Manual sync with develop (#95)

Brings all features from develop. Note that RELEASE.txt has not been
updated (will be done in a future PR).

1 files changed, 51 insertions, 0 deletions

diff --git a/configure.ac b/configure.ac
index ea3250e..9880223 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1211,6 +1211,7 @@ AC_CHECK_HEADERS([stddef.h setjmp.h features.h])
 AC_CHECK_HEADERS([dirent.h])
 AC_CHECK_HEADERS([stdint.h], [C9x=yes])
 AC_CHECK_HEADERS([stdbool.h])
+AC_CHECK_HEADERS([netdb.h netinet/in.h arpa/inet.h])
 
 ## Darwin
 AC_SUBST([H5_IS_DARWIN])
@@ -2379,6 +2380,56 @@ case "X-$OPTIMIZATION" in
 esac
 
 ## ----------------------------------------------------------------------
+## Check if file locking should be used
+##
+AC_MSG_CHECKING([enable file locking])
+AC_ARG_ENABLE([file-locking],
+              [AS_HELP_STRING([--enable-file-locking=(yes|no|best-effort)],
+                              [Sets the default for whether or not to use file
+                               locking when opening files. Can be overridden
+                               with the HDF5_USE_FILE_LOCKING environment variable
+                               and the H5Pset_file_locking() API call.
+                               best-effort attempts to use file locking but does
+                               not fail when file locks have been disabled on
+                               the file system (useful with Lustre).
+                               [default=best-effort]
+                               ])],
+              [DESIRED_FILE_LOCKING=$enableval])
+
+## Set defaults
+if test "X-$DESIRED_FILE_LOCKING" = X- ; then
+  DESIRED_FILE_LOCKING=best-effort
+fi
+
+## Allow this variable to be substituted in
+## other files (src/libhdf5.settings.in, etc.)
+AC_SUBST([DESIRED_FILE_LOCKING])
+AC_SUBST([USE_FILE_LOCKING])
+AC_SUBST([IGNORE_DISABLED_FILE_LOCKS])
+
+case "X-$DESIRED_FILE_LOCKING" in
+  X-best-effort)
+      AC_MSG_RESULT([best-effort])
+      AC_DEFINE([USE_FILE_LOCKING], [1],
+                [Define if the library will use file locking])
+      AC_DEFINE([IGNORE_DISABLED_FILE_LOCKS], [1],
+                [Define if the library will ignore file locks when disabled])
+    ;;
+  X-yes)
+      AC_MSG_RESULT([yes])
+      AC_DEFINE([USE_FILE_LOCKING], [1],
+                [Define if the library will use file locking])
+    ;;
+  X-no)
+      AC_MSG_RESULT([no])
+    ;;
+  *)
+      AC_MSG_ERROR([Unrecognized value: $USE_FILE_LOCKING])
+    ;;
+esac
+
+
+## ----------------------------------------------------------------------
 ## Enable/disable internal package-level debugging output
 ##
 AC_MSG_CHECKING([for internal debug output])