merge with 1.8.1h

[gnulib.git] / regex.c

diff --git a/regex.c b/regex.c
index 4bb30f7..8b7aecf 100644 (file)
--- a/regex.c
+++ b/regex.c
@@ -26,6 +26,17 @@
 
 #define _GNU_SOURCE
 
+#ifdef HAVE_CONFIG_H
+#if defined (CONFIG_BROKETS)
+/* We use <config.h> instead of "config.h" so that a compilation
+   using -I. -I$srcdir will use ./config.h rather than $srcdir/config.h
+   (which it would do because it found this file in $srcdir).  */
+#include <config.h>
+#else
+#include "config.h"
+#endif
+#endif
+
 /* We need this for `regex.h', and perhaps for the Emacs include files.  */
 #include <sys/types.h>
 
@@ -46,6 +57,14 @@
 
 #else  /* not emacs */
 
+#ifdef STDC_HEADERS
+#include <stdlib.h>
+#else
+char *malloc ();
+char *realloc ();
+#endif
+
+
 /* We used to test for `BSTRING' here, but only GCC and Emacs define
    `BSTRING', as far as I know, and neither of them use this code.  */
 #if HAVE_STRING_H || STDC_HEADERS
@@ -63,14 +82,6 @@
 #include <strings.h>
 #endif
 
-#ifdef STDC_HEADERS
-#include <stdlib.h>
-#else
-char *malloc ();
-char *realloc ();
-#endif
-
-
 /* Define the syntax stuff for \<, \>, etc.  */
 
 /* This must be nonzero for the wordchar and notwordchar pattern
@@ -881,13 +892,22 @@ static const char *re_error_msg[] =
    using the relocating allocator routines, then malloc could cause a
    relocation, which might (if the strings being searched are in the
    ralloc heap) shift the data out from underneath the regexp
-   routines.  */
+   routines.
+
+   Here's another reason to avoid allocation: Emacs insists on
+   processing input from X in a signal handler; processing X input may
+   call malloc; if input arrives while a matching routine is calling
+   malloc, then we're scrod.  But Emacs can't just block input while
+   calling matching routines; then we don't notice interrupts when
+   they come in.  So, Emacs blocks input around all regexp calls
+   except the matching calls, which it leaves unprotected, in the
+   faith that they will not malloc.  */
 
 /* Normally, this is fine.  */
 #define MATCH_MAY_ALLOCATE
 
 /* But under some circumstances, it's not.  */
-#if defined (REL_ALLOC) && defined (C_ALLOCA)
+#if defined (emacs) || (defined (REL_ALLOC) && defined (C_ALLOCA))
 #undef MATCH_MAY_ALLOCATE
 #endif