patterns: Added support for GNU MO files (#383)

Author: dvob

README.md

@@ -105,6 +105,7 @@ Everything will immediately show up in ImHex's Content Store and gets bundled wi
 | MBR & GPT | | [`patterns/partition_table.hexpat`](patterns/partition_table.hexpat) | Partition tables with primary focus on GPT |
 | MIDI | `audio/midi` | [`patterns/midi.hexpat`](patterns/midi.hexpat) | MIDI header, event fields provided |
 | MiniDump | `application/x-dmp` | [`patterns/minidump.hexpat`](patterns/minidump.hexpat) | Windows MiniDump files |
+| MO | | [`patterns/mo.hexpat`](patterns/mo.hexpat) | GNU Machine Object (MO) files containing translations for gettext |
 | mp4 | `video/mp4` | [`patterns/mp4.hexpat`](patterns/mp4.hexpat) | MPEG-4 Part 14 digital multimedia container format |
 | msgpack | `application/x-msgpack` | [`patterns/msgpack.hexpat`](patterns/msgpack.hexpat) | MessagePack binary serialization format |
 | MSSCMP | | [`patterns/msscmp.hexpat`](patterns/msscmp.hexpat) | Miles Sound System Compressed Archive |

patterns/mo.hexpat

@@ -0,0 +1,37 @@
+#pragma author dvob
+#pragma description GNU Machine Object (MO) files containing translations for gettext
+
+// https://www.gnu.org/software/gettext/manual/html_node/MO-Files.html
+
+import std.core;
+import std.io;
+
+struct strPtr {
+    u32 length;
+    u32 offset;
+    char string[length] @ offset;
+};
+
+struct file {
+    be u32 magic;
+    if ( magic == 0x950412de )
+        std::core::set_endian(std::mem::Endian::Big);
+    else if ( magic == 0xde120495)
+        std::core::set_endian(std::mem::Endian::Little);
+    else
+        std::error("Invalid MO Magic!");
+
+    u16 majorVersion;
+    u16 minorVersion;
+    u32 count;
+    u32 msgIdOffset;
+    u32 msgStrOffset;
+    u32 hashSize;
+    u32 hashOffset;
+
+    u32 hashTable[hashSize] @ hashOffset;
+    strPtr msgIDTable[count] @ msgIdOffset;
+    strPtr msgStrTable[count] @ msgStrOffset;
+};
+
+file moFile @ 0x0;