cli socket path bug fix

[moshehe]

Bug in the CLI socket

The OpenBTS-UMTSCLI app is unable to locate the socket used for sending commands to OpenBTS-UMTS app

Steps to Reproduce the Bug

1. Run the OpenBTS-UMTS Application:

   • Launch the OpenBTS-UMTS application by running: ./OpenBTS-UMTS.

2. Run the OpenBTS-UMTSCLI Application:

   • Launch the OpenBTS-UMTS application by running: ./OpenBTS-UMTSCLI.

3. Send command from the CLI app:

   • In the OpenBTS-UMTSCLI app run a command e.g rawconfig.

4. Expected Behavior:

   • The command is expected to be sent to the OpenBTS-UMTS application, and the corresponding response should be displayed.

5. Actual Behavior:

   • Instead, the output is:

    sending datagram: No such file or directory
    Is the remote application running?
   

Root Cause

The reason for this problem is the way of saving the path string of the CLI socket.
In apps/OpenBTS-UMTS.cpp line 263:

const char* sockpath = gConfig.getStr("CLI.SocketPath").c_str();

The c_str function returns a pointer that points to the internal array currently used by the string object. However, as we are only using a pointer to the object without retaining the string object itself, the pointer refers to an array containing garbage values instead of the correct path (which is /var/run/OpenBTS-UMTS-command by default). Consequently, rather than opening the socket in the intended path, the code attempts to open the socket file with a nonsensical name in the current directory.

Fix

To address this bug, I introduced a new variable to hold the string object, and then added another variable of type char* to reference the array within the string object. With these changes, the socket now opens correctly in the expected path, allowing the successful transmission of commands from OpenBTS-UMTSCLI app.