Commit f0e6c292 authored by JINMEI Tatuya's avatar JINMEI Tatuya
Browse files

merged branches/trac49 (for trac #49) (and the usual mergeinfo...)

make/test okay.


git-svn-id: svn://bind10.isc.org/svn/bind10/trunk@1903 e5f2f494-b856-4b98-b285-d166d9295462
parent 8a417d07
......@@ -666,7 +666,7 @@ Name::reverse() const {
}
Name
Name::split(unsigned int first, unsigned int n) const {
Name::split(const unsigned int first, const unsigned int n) const {
if (n == 0 || n > labelcount_ || first > labelcount_ - n) {
isc_throw(OutOfRange, "Name::split: invalid split range");
}
......@@ -702,6 +702,16 @@ Name::split(unsigned int first, unsigned int n) const {
return (retname);
}
Name
Name::split(const unsigned level) const {
if (level >= getLabelCount()) {
isc_throw(OutOfRange, "invalid level for name split (" << level
<< ") for name " << *this);
}
return (split(level, getLabelCount() - level));
}
Name&
Name::downcase() {
unsigned int nlen = length_;
......
......@@ -84,7 +84,7 @@ public:
///
/// \brief A standard DNS module exception that is thrown if the name parser
/// finds the input (string or wire-format data) is incomplete.
/// finds the input (string or wire-format %data) is incomplete.
///
/// An attempt of constructing a name from an empty string will trigger this
/// exception.
......@@ -168,13 +168,13 @@ private:
///
/// The \c Name class encapsulates DNS names.
///
/// It provides interfaces to construct a name from string or wire-format data,
/// transform a name into a string or wire-format data, compare two names, get
/// It provides interfaces to construct a name from string or wire-format %data,
/// transform a name into a string or wire-format %data, compare two names, get
/// access to various properties of a name, etc.
///
/// Notes to developers: Internally, a name object maintains the name data
/// Notes to developers: Internally, a name object maintains the name %data
/// in wire format as an instance of \c std::string. Since many string
/// implementations adopt copy-on-write data sharing, we expect this approach
/// implementations adopt copy-on-write %data sharing, we expect this approach
/// will make copying a name less expensive in typical cases. If this is
/// found to be a significant performance bottleneck later, we may reconsider
/// the internal representation or perhaps the API.
......@@ -187,9 +187,9 @@ private:
/// included. In the BIND9 DNS library from which this implementation is
/// derived, the offsets are optional, probably due to performance
/// considerations (in fact, offsets can always be calculated from the name
/// data, and in that sense are redundant). In our implementation, however,
/// %data, and in that sense are redundant). In our implementation, however,
/// we always build and maintain the offsets. We believe we need more low
/// level, specialized data structure and interface where we really need to
/// level, specialized %data structure and interface where we really need to
/// pursue performance, and would rather keep this generic API and
/// implementation simpler.
///
......@@ -233,21 +233,21 @@ public:
/// \param namestr A string representation of the name to be constructed.
/// \param downcase Whether to convert upper case alphabets to lower case.
explicit Name(const std::string& namestr, bool downcase = false);
/// Constructor from wire-format data.
/// Constructor from wire-format %data.
///
/// The \c buffer parameter normally stores a complete DNS message
/// containing the name to be constructed. The current read position of
/// the buffer points to the head of the name.
///
/// The input data may or may not be compressed; if it's compressed, this
/// The input %data may or may not be compressed; if it's compressed, this
/// method will automatically decompress it.
///
/// If the given data does not represent a valid DNS name, an exception
/// If the given %data does not represent a valid DNS name, an exception
/// of class \c DNSMessageFORMERR will be thrown.
/// In addition, if resource allocation for the new name fails, a
/// corresponding standard exception will be thrown.
///
/// \param buffer A buffer storing the wire format data.
/// \param buffer A buffer storing the wire format %data.
/// \param downcase Whether to convert upper case alphabets to lower case.
explicit Name(InputBuffer& buffer, bool downcase = false);
///
......@@ -260,35 +260,35 @@ public:
/// \name Getter Methods
///
//@{
/// \brief Provides one-byte name data in wire format at the specified
/// \brief Provides one-byte name %data in wire format at the specified
/// position.
///
/// This method returns the unsigned 8-bit value of wire-format \c Name
/// data at the given position from the head.
/// %data at the given position from the head.
///
/// For example, if \c n is a \c Name object for "example.com",
/// \c n.at(3) would return \c 'a', and \c n.at(7) would return \c 'e'.
/// Note that \c n.at(0) would be 7 (decimal), the label length of
/// "example", instead of \c 'e', because it returns a data portion
/// "example", instead of \c 'e', because it returns a %data portion
/// in wire-format. Likewise, \c n.at(8) would return 3 (decimal)
/// instead of <code>'.'</code>
///
/// This method would be useful for an application to examine the
/// wire-format name data without dumping the data into a buffer,
/// which would involve data copies and would be less efficient.
/// wire-format name %data without dumping the %data into a buffer,
/// which would involve %data copies and would be less efficient.
/// One common usage of this method would be something like this:
/// \code for (size_t i = 0; i < name.getLength(); ++i) {
/// uint8_t c = name.at(i);
/// // do something with c
/// } \endcode
///
/// Parameter \c pos must be in the valid range of the name data, that is,
/// Parameter \c pos must be in the valid range of the name %data, that is,
/// must be less than \c Name.getLength(). Otherwise, an exception of
/// class \c OutOfRange will be thrown.
/// This method never throws an exception in other ways.
///
/// \param pos The position in the wire format name data to be returned.
/// \return An unsigned 8-bit integer corresponding to the name data
/// \param pos The position in the wire format name %data to be returned.
/// \return An unsigned 8-bit integer corresponding to the name %data
/// at the position of \c pos.
uint8_t at(size_t pos) const
{
......@@ -360,7 +360,7 @@ public:
/// <code>buffer.getCapacity() - buffer.getLength() >= Name::MAX_WIRE</code>
/// then this method should not throw an exception.
///
/// \param buffer An output buffer to store the wire data.
/// \param buffer An output buffer to store the wire %data.
void toWire(OutputBuffer& buffer) const;
//@}
......@@ -502,6 +502,72 @@ public:
/// labels including and following the <code>first</code> label.
Name split(unsigned int first, unsigned int n) const;
/// \brief Extract a specified super domain name of Name.
///
/// This function constructs a new \c Name object that is a super domain
/// of \c this name.
/// The new name is \c level labels upper than \c this name.
/// For example, when \c name is www.example.com,
/// <code>name.split(1)</code> will return a \c Name object for example.com.
/// \c level can be 0, in which case this method returns a copy of
/// \c this name.
/// The possible maximum value for \c level is
/// <code>this->getLabelCount()-1</code>, in which case this method
/// returns a root name.
///
/// One common expected usage of this method is to iterate over super
/// domains of a given name, label by label, as shown in the following
/// sample code:
/// \code // if name is www.example.com...
/// for (int i = 0; i < name.getLabelCount(); ++i) {
/// Name upper_name(name.split(i));
/// // upper_name'll be www.example.com., example.com., com., and then .
/// }
/// \endcode
///
/// \c level must be smaller than the number of labels of \c this name;
/// otherwise an exception of class \c OutOfRange will be thrown.
/// In addition, if resource allocation for the new name fails, a
/// corresponding standard exception will be thrown.
///
/// Note to developers: probably as easily imagined, this method is a
/// simple wrapper to one usage of the other
/// <code>split(unsigned int, unsigned int) const</code> method and is
/// redundant in some sense.
/// We provide the "redundant" method for convenience, however, because
/// the expected usage shown above seems to be common, and the parameters
/// to the other \c split(unsigned int, unsigned int) const to implement
/// it may not be very intuitive.
///
/// We are also aware that it is generally discouraged to add a public
/// member function that could be implemented using other member functions.
/// We considered making it a non member function, but we could not come
/// up with an intuitive function name to represent the specific service.
/// Some other BIND 10 developers argued, probably partly because of the
/// counter intuitive function name, a different signature of \c split
/// would be better to improve code readability.
/// While that may be a matter of personal preference, we accepted the
/// argument. One major goal of public APIs like this is wider acceptance
/// from internal/external developers, so unless there is a clear advantage
/// it would be better to respect the preference of the API users.
///
/// Since this method doesn't have to be a member function in other way,
/// it is intentionally implemented only using public interfaces of the
/// \c Name class; it doesn't refer to private members of the class even if
/// it could.
/// This way we hope we can avoid damaging the class encapsulation,
/// which is a major drawback of public member functions.
/// As such if and when this "method" has to be extended, it should be
/// implemented without the privilege of being a member function unless
/// there is a very strong reason to do so. In particular a minor
/// performance advantage shouldn't justify that approach.
///
/// \param level The number of labels to be removed from \c this name to
/// create the super domain name.
/// (0 <= \c level < <code>this->getLabelCount()</code>)
/// \return A new \c Name object to be created.
Name split(unsigned int level) const;
/// \brief Reverse the labels of a name
///
/// This method reverses the labels of a name. For example, if
......
......@@ -500,6 +500,18 @@ TEST_F(NameTest, split) {
OutOfRange);
}
TEST_F(NameTest, split_for_suffix) {
EXPECT_PRED_FORMAT2(UnitTestUtil::matchName, example_name.split(1),
Name("example.com"));
EXPECT_PRED_FORMAT2(UnitTestUtil::matchName, example_name.split(0),
example_name);
EXPECT_PRED_FORMAT2(UnitTestUtil::matchName, example_name.split(3),
Name("."));
// Invalid case: the level must be less than the original label count.
EXPECT_THROW(example_name.split(4), OutOfRange);
}
TEST_F(NameTest, downcase) {
// usual case: all-upper case name to all-lower case
compareInWireFormat(example_name_upper.downcase(), example_name);
......
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