Module: Digest::Instance

Included in:
Class
Defined in:
digest.c,
lib/digest.rb

Overview

This module provides instance methods for a digest implementation object to calculate message digest values.

Instance Method Summary collapse

Instance Method Details

#update(string) ⇒ Object #<<(string) ⇒ Object

Updates the digest using a given string and returns self.

The update() method and the left-shift operator are overridden by each implementation subclass. (One should be an alias for the other)




# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.update(string) -> digest_obj
 *     digest_obj << string -> digest_obj
 *
 * Updates the digest using a given _string_ and returns self.
 *
 * The update() method and the left-shift operator are overridden by
 * each implementation subclass. (One should be an alias for the
 * other)
 */
static VALUE
rb_digest_instance_update(VALUE self, VALUE str)
{
    rb_raise(rb_eRuntimeError, "%s does not implement update()", RSTRING_PTR(rb_inspect(self)));
}

#==(another_digest_obj) ⇒ Boolean #==(string) ⇒ Boolean

If a string is given, checks whether it is equal to the hex-encoded hash value of the digest object. If another digest instance is given, checks whether they have the same hash value. Otherwise returns false.

Overloads:

  • #==(another_digest_obj) ⇒ Boolean

    Returns:

    • (Boolean)
  • #==(string) ⇒ Boolean

    Returns:

    • (Boolean) 



# File 'digest.c'

/*
 * call-seq:
 *     digest_obj == another_digest_obj -> boolean
 *     digest_obj == string -> boolean
 *
 * If a string is given, checks whether it is equal to the hex-encoded
 * hash value of the digest object.  If another digest instance is
 * given, checks whether they have the same hash value.  Otherwise
 * returns false.
 */
static VALUE
rb_digest_instance_equal(VALUE self, VALUE other)
{
    VALUE str1, str2;

    if (rb_obj_is_kind_of(other, rb_mDigest_Instance) == Qtrue) {
        str1 = rb_digest_instance_digest(0, 0, self);
        str2 = rb_digest_instance_digest(0, 0, other);
    } else {
        str1 = rb_digest_instance_to_s(self);
        str2 = other;
    }

    /* never blindly assume that subclass methods return strings */
    StringValue(str1);
    StringValue(str2);

    if (RSTRING_LEN(str1) == RSTRING_LEN(str2) &&
    rb_str_cmp(str1, str2) == 0) {
    return Qtrue;
    }
    return Qfalse;
}

#block_length ⇒ Integer

Returns the block length of the digest.

This method is overridden by each implementation subclass.

Returns:

  • (Integer) 



# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.block_length -> integer
 *
 * Returns the block length of the digest.
 *
 * This method is overridden by each implementation subclass.
 */
static VALUE
rb_digest_instance_block_length(VALUE self)
{
    rb_raise(rb_eRuntimeError, "%s does not implement block_length()", RSTRING_PTR(rb_inspect(self)));
}

#digest ⇒ String #digest(string) ⇒ String

If none is given, returns the resulting hash value of the digest, keeping the digest's state.

If a string is given, returns the hash value for the given string, resetting the digest to the initial state before and after the process.

Overloads:

  • #digest ⇒ String

    Returns:

    • (String)
  • #digest(string) ⇒ String

    Returns:

    • (String) 



# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.digest -> string
 *     digest_obj.digest(string) -> string
 *
 * If none is given, returns the resulting hash value of the digest,
 * keeping the digest's state.
 *
 * If a _string_ is given, returns the hash value for the given
 * _string_, resetting the digest to the initial state before and
 * after the process.
 */
static VALUE
rb_digest_instance_digest(int argc, VALUE *argv, VALUE self)
{
    VALUE str, value;

    if (rb_scan_args(argc, argv, "01", &str) > 0) {
        rb_funcall(self, id_reset, 0);
        rb_funcall(self, id_update, 1, str);
        value = rb_funcall(self, id_finish, 0);
        rb_funcall(self, id_reset, 0);
    } else {
        VALUE clone = rb_obj_clone(self);

        value = rb_funcall(clone, id_finish, 0);
        rb_funcall(clone, id_reset, 0);
    }

    return value;
}

#digest! ⇒ String

Returns the resulting hash value and resets the digest to the initial state.

Returns:

  • (String) 



# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.digest! -> string
 *
 * Returns the resulting hash value and resets the digest to the
 * initial state.
 */
static VALUE
rb_digest_instance_digest_bang(VALUE self)
{
    VALUE value = rb_funcall(self, id_finish, 0);
    rb_funcall(self, id_reset, 0);

    return value;
}

#digest_length ⇒ Integer

Returns the length of the hash value of the digest.

This method should be overridden by each implementation subclass. If not, digest_obj.digest().length() is returned.

Returns:

  • (Integer) 



# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.digest_length -> integer
 *
 * Returns the length of the hash value of the digest.
 *
 * This method should be overridden by each implementation subclass.
 * If not, digest_obj.digest().length() is returned.
 */
static VALUE
rb_digest_instance_digest_length(VALUE self)
{
    /* subclasses really should redefine this method */
    VALUE digest = rb_digest_instance_digest(0, 0, self);

    /* never blindly assume that #digest() returns a string */
    StringValue(digest);
    return INT2NUM(RSTRING_LEN(digest));
}

#file(name) ⇒ Object

updates the digest with the contents of a given file name and returns self.



36
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# File 'lib/digest.rb', line 36

def file(name)
  File.open(name, "rb") {|f|
    buf = ""
    while f.read(16384, buf)
      update buf
    end
  }
  self
end

#instance_eval { ... } ⇒ Object

Finishes the digest and returns the resulting hash value.

This method is overridden by each implementation subclass and often made private, because some of those subclasses may leave internal data uninitialized. Do not call this method from outside. Use #digest!() instead, which ensures that internal data be reset for security reasons.

Yields:




# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.instance_eval { finish } -> digest_obj
 *
 * Finishes the digest and returns the resulting hash value.
 *
 * This method is overridden by each implementation subclass and often
 * made private, because some of those subclasses may leave internal
 * data uninitialized.  Do not call this method from outside.  Use
 * #digest!() instead, which ensures that internal data be reset for
 * security reasons.
 */
static VALUE
rb_digest_instance_finish(VALUE self)
{
    rb_raise(rb_eRuntimeError, "%s does not implement finish()", RSTRING_PTR(rb_inspect(self)));
}

#hexdigest ⇒ String #hexdigest(string) ⇒ String

If none is given, returns the resulting hash value of the digest in a hex-encoded form, keeping the digest's state.

If a string is given, returns the hash value for the given string in a hex-encoded form, resetting the digest to the initial state before and after the process.

Overloads:

  • #hexdigest ⇒ String

    Returns:

    • (String)
  • #hexdigest(string) ⇒ String

    Returns:

    • (String) 



# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.hexdigest -> string
 *     digest_obj.hexdigest(string) -> string
 *
 * If none is given, returns the resulting hash value of the digest in
 * a hex-encoded form, keeping the digest's state.
 *
 * If a _string_ is given, returns the hash value for the given
 * _string_ in a hex-encoded form, resetting the digest to the initial
 * state before and after the process.
 */
static VALUE
rb_digest_instance_hexdigest(int argc, VALUE *argv, VALUE self)
{
    VALUE str, value;

    if (rb_scan_args(argc, argv, "01", &str) > 0) {
        rb_funcall(self, id_reset, 0);
        rb_funcall(self, id_update, 1, str);
        value = rb_funcall(self, id_finish, 0);
        rb_funcall(self, id_reset, 0);
    } else {
        VALUE clone = rb_obj_clone(self);

        value = rb_funcall(clone, id_finish, 0);
        rb_funcall(clone, id_reset, 0);
    }

    return hexencode_str_new(value);
}

#hexdigest! ⇒ String

Returns the resulting hash value and resets the digest to the initial state.

Returns:

  • (String) 



# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.hexdigest! -> string
 *
 * Returns the resulting hash value and resets the digest to the
 * initial state.
 */
static VALUE
rb_digest_instance_hexdigest_bang(VALUE self)
{
    VALUE value = rb_funcall(self, id_finish, 0);
    rb_funcall(self, id_reset, 0);

    return hexencode_str_new(value);
}

#inspect ⇒ String

Creates a printable version of the digest object.

Returns:

  • (String) 



# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.inspect -> string
 *
 * Creates a printable version of the digest object.
 */
static VALUE
rb_digest_instance_inspect(VALUE self)
{
    VALUE str;
    size_t digest_len = 32; /* about this size at least */
    char *cname;

    cname = rb_obj_classname(self);

    /* #<Digest::ClassName: xxxxx...xxxx> */
    str = rb_str_buf_new(2 + strlen(cname) + 2 + digest_len * 2 + 1);
    rb_str_buf_cat2(str, "#<");
    rb_str_buf_cat2(str, cname);
    rb_str_buf_cat2(str, ": ");
    rb_str_buf_append(str, rb_digest_instance_hexdigest(0, 0, self));
    rb_str_buf_cat2(str, ">");
    return str;
}

#length ⇒ Integer #size ⇒ Integer

Returns digest_obj.digest_length().

Overloads:

  • #length ⇒ Integer

    Returns:

    • (Integer)
  • #size ⇒ Integer

    Returns:

    • (Integer) 



# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.length -> integer
 *     digest_obj.size -> integer
 *
 * Returns digest_obj.digest_length().
 */
static VALUE
rb_digest_instance_length(VALUE self)
{
    return rb_funcall(self, id_digest_length, 0);
}

#new ⇒ Object

Returns a new, initialized copy of the digest object. Equivalent to digest_obj.clone().reset().




# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.new -> another_digest_obj
 *
 * Returns a new, initialized copy of the digest object.  Equivalent
 * to digest_obj.clone().reset().
 */
static VALUE
rb_digest_instance_new(VALUE self)
{
    VALUE clone = rb_obj_clone(self);
    rb_funcall(clone, id_reset, 0);
    return clone;
}

#reset ⇒ Object

Resets the digest to the initial state and returns self.

This method is overridden by each implementation subclass.




# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.reset -> digest_obj
 *
 * Resets the digest to the initial state and returns self.
 *
 * This method is overridden by each implementation subclass.
 */
static VALUE
rb_digest_instance_reset(VALUE self)
{
    rb_raise(rb_eRuntimeError, "%s does not implement reset()", RSTRING_PTR(rb_inspect(self)));
}

#length ⇒ Integer #size ⇒ Integer

Returns digest_obj.digest_length().

Overloads:

  • #length ⇒ Integer

    Returns:

    • (Integer)
  • #size ⇒ Integer

    Returns:

    • (Integer) 



# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.length -> integer
 *     digest_obj.size -> integer
 *
 * Returns digest_obj.digest_length().
 */
static VALUE
rb_digest_instance_length(VALUE self)
{
    return rb_funcall(self, id_digest_length, 0);
}

#to_s ⇒ String

Returns digest_obj.hexdigest().

Returns:

  • (String) 



# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.to_s -> string
 *
 * Returns digest_obj.hexdigest().
 */
static VALUE
rb_digest_instance_to_s(VALUE self)
{
    return rb_funcall(self, id_hexdigest, 0);
}

#update(string) ⇒ Object #<<(string) ⇒ Object

Updates the digest using a given string and returns self.

The update() method and the left-shift operator are overridden by each implementation subclass. (One should be an alias for the other)




# File 'digest.c'

/*
 * call-seq:
 *     digest_obj.update(string) -> digest_obj
 *     digest_obj << string -> digest_obj
 *
 * Updates the digest using a given _string_ and returns self.
 *
 * The update() method and the left-shift operator are overridden by
 * each implementation subclass. (One should be an alias for the
 * other)
 */
static VALUE
rb_digest_instance_update(VALUE self, VALUE str)
{
    rb_raise(rb_eRuntimeError, "%s does not implement update()", RSTRING_PTR(rb_inspect(self)));
}