Merge pull request #482 from OoliteProject/helpOnCmdLine

Introducing -help / --help Command Line Option

Doc/CHANGELOG.TXT

@@ -46,6 +46,8 @@ General:
 * (Windows) Required minimum OS is now Windows 7.
 * Minimum OpenGL version is now 3.3.
 * Application startup command is now written to the log file.
+* Implemented [-]-help command line option - shows list of available command line
+  switches.
 
 Expansion Pack Development:
 ===========================

src/SDL/main.m

@@ -70,7 +70,9 @@ int main(int argc, char *argv[])
 
 #if OOLITE_WINDOWS
 
-	// Detect current working directory and set up GNUstep environment variables
+	#define OO_SHOW_MSG(ooMsg, ooMsgTitle, ooMsgFlags)	MessageBox(NULL, ooMsg, ooMsgTitle, ooMsgFlags)
+
+ 	// Detect current working directory and set up GNUstep environment variables
 	#define MAX_PATH_LEN 256
 	char currentWorkingDir[MAX_PATH_LEN];
 	char envVarString[2 * MAX_PATH_LEN];
@@ -108,6 +110,9 @@ int main(int argc, char *argv[])
 		numbers don't behave strangely.
 	*/
 	setlocale(LC_ALL, "C");
+
+#else // Linux
+	#define OO_SHOW_MSG(ooMsg, ooTitle, ooFlags)	fprintf(stdout, ooMsg)
 #endif
 
 	// Need this because we're not using the default run loop's autorelease
@@ -129,6 +134,35 @@ int main(int argc, char *argv[])
 				if (i < argc)
 					[controller setPlayerFileToLoad: [NSString stringWithCString: argv[i]]];
 			}
+
+   			if (!strcmp("-help", argv[i]) || !strcmp("--help", argv[i]))
+			{
+				char const *processName = [[[NSProcessInfo processInfo] processName] UTF8String];
+				char s[2048];
+				snprintf(s, sizeof(s), "Usage: %s [options]\n\n"
+							"Options can be any of the following: \n\n"
+							"--compile-sysdesc\t\t\tCompile system descriptions *\n"
+							"--export-sysdesc\t\t\tExport system descriptions *\n"
+#if OOLITE_WINDOWS
+							"-hdr\t\t\t\tStart up in HDR mode\n"
+#endif
+							"-load [filepath]:\t\t\tLoad commander from [filepath]\n"
+							"-message [messageString]\t\tDisplay [messageString] at startup\n"
+							"-noshaders\t\t\tStart up with shaders disabled\n"
+							"-nosplash\t\t\t\tForce disable splash screen on startup\n"
+							"-nosound\t\t\t\tStart up with sound disabled\n"
+							"-novsync\t\t\t\tForce disable V-Sync\n"
+							"--openstep\t\t\tWhen compiling or exporting system\n\t\t\t\tdescriptions, use openstep format *\n"
+							"-showversion\t\t\tDisplay version at startup screen\n"
+							"-splash\t\t\t\tForce splash screen on startup\n"
+							"-verify-oxp [filepath]\t\t\tVerify OXP at [filepath] *\n"
+							"--xml\t\t\t\tWhen compiling or exporting system \n\t\t\t\tdescriptions, use xml format *\n"
+							"\n"
+							"Options marked with \"*\" are available only in Test Release configuration.\n\n", processName);
+				OO_SHOW_MSG(s, processName, MB_OK);
+    				OOLog(@"process.args", @"%s option detected, exiting after help page has been displayed.", argv[i]);
+				return 0;
+			}
 		}
 
 		// Release anything allocated during the controller initialisation that