Command line arguments handling overhaul

- login_server, char_server, map_server as well as the tools (mapcache)
  now have a common command line arguments handling mechanism.
- All of them now accept `--help` (`-h`), `--version` (`-v`) and
  `--load-plugin`.
- login_server now accepts `--login-config` and `--lan-config` instead
  of relying on positional arguments to override those files. The old
  syntax will no longer work, please update your custom startup scripts.
- char_server now accepts `--char-config`, `--inter-config`,
  `--lan-config` instead of relying on positional arguments. The old
  syntax will no longer work, please update your custom startup scripts.
- mapcache now accepts `--grf-list`, `--map-list`, `--map-cache`,
  `--rebuild` in place of, respectively, `-grf`, `-list`, `-cache`,
  `-rebuild`.
- A new macro `CMDLINEARG()` is provided, to help defining new command
  line argument handlers (i.e. in plugins). the `addArg()` call is still
  required, but its syntax has changed. The `help` argument is now of type
  `const char *` rather than a function pointer, and it is supposed to
  contain the message to show in the `--help` screen. Pass `NULL` if no
  help message is desired.

Signed-off-by: Haru <haru@dotalux.com>

1 files changed, 198 insertions, 9 deletions

diff --git a/src/common/core.c b/src/common/core.c
index e1bb9ed0b..6ad971c86 100644
--- a/src/common/core.c
+++ b/src/common/core.c
@@ -178,6 +178,7 @@ void core_defaults(void) {
 	console_defaults();
 	strlib_defaults();
 	malloc_defaults();
+	cmdline_defaults();
 #ifndef MINICORE
 	libconfig_defaults();
 	sql_defaults();
@@ -186,6 +187,196 @@ void core_defaults(void) {
 	socket_defaults();
 #endif
 }
+/**
+ * Returns the source (core or plugin name) for the given command-line argument
+ */
+const char *cmdline_arg_source(struct CmdlineArgData *arg) {
+#ifdef MINICORE
+	return "core";
+#else // !MINICORE
+	return HPM->pid2name(arg->pluginID);
+#endif // MINICORE
+}
+/**
+ * Defines a command line argument.
+ *
+ * @param pluginID  the source plugin ID (use HPM_PID_CORE if loading from the core).
+ * @param name      the command line argument name, including the leading '--'.
+ * @param shortname an optional short form (single-character, it will be prefixed with '-'). Use '\0' to skip.
+ * @param func      the triggered function.
+ * @param help      the help string to be displayed by '--help', if any.
+ * @param options   options associated to the command-line argument. @see enum cmdline_options.
+ * @return the success status.
+ */
+bool cmdline_arg_add(unsigned int pluginID, const char *name, char shortname, CmdlineExecFunc func, const char *help, unsigned int options) {
+	struct CmdlineArgData *data = NULL;
+	
+	RECREATE(cmdline->args_data, struct CmdlineArgData, ++cmdline->args_data_count);
+	data = &cmdline->args_data[cmdline->args_data_count-1];
+	data->pluginID = pluginID;
+	data->name = aStrdup(name);
+	data->shortname = shortname;
+	data->func = func;
+	data->help = aStrdup(help);
+	data->options = options;
+
+	return true;
+}
+/**
+ * Help screen to be displayed by '--help'.
+ */
+static CMDLINEARG(help)
+{
+	int i;
+	ShowInfo("Usage: %s [options]\n", SERVER_NAME);
+	ShowInfo("\n");
+	ShowInfo("Options:\n");
+	
+	for (i = 0; i < cmdline->args_data_count; i++) {
+		struct CmdlineArgData *data = &cmdline->args_data[i];
+		char altname[16], paramnames[256];
+		if (data->shortname) {
+			snprintf(altname, sizeof(altname), " [-%c]", data->shortname);
+		} else {
+			*altname = '\0';
+		}
+		snprintf(paramnames, sizeof(paramnames), "%s%s%s", data->name, altname, data->options&CMDLINE_OPT_PARAM ? " <name>" : "");
+		ShowInfo("  %-30s %s [%s]\n", paramnames, data->help ? data->help : "<no description provided>", cmdline->arg_source(data));
+	}
+	return false;
+}
+/**
+ * Info screen to be displayed by '--version'.
+ */
+static CMDLINEARG(version)
+{
+	ShowInfo(CL_GREEN"Website/Forum:"CL_RESET"\thttp://hercules.ws/\n");
+	ShowInfo(CL_GREEN"IRC Channel:"CL_RESET"\tirc://irc.rizon.net/#Hercules\n");
+	ShowInfo("Open "CL_WHITE"readme.txt"CL_RESET" for more information.\n");
+	return false;
+}
+/**
+ * Checks if there is a value available for the current argument
+ *
+ * @param name        the current argument's name.
+ * @param current_arg the current argument's position.
+ * @param argc        the program's argc.
+ * @return true if a value for the current argument is available on the command line.
+ */
+bool cmdline_arg_next_value(const char *name, int current_arg, int argc)
+{
+	if (current_arg >= argc-1) {
+		ShowError("Missing value for option '%s'.\n", name);
+		return false;
+	}
+
+	return true;
+}
+/**
+ * Executes the command line arguments handlers.
+ *
+ * @param argc    the program's argc
+ * @param argv    the program's argv
+ * @param options Execution options. Allowed values:
+ * - CMDLINE_OPT_SILENT: Scans the argv for a command line argument that
+ *   requires the server's silent mode, and triggers it. Invalid command line
+ *   arguments don't cause it to abort. No command handlers are executed.
+ * - CMDLINE_OPT_PREINIT: Scans the argv for command line arguments with the
+ *   CMDLINE_OPT_PREINIT flag set and executes their handlers. Invalid command
+ *   line arguments don't cause it to abort. Handler's failure causes the
+ *   program to abort.
+ * - CMDLINE_OPT_NORMAL: Scans the argv for normal command line arguments,
+ *   skipping the pre-init ones, and executes their handlers. Invalid command
+ *   line arguments or handler's failure cause the program to abort.
+ * @return the amount of command line handlers successfully executed.
+ */
+int cmdline_exec(int argc, char **argv, unsigned int options)
+{
+	int count = 0, i, j;
+	for (i = 1; i < argc; i++) {
+		struct CmdlineArgData *data = NULL;
+		const char *arg = argv[i];
+		if (arg[0] != '-') { // All arguments must begin with '-'
+			ShowError("Invalid option '%s'.\n", argv[i]);
+			exit(EXIT_FAILURE);
+		}
+		if (arg[1] != '-' && strlen(arg) == 2) {
+			ARR_FIND(0, cmdline->args_data_count, j, cmdline->args_data[j].shortname == arg[1]);
+		} else {
+			ARR_FIND(0, cmdline->args_data_count, j, strcmpi(cmdline->args_data[j].name, arg) == 0);
+		}
+		if (j == cmdline->args_data_count) {
+			if (options&(CMDLINE_OPT_SILENT|CMDLINE_OPT_PREINIT))
+				continue;
+			ShowError("Unknown option '%s'.\n", arg);
+			exit(EXIT_FAILURE);
+		}
+		data = &cmdline->args_data[j];
+		if (data->options&CMDLINE_OPT_PARAM) {
+			if (!cmdline->arg_next_value(arg, i, argc))
+				exit(EXIT_FAILURE);
+			i++;
+		}
+		if (options&CMDLINE_OPT_SILENT) {
+			if (data->options&CMDLINE_OPT_SILENT) {
+				msg_silent = 0x7; // silence information and status messages
+				break;
+			}
+		} else if ((data->options&CMDLINE_OPT_PREINIT) == (options&CMDLINE_OPT_PREINIT)) {
+			const char *param = NULL;
+			if (data->options&CMDLINE_OPT_PARAM) {
+				param = argv[i]; // Already incremented above
+			}
+			if (!data->func(arg, param))
+				exit(EXIT_SUCCESS);
+			count++;
+		}
+	}
+	return count;
+}
+/**
+ * Defines the global command-line arguments.
+ */
+void cmdline_init(void)
+{
+#ifdef MINICORE
+	// Minicore has no HPM. This value isn't used, but the arg_add function requires it, so we're (re)defining it here
+#define HPM_PID_CORE ((unsigned int)-1)
+#endif
+	CMDLINEARG_DEF(help, 'h', "Displays this help screen", CMDLINE_OPT_NORMAL);
+	CMDLINEARG_DEF(version, 'v', "Displays the server's version.", CMDLINE_OPT_NORMAL);
+#ifndef MINICORE
+	CMDLINEARG_DEF2(load-plugin, loadplugin, "Loads an additional plugin (can be repeated).", CMDLINE_OPT_PARAM|CMDLINE_OPT_PREINIT);
+#endif // !MINICORE
+	cmdline_args_init_local();
+}
+void cmdline_final(void)
+{
+	int i;
+	for (i = 0; i < cmdline->args_data_count; i++) {
+		aFree(cmdline->args_data[i].name);
+		aFree(cmdline->args_data[i].help);
+	}
+	if (cmdline->args_data)
+		aFree(cmdline->args_data);
+}
+
+struct cmdline_interface cmdline_s;
+
+void cmdline_defaults(void)
+{
+	cmdline = &cmdline_s;
+
+	cmdline->args_data = NULL;
+	cmdline->args_data_count = 0;
+
+	cmdline->init = cmdline_init;
+	cmdline->final = cmdline_final;
+	cmdline->arg_add = cmdline_arg_add;
+	cmdline->exec = cmdline_exec;
+	cmdline->arg_next_value = cmdline_arg_next_value;
+	cmdline->arg_source = cmdline_arg_source;
+}
 /*======================================
  * CORE : MAINROUTINE
  *--------------------------------------*/
@@ -203,17 +394,14 @@ int main (int argc, char **argv) {
 	}
 	core_defaults();
 
-	{
-		int i;
-		for(i = 0; i < argc; i++) {
-			if( strcmp(argv[i], "--script-check") == 0 ) {
-				msg_silent = 0x7; // silence information and status messages
-			}
-		}
-	}
-
 	iMalloc->init();// needed for Show* in display_title() [FlavioJS]
 
+	cmdline->init();
+
+	cmdline->exec(argc, argv, CMDLINE_OPT_SILENT);
+
+	iMalloc->init_messages(); // Initialization messages (after buying us some time to suppress them if needed)
+	
 	sysinfo->init();
 
 	if (!(msg_silent&0x1))
@@ -269,6 +457,7 @@ int main (int argc, char **argv) {
 	rathread_final();
 	ers_final();
 #endif
+	cmdline->final();
 	//sysinfo->final(); Called by iMalloc->final()
 
 	iMalloc->final();