patterns: Added Tar Pattern (#64)

* patterns: add tar support

* readme: add tar entry

* patterns: update tar file

Co-authored-by: favaioos <120850826+favaioos@users.noreply.github.com>

README.md

@@ -47,6 +47,7 @@ Hex patterns, include patterns and magic files for the use with the ImHex Hex Ed
 | msgpack | `application/x-msgpack` | [`patterns/msgpack.hexpat`](patterns/msgpack.hexpat) | MessagePack binary serialization format | 
 | MiniDump | `application/x-dmp` | [`patterns/minidump.hexpat`](patterns/minidump.hexpat) | Windows MiniDump files | 
 | ID3 | `audio/mpeg` | [`patterns/id3tag.hexpat`](patterns/id3tag.hexpat) | ID3 tags in MP3 files |
+| TAR | `application/x-tar` | [`patterns/tar.hexpat`](patterns/tar.hexpat) | Tar file format |
 
 ### Scripts
 

patterns/tar.hexpat

@@ -0,0 +1,88 @@
+#pragma MIME application/tar
+#pragma MIME application/x-tar
+
+#pragma endian little
+
+#include <std/string.pat>
+#include <std/time.pat>
+#include <std/mem.pat>
+#include <std/sys.pat>
+
+
+#define HEADER "ustar "
+#define NULL "\x00"
+
+fn octal_to_decimal(str value) {
+    return std::string::parse_int(value, 8);
+};
+
+fn get_time(str time) {
+    std::time::EpochTime epochtime = octal_to_decimal(time);
+    std::time::Time localtime = std::time::to_local(epochtime);
+    return std::time::format(localtime, "%c");
+};
+
+enum typeflagenum : char {
+    regular = '0',
+    also_regular = '\x00',
+    link_to_another_file_already_archived = '1',
+    symbolic_link = '2',
+    character_special_device = '3',
+    block_special_device = '4',
+    directory = '5',
+    fifo_special_file = '6',
+    reserved = '7'
+};
+
+struct posix_header {
+  char name[100] [[name("file name")]];
+  char mode[8] [[name("file mode")]];
+  char uid[8] [[name("user id of the file")]];
+  char gid[8] [[name("group if of the file")]];
+  char size[12] [[name("size of the file in octal")]];
+  char mtime[12] [[name("modified time of file in epoch time")]];
+  char chksum[8] [[name("checksum")]];
+  typeflagenum typeflag [[name("type of file")]];
+  char linkname[100] [[name("name of link")]];
+  char magic[6] [[name("magic bytes that identifies the 'file version'")]];
+  char version[2] [[name("version (also used with magic bytes)")]];
+  char uname[32] [[name("username of the owner of the file")]];
+  char gname[32] [[name("group name of the owner of the file")]];
+  char devmajor[8] [[name("major device numbers")]];
+  char devminor[8] [[name("minor device numbers")]];
+  char prefix[155] [[name("filename prefix")]];
+  char reserved[12] [[name("reserved")]];
+};
+
+
+struct tar {
+    posix_header header_raw;
+    char file[octal_to_decimal(header_raw.size)];
+    
+    std::print("-" * 50);
+    std::print("File Name: {}", header_raw.name);
+    std::print("File Permissions: {}" , header_raw.mode);
+    std::print("UID: {}", header_raw.uid);
+    std::print("GUID: {}", header_raw.gid);
+    std::print("Size: {} bytes", octal_to_decimal(header_raw.size));
+    std::print("Modified Time: {}", get_time(header_raw.mtime));
+    std::print("Checksum: {}", header_raw.chksum);
+    std::print("Type of File: {}", header_raw.typeflag);
+    std::print("Magic Bytes: {}", header_raw.magic);
+    std::print("Version: {}", header_raw.version);
+    std::print("uname: {}", header_raw.uname);
+    std::print("gname: {}", header_raw.gname);
+    std::print("devmajor: {}", header_raw.devmajor);
+    std::print("devminor: {}", header_raw.devminor);
+    std::print("prefix: {}", header_raw.prefix);
+    
+    char empty[while (std::mem::read_string($, 1) == NULL && !std::mem::eof())];
+    if (std::mem::eof()) {
+        break;
+    }
+};
+
+char magic[6] @ 0x00000101 [[hidden]];
+std::assert(magic == HEADER, "Magic bytes are not correct! Perhaps wrong file?");
+
+tar tar[while(!std::mem::eof())] @ 0x000;