ccache: provide capability to do initial ccache setup

For example, if your project is known to require more space than the
default max cache size, then you might want to increase the cache size
to a suitable amount using the -M (--max-size) option.

The string you specify here is passed verbatim to ccache.  Refer to
ccache documentation for more details.

These initial settings are applied after ccache has been compiled.

Signed-off-by: Danomi Manchego <danomimanchego123@gmail.com>
Reviewed-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Tested-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

Config.in

@@ -266,7 +266,7 @@ config BR2_CCACHE
 	help
 	  This option will enable the use of ccache, a compiler
 	  cache. It will cache the result of previous builds to speed
-	  up future builds. The cache is stored in
+	  up future builds. By default, the cache is stored in
 	  $HOME/.buildroot-ccache.
 
 	  Note that Buildroot does not try to invalidate the cache
@@ -276,13 +276,30 @@ config BR2_CCACHE
 	  ccache cache by removing the $HOME/.buildroot-ccache
 	  directory.
 
+if BR2_CCACHE
+
 config BR2_CCACHE_DIR
 	string "Compiler cache location"
-	depends on BR2_CCACHE
 	default "$(HOME)/.buildroot-ccache"
 	help
 	  Where ccache should store cached files.
 
+config BR2_CCACHE_INITIAL_SETUP
+	string "Compiler cache initial setup"
+	help
+	  Initial ccache settings to apply, such as --max-files or --max-size.
+
+	  For example, if your project is known to require more space than the
+	  default max cache size, then you might want to increase the cache size
+	  to a suitable amount using the -M (--max-size) option.
+
+	  The string you specify here is passed verbatim to ccache.  Refer to
+	  ccache documentation for more details.
+
+	  These initial settings are applied after ccache has been compiled.
+
+endif
+
 config BR2_DEPRECATED
 	bool "Show packages that are deprecated or obsolete"
 	help

package/ccache/ccache.mk

@@ -38,15 +38,25 @@ define HOST_CCACHE_PATCH_CONFIGURATION
 	sed -i 's,"%s/.ccache","$(BR_CACHE_DIR)",' $(@D)/ccache.c
 endef
 
-HOST_CCACHE_POST_CONFIGURE_HOOKS += \
-	HOST_CCACHE_PATCH_CONFIGURATION
+HOST_CCACHE_POST_CONFIGURE_HOOKS += HOST_CCACHE_PATCH_CONFIGURATION
 
 define HOST_CCACHE_MAKE_CACHE_DIR
 	mkdir -p $(BR_CACHE_DIR)
 endef
 
-HOST_CCACHE_POST_INSTALL_HOOKS += \
-	HOST_CCACHE_MAKE_CACHE_DIR
+HOST_CCACHE_POST_INSTALL_HOOKS += HOST_CCACHE_MAKE_CACHE_DIR
+
+# Provide capability to do initial ccache setup (e.g. increase default size)
+BR_CCACHE_INITIAL_SETUP = $(call qstrip,$(BR2_CCACHE_INITIAL_SETUP))
+ifneq ($(BR_CCACHE_INITIAL_SETUP),)
+define HOST_CCACHE_DO_INITIAL_SETUP
+	@$(call MESSAGE,"Applying initial settings")
+	$(CCACHE) $(BR_CCACHE_INITIAL_SETUP)
+	$(CCACHE) -s
+endef
+
+HOST_CCACHE_POST_INSTALL_HOOKS += HOST_CCACHE_DO_INITIAL_SETUP
+endif
 
 $(eval $(host-autotools-package))