impl bytes index and ipairs

1 files changed, 116 insertions, 7 deletions

diff --git a/xmake/core/base/bytes.lua b/xmake/core/base/bytes.lua
index 38f79c324..9f5a9ead2 100644
--- a/xmake/core/base/bytes.lua
+++ b/xmake/core/base/bytes.lua
@@ -23,21 +23,130 @@ local bytes = bytes or {}
 local _instance = _instance or {}
 
 -- load modules
-local bit       = require('bit')
-local ffi       = require('ffi')
-local string    = require("base/string")
+local bit = require('bit')
+local ffi = require('ffi')
+local os  = require("base/os")
+
+-- define ffi interfaces
+ffi.cdef[[
+    void* malloc(size_t __size);
+    void  free(void *__ptr);
+]]
 
 -- new a bytes instance
-function _instance.new(size)
-    local instance   = table.inherit(_instance)
+--
+-- new(size): allocates a buffer of given size
+-- new(size, ptr [, manage]) : mounts buffer on existing storage (manage memory or not)
+-- new(str): allocates a buffer from the given string
+--
+function _instance.new(arg1, arg2, arg3)
+    local instance = table.inherit(_instance)
+    if type(arg1) == "number" then
+        local size = arg1
+        local ptr = arg2 
+        if ptr then
+            -- new(size, ptr [, manage]) : mounts buffer on existing storage (manage memory or not)
+            local manage = arg3
+            if manage then
+                instance._CDATA   = ffi.gc(ffi.cast("unsigned char*", ptr), ffi.C.free)
+                instance._MANAGED = true
+            else
+                instance._CDATA   = ffi.cast("unsigned char*", ptr)
+                instance._MANAGED = false
+            end
+        else
+            -- new(size): allocates a buffer of given size
+            ptr = ffi.C.malloc(size)
+            instance._CDATA   = ffi.gc(ffi.cast("unsigned char*", ptr), ffi.C.free)
+            instance._MANAGED = true
+        end
+        instance._SIZE   = size
+    elseif type(arg1) == "string" then
+        -- new(str): allocates a buffer from the given string
+        local str = arg1
+        instance._SIZE    = #str
+        instance._CDATA   = ffi.cast("unsigned char*", str)
+        instance._REF     = str -- keep ref for GC
+        instance._MANAGED = false
+    else
+        os.raise("invalid arguments for bytes(...)!")
+    end
     setmetatable(instance, _instance)
     return instance
 end
 
--- new an instance
-function bytes.new(str_or_size)
+-- get bytes size
+function _instance:size()
+    return self._SIZE
+end
 
+-- bytes:ipairs()
+function _instance:ipairs()
+    local index = 0
+    return function (...)
+        if index < self:size() then
+            index = index + 1
+            return index, self[index]
+        end
+    end
 end
 
+-- bytes[key]
+function _instance:__index(key)
+    if type(key) == "number" then
+        if key < 1 or key > self:size() then 
+            os.raise("bytes index(%d/%d) out of bounds!", key, self:size()) 
+        end
+        return self._CDATA[key - 1]
+    --[[
+    elseif type(key) == "table" then
+        local start, last = key[1], key[2]
+        return self:slice(start, last)
+    --]]
+    end
+    return rawget(self, key)
+end
+
+-- bytes[key] = value
+function _instance:__newindex(key, value)
+    if type(key) == "number" then
+        if key < 1 or key > self:size() then 
+            os.raise("bytes index(%d/%d) out of bounds!", key, self:size()) 
+        end
+        self._CDATA[key - 1] = value
+        return
+        --[[
+    elseif type(key) == "table" then
+        local start,last = key[1],key[2]
+        self:slice(start,last):copy(value)
+        return]]
+    end
+    rawset(self, key, value)
+end
+
+-- tostring(bytes)
+function _instance:__tostring()
+    local parts = {}
+    for i = 1, tonumber(self:size()) do
+        parts[i] = bit.tohex(self[i], 2)
+    end
+    return "<bytes: " .. table.concat(parts, " ") .. ">"
+end
+
+-- new an bytes instance
+function bytes.new(...)
+    return _instance.new(...)
+end
+
+-- register call function
+setmetatable(bytes, {
+    __call = function (_, ...) 
+        return bytes.new(...) 
+    end,
+    __tostring = function()
+        return "<bytes>"
+    end
+})
+
 -- return module: bytes
 return bytes