kumquat-buildroot/package/pkg-download.mk
Yann E. MORIN 632e164a19 core: ensure we use the realpath(3) of DL_DIR
When $(TOPDIR)/dl is a symlink, checking out git submodules can fail,
as reported by Michael in #11086.

To reproduce a similarly-related mis-behaviour:

    $ mkdir -p foo/bar foo/buz
    $ cd foo/bar
    $ ln -s ../buz meh
    $ cd meh
    $ cd ../../foo

The last command should not succeed, because, relative to meh, there is
no ../../foo directory; we would expect it to be ../../../foo, instead.
But since meh is a symlink to a directory, then a relative path from that
symlink is interpreted as relative to the derefrenced directory, i.e.
from buz in this case.

But where this gets even weirder, is that, if the last command is
replaced by:

    $ cd ../../../foo

then it still works, too.

And that is the root of Michael's issue: the dl directory in Buildroot's
TOPDIR is a symlink to a similarly-named directory one directory higher,
which then confuses relative paths, which gets especially and noticeably
bad for git submodules.

Avoid this strangeness, and just use so-called "physical" path, i.e. a
path where all symlinks to directories have been dereferenced.

Fixes: #11086

Reported-by: Michael Nosthoff <posted@heine.so>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Michael Nosthoff <posted@heine.so>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
2018-11-18 19:35:50 +01:00

110 lines
3.8 KiB
Makefile

################################################################################
#
# This file contains the download helpers for the various package
# infrastructures. It is used to handle downloads from HTTP servers,
# FTP servers, Git repositories, Subversion repositories, Mercurial
# repositories, Bazaar repositories, and SCP servers.
#
################################################################################
# Download method commands
export WGET := $(call qstrip,$(BR2_WGET))
export SVN := $(call qstrip,$(BR2_SVN))
export CVS := $(call qstrip,$(BR2_CVS))
export BZR := $(call qstrip,$(BR2_BZR))
export GIT := $(call qstrip,$(BR2_GIT))
export HG := $(call qstrip,$(BR2_HG))
export SCP := $(call qstrip,$(BR2_SCP))
SSH := $(call qstrip,$(BR2_SSH))
export LOCALFILES := $(call qstrip,$(BR2_LOCALFILES))
DL_WRAPPER = support/download/dl-wrapper
FLOCK = flock $($(PKG)_DL_DIR)/
# DL_DIR may have been set already from the environment
ifeq ($(origin DL_DIR),undefined)
DL_DIR ?= $(call qstrip,$(BR2_DL_DIR))
ifeq ($(DL_DIR),)
DL_DIR := $(TOPDIR)/dl
endif
else
# Restore the BR2_DL_DIR that was overridden by the .config file
BR2_DL_DIR = $(DL_DIR)
endif
# ensure it exists and a absolute path, derefrecing symlinks
DL_DIR := $(shell mkdir -p $(DL_DIR) && cd $(DL_DIR) >/dev/null && pwd -P)
#
# URI scheme helper functions
# Example URIs:
# * http://www.example.com/dir/file
# * scp://www.example.com:dir/file (with domainseparator :)
#
# geturischeme: http
geturischeme = $(firstword $(subst ://, ,$(call qstrip,$(1))))
# getschemeplusuri: git|parameter+http://example.com
getschemeplusuri = $(call geturischeme,$(1))$(if $(2),\|$(2))+$(1)
# stripurischeme: www.example.com/dir/file
stripurischeme = $(lastword $(subst ://, ,$(call qstrip,$(1))))
# domain: www.example.com
domain = $(firstword $(subst $(call domainseparator,$(2)), ,$(call stripurischeme,$(1))))
# notdomain: dir/file
notdomain = $(patsubst $(call domain,$(1),$(2))$(call domainseparator,$(2))%,%,$(call stripurischeme,$(1)))
#
# default domainseparator is /, specify alternative value as first argument
domainseparator = $(if $(1),$(1),/)
# github(user,package,version): returns site of GitHub repository
github = https://github.com/$(1)/$(2)/archive/$(3)
# Expressly do not check hashes for those files
# Exported variables default to immediately expanded in some versions of
# make, but we need it to be recursively-epxanded, so explicitly assign it.
export BR_NO_CHECK_HASH_FOR =
################################################################################
# DOWNLOAD -- Download helper. Will call DL_WRAPPER which will try to download
# source from:
# 1) BR2_PRIMARY_SITE if enabled
# 2) Download site, unless BR2_PRIMARY_SITE_ONLY is set
# 3) BR2_BACKUP_SITE if enabled, unless BR2_PRIMARY_SITE_ONLY is set
#
# Argument 1 is the source location
#
################################################################################
ifneq ($(call qstrip,$(BR2_PRIMARY_SITE)),)
DOWNLOAD_URIS += \
-u $(call getschemeplusuri,$(call qstrip,$(BR2_PRIMARY_SITE)/$($(PKG)_DL_SUBDIR)),urlencode) \
-u $(call getschemeplusuri,$(call qstrip,$(BR2_PRIMARY_SITE)),urlencode)
endif
ifeq ($(BR2_PRIMARY_SITE_ONLY),)
DOWNLOAD_URIS += \
-u $(patsubst %/,%,$(dir $(call qstrip,$(1))))
ifneq ($(call qstrip,$(BR2_BACKUP_SITE)),)
DOWNLOAD_URIS += \
-u $(call getschemeplusuri,$(call qstrip,$(BR2_BACKUP_SITE)/$($(PKG)_DL_SUBDIR)),urlencode) \
-u $(call getschemeplusuri,$(call qstrip,$(BR2_BACKUP_SITE)),urlencode)
endif
endif
define DOWNLOAD
$(Q)mkdir -p $($(PKG)_DL_DIR)
$(Q)$(EXTRA_ENV) $(FLOCK) $(DL_WRAPPER) \
-c '$($(PKG)_DL_VERSION)' \
-d '$($(PKG)_DL_DIR)' \
-D '$(DL_DIR)' \
-f '$(notdir $(1))' \
-H '$($(PKG)_HASH_FILE)' \
-n '$($(PKG)_BASENAME_RAW)' \
-N '$($(PKG)_RAWNAME)' \
-o '$($(PKG)_DL_DIR)/$(notdir $(1))' \
$(if $($(PKG)_GIT_SUBMODULES),-r) \
$(DOWNLOAD_URIS) \
$(QUIET) \
-- \
$($(PKG)_DL_OPTS)
endef