lttng: make session_storage::_array a unique_ptr to array

[lttng-tools.git] / src / bin / lttng / utils.hpp

diff --git a/src/bin/lttng/utils.hpp b/src/bin/lttng/utils.hpp
index c3b442056cc1ecc6d88d518089c3168ea00679e0..75b91df196d76257565a5c009ae3b654591cfb9d 100644 (file)
--- a/src/bin/lttng/utils.hpp
+++ b/src/bin/lttng/utils.hpp
@@ -9,6 +9,7 @@
 #define _LTTNG_UTILS_H
 
 #include <common/argpar/argpar.h>
+#include <common/container-wrapper.hpp>
 #include <common/dynamic-array.hpp>
 #include <common/make-unique-wrapper.hpp>
 
@@ -25,127 +26,119 @@ extern pid_t sessiond_pid;
 
 struct cmd_struct;
 
+namespace lttng {
+namespace cli {
+
 struct session_spec {
-       enum type {
+       enum class type {
                NAME,
                GLOB_PATTERN,
                ALL,
        };
 
-       type type;
+       explicit session_spec(type spec_type, const char *name_or_pattern = nullptr) noexcept :
+               type_(spec_type), value(name_or_pattern)
+       {
+       }
+
+       /* Disambiguate type enum from the member for buggy g++ versions. */
+       type type_;
        const char *value;
 };
 
-/*
- * We don't use a std::vector here because it would make a copy of the C array.
- */
-class session_list {
-       class iterator : public std::iterator<std::random_access_iterator_tag, std::size_t> {
-       public:
-               explicit iterator(session_list& list, std::size_t k) : _list(list), _index(k)
-               {
-               }
-
-               iterator& operator++() noexcept
-               {
-                       ++_index;
-                       return *this;
-               }
-
-               iterator& operator--() noexcept
-               {
-                       --_index;
-                       return *this;
-               }
-
-               iterator& operator++(int) noexcept
-               {
-                       _index++;
-                       return *this;
-               }
-
-               iterator& operator--(int) noexcept
-               {
-                       _index--;
-                       return *this;
-               }
-
-               bool operator==(iterator other) const noexcept
-               {
-                       return _index == other._index;
-               }
-
-               bool operator!=(iterator other) const noexcept
-               {
-                       return !(*this == other);
-               }
-
-               lttng_session& operator*() const noexcept
-               {
-                       return _list[_index];
-               }
-
-       private:
-               session_list& _list;
-               std::size_t _index;
-       };
+class session_list;
 
+namespace details {
+class session_storage {
 public:
-       session_list() : _sessions_count(0), _sessions(nullptr)
+       session_storage(lttng_session *raw_sessions, std::size_t sessions_count) :
+               _array(raw_sessions), _count(sessions_count)
        {
        }
 
-       session_list(session_list&& original, std::size_t new_count)
+       session_storage(session_storage&& original) :
+               _array(std::move(original._array)), _count(original._count)
        {
-               _sessions_count = new_count;
-               _sessions = std::move(original._sessions);
        }
 
-       session_list(struct lttng_session *raw_sessions, std::size_t raw_sessions_count)
+       session_storage(session_storage&& original, std::size_t new_count) :
+               _array(std::move(original._array)), _count(new_count)
        {
-               _sessions_count = raw_sessions_count;
-               _sessions.reset(raw_sessions);
        }
 
-       iterator begin() noexcept
+       std::unique_ptr<lttng_session[],
+                       lttng::memory::create_deleter_class<lttng_session, lttng::free>::deleter>
+               _array = nullptr;
+       std::size_t _count = 0;
+};
+
+class session_list_operations {
+public:
+       static lttng_session& get(const lttng::cli::details::session_storage& storage,
+                                 std::size_t index) noexcept
        {
-               return iterator(*this, 0);
+               return storage._array[index];
        }
 
-       iterator end() noexcept
+       static std::size_t size(const lttng::cli::details::session_storage& storage)
        {
-               return iterator(*this, _sessions_count);
+               return storage._count;
        }
+};
+} /* namespace details */
 
-       std::size_t size() const noexcept
+/*
+ * We don't use a std::vector here because it would make a copy of the C array.
+ */
+class session_list
+       : public lttng::utils::random_access_container_wrapper<details::session_storage,
+                                                              lttng_session&,
+                                                              details::session_list_operations> {
+public:
+       friend details::session_list_operations;
+
+       session_list() :
+               lttng::utils::random_access_container_wrapper<details::session_storage,
+                                                             lttng_session&,
+                                                             details::session_list_operations>(
+                       { nullptr, 0 })
        {
-               return _sessions_count;
        }
 
-       void resize(std::size_t new_size) noexcept
+       session_list(session_list&& original) :
+               lttng::utils::random_access_container_wrapper<details::session_storage,
+                                                             lttng_session&,
+                                                             details::session_list_operations>(
+                       std::move(original._container))
        {
-               _sessions_count = new_size;
        }
 
-       lttng_session& operator[](std::size_t index)
+       session_list(session_list&& original, std::size_t new_count) :
+               lttng::utils::random_access_container_wrapper<details::session_storage,
+                                                             lttng_session&,
+                                                             details::session_list_operations>(
+                       { std::move(original._container), new_count })
        {
-               LTTNG_ASSERT(index < _sessions_count);
-               return _sessions.get()[index];
        }
 
-       const lttng_session& operator[](std::size_t index) const
+       session_list(lttng_session *raw_sessions, std::size_t raw_sessions_count) :
+               lttng::utils::random_access_container_wrapper<details::session_storage,
+                                                             lttng_session&,
+                                                             details::session_list_operations>(
+                       { raw_sessions, raw_sessions_count })
        {
-               LTTNG_ASSERT(index < _sessions_count);
-               return _sessions.get()[index];
        }
 
-private:
-       std::size_t _sessions_count;
-       std::unique_ptr<lttng_session,
-                       lttng::details::create_unique_class<lttng_session, lttng::free>>
-               _sessions;
+       void resize(std::size_t new_size) noexcept
+       {
+               _container._count = new_size;
+       }
 };
 
+lttng::cli::session_list list_sessions(const struct session_spec& spec);
+} /* namespace cli */
+} /* namespace lttng */
+
 char *get_session_name(void);
 char *get_session_name_quiet(void);
 void list_commands(struct cmd_struct *commands, FILE *ofp);
@@ -186,6 +179,4 @@ int print_trace_archive_location(const struct lttng_trace_archive_location *loca
 int validate_exclusion_list(const char *event_name,
                            const struct lttng_dynamic_pointer_array *exclusions);
 
-session_list list_sessions(const struct session_spec& spec);
-
 #endif /* _LTTNG_UTILS_H */