libcruft-util/uri.cpp

#include "./uri.hpp"

#include "./debug/panic.hpp"

using cruft::uri;


///////////////////////////////////////////////////////////////////////////////
cruft::uri::uri (const char *str):
    uri (std::string (str))
{ ; }


//-----------------------------------------------------------------------------
uri::uri (cruft::view<const char *> _value):
    uri (std::string (_value.begin (), _value.end ()))
{ ; }


//-----------------------------------------------------------------------------
uri::uri (const std::string &_value):
    uri (std::string (_value))
{ ; }


///////////////////////////////////////////////////////////////////////////////
static uint8_t
hex_to_uint (char c)
{
    if (c >= '0' && c <= '9')
        return c - '0';

    if (c >= 'A' && c <= 'F')
        return c - 'A' + 10;

    if (c >= 'a' && c <= 'f')
        return c - 'a' + 10;

    unreachable ();
}


//-----------------------------------------------------------------------------
std::string
cruft::uri::percent_decode (view<const char*> s)
{
    if (s.size () == 0)
        return std::string ();

    // Early check for late percent-encoding so we can simplify the decode loop
    {
        auto tail = std::find (s.size () < 3 ? s.begin ()
                                             : s.end () - 2,
                               s.end (),
                               '%');
        if (tail != s.end ())
            throw parse_error ("triple overlaps end");
    }

    // Allocate and size a potentially overlong output string. This allows us
    // to copy directly into its buffer. We'll shorten it at the end.
    std::string out;
    out.resize (s.size ());

    // Find the percent, copy until that, decode, advance, repeat.
    auto out_cursor = out.begin ();

    for (auto i = s.begin (); i < s.end (); ++i) {
        auto cursor = std::find (i, s.end (), '%');

        if (cursor == s.end ()) {
            out_cursor = std::copy (i, s.end (), out_cursor);
            break;
        }

        out_cursor = std::copy (i, cursor, out_cursor);
        *out_cursor = hex_to_uint (cursor[1]) << 4 | hex_to_uint(cursor[2]);

        i += 3;
    }

    out.resize (out.end () - out_cursor);
    return out;
}



//-----------------------------------------------------------------------------
std::ostream&
cruft::operator<< (std::ostream &os, cruft::uri::component c)
{
    switch (c) {
        case cruft::uri::SCHEME:         return os << "SCHEME";
        case cruft::uri::HIERARCHICAL:   return os << "HIERARCHICAL";
        case cruft::uri::AUTHORITY:      return os << "AUTHORITY";
        case cruft::uri::USER:           return os << "USER";
        case cruft::uri::HOST:           return os << "HOST";
        case cruft::uri::PORT:           return os << "PORT";
        case cruft::uri::PATH:           return os << "PATH";
        case cruft::uri::QUERY:          return os << "QUERY";
        case cruft::uri::FRAGMENT:       return os << "FRAGMENT";

        case cruft::uri::NUM_COMPONENTS:
            unreachable ();
    }

    unreachable ();
}


//-----------------------------------------------------------------------------
std::ostream&
cruft::operator<< (std::ostream &os, cruft::uri const &val)
{
    return os << val.value ();
}