add xml module

1 files changed, 268 insertions, 0 deletions

diff --git a/xmake/core/base/xml.lua b/xmake/core/base/xml.lua
new file mode 100644
index 000000000..7ac12f133
--- /dev/null
+++ b/xmake/core/base/xml.lua
@@ -0,0 +1,268 @@
+--!A cross-platform build utility based on Lua
+--
+-- 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.
+--
+-- Copyright (C) 2015-present, Xmake Open Source Community.
+--
+-- @author      ruki
+-- @file        xml.lua
+--
+
+-- define module: xml
+local xml = xml or {}
+
+-- load modules
+local io    = require("base/io")
+local os    = require("base/os")
+local table = require("base/table")
+
+function xml._decode_entities(str)
+    return (str:gsub("&lt;", "<")
+               :gsub("&gt;", ">")
+               :gsub("&apos;", "'")
+               :gsub("&quot;", "\"")
+               :gsub("&amp;", "&"))
+end
+
+function xml._encode_text(str)
+    return (str:gsub("&", "&amp;")
+               :gsub("<", "&lt;")
+               :gsub(">", "&gt;"))
+end
+
+function xml._encode_attr(str)
+    return xml._encode_text(str):gsub("\"", "&quot;")
+end
+
+function xml._parse_attrs(attrstr)
+    local attrs = {}
+    attrstr:gsub("([%w_:%-%.]+)%s*=%s*([\"'])(.-)%2", function(key, quote, value)
+        attrs[key] = xml._decode_entities(value)
+    end)
+    return attrs
+end
+
+-- create an xml element node
+function xml.new(name, attrs, children)
+    return {
+        name = name,
+        attrs = attrs or {},
+        children = children or {}
+    }
+end
+
+-- create a text node
+function xml.text(value)
+    return {type = "text", text = value or ""}
+end
+
+function xml._append_text(stack, text, opt)
+    opt = opt or {}
+    if opt.trim_text ~= false then
+        text = text:gsub("^%s+", ""):gsub("%s+$", "")
+    end
+    if text ~= "" then
+        local top = stack[#stack]
+        top.children = top.children or {}
+        table.insert(top.children, {type = "text", text = xml._decode_entities(text)})
+    end
+end
+
+function xml._handle_closing(stack, tagname)
+    local top = stack[#stack]
+    if not top or top.name ~= tagname then
+        return nil, string.format("malformed xml: unexpected closing </%s>", tagname)
+    end
+    table.remove(stack)
+    return true
+end
+
+-- decode xml string to tree node(s)
+function xml.decode(data, opt)
+    opt = opt or {}
+    local root = {name = "__root__", attrs = {}, children = {}}
+    local stack = {root}
+    local i = 1
+    local len = #data
+    while i <= len do
+        local lt = data:find("<", i, true)
+        if not lt then
+            local text = data:sub(i)
+            xml._append_text(stack, text, opt)
+            break
+        end
+        if lt > i then
+            local text = data:sub(i, lt - 1)
+            xml._append_text(stack, text, opt)
+        end
+        if data:sub(lt + 1, lt + 3) == "!--" then
+            local close = data:find("-->", lt + 4, true)
+            if not close then
+                return nil, "unterminated xml comment"
+            end
+            i = close + 3
+        elseif data:sub(lt + 1, lt + 1) == "?" then
+            local close = data:find("?>", lt + 2, true)
+            if not close then
+                return nil, "unterminated xml declaration"
+            end
+            i = close + 2
+        elseif data:sub(lt + 1, lt + 1) == "!" then
+            local close = data:find(">", lt + 2)
+            if not close then
+                return nil, "unterminated xml declaration"
+            end
+            i = close + 1
+        elseif data:sub(lt + 1, lt + 1) == "/" then
+            local close = data:find(">", lt + 1)
+            if not close then
+                return nil, "unterminated closing tag"
+            end
+            local tagname = data:sub(lt + 2, close - 1):match("^%s*([^%s>]+)")
+            local ok, err = xml._handle_closing(stack, tagname)
+            if not ok then
+                return nil, err
+            end
+            i = close + 1
+        else
+            local close = data:find(">", lt + 1)
+            if not close then
+                return nil, "unterminated opening tag"
+            end
+            local inside = data:sub(lt + 1, close - 1)
+            local selfclose = inside:find("/%s*$")
+            if selfclose then
+                inside = inside:gsub("/%s*$", "")
+            end
+            local tagname, attrstr = inside:match("^%s*([^%s>]+)%s*(.-)%s*$")
+            local attrs = xml._parse_attrs(attrstr or "")
+            local node = {name = tagname, attrs = attrs, children = {}}
+            local top = stack[#stack]
+            top.children = top.children or {}
+            table.insert(top.children, node)
+            if not selfclose then
+                table.insert(stack, node)
+            end
+            i = close + 1
+        end
+    end
+    if #stack ~= 1 then
+        return nil, "malformed xml: unclosed tags"
+    end
+    if #root.children == 1 then
+        return root.children[1]
+    end
+    return root.children
+end
+
+function xml._indent(opt, level)
+    if not opt.pretty then
+        return ""
+    end
+    local indent = opt.indent or 4
+    local indentchar = opt.indentchar or " "
+    if type(indent) == "number" then
+        return string.rep(indentchar, indent * level)
+    end
+    return indent:rep(level)
+end
+
+function xml._encode_node(node, opt, level)
+    opt = opt or {}
+    level = level or 0
+    if node.type == "text" then
+        local indent = xml._indent(opt, level)
+        local text = xml._encode_text(tostring(node.text or ""))
+        if opt.pretty then
+            return indent .. text
+        end
+        return text
+    end
+    local attrs = {}
+    for k, v in pairs(node.attrs or {}) do
+        table.insert(attrs, string.format('%s="%s"', k, xml._encode_attr(tostring(v))))
+    end
+    table.sort(attrs)
+    local open = "<" .. node.name
+    if #attrs > 0 then
+        open = open .. " " .. table.concat(attrs, " ")
+    end
+    if not node.children or #node.children == 0 then
+        return xml._indent(opt, level) .. open .. "/>"
+    end
+    local newline = opt.pretty and "\n" or ""
+    if #node.children == 1 and node.children[1].type == "text" then
+        local text = xml._encode_text(tostring(node.children[1].text or ""))
+        return string.format("%s%s>%s</%s>", xml._indent(opt, level), open, text, node.name)
+    end
+    local result = {}
+    table.insert(result, xml._indent(opt, level) .. open .. ">")
+    for _, child in ipairs(node.children) do
+        table.insert(result, xml._encode_node(child, opt, level + 1))
+    end
+    table.insert(result, xml._indent(opt, level) .. "</" .. node.name .. ">")
+    return table.concat(result, newline ~= "" and newline or "")
+end
+
+-- encode xml node to string
+function xml.encode(node, opt)
+    opt = opt or {}
+    return xml._encode_node(node, opt, 0)
+end
+
+-- load xml file
+function xml.load(filepath, opt)
+    local data, err = io.readfile(filepath, opt)
+    if not data then
+        return nil, err
+    end
+    return xml.decode(data, opt)
+end
+
+-- save xml node to file
+function xml.save(filepath, node, opt)
+    local data = xml.encode(node, opt)
+    if not data then
+        return nil, "failed to encode xml"
+    end
+    return io.writefile(filepath, data, opt)
+end
+
+-- find the first child node with the given name
+function xml.find(node, name)
+    if not node or not node.children then
+        return nil
+    end
+    for _, child in ipairs(node.children) do
+        if child.name == name then
+            return child
+        end
+    end
+end
+
+-- get concatenated text from child nodes
+function xml.text_of(node)
+    if not node or not node.children then
+        return ""
+    end
+    local buffer = {}
+    for _, child in ipairs(node.children) do
+        if child.type == "text" then
+            table.insert(buffer, child.text)
+        end
+    end
+    return table.concat(buffer, "")
+end
+
+return xml
+