nghttpx: Trie based routing

src/Makefile.am

@@ -128,6 +128,7 @@ NGHTTPX_SRCS = \
 	shrpx_worker_process.cc shrpx_worker_process.h \
 	shrpx_process.h \
 	shrpx_signal.cc shrpx_signal.h \
+	shrpx_router.cc shrpx_router.h \
 	buffer.h memchunk.h template.h
 
 if HAVE_SPDYLAY

src/shrpx.cc

@@ -2370,6 +2370,8 @@ int main(int argc, char **argv) {
 
     DownstreamAddrGroup g("/");
     g.addrs.push_back(std::move(addr));
+    mod_config()->router.add_route(g.pattern.get(), 1,
+                                   get_config()->downstream_addr_groups.size());
     mod_config()->downstream_addr_groups.push_back(std::move(g));
   } else if (get_config()->http2_proxy || get_config()->client_proxy) {
     // We don't support host mapping in these cases.  Move all
@@ -2381,6 +2383,9 @@ int main(int argc, char **argv) {
     }
     std::vector<DownstreamAddrGroup>().swap(
         mod_config()->downstream_addr_groups);
+    // maybe not necessary?
+    mod_config()->router.add_route(catch_all.pattern.get(), 1,
+                                   get_config()->downstream_addr_groups.size());
     mod_config()->downstream_addr_groups.push_back(std::move(catch_all));
   }
 
@@ -2391,11 +2396,11 @@ int main(int argc, char **argv) {
   ssize_t catch_all_group = -1;
   for (size_t i = 0; i < mod_config()->downstream_addr_groups.size(); ++i) {
     auto &g = mod_config()->downstream_addr_groups[i];
-    if (g.pattern == "/") {
+    if (util::streq(g.pattern.get(), "/")) {
       catch_all_group = i;
     }
     if (LOG_ENABLED(INFO)) {
-      LOG(INFO) << "Host-path pattern: group " << i << ": '" << g.pattern
+      LOG(INFO) << "Host-path pattern: group " << i << ": '" << g.pattern.get()
                 << "'";
       for (auto &addr : g.addrs) {
         LOG(INFO) << "group " << i << " -> " << addr.host.get()

src/shrpx_client_handler.cc

@@ -635,18 +635,20 @@ ClientHandler::get_downstream_connection(Downstream *downstream) {
     //  have dealt with proxy case already, just use catch-all group.
     group = catch_all;
   } else {
+    auto &router = get_config()->router;
     if (!downstream->get_request_http2_authority().empty()) {
       group = match_downstream_addr_group(
-          downstream->get_request_http2_authority(),
+          router, downstream->get_request_http2_authority(),
           downstream->get_request_path(), groups, catch_all);
     } else {
       auto h = downstream->get_request_header(http2::HD_HOST);
       if (h) {
-        group = match_downstream_addr_group(
+        group = match_downstream_addr_group(router, h->value,
-            h->value, downstream->get_request_path(), groups, catch_all);
+                                            downstream->get_request_path(),
-      } else {
-        group = match_downstream_addr_group("", downstream->get_request_path(),
                                             groups, catch_all);
+      } else {
+        group = match_downstream_addr_group(
+            router, "", downstream->get_request_path(), groups, catch_all);
       }
     }
   }

src/shrpx_config.cc

@@ -79,9 +79,9 @@ TicketKeys::~TicketKeys() {
 }
 
 DownstreamAddr::DownstreamAddr(const DownstreamAddr &other)
-    : addr(other.addr), host(other.host ? strcopy(other.host.get()) : nullptr),
+    : addr(other.addr), host(strcopy(other.host)),
-      hostport(other.hostport ? strcopy(other.hostport.get()) : nullptr),
+      hostport(strcopy(other.hostport)), port(other.port),
-      port(other.port), host_unix(other.host_unix) {}
+      host_unix(other.host_unix) {}
 
 DownstreamAddr &DownstreamAddr::operator=(const DownstreamAddr &other) {
   if (this == &other) {
@@ -89,14 +89,29 @@ DownstreamAddr &DownstreamAddr::operator=(const DownstreamAddr &other) {
   }
 
   addr = other.addr;
-  host = (other.host ? strcopy(other.host.get()) : nullptr);
+  host = strcopy(other.host);
-  hostport = (other.hostport ? strcopy(other.hostport.get()) : nullptr);
+  hostport = strcopy(other.hostport);
   port = other.port;
   host_unix = other.host_unix;
 
   return *this;
 }
 
+DownstreamAddrGroup::DownstreamAddrGroup(const DownstreamAddrGroup &other)
+    : pattern(strcopy(other.pattern)), addrs(other.addrs) {}
+
+DownstreamAddrGroup &DownstreamAddrGroup::
+operator=(const DownstreamAddrGroup &other) {
+  if (this == &other) {
+    return *this;
+  }
+
+  pattern = strcopy(other.pattern);
+  addrs = other.addrs;
+
+  return *this;
+}
+
 namespace {
 int split_host_port(char *host, size_t hostlen, uint16_t *port_ptr,
                     const char *hostport, size_t hostportlen) {
@@ -260,7 +275,6 @@ std::string read_passwd_from_file(const char *filename) {
   return line;
 }
 
-
 std::pair<std::string, std::string> parse_header(const char *optarg) {
   // We skip possible ":" at the start of optarg.
   const auto *colon = strchr(optarg + 1, ':');
@@ -576,7 +590,7 @@ void parse_mapping(const DownstreamAddr &addr, const char *src) {
       pattern += http2::normalize_path(slash, raw_pattern.second);
     }
     for (auto &g : mod_config()->downstream_addr_groups) {
-      if (g.pattern == pattern) {
+      if (g.pattern.get() == pattern) {
         g.addrs.push_back(addr);
         done = true;
         break;
@@ -587,6 +601,10 @@ void parse_mapping(const DownstreamAddr &addr, const char *src) {
     }
     DownstreamAddrGroup g(pattern);
     g.addrs.push_back(addr);
+
+    mod_config()->router.add_route(g.pattern.get(), strlen(g.pattern.get()),
+                                   get_config()->downstream_addr_groups.size());
+
     mod_config()->downstream_addr_groups.push_back(std::move(g));
   }
 }
@@ -2128,67 +2146,17 @@ int int_syslog_facility(const char *strfacility) {
 }
 
 namespace {
-template <typename InputIt>
+size_t
-bool path_match(const std::string &pattern, const std::string &host,
+match_downstream_addr_group_host(const Router &router, const std::string &host,
-                InputIt path_first, InputIt path_last) {
+                                 const char *path, size_t pathlen,
-  if (pattern.back() != '/') {
+                                 const std::vector<DownstreamAddrGroup> &groups,
-    return pattern.size() == host.size() + (path_last - path_first) &&
+                                 size_t catch_all) {
-           std::equal(std::begin(host), std::end(host), std::begin(pattern)) &&
+  if (pathlen == 0 || *path != '/') {
-           std::equal(path_first, path_last, std::begin(pattern) + host.size());
+    auto group = router.match(host, "/", 1);
-  }
-
-  if (pattern.size() >= host.size() &&
-      std::equal(std::begin(host), std::end(host), std::begin(pattern)) &&
-      util::startsWith(path_first, path_last, std::begin(pattern) + host.size(),
-                       std::end(pattern))) {
-    return true;
-  }
-
-  // If pattern ends with '/', and pattern and path matches without
-  // that slash, we consider they match to deal with request to the
-  // directory without trailing slash.  That is if pattern is "/foo/"
-  // and path is "/foo", we consider they match.
-
-  assert(!pattern.empty());
-  return pattern.size() - 1 == host.size() + (path_last - path_first) &&
-         std::equal(std::begin(host), std::end(host), std::begin(pattern)) &&
-         std::equal(path_first, path_last, std::begin(pattern) + host.size());
-}
-} // namespace
-
-namespace {
-template <typename InputIt>
-ssize_t match(const std::string &host, InputIt path_first, InputIt path_last,
-              const std::vector<DownstreamAddrGroup> &groups) {
-  ssize_t res = -1;
-  size_t best = 0;
-  for (size_t i = 0; i < groups.size(); ++i) {
-    auto &g = groups[i];
-    auto &pattern = g.pattern;
-    if (!path_match(pattern, host, path_first, path_last)) {
-      continue;
-    }
-    if (res == -1 || best < pattern.size()) {
-      best = pattern.size();
-      res = i;
-    }
-  }
-  return res;
-}
-} // namespace
-
-namespace {
-template <typename InputIt>
-size_t match_downstream_addr_group_host(
-    const std::string &host, InputIt path_first, InputIt path_last,
-    const std::vector<DownstreamAddrGroup> &groups, size_t catch_all) {
-  if (path_first == path_last || *path_first != '/') {
-    constexpr const char P[] = "/";
-    auto group = match(host, P, P + 1, groups);
     if (group != -1) {
       if (LOG_ENABLED(INFO)) {
         LOG(INFO) << "Found pattern with query " << host
-                  << ", matched pattern=" << groups[group].pattern;
+                  << ", matched pattern=" << groups[group].pattern.get();
       }
       return group;
     }
@@ -2197,25 +2165,24 @@ size_t match_downstream_addr_group_host(
 
   if (LOG_ENABLED(INFO)) {
     LOG(INFO) << "Perform mapping selection, using host=" << host
-              << ", path=" << std::string(path_first, path_last);
+              << ", path=" << std::string(path, pathlen);
   }
 
-  auto group = match(host, path_first, path_last, groups);
+  auto group = router.match(host, path, pathlen);
   if (group != -1) {
     if (LOG_ENABLED(INFO)) {
       LOG(INFO) << "Found pattern with query " << host
-                << std::string(path_first, path_last)
+                << std::string(path, pathlen)
-                << ", matched pattern=" << groups[group].pattern;
+                << ", matched pattern=" << groups[group].pattern.get();
     }
     return group;
   }
 
-  group = match("", path_first, path_last, groups);
+  group = router.match("", path, pathlen);
   if (group != -1) {
     if (LOG_ENABLED(INFO)) {
-      LOG(INFO) << "Found pattern with query "
+      LOG(INFO) << "Found pattern with query " << std::string(path, pathlen)
-                << std::string(path_first, path_last)
+                << ", matched pattern=" << groups[group].pattern.get();
-                << ", matched pattern=" << groups[group].pattern;
     }
     return group;
   }
@@ -2227,9 +2194,11 @@ size_t match_downstream_addr_group_host(
 }
 } // namespace
 
-size_t match_downstream_addr_group(
+size_t
-    const std::string &hostport, const std::string &raw_path,
+match_downstream_addr_group(const Router &router, const std::string &hostport,
-    const std::vector<DownstreamAddrGroup> &groups, size_t catch_all) {
+                            const std::string &raw_path,
+                            const std::vector<DownstreamAddrGroup> &groups,
+                            size_t catch_all) {
   if (std::find(std::begin(hostport), std::end(hostport), '/') !=
       std::end(hostport)) {
     // We use '/' specially, and if '/' is included in host, it breaks
@@ -2239,11 +2208,11 @@ size_t match_downstream_addr_group(
 
   auto fragment = std::find(std::begin(raw_path), std::end(raw_path), '#');
   auto query = std::find(std::begin(raw_path), fragment, '?');
-  auto path_first = std::begin(raw_path);
+  auto path = raw_path.c_str();
-  auto path_last = query;
+  auto pathlen = query - std::begin(raw_path);
 
   if (hostport.empty()) {
-    return match_downstream_addr_group_host(hostport, path_first, path_last,
+    return match_downstream_addr_group_host(router, hostport, path, pathlen,
                                             groups, catch_all);
   }
 
@@ -2267,7 +2236,7 @@ size_t match_downstream_addr_group(
   }
 
   util::inp_strlower(host);
-  return match_downstream_addr_group_host(host, path_first, path_last, groups,
+  return match_downstream_addr_group_host(router, host, path, pathlen, groups,
                                           catch_all);
 }
 

src/shrpx_config.h

@@ -50,6 +50,7 @@
 
 #include <nghttp2/nghttp2.h>
 
+#include "shrpx_router.h"
 #include "template.h"
 
 using namespace nghttp2;
@@ -229,8 +230,13 @@ struct DownstreamAddr {
 };
 
 struct DownstreamAddrGroup {
-  DownstreamAddrGroup(std::string pattern) : pattern(std::move(pattern)) {}
+  DownstreamAddrGroup(const std::string &pattern) : pattern(strcopy(pattern)) {}
-  std::string pattern;
+  DownstreamAddrGroup(const DownstreamAddrGroup &other);
+  DownstreamAddrGroup(DownstreamAddrGroup &&) = default;
+  DownstreamAddrGroup &operator=(const DownstreamAddrGroup &other);
+  DownstreamAddrGroup &operator=(DownstreamAddrGroup &&) = default;
+
+  std::unique_ptr<char[]> pattern;
   std::vector<DownstreamAddr> addrs;
 };
 
@@ -272,6 +278,7 @@ struct Config {
   Address downstream_http_proxy_addr;
   Address session_cache_memcached_addr;
   Address tls_ticket_key_memcached_addr;
+  Router router;
   std::chrono::seconds tls_session_timeout;
   ev_tstamp http2_upstream_read_timeout;
   ev_tstamp upstream_read_timeout;
@@ -442,24 +449,6 @@ std::pair<std::string, std::string> parse_header(const char *optarg);
 
 std::vector<LogFragment> parse_log_format(const char *optarg);
 
-// Returns a copy of NULL-terminated string [first, last).
-template <typename InputIt>
-std::unique_ptr<char[]> strcopy(InputIt first, InputIt last) {
-  auto res = make_unique<char[]>(last - first + 1);
-  *std::copy(first, last, res.get()) = '\0';
-  return res;
-}
-
-// Returns a copy of NULL-terminated string |val|.
-inline std::unique_ptr<char[]> strcopy(const char *val) {
-  return strcopy(val, val + strlen(val));
-}
-
-// Returns a copy of val.c_str().
-inline std::unique_ptr<char[]> strcopy(const std::string &val) {
-  return strcopy(std::begin(val), std::end(val));
-}
-
 // Returns string for syslog |facility|.
 const char *str_syslog_facility(int facility);
 
@@ -483,7 +472,7 @@ read_tls_ticket_key_file(const std::vector<std::string> &files,
 // group.  The catch-all group index is given in |catch_all|.  All
 // patterns are given in |groups|.
 size_t match_downstream_addr_group(
-    const std::string &hostport, const std::string &path,
+    const Router &router, const std::string &hostport, const std::string &path,
     const std::vector<DownstreamAddrGroup> &groups, size_t catch_all);
 
 } // namespace shrpx

src/shrpx_config_test.cc

@@ -235,56 +235,112 @@ void test_shrpx_config_match_downstream_addr_group(void) {
       {"nghttp2.org/delta%3A"},
       {"www.nghttp2.org/"},
       {"[::1]/"},
+      {"nghttp2.org/alpha/bravo/delta"},
+      // Check that match is done in the single node
+      {"example.com/alpha/bravo"},
+      {"192.168.0.1/alpha/"},
   };
 
-  CU_ASSERT(0 == match_downstream_addr_group("nghttp2.org", "/", groups, 255));
+  Router router;
+
+  for (size_t i = 0; i < groups.size(); ++i) {
+    auto &g = groups[i];
+    router.add_route(g.pattern.get(), strlen(g.pattern.get()), i);
+  }
+
+  CU_ASSERT(0 == match_downstream_addr_group(router, "nghttp2.org", "/", groups,
+                                             255));
 
   // port is removed
-  CU_ASSERT(0 ==
+  CU_ASSERT(0 == match_downstream_addr_group(router, "nghttp2.org:8080", "/",
-            match_downstream_addr_group("nghttp2.org:8080", "/", groups, 255));
+                                             groups, 255));
 
   // host is case-insensitive
-  CU_ASSERT(4 == match_downstream_addr_group("WWW.nghttp2.org", "/alpha",
+  CU_ASSERT(4 == match_downstream_addr_group(router, "WWW.nghttp2.org",
-                                             groups, 255));
+                                             "/alpha", groups, 255));
 
-  CU_ASSERT(1 == match_downstream_addr_group("nghttp2.org", "/alpha/bravo/",
+  CU_ASSERT(1 == match_downstream_addr_group(router, "nghttp2.org",
-                                             groups, 255));
+                                             "/alpha/bravo/", groups, 255));
 
   // /alpha/bravo also matches /alpha/bravo/
-  CU_ASSERT(1 == match_downstream_addr_group("nghttp2.org", "/alpha/bravo",
+  CU_ASSERT(1 == match_downstream_addr_group(router, "nghttp2.org",
-                                             groups, 255));
+                                             "/alpha/bravo", groups, 255));
 
   // path part is case-sensitive
-  CU_ASSERT(0 == match_downstream_addr_group("nghttp2.org", "/Alpha/bravo",
+  CU_ASSERT(0 == match_downstream_addr_group(router, "nghttp2.org",
-                                             groups, 255));
+                                             "/Alpha/bravo", groups, 255));
 
-  CU_ASSERT(1 == match_downstream_addr_group(
+  CU_ASSERT(1 == match_downstream_addr_group(router, "nghttp2.org",
-                     "nghttp2.org", "/alpha/bravo/charlie", groups, 255));
+                                             "/alpha/bravo/charlie", groups,
+                                             255));
 
-  CU_ASSERT(2 == match_downstream_addr_group("nghttp2.org", "/alpha/charlie",
+  CU_ASSERT(2 == match_downstream_addr_group(router, "nghttp2.org",
-                                             groups, 255));
+                                             "/alpha/charlie", groups, 255));
 
   // pattern which does not end with '/' must match its entirely.  So
   // this matches to group 0, not group 2.
-  CU_ASSERT(0 == match_downstream_addr_group("nghttp2.org", "/alpha/charlie/",
+  CU_ASSERT(0 == match_downstream_addr_group(router, "nghttp2.org",
-                                             groups, 255));
+                                             "/alpha/charlie/", groups, 255));
+
+  CU_ASSERT(255 == match_downstream_addr_group(router, "example.org", "/",
+                                               groups, 255));
+
+  CU_ASSERT(255 == match_downstream_addr_group(router, "", "/", groups, 255));
 
   CU_ASSERT(255 ==
-            match_downstream_addr_group("example.org", "/", groups, 255));
+            match_downstream_addr_group(router, "", "alpha", groups, 255));
 
-  CU_ASSERT(255 == match_downstream_addr_group("", "/", groups, 255));
+  CU_ASSERT(255 ==
-
+            match_downstream_addr_group(router, "foo/bar", "/", groups, 255));
-  CU_ASSERT(255 == match_downstream_addr_group("", "alpha", groups, 255));
-
-  CU_ASSERT(255 == match_downstream_addr_group("foo/bar", "/", groups, 255));
 
   // If path is "*", only match with host + "/".
-  CU_ASSERT(0 == match_downstream_addr_group("nghttp2.org", "*", groups, 255));
+  CU_ASSERT(0 == match_downstream_addr_group(router, "nghttp2.org", "*", groups,
+                                             255));
 
-  CU_ASSERT(5 == match_downstream_addr_group("[::1]", "/", groups, 255));
+  CU_ASSERT(5 ==
-  CU_ASSERT(5 == match_downstream_addr_group("[::1]:8080", "/", groups, 255));
+            match_downstream_addr_group(router, "[::1]", "/", groups, 255));
-  CU_ASSERT(255 == match_downstream_addr_group("[::1", "/", groups, 255));
+  CU_ASSERT(
-  CU_ASSERT(255 == match_downstream_addr_group("[::1]8000", "/", groups, 255));
+      5 == match_downstream_addr_group(router, "[::1]:8080", "/", groups, 255));
+  CU_ASSERT(255 ==
+            match_downstream_addr_group(router, "[::1", "/", groups, 255));
+  CU_ASSERT(255 ==
+            match_downstream_addr_group(router, "[::1]8000", "/", groups, 255));
+
+  // Check the case where adding route extends tree
+  CU_ASSERT(6 == match_downstream_addr_group(
+                     router, "nghttp2.org", "/alpha/bravo/delta", groups, 255));
+
+  CU_ASSERT(1 == match_downstream_addr_group(router, "nghttp2.org",
+                                             "/alpha/bravo/delta/", groups,
+                                             255));
+
+  // Check the case where query is done in a single node
+  CU_ASSERT(7 == match_downstream_addr_group(router, "example.com",
+                                             "/alpha/bravo", groups, 255));
+
+  CU_ASSERT(255 == match_downstream_addr_group(router, "example.com",
+                                               "/alpha/bravo/", groups, 255));
+
+  CU_ASSERT(255 == match_downstream_addr_group(router, "example.com", "/alpha",
+                                               groups, 255));
+
+  // Check the case where quey is done in a single node
+  CU_ASSERT(8 == match_downstream_addr_group(router, "192.168.0.1", "/alpha",
+                                             groups, 255));
+
+  CU_ASSERT(8 == match_downstream_addr_group(router, "192.168.0.1", "/alpha/",
+                                             groups, 255));
+
+  CU_ASSERT(8 == match_downstream_addr_group(router, "192.168.0.1",
+                                             "/alpha/bravo", groups, 255));
+
+  CU_ASSERT(255 == match_downstream_addr_group(router, "192.168.0.1", "/alph",
+                                               groups, 255));
+
+  CU_ASSERT(255 == match_downstream_addr_group(router, "192.168.0.1", "/",
+                                               groups, 255));
+
+  router.dump();
 }
 
 } // namespace shrpx

src/shrpx_router.cc

@@ -0,0 +1,291 @@
+/*
+ * nghttp2 - HTTP/2 C Library
+ *
+ * Copyright (c) 2015 Tatsuhiro Tsujikawa
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include "shrpx_router.h"
+
+#include "shrpx_config.h"
+
+namespace shrpx {
+
+RNode::RNode() : s(nullptr), len(0), index(-1) {}
+
+RNode::RNode(const char *s, size_t len, size_t index)
+    : s(s), len(len), index(index) {}
+
+Router::Router() : root_{} {}
+
+namespace {
+RNode *find_next_node(const RNode *node, char c) {
+  auto itr = std::lower_bound(std::begin(node->next), std::end(node->next), c,
+                              [](const std::unique_ptr<RNode> &lhs,
+                                 const char c) { return lhs->s[0] < c; });
+  if (itr == std::end(node->next) || (*itr)->s[0] != c) {
+    return nullptr;
+  }
+
+  return (*itr).get();
+}
+} // namespace
+
+namespace {
+void add_next_node(RNode *node, std::unique_ptr<RNode> new_node) {
+  auto itr = std::lower_bound(std::begin(node->next), std::end(node->next),
+                              new_node->s[0],
+                              [](const std::unique_ptr<RNode> &lhs,
+                                 const char c) { return lhs->s[0] < c; });
+  node->next.insert(itr, std::move(new_node));
+}
+} // namespace
+
+void Router::add_node(RNode *node, const char *pattern, size_t patlen,
+                      size_t index) {
+  auto new_node = make_unique<RNode>(pattern, patlen, index);
+  add_next_node(node, std::move(new_node));
+}
+
+bool Router::add_route(const char *pattern, size_t patlen, size_t index) {
+  auto node = &root_;
+  size_t i = 0;
+
+  for (;;) {
+    auto next_node = find_next_node(node, pattern[i]);
+    if (next_node == nullptr) {
+      add_node(node, pattern + i, patlen - i, index);
+      return true;
+    }
+
+    node = next_node;
+
+    auto slen = patlen - i;
+    auto s = pattern + i;
+    auto n = std::min(node->len, slen);
+    size_t j;
+    for (j = 0; j < n && node->s[j] == s[j]; ++j)
+      ;
+    if (j == n) {
+      // The common prefix was matched
+      if (slen == node->len) {
+        // Complete match
+        if (node->index != -1) {
+          // Don't allow duplicate
+          return false;
+        }
+        node->index = index;
+        return true;
+      }
+
+      if (slen > node->len) {
+        // We still have pattern to add
+        i += j;
+
+        continue;
+      }
+    }
+
+    if (node->len > j) {
+      // node must be split into 2 nodes.  new_node is now the child
+      // of node.
+      auto new_node =
+          make_unique<RNode>(&node->s[j], node->len - j, node->index);
+      std::swap(node->next, new_node->next);
+
+      node->len = j;
+      node->index = -1;
+
+      add_next_node(node, std::move(new_node));
+
+      if (slen == j) {
+        node->index = index;
+        return true;
+      }
+    }
+
+    i += j;
+
+    assert(patlen > i);
+    add_node(node, pattern + i, patlen - i, index);
+
+    return true;
+  }
+}
+
+namespace {
+const RNode *match_complete(size_t *offset, const RNode *node,
+                            const char *first, const char *last) {
+  *offset = 0;
+
+  if (first == last) {
+    return node;
+  }
+
+  auto p = first;
+
+  for (;;) {
+    auto next_node = find_next_node(node, *p);
+    if (next_node == nullptr) {
+      return nullptr;
+    }
+
+    node = next_node;
+
+    auto n = std::min(node->len, static_cast<size_t>(last - p));
+    if (memcmp(node->s, p, n) != 0) {
+      return nullptr;
+    }
+    p += n;
+    if (p == last) {
+      *offset = n;
+      return node;
+    }
+  }
+}
+} // namespace
+
+namespace {
+const RNode *match_partial(const RNode *node, size_t offset, const char *first,
+                           const char *last) {
+  if (first == last) {
+    if (node->len == offset) {
+      return node;
+    }
+    return nullptr;
+  }
+
+  auto p = first;
+
+  const RNode *found_node = nullptr;
+
+  if (offset > 0) {
+    auto n = std::min(node->len - offset, static_cast<size_t>(last - first));
+    if (memcmp(node->s + offset, first, n) != 0) {
+      return nullptr;
+    }
+
+    p += n;
+
+    if (p == last) {
+      if (node->len == offset + n) {
+        if (node->index != -1) {
+          return node;
+        }
+
+        return nullptr;
+      }
+
+      if (node->index != -1 && offset + n + 1 == node->len &&
+          node->s[node->len - 1] == '/') {
+        return node;
+      }
+
+      return nullptr;
+    }
+
+    if (node->index != -1 && node->s[node->len - 1] == '/') {
+      found_node = node;
+    }
+
+    assert(node->len == offset + n);
+  }
+
+  for (;;) {
+    auto next_node = find_next_node(node, *p);
+    if (next_node == nullptr) {
+      return found_node;
+    }
+
+    node = next_node;
+
+    auto n = std::min(node->len, static_cast<size_t>(last - p));
+    if (memcmp(node->s, p, n) != 0) {
+      return found_node;
+    }
+
+    p += n;
+
+    if (p == last) {
+      if (node->len == n) {
+        // Complete match with this node
+        if (node->index != -1) {
+          return node;
+        }
+
+        return found_node;
+      }
+
+      // We allow match without trailing "/" at the end of pattern.
+      // So, if pattern ends with '/', and pattern and path matches
+      // without that slash, we consider they match to deal with
+      // request to the directory without trailing slash.  That is if
+      // pattern is "/foo/" and path is "/foo", we consider they
+      // match.
+      if (node->index != -1 && n + 1 == node->len && node->s[n] == '/') {
+        return node;
+      }
+
+      return found_node;
+    }
+
+    // This is the case when pattern which ends with "/" is included
+    // in query.
+    if (node->index != -1 && node->s[node->len - 1] == '/') {
+      found_node = node;
+    }
+
+    assert(node->len == n);
+  }
+}
+} // namespace
+
+ssize_t Router::match(const std::string &host, const char *path,
+                      size_t pathlen) const {
+  const RNode *node;
+  size_t offset;
+
+  node =
+      match_complete(&offset, &root_, host.c_str(), host.c_str() + host.size());
+  if (node == nullptr) {
+    return -1;
+  }
+
+  node = match_partial(node, offset, path, path + pathlen);
+  if (node == nullptr || node == &root_) {
+    return -1;
+  }
+
+  return node->index;
+}
+
+namespace {
+void dump_node(const RNode *node, int depth) {
+  fprintf(stderr, "%*ss='%.*s', len=%zu, index=%zd\n", depth, "",
+          (int)node->len, node->s, node->len, node->index);
+  for (auto &nd : node->next) {
+    dump_node(nd.get(), depth + 4);
+  }
+}
+} // namespace
+
+void Router::dump() const { dump_node(&root_, 0); }
+
+} // namespace shrpx

src/shrpx_router.h

@@ -0,0 +1,76 @@
+/*
+ * nghttp2 - HTTP/2 C Library
+ *
+ * Copyright (c) 2015 Tatsuhiro Tsujikawa
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#ifndef SHRPX_ROUTER_H
+#define SHRPX_ROUTER_H
+
+#include "shrpx.h"
+
+#include <vector>
+#include <memory>
+
+namespace shrpx {
+
+struct RNode {
+  RNode();
+  RNode(const char *s, size_t len, size_t index);
+  RNode(RNode &&) = default;
+  RNode(const RNode &) = delete;
+  RNode &operator=(RNode &&) = default;
+  RNode &operator=(const RNode &) = delete;
+
+  // Next RNode, sorted by s[0].
+  std::vector<std::unique_ptr<RNode>> next;
+  // Stores pointer to the string this node represents.  Not
+  // NULL-terminated.
+  const char *s;
+  // Length of |s|
+  size_t len;
+  // Index of pattern if match ends in this node.  Note that we don't
+  // store duplicated pattern.
+  ssize_t index;
+};
+
+class Router {
+public:
+  Router();
+  // Adds route |pattern| of size |patlen| with its |index|.
+  bool add_route(const char *pattern, size_t patlen, size_t index);
+  // Returns the matched index of pattern.  -1 if there is no match.
+  ssize_t match(const std::string &host, const char *path,
+                size_t pathlen) const;
+
+  void add_node(RNode *node, const char *pattern, size_t patlen, size_t index);
+
+  void dump() const;
+
+private:
+  // The root node of Patricia tree.  This is special node and its s
+  // field is nulptr, and len field is 0.
+  RNode root_;
+};
+
+} // namespace shrpx
+
+#endif // SHRPX_ROUTER_H

src/template.h

@@ -170,6 +170,31 @@ constexpr double operator"" _h(unsigned long long h) { return h * 60 * 60; }
 
 constexpr double operator"" _min(unsigned long long min) { return min * 60; }
 
+// Returns a copy of NULL-terminated string [first, last).
+template <typename InputIt>
+std::unique_ptr<char[]> strcopy(InputIt first, InputIt last) {
+  auto res = make_unique<char[]>(last - first + 1);
+  *std::copy(first, last, res.get()) = '\0';
+  return res;
+}
+
+// Returns a copy of NULL-terminated string |val|.
+inline std::unique_ptr<char[]> strcopy(const char *val) {
+  return strcopy(val, val + strlen(val));
+}
+
+// Returns a copy of val.c_str().
+inline std::unique_ptr<char[]> strcopy(const std::string &val) {
+  return strcopy(std::begin(val), std::end(val));
+}
+
+inline std::unique_ptr<char[]> strcopy(const std::unique_ptr<char[]> &val) {
+  if (!val) {
+    return nullptr;
+  }
+  return strcopy(val.get());
+}
+
 } // namespace nghttp2
 
 #endif // TEMPLATE_H