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, 26 insertions, 0 deletions

diff --git a/eval.c b/eval.c
index cd40a888..f30e895f 100644
--- a/eval.c
+++ b/eval.c
@@ -32,6 +32,7 @@
 #include <setjmp.h>
 #include <stdarg.h>
 #include <wchar.h>
+#include <signal.h>
 #include "config.h"
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
@@ -41,6 +42,7 @@
 #endif
 #include "lib.h"
 #include "gc.h"
+#include "signal.h"
 #include "unwind.h"
 #include "regex.h"
 #include "stream.h"
@@ -2095,6 +2097,22 @@ static val daemon_wrap(val nochdir, val noclose)
 }
 #endif
 
+static val exit_wrap(val status)
+{
+  int stat;
+
+  if (status == nil)
+    stat = EXIT_FAILURE;
+  else if (status == t)
+    stat = EXIT_SUCCESS;
+  else
+    stat = c_num(status);
+
+  exit(stat);
+  /* notreached */
+  return nil;
+}
+
 static void reg_fun(val sym, val fun)
 {
   sethash(top_fb, sym, cons(sym, fun));
@@ -2591,6 +2609,8 @@ void eval_init(void)
   reg_fun(intern(lit("make-time-utc"), user_package), func_n7(make_time_utc));
 
   reg_fun(intern(lit("errno"), user_package), func_n1o(errno_wrap, 0));
+  reg_fun(intern(lit("exit"), user_package), func_n1(exit_wrap));
+
 #if HAVE_DAEMON
   reg_fun(intern(lit("daemon"), user_package), func_n2(daemon_wrap));
 #endif
@@ -2624,6 +2644,12 @@ void eval_init(void)
   reg_fun(intern(lit("syslog"), user_package), func_n2v(syslog_wrap));
 #endif
 
+#if HAVE_POSIX_SIGS
+  reg_fun(intern(lit("set-sig-handler"), user_package), func_n2(set_sig_handler));
+  reg_fun(intern(lit("get-sig-handler"), user_package), func_n1(get_sig_handler));
+  reg_fun(intern(lit("sig-check"), user_package), func_n0(sig_check));
+#endif
+
   reg_fun(intern(lit("source-loc"), user_package), func_n1(source_loc));
   reg_fun(intern(lit("source-loc-str"), user_package), func_n1(source_loc_str));