From df1ef68cd8e8582724ce1192bfc202e0b9aeaf0c Mon Sep 17 00:00:00 2001 From: Karen Arutyunov Date: Tue, 28 Sep 2021 19:24:31 +0300 Subject: Get rid of C++ modules related code and rename *.mxx files to *.hxx --- libbutl/path-map.hxx | 128 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 128 insertions(+) create mode 100644 libbutl/path-map.hxx (limited to 'libbutl/path-map.hxx') diff --git a/libbutl/path-map.hxx b/libbutl/path-map.hxx new file mode 100644 index 0000000..a7b3870 --- /dev/null +++ b/libbutl/path-map.hxx @@ -0,0 +1,128 @@ +// file : libbutl/path-map.hxx -*- C++ -*- +// license : MIT; see accompanying LICENSE file + +#pragma once + +#include // min() + +#include +#include + +#include + +namespace butl +{ + // prefix_map for filesystem paths + // + // Important: the paths should be normalized but can use different directory + // separators and different case on case-insensitive platforms. + // + // Note that the path's representation of POSIX root ('/') is inconsistent + // in that we have a trailing delimiter at the end of the path (its "proper" + // representation would have been an empty string but that would have + // clashed with empty paths). To work around this snag, this implementation, + // during key comparison, detects '/' and treats it as empty. Note that the + // map will still store the key as you have first inserted it. So if you + // want a particular representation (i.e., empty or '/'), pre- populate the + // map with it. + // + template + struct compare_prefix> + { + typedef basic_path key_type; + + typedef C delimiter_type; + typedef typename key_type::string_type string_type; + typedef typename key_type::size_type size_type; + typedef typename key_type::traits_type traits_type; + + explicit + compare_prefix (delimiter_type) {} + + bool + operator() (const key_type& x, const key_type& y) const + { + const string_type& xs (x.string ()); + const string_type& ys (y.string ()); + + return compare (xs.c_str (), + root (xs) ? 0 : xs.size (), + ys.c_str (), + root (ys) ? 0 : ys.size ()) < 0; + } + + bool + prefix (const key_type& p, const key_type& k) const + { + const string_type& ps (p.string ()); + const string_type& ks (k.string ()); + + return prefix (root (ps) ? string_type () : ps, + root (ks) ? string_type () : ks); + } + + bool + prefix (key_type& k) const + { + if (k.empty ()) + return false; + + k.make_directory (); + return true; + } + + protected: + bool + prefix (const string_type& p, const string_type& k) const + { + // The same code as in prefix_map but using our compare(). + // + size_type pn (p.size ()), kn (k.size ()); + return pn == 0 || // Empty key is always a prefix. + (pn <= kn && + compare (p.c_str (), pn, k.c_str (), pn == kn ? pn : pn + 1) == 0); + } + + int + compare (const C* x, size_type xn, + const C* y, size_type yn) const + { + size_type n (std::min (xn, yn)); + int r (traits_type::compare (x, n, y, n)); + + if (r == 0) + { + // Pretend there is a delimiter characters at the end of the + // shorter string. + // + char xc (xn > n ? x[n] : (xn++, traits_type::directory_separator)); + char yc (yn > n ? y[n] : (yn++, traits_type::directory_separator)); + r = traits_type::compare (&xc, 1, &yc, 1); + + // If we are still equal, then compare the lengths. + // + if (r == 0) + r = (xn == yn ? 0 : (xn < yn ? -1 : 1)); + } + + return r; + } + + static bool + root (const string_type& p) + { + return p.size () == 1 && key_type::traits_type::is_separator (p[0]); + } + }; + + // Note that the delimiter character is not used (is_delimiter() from + // path_traits is used instead). + // + template + using path_map = + prefix_map; + + template + using dir_path_map = + prefix_map; +} -- cgit v1.1