crypto: provide apr_crypto_memzero, garanteed to not be optimized out by

compilers.



git-svn-id: https://svn.apache.org/repos/asf/apr/apr/trunk@1763665 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 53 insertions, 0 deletions

diff --git a/configure.in b/configure.in
index b7d2750f5..2664b4e13 100644
--- a/configure.in
+++ b/configure.in
@@ -507,6 +507,22 @@ if test "$ap_cv_atomic_builtins" = "yes"; then
     AC_DEFINE(HAVE_ATOMIC_BUILTINS, 1, [Define if compiler provides atomic builtins])
 fi
 
+AC_CACHE_CHECK([whether the compiler handles weak symbols], [ap_cv_weak_symbols],
+[AC_TRY_RUN([
+__attribute__ ((weak))
+int weak_noop(void)
+{
+    return 0;
+}
+int main()
+{
+    return weak_noop();
+}], [ap_cv_weak_symbols=yes], [ap_cv_weak_symbols=no], [ap_cv_weak_symbols=no])])
+
+if test "$ap_cv_weak_symbols" = "yes"; then
+    AC_DEFINE(HAVE_WEAK_SYMBOLS, 1, [Define if compiler handles weak symbols])
+fi
+
 case $host in
     powerpc-405-*)
         # The IBM ppc405cr processor has a bugged stwcx instruction.
@@ -1938,6 +1954,43 @@ AC_SUBST(have_strdup)
 AC_SUBST(have_strstr)
 AC_SUBST(have_memchr)
 
+AC_CACHE_CHECK([for memset_s support], [apr_cv_memset_s],
+[AC_TRY_RUN([
+#ifdef HAVE_STRING_H
+#define __STDC_WANT_LIB_EXT1__ 1
+#include <string.h>
+#endif
+
+int main(int argc, const char **argv)
+{
+    char buf[1] = "1";
+    return memset_s(buf, sizeof buf, 0, sizeof buf) != 0 || *buf != '\0';
+}], [apr_cv_memset_s=yes], [apr_cv_memset_s=no], [apr_cv_memset_s=no])])
+
+if test "$apr_cv_memset_s" = "yes"; then
+   AC_DEFINE([HAVE_MEMSET_S], 1, [Define if memset_s function is supported])
+fi
+
+AC_CACHE_CHECK([for explicit_bzero support], [apr_cv_explicit_bzero],
+[AC_TRY_RUN([
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+#ifdef HAVE_STRINGS_H
+#include <strings.h>
+#endif
+
+int main(int argc, const char **argv)
+{
+    char buf[1] = "1";
+    explicit_bzero(buf, sizeof buf);
+    return *buf != '\0';
+}], [apr_cv_explicit_bzero=yes], [apr_cv_explicit_bzero=no], [apr_cv_explicit_bzero=no])])
+
+if test "$apr_cv_explicit_bzero" = "yes"; then
+   AC_DEFINE([HAVE_EXPLICIT_BZERO], 1, [Define if explicit_bzero function is supported])
+fi
+
 if test "$off_t_strfn" = "apr_strtoi64" && test "$have_int64_strfn" = "1"; then
     off_t_strfn=$int64_strfn
 fi