X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Fc-stack.m4;h=8049d96bdfdcf8ab6d9efd53c16aa2501ab4c2b4;hb=cb0ff6fd5914e7b0e9272324422fe7c725bfd5a0;hp=01c9a884c23f8bd36ae493a7cc2c1a8718303f2e;hpb=a55efbd0d21a7d9f5ccb338120cd5e29bcff9a0a;p=gnulib.git

diff --git a/m4/c-stack.m4 b/m4/c-stack.m4
index 01c9a884c..8049d96bd 100644
--- a/m4/c-stack.m4
+++ b/m4/c-stack.m4
@@ -1,6 +1,6 @@
 # Check prerequisites for compiling lib/c-stack.c.
 
-# Copyright (C) 2002 Free Software Foundation, Inc.
+# Copyright (C) 2002, 2003 Free Software Foundation, Inc.
 
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -22,13 +22,20 @@
 AC_DEFUN([AC_SYS_XSI_STACK_OVERFLOW_HEURISTIC],
   [# for STACK_DIRECTION
    AC_REQUIRE([AC_FUNC_ALLOCA])
+   AC_CHECK_FUNCS(setrlimit)
 
    AC_CACHE_CHECK([for working C stack overflow detection],
      ac_cv_sys_xsi_stack_overflow_heuristic,
      [AC_TRY_RUN(
 	[
+	 #include <unistd.h>
 	 #include <signal.h>
 	 #include <ucontext.h>
+	 #if HAVE_SETRLIMIT
+	 # include <sys/types.h>
+	 # include <sys/time.h>
+	 # include <sys/resource.h>
+	 #endif
 
 	 static union
 	 {
@@ -101,6 +108,16 @@ AC_DEFUN([AC_SYS_XSI_STACK_OVERFLOW_HEURISTIC],
 	 int
 	 main (void)
 	 {
+	   #if HAVE_SETRLIMIT && defined RLIMIT_STACK
+	   /* Before starting the endless recursion, try to be friendly
+	      to the user's machine.  On some Linux 2.2.x systems, there
+	      is no stack limit for user processes at all.  We don't want
+	      to kill such systems.  */
+	   struct rlimit rl;
+	   rl.rlim_cur = rl.rlim_max = 0x100000; /* 1 MB */
+	   setrlimit (RLIMIT_STACK, &rl);
+	   #endif
+
 	   c_stack_action ();
 	   return recurse ("\1");
 	 }
@@ -131,6 +148,13 @@ AC_DEFUN([jm_PREREQ_C_STACK],
    AC_CHECK_DECLS([getcontext], , , [#include <ucontext.h>])
    AC_CHECK_DECLS([sigaltstack], , , [#include <signal.h>])
 
-   AC_CHECK_HEADERS(sys/resource.h ucontext.h unistd.h)
+   AC_CHECK_HEADERS_ONCE(sys/time.h unistd.h)
+   AC_CHECK_HEADERS(sys/resource.h ucontext.h)
 
    AC_CHECK_TYPES([stack_t], , , [#include <signal.h>])])
+
+AC_DEFUN([gl_C_STACK],
+[
+  dnl Prerequisites of lib/c-stack.c.
+  jm_PREREQ_C_STACK
+])