text: /*
   *	option.c
   *
   *	options functions
   *
   *	Copyright (c) 2010-2021, PostgreSQL Global Development Group
   *	src/bin/pg_upgrade/option.c
   */
  
  #include "postgres_fe.h"
  
  #include <time.h>
  #ifdef WIN32
  #include <io.h>
  #endif
  
  #include "common/string.h"
  #include "getopt_long.h"
  #include "pg_upgrade.h"
  #include "utils/pidfile.h"
  
  static void usage(void);
  static void check_required_directory(char **dirpath,
  									 const char *envVarName, bool useCwd,
  									 const char *cmdLineOption, const char *description,
  									 bool missingOk);
  #define FIX_DEFAULT_READ_ONLY "-c default_transaction_read_only=false"
  
  
  UserOpts	user_opts;
  
  
  /*
   * parseCommandLine()
   *
   *	Parses the command line (argc, argv[]) and loads structures
   */
  void
  parseCommandLine(int argc, char *argv[])
  {
  	static struct option long_options[] = {
  		{"old-datadir", required_argument, NULL, 'd'},
  		{"new-datadir", required_argument, NULL, 'D'},
  		{"old-bindir", required_argument, NULL, 'b'},
  		{"new-bindir", required_argument, NULL, 'B'},
  		{"no-sync", no_argument, NULL, 'N'},
  		{"old-options", required_argument, NULL, 'o'},
  		{"new-options", required_argument, NULL, 'O'},
  		{"old-port", required_argument, NULL, 'p'},
  		{"new-port", required_argument, NULL, 'P'},
  
  		{"username", required_argument, NULL, 'U'},
  		{"check", no_argument, NULL, 'c'},
  		{"link", no_argument, NULL, 'k'},
  		{"retain", no_argument, NULL, 'r'},
  		{"jobs", required_argument, NULL, 'j'},
  		{"socketdir", required_argument, NULL, 's'},
  		{"verbose", no_argument, NULL, 'v'},
  		{"clone", no_argument, NULL, 1},
  
  		{NULL, 0, NULL, 0}
  	};
  	int			option;			/* Command line option */
  	int			optindex = 0;	/* used by getopt_long */
  	int			os_user_effective_id;
  	FILE	   *fp;
  	char	  **filename;
  	time_t		run_time = time(NULL);
  
  	user_opts.do_sync = true;
  	user_opts.transfer_mode = TRANSFER_MODE_COPY;
  
  	os_info.progname = get_progname(argv[0]);
  
  	/* Process libpq env. variables; load values here for usage() output */
  	old_cluster.port = getenv("PGPORTOLD") ? atoi(getenv("PGPORTOLD")) : DEF_PGUPORT;
  	new_cluster.port = getenv("PGPORTNEW") ? atoi(getenv("PGPORTNEW")) : DEF_PGUPORT;
  
  	os_user_effective_id = get_user_info(&os_info.user);
  	/* we override just the database user name;  we got the OS id above */
  	if (getenv("PGUSER"))
  	{
  		pg_free(os_info.user);
  		/* must save value, getenv()'s pointer is not stable */
  		os_info.user = pg_strdup(getenv("PGUSER"));
  	}
  
  	if (argc > 1)
  	{
  		if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
  		{
  			usage();
  			exit(0);
  		}
  		if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
  		{
  			puts("pg_upgrade (PostgreSQL) " PG_VERSION);
  			exit(0);
  		}
  	}
  
  	/* Allow help and version to be run as root, so do the test here. */
  	if (os_user_effective_id == 0)
  		pg_fatal("%s: cannot be run as root\n", os_info.progname);
  
  	while ((option = getopt_long(argc, argv, "d:D:b:B:cj:kNo:O:p:P:rs:U:v",
  								 long_options, &optindex)) != -1)
  	{
  		switch (option)
  		{
  			case 'b':
  				old_cluster.bindir = pg_strdup(optarg);
  				break;
  
  			case 'B':
  				new_cluster.bindir = pg_strdup(optarg);
  				break;
  
  			case 'c':
  				user_opts.check = true;
  				break;
  
  			case 'd':
  				old_cluster.pgdata = pg_strdup(optarg);
  				break;
  
  			case 'D':
  				new_cluster.pgdata = pg_strdup(optarg);
  				break;
  
  			case 'j':
  				user_opts.jobs = atoi(optarg);
  				break;
  
  			case 'k':
  				user_opts.transfer_mode = TRANSFER_MODE_LINK;
  				break;
  
  			case 'N':
  				user_opts.do_sync = false;
  				break;
  
  			case 'o':
  				/* append option? */
  				if (!old_cluster.pgopts)
  					old_cluster.pgopts = pg_strdup(optarg);
  				else
  				{
  					char	   *old_pgopts = old_cluster.pgopts;
  
  					old_cluster.pgopts = psprintf("%s %s", old_pgopts, optarg);
  					free(old_pgopts);
  				}
  				break;
  
  			case 'O':
  				/* append option? */
  				if (!new_cluster.pgopts)
  					new_cluster.pgopts = pg_strdup(optarg);
  				else
  				{
  					char	   *new_pgopts = new_cluster.pgopts;
  
  					new_cluster.pgopts = psprintf("%s %s", new_pgopts, optarg);
  					free(new_pgopts);
  				}
  				break;
  
  			case 'p':
  				if ((old_cluster.port = atoi(optarg)) <= 0)
  					pg_fatal("invalid old port number\n");
  				break;
  
  			case 'P':
  				if ((new_cluster.port = atoi(optarg)) <= 0)
  					pg_fatal("invalid new port number\n");
  				break;
  
  			case 'r':
  				log_opts.retain = true;
  				break;
  
  			case 's':
  				user_opts.socketdir = pg_strdup(optarg);
  				break;
  
  			case 'U':
  				pg_free(os_info.user);
  				os_info.user = pg_strdup(optarg);
  				os_info.user_specified = true;
  				break;
  
  			case 'v':
  				log_opts.verbose = true;
  				break;
  
  			case 1:
  				user_opts.transfer_mode = TRANSFER_MODE_CLONE;
  				break;
  
  			default:
  				fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
  						os_info.progname);
  				exit(1);
  		}
  	}
  
  	if (optind < argc)
  		pg_fatal("too many command-line arguments (first is \"%s\")\n", argv[optind]);
  
  	if ((log_opts.internal = fopen_priv(INTERNAL_LOG_FILE, "a")) == NULL)
  		pg_fatal("could not open log file \"%s\": %m\n", INTERNAL_LOG_FILE);
  
  	if (log_opts.verbose)
  		pg_log(PG_REPORT, "Running in verbose mode\n");
  
  	/* label start of upgrade in logfiles */
  	for (filename = output_files; *filename != NULL; filename++)
  	{
  		if ((fp = fopen_priv(*filename, "a")) == NULL)
  			pg_fatal("could not write to log file \"%s\": %m\n", *filename);
  
  		/* Start with newline because we might be appending to a file. */
  		fprintf(fp, "\n"
  				"-----------------------------------------------------------------\n"
  				"  pg_upgrade run on %s"
  				"-----------------------------------------------------------------\n\n",
  				ctime(&run_time));
  		fclose(fp);
  	}
  
  	/* Turn off read-only mode;  add prefix to PGOPTIONS? */
  	if (getenv("PGOPTIONS"))
  	{
  		char	   *pgoptions = psprintf("%s %s", FIX_DEFAULT_READ_ONLY,
  										 getenv("PGOPTIONS"));
  
  		setenv("PGOPTIONS", pgoptions, 1);
  		pfree(pgoptions);
  	}
  	else
  		setenv("PGOPTIONS", FIX_DEFAULT_READ_ONLY, 1);
  
  	/* Get values from env if not already set */
  	check_required_directory(&old_cluster.bindir, "PGBINOLD", false,
  							 "-b", _("old cluster binaries reside"), false);
  	check_required_directory(&new_cluster.bindir, "PGBINNEW", false,
  							 "-B", _("new cluster binaries reside"), true);
  	check_required_directory(&old_cluster.pgdata, "PGDATAOLD", false,
  							 "-d", _("old cluster data resides"), false);
  	check_required_directory(&new_cluster.pgdata, "PGDATANEW", false,
  							 "-D", _("new cluster data resides"), false);
  	check_required_directory(&user_opts.socketdir, "PGSOCKETDIR", true,
  							 "-s", _("sockets will be created"), false);
  
  #ifdef WIN32
  
  	/*
  	 * On Windows, initdb --sync-only will fail with a "Permission denied"
  	 * error on file pg_upgrade_utility.log if pg_upgrade is run inside the
  	 * new cluster directory, so we do a check here.
  	 */
  	{
  		char		cwd[MAXPGPATH],
  					new_cluster_pgdata[MAXPGPATH];
  
  		strlcpy(new_cluster_pgdata, new_cluster.pgdata, MAXPGPATH);
  		canonicalize_path(new_cluster_pgdata);
  
  		if (!getcwd(cwd, MAXPGPATH))
  			pg_fatal("could not determine current directory\n");
  		canonicalize_path(cwd);
  		if (path_is_prefix_of_path(new_cluster_pgdata, cwd))
  			pg_fatal("cannot run pg_upgrade from inside the new cluster data directory on Windows\n");
  	}
  #endif
  }
  
  
  static void
  usage(void)
  {
  	printf(_("pg_upgrade upgrades a PostgreSQL cluster to a different major version.\n\n"));
  	printf(_("Usage:\n"));
  	printf(_("  pg_upgrade [OPTION]...\n\n"));
  	printf(_("Options:\n"));
  	printf(_("  -b, --old-bindir=BINDIR       old cluster executable directory\n"));
  	printf(_("  -B, --new-bindir=BINDIR       new cluster executable directory (default\n"
  			 "                                same directory as pg_upgrade)\n"));
  	printf(_("  -c, --check                   check clusters only, don't change any data\n"));
  	printf(_("  -d, --old-datadir=DATADIR     old cluster data directory\n"));
  	printf(_("  -D, --new-datadir=DATADIR     new cluster data directory\n"));
  	printf(_("  -j, --jobs=NUM                number of simultaneous processes or threads to use\n"));
  	printf(_("  -k, --link                    link instead of copying files to new cluster\n"));
  	printf(_("  -N, --no-sync                 do not wait for changes to be written safely to disk\n"));
  	printf(_("  -o, --old-options=OPTIONS     old cluster options to pass to the server\n"));
  	printf(_("  -O, --new-options=OPTIONS     new cluster options to pass to the server\n"));
  	printf(_("  -p, --old-port=PORT           old cluster port number (default %d)\n"), old_cluster.port);
  	printf(_("  -P, --new-port=PORT           new cluster port number (default %d)\n"), new_cluster.port);
  	printf(_("  -r, --retain                  retain SQL and log files after success\n"));
  	printf(_("  -s, --socketdir=DIR           socket directory to use (default current dir.)\n"));
  	printf(_("  -U, --username=NAME           cluster superuser (default \"%s\")\n"), os_info.user);
  	printf(_("  -v, --verbose                 enable verbose internal logging\n"));
  	printf(_("  -V, --version                 display version information, then exit\n"));
  	printf(_("  --clone                       clone instead of copying files to new cluster\n"));
  	printf(_("  -?, --help                    show this help, then exit\n"));
  	printf(_("\n"
  			 "Before running pg_upgrade you must:\n"
  			 "  create a new database cluster (using the new version of initdb)\n"
  			 "  shutdown the postmaster servicing the old cluster\n"
  			 "  shutdown the postmaster servicing the new cluster\n"));
  	printf(_("\n"
  			 "When you run pg_upgrade, you must provide the following information:\n"
  			 "  the data directory for the old cluster  (-d DATADIR)\n"
  			 "  the data directory for the new cluster  (-D DATADIR)\n"
  			 "  the \"bin\" directory for the old version (-b BINDIR)\n"
  			 "  the \"bin\" directory for the new version (-B BINDIR)\n"));
  	printf(_("\n"
  			 "For example:\n"
  			 "  pg_upgrade -d oldCluster/data -D newCluster/data -b oldCluster/bin -B newCluster/bin\n"
  			 "or\n"));
  #ifndef WIN32
  	printf(_("  $ export PGDATAOLD=oldCluster/data\n"
  			 "  $ export PGDATANEW=newCluster/data\n"
  			 "  $ export PGBINOLD=oldCluster/bin\n"
  			 "  $ export PGBINNEW=newCluster/bin\n"
  			 "  $ pg_upgrade\n"));
  #else
  	printf(_("  C:\\> set PGDATAOLD=oldCluster/data\n"
  			 "  C:\\> set PGDATANEW=newCluster/data\n"
  			 "  C:\\> set PGBINOLD=oldCluster/bin\n"
  			 "  C:\\> set PGBINNEW=newCluster/bin\n"
  			 "  C:\\> pg_upgrade\n"));
  #endif
  	printf(_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
  	printf(_("%s home page: <%s>\n"), PACKAGE_NAME, PACKAGE_URL);
  }
  
  
  /*
   * check_required_directory()
   *
   * Checks a directory option.
   *	dirpath		  - the directory name supplied on the command line, or NULL
   *	envVarName	  - the name of an environment variable to get if dirpath is NULL
   *	useCwd		  - true if OK to default to CWD
   *	cmdLineOption - the command line option for this directory
   *	description   - a description of this directory option
   *	missingOk	  - true if OK that both dirpath and envVarName are not existing
   *
   * We use the last two arguments to construct a meaningful error message if the
   * user hasn't provided the required directory name.
   */
  static void
  check_required_directory(char **dirpath, const char *envVarName, bool useCwd,
  						 const char *cmdLineOption, const char *description,
  						 bool missingOk)
  {
  	if (*dirpath == NULL || strlen(*dirpath) == 0)
  	{
  		const char *envVar;
  
  		if ((envVar = getenv(envVarName)) && strlen(envVar))
  			*dirpath = pg_strdup(envVar);
  		else if (useCwd)
  		{
  			char		cwd[MAXPGPATH];
  
  			if (!getcwd(cwd, MAXPGPATH))
  				pg_fatal("could not determine current directory\n");
  			*dirpath = pg_strdup(cwd);
  		}
  		else if (missingOk)
  			return;
  		else
  			pg_fatal("You must identify the directory where the %s.\n"
  					 "Please use the %s command-line option or the %s environment variable.\n",
  					 description, cmdLineOption, envVarName);
  	}
  
  	/*
  	 * Clean up the path, in particular trimming any trailing path separators,
  	 * because we construct paths by appending to this path.
  	 */
  	canonicalize_path(*dirpath);
  }
  
  /*
   * adjust_data_dir
   *
   * If a configuration-only directory was specified, find the real data dir
   * by querying the running server.  This has limited checking because we
   * can't check for a running server because we can't find postmaster.pid.
   *
   * On entry, cluster->pgdata has been set from command line or env variable,
   * but cluster->pgconfig isn't set.  We fill both variables with corrected
   * values.
   */
  void
  adjust_data_dir(ClusterInfo *cluster)
  {
  	char		filename[MAXPGPATH];
  	char		cmd[MAXPGPATH],
  				cmd_output[MAX_STRING];
  	FILE	   *fp,
  			   *output;
  
  	/* Initially assume config dir and data dir are the same */
  	cluster->pgconfig = pg_strdup(cluster->pgdata);
  
  	/* If there is no postgresql.conf, it can't be a config-only dir */
  	snprintf(filename, sizeof(filename), "%s/postgresql.conf", cluster->pgconfig);
  	if ((fp = fopen(filename, "r")) == NULL)
  		return;
  	fclose(fp);
  
  	/* If PG_VERSION exists, it can't be a config-only dir */
  	snprintf(filename, sizeof(filename), "%s/PG_VERSION", cluster->pgconfig);
  	if ((fp = fopen(filename, "r")) != NULL)
  	{
  		fclose(fp);
  		return;
  	}
  
  	/* Must be a configuration directory, so find the real data directory. */
  
  	if (cluster == &old_cluster)
  		prep_status("Finding the real data directory for the source cluster");
  	else
  		prep_status("Finding the real data directory for the target cluster");
  
  	/*
  	 * We don't have a data directory yet, so we can't check the PG version,
  	 * so this might fail --- only works for PG 9.2+.   If this fails,
  	 * pg_upgrade will fail anyway because the data files will not be found.
  	 */
  	snprintf(cmd, sizeof(cmd), "\"%s/postgres\" -D \"%s\" -C data_directory",
  			 cluster->bindir, cluster->pgconfig);
  
  	if ((output = popen(cmd, "r")) == NULL ||
  		fgets(cmd_output, sizeof(cmd_output), output) == NULL)
  		pg_fatal("could not get data directory using %s: %s\n",
  				 cmd, strerror(errno));
  
  	pclose(output);
  
  	/* strip trailing newline and carriage return */
  	(void) pg_strip_crlf(cmd_output);
  
  	cluster->pgdata = pg_strdup(cmd_output);
  
  	check_ok();
  }
  
  
  /*
   * get_sock_dir
   *
   * Identify the socket directory to use for this cluster.  If we're doing
   * a live check (old cluster only), we need to find out where the postmaster
   * is listening.  Otherwise, we're going to put the socket into the current
   * directory.
   */
  void
  get_sock_dir(ClusterInfo *cluster, bool live_check)
  {
  #if defined(HAVE_UNIX_SOCKETS) && !defined(WIN32)
  	if (!live_check)
  		cluster->sockdir = user_opts.socketdir;
  	else
  	{
  		/*
  		 * If we are doing a live check, we will use the old cluster's Unix
  		 * domain socket directory so we can connect to the live server.
  		 */
  		unsigned short orig_port = cluster->port;
  		char		filename[MAXPGPATH],
  					line[MAXPGPATH];
  		FILE	   *fp;
  		int			lineno;
  
  		snprintf(filename, sizeof(filename), "%s/postmaster.pid",
  				 cluster->pgdata);
  		if ((fp = fopen(filename, "r")) == NULL)
  			pg_fatal("could not open file \"%s\": %s\n",
  					 filename, strerror(errno));
  
  		for (lineno = 1;
  			 lineno <= Max(LOCK_FILE_LINE_PORT, LOCK_FILE_LINE_SOCKET_DIR);
  			 lineno++)
  		{
  			if (fgets(line, sizeof(line), fp) == NULL)
  				pg_fatal("could not read line %d from file \"%s\": %s\n",
  						 lineno, filename, strerror(errno));
  
  			/* potentially overwrite user-supplied value */
  			if (lineno == LOCK_FILE_LINE_PORT)
  				sscanf(line, "%hu", &old_cluster.port);
  			if (lineno == LOCK_FILE_LINE_SOCKET_DIR)
  			{
  				/* strip trailing newline and carriage return */
  				cluster->sockdir = pg_strdup(line);
  				(void) pg_strip_crlf(cluster->sockdir);
  			}
  		}
  		fclose(fp);
  
  		/* warn of port number correction */
  		if (orig_port != DEF_PGUPORT && old_cluster.port != orig_port)
  			pg_log(PG_WARNING, "user-supplied old port number %hu corrected to %hu\n",
  				   orig_port, cluster->port);
  	}
  #else							/* !HAVE_UNIX_SOCKETS || WIN32 */
  	cluster->sockdir = NULL;
  #endif
  }
  