rules: allow arbitrary log destination

Add option BUILD_LOG_DIR to menuconfig to change log destination.

The mix-up of *DIR* and *FOLDER* is confusing however.

Signed-off-by: Paul Spooren <mail@aparcar.org>

config/Config-devel.in

@@ -105,6 +105,13 @@ menuconfig DEVEL
 		help
 		  If enabled, log files will be written to the ./log directory.
 
+	config BUILD_LOG_DIR
+		string "Log folder" if DEVEL
+		default ""
+		help
+		  Store build logs in this directory.
+		  If not set, uses './logs'
+
 	config SRC_TREE_OVERRIDE
 		bool "Enable package source tree override" if DEVEL
 		help

rules.mk

@@ -159,7 +159,7 @@ TARGET_ROOTFS_DIR?=$(if $(call qstrip,$(CONFIG_TARGET_ROOTFS_DIR)),$(call qstrip
 TARGET_DIR:=$(TARGET_ROOTFS_DIR)/root-$(BOARD)
 STAGING_DIR_ROOT:=$(STAGING_DIR)/root-$(BOARD)
 STAGING_DIR_IMAGE:=$(STAGING_DIR)/image
-BUILD_LOG_DIR:=$(TOPDIR)/logs
+BUILD_LOG_DIR:=$(if $(call qstrip,$(CONFIG_BUILD_LOG_DIR)),$(call qstrip,$(CONFIG_BUILD_LOG_DIR)),$(TOPDIR)/logs)
 PKG_INFO_DIR := $(STAGING_DIR)/pkginfo
 
 BUILD_DIR_HOST:=$(if $(IS_PACKAGE_BUILD),$(BUILD_DIR_BASE)/hostpkg,$(BUILD_DIR_BASE)/host)