctor was giving trouble with HP-UX cc
+	(Stasinos Konstantinos).</li>
 	<li>FIXED: ^c works with Yap/MINGW32 (not in cygwin).</li>
 	<li>FIXED: ^c a should never core dump.</li>
 	<li>FIXED: comparison of variables in sub-terms.</li>
diff --git a/m4/Yap.h.m4 b/m4/Yap.h.m4
index 75491dc34..aa5670b39 100644
--- a/m4/Yap.h.m4
+++ b/m4/Yap.h.m4
@@ -10,7 +10,7 @@
 * File:		Yap.h.m4						 *
 * mods:									 *
 * comments:	main header file for YAP				 *
-* version:      $Id: Yap.h.m4,v 1.5 2001-06-22 17:53:36 vsc Exp $	 *
+* version:      $Id: Yap.h.m4,v 1.6 2001-06-27 13:22:30 vsc Exp $	 *
 *************************************************************************/
 
 #include "config.h"
@@ -754,14 +754,16 @@ extern int      CurFileNo;
 
 /********* Prolog may be in several modes *******************************/
 
-#define BootMode       1		/* if booting or restoring */
-#define UserMode       2		/* Normal mode */
-#define CritMode       4		/* If we are meddling with the heap */
-#define FullLMode      8		/* to access the hidden atoms chain */
-#define AbortMode     16		/* expecting to abort */
-#define InterruptMode 32		/* under an interrupt */
+typedef enum {
+  BootMode  =   1,		/* if booting or restoring */
+  UserMode  =   2,		/* Normal mode */
+  CritMode  =   4,		/* If we are meddling with the heap */
+  AbortMode =   8,		/* expecting to abort */
+  InterruptMode = 16		/* under an interrupt */
+} prolog_exec_mode;
 
-extern int      PrologMode;
+extern prolog_exec_mode      PrologMode;
+extern int      CritLocks;
 
 #if SIZEOF_INT_P==4
 #if defined(YAPOR) || defined(TABLING)
@@ -802,17 +804,46 @@ extern int      yap_argc;
 	    GLOBAL_LOCKS_who_locked_heap = worker_id;       \
 	  }                                                 \
           PrologMode |= CritMode;                           \
+          CritLocks++;                                      \
         }
 #define YAPLeaveCriticalSection()                                        \
 	{                                                                \
-          if ((PrologMode ^= CritMode) & AbortMode) Abort((char *)NIL);  \
-	  GLOBAL_LOCKS_who_locked_heap = MAX_WORKERS;                    \
-          UNLOCK(GLOBAL_LOCKS_heap_access);                              \
+          CritLocks--;                                                   \
+          if (!CritLocks) {                                              \
+            PrologMode &= ~CritMode;                                     \
+            if (PrologMode & InterruptMode) {                            \
+	      PrologMode &= ~InterruptMode;                              \
+	      ProcessSIGINT();                                           \
+            }                                                            \
+            if (PrologMode & AbortMode) {                                \
+	      PrologMode &= ~AbortMode;                                  \
+	      Abort("");                                                 \
+            }                                                            \
+	    GLOBAL_LOCKS_who_locked_heap = MAX_WORKERS;                  \
+            UNLOCK(GLOBAL_LOCKS_heap_access);                            \
+          }                                                              \
         }
 #else
-#define YAPEnterCriticalSection()     PrologMode |= CritMode;
-#define YAPLeaveCriticalSection() \
-	if((PrologMode ^= CritMode) & AbortMode) Abort((char *)NIL);
+#define YAPEnterCriticalSection()                           \
+	{                                                   \
+          PrologMode |= CritMode;                           \
+          CritLocks++;                                      \
+        }
+#define YAPLeaveCriticalSection()                                        \
+	{                                                                \
+          CritLocks--;                                                   \
+          if (!CritLocks) {                                              \
+            PrologMode &= ~CritMode;                                     \
+            if (PrologMode & InterruptMode) {                            \
+	      PrologMode &= ~InterruptMode;                              \
+	      ProcessSIGINT();                                           \
+            }                                                            \
+            if (PrologMode & AbortMode) {                                \
+	      PrologMode &= ~AbortMode;                                  \
+	      Abort("");                                                 \
+            }                                                            \
+          }                                                              \
+        }
 #endif /* YAPOR */
 
 /* when we are calling the InitStaff procedures */