Cleaned up the mess from #12610:

* Command line options need to be documented.
* Don't assume C strings returned as option values remain valid
  indefinitely.
* Fixed wording for option description.

Author: cuavas

docs/source/commandline/commandline-all.rst

@@ -3677,8 +3677,9 @@ Debugging Options
         Acts as a remote debugging server for the GNU debugger (GDB).  Only a
         small subset of the CPUs emulated by MAME are supported.  Use the
         :ref:`debugger_port <mame-commandline-debuggerport>` option to set the
-        listening port on the loopback interface.  Supported on all platforms
-        with TCP socket support.
+        listening port and the
+        :ref:`debugger_host <mame-commandline-debuggerhost>` option to set the
+        address to bind to.  Supported on all platforms with TCP socket support.
 
     Example:
         .. code-block:: bash
@@ -3732,11 +3733,26 @@ Debugging Options
 
             mame ibm_5150 -watchdog 30
 
+.. _mame-commandline-debuggerhost:
+
+**-debugger_host** *<address>*
+
+    Set the IP address to listen on to accept GDB connections when using the
+    GDB stub debugger module (see the
+    :ref:`debugger <mame-commandline-debugger>` option).
+
+    The default is ``localhost``.
+
+    Example:
+        .. code-block:: bash
+
+            mame rfjet -debug -debugger gdbstub -debugger_host 0.0.0.0
+
 .. _mame-commandline-debuggerport:
 
 **-debugger_port** *<port>*
 
-    Set the TCP port number to listen on for GDB connections when using the GDB
+    Set the TCP port number to accept GDB connections on when using the GDB
     stub debugger module (see the :ref:`debugger <mame-commandline-debugger>`
     option).
 

docs/source/commandline/commandline-index.rst

@@ -298,6 +298,7 @@ Core Debugging Options
 | :ref:`debugscript <mame-commandline-debugscript>`
 | :ref:`[no]update_in_pause <mame-commandline-updateinpause>`
 | :ref:`watchdog <mame-commandline-watchdog>`
+| :ref:`debugger_host <mame-commandline-debuggerhost>`
 | :ref:`debugger_port <mame-commandline-debuggerport>`
 | :ref:`debugger_font <mame-commandline-debuggerfont>`
 | :ref:`debugger_font_size <mame-commandline-debuggerfontsize>`

src/osd/modules/debugger/debuggdbstub.cpp

@@ -496,8 +496,8 @@ static const std::map<std::string, const gdb_register_map &> gdb_register_maps =
 class debug_gdbstub : public osd_module, public debug_module
 {
 public:
-	debug_gdbstub()
-	: osd_module(OSD_DEBUG_PROVIDER, "gdbstub"), debug_module(),
+	debug_gdbstub() :
+		osd_module(OSD_DEBUG_PROVIDER, "gdbstub"), debug_module(),
 		m_readbuf_state(PACKET_START),
 		m_machine(nullptr),
 		m_maincpu(nullptr),
@@ -506,7 +506,7 @@ class debug_gdbstub : public osd_module, public debug_module
 		m_address_space(nullptr),
 		m_debugger_cpu(nullptr),
 		m_debugger_console(nullptr),
-		m_debugger_host(nullptr),
+		m_debugger_host(),
 		m_debugger_port(0),
 		m_socket(OPEN_FLAG_WRITE | OPEN_FLAG_CREATE),
 		m_is_be(false),
@@ -601,7 +601,7 @@ class debug_gdbstub : public osd_module, public debug_module
 	address_space *m_address_space;
 	debugger_cpu *m_debugger_cpu;
 	debugger_console *m_debugger_console;
-	const char *m_debugger_host;
+	std::string m_debugger_host;
 	int m_debugger_port;
 	emu_file m_socket;
 	bool m_is_be;
@@ -795,8 +795,8 @@ void debug_gdbstub::wait_for_debugger(device_t &device, bool firststop)
 		std::string socket_name = string_format("socket.%s:%d", m_debugger_host, m_debugger_port);
 		std::error_condition const filerr = m_socket.open(socket_name);
 		if ( filerr )
-			fatalerror("gdbstub: failed to start listening on host %s port %d\n", m_debugger_host, m_debugger_port);
-		osd_printf_info("gdbstub: listening on host %s port %d\n", m_debugger_host, m_debugger_port);
+			fatalerror("gdbstub: failed to start listening on address %s port %d\n", m_debugger_host, m_debugger_port);
+		osd_printf_info("gdbstub: listening on address %s port %d\n", m_debugger_host, m_debugger_port);
 
 		m_initialized = true;
 	}

src/osd/modules/lib/osdobj_common.cpp

@@ -58,7 +58,7 @@ const options_entry osd_options::s_option_entries[] =
 
 	{ nullptr,                                   nullptr,          core_options::option_type::HEADER,    "OSD DEBUGGING OPTIONS" },
 	{ OSDOPTION_DEBUGGER,                        OSDOPTVAL_AUTO,   core_options::option_type::STRING,    "debugger used: " },
-	{ OSDOPTION_DEBUGGER_HOST,                   "localhost",      core_options::option_type::STRING,    "host to use for gdbstub debugger" },
+	{ OSDOPTION_DEBUGGER_HOST,                   "localhost",      core_options::option_type::STRING,    "address to bind to for gdbstub debugger" },
 	{ OSDOPTION_DEBUGGER_PORT,                   "23946",          core_options::option_type::INTEGER,   "port to use for gdbstub debugger" },
 	{ OSDOPTION_DEBUGGER_FONT ";dfont",          OSDOPTVAL_AUTO,   core_options::option_type::STRING,    "font to use for debugger views" },
 	{ OSDOPTION_DEBUGGER_FONT_SIZE ";dfontsize", "0",              core_options::option_type::FLOAT,     "font size to use for debugger views" },