Parser/intrcheck.c

   1 /***********************************************************
   2 Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam,
   3 The Netherlands.
   4
   5                         All Rights Reserved
   6
   7 Permission to use, copy, modify, and distribute this software and its
   8 documentation for any purpose and without fee is hereby granted,
   9 provided that the above copyright notice appear in all copies and that
  10 both that copyright notice and this permission notice appear in
  11 supporting documentation, and that the names of Stichting Mathematisch
  12 Centrum or CWI or Corporation for National Research Initiatives or
  13 CNRI not be used in advertising or publicity pertaining to
  14 distribution of the software without specific, written prior
  15 permission.
  16
  17 While CWI is the initial source for this software, a modified version
  18 is made available by the Corporation for National Research Initiatives
  19 (CNRI) at the Internet address ftp://ftp.python.org.
  20
  21 STICHTING MATHEMATISCH CENTRUM AND CNRI DISCLAIM ALL WARRANTIES WITH
  22 REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF
  23 MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH
  24 CENTRUM OR CNRI BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
  25 DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  26 PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  27 TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  28 PERFORMANCE OF THIS SOFTWARE.
  29
  30 ******************************************************************/
  31
  32 /* Check for interrupts */
  33
  34 #include "config.h"
  35 #include "myproto.h"
  36 #include "mymalloc.h" /* For ANY */
  37 #include "intrcheck.h"
  38
  39 /* Copied here from ceval.h -- can't include that file. */
  40 int Py_AddPendingCall Py_PROTO((int (*func) Py_PROTO((ANY *)), ANY *arg));
  41
  42
  43 #ifdef QUICKWIN
  44
  45 #include <io.h>
  46
  47 void
  48 PyOS_InitInterrupts()
  49 {
  50 }
  51
  52 void
  53 PyOS_FiniInterrupts()
  54 {
  55 }
  56
  57 int
  58 PyOS_InterruptOccurred()
  59 {
  60         _wyield();
  61 }
  62
  63 #define OK
  64
  65 #endif /* QUICKWIN */
  66
  67 #if defined(_M_IX86) && !defined(__QNX__)
  68 #include <io.h>
  69 #endif
  70
  71 #if defined(MSDOS) && !defined(QUICKWIN)
  72
  73 #ifdef __GNUC__
  74
  75 /* This is for DJGPP's GO32 extender.  I don't know how to trap
  76  * control-C  (There's no API for ctrl-C, and I don't want to mess with
  77  * the interrupt vectors.)  However, this DOES catch control-break.
  78  * --Amrit
  79  */
  80
  81 #include <go32.h>
  82
  83 void
  84 PyOS_InitInterrupts()
  85 {
  86         _go32_want_ctrl_break(1 /* TRUE */);
  87 }
  88
  89 void
  90 PyOS_FiniInterrupts()
  91 {
  92 }
  93
  94 int
  95 PyOS_InterruptOccurred()
  96 {
  97         return _go32_was_ctrl_break_hit();
  98 }
  99
 100 #else /* !__GNUC__ */
 101
 102 /* This might work for MS-DOS (untested though): */
 103
 104 void
 105 PyOS_InitInterrupts()
 106 {
 107 }
 108
 109 void
 110 PyOS_FiniInterrupts()
 111 {
 112 }
 113
 114 int
 115 PyOS_InterruptOccurred()
 116 {
 117         int interrupted = 0;
 118         while (kbhit()) {
 119                 if (getch() == '\003')
 120                         interrupted = 1;
 121         }
 122         return interrupted;
 123 }
 124
 125 #endif /* __GNUC__ */
 126
 127 #define OK
 128
 129 #endif /* MSDOS && !QUICKWIN */
 130
 131
 132 #ifdef macintosh
 133
 134 /* The Mac interrupt code has moved to macglue.c */
 135 #define OK
 136
 137 #endif /* macintosh */
 138
 139
 140 #ifndef OK
 141
 142 /* Default version -- for real operating systems and for Standard C */
 143
 144 #include <stdio.h>
 145 #include <string.h>
 146 #include <signal.h>
 147 #ifdef HAVE_UNISTD_H
 148 #include <unistd.h>
 149 #endif
 150
 151 static int interrupted;
 152
 153 void
 154 PyErr_SetInterrupt()
 155 {
 156         interrupted = 1;
 157 }
 158
 159 extern int PyErr_CheckSignals();
 160
 161 /* ARGSUSED */
 162 static RETSIGTYPE
 163 #if defined(_M_IX86) && !defined(__QNX__)
 164 intcatcher(int sig)     /* So the C compiler shuts up */
 165 #else /* _M_IX86 */
 166 intcatcher(sig)
 167         int sig; /* Not used by required by interface */
 168 #endif /* _M_IX86 */
 169 {
 170         extern void Py_Exit Py_PROTO((int));
 171         static char message[] =
 172 "python: to interrupt a truly hanging Python program, interrupt once more.\n";
 173         switch (interrupted++) {
 174         case 0:
 175                 break;
 176         case 1:
 177                 write(2, message, strlen(message));
 178                 break;
 179         case 2:
 180                 interrupted = 0;
 181                 Py_Exit(1);
 182                 break;
 183         }
 184         signal(SIGINT, intcatcher);
 185         Py_AddPendingCall(PyErr_CheckSignals, NULL);
 186 }
 187
 188 static RETSIGTYPE (*old_siginthandler)() = SIG_DFL;
 189
 190 void
 191 PyOS_InitInterrupts()
 192 {
 193         if ((old_siginthandler = signal(SIGINT, SIG_IGN)) != SIG_IGN)
 194                 signal(SIGINT, intcatcher);
 195 #ifdef HAVE_SIGINTERRUPT
 196         /* This is for SunOS and other modern BSD derivatives.
 197            It means that system calls (like read()) are not restarted
 198            after an interrupt.  This is necessary so interrupting a
 199            read() or readline() call works as expected.
 200            XXX On old BSD (pure 4.2 or older) you may have to do this
 201            differently! */
 202         siginterrupt(SIGINT, 1);
 203 #endif /* HAVE_SIGINTERRUPT */
 204 }
 205
 206 void
 207 PyOS_FiniInterrupts()
 208 {
 209         signal(SIGINT, old_siginthandler);
 210 }
 211
 212 int
 213 PyOS_InterruptOccurred()
 214 {
 215         if (!interrupted)
 216                 return 0;
 217         interrupted = 0;
 218         return 1;
 219 }
 220
 221 #endif /* !OK */
 222
 223 void
 224 PyOS_AfterFork()
 225 {
 226 }