# Copyright (c) 2013 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

# TODO(brettw) Use "gcc_toolchain.gni" like the Linux toolchains. This requires
# some enhancements since the commands on Mac are slightly different than on
# Linux.

import("../goma.gni")
import("//build/config/mac/mac_sdk.gni")

assert(host_os == "mac")

import("//build/toolchain/clang.gni")
import("//build/toolchain/goma.gni")
import("//build/config/sysroot.gni")

if (use_goma) {
  goma_prefix = "$goma_dir/gomacc "
} else {
  goma_prefix = ""
}

# Shared toolchain definition. Invocations should set toolchain_os to set the
# build args in this definition.
template("mac_toolchain") {
  toolchain(target_name) {
    assert(defined(invoker.cc), "mac_toolchain() must specify a \"cc\" value")
    assert(defined(invoker.cxx), "mac_toolchain() must specify a \"cxx\" value")
    assert(defined(invoker.ar), "mac_toolchain() must specify an \"ar\" value")
    assert(defined(invoker.ld), "mac_toolchain() must specify a \"ld\" value")
    assert(defined(invoker.toolchain_cpu),
           "mac_toolchain() must specify a \"toolchain_cpu\"")
    assert(defined(invoker.toolchain_os),
           "mac_toolchain() must specify a \"toolchain_os\"")

    # We can't do string interpolation ($ in strings) on things with dots in
    # them. To allow us to use $cc below, for example, we create copies of
    # these values in our scope.
    cc = invoker.cc
    cxx = invoker.cxx
    ar = invoker.ar
    ld = invoker.ld

    # Make these apply to all tools below.
    lib_switch = "-l"
    lib_dir_switch = "-L"

    sysroot_flags = ""

    if (defined(invoker.sysroot_flags)) {
      sysroot_flags = invoker.sysroot_flags
    }

    toolchain_flags = ""
    if (invoker.toolchain_cpu == "i386") {
      toolchain_flags = "-m32"
    }

    tool("cc") {
      depfile = "{{output}}.d"
      command = "$cc -MMD -MF $depfile {{defines}} {{include_dirs}} $sysroot_flags $toolchain_flags {{cflags}} {{cflags_c}} -c {{source}} -o {{output}}"
      depsformat = "gcc"
      description = "CC {{output}}"
      outputs = [
        "{{target_out_dir}}/{{target_output_name}}/{{source_name_part}}.o",
      ]
    }

    tool("cxx") {
      depfile = "{{output}}.d"
      command = "$cxx -MMD -MF $depfile {{defines}} {{include_dirs}} $sysroot_flags $toolchain_flags {{cflags}} {{cflags_cc}} -c {{source}} -o {{output}}"
      depsformat = "gcc"
      description = "CXX {{output}}"
      outputs = [
        "{{target_out_dir}}/{{target_output_name}}/{{source_name_part}}.o",
      ]
    }

    tool("asm") {
      # For GCC we can just use the C compiler to compile assembly.
      depfile = "{{output}}.d"
      command = "$cc -MMD -MF $depfile {{defines}} {{include_dirs}} $sysroot_flags $toolchain_flags {{asmflags}} -c {{source}} -o {{output}}"
      depsformat = "gcc"
      description = "ASM {{output}}"
      outputs = [
        "{{target_out_dir}}/{{target_output_name}}/{{source_name_part}}.o",
      ]
    }

    tool("objc") {
      depfile = "{{output}}.d"
      command = "$cxx -MMD -MF $depfile {{defines}} {{include_dirs}} $sysroot_flags $toolchain_flags {{cflags}} {{cflags_c}} {{cflags_objc}} -c {{source}} -o {{output}}"
      depsformat = "gcc"
      description = "OBJC {{output}}"
      outputs = [
        "{{target_out_dir}}/{{target_output_name}}/{{source_name_part}}.o",
      ]
    }

    tool("objcxx") {
      depfile = "{{output}}.d"
      command = "$cxx -MMD -MF $depfile {{defines}} {{include_dirs}} $sysroot_flags $toolchain_flags {{cflags}} {{cflags_cc}} {{cflags_objcc}} -c {{source}} -o {{output}}"
      depsformat = "gcc"
      description = "OBJCXX {{output}}"
      outputs = [
        "{{target_out_dir}}/{{target_output_name}}/{{source_name_part}}.o",
      ]
    }

    tool("alink") {
      rspfile = "{{output}}.rsp"
      command = "rm -f {{output}} && $ar rcs {{output}} @$rspfile"
      description = "AR {{output}}"
      rspfile_content = "{{inputs}}"
      outputs = [
        "{{target_out_dir}}/{{target_output_name}}{{output_extension}}",
      ]
      default_output_extension = ".a"
      output_prefix = "lib"
    }

    tool("solink") {
      dylib = "{{root_out_dir}}/{{target_output_name}}{{output_extension}}"  # eg "./libfoo.dylib"
      rspfile = dylib + ".rsp"

      # These variables are not build into GN but are helpers that implement
      # (1) linking to produce a .so, (2) extracting the symbols from that file
      # to a temporary file, (3) if the temporary file has differences from the
      # existing .TOC file, overwrite it, oterwise, don't change it.
      #
      # As a special case, if the library reexports symbols from other dynamic
      # libraries, we always update the .TOC and skip the temporary file and
      # diffing steps, since that library always needs to be re-linked.
      tocname = dylib + ".TOC"
      temporary_tocname = dylib + ".tmp"

      does_reexport_command = "[ ! -e $dylib -o ! -e $tocname ] || otool -l $dylib | grep -q LC_REEXPORT_DYLIB"
      link_command = "$ld -shared $sysroot_flags $toolchain_flags {{ldflags}} -o $dylib -Wl,-filelist,$rspfile {{solibs}} {{libs}}"
      replace_command = "if ! cmp -s $temporary_tocname $tocname; then mv $temporary_tocname $tocname"
      extract_toc_command = "{ otool -l $dylib | grep LC_ID_DYLIB -A 5; nm -gP $dylib | cut -f1-2 -d' ' | grep -v U\$\$; true; }"

      command = "if $does_reexport_command ; then $link_command && $extract_toc_command > $tocname; else $link_command && $extract_toc_command > $temporary_tocname && $replace_command ; fi; fi"

      rspfile_content = "{{inputs_newline}}"

      description = "SOLINK {{output}}"

      # Use this for {{output_extension}} expansions unless a target manually
      # overrides it (in which case {{output_extension}} will be what the target
      # specifies).
      default_output_extension = ".dylib"

      output_prefix = "lib"

      # Since the above commands only updates the .TOC file when it changes, ask
      # Ninja to check if the timestamp actually changed to know if downstream
      # dependencies should be recompiled.
      restat = true

      # Tell GN about the output files. It will link to the dylib but use the
      # tocname for dependency management.
      outputs = [
        dylib,
        tocname,
      ]
      link_output = dylib
      depend_output = tocname
    }

    tool("link") {
      exename = "{{target_output_name}}{{output_extension}}"
      outfile = "{{root_out_dir}}/$exename"
      rspfile = "$outfile.rsp"

      if (defined(invoker.strip)) {
        stripped_outfile = "{{root_out_dir}}/exe.stripped/$exename"
      }

      command = "$ld $sysroot_flags $toolchain_flags {{ldflags}} -Xlinker -rpath -Xlinker @executable_path/Frameworks -o $outfile -Wl,-filelist,$rspfile {{solibs}} {{libs}}"
      if (defined(invoker.strip)) {
        strip = invoker.strip
        strip_command = "${strip} -x -o $stripped_outfile $outfile"
        command += " && " + strip_command
      }

      description = "LINK $outfile"
      rspfile_content = "{{inputs_newline}}"
      outputs = [
        outfile,
      ]
      if (defined(invoker.strip)) {
        outputs += [ stripped_outfile ]
      }
    }

    tool("stamp") {
      command = "touch {{output}}"
      description = "STAMP {{output}}"
    }

    tool("copy") {
      command = "ln -f {{source}} {{output}} 2>/dev/null || (rm -rf {{output}} && cp -af {{source}} {{output}})"
      description = "COPY {{source}} {{output}}"
    }

    toolchain_args = {
      current_cpu = invoker.toolchain_cpu
      current_os = invoker.toolchain_os

      # These values need to be passed through unchanged.
      target_os = target_os
      target_cpu = target_cpu

      if (defined(invoker.is_clang)) {
        is_clang = invoker.is_clang
      }
    }
  }
}

# Toolchain used for Mac host targets.
mac_toolchain("clang_x64") {
  toolchain_cpu = "x64"
  toolchain_os = "mac"
  prefix = rebase_path("//buildtools/mac-x64/clang/bin", root_build_dir)
  cc = "${goma_prefix}$prefix/clang"
  cxx = "${goma_prefix}$prefix/clang++"
  ar = "${prefix}/llvm-ar"
  ld = cxx
  strip = "strip"
  is_clang = true
  sysroot_flags = "-isysroot $mac_sdk_path -mmacosx-version-min=$mac_sdk_min"
}

# Toolchain used for Mac host (i386) targets.
mac_toolchain("clang_x86") {
  toolchain_cpu = "i386"
  toolchain_os = "mac"
  prefix = rebase_path("//buildtools/mac-x64/clang/bin", root_build_dir)
  cc = "${goma_prefix}$prefix/clang"
  cxx = "${goma_prefix}$prefix/clang++"
  ar = "${prefix}/llvm-ar"
  ld = cxx
  strip = "strip"
  is_clang = true
  sysroot_flags = "-isysroot $mac_sdk_path -mmacosx-version-min=$mac_sdk_min"
}