tools/cpp/lib_cc_configure.bzl - bazel - Git at Google

 # pylint: disable=g-bad-file-header
 # Copyright 2016 The Bazel Authors. All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
 #    http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
 """Base library for configuring the C++ toolchain."""


 def escape_string(arg):
   """Escape percent sign (%) in the string so it can appear in the Crosstool."""
   if arg != None:
     return str(arg).replace("%", "%%")
   else:
     return None

 def split_escaped(string, delimiter):
   """Split string on the delimiter unless %-escaped.

   Examples:
     Basic usage:
       split_escaped("a:b:c", ":") -> [ "a", "b", "c" ]

     Delimeter that is not supposed to be splitten on has to be %-escaped:
       split_escaped("a%:b", ":") -> [ "a:b" ]

     Literal % can be represented by escaping it as %%:
       split_escaped("a%%b", ":") -> [ "a%b" ]

     Consecutive delimiters produce empty strings:
       split_escaped("a::b", ":") -> [ "a", "", "", "b" ]

   Args:
     string: a string to be splitted
     delimiter: non-empty string not containing %-sign to be used as a delimiter

   Returns:
     a list of substrings
   """
   if delimiter == "": fail("Delimiter cannot be empty")
   if delimiter.find("%") != -1: fail("Delimiter cannot contain %-sign")

   i = 0
   result = []
   accumulator = []
   length = len(string)
   delimiter_length = len(delimiter)
    # Iterate over the length of string since Skylark doesn't have while loops
   for _ in range(length):
       if i >= length:
           break
       if i + 2 <= length and string[i : i + 2] == "%%":
           accumulator.append("%")
           i += 2
       elif (i + 1 + delimiter_length <= length and
               string[i : i + 1 + delimiter_length] == "%" + delimiter):
           accumulator.append(delimiter)
           i += 1 + delimiter_length
       elif i + delimiter_length <= length and string[i : i + delimiter_length] == delimiter:
           result.append(''.join(accumulator))
           accumulator = []
           i += delimiter_length
       else:
           accumulator.append(string[i])
           i += 1

   # Append the last group still in accumulator
   result.append(''.join(accumulator))
   return result


 def auto_configure_fail(msg):
   """Output failure message when auto configuration fails."""
   red = "\033[0;31m"
   no_color = "\033[0m"
   fail("\n%sAuto-Configuration Error:%s %s\n" % (red, no_color, msg))


 def auto_configure_warning(msg):
   """Output warning message during auto configuration."""
   yellow = "\033[1;33m"
   no_color = "\033[0m"
   print("\n%sAuto-Configuration Warning:%s %s\n" % (yellow, no_color, msg))


 def get_env_var(repository_ctx, name, default = None, enable_warning = True):
   """Find an environment variable in system path. Doesn't %-escape the value!"""
   if name in repository_ctx.os.environ:
     return repository_ctx.os.environ[name]
   if default != None:
     if enable_warning:
       auto_configure_warning("'%s' environment variable is not set, using '%s' as default" % (name, default))
     return default
   auto_configure_fail("'%s' environment variable is not set" % name)


 def which(repository_ctx, cmd, default = None):
   """A wrapper around repository_ctx.which() to provide a fallback value. Doesn't %-escape the value!"""
   result = repository_ctx.which(cmd)
   return default if result == None else str(result)


 def which_cmd(repository_ctx, cmd, default = None):
   """Find cmd in PATH using repository_ctx.which() and fail if cannot find it. Doesn't %-escape the cmd!"""
   result = repository_ctx.which(cmd)
   if result != None:
     return str(result)
   path = get_env_var(repository_ctx, "PATH")
   if default != None:
     auto_configure_warning("Cannot find %s in PATH, using '%s' as default.\nPATH=%s" % (cmd, default, path))
     return default
   auto_configure_fail("Cannot find %s in PATH, please make sure %s is installed and add its directory in PATH.\nPATH=%s" % (cmd, cmd, path))
   return str(result)


 def execute(repository_ctx, command, environment = None,
             expect_failure = False):
   """Execute a command, return stdout if succeed and throw an error if it fails. Doesn't %-escape the result!"""
   if environment:
     result = repository_ctx.execute(command, environment = environment)
   else:
     result = repository_ctx.execute(command)
   if expect_failure != (result.return_code != 0):
     if expect_failure:
       auto_configure_fail(
           "expected failure, command %s, stderr: (%s)" % (
               command, result.stderr))
     else:
       auto_configure_fail(
           "non-zero exit code: %d, command %s, stderr: (%s)" % (
               result.return_code, command, result.stderr))
   stripped_stdout = result.stdout.strip()
   if not stripped_stdout:
     auto_configure_fail(
         "empty output from command %s, stderr: (%s)" % (command, result.stderr))
   return stripped_stdout


 def get_cpu_value(repository_ctx):
   """Compute the cpu_value based on the OS name. Doesn't %-escape the result!"""
   os_name = repository_ctx.os.name.lower()
   if os_name.startswith("mac os"):
     return "darwin"
   if os_name.find("freebsd") != -1:
     return "freebsd"
   if os_name.find("windows") != -1:
     return "x64_windows"
   # Use uname to figure out whether we are on x86_32 or x86_64
   result = repository_ctx.execute(["uname", "-m"])
   if result.stdout.strip() in ["power", "ppc64le", "ppc", "ppc64"]:
     return "ppc"
   if result.stdout.strip() in ["arm", "armv7l", "aarch64"]:
     return "arm"
   return "k8" if result.stdout.strip() in ["amd64", "x86_64", "x64"] else "piii"


 def tpl(repository_ctx, template, substitutions={}, out=None):
   if not out:
     out = template
   repository_ctx.template(
       out,
       Label("@bazel_tools//tools/cpp:%s.tpl" % template),
       substitutions)


 def is_cc_configure_debug(repository_ctx):
   """Returns True if CC_CONFIGURE_DEBUG is set to 1."""
   env = repository_ctx.os.environ
   return "CC_CONFIGURE_DEBUG" in env and env["CC_CONFIGURE_DEBUG"] == "1"
	# pylint: disable=g-bad-file-header
	# Copyright 2016 The Bazel Authors. All rights reserved.
	#
	# Licensed under the Apache License, Version 2.0 (the "License");
	# you may not use this file except in compliance with the License.
	# You may obtain a copy of the License at
	#
	# http://www.apache.org/licenses/LICENSE-2.0
	#
	# Unless required by applicable law or agreed to in writing, software
	# distributed under the License is distributed on an "AS IS" BASIS,
	# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	# See the License for the specific language governing permissions and
	# limitations under the License.
	"""Base library for configuring the C++ toolchain."""


	def escape_string(arg):
	"""Escape percent sign (%) in the string so it can appear in the Crosstool."""
	if arg != None:
	return str(arg).replace("%", "%%")
	else:
	return None

	def split_escaped(string, delimiter):
	"""Split string on the delimiter unless %-escaped.

	Examples:
	Basic usage:
	split_escaped("a:b:c", ":") -> [ "a", "b", "c" ]

	Delimeter that is not supposed to be splitten on has to be %-escaped:
	split_escaped("a%:b", ":") -> [ "a:b" ]

	Literal % can be represented by escaping it as %%:
	split_escaped("a%%b", ":") -> [ "a%b" ]

	Consecutive delimiters produce empty strings:
	split_escaped("a::b", ":") -> [ "a", "", "", "b" ]

	Args:
	string: a string to be splitted
	delimiter: non-empty string not containing %-sign to be used as a delimiter

	Returns:
	a list of substrings
	"""
	if delimiter == "": fail("Delimiter cannot be empty")
	if delimiter.find("%") != -1: fail("Delimiter cannot contain %-sign")

	i = 0
	result = []
	accumulator = []
	length = len(string)
	delimiter_length = len(delimiter)
	# Iterate over the length of string since Skylark doesn't have while loops
	for _ in range(length):
	if i >= length:
	break
	if i + 2 <= length and string[i : i + 2] == "%%":
	accumulator.append("%")
	i += 2
	elif (i + 1 + delimiter_length <= length and
	string[i : i + 1 + delimiter_length] == "%" + delimiter):
	accumulator.append(delimiter)
	i += 1 + delimiter_length
	elif i + delimiter_length <= length and string[i : i + delimiter_length] == delimiter:
	result.append(''.join(accumulator))
	accumulator = []
	i += delimiter_length
	else:
	accumulator.append(string[i])
	i += 1

	# Append the last group still in accumulator
	result.append(''.join(accumulator))
	return result


	def auto_configure_fail(msg):
	"""Output failure message when auto configuration fails."""
	red = "\033[0;31m"
	no_color = "\033[0m"
	fail("\n%sAuto-Configuration Error:%s %s\n" % (red, no_color, msg))


	def auto_configure_warning(msg):
	"""Output warning message during auto configuration."""
	yellow = "\033[1;33m"
	no_color = "\033[0m"
	print("\n%sAuto-Configuration Warning:%s %s\n" % (yellow, no_color, msg))


	def get_env_var(repository_ctx, name, default = None, enable_warning = True):
	"""Find an environment variable in system path. Doesn't %-escape the value!"""
	if name in repository_ctx.os.environ:
	return repository_ctx.os.environ[name]
	if default != None:
	if enable_warning:
	auto_configure_warning("'%s' environment variable is not set, using '%s' as default" % (name, default))
	return default
	auto_configure_fail("'%s' environment variable is not set" % name)


	def which(repository_ctx, cmd, default = None):
	"""A wrapper around repository_ctx.which() to provide a fallback value. Doesn't %-escape the value!"""
	result = repository_ctx.which(cmd)
	return default if result == None else str(result)


	def which_cmd(repository_ctx, cmd, default = None):
	"""Find cmd in PATH using repository_ctx.which() and fail if cannot find it. Doesn't %-escape the cmd!"""
	result = repository_ctx.which(cmd)
	if result != None:
	return str(result)
	path = get_env_var(repository_ctx, "PATH")
	if default != None:
	auto_configure_warning("Cannot find %s in PATH, using '%s' as default.\nPATH=%s" % (cmd, default, path))
	return default
	auto_configure_fail("Cannot find %s in PATH, please make sure %s is installed and add its directory in PATH.\nPATH=%s" % (cmd, cmd, path))
	return str(result)


	def execute(repository_ctx, command, environment = None,
	expect_failure = False):
	"""Execute a command, return stdout if succeed and throw an error if it fails. Doesn't %-escape the result!"""
	if environment:
	result = repository_ctx.execute(command, environment = environment)
	else:
	result = repository_ctx.execute(command)
	if expect_failure != (result.return_code != 0):
	if expect_failure:
	auto_configure_fail(
	"expected failure, command %s, stderr: (%s)" % (
	command, result.stderr))
	else:
	auto_configure_fail(
	"non-zero exit code: %d, command %s, stderr: (%s)" % (
	result.return_code, command, result.stderr))
	stripped_stdout = result.stdout.strip()
	if not stripped_stdout:
	auto_configure_fail(
	"empty output from command %s, stderr: (%s)" % (command, result.stderr))
	return stripped_stdout


	def get_cpu_value(repository_ctx):
	"""Compute the cpu_value based on the OS name. Doesn't %-escape the result!"""
	os_name = repository_ctx.os.name.lower()
	if os_name.startswith("mac os"):
	return "darwin"
	if os_name.find("freebsd") != -1:
	return "freebsd"
	if os_name.find("windows") != -1:
	return "x64_windows"
	# Use uname to figure out whether we are on x86_32 or x86_64
	result = repository_ctx.execute(["uname", "-m"])
	if result.stdout.strip() in ["power", "ppc64le", "ppc", "ppc64"]:
	return "ppc"
	if result.stdout.strip() in ["arm", "armv7l", "aarch64"]:
	return "arm"
	return "k8" if result.stdout.strip() in ["amd64", "x86_64", "x64"] else "piii"


	def tpl(repository_ctx, template, substitutions={}, out=None):
	if not out:
	out = template
	repository_ctx.template(
	out,
	Label("@bazel_tools//tools/cpp:%s.tpl" % template),
	substitutions)


	def is_cc_configure_debug(repository_ctx):
	"""Returns True if CC_CONFIGURE_DEBUG is set to 1."""
	env = repository_ctx.os.environ
	return "CC_CONFIGURE_DEBUG" in env and env["CC_CONFIGURE_DEBUG"] == "1"