# -*- mode:python -*-

# Copyright (c) 2004-2005 The Regents of The University of Michigan
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met: redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer;
# redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution;
# neither the name of the copyright holders nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

###################################################
#
# SCons top-level build description (SConstruct) file.
#
# To build M5, you need a directory with three things:
# 1. A copy of this file (named SConstruct).
# 2. A link named 'm5' to the top of the M5 simulator source tree.
# 3. A link named 'ext' to the top of the M5 external source tree.
#
# Then type 'scons' to build the default configuration (see below), or
# 'scons <CONFIG>/<binary>' to build some other configuration (e.g.,
# 'ALPHA_FS/m5.opt' for the optimized full-system version).
#
###################################################

# Python library imports
import sys
import os

# The absolute path to the current directory (where this file lives).
ROOT = Dir('.').abspath

# Paths to the M5 and external source trees (local symlinks).
SRCDIR = os.path.join(ROOT, 'm5')
EXT_SRCDIR = os.path.join(ROOT, 'ext')

# Check for 'm5' and 'ext' links, die if they don't exist.
if not os.path.isdir(SRCDIR):
    print "Error: '%s' must be a link to the M5 source tree." % SRCDIR
    sys.exit(1)

if not os.path.isdir('ext'):
    print "Error: '%s' must be a link to the M5 external source tree." \
          % EXT_SRCDIR
    sys.exit(1)

# tell python where to find m5 python code
sys.path.append(os.path.join(SRCDIR, 'python'))


###################################################
#
# Define Configurations
#
# The build system infers the build options from the subdirectory name
# that the simulator is built under.  The subdirectory name must be of
# the form <CONFIG>[.<OPT>]*, where <CONFIG> is a base configuration
# (e.g., ALPHA_SE or ALPHA_FS) and OPT is an option (e.g., MYSQL).  The
# following code defines the standard configurations and options.
# Additional local configurations and options are read from the file
# 'local_configs' if it exists.
#
# Each base configuration or option is defined in two steps: a
# function that takes an SCons build environment and modifies it
# appropriately for that config or option, and an entry in the
# 'configs_map' or 'options_map' dictionary that maps the directory
# name string to the function.  (The directory names are all upper
# case, by convention.)
#
###################################################

# Base non-full-system Alpha ISA configuration.
def AlphaSyscallEmulConfig(env):
    env.Replace(TARGET_ISA = 'alpha')
    env.Append(CPPDEFINES = 'SS_COMPATIBLE_FP')

# Base full-system configuration.
def AlphaFullSysConfig(env):
    env.Replace(TARGET_ISA = 'alpha')
    env.Replace(FULL_SYSTEM = True)
    env.Append(CPPDEFINES = ['FULL_SYSTEM'])

# Base configurations map.
configs_map = {
    'ALPHA_SE' : AlphaSyscallEmulConfig,
    'ALPHA_FS' : AlphaFullSysConfig
    }

# Disable FastAlloc object allocation.
def NoFastAllocOpt(env):
    env.Append(CPPDEFINES = 'NO_FAST_ALLOC')

# Enable efence
def EfenceOpt(env):
    env.Append(LIBS=['efence'])

# Configuration options map.
options_map = {
    'NO_FAST_ALLOC' : NoFastAllocOpt,
    'EFENCE' : EfenceOpt
    }

# The 'local_configs' file can be used to define additional base
# configurations and/or options without changing this file.
if os.path.isfile('local_configs'):
    SConscript('local_configs', exports = ['configs_map', 'options_map'])

# This function parses a directory name of the form <CONFIG>[.<OPT>]*
# and sets up the build environment appropriately.  Returns True if
# successful, False if the base config or any of the options were not
# defined.
def set_dir_options(dir, env):
    parts = dir.split('.')
    config = parts[0]
    opts = parts[1:]
    try:
        configs_map[config](env)
        map(lambda opt: options_map[opt](env), opts)
        return True
    except KeyError, key:
        print "Config/option '%s' not found." % key
        return False

# Set the default configuration and binary.  The default target (if
# scons is invoked at the top level with no command-line targets) is
# 'ALPHA_SE/m5.debug'.  If scons is invoked in a subdirectory with no
# command-line targets, the configuration

###################################################
#
# Figure out which configurations to set up.
#
#
# It's prohibitive to do all the combinations of base configurations
# and options, so we have to infer which ones the user wants.
#
# 1. If there are command-line targets, the configuration(s) are inferred
#    from the directories of those targets.  If scons was invoked from a
#    subdirectory (using 'scons -u'), those targets have to be
#    interpreted relative to that subdirectory.
#
# 2. If there are no command-line targets, and scons was invoked from a
#    subdirectory (using 'scons -u'), the configuration is inferred from
#    the name of the subdirectory.
#
# 3. If there are no command-line targets and scons was invoked from
#    the root build directory, a default configuration is used.  The
#    built-in default is ALPHA_SE, but this can be overridden by setting the
#    M5_DEFAULT_CONFIG shell environment veriable.
#
# In cases 2 & 3, the specific file target defaults to 'm5.debug', but
# this can be overridden by setting the M5_DEFAULT_BINARY shell
# environment veriable.
#
###################################################

# Find default configuration & binary.
default_config = os.environ.get('M5_DEFAULT_CONFIG', 'ALPHA_SE')
default_binary = os.environ.get('M5_DEFAULT_BINARY', 'm5.debug')

# Ask SCons which directory it was invoked from.  If you invoke SCons
# from a subdirectory you must use the '-u' flag.
launch_dir = GetLaunchDir()

# Build a list 'my_targets' of all the targets relative to ROOT.
if launch_dir == ROOT:
    # invoked from root build dir
    if len(COMMAND_LINE_TARGETS) != 0:
        # easy: use specified targets as is
        my_targets = COMMAND_LINE_TARGETS
    else:
        # default target (ALPHA_SE/m5.debug, unless overridden)
        target = os.path.join(default_config, default_binary)
        my_targets = [target]
        Default(target)
else:
    # invoked from subdirectory
    if not launch_dir.startswith(ROOT):
        print "Error: launch dir (%s) not a subdirectory of ROOT (%s)!" \
              (launch_dir, ROOT)
        sys.exit(1)
    # make launch_dir relative to ROOT (strip ROOT plus slash off front)
    launch_dir = launch_dir[len(ROOT)+1:]
    if len(COMMAND_LINE_TARGETS) != 0:
        # make specified targets relative to ROOT
        my_targets = map(lambda x: os.path.join(launch_dir, x),
                         COMMAND_LINE_TARGETS)
    else:
        # build default binary (m5.debug, unless overridden) using the
        # config inferred by the invocation directory (the first
        # subdirectory after ROOT)
        target = os.path.join(launch_dir.split('/')[0], default_binary)
        my_targets = [target]
        Default(target)

# Normalize target paths (gets rid of '..' in the middle, etc.)
my_targets = map(os.path.normpath, my_targets)

# Generate a list of the unique configs that the collected targets reference.
build_dirs = []
for t in my_targets:
    dir = t.split('/')[0]
    if dir not in build_dirs:
        build_dirs.append(dir)

###################################################
#
# Set up the default build environment.  This environment is copied
# and modified according to each selected configuration.
#
###################################################

default_env = Environment(ENV = os.environ,  # inherit user's enviroment vars
                          ROOT = ROOT,
                          SRCDIR = SRCDIR,
                          EXT_SRCDIR = EXT_SRCDIR,
                          CPPDEFINES = [],
                          FULL_SYSTEM = False,
                          ALPHA_TLASER = False,
                          USE_MYSQL = False)

default_env.SConsignFile("sconsign")

# For some reason, the CC and CXX variables don't get passed into the
# environment correctly.  This is probably some sort of scons bug that
# will eventually be fixed.
if os.environ.has_key('CC'):
    default_env.Replace(CC=os.environ['CC'])

if os.environ.has_key('CXX'):
    default_env.Replace(CXX=os.environ['CXX'])

# M5_EXT is used by isa_parser.py to find the PLY package.
default_env.Append(ENV = { 'M5_EXT' : EXT_SRCDIR })

default_env.Append(CCFLAGS='-pipe')
default_env.Append(CCFLAGS='-fno-strict-aliasing')
default_env.Append(CCFLAGS=Split('-Wall -Wno-sign-compare -Werror -Wundef'))
default_env.Append(CPPPATH=[os.path.join(EXT_SRCDIR + '/dnet')])

# libelf build is described in its own SConscript file.  Using a
# dictionary for exports lets us export "default_env" so the
# SConscript will see it as "env".  SConscript-global is the build in
# build/libelf shared among all configs.
default_env.SConscript('m5/libelf/SConscript-global',
                       exports={'env' : default_env})

###################################################
#
# Define build environments for selected configurations.
#
###################################################

for build_dir in build_dirs:
    # Make a copy of the default environment to use for this config.
    env = default_env.Copy()
    # Modify 'env' according to the build directory config.
    print "Configuring options for directory '%s'." % build_dir
    if not set_dir_options(build_dir, env):
        print "Skipping directory '%s'." % build_dir
        continue

    # The m5/SConscript file sets up the build rules in 'env' according
    # to the configured options.
    SConscript('m5/SConscript', build_dir = build_dir, exports = 'env',
               duplicate=0)


###################################################
#
# Let SCons do its thing.  At this point SCons will use the defined
# build environments to build the requested targets.
#
###################################################