Class: LibmagicRb

Inherits:
Object
  • Object
show all
Defined in:
lib/libmagic_rb/version.rb,
ext/libmagic/magic.c

Defined Under Namespace

Classes: FileClosedError, FileNotFound, FileUnreadable, InvalidDBError, IsDirError

Constant Summary collapse

VERSION = 
"0.2.0"
MAGIC_VERSION =

:MAGIC_VERSION returns the magic version of the library. For older libmagic version, this can be undefined, so this method will return “0” instead.

rb_str_new_cstr("0")

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(args) ⇒ Object

Intializes a magic cookie that can be used multiple times. The benefit of this is to assgign various cookies and change flags of each cookie.

For example:

> cookie = LibmagicRb.new(file: ‘/tmp’) # => #<LibmagicRb:0x000055810139f738 @closed=false, @db=nil, @file=“/tmp”, @mode=1106>

> cookie.check # => “inode/directory; charset=binary”

> cookie.setflags(LibmagicRb::MAGIC_RAW) # => 256

> cookie.check # => “sticky, directory”

> cookie2 = LibmagicRb.new(file: ‘/usr/share/dict/words’) # => #<LibmagicRb:0x000055810190a060 @closed=false, @db=nil, @file=“/usr/share/dict/words”, @mode=1106>

> cookie2.check # => “text/plain; charset=utf-8”

> cookie.close # => #<LibmagicRb:0x000055810139f738 @closed=true, @db=nil, @file=“/tmp”, @mode=256>

> cookie.closed? # => true

> cookie2.closed? # => false

Here in this example, we can’t use cookie, but cookie2 is a different magic_t wrapper, so we can continue using that. Flags/modes applied to cookie, will not affect cookie2 as well. Think of them as totally different containers. Of course, you must close cookies when you don’t need them. Otherwise it can use memories unless GC is triggered.



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# File 'ext/libmagic/magic.c', line 170

VALUE rb_libmagicRb_initialize(VALUE self, VALUE args) {
	// Database Path
	if(!RB_TYPE_P(args, T_HASH)) {
		rb_raise(rb_eArgError, "Expected hash as argument.");
	}

	VALUE argDBPath = rb_hash_aref(args, ID2SYM(rb_intern("db")));

	if (RB_TYPE_P(argDBPath, T_NIL)) {
		rb_ivar_set(self, rb_intern("@db"), Qnil);
	} else if (!RB_TYPE_P(argDBPath, T_STRING)) {
		rb_raise(rb_eArgError, "Database name must be an instance of String.");
	} else {
		rb_ivar_set(self, rb_intern("@db"), argDBPath);
	}

	// File path
	VALUE argFilePath = rb_hash_aref(args, ID2SYM(rb_intern("file")));
	if (RB_TYPE_P(argFilePath, T_NIL)) {
		rb_raise(rb_eArgError, "Expected `file:\" key as a string, got nil instead");
	} else if (!RB_TYPE_P(argFilePath, T_STRING)) {
		rb_raise(rb_eArgError, "Filename must be an instance of String.");
	}
	rb_ivar_set(self, rb_intern("@file"), argFilePath);

	// Modes
	VALUE argModes = rb_hash_aref(args, ID2SYM(rb_intern("mode")));
	unsigned int modes;
	if(RB_TYPE_P(argModes, T_NIL)) {
		modes = MAGIC_MIME | MAGIC_CHECK | MAGIC_SYMLINK;
	} else if (!RB_TYPE_P(argModes, T_FIXNUM)) {
		rb_raise(rb_eArgError, "Modes must be an instance of Integer. Check LibmagicRb.constants() or LibmagicRb.lsmodes().");
	} else {
		modes = FIX2UINT(argModes);
	}
	rb_ivar_set(self, rb_intern("@mode"), UINT2NUM(modes));

	rb_ivar_set(self, rb_intern("@closed"), Qfalse);

	RB_UNWRAP(cookie);
	magic_setflags(*cookie, modes);

	return self;
}

Instance Attribute Details

#closed ⇒ Object (readonly) Also known as: closed?

Attributes

#db ⇒ Object

#file ⇒ Object

#mode ⇒ Object (readonly)

Class Method Details

.check(args) ⇒ Object

Directly check a file with LibmagicRb, without creating any sort of cookies:

LibmagicRb.check(file: ‘/tmp/’, db: ‘/usr/share/file/misc/magic.mgc’, mode: LibmagicRb::MAGIC_CHECK) # => “sticky, directory”

file

The key ‘file:` is the filename to check. Should be a string

db

The key ‘db:` can be left as nil. Or you can give it the path of the current magic database.

mode

The key ‘mode` can be any of the LibmagicRb.lsmodes().

To combine modes you can use ‘|`. For example: `mode: LibmagicRb::MAGIC_CHECK | LibmagicRb::MAGIC_SYMLINK | Libmagic_MAGIC_MIME` If `mode` key is nil, it will default to `MAGIC_MIME | MAGIC_CHECK | MAGIC_SYMLINK`



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# File 'ext/libmagic/magic.c', line 68

static VALUE _check_(VALUE obj, VALUE args) {
	if(!RB_TYPE_P(args, T_HASH)) {
		rb_raise(rb_eArgError, "Expected hash as argument.");
	}

	// Database Path
	VALUE argDBPath = rb_hash_aref(args, ID2SYM(rb_intern("db")));

	char *databasePath = NULL;
	if (!NIL_P(argDBPath)) {
		if (!RB_TYPE_P(argDBPath, T_STRING)) {
			rb_raise(rb_eArgError, "Database name must be an instance of String.");
		}

		databasePath = StringValuePtr(argDBPath);
	}

	// File path
	VALUE argFilePath = rb_hash_aref(args, ID2SYM(rb_intern("file")));
	if (RB_TYPE_P(argFilePath, T_NIL)) {
		rb_raise(rb_eArgError, "Expected `file:\" key as a string, got nil instead");
	} else if (!RB_TYPE_P(argFilePath, T_STRING)) {
		rb_raise(rb_eArgError, "Filename must be an instance of String.");
	}
	char *checkPath = StringValuePtr(argFilePath);

	// Modes
	VALUE argModes = rb_hash_aref(args, ID2SYM(rb_intern("mode")));
	unsigned int modes;
	if(RB_TYPE_P(argModes, T_NIL)) {
		modes = MAGIC_MIME | MAGIC_CHECK | MAGIC_SYMLINK;
	} else if (!RB_TYPE_P(argModes, T_FIXNUM)) {
		rb_raise(rb_eArgError, "Modes must be an instance of Integer. Check LibmagicRb.constants() or LibmagicRb.lsmodes().");
	} else {
		modes = FIX2UINT(argModes);
	}

	// Checks
	struct magic_set *magic = magic_open(modes);

	if (!magic) {
		rb_raise(rb_eRuntimeError, "Failed to initialize magic cookie.");
	}

	// Check if the database is a valid file or not
	// Raises ruby error which will return.
	fileReadable(checkPath);

	if(databasePath) {
		magic_validate_db(magic, databasePath);
	}

	if (magic_load(magic, databasePath) == -1) {
		magic_close(magic);
		rb_raise(rb_eInvalidDBError, "Failed to load magic database: %s", magic_error(magic));
	}

	const char *mt = magic_file(magic, checkPath);

	VALUE retVal = mt ? rb_str_new_cstr(mt) : Qnil;
	magic_close(magic);

	return retVal;
}

.lsmodes ⇒ Object

.lsparams ⇒ Object

Instance Method Details

#check ⇒ Object

Check for file mimetype

#close ⇒ Object

Close database

#getparam ⇒ Object

Get and set params

#load ⇒ Object

Load database

#magic_buffer ⇒ Object

Miscellaneous

#magic_list ⇒ Object

#mode= ⇒ Object (readonly)

#setflags ⇒ Object

Set modes dynamically

#setparam ⇒ Object