improve build dependence

1 files changed, 94 insertions, 0 deletions

diff --git a/xmake/modules/core/project/depend.lua b/xmake/modules/core/project/depend.lua
new file mode 100644
index 000000000..cbb3d1bd8
--- /dev/null
+++ b/xmake/modules/core/project/depend.lua
@@ -0,0 +1,94 @@
+--!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 - 2018, TBOOX Open Source Group.
+--
+-- @author      ruki
+-- @file        depend.lua
+--
+
+-- load dependent info from the given file (.d) 
+function load(dependfile)
+    return os.isfile(dependfile) and io.load(dependfile) or nil
+end
+
+-- save dependent info to file
+function save(dependinfo, dependfile)
+    io.save(dependfile, dependinfo)
+end
+
+-- the dependent info is changed?
+--
+-- if not depend.is_changed(dependinfo, {filemtime = os.mtime(objectfile), values = {...}}) then
+--      return 
+-- end
+--
+function is_changed(dependinfo, opt)
+
+    -- check the dependent files are changed?
+    local lastmtime = nil
+    _g.file_results = _g.file_results or {}
+    for _, file in ipairs(dependinfo.files) do
+
+        -- optimization: this file has been not checked?
+        local status = _g.file_results[file]
+        if status == nil then
+
+            -- optimization: only uses the mtime of first object file
+            lastmtime = lastmtime or opt.lastmtime or 0
+
+            -- source and header files have been changed?
+            if os.mtime(file) > lastmtime then
+
+                -- mark this file as changed
+                _g.file_results[file] = true
+                return true
+            end
+
+            -- mark this file as not changed
+            _g.file_results[file] = false
+        
+        -- has been checked and changed?
+        elseif status then
+            return true
+        end
+    end
+
+    -- check the dependent values are changed?
+    local depvalues = dependinfo.values or {}
+    local optvalues = opt.values or {}
+    if #depvalues ~= #optvalues then
+        return true
+    end
+    for idx, depvalue in ipairs(depvalues) do
+        local optvalue = optvalues[idx]
+        local deptype = type(depvalue) 
+        local opttype = type(optvalue)
+        if deptype ~= opttype then
+            return true
+        elseif deptype == "string" and depvalue ~= optvalue then
+            return true
+        elseif deptype == "table" then
+            for subidx, subvalue in ipairs(depvalue) do
+                if subvalue ~= optvalue[subidx] then
+                    return true
+                end
+            end
+        end
+    end
+end