Fix endianess handling for streams

Inochi2D · Oct 9, 2024 · c73e820 · c73e820
1 parent 52cc5db
commit c73e820
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Showing 3 changed files with 73 additions and 21 deletions.
diff --git a/source/numem/io/endian.d b/source/numem/io/endian.d
@@ -8,6 +8,8 @@ module numem.io.endian;
 import numem.core;
 import numem.collections.vector;
 import std.traits : isNumeric, isIntegral, isBasicType;
+import std.traits : Unqual;
+import std.bitmanip;
 
 @nogc nothrow:
 
@@ -58,21 +60,21 @@ private {
 */
 @trusted
 ubyte[T.sizeof] toEndian(T)(T value, Endianess endianness) {
+    union tmp {
+        Unqual!T value;
+        ubyte[T.sizeof] bytes;
+    }
 
-    // Get bytes from value
-    ubyte[T.sizeof] output;
-    output = (cast(ubyte*)&value)[0..T.sizeof];
+    tmp tmp_;
+    tmp_.value = value;
 
     // Swap endianness if neccesary
     if (endianness != NATIVE_ENDIAN) {
-        ubyte[T.sizeof] tmp;
-        static foreach (i; 0..T.sizeof) {
-            tmp[i] = output[(T.sizeof-1)-i];
-        }
-        output = tmp;
+        ubyte[] slice = tmp_.bytes[0..$];
+        swapEndian(slice);
     }
 
-    return output;
+    return tmp_.bytes;
 }
 
 /**
@@ -88,9 +90,9 @@ T toEndianReinterpret(T)(T in_, Endianess endianness) {
             ubyte[T.sizeof] bytes;
         }
 
-        tmp toConvert;
-        toConvert.bytes = toEndian!T(in_, endianness);
-        return toConvert.value;
+        tmp tmp_;
+        tmp_.bytes = toEndian!T(in_, endianness);
+        return tmp_.value;
     }
 
     return in_;
@@ -107,13 +109,14 @@ T fromEndian(T)(ubyte[] value, Endianess endianness) if (isBasicType!T) {
         T value;
         ubyte[T.sizeof] bytes;
     }
-    tmp toConvert;
-    toConvert.bytes = value;
+    tmp tmp_;
+    tmp_.bytes = value;
+    ubyte[] slice = tmp_.bytes[0..$];
 
     if (endianness != NATIVE_ENDIAN) 
-        swapEndian(value);
+        swapEndian(slice);
 
-    return toConvert.value;
+    return tmp_.value;
 }
 
 /**
@@ -130,9 +133,10 @@ T fromEndianReinterpret(T)(ubyte[] value, Endianess endianness) {
     }
     tmp toConvert;
     toConvert.bytes = value;
+    ubyte[] slice = tmp_.bytes[0..$];
 
     if (endianness != NATIVE_ENDIAN) 
-        swapEndian(value);
+        swapEndian(slice);
 
     return toConvert.value;
 }

diff --git a/source/numem/io/stream/reader.d b/source/numem/io/stream/reader.d
@@ -86,7 +86,7 @@ public:
         static if (is(T.valueType == ubyte)) {
             r += stream.read(val, 0, length);
         } else {
-            T tmp;
+            T.valueType tmp;
             foreach(i; 0..length) {
                 int ir = this.read!(T.valueType)(tmp);
                 if (ir < 0) 

diff --git a/source/numem/io/stream/writer.d b/source/numem/io/stream/writer.d
@@ -39,7 +39,6 @@ public:
             stream.write(toWrite);
         } else {
             ubyte[1] tmp = [cast(ubyte)val];
-
             stream.write(tmp[]);
         }
     }
@@ -53,8 +52,12 @@ public:
     /// Ditto
     @trusted
     void write(T)(T val) if (isSomeVector!T) {
-        foreach(element; val) {
-            this.write!(T.valueType)(element);
+        static if (T.valueType.sizeof == 1) {
+            stream.write(cast(ubyte[])val[0..$]);
+        } else {
+            foreach(element; val) {
+                this.write!(T.valueType)(element);
+            }
         }
     }
 
@@ -81,4 +84,49 @@ unittest {
 
     assert(buffer[0] == 100);
     assert(buffer[99] == 1);
+}
+
+@("RW: Little Endian")
+unittest {
+    import numem.io.stream.memstream : MemoryStream;
+    import numem.io.stream.reader : StreamReader;
+    alias TestReader = StreamReader!(Endianess.littleEndian);
+    alias TestWriter = StreamWriter!(Endianess.littleEndian);
+
+    ubyte[8] buffer;
+    auto stream = new MemoryStream(buffer.ptr, buffer.length);
+    auto writer = new TestWriter(stream);
+    auto reader = new TestReader(stream);
+
+    enum MAGIC = 0xFF00FF0F;
+
+    writer.write!ulong(MAGIC);
+    stream.seek(0);
+
+    ulong val;
+    reader.read!ulong(val);
+
+    assert(val == MAGIC);
+}
+
+@("RW: Big Endian")
+unittest {
+    import numem.io.stream.memstream : MemoryStream;
+    import numem.io.stream.reader : StreamReader;
+    alias TestReader = StreamReader!(Endianess.bigEndian);
+    alias TestWriter = StreamWriter!(Endianess.bigEndian);
+
+    ubyte[8] buffer;
+    auto stream = new MemoryStream(buffer.ptr, buffer.length);
+    auto writer = new TestWriter(stream);
+    auto reader = new TestReader(stream);
+
+    enum MAGIC = 0xFF00FF0F;
+
+    writer.write!ulong(MAGIC);
+    stream.seek(0);
+
+    ulong val;
+    reader.read!ulong(val);
+    assert(val == MAGIC);
 }