1 files changed, 73 insertions, 0 deletions
diff --git a/m4/strtok_r.m4 b/m4/strtok_r.m4
new file mode 100644
index 0000000..b777089
--- /dev/null
+++ b/m4/strtok_r.m4
@@ -0,0 +1,73 @@
+# strtok_r.m4 serial 15
+dnl Copyright (C) 2002-2004, 2006-2007, 2009-2018 Free Software Foundation,
+dnl Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_FUNC_STRTOK_R],
+[
+  dnl The strtok_r() declaration in lib/string.in.h uses 'restrict'.
+  AC_REQUIRE([AC_C_RESTRICT])
+
+  AC_REQUIRE([gl_HEADER_STRING_H_DEFAULTS])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+  AC_CHECK_FUNCS([strtok_r])
+  if test $ac_cv_func_strtok_r = yes; then
+    HAVE_STRTOK_R=1
+    dnl glibc 2.7 has a bug in strtok_r that causes a segmentation fault
+    dnl when the second argument to strtok_r is a constant string that has
+    dnl exactly one byte and compiling with optimization.  This bug is, for
+    dnl example, present in the glibc 2.7-18 package in Debian "lenny".
+    dnl See <https://sourceware.org/bugzilla/show_bug.cgi?id=5614>.
+    AC_CACHE_CHECK([whether strtok_r works], [gl_cv_func_strtok_r_works],
+      [AC_RUN_IFELSE(
+         [AC_LANG_PROGRAM([[
+              #ifndef __OPTIMIZE__
+              # define __OPTIMIZE__ 1
+              #endif
+              #undef __OPTIMIZE_SIZE__
+              #undef __NO_INLINE__
+              #include <stdlib.h>
+              #include <string.h>
+            ]],
+            [[static const char dummy[] = "\177\01a";
+              char delimiters[] = "xxxxxxxx";
+              char *save_ptr = (char *) dummy;
+              strtok_r (delimiters, "x", &save_ptr);
+              strtok_r (NULL, "x", &save_ptr);
+              return 0;
+            ]])
+         ],
+         [gl_cv_func_strtok_r_works=yes],
+         [gl_cv_func_strtok_r_works=no],
+         [case "$host_os" in
+                           # Guess no on glibc systems.
+            *-gnu* | gnu*) gl_cv_func_strtok_r_works="guessing no" ;;
+                           # Guess yes on native Windows.
+            mingw*)        gl_cv_func_strtok_r_works="guessing yes" ;;
+            *)             gl_cv_func_strtok_r_works="guessing yes" ;;
+          esac
+         ])
+      ])
+    case "$gl_cv_func_strtok_r_works" in
+      *no)
+        dnl We could set REPLACE_STRTOK_R=1 here, but it's only the macro
+        dnl version in <bits/string2.h> which is wrong. The code compiled
+        dnl into libc is fine.
+        UNDEFINE_STRTOK_R=1
+        ;;
+    esac
+  else
+    HAVE_STRTOK_R=0
+  fi
+  AC_CHECK_DECLS_ONCE([strtok_r])
+  if test $ac_cv_have_decl_strtok_r = no; then
+    HAVE_DECL_STRTOK_R=0
+  fi
+])
+
+# Prerequisites of lib/strtok_r.c.
+AC_DEFUN([gl_PREREQ_STRTOK_R], [
+  :
+])