Change default README from Japanese to English

At first time, maruyama-san created Japanese document.
M-amir097 contributed English document.
This patch change default README to English version.

Signed-off-by: Naoto Yamaguchi <i33399_yamaguchi@aisin-aw.co.jp>

1 files changed, 452 insertions, 0 deletions

diff --git a/README.md b/README.md
new file mode 100644
index 0000000..0c68351
--- /dev/null
+++ b/README.md
@@ -0,0 +1,452 @@
+# IPC Diversion Section
+
+## Overview
+
+* It is a general-purpose implementation of Inter-processing communication between the Server and Client (IPC section).
+* It consists mainly of the following:
+  * IPC library implementation source: src, include
+  * IPC unit test program: ipc_unit_test
+
+# Building Method
+
+* Building by following steps:
+  ```bash
+  $ mkdir build
+  $ cd build
+  $ cmake ..
+  $ make
+  ```
+  * The above commands can be executed with the following script:
+    ```bash
+    $ ./buildtest.sh
+    ```
+
+The installation described next will be installed on the host PC (/usr/local/). To change the installation destination, change the option passed to cmake.
+
+```
+Example 
+$ cmake -DCMAKE_INSTALL_PREFIX=./install ..
+```
+
+# Installing Method
+
+  ```bash
+  $ cd build
+  $ sudo make install
+  ```
+
+When succeeded, the following log will be output. 
+
+```
+[100%] Built target ipc
+Install the project...
+-- Install configuration: ""
+-- Installing: /usr/local/lib/pkgconfig/ipc.pc
+-- Installing: /usr/local/lib/libipc.so.1.0.0
+-- Installing: /usr/local/lib/libipc.so.1
+-- Installing: /usr/local/lib/libipc.so
+-- Installing: /usr/local/include/ipc.h
+-- Installing: /usr/local/include/ipc_protocol.h
+```
+
+# Building Product 
+
+* At last, Building will generate the following:
+  * \<installdir\>/include/
+(External Public header files)
+    ```bash
+    ipc.h
+    ipc_protocol.h
+    ```
+  * \<installdir\>/lib/
+(Shared library files) 
+    ```bash
+    libipc.so   ( Symbolic link ) 
+    libipc.so.1 ( Symbolic link )
+    libipc.so.1.0.0
+    ```
+  * build/ipc_unit_test/
+(Test program executable file)
+    ```bash
+    ipc_unit_test_client
+    ipc_unit_test_server
+    ```
+<br>
+
+# How to use
+
+* This library contains functions for Server and Client; Each has different usage.
+
+## Common of Server/Client 
+
+* The user needs to link with the following libraries.
+  * `libipc.so`
+* User includes the library as following.
+  * #include <ipc.h>
+    * ipc_protocol.h description is not required; it described later within ipc.h (include <ipc.h>).
+* The header files are used as follows.
+  * ipc.h
+    * Declare a list of available API functions.
+  * ipc_protocol.h
+    * Define IPC usage types and data structures for each usage.
+* In libraries, Server and Client communicate using Unix Domain Socket.
+  * Generate different communication files for each usage type. 
+  * By default, a communication file is generated in the execution hierarchy of the Server.
+  * For changing the location where generating the communication files, set the environment variable "IPC_DOMAIN_PATH" 
+  ```
+  Example)
+  $ export IPC_DOMAIN_PATH="/tmp"
+    →Unix Domain Socket communication files will be generated under /tmp.
+  ```
+
+## For IC-Service
+
+* Using this library for IC-Service, use the following values and structures (see ipc_protocol.h). 
+  * UsageType：IPC_USAGE_TYPE_IC_SERVICE
+  * Sending data structure：IPC_DATA_IC_SERVICE_S
+  * Changing type callback notification (enum)：IPC_KIND_IC_SERVICE_E
+  * Unix Domain Socket communication File name：IpcIcService
+* For IC-Service, the Cluster API library (libcluster_api.so) is the IPC Client. 
+  * The API for Client is called from libcluster_api.so (described later)
+
+##  Server API
+
+* Server applied libipc.so can use the following APIs:
+  * ipcServerStart(IPC_USAGE_TYPE_E usageType);
+    * Starting the IPC Server for the specified _usageType_.
+  * ipcSendMessage(IPC_USAGE_TYPE_E usageType, const void* pData, signed int size);
+    * Sending data to the IPC Client for the specified _usageType_. 
+    * Specifying address and size of the sending data by pData and size arguments. 
+    * Sending data is stored in the Data Pool prepared on the IPC Client side.
+  * ipcServerStop(IPC_USAGE_TYPE_E usageType);
+    * Terminate the IPC Server for the specified usageType.
+
+## Client API
+
+* The Client applied libipc.so can use the following APIs:
+  * ipcClientStart(IPC_USAGE_TYPE_E usageType);
+    * Starting the IPC Client for the specified usageType.
+    * Connecting with IPC Server for the same usageType.
+  * ipcReadDataPool(IPC_USAGE_TYPE_E usageType, void* pData, signed int* pSize);
+    * Reading all data in the Data Pool for the specified usageType.
+    * The address where storing the read data is specified in pData. Moreover, the size of storing data is specified in pSize.
+    * The contents of the Data Pool output to pData, and the actual read size output to pSize.
+  * ipcRegisterCallback(IPC_USAGE_TYPE_E usageType, IPC_CHANGE_NOTIFY_CB changeNotifyCb);
+    * When receiving data from the IPC Server, register the callback function for the specified usageType, which receiving notification of which data changed to what.
+  * ipcClientStop(IPC_USAGE_TYPE_E usageType);
+    * Terminate the IPC Client for the specified usageType.
+
+# Unit test executing method
+
+* Limitations
+  * Currently 2020/12/25, this test program connects Server and Client for IC-Service.  
+  * The Unix domain socket communication files are generated under /tmp/ with the file name ipcIcService.
+
+* Since Inter processing communication takes place between ipc_unit_test_server and ipc_unit_test_client, so start each one in a separate terminal.
+  Testing example as bellow (Manually operated): 
+
+  1. **Starting Server and then starting Client**
+      ```bash
+      (Terminal 1)
+      $ ./ipc_unit_test_server
+      command (h=help, q=quit):
+      ```
+      ```bash
+      (Terminal 2)
+      $ ./ipc_unit_test_client
+      command (h=help, q=quit):
+      ```  
+      At this point, the Server and Client connection for IC-Service is completed.
+      (Executing ipcServerStart () and ipcClientStart ())
+
+  2. **Editing and Sending Server data**
+      ```bash
+      (Terminal 1)
+      command (h=help, q=quit):w ←★input w 
+      write command (h=help q=goto main menu):2 1 ←★input 2 1
+      write command (h=help q=goto main menu):70 50 ←★input 70 50
+      write command (h=help q=goto main menu):l ←★input 1
+      ★Sending data list is displayed, the result of input contents as below. 
+        2: brake(4) = 1 ←★write command 2 1 result
+        70: oTempUnitVal(4) = 50 ←★write command 70 50 result
+      write command (h=help q=goto main menu):q ←★input q
+      command (h=help, q=quit):s ←★input s (Executing ipcSendMessage())
+      ipcSendMessage return:0
+      command (h=help, q=quit):
+      ```
+      On the Client side, The callback function should be responding.
+      ```bash
+      (Terminal 2)
+      command (h=help, q=quit):Enter changeNotifyCb ←★callback
+      kind = 2, size = 4, data=1 ←★Notification of brake value changed to 1 
+      Leave changeNotifyCb
+      ```
+      ★oFor TempUnitVal change as an IC-Service, there is no callback since it is not monitored.
+
+  3. **Check Client side receiving.**  
+      ```bash
+      (Terminal 2)
+      command (h=help, q=quit):r ←★input r
+      ★Sending data list is displayed, Sending data contained as bellow. 
+        2: brake(4) = 1
+       70: oTempUnitVal(4) = 50
+      ```
+
+  4. **Exit Client then Server.** 
+      ```bash
+      (Terminal 2)
+      command (h=help, q=quit):q
+      bye...
+      $
+      ```
+      ```bash
+      (Terminal 1)
+      command (h=help, q=quit):q
+      bye...
+      $
+      ```
+
+# Adding/Changing IPC usage type method
+ 
+* First, the implementation only for IC-Service, but configured to add data for other services easily.
+* Information for each usage type is managed in the following files:
+  * include/ipc_protocol.h (External Public header)
+  * src/ipc_usage_info_table.c (IPC Internal Source)
+* Adding information for new service or changing information for existed service only by two files above.
+  * No changes are required other than .c or .h files in ipc.
+  * However, Regarding the application and test program used IPC, It is necessary to take measures according to the adding/changing of the ipc_protocol.h definition.
+* Ideally, code can be generated automatically using tools and else. We do not consider that implementation this time.
+
+## Sample code for adding/changing the usage type (Sample code difference)
+
+First, the sample code for adding/changing two files as follow.
+
+### Example 1: When adding a new usage type
+
+The following example shows differences when adding the temporary usage type NEW_SERVICE.
+(Parameters influenced when adding new usage type within the IPC)
+
+```patch
+diff --git a/include/ipc_protocol.h b/include/ipc_protocol.h
+index c0ad861..2bc1115 100644
+--- a/include/ipc_protocol.h
++++ b/include/ipc_protocol.h
+@@ -6,6 +6,7 @@
+ typedef enum {
+     IPC_USAGE_TYPE_IC_SERVICE = 0,
+     IPC_USAGE_TYPE_FOR_TEST,
++    IPC_USAGE_TYPE_NEW_SERVICE, // Adding usage type
+     IPC_USAGE_TYPE_MAX
+ } IPC_USAGE_TYPE_E;
+
+@@ -145,4 +146,17 @@ typedef struct {
+     signed int test;
+ } IPC_DATA_FOR_TEST_S;
+
++// for IPC_USAGE_TYPE_NEW_SERVICE
++typedef enum { // Preparing only the type which we want to monitor/notify data change
++    IPC_KIND_NS_PARAM1 = 0,
++    IPC_KIND_NS_PARAM2
++} IPC_KIND_NEW_SERVICE_E;
++
++typedef struct { // This part for sending and receiving all data 
++    int param1;
++    int param2;
++    int param3;
++    int param4;
++} IPC_DATA_NEW_SERVICE_S;
++
+ #endif // IPC_PROTOCOL_H
+diff --git a/src/ipc_usage_info_table.c b/src/ipc_usage_info_table.c
+index 976cc73..51264c6 100644
+--- a/src/ipc_usage_info_table.c
++++ b/src/ipc_usage_info_table.c
+@@ -51,16 +51,24 @@ static IPC_CHECK_CHANGE_INFO_S g_ipcCheckChangeForTest[] = {
+     DEFINE_OFFSET_SIZE(IPC_DATA_FOR_TEST_S, test, IPC_KIND_TEST_TEST)
+ };
+
++//   for IPC_USAGE_TYPE_FOR_TEST
++static IPC_CHECK_CHANGE_INFO_S g_ipcCheckChangeNewService[] = { // Describing only the type which we want to monitor/notify data change
++    DEFINE_OFFSET_SIZE(IPC_DATA_NEW_SERVICE_S, param1, IPC_KIND_NS_PARAM1),
++    DEFINE_OFFSET_SIZE(IPC_DATA_NEW_SERVICE_S, param2, IPC_KIND_NS_PARAM2)
++}; //This example not monitoring/notifying changes of param3, param4 data
++
+ // == usage info table ==
+ //   index of [] is IPC_USAGE_TYPE_E
+ IPC_DOMAIN_INFO_S g_ipcDomainInfoList[] =
+ {
+     {sizeof(IPC_DATA_IC_SERVICE_S), "ipcIcService"},
+-    {sizeof(IPC_DATA_FOR_TEST_S), "ipcForTest"}
++    {sizeof(IPC_DATA_FOR_TEST_S), "ipcForTest"},
++    {sizeof(IPC_DATA_NEW_SERVICE_S), "ipcNewService"} // add sending/receiving size information for new Service 
+ };
+
+ IPC_CHECK_CHANGE_INFO_TABLE_S g_ipcCheckChangeInfoTbl[] = {
+     DEFINE_CHANGE_INFO_TABLE(g_ipcCheckChangeIcService),
+-    DEFINE_CHANGE_INFO_TABLE(g_ipcCheckChangeForTest)
++    DEFINE_CHANGE_INFO_TABLE(g_ipcCheckChangeForTest),
++    DEFINE_CHANGE_INFO_TABLE(g_ipcCheckChangeNewService) // Registering data change monitoring table for new Service
+ };
+
+```
+
+### Example 2: Deleting part of the existing usage type data
+
+The following example shows differences when deleting the member variable brake from usage sending/receiving data of existing IC-Service.
+(Parameters influenced when a member variable is deleted within the IPC) 
+
+```patch
+diff --git a/include/ipc_protocol.h b/include/ipc_protocol.h
+index c0ad861..7fed8bf 100644
+--- a/include/ipc_protocol.h
++++ b/include/ipc_protocol.h
+@@ -13,7 +13,6 @@ typedef enum {
+ typedef enum {
+     IPC_KIND_ICS_TURN_R = 0,
+     IPC_KIND_ICS_TURN_L,
+-    IPC_KIND_ICS_BRAKE,
+     IPC_KIND_ICS_SEATBELT,
+     IPC_KIND_ICS_HIGHBEAM,
+     IPC_KIND_ICS_DOOR,
+@@ -51,7 +50,6 @@ typedef struct {
+     // Telltale
+     signed int turnR;
+     signed int turnL;
+-    signed int brake;
+     signed int seatbelt;
+     signed int frontRightSeatbelt;
+     signed int frontCenterSeatbelt;
+diff --git a/src/ipc_usage_info_table.c b/src/ipc_usage_info_table.c
+index 976cc73..40ac8df 100644
+--- a/src/ipc_usage_info_table.c
++++ b/src/ipc_usage_info_table.c
+@@ -12,7 +12,6 @@
+ static IPC_CHECK_CHANGE_INFO_S g_ipcCheckChangeIcService[] = {
+     DEFINE_OFFSET_SIZE(IPC_DATA_IC_SERVICE_S, turnR, IPC_KIND_ICS_TURN_R),
+     DEFINE_OFFSET_SIZE(IPC_DATA_IC_SERVICE_S, turnL, IPC_KIND_ICS_TURN_L),
+-    DEFINE_OFFSET_SIZE(IPC_DATA_IC_SERVICE_S, brake, IPC_KIND_ICS_BRAKE),
+     DEFINE_OFFSET_SIZE(IPC_DATA_IC_SERVICE_S, seatbelt, IPC_KIND_ICS_SEATBELT),
+     DEFINE_OFFSET_SIZE(IPC_DATA_IC_SERVICE_S, highbeam, IPC_KIND_ICS_HIGHBEAM),
+     DEFINE_OFFSET_SIZE(IPC_DATA_IC_SERVICE_S, door, IPC_KIND_ICS_DOOR),
+```
+
+## Common items regarding new addition of usage type
+
+* Adding some new enumerations/structures, with addition to existing enumeration/structure. There are no restrictions on the names.
+
+## Adding Information to include/ipc_protocol.h
+* For one usage type, adding the following three items of information.
+  * Add usage type name.
+  * For new usage, Define enumeration for the change notification type.
+  * For new usage, Define sending/receiving data structure.
+* Adding usage type name
+  * Sample code of this part will be as follow:
+    ```patch
+     typedef enum {
+         IPC_USAGE_TYPE_IC_SERVICE = 0,
+         IPC_USAGE_TYPE_FOR_TEST,
+    +    IPC_USAGE_TYPE_NEW_SERVICE, // Adding usage type
+         IPC_USAGE_TYPE_MAX
+     } IPC_USAGE_TYPE_E;
+    ```
+  * Adding a member for the usage type in enum IPC_USAGE_TYPE_E.
+  * Make sure to add it just before IPC_USAGE_TYPE_MAX (Avoiding effect on existing definitions)
+  * The value defined here is used to specify the argument usageType such as ipcServerStart() defined in ipc.h.
+* For new usage, Define enumeration for the change notification type.
+  * Sample code of this part will be as follow:
+    ```patch
+    +typedef enum { // Preparing only the type which we want to monitor data change
+    +    IPC_KIND_NS_PARAM1 = 0,
+    +    IPC_KIND_NS_PARAM2
+    +} IPC_KIND_NEW_SERVICE_E;
+    ```
+  * Adding an enumeration for the data change notification type. Related to the sending/receiving data structures will describe next.
+  * This value is used to specify the third argument kind of callback function registered by ipcRegisterCallback().
+  * There are no restrictions for naming enumeration and member.
+* For new usage, Define sending/receiving data structure. 
+  * Sample code of this part will be as follow:
+    ```patch
+    +typedef struct { // This part for sending and receiving all data
+    +    int param1;
+    +    int param2;
+    +    int param3;
+    +    int param4;
+    +} IPC_DATA_NEW_SERVICE_S;
+    ```
+  * For new usage, adding send/receive data structures.
+  * The IPC Server will send all the data in the defined structure to the IPC Client.
+
+## Regarding adding src/ipc_usage_info_table.c
+* For one usage type, adding the following three items of information.
+  * Add a type mapping table for data change notification.
+  * Add communication domain information (Communication size and file name).
+  * Add mapping table for a relationship between usage and change type.
+* Add a type mapping table for data change notification.
+  * Sample code of this part will be as follow:
+    ```
+    +//   for IPC_USAGE_TYPE_FOR_TEST
+    +static IPC_CHECK_CHANGE_INFO_S g_ipcCheckChangeNewService[] = { // Preparing only the type which we want to monitor data change
+    +    DEFINE_OFFSET_SIZE(IPC_DATA_NEW_SERVICE_S, param1, IPC_KIND_NS_PARAM1),
+    +    DEFINE_OFFSET_SIZE(IPC_DATA_NEW_SERVICE_S, param2, IPC_KIND_NS_PARAM2)
+    +}; // This example not monitoring/notifying changes of param3, param4 data
+    ```
+  * For new usage, add a structure array of IPC_CHECK_CHANGE_INFO_S.
+  * Describing a table that maps the definition of change notification type enumeration (defined in ipc_protocol.h) with the data structure members.
+  * This table is used for Callback notification of the last receiving data type change when the IPC Client received data from the IPC Server. 
+  * In structure array, describing multiple macros which defining matching as shown below.
+    ```c
+    DEFINE_OFFSET_SIZE(<Data structure name>, <Structure member name>, Change notification enumeration member name),
+    ```
+  * In the case of the above sample code, g_ipcCheckChangeNewService[] will be as follows. 
+    * If the value of param1 is different from the value of the previous receiving, the callback change type IPC_KIND_NS_PARAM1 is notified to the IPC Client.
+    * If the value of param2 is different from the value of the previous receiving, the callback change type IPC_KIND_NS_PARAM2 is notified to the IPC Client.
+    * For param3 and param4 are not described, the callback does not notify even if the value of the previous receiving is different.
+
+* Add communication domain information (Communication size and file name).
+  * Sample code of this part will be as follow:
+    ```patch
+     IPC_DOMAIN_INFO_S g_ipcDomainInfoList[] =
+     {
+         {sizeof(IPC_DATA_IC_SERVICE_S), "ipcIcService"},
+    -    {sizeof(IPC_DATA_FOR_TEST_S), "ipcForTest"}
+    +    {sizeof(IPC_DATA_FOR_TEST_S), "ipcForTest"},
+    +    {sizeof(IPC_DATA_NEW_SERVICE_S), "ipcNewService"} //add sending/receiving size information for new Service 
+     };
+    ```
+  * In structure array g_ipcDomainInfoList[], adding the domain information for new usage.
+  * This addition determines the sending/receiving data size used for the newly added usage type and Domain file name used for Unix Domain Socket communication. 
+  * It is necessary to match the definition order of the enum IPC_USAGE_TYPE_E of ipc_protocol.h, so ensure adding it at the end.
+  * Add communication data size structure and the domain filename information to the end of g_ipcDomainInfoList[], as follows:
+    ```c
+    {sizeof(<communication data structure name>), "domain file name"},
+    ```
+* Add mapping table for a relationship between usage and change type.  
+  * Sample code of this part will be as follow:
+    ```patch
+     IPC_CHECK_CHANGE_INFO_TABLE_S g_ipcCheckChangeInfoTbl[] = {i
+         DEFINE_CHANGE_INFO_TABLE(g_ipcCheckChangeIcService),
+    -    DEFINE_CHANGE_INFO_TABLE(g_ipcCheckChangeForTest)
+    +    DEFINE_CHANGE_INFO_TABLE(g_ipcCheckChangeForTest),
+    +    DEFINE_CHANGE_INFO_TABLE(g_ipcCheckChangeNewService) // Registering data change monitoring table for new service
+     };
+    ```
+  * In structure array g_ipcCheckChangeInfoTbl[], adding information about the mapping table for a relationship between new usage and change notification type.
+  * It is necessary to match the definition order of the enum IPC_USAGE_TYPE_E of ipc_protocol.h, so ensure adding it at the end.
+  * Describing the above-mentioned "change notification type mapping table structure" in the following macro, then add it to the end of g_ipcCheckChangeInfoTbl[].
+    ```c
+    DEFINE_CHANGE_INFO_TABLE(<change notification type mapping table structure name>), 
+    ```
+
+## Changing of sending data for existing usage
+* When deleting or renaming a member variable in an existing sending data structure in ipc_protocol.h
+  * Trying to build each ipc part and application that uses ipc for the service, then fix the part that causing the Compile error. 
+
+* When adding a member variable in an existing sending data structure in ipc_protocol.h
+  * Refer to [Adding/Changing IPC usage type method](#adding-changing-ipc-usage-type-method), add it to include/ipc_protocol.h and src/ipc_usage_info_table.c.
+
+## Supplement
+* In src/ipc_usage_info_table.c, the information is described in the DEFINE_OFFSET_SIZE() macro, which using offsetof() and sizeof() to get the offset and size of member variables from the head of the related structure.
+  * In order to make it easier to add usage types, the IPC process does not directly specify variable names in data structures.
+  * For each usage, by preparing an offset table of the data structure, it becomes possible to know what variables are in which byte of the sending data.
+    * This structure makes it possible to check data change without directly specifying the member variable name inside the IPC process.
+  * Adding the usage type according to [Adding/Changing IPC usage type method](#adding-changing-ipc-usage-type-method), the IPC inter processing can process new usage.