Class: Magikku

Inherits:
Object
  • Object
show all
Defined in:
ext/magikku_native/magikku_native.c

Defined Under Namespace

Modules: Flags Classes: ClosedError, CompileError, DbLoadError, FlagError, InitFatal, MagikkuError

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.new(params = {}) ⇒ Object

Instantiates a new Magikku cookie which we can use to load magic databases, compile new databases, and identify files and string buffers.

Parameters:

  • Hash —

    params A hash of optional parameters to pass to the initializer.

Raises:

  • Magikku::DbLoadError An error is raised if the database cannot be loaded.

  • Magikku::InitFatal An error is raised if an unknown error is encountered initializing the cookie with libmagic.

See Also:



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# File 'ext/magikku_native/magikku_native.c', line 68

VALUE 
rb_magic_initialize(int argc, VALUE *argv, VALUE klass) {
  VALUE params = Qnil;
  VALUE flags_val, db_val;
  magic_t cookie; 
  int flags = 0;
  char *magicf = NULL;
  const char *error=NULL;

  rb_scan_args(argc, argv, "01", &params);

  if (params != Qnil) {
    Check_Type(params, T_HASH);

    flags_val=rb_hash_aref(params, ID2SYM(rb_intern("flags")));
    if (flags_val != Qnil) {
      Check_Type(flags_val, T_FIXNUM);
      flags = NUM2INT(flags_val);
    }

    db_val=rb_hash_aref(params, ID2SYM(rb_intern("db")));
    if (db_val != Qnil) {
      Check_Type(db_val, T_STRING);
      magicf = RSTRING_PTR(db_val);
    }
  }

  if ((cookie=magic_open(flags))==NULL)
    rb_raise(e_InitFatal, "magic_open(%i) returned a null pointer", flags);

  if (magic_load(cookie, magicf) != 0) {
    error = magic_error(cookie);
    magic_close(cookie);
    rb_raise(e_DbLoadError, "Error loading db \"%s\": %s", magicf, error);
  }

  return Data_Wrap_Struct(klass, NULL, NULL, cookie);
}

.path ⇒ Object

Returns String Returns the default magic database path.

Returns:

  • String Returns the default magic database path.



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# File 'ext/magikku_native/magikku_native.c', line 39

VALUE 
rb_magic_s_path(VALUE klass) {
  return rb_str_new2(magic_getpath(NULL, 0));
}

Instance Method Details

#check_syntax("some_magic_db") ⇒ Object

Can be used to check the validity of magic files before compiling them. This is basically a dry-run that can be used before compiling magicfile databases.

Note: Errors and warnings may be displayed on stderr.

Parameters:

  • String,nil —

    filename A colon seperated list of filenames or a single file. nil checks the default database.

Returns:

  • true,false Indicates whether the check was successful.



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# File 'ext/magikku_native/magikku_native.c', line 277

VALUE rb_magic_check_syntax(VALUE self, VALUE rb_magicf) {
  magic_t cookie = _check_closed(self);
  char * magicf = NULL;

  if (!cookie) rb_raise(e_ClosedError, CLOSED_ERR_MSG);
  if (rb_magicf != Qnil) {
    Check_Type(rb_magicf, T_STRING);
    magicf = RSTRING_PTR(rb_magicf);
  }

  if (magic_check(cookie, magicf) == 0) return Qtrue;
  else return Qfalse;
}

#close ⇒ nil

Close the libmagic data scanner handle when you are finished with it

Note that magic handles are never closed automatically, even when garbage collection occurs.

Returns:

  • (nil) 


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# File 'ext/magikku_native/magikku_native.c', line 150

VALUE 
rb_magic_close(VALUE self) {
  magic_t cookie = _check_closed(self);

  if(cookie) magic_close(cookie);
  rb_iv_set(self, "@closed", Qtrue);

  return Qnil;
}

#closed? ⇒ Boolean

Indicates whether the magic cookie has been closed

Returns:

  • (Boolean) —

    true,false



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# File 'ext/magikku_native/magikku_native.c', line 166

VALUE 
rb_magic_is_closed(VALUE self) {
  VALUE ret = rb_iv_get(self, "@closed");
  if (ret == Qnil) ret = Qfalse;
  return ret;
}

#compile(filename = nil) ⇒ Object

Can be used to compile magic files. This does not load files, however. You must use dbload for that.

Note: Errors and warnings may be displayed on stderr.

Parameters:

  • String,nil —

    filename A colon seperated list of filenames or a single filename. The compiled files created are generated in the current directory using the basename(1) of each file argument with “.mgc” appended to it. Directory names can be compiled, in which case the contents of the directory will be compiled together as a single .mgc file. nil compiles the default database.

Returns:

  • true if everything went well.

Raises:

  • CompileError if an error occurred.



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# File 'ext/magikku_native/magikku_native.c', line 249

VALUE rb_magic_compile(VALUE self, VALUE magicf) {
  char *_magicf;
  magic_t cookie = _check_closed(self);

  if (!cookie)          rb_raise(e_ClosedError, CLOSED_ERR_MSG);
  if (magicf != Qnil)   Check_Type(magicf, T_STRING);

  _magicf = RSTRING_PTR(magicf);

  if (magic_compile(cookie, _magicf) == 0) return Qtrue;
  else rb_raise(e_CompileError, 
        "Error compiling \"%s\": %s", _magicf, magic_error(cookie));
}

#dbload(magicfiles) ⇒ true

Used to load one or more magic databases.

Returns:

  • (true)

Parameters:

  • String —

    magicfiles One or more filenames seperated by colons. If nil, the default database is loaded. If uncompiled magic files are specified, they are compiled on the fly but they do not generate new .mgc files as with the compile method. Multiple files be specified by seperating them with colons.

Raises:

  • DbLoadError if an error occurred loading the database(s)

  • Magikku::CloseError Raises an error if the Magikku object has been closed.



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# File 'ext/magikku_native/magikku_native.c', line 124

VALUE 
rb_magic_dbload(VALUE self, VALUE magicf_val) {
  magic_t cookie = _check_closed(self);
  char *magicf = NULL;

  if(!cookie)             rb_raise(e_ClosedError, CLOSED_ERR_MSG);
  if(magicf_val != Qnil){
    Check_Type(magicf_val, T_STRING);
    magicf = RSTRING_PTR(magicf_val);
  }

  Data_Get_Struct(self, void, cookie);

  if (magic_load(cookie, magicf) != 0)
    rb_raise(e_DbLoadError, "Error loading db \"%s\": %s", magicf, magic_error(cookie));

  return Qtrue;
}

#file(filename) ⇒ String

Identifies file contents using the magicfile database.

Returns:

  • (String)

Parameters:

  • String —

    filename The path to the file to analyze

Returns:

  • String A textual description of the contents of the file

Raises:

  • Magikku::CloseError Raises an error if the Magikku object has been closed.



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# File 'ext/magikku_native/magikku_native.c', line 186

VALUE 
rb_magic_file(VALUE self, VALUE filename) {
  magic_t cookie = _check_closed(self);
  if (cookie) {
    char * fname;
    struct stat st;

    Check_Type(filename, T_STRING);
    fname = RSTRING_PTR(filename);

    if(stat(fname, &st) < 0) 
      rb_sys_fail(fname);

    return rb_str_new2(magic_file(cookie, fname));

  } else {
    rb_raise(e_ClosedError, CLOSED_ERR_MSG);
  }
      
}

#flags=(flags) ⇒ Object

Sets libmagic flags on the object. See Magikku::Flags

Raises:

  • Magikku::CloseError Raises an error if the Magikku object has been closed.



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# File 'ext/magikku_native/magikku_native.c', line 298

VALUE rb_magic_set_flags(VALUE self, VALUE flags) {
  magic_t cookie = _check_closed(self);

  Check_Type(flags, T_FIXNUM);
  
  if(magic_setflags(cookie, NUM2INT(flags)) < 0)
    rb_raise(e_FlagError, magic_error(cookie));

  return flags;
}

#string(buf) ⇒ String

Identifies string contents using the magicfile database.

Returns:

  • (String)

Parameters:

  • String —

    buf The string to analyze.

Returns:

  • String A textual description of the contents of the string

Raises:

  • Magikku::CloseError Raises an error if the Magikku object has been closed.



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# File 'ext/magikku_native/magikku_native.c', line 220

VALUE rb_magic_string(VALUE self, VALUE string) {
  const char *ret;
  magic_t cookie = _check_closed(self);
  if (!cookie)          rb_raise(e_ClosedError, CLOSED_ERR_MSG);
  Check_Type(string, T_STRING);

  ret=magic_buffer(cookie, RSTRING_PTR(string), RSTRING_LEN(string));
  return rb_str_new2(ret);
}