remove backup_subcmd global variable and useless command_name variable

Author: kulaginm

src/help.c

@@ -7,8 +7,10 @@
  *-------------------------------------------------------------------------
  */
 
+#include <assert.h>
 #include "pg_probackup.h"
 
+static void help_nocmd(void);
 static void help_init(void);
 static void help_backup(void);
 static void help_restore(void);
@@ -24,50 +26,52 @@ static void help_del_instance(void);
 static void help_archive_push(void);
 static void help_archive_get(void);
 static void help_checkdb(void);
+static void help_help(void);
 
 void
-help_command(char *command)
+help_print_version(void)
 {
-	if (strcmp(command, "init") == 0)
-		help_init();
-	else if (strcmp(command, "backup") == 0)
-		help_backup();
-	else if (strcmp(command, "restore") == 0)
-		help_restore();
-	else if (strcmp(command, "validate") == 0)
-		help_validate();
-	else if (strcmp(command, "show") == 0)
-		help_show();
-	else if (strcmp(command, "delete") == 0)
-		help_delete();
-	else if (strcmp(command, "merge") == 0)
-		help_merge();
-	else if (strcmp(command, "set-backup") == 0)
-		help_set_backup();
-	else if (strcmp(command, "set-config") == 0)
-		help_set_config();
-	else if (strcmp(command, "show-config") == 0)
-		help_show_config();
-	else if (strcmp(command, "add-instance") == 0)
-		help_add_instance();
-	else if (strcmp(command, "del-instance") == 0)
-		help_del_instance();
-	else if (strcmp(command, "archive-push") == 0)
-		help_archive_push();
-	else if (strcmp(command, "archive-get") == 0)
-		help_archive_get();
-	else if (strcmp(command, "checkdb") == 0)
-		help_checkdb();
-	else if (strcmp(command, "--help") == 0
-			 || strcmp(command, "help") == 0
-			 || strcmp(command, "-?") == 0
-			 || strcmp(command, "--version") == 0
-			 || strcmp(command, "version") == 0
-			 || strcmp(command, "-V") == 0)
-		printf(_("No help page for \"%s\" command. Try pg_probackup help\n"), command);
-	else
-		printf(_("Unknown command \"%s\". Try pg_probackup help\n"), command);
-	exit(0);
+#ifdef PGPRO_VERSION
+	fprintf(stdout, "%s %s (Postgres Pro %s %s)\n",
+			PROGRAM_NAME, PROGRAM_VERSION,
+			PGPRO_VERSION, PGPRO_EDITION);
+#else
+	fprintf(stdout, "%s %s (PostgreSQL %s)\n",
+			PROGRAM_NAME, PROGRAM_VERSION, PG_VERSION);
+#endif
+}
+
+void
+help_command(ProbackupSubcmd const subcmd)
+{
+	typedef void (* help_function_ptr)(void);
+	/* Order is important, keep it in sync with utils/configuration.h:enum ProbackupSubcmd declaration */
+	static help_function_ptr const help_functions[] =
+	{
+		&help_nocmd,
+		&help_init,
+		&help_add_instance,
+		&help_del_instance,
+		&help_archive_push,
+		&help_archive_get,
+		&help_backup,
+		&help_restore,
+		&help_validate,
+		&help_delete,
+		&help_merge,
+		&help_show,
+		&help_set_config,
+		&help_set_backup,
+		&help_show_config,
+		&help_checkdb,
+		&help_nocmd, // SSH_CMD
+		&help_nocmd, // AGENT_CMD
+		&help_help,
+		&help_help, // VERSION_CMD
+	};
+
+	Assert((int)subcmd < sizeof(help_functions) / sizeof(help_functions[0]));
+        help_functions[(int)subcmd]();
 }
 
 void
@@ -247,7 +251,12 @@ help_pg_probackup(void)
 		if (PROGRAM_EMAIL)
 			printf("Report bugs to <%s>.\n", PROGRAM_EMAIL);
 	}
-	exit(0);
+}
+
+static void
+help_nocmd(void)
+{
+	printf(_("Unknown command. Try pg_probackup help\n"));
 }
 
 static void
@@ -971,3 +980,9 @@ help_archive_get(void)
 	printf(_("      --ssh-options=ssh_options    additional ssh options (default: none)\n"));
 	printf(_("                                   (example: --ssh-options='-c cipher_spec -F configfile')\n\n"));
 }
+
+static void
+help_help(void)
+{
+	printf(_("No help page required for \"help\" and \"version\" commands. Just try it!\n"));
+}