First cut at signal handling support.

* Makefile (OBJS-y): Include signal.o if have_posix_sigs is "y".

* configure (have_posix_sigs): New variable, set by detecting POSIX
signal stuff.

* dep.mk: Regenerated.

* arith.c, debug.c, eval.c, filter.c, hash.c, match.c, parser.y,
parser.l, rand.c, regex.c, syslog.c, txr.c, utf8.c: Include new
signal.h header, now required by unwind, and the <signal.h> system
header.

* eval.c (exit_wrap): New function.
(eval_init): New functions registered as intrinsics: exit_wrap,
set_sig_handler, get_sig_handler, sig_check.

* gc.c (release): Unused functions removed.

* gc.h (release): Declaration removed.

* lib.c (init): Call sig_init.

* stream.c (set_putc, se_getc, se_fflush): New static functions.
(stdio_put_char_callback, stdio_get_char_callback, stdio_put_byte,
stdio_flush, stdio_get_byte): Use new functions to enable
signals when blocked on I/O.
(tail_strategy): Allow signals across sleep.
(pipev_close): Allow signals across waitpid.
(se_pclose): New static function.
(pipe_close): Use new function to enable signals across pclose.

* unwind.c (uw_unwind_to_exit_point): use extended_longjmp instead of
longjmp.

* unwind.h (struct uw_block, struct uw_catch): jb member changes from
jmp_buf to extended_jmp_buf.
(uw_block_begin, uw_simple_catch_begin, uw_catch_begin): Use
extended_setjmp instead of setjmp.

* signal.c: New file.

* signal.h: New file.

1 files changed, 5 insertions, 3 deletions

diff --git a/unwind.c b/unwind.c
index 034303b5..f447bb07 100644
--- a/unwind.c
+++ b/unwind.c
@@ -31,11 +31,13 @@
 #include <setjmp.h>
 #include <dirent.h>
 #include <stdarg.h>
+#include <signal.h>
 #include "config.h"
 #include "lib.h"
 #include "gc.h"
 #include "stream.h"
 #include "txr.h"
+#include "signal.h"
 #include "unwind.h"
 
 static uw_frame_t *uw_stack;
@@ -67,7 +69,7 @@ static void uw_unwind_to_exit_point(void)
       uw_stack->ca.exception = nil;
       uw_stack->ca.cont = uw_exit_point;
       /* 1 means unwind only. */
-      longjmp(uw_stack->ca.jb, 1);
+      extended_longjmp(uw_stack->ca.jb, 1);
       abort();
     case UW_ENV:
       /* Maintain consistency of unwind stack pointer */
@@ -85,13 +87,13 @@ static void uw_unwind_to_exit_point(void)
 
   switch (uw_stack->uw.type) {
   case UW_BLOCK:
-    longjmp(uw_stack->bl.jb, 1);
+    extended_longjmp(uw_stack->bl.jb, 1);
     abort();
   case UW_ENV: /* env frame cannot be exit point */
     abort();
   case UW_CATCH:
     /* 2 means actual catch, not just unwind */
-    longjmp(uw_stack->ca.jb, 2);
+    extended_longjmp(uw_stack->ca.jb, 2);
   default:
     abort();
   }