aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--buildfile2
-rw-r--r--butl/prefix-map140
-rw-r--r--butl/prefix-map.txx39
-rw-r--r--tests/buildfile7
-rw-r--r--tests/prefix-map/buildfile7
-rwxr-xr-xtests/prefix-map/driverbin0 -> 199753 bytes
-rw-r--r--tests/prefix-map/driver.cxx153
7 files changed, 347 insertions, 1 deletions
diff --git a/buildfile b/buildfile
index 354f9da..3248471 100644
--- a/buildfile
+++ b/buildfile
@@ -2,6 +2,6 @@
# copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
# license : MIT; see accompanying LICENSE file
-d = butl/
+d = butl/ tests/
.: $d
include $d
diff --git a/butl/prefix-map b/butl/prefix-map
new file mode 100644
index 0000000..188d18f
--- /dev/null
+++ b/butl/prefix-map
@@ -0,0 +1,140 @@
+// file : butl/prefix-map -*- C++ -*-
+// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
+// license : MIT; see accompanying LICENSE file
+
+#ifndef BUTL_PREFIX_MAP
+#define BUTL_PREFIX_MAP
+
+#include <map>
+#include <string>
+#include <utility> // move
+#include <algorithm> // min
+
+namespace butl
+{
+ // A map of hierarchical "paths", e.g., 'foo.bar' or 'foo/bar' with
+ // the ability to retrieve a range of entries that have a specific
+ // prefix. The '.' and '/' above are the delimiter characters.
+ //
+ // Note that as a special rule, the default implementation of
+ // compare_prefix treats empty key as everyone's prefix even if
+ // the paths don't start with the delimiter (useful to represent
+ // a "root path").
+ //
+ // Implementation-wise, the idea is to pretend that each key ends
+ // with the delimiter. This way we automatically avoid matching
+ // 'foobar' as having a prefix 'foo'.
+ //
+ template <typename K>
+ struct compare_prefix;
+
+ template <typename C>
+ struct compare_prefix<std::basic_string<C>>
+ {
+ typedef std::basic_string<C> K;
+
+ typedef C delimiter_type;
+ typedef typename K::size_type size_type;
+ typedef typename K::traits_type traits_type;
+
+ explicit
+ compare_prefix (delimiter_type d): d_ (d) {}
+
+ bool
+ operator() (const K& x, const K& y) const
+ {
+ return compare (x.c_str (), x.size (), y.c_str (), y.size ()) < 0;
+ }
+
+ // Note: doesn't check for k.size () being at least p.size ().
+ //
+ bool
+ prefix (const K& p, const K& k) const
+ {
+ size_type pn (p.size ());
+ return pn == 0 || // Empty key is always a prefix.
+ compare (
+ p.c_str (), pn, k.c_str (), pn == k.size () ? pn : pn + 1) == 0;
+ }
+
+ protected:
+ 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, y, n));
+
+ if (r == 0)
+ {
+ // Pretend there is the delimiter characters at the end of the
+ // shorter string.
+ //
+ char xc (xn > n ? x[n] : (xn++, d_));
+ char yc (yn > n ? y[n] : (yn++, d_));
+ r = traits_type::compare (&xc, &yc, 1);
+
+ // If we are still equal, then compare the lengths.
+ //
+ if (r == 0)
+ r = (xn == yn ? 0 : (xn < yn ? -1 : 1));
+ }
+
+ return r;
+ }
+
+ private:
+ delimiter_type d_;
+ };
+
+ template <typename M>
+ struct prefix_map_common: M
+ {
+ typedef M map_type;
+ typedef typename map_type::key_type key_type;
+ typedef typename map_type::value_type value_type;
+ typedef typename map_type::key_compare compare_type;
+ typedef typename compare_type::delimiter_type delimiter_type;
+
+ typedef typename map_type::iterator iterator;
+ typedef typename map_type::const_iterator const_iterator;
+
+ explicit
+ prefix_map_common (delimiter_type d)
+ : map_type (compare_type (d)) {}
+
+ prefix_map_common (std::initializer_list<value_type> i, delimiter_type d)
+ : map_type (std::move (i), compare_type (d)) {}
+
+ std::pair<iterator, iterator>
+ find_prefix (const key_type&);
+
+ std::pair<const_iterator, const_iterator>
+ find_prefix (const key_type&) const;
+ };
+
+ template <typename M, typename prefix_map_common<M>::delimiter_type D>
+ struct prefix_map_impl: prefix_map_common<M>
+ {
+ typedef typename prefix_map_common<M>::value_type value_type;
+
+ prefix_map_impl (): prefix_map_common<M> (D) {}
+ prefix_map_impl (std::initializer_list<value_type> i)
+ : prefix_map_common<M> (std::move (i), D) {}
+ };
+
+ template <typename K,
+ typename T,
+ typename compare_prefix<K>::delimiter_type D>
+ using prefix_map = prefix_map_impl<std::map<K, T, compare_prefix<K>>, D>;
+
+ template <typename K,
+ typename T,
+ typename compare_prefix<K>::delimiter_type D>
+ using prefix_multimap =
+ prefix_map_impl<std::multimap<K, T, compare_prefix<K>>, D>;
+}
+
+#include <butl/prefix-map.txx>
+
+#endif // BUTL_PREFIX_MAP
diff --git a/butl/prefix-map.txx b/butl/prefix-map.txx
new file mode 100644
index 0000000..9ead579
--- /dev/null
+++ b/butl/prefix-map.txx
@@ -0,0 +1,39 @@
+// file : butl/prefix-map.txx -*- C++ -*-
+// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
+// license : MIT; see accompanying LICENSE file
+
+namespace butl
+{
+ template <typename M>
+ auto prefix_map_common<M>::
+ find_prefix (const key_type& k) -> std::pair<iterator, iterator>
+ {
+ std::pair<iterator, iterator> r;
+ r.first = this->lower_bound (k);
+
+ for (r.second = r.first; r.second != this->end (); ++r.second)
+ {
+ if (!this->key_comp ().prefix (k, r.second->first))
+ break;
+ }
+
+ return r;
+ }
+
+ template <typename M>
+ auto prefix_map_common<M>::
+ find_prefix (const key_type& k) const ->
+ std::pair<const_iterator, const_iterator>
+ {
+ std::pair<const_iterator, const_iterator> r;
+ r.first = this->lower_bound (k);
+
+ for (r.second = r.first; r.second != this->end (); ++r.second)
+ {
+ if (!this->key_comp ().prefix (k, r.second->first))
+ break;
+ }
+
+ return r;
+ }
+}
diff --git a/tests/buildfile b/tests/buildfile
new file mode 100644
index 0000000..19d85db
--- /dev/null
+++ b/tests/buildfile
@@ -0,0 +1,7 @@
+# file : tests/buildfile
+# copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
+# license : MIT; see accompanying LICENSE file
+
+d = prefix-map/
+.: $d
+include $d
diff --git a/tests/prefix-map/buildfile b/tests/prefix-map/buildfile
new file mode 100644
index 0000000..0fe9664
--- /dev/null
+++ b/tests/prefix-map/buildfile
@@ -0,0 +1,7 @@
+# file : tests/prefix-map/buildfile
+# copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
+# license : MIT; see accompanying LICENSE file
+
+exe{driver}: cxx{driver} ../../butl/lib{butl}
+
+include ../../butl/
diff --git a/tests/prefix-map/driver b/tests/prefix-map/driver
new file mode 100755
index 0000000..215146d
--- /dev/null
+++ b/tests/prefix-map/driver
Binary files differ
diff --git a/tests/prefix-map/driver.cxx b/tests/prefix-map/driver.cxx
new file mode 100644
index 0000000..2aa59c7
--- /dev/null
+++ b/tests/prefix-map/driver.cxx
@@ -0,0 +1,153 @@
+// file : tests/prefix-map/driver.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
+// license : MIT; see accompanying LICENSE file
+
+#include <string>
+#include <cassert>
+#include <iostream>
+
+#include <butl/prefix-map>
+
+using namespace std;
+using namespace butl;
+
+int
+main ()
+{
+ typedef prefix_map<string, int, '.'> pm;
+
+ {
+ const pm m;
+
+ {
+ auto r (m.find_prefix (""));
+ assert (r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("foo"));
+ assert (r.first == r.second);
+ }
+ }
+
+ {
+ pm m {{{"foo", 1}}};
+
+ {
+ auto r (m.find_prefix (""));
+ assert (r.first != r.second && r.first->second == 1 &&
+ ++r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("fo"));
+ assert (r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("fox"));
+ assert (r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("fooo"));
+ assert (r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("foo.bar"));
+ assert (r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("foo"));
+ assert (r.first != r.second && r.first->second == 1 &&
+ ++r.first == r.second);
+ }
+ }
+
+ {
+ pm m {{{"foo", 1}, {"bar", 2}}};
+
+ {
+ auto r (m.find_prefix (""));
+ assert (r.first != r.second && r.first->second == 2 &&
+ ++r.first != r.second && r.first->second == 1 &&
+ ++r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("fo"));
+ assert (r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("fox"));
+ assert (r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("fooo"));
+ assert (r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("foo.bar"));
+ assert (r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("foo"));
+ assert (r.first != r.second && r.first->second == 1 &&
+ ++r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("bar"));
+ assert (r.first != r.second && r.first->second == 2 &&
+ ++r.first == r.second);
+ }
+ }
+
+ {
+ pm m (
+ {{"boo", 1},
+ {"foo", 2}, {"fooa", 3}, {"foo.bar", 4}, {"foo.fox", 5},
+ {"xoo", 5}});
+
+ {
+ auto r (m.find_prefix ("fo"));
+ assert (r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("fox"));
+ assert (r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("fooo"));
+ assert (r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("foo.bar"));
+ assert (r.first != r.second && r.first->second == 4 &&
+ ++r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("foo.fox"));
+ assert (r.first != r.second && r.first->second == 5 &&
+ ++r.first == r.second);
+ }
+
+ {
+ auto r (m.find_prefix ("foo"));
+ assert (r.first != r.second && r.first->second == 2 &&
+ ++r.first != r.second && r.first->second == 4 &&
+ ++r.first != r.second && r.first->second == 5 &&
+ ++r.first == r.second);
+ }
+ }
+}
generated by cgit v1.1 at 2024-11-05 15:32:50 +0000