west: Implement CMake helpers in scripts/west_commands
Move the existing CMake and build functionality from the west repository
to zephyr. The rationale behind this move is that it's very tightly
coupled with the Zephyr build system and is only used by the extension
commands implemented in the zephyr tree.
If additional extension commands in third-party repos want to use the
functionality they can add $ZEPHYR_BASE/scripts/west_commands to the
Python system path.
The implmentations in the west repo will be deprecated.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
diff --git a/scripts/west_commands/build_helpers.py b/scripts/west_commands/build_helpers.py
new file mode 100644
index 0000000..63cdebc
--- /dev/null
+++ b/scripts/west_commands/build_helpers.py
@@ -0,0 +1,65 @@
+# Copyright 2018 (c) Foundries.io.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+'''Common definitions for building Zephyr applications.
+
+This provides some default settings and convenience wrappers for
+building Zephyr applications needed by multiple commands.
+
+See build.py for the build command itself.
+'''
+
+import cmake
+import os
+from west import log
+
+DEFAULT_BUILD_DIR = 'build'
+'''Name of the default Zephyr build directory.'''
+
+DEFAULT_CMAKE_GENERATOR = 'Ninja'
+'''Name of the default CMake generator.'''
+
+BUILD_DIR_DESCRIPTION = '''\
+Explicitly sets the build directory. If not given and the current
+directory is a Zephyr build directory, it will be used; otherwise,
+"{}" is assumed.'''.format(DEFAULT_BUILD_DIR)
+
+
+def find_build_dir(dir):
+ '''Heuristic for finding a build directory.
+
+ If the given argument is truthy, it is returned. Otherwise, if
+ the current working directory is a build directory, it is
+ returned. Otherwise, DEFAULT_BUILD_DIR is returned.'''
+ if dir:
+ build_dir = dir
+ else:
+ cwd = os.getcwd()
+ if is_zephyr_build(cwd):
+ build_dir = cwd
+ else:
+ build_dir = DEFAULT_BUILD_DIR
+ return os.path.abspath(build_dir)
+
+
+def is_zephyr_build(path):
+ '''Return true if and only if `path` appears to be a valid Zephyr
+ build directory.
+
+ "Valid" means the given path is a directory which contains a CMake
+ cache with a 'ZEPHYR_TOOLCHAIN_VARIANT' key.
+ '''
+ try:
+ cache = cmake.CMakeCache.from_build_dir(path)
+ except FileNotFoundError:
+ cache = {}
+
+ if 'ZEPHYR_TOOLCHAIN_VARIANT' in cache:
+ log.dbg('{} is a zephyr build directory'.format(path),
+ level=log.VERBOSE_EXTREME)
+ return True
+ else:
+ log.dbg('{} is NOT a valid zephyr build directory'.format(path),
+ level=log.VERBOSE_EXTREME)
+ return False
