From 5462c4ef4fb470c5878a46cb809203fc1459998f Mon Sep 17 00:00:00 2001
From: carllu <carllu@tencent.com>
Date: Fri, 5 Apr 2019 22:38:59 +0800
Subject: [PATCH] Add support to export compile_flags.txt

---
 xmake/plugins/project/clang/compile_flags.lua | 126 ++++++++++++++++++
 xmake/plugins/project/main.lua                |   2 +
 xmake/plugins/project/xmake.lua               |   1 +
 3 files changed, 129 insertions(+)
 create mode 100644 xmake/plugins/project/clang/compile_flags.lua

diff --git a/xmake/plugins/project/clang/compile_flags.lua b/xmake/plugins/project/clang/compile_flags.lua
new file mode 100644
index 00000000000..78e85e0b446
--- /dev/null
+++ b/xmake/plugins/project/clang/compile_flags.lua
@@ -0,0 +1,126 @@
+--!A cross-platform build utility based on Lua
+--
+-- Licensed to the Apache Software Foundation (ASF) under one
+-- or more contributor license agreements.  See the NOTICE file
+-- distributed with this work for additional information
+-- regarding copyright ownership.  The ASF licenses this file
+-- to you 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.
+-- 
+-- Copyright (C) 2015 - 2019, TBOOX Open Source Group.
+--
+-- @author      luzhlon
+-- @file        compile_flags.lua
+--
+
+-- imports
+import("core.tool.compiler")
+import("core.project.project")
+import("core.language.language")
+
+-- make the object
+function _make_object(target, sourcefile, objectfile)
+
+    -- get the source file kind
+    local sourcekind = language.sourcekind_of(sourcefile)
+
+    -- make the object for the *.o/obj? ignore it directly
+    if sourcekind == "obj" or sourcekind == "lib" then
+        return
+    end
+
+    -- get compile arguments
+    local arguments = compiler.compflags(sourcefile, {target = target})
+    for i, flag in ipairs(arguments) do
+        -- only export the -I*/-D* flags
+        if not g_flags[flag] and string.find(flag, '^-[ID]') then
+            g_flags[flag] = true
+            table.insert(g_flags, flag)
+        end
+    end
+
+    -- clear first line marks
+    _g.firstline = false
+end
+ 
+-- make each objects
+function _make_each_objects(target, sourcekind, sourcebatch)
+    for index, objectfile in ipairs(sourcebatch.objectfiles) do
+        _make_object(target, sourcebatch.sourcefiles[index], objectfile)
+    end
+end
+ 
+-- make single object
+function _make_single_object(target, sourcekind, sourcebatch)
+
+    -- not supported now, ignore it directly
+    for _, sourcefile in ipairs(table.wrap(sourcebatch.sourcefiles)) do
+        cprint("${bright yellow}warning: ${default yellow}ignore[%s]: %s", target:name(), sourcefile)
+    end
+end
+
+-- make target
+function _make_target(target)
+
+    -- TODO
+    -- disable precompiled header first
+    target:set("pcheader", nil)
+    target:set("pcxxheader", nil)
+
+    -- build source batches
+    for sourcekind, sourcebatch in pairs(target:sourcebatches()) do
+        if not sourcebatch.rulename then
+            if type(sourcebatch.objectfiles) == "string" then
+                _make_single_object(target, sourcekind, sourcebatch)
+            else
+                _make_each_objects(target, sourcekind, sourcebatch)
+            end
+        end
+    end
+end
+
+-- make all
+function _make_all()
+    -- make flags
+    _g.firstline = true
+    for _, target in pairs(project.targets()) do
+        local isdefault = target:get("default")
+        if not target:isphony() and (isdefault == nil or isdefault == true) then
+            _make_target(target)
+        end
+    end
+end
+
+-- generate compilation databases for clang-based tools(compile_flags.txt)
+--
+-- references:
+--  - https://clang.llvm.org/docs/JSONCompilationDatabase.html
+--
+function make(outputdir)
+
+    -- enter project directory
+    local oldir = os.cd(os.projectdir())
+
+    -- make all
+    g_flags = {}
+    _make_all()
+
+    -- write to file
+    local flagfile = io.open(path.join(outputdir, "compile_flags.txt"), "w")
+    for i, flag in ipairs(g_flags) do
+        flagfile:write(flag, '\n')
+    end
+    flagfile:close()
+ 
+    -- leave project directory
+    os.cd(oldir)
+end
diff --git a/xmake/plugins/project/main.lua b/xmake/plugins/project/main.lua
index fc55fd4a1d8..82fde03d8d7 100755
--- a/xmake/plugins/project/main.lua
+++ b/xmake/plugins/project/main.lua
@@ -38,6 +38,7 @@ import("vstudio.vs2013")
 import("vstudio.vs2015")
 import("vstudio.vs2017")
 import("vstudio.vs2019")
+import("clang.compile_flags")
 import("clang.compile_commands")
 
 -- make project
@@ -58,6 +59,7 @@ function _make(kind)
     ,   vs2015           = vs2015.make
     ,   vs2017           = vs2017.make
     ,   vs2019           = vs2019.make
+    ,   compile_flags = compile_flags.make
     ,   compile_commands = compile_commands.make
     }
     assert(maps[kind], "the project kind(%s) is not supported!", kind)
diff --git a/xmake/plugins/project/xmake.lua b/xmake/plugins/project/xmake.lua
index 78074567ed3..1d1fae16009 100644
--- a/xmake/plugins/project/xmake.lua
+++ b/xmake/plugins/project/xmake.lua
@@ -44,6 +44,7 @@ task("project")
                 {
                     {'k', "kind",      "kv", "makefile",    "Set the project kind." 
                                                        ,    "    - makefile"
+                                                       ,    "    - compile_flags"
                                                        ,    "    - compile_commands (clang compilation database with json format)"
                                                        ,    "    - vs2002, vs2003, vs2005, vs2008, vs2010, vs2012, vs2013, vs2015, vs2017" }
                 ,   {'m', "modes",     "kv", nil,           "Set the project modes."