Add test for FREAD_READS_DIRECTORIES to detect when fread() reads fopen'ed
directory.
Signed-off-by: Michal Rokos <michal.rokos@nextsoft.cz>
Tested-by: Mike Ralphson <mike@abacus.co.uk>
diff --git a/config.mak.in b/config.mak.in
index 8e1cd5f..7868dfd 100644
--- a/config.mak.in
+++ b/config.mak.in
@@ -46,4 +46,5 @@ NO_MKDTEMP=@NO_MKDTEMP@
NO_ICONV=@NO_ICONV@
OLD_ICONV=@OLD_ICONV@
NO_DEFLATE_BOUND=@NO_DEFLATE_BOUND@
+FREAD_READS_DIRECTORIES=@FREAD_READS_DIRECTORIES@
SNPRINTF_RETURNS_BOGUS=@SNPRINTF_RETURNS_BOGUS@
diff --git a/configure.ac b/configure.ac
index 287149d..82584e9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -327,6 +327,26 @@ else
fi
AC_SUBST(NO_C99_FORMAT)
#
+# Define FREAD_READS_DIRECTORIES if your are on a system which succeeds
+# when attempting to read from an fopen'ed directory.
+AC_CACHE_CHECK([whether system succeeds to read fopen'ed directory],
+ [ac_cv_fread_reads_directories],
+[
+AC_RUN_IFELSE(
+ [AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT],
+ [[char c;
+ FILE *f = fopen(".", "r");
+ return f && fread(&c, 1, 1, f)]])],
+ [ac_cv_fread_reads_directories=no],
+ [ac_cv_fread_reads_directories=yes])
+])
+if test $ac_cv_fread_reads_directories = yes; then
+ FREAD_READS_DIRECTORIES=UnfortunatelyYes
+else
+ FREAD_READS_DIRECTORIES=
+fi
+AC_SUBST(FREAD_READS_DIRECTORIES)
+#
# Define SNPRINTF_RETURNS_BOGUS if your are on a system which snprintf()
# or vsnprintf() return -1 instead of number of characters which would
# have been written to the final string if enough space had been available.
--
