[Buildroot] [PATCH 2/6] pkg-infra: move git download helper to a script

[Yann E. MORIN]

From: "Yann E. MORIN" <yann.morin.1998 at free.fr>

The git download helper is getting a bit more complex, and does not
raise an error when a PKG_VERSION is a sha1 that does not exist in
the repository. Instead, it generates an empty archive.

Fixing it in the Makefile proves to be challenging, to say the least.

Move it into a shell script in support/download/git, which will make
it much easier to read, maintain, fix an enhance in the future.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998 at free.fr>
Cc: Peter Korsgaard <jacmet at uclibc.org>
Cc: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
---
 package/pkg-download.mk | 16 +++-------------
 support/download/git    | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 39 insertions(+), 13 deletions(-)
 create mode 100755 support/download/git

diff --git a/package/pkg-download.mk b/package/pkg-download.mk
index c00689b..8e6f7a3 100644
--- a/package/pkg-download.mk
+++ b/package/pkg-download.mk
@@ -12,7 +12,7 @@ WGET := $(call qstrip,$(BR2_WGET)) $(QUIET)
 SVN := $(call qstrip,$(BR2_SVN))
 CVS := $(call qstrip,$(BR2_CVS))
 BZR := $(call qstrip,$(BR2_BZR))
-GIT := $(call qstrip,$(BR2_GIT))
+export GIT := $(call qstrip,$(BR2_GIT))
 HG := $(call qstrip,$(BR2_HG)) $(QUIET)
 SCP := $(call qstrip,$(BR2_SCP)) $(QUIET)
 SSH := $(call qstrip,$(BR2_SSH)) $(QUIET)
@@ -84,18 +84,8 @@ github = https://github.com/$(1)/$(2)/tarball/$(3)
 # problems
 define DOWNLOAD_GIT
 	test -e $(DL_DIR)/$($(PKG)_SOURCE) || \
-	(pushd $(DL_DIR) > /dev/null && \
-	 ((test "`git ls-remote $($(PKG)_SITE) $($(PKG)_DL_VERSION)`" && \
-	   echo "Doing shallow clone" && \
-	   $(GIT) clone --depth 1 -b $($(PKG)_DL_VERSION) --bare $($(PKG)_SITE) $($(PKG)_BASE_NAME)) || \
-	  (echo "Doing full clone" && \
-	   $(GIT) clone --bare $($(PKG)_SITE) $($(PKG)_BASE_NAME))) && \
-	pushd $($(PKG)_BASE_NAME) > /dev/null && \
-	$(GIT) archive --format=tar --prefix=$($(PKG)_BASE_NAME)/ $($(PKG)_DL_VERSION) | \
-		gzip -c > $(DL_DIR)/$($(PKG)_SOURCE) && \
-	popd > /dev/null && \
-	rm -rf $($(PKG)_DL_DIR) && \
-	popd > /dev/null)
+	$(EXTRA_ENV) support/download/git $($(PKG)_SITE) $($(PKG)_DL_VERSION) \
+					  $($(PKG)_BASE_NAME)/ $(DL_DIR)/$($(PKG)_SOURCE)
 endef
 
 # TODO: improve to check that the given PKG_DL_VERSION exists on the remote
diff --git a/support/download/git b/support/download/git
new file mode 100755
index 0000000..99ea1b2
--- /dev/null
+++ b/support/download/git
@@ -0,0 +1,36 @@
+#!/bin/sh
+set -e
+
+# Download helper for git
+# Call it with:
+#   $1: git repo
+#   $2: git cset
+#   $3: prefix/
+#   $4: output file
+# And this environment:
+#   GIT      :  the git command to call
+#   BUILD_DIR:  path to Buildroot's build dir
+
+repo="${1}"
+cset="${2}"
+prefix="${3}"
+output="${4}"
+
+pushd "${BUILD_DIR}" >/dev/null
+rm -rf .git-tmp-repo    # In case a previous attempt was interrupted
+
+if [ -n "$(${GIT} ls-remote "${repo}" "${cset}" 2>&1)" ]; then
+    printf "Doing shallow clone\n"
+    ${GIT} clone --depth 1 -b "${cset}" --bare "${repo}" .git-tmp-repo
+else
+    printf "Doing full clone\n"
+    ${GIT} clone --bare "${repo}" .git-tmp-repo
+fi
+
+pushd .git-tmp-repo >/dev/null
+${GIT} archive --prefix="${prefix}" --format=tar "${cset}"  \
+|gzip -c >"${output}"
+popd >/dev/null
+
+rm -rf .git-tmp-repo
+popd >/dev/null
-- 
1.8.1.2