package/proftpd: add enable buffer size

Enable buffer size as a compile time option to change internal
buffer size.

Signed-off-by: Jared Bents <jared.bents@rockwellcollins.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

package/proftpd/Config.in

@@ -65,4 +65,17 @@ config BR2_PACKAGE_PROFTPD_MOD_QUOTATAB_SQL
 	  Compile mod_quotatab with mod_quotatab_sql table.
 
 endif
+
+config BR2_PACKAGE_PROFTPD_BUFFER_SIZE
+	int "buffer size in bytes (0 for default)"
+	default "0"
+	help
+	  By increasing the buffer size above the default of 1K,
+	  proftpd reads and writes data in larger chunks, and makes
+	  fewer expensive system calls. Use of this option to set buffer
+	  sizes of 8K or more has been reported to drastically increase
+	  transfer speeds (depending on network configurations).
+
+	  0 uses the default size of 1024.
+
 endif

package/proftpd/proftpd.mk

@@ -121,4 +121,8 @@ define PROFTPD_INSTALL_INIT_SYSTEMD
 		$(TARGET_DIR)/etc/systemd/system/multi-user.target.wants/proftpd.service
 endef
 
+ifneq ($(BR2_PACKAGE_PROFTPD_BUFFER_SIZE),0)
+PROFTPD_CONF_OPTS += --enable-buffer-size=$(BR2_PACKAGE_PROFTPD_BUFFER_SIZE)
+endif
+
 $(eval $(autotools-package))