Add support for local packages through 'file://' pseudo-protocol

This can be used this way :

<pkg>_VERSION = 42
<pkg>_SITE = file:///some/local/directory
<pkg>_SOURCE = mypkg-$(<pkg>_VERSION).tar.bz2

Can be useful to integrate a home-made project or for testing purposes.
The default command to retrieve files is 'cp' but 'rsync' could also be used.
Through sshfs, it should also be possible to get non-public remote files on a
ssh server.

[ Thomas Petazzoni: use $(PKG)_SITE and $(PKG)_SOURCE variables
  instead of $(1) and $(2) ]
[ Peter: don't append $(QUIET), cp doesn't handle -q]
Signed-off-by: David Wagner <david.wagner@free-electrons.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

Config.in

@@ -32,6 +32,10 @@ config BR2_GIT
 	string "Git command"
 	default "git"
 
+config BR2_LOCALFILES
+	string "Local files retrieval command"
+	default "cp"
+
 config BR2_ZCAT
 	string "zcat command"
 	default "gzip -d -c"

package/Makefile.package.in

@@ -92,6 +92,7 @@ WGET:=$(call qstrip,$(BR2_WGET)) $(QUIET)
 SVN:=$(call qstrip,$(BR2_SVN)) $(QUIET)
 BZR:=$(call qstrip,$(BR2_BZR)) $(QUIET)
 GIT:=$(call qstrip,$(BR2_GIT)) $(QUIET)
+LOCALFILES:=$(call qstrip,$(BR2_LOCALFILES))
 
 # Default spider mode is 'DOWNLOAD'. Other possible values are 'SOURCE_CHECK'
 # used by the _source-check target and 'SHOW_EXTERNAL_DEPS', used by the
@@ -104,18 +105,18 @@ DL_DIR:=$(TOPDIR)/dl
 endif
 
 ################################################################################
-# The DOWNLOAD_{GIT,SVN,BZR} helpers are in charge of getting a
+# The DOWNLOAD_{GIT,SVN,BZR,LOCALFILES} helpers are in charge of getting a
 # working copy of the source repository for their corresponding SCM,
 # checking out the requested version / commit / tag, and create an
 # archive out of it. DOWNLOAD_WGET is the normal wget-based download
 # mechanism.
 #
-# The SOURCE_CHECK_{GIT,SVN,BZR,WGET} helpers are in charge of simply
+# The SOURCE_CHECK_{GIT,SVN,BZR,WGET,LOCALFILES} helpers are in charge of simply
 # checking that the source is available for download. This can be used
 # to make sure one will be able to get all the sources needed for
 # one's build configuration.
 #
-# The SHOW_EXTERNAL_DEPS_{GIT,SVN,BZR,WGET} helpers simply output to
+# The SHOW_EXTERNAL_DEPS_{GIT,SVN,BZR,WGET,LOCALFILES} helpers simply output to
 # the console the names of the files that will be downloaded, or path
 # and revision of the source repositories, producing a list of all the
 # "external dependencies" of a given build configuration.
@@ -189,6 +190,19 @@ define SHOW_EXTERNAL_DEPS_WGET
   echo $(2)
 endef
 
+define DOWNLOAD_LOCALFILES
+	test -e $(DL_DIR)/$($(PKG)_SOURCE) || \
+		$(LOCALFILES) $(call qstrip,$(subst file://,,$($(PKG)_SITE)))/$($(PKG)_SOURCE) $(DL_DIR)
+endef
+
+define SOURCE_CHECK_LOCALFILES
+  test -e $(call qstrip,$(subst file://,,$($(PKG)_SITE)))/$($(PKG)_SOURCE)
+endef
+
+define SHOW_EXTERNAL_DEPS_LOCALFILES
+  echo $($(PKG)_SITE)/$($(PKG)_SOURCE)
+endef
+
 ################################################################################
 # DOWNLOAD -- Download helper. Will try to download source from:
 # 1) BR2_PRIMARY_SITE if enabled
@@ -211,6 +225,7 @@ define DOWNLOAD
 			git) $($(DL_MODE)_GIT) && exit ;; \
 			svn) $($(DL_MODE)_SVN) && exit ;; \
 			bzr) $($(DL_MODE)_BZR) && exit ;; \
+			file) $($(DL_MODE)_LOCALFILES) && exit ;; \
 			*) $(call $(DL_MODE)_WGET,$(1),$(2)) && exit ;; \
 		esac ; \
 	fi ; \