patterns: Added SWF header pattern (#219)

* patterns: Added pattern for SWF files.

* Added test file for SWF header.

* Update README with SWF file type.

README.md

@@ -101,6 +101,7 @@ Everything will immediately show up in ImHex's Content Store and gets bundled wi
 | SPIRV | | [`patterns/spirv.hexpat`](patterns/spirv.hexpat) | SPIR-V header and instructions |
 | STL | `model/stl` | [`patterns/stl.hexpat`](patterns/stl.hexpat) | STL 3D Model format |
 | StuffItV5 | `application/x-stuffit` | [`patterns/sit5.hexpat`](patterns/sit5.hexpat) | StuffIt V5 archive |
+| SWF | |[`patterns/swf.hexpat`](patterns/swf.hexpat) | Shockwave Flash file format |
 | TAR | `application/x-tar` | [`patterns/tar.hexpat`](patterns/tar.hexpat) | Tar file format |
 | TIFF | `image/tiff` | [`patterns/tiff.hexpat`](patterns/tiff.hexpat) | Tag Image File Format |
 | TGA | `image/tga` | [`patterns/tga.hexpat`](patterns/tga.hexpat) | Truevision TGA/TARGA image |

patterns/swf.hexpat

@@ -0,0 +1,29 @@
+#pragma author saturnaliam
+#pragma description SWF file header
+#pragma endian little
+#include <type/magic.pat>
+
+
+// RECTs are more complicated, but for the header,
+// this works fine.
+bitfield Rect {
+    nSize : 5 [[name("N Size")]];
+    signed xMin : 15 [[name("X Min")]];
+    signed xMax : 15 [[name("X Max")]];
+    signed yMin : 15 [[name("Y Min")]];
+    signed yMax : 15 [[name("Y Max")]];
+};
+
+
+struct Header {
+    char compressionSignature [[name("Compression"), comment("F - Uncompressed\nC - zlib Compressed\nZ - LZMA compressed")]];
+    type::Magic<"WS"> signature [[name("Signature")]];
+    u8 swfVersion [[name("SWF Version")]];
+    u32 bytesSize [[name("Uncompressed Size")]];
+    be Rect rect [[name("Frame Size"), comment("Needs to be uncompressed to have the correct value.")]];
+    padding[1];
+    u8 frameRate [[name("Framerate"), comment("Needs to be uncompressed to have the correct value.")]];
+    u16 frameCount [[name("Frame Count"), comment("Needs to be uncompressed to have the correct value.")]];
+};
+
+Header header @ 0x00;