re-add ipc::channel (TBD); use hpp instead of cpp to implement channel/route, cause it could visit the internal entities which in ipc.cpp

build/src.pro

@@ -23,12 +23,13 @@ HEADERS += \
     ../include/ipc.h \
     ../include/def.h \
     ../include/rw_lock.h \
-    ../include/tls_pointer.h
+    ../include/tls_pointer.h \
+    ../src/route.hpp \
+    ../src/channel.hpp
 
 SOURCES += \
     ../src/shm.cpp \
-    ../src/ipc.cpp \
-    ../src/route.cpp
+    ../src/ipc.cpp
 
 unix {
 

include/circ_queue.h

@@ -6,6 +6,7 @@
 #include <utility>
 #include <algorithm>
 #include <atomic>
+#include <tuple>
 
 #include "def.h"
 #include "circ_elem_array.h"
@@ -108,40 +109,42 @@ public:
         return true;
     }
 
-    template <typename QArr, typename At>
-    static T multi_pop(QArr& ques, std::size_t size, At&& at) {
-        if (size == 0) throw std::invalid_argument { "Invalid size." };
+    template <typename F>
+    static queue* multi_wait_for(F&& upd) {
         while (1) {
+            auto [ques, size] = upd();
+            if (size == 0) throw std::invalid_argument { "Invalid size." };
             for (std::size_t i = 0; i < size; ++i) {
-                queue* cq = at(ques, i);
-                if (cq->elems_ == nullptr) throw std::logic_error {
+                queue* que = ques[i];
+                if (que->elems_ == nullptr) throw std::logic_error {
                     "This queue hasn't attached any elem_array."
                 };
-                if (cq->cursor_ != cq->elems_->cursor()) {
-                    auto item_ptr = static_cast<T*>(cq->elems_->take(cq->cursor_++));
-                    T item = std::move(*item_ptr);
-                    cq->elems_->put(item_ptr);
-                    return item;
+                if (que->cursor_ != que->elems_->cursor()) {
+                    return que;
                 }
             }
             std::this_thread::yield();
         }
     }
 
-    static T multi_pop(queue* ques, std::size_t size) {
-        if (ques == nullptr) throw std::invalid_argument { "Invalid ques pointer." };
-        return multi_pop(ques, size, [](queue* ques, std::size_t i) {
-            return ques + i;
-        });
+    static T pop(queue* que) {
+        if (que == nullptr) throw std::invalid_argument {
+            "Invalid ques pointer."
+        };
+        if (que->elems_ == nullptr) throw std::logic_error {
+            "This queue hasn't attached any elem_array."
+        };
+        auto item_ptr = static_cast<T*>(que->elems_->take(que->cursor_++));
+        T item = std::move(*item_ptr);
+        que->elems_->put(item_ptr);
+        return item;
     }
 
-    static T multi_pop(std::vector<queue*>& ques) {
-        return multi_pop(ques, ques.size(), [](auto& ques, std::size_t i) {
-            return ques[i];
-        });
+    T pop() {
+        return pop(multi_wait_for([this] {
+            return std::make_tuple(&this, 1);
+        }));
     }
-
-    T pop() { return multi_pop(this, 1); }
 };
 
 } // namespace circ

include/ipc.h

@@ -78,28 +78,43 @@ private:
     route_* p_;
 };
 
-///*
-// * class channel
-//*/
-//class IPC_EXPORT channel {
-//public:
-//    channel();
-//    channel(char const * name);
-//    channel(channel&& rhs);
+/*
+ * class channel
+ *
+ * You could use multi producers/servers/senders for sending messages to a channel,
+ * then all the consumers/clients/receivers which are receiving with this channel,
+ * would receive your sent messages.
+*/
+class IPC_EXPORT channel {
+public:
+    channel();
+    channel(char const * name);
+    channel(channel&& rhs);
 
-//    ~channel();
+    ~channel();
 
-//    void swap(channel& rhs);
-//    channel& operator=(channel rhs);
+    void swap(channel& rhs);
+    channel& operator=(channel rhs);
 
-//    bool         valid() const;
-//    char const * name () const;
+    bool         valid() const;
+    char const * name () const;
 
-//    channel clone() const;
+    channel clone() const;
 
-//private:
-//    class channel_;
-//    channel_* p_;
-//};
+    bool connect(char const * name);
+    void disconnect();
+
+    std::size_t recv_count() const;
+
+    bool send(void const * data, std::size_t size);
+    bool send(buff_t const & buff);
+    bool send(std::string const & str);
+
+    buff_t recv();
+
+private:
+    class channel_;
+    channel_* p_;
+};
 
 } // namespace ipc

src/channel.hpp

@@ -0,0 +1,120 @@
+#include "ipc.h"
+
+#include <atomic>
+#include <string>
+
+#include "def.h"
+#include "shm.h"
+
+namespace {
+
+using namespace ipc;
+
+struct ch_info_t {
+    std::atomic<uint_t<8>> ch_acc_; // only support 256 channels with one name
+};
+
+} // internal-linkage
+
+////////////////////////////////////////////////////////////////
+/// class channel implementation
+////////////////////////////////////////////////////////////////
+
+namespace ipc {
+
+class channel::channel_ : public pimpl<channel_> {
+public:
+    shm::handle h_;
+    route       r_;
+
+    ch_info_t* info() {
+        return static_cast<ch_info_t*>(h_.get());
+    }
+
+    auto& acc() {
+        return info()->ch_acc_;
+    }
+};
+
+channel::channel()
+    : p_(p_->make()) {
+}
+
+channel::channel(char const * name)
+    : channel() {
+    this->connect(name);
+}
+
+channel::channel(channel&& rhs)
+    : channel() {
+    swap(rhs);
+}
+
+channel::~channel() {
+    disconnect();
+    p_->clear();
+}
+
+void channel::swap(channel& rhs) {
+    std::swap(p_, rhs.p_);
+}
+
+channel& channel::operator=(channel rhs) {
+    swap(rhs);
+    return *this;
+}
+
+bool channel::valid() const {
+    return impl(p_)->h_.valid() && impl(p_)->r_.valid();
+}
+
+char const * channel::name() const {
+    std::string n { impl(p_)->h_.name() };
+    n.pop_back();
+    return n.c_str();
+}
+
+channel channel::clone() const {
+    return { name() };
+}
+
+bool channel::connect(char const * name) {
+    if (name == nullptr || name[0] == '\0') {
+        return false;
+    }
+    this->disconnect();
+    using namespace std::literals::string_literals;
+    if (!impl(p_)->h_.acquire((name + "_"s).c_str(), sizeof(ch_info_t))) {
+        return false;
+    }
+    auto cur_id = impl(p_)->acc().fetch_add(1, std::memory_order_relaxed);
+    impl(p_)->r_.connect((name + std::to_string(cur_id)).c_str());
+    return valid();
+}
+
+void channel::disconnect() {
+    impl(p_)->r_.disconnect();
+    impl(p_)->h_.release();
+}
+
+std::size_t channel::recv_count() const {
+    return 0;
+}
+
+bool channel::send(void const *data, std::size_t size) {
+    return false;
+}
+
+bool channel::send(buff_t const & buff) {
+    return false;
+}
+
+bool channel::send(std::string const & str) {
+    return false;
+}
+
+buff_t channel::recv() {
+    return {};
+}
+
+} // namespace ipc

src/ipc.cpp

@@ -42,6 +42,15 @@ inline std::atomic_size_t* acc_of(queue_t* que) {
     return reinterpret_cast<std::atomic_size_t*>(que->elems()) - 1;
 }
 
+inline auto& recv_cache() {
+    /*
+     * the performance of tls::pointer is not good enough
+     * so regardless of the mingw-crash-problem for the moment
+    */
+    thread_local std::unordered_map<decltype(msg_t::id_), buff_t> rc;
+    return rc;
+}
+
 } // internal-linkage
 
 namespace ipc {
@@ -130,8 +139,39 @@ bool send(handle_t h, void const * data, std::size_t size) {
     return true;
 }
 
-buff_t recv(handle_t h) {
-    return recv(&h, 1);
+template <typename F>
+buff_t updating_recv(F&& upd) {
+    auto& rc = recv_cache();
+    while(1) {
+        // pop a new message
+        auto msg = queue_t::pop(queue_t::multi_wait_for(upd));
+        // msg.remain_ may minus & abs(msg.remain_) < data_length
+        std::size_t remain = static_cast<std::size_t>(
+                             static_cast<int>(data_length) + msg.remain_);
+        // find cache with msg.id_
+        auto cache_it = rc.find(msg.id_);
+        if (cache_it == rc.end()) {
+            if (remain <= data_length) {
+                return make_buff(msg.data_, remain);
+            }
+            // cache the first message fragment
+            else rc.emplace(msg.id_, make_buff(msg.data_));
+        }
+        // has cached before this message
+        else {
+            auto& cache = cache_it->second;
+            // this is the last message fragment
+            if (msg.remain_ <= 0) {
+                cache.insert(cache.end(), msg.data_, msg.data_ + remain);
+                // finish this message, erase it from cache
+                auto buf = std::move(cache);
+                rc.erase(cache_it);
+                return buf;
+            }
+            // there are remain datas after this message
+            cache.insert(cache.end(), msg.data_, msg.data_ + data_length);
+        }
+    }
 }
 
 buff_t recv(handle_t const * hs, std::size_t size) {
@@ -146,41 +186,16 @@ buff_t recv(handle_t const * hs, std::size_t size) {
     if (q_arr.empty()) {
         return {};
     }
-    /*
-     * the performance of tls::pointer is not good enough
-     * so regardless of the mingw-crash-problem for the moment
-    */
-    thread_local std::unordered_map<decltype(msg_t::id_), buff_t> rcs;
-    while(1) {
-        // pop a new message
-        auto msg = queue_t::multi_pop(q_arr);
-        // msg.remain_ may minus & abs(msg.remain_) < data_length
-        std::size_t remain = static_cast<std::size_t>(
-                             static_cast<int>(data_length) + msg.remain_);
-        // find cache with msg.id_
-        auto cache_it = rcs.find(msg.id_);
-        if (cache_it == rcs.end()) {
-            if (remain <= data_length) {
-                return make_buff(msg.data_, remain);
-            }
-            // cache the first message fragment
-            else rcs.emplace(msg.id_, make_buff(msg.data_));
-        }
-        // has cached before this message
-        else {
-            auto& cache = cache_it->second;
-            // this is the last message fragment
-            if (msg.remain_ <= 0) {
-                cache.insert(cache.end(), msg.data_, msg.data_ + remain);
-                // finish this message, erase it from cache
-                auto buf = std::move(cache);
-                rcs.erase(cache_it);
-                return buf;
-            }
-            // there are remain datas after this message
-            cache.insert(cache.end(), msg.data_, msg.data_ + data_length);
-        }
-    }
+    return updating_recv([&] {
+        return std::forward_as_tuple(q_arr, q_arr.size());
+    });
+}
+
+buff_t recv(handle_t h) {
+    return recv(&h, 1);
 }
 
 } // namespace ipc
+
+#include "route.hpp"
+#include "channel.hpp"

src/route.hpp

@@ -1,6 +1,10 @@
 #include "ipc.h"
 #include "def.h"
 
+////////////////////////////////////////////////////////////////
+/// class route implementation
+////////////////////////////////////////////////////////////////
+
 namespace ipc {
 
 class route::route_ : public pimpl<route_> {