Allow for disabling contrib downloads

This adds the support for the DISABLE_CONTRIB_DOWNLOADS environment
variable. It if it set to TRUE, the contrib system will not download
tarballs from the internet.

It can be set from the bootstrap script with the --disable-downloads
option.

This is useful for distro packaging because distribution developpers
have to make sure they have full control of what is included in the
package. In Debian, some tarballs are included such as pjsip but the
rest should not be downloaded. A small mistake such as a missging build
dependency could cause a tarball download. This new options will help
pervent such issues.

Tuleap: #847
Change-Id: I5f579774c53def751111f9366750670fcd75d893

contrib/bootstrap

@@ -21,11 +21,12 @@
 usage()
 {
 	echo "Usage: $0 [--build=BUILD] [--host=HOST] [--prefix=PREFIX]"
-	echo "  --build=BUILD    configure for building on BUILD"
-	echo "  --host=HOST      cross-compile to build to run on HOST"
-	echo "  --prefix=PREFIX  install files in PREFIX"
-	echo "  --disable-FOO    configure to not build package FOO"
-	echo "  --enable-FOO     configure to build package FOO"
+	echo "  --build=BUILD       configure for building on BUILD"
+	echo "  --host=HOST         cross-compile to build to run on HOST"
+	echo "  --prefix=PREFIX     install files in PREFIX"
+	echo "  --disable-downloads don't download packages from the internet"
+	echo "  --disable-FOO       configure to not build package FOO"
+	echo "  --enable-FOO        configure to build package FOO"
 }
 
 BUILD=
@@ -50,6 +51,9 @@ do
 			usage
 			exit 0
 			;;
+		--disable-downloads)
+			DISABLE_CONTRIB_DOWNLOADS="TRUE"
+			;;
 		--host=*)
 			HOST="${1#--host=}"
 			;;
@@ -108,6 +112,7 @@ HOST := $HOST
 CROSS_COMPILE ?= $HOST-
 PKGS_DISABLE := $PKGS_DISABLE
 PKGS_ENABLE := $PKGS_ENABLE
+DISABLE_CONTRIB_DOWNLOADS := $DISABLE_CONTRIB_DOWNLOADS
 EOF
 
 add_make()

contrib/src/main.mak

@@ -232,7 +232,9 @@ endif
 endif
 SVN ?= $(error subversion client (svn) not found!)
 
-ifeq ($(shell curl --version >/dev/null 2>&1 || echo FAIL),)
+ifeq ($(DISABLE_CONTRIB_DOWNLOADS),TRUE)
+download = $(error Trying to download $(1) but DISABLE_CONTRIB_DOWNLOADS is TRUE, aborting.)
+else ifeq ($(shell curl --version >/dev/null 2>&1 || echo FAIL),)
 download = curl -f -L --retry-delay 10 --retry 2 -- "$(1)" > "$@"
 else ifeq ($(shell wget --version >/dev/null 2>&1 || echo FAIL),)
 download = rm -f $@.tmp && \
@@ -316,6 +318,9 @@ HOSTVARS := $(HOSTTOOLS) \
 	CXXFLAGS="$(CXXFLAGS) $(PIC)" \
 	LDFLAGS="$(LDFLAGS)"
 
+ifeq ($(DISABLE_CONTRIB_DOWNLOADS),TRUE)
+download_git = $(error Trying to clone $(1) but DISABLE_CONTRIB_DOWNLOADS is TRUE, aborting.)
+else
 download_git = \
 	rm -Rf $(@:.tar.xz=) && \
 	$(GIT) clone $(2:%=--branch %) $(1) $(@:.tar.xz=) && \
@@ -324,6 +329,8 @@ download_git = \
 	(cd $(dir $@) && \
 	tar cvJ $(notdir $(@:.tar.xz=))) > $@ && \
 	rm -Rf $(@:.tar.xz=)
+endif
+
 checksum = \
 	$(foreach f,$(filter $(TARBALLS)/%,$^), \
 		grep -- " $(f:$(TARBALLS)/%=%)$$" \