Adding upstream version 2.4.1.upstream/2.4.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 221 insertions, 0 deletions

diff --git a/src/lib/hooks/server_hooks.cc b/src/lib/hooks/server_hooks.cc
new file mode 100644
index 0000000..5ca1a50
--- /dev/null
+++ b/src/lib/hooks/server_hooks.cc
@@ -0,0 +1,221 @@
+// Copyright (C) 2013-2018 Internet Systems Consortium, Inc. ("ISC")
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#include <config.h>
+
+#include <exceptions/exceptions.h>
+#include <hooks/hooks_log.h>
+#include <hooks/server_hooks.h>
+
+#include <algorithm>
+#include <utility>
+#include <vector>
+
+using namespace std;
+using namespace isc;
+
+namespace isc {
+namespace hooks {
+
+// Constructor - register the pre-defined hooks and check that the indexes
+// assigned to them are as expected.
+//
+// Note that there are no logging messages here or in registerHooks().  The
+// recommended way to initialize hook names is to use static initialization.
+// Here, a static object is declared in a file outside of any function or
+// method.  As a result, it is instantiated and its constructor run before the
+// program starts.  By putting calls to ServerHooks::registerHook() in there,
+// hooks names are already registered when the program runs.  However, at that
+// point, the logging system is not initialized, so messages are unable to
+// be output.
+
+ServerHooks::ServerHooks() {
+    initialize();
+}
+
+// Register a hook.  The index assigned to the hook is the current number
+// of entries in the collection, so ensuring that hook indexes are unique
+// and non-negative.
+
+int
+ServerHooks::registerHook(const string& name) {
+
+    // Determine index for the new element and insert.
+    int index = hooks_.size();
+    pair<HookCollection::iterator, bool> result =
+        hooks_.insert(make_pair(name, index));
+
+    /// @todo: We also need to call CalloutManager::ensureVectorSize(), so it
+    /// adjusts its vector. Since CalloutManager is not a singleton, there's
+    /// no getInstance() or similar. Also, CalloutManager uses ServerHooks,
+    /// so such a call would induce circular dependencies. Ugh.
+
+    if (!result.second) {
+
+        // There's a problem with hook libraries that need to be linked with
+        // libdhcpsrv. For example host_cmds hook library requires host
+        // parser, so it needs to be linked with libdhcpsrv. However, when
+        // unit-tests are started, the hook points are not registered.
+        // When the library is loaded new hook points are registered.
+        // This causes issues in the hooks framework, especially when
+        // LibraryManager::unloadLibrary() iterates through all hooks
+        // and then calls deregisterAllCallouts. This method gets
+        // hook_index that is greater than number of elements in
+        // hook_vector_ and then we have a read past the array boundary.
+        /// @todo: See ticket 5251 and 5208 for details.
+        return (getIndex(name));
+
+        // New element was not inserted because an element with the same name
+        // already existed.
+        //isc_throw(DuplicateHook, "hook with name " << name <<
+        //         " is already registered");
+    }
+
+    // Element was inserted, so add to the inverse hooks collection.
+    inverse_hooks_[index] = name;
+
+    // ... and return numeric index.
+    return (index);
+}
+
+// Set ServerHooks object to initial state.
+
+void
+ServerHooks::initialize() {
+
+    // Clear out the name->index and index->name maps.
+    hooks_.clear();
+    inverse_hooks_.clear();
+    parking_lots_.reset(new ParkingLots());
+
+    // Register the pre-defined hooks.
+    int create = registerHook("context_create");
+    int destroy = registerHook("context_destroy");
+
+    // Check registration went as expected.
+    if ((create != CONTEXT_CREATE) || (destroy != CONTEXT_DESTROY)) {
+        isc_throw(Unexpected, "pre-defined hook indexes are not as expected. "
+                  "context_create: expected = " << CONTEXT_CREATE <<
+                  ", actual = " << create <<
+                  ". context_destroy: expected = " << CONTEXT_DESTROY <<
+                  ", actual = " << destroy);
+    }
+}
+
+// Reset ServerHooks object to initial state.
+
+void
+ServerHooks::reset() {
+
+    // Clear all hooks then initialize the pre-defined ones.
+    initialize();
+
+    // Log a warning - although this is done during testing, it should never be
+    // seen in a production system.
+    LOG_WARN(hooks_logger, HOOKS_HOOK_LIST_RESET);
+}
+
+// Find the name associated with a hook index.
+
+std::string
+ServerHooks::getName(int index) const {
+
+    // Get iterator to matching element.
+    InverseHookCollection::const_iterator i = inverse_hooks_.find(index);
+    if (i == inverse_hooks_.end()) {
+        isc_throw(NoSuchHook, "hook index " << index << " is not recognized");
+    }
+
+    return (i->second);
+}
+
+// Find the index associated with a hook name.
+
+int
+ServerHooks::getIndex(const string& name) const {
+
+    // Get iterator to matching element.
+    HookCollection::const_iterator i = hooks_.find(name);
+    if (i == hooks_.end()) {
+        isc_throw(NoSuchHook, "hook name " << name << " is not recognized");
+    }
+
+    return (i->second);
+}
+
+int
+ServerHooks::findIndex(const std::string& name) const {
+    // Get iterator to matching element.
+    auto i = hooks_.find(name);
+    return ((i == hooks_.end()) ? -1 : i->second);
+}
+
+// Return vector of hook names.  The names are not sorted - it is up to the
+// caller to perform sorting if required.
+
+vector<string>
+ServerHooks::getHookNames() const {
+
+    vector<string> names;
+    HookCollection::const_iterator i;
+    for (i = hooks_.begin(); i != hooks_.end(); ++i) {
+        names.push_back(i->first);
+    }
+
+    return (names);
+}
+
+// Return global ServerHooks object
+
+ServerHooks&
+ServerHooks::getServerHooks() {
+    return (*getServerHooksPtr());
+}
+
+ServerHooksPtr
+ServerHooks::getServerHooksPtr() {
+    static ServerHooksPtr hooks(new ServerHooks());
+    return (hooks);
+}
+
+ParkingLotsPtr
+ServerHooks::getParkingLotsPtr() const {
+    return (parking_lots_);
+}
+
+ParkingLotPtr
+ServerHooks::getParkingLotPtr(const int hook_index) {
+    return (parking_lots_->getParkingLotPtr(hook_index));
+}
+
+ParkingLotPtr
+ServerHooks::getParkingLotPtr(const std::string& hook_name) {
+    return (parking_lots_->getParkingLotPtr(getServerHooks().getIndex(hook_name)));
+}
+
+std::string
+ServerHooks::commandToHookName(const std::string& command_name) {
+    // Prefix the command name with a dollar sign.
+    std::string hook_name = std::string("$") + command_name;
+    // Replace all hyphens with underscores.
+    std::replace(hook_name.begin(), hook_name.end(), '-', '_');
+    return (hook_name);
+}
+
+std::string
+ServerHooks::hookToCommandName(const std::string& hook_name) {
+    if (!hook_name.empty() && hook_name.front() == '$') {
+        std::string command_name = hook_name.substr(1);
+        std::replace(command_name.begin(), command_name.end(), '_', '-');
+        return (command_name);
+    }
+    return ("");
+}
+
+
+
+} // namespace hooks
+} // namespace isc