From b6c25760cfecd921e2293522119fb5005152ac4a Mon Sep 17 00:00:00 2001
From: mutouyun <orz@orzz.org>
Date: Sat, 23 Sep 2023 14:19:12 +0800
Subject: [PATCH] Supplement similar demo under linux.

---
 CMakeLists.txt                            |  3 ++
 demo/linux_service/client/CMakeLists.txt  |  8 ++++++
 demo/linux_service/client/main.cpp        | 28 ++++++++++++++++++
 demo/linux_service/service/CMakeLists.txt |  8 ++++++
 demo/linux_service/service/main.cpp       | 35 +++++++++++++++++++++++
 src/libipc/platform/posix/shm_posix.cpp   |  4 ++-
 6 files changed, 85 insertions(+), 1 deletion(-)
 create mode 100644 demo/linux_service/client/CMakeLists.txt
 create mode 100644 demo/linux_service/client/main.cpp
 create mode 100644 demo/linux_service/service/CMakeLists.txt
 create mode 100644 demo/linux_service/service/main.cpp

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 12cebd4..7e07dd3 100755
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -62,6 +62,9 @@ if (LIBIPC_BUILD_DEMOS)
     if (MSVC)
         add_subdirectory(demo/win_service/service)
         add_subdirectory(demo/win_service/client)
+    else()
+        add_subdirectory(demo/linux_service/service)
+        add_subdirectory(demo/linux_service/client)
     endif()
 endif()
 
diff --git a/demo/linux_service/client/CMakeLists.txt b/demo/linux_service/client/CMakeLists.txt
new file mode 100644
index 0000000..b7d8392
--- /dev/null
+++ b/demo/linux_service/client/CMakeLists.txt
@@ -0,0 +1,8 @@
+project(linux_client)
+
+file(GLOB SRC_FILES ./*.cpp)
+file(GLOB HEAD_FILES ./*.h)
+
+add_executable(${PROJECT_NAME} ${SRC_FILES} ${HEAD_FILES})
+
+target_link_libraries(${PROJECT_NAME} ipc)
diff --git a/demo/linux_service/client/main.cpp b/demo/linux_service/client/main.cpp
new file mode 100644
index 0000000..9839be9
--- /dev/null
+++ b/demo/linux_service/client/main.cpp
@@ -0,0 +1,28 @@
+/// \brief To create a basic command line program.
+
+#include <stdio.h>
+#include <thread>
+#include <chrono>
+
+#include "libipc/ipc.h"
+
+int main(int argc, char *argv[]) {
+    printf("My Sample Client: Entry\n");
+    ipc::channel ipc_r{"service ipc r", ipc::receiver};
+    ipc::channel ipc_w{"service ipc w", ipc::sender};
+    while (1) {
+        auto msg = ipc_r.recv();
+        if (msg.empty()) {
+            printf("My Sample Client: message recv error\n");
+            return -1;
+        }
+        printf("My Sample Client: message recv: [%s]\n", (char const *)msg.data());
+        while (!ipc_w.send("Copy.")) {
+            printf("My Sample Client: message send error\n");
+            std::this_thread::sleep_for(std::chrono::seconds(1));
+        }
+        printf("My Sample Client: message send [Copy]\n");
+    }
+    printf("My Sample Client: Exit\n");
+    return 0;
+}
diff --git a/demo/linux_service/service/CMakeLists.txt b/demo/linux_service/service/CMakeLists.txt
new file mode 100644
index 0000000..a877337
--- /dev/null
+++ b/demo/linux_service/service/CMakeLists.txt
@@ -0,0 +1,8 @@
+project(linux_service)
+
+file(GLOB SRC_FILES ./*.cpp)
+file(GLOB HEAD_FILES ./*.h)
+
+add_executable(${PROJECT_NAME} ${SRC_FILES} ${HEAD_FILES})
+
+target_link_libraries(${PROJECT_NAME} ipc)
diff --git a/demo/linux_service/service/main.cpp b/demo/linux_service/service/main.cpp
new file mode 100644
index 0000000..ec2f4a9
--- /dev/null
+++ b/demo/linux_service/service/main.cpp
@@ -0,0 +1,35 @@
+/// \brief To create a basic Windows Service in C++.
+/// \see https://www.codeproject.com/Articles/499465/Simple-Windows-Service-in-Cplusplus
+
+#include <stdio.h>
+#include <string>
+#include <thread>
+#include <chrono>
+
+#include "libipc/ipc.h"
+
+int main(int argc, char *argv[]) {
+    printf("My Sample Service: Main: Entry\n");
+
+    ipc::channel ipc_r{"service ipc r", ipc::sender};
+    ipc::channel ipc_w{"service ipc w", ipc::receiver};
+
+    while (1) {
+        if (!ipc_r.send("Hello, World!")) {
+            printf("My Sample Service: send failed.\n");
+        }
+        else {
+            printf("My Sample Service: send [Hello, World!]\n");
+            auto msg = ipc_w.recv(1000);
+            if (msg.empty()) {
+                printf("My Sample Service: recv error\n");
+            } else {
+                printf("%s\n", (std::string{"My Sample Service: recv ["} + msg.get<char const *>() + "]").c_str());
+            }
+        }
+        std::this_thread::sleep_for(std::chrono::seconds(3));
+    }
+
+    printf("My Sample Service: Main: Exit\n");
+    return 0;
+}
diff --git a/src/libipc/platform/posix/shm_posix.cpp b/src/libipc/platform/posix/shm_posix.cpp
index 7f70b07..b0bfdef 100644
--- a/src/libipc/platform/posix/shm_posix.cpp
+++ b/src/libipc/platform/posix/shm_posix.cpp
@@ -49,7 +49,9 @@ id_t acquire(char const * name, std::size_t size, unsigned mode) {
         ipc::error("fail acquire: name is empty\n");
         return nullptr;
     }
-    ipc::string op_name = ipc::string{"__IPC_SHM__"} + name;
+    // For portable use, a shared memory object should be identified by name of the form /somename.
+    // see: https://man7.org/linux/man-pages/man3/shm_open.3.html
+    ipc::string op_name = ipc::string{"/__IPC_SHM__"} + name;
     // Open the object for read-write access.
     int flag = O_RDWR;
     switch (mode) {