From 15579e94d3d969507f76a6f570e2066d5787c8a4 Mon Sep 17 00:00:00 2001
From: Jan Lindemann <jan@janware.com>
Date: Mon, 24 Jun 2019 12:44:14 +0000
Subject: [PATCH] projects.mk + defs.mk: Make some variables more universally
 usable

- Remove temporary variable PRJS_DIR
- Add defaults for BUILD_LIBS_PREFIX and BUILD_TOOLS_PREFIX
- Move definitions of varables needed early on from defs.mk
  into projects.mk, such as PYTHON and PYTHON_VERSION

Signed-off-by: Jan Lindemann <jan@janware.com>
---
 make/defs.mk     | 17 +++++++++++++----
 make/projects.mk | 26 +++++++++++++++++++-------
 2 files changed, 32 insertions(+), 11 deletions(-)

diff --git a/make/defs.mk b/make/defs.mk
index f655cc20..176df691 100644
--- a/make/defs.mk
+++ b/make/defs.mk
@@ -11,6 +11,8 @@ empty                       :=
 space                       := $(empty) $(empty)
 comma                       := ,
 
+# ----- executables
+
 include $(MODDIR)/make/projects.mk
 
 ifeq ($(MAKE_BENCHMARK),true)
@@ -19,10 +21,6 @@ else
   export SHELL              := /bin/bash
 endif
 
-# ----- executables
-ifndef WHICH
-  WHICH                     := $(firstword $(wildcard /usr/bin/which) $(shell which which))
-endif
 ifndef GREP
   GREP                      := $(shell $(WHICH) grep)
 endif
@@ -157,6 +155,17 @@ else ifneq ($(wildcard $(TOPDIR)/CVS),)
   VCS                       ?= cvs
 endif
 
+ifndef BUILD_TOOLS_PREFIX
+  ifdef BUILD_LIBS_PREFIX
+    BUILD_TOOLS_PREFIX       = $(BUILD_LIBS_PREFIX)
+  endif
+endif
+ifdef BUILD_LIBS_PREFIX
+  ifndef BUILD_TOOLS_PREFIX
+    BUILD_LIBS_PREFIX        = $(BUILD_TOOLS_PREFIX)
+  endif
+endif
+
 # ----- user and organization
 
 ifndef BUILD_USER
diff --git a/make/projects.mk b/make/projects.mk
index 2731040c..e6668e03 100644
--- a/make/projects.mk
+++ b/make/projects.mk
@@ -13,17 +13,29 @@ ifndef DEVELOPMENT
 endif
 
 # -- Conclude the build system's location:
-PROJECTS_DIR                ?= $(TOPDIR)/..
-ifeq ($(DEVELOPMENT),true)
-  PRJS_DIR                  ?= $(PROJECTS_DIR)
-else
-  PRJS_DIR                  ?= /opt
+ifeq ($(PROJECTS_DIR),)
+  ifeq ($(DEVELOPMENT),true)
+    PROJECTS_DIR            ?= $(TOPDIR)/..
+  else
+    PROJECTS_DIR            ?= /opt
+  endif
 endif
 
 # -- Query the build system about other projects:
-PYTHON                      ?= /usr/bin/python3
+
+ifndef WHICH
+  WHICH                     := $(firstword $(wildcard /usr/bin/which) $(shell which which))
+endif
+
+ifeq ($(PYTHON),)
+  PYTHON_VERSION            := 3
+  PYTHON                    := $(shell $(WHICH) python$(PYTHON_VERSION))
+else
+  PYTHON_VERSION            := $(word 2,$(subst ., ,$(shell $(PYTHON) --version)))
+endif
+
 ifneq ($(TOPDIR),)
-  proj_query_cmd             = $(PYTHON) $(MOD_SCRIPT_DIR)/projects.py -p $(PRJS_DIR) -t $(TOPDIR) $(PROJECTS_PY_EXTRA_ARGS)
+  proj_query_cmd             = $(PYTHON) $(MOD_SCRIPT_DIR)/projects.py -p $(PROJECTS_DIR) -t $(TOPDIR) $(PROJECTS_PY_EXTRA_ARGS)
   proj_query                 = $(shell $(proj_query_cmd) $(1))
   proj_dir                   = $(call proj_query,proj-dir $(1))
   htdocs_dir                 = $(call proj_query,htdocs-dir $(1))