I'm continuing to work on cleaning up code in psql. As things appear

now, my changes seem to work.  Some possible minor bugs got squished
on the way but I can't be sure without more feedback from people who
really put the code to the test.

The new patch mostly simplifies variable handling and reduces code
duplication.  Changes in the command parser eliminate some redundant
variables (boolean state + depth counter), replaces some
"else if" constructs with switches, and so on.  It is meant to be
applied together with my previous patch, although I hope they don't
conflict; I went back to the CVS version for this one.

One more thing I thought should perhaps be changed: an IGNOREEOF
value of n will ignore only n-1 EOFs.  I didn't want to touch this
for fear of breaking existing applications, but it does seem a tad
illogical.

Jeroen T. Vermeulen

src/bin/psql/command.c

@@ -3,7 +3,7 @@
  *
  * Copyright 2000-2002 by PostgreSQL Global Development Group
  *
- * $Header: /cvsroot/pgsql/src/bin/psql/command.c,v 1.93 2003/03/19 22:49:43 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/bin/psql/command.c,v 1.94 2003/03/20 06:43:35 momjian Exp $
  */
 #include "postgres_fe.h"
 #include "command.h"
@@ -669,15 +669,7 @@ exec_command(const char *cmd,
 		if (!opt0)
 		{
 			/* list all variables */
-
-			/*
-			 * XXX This is in utter violation of the GetVariable
-			 * abstraction, but I have not bothered to do it better.
-			 */
-			struct _variable *ptr;
-
-			for (ptr = pset.vars; ptr->next; ptr = ptr->next)
-				fprintf(stdout, "%s = '%s'\n", ptr->next->name, ptr->next->value);
+			PrintVariables(pset.vars);
 			success = true;
 		}
 		else
@@ -1073,9 +1065,7 @@ scan_option(char **string, enum option_type type, char *quote, bool semicolon)
 				save_char = options_string[pos + token_end + 1];
 				options_string[pos + token_end + 1] = '\0';
 				value = GetVariable(pset.vars, options_string + pos + 1);
-				if (!value)
-					value = "";
-				return_val = xstrdup(value);
+				return_val = xstrdup(value ? value : "");
 				options_string[pos + token_end + 1] = save_char;
 				*string = &options_string[pos + token_end + 1];
 				/* XXX should we set *quote to ':' here? */
@@ -1287,15 +1277,9 @@ unescape(const unsigned char *source, size_t len)
 				case '7':
 				case '8':
 				case '9':
-					{
-						long int	l;
-						char	   *end;
-
-						l = strtol(p, &end, 0);
-						c = (char) l;
-						p = end - 1;
+					c = parse_char((char **)&p);
 						break;
-					}
+
 				default:
 					c = *p;
 			}

src/bin/psql/common.c

@@ -3,7 +3,7 @@
  *
  * Copyright 2000 by PostgreSQL Global Development Group
  *
- * $Header: /cvsroot/pgsql/src/bin/psql/common.c,v 1.59 2003/03/20 06:00:12 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/bin/psql/common.c,v 1.60 2003/03/20 06:43:35 momjian Exp $
  */
 #include "postgres_fe.h"
 #include "common.h"
@@ -368,7 +368,7 @@ PSQLexec(const char *query, bool ignore_command_ok)
 {
 	PGresult   *res = NULL;
 	PGresult   *newres;
-	const char *var;
+	int	echo_hidden;
 	ExecStatusType rstatus;
 
 	if (!pset.db)
@@ -377,17 +377,17 @@ PSQLexec(const char *query, bool ignore_command_ok)
 		return NULL;
 	}
 
-	var = GetVariable(pset.vars, "ECHO_HIDDEN");
-	if (var)
+	echo_hidden = SwitchVariable(pset.vars, "ECHO_HIDDEN", "noexec", NULL);
+	if (echo_hidden != var_notset)
 	{
 		printf("********* QUERY **********\n"
 			   "%s\n"
 			   "**************************\n\n", query);
 		fflush(stdout);
-	}
 
-	if (var && strcmp(var, "noexec") == 0)
+		if (echo_hidden == 1)
 		return NULL;
+	}
 
 	/* discard any uneaten results of past queries */
 	while ((newres = PQgetResult(pset.db)) != NULL)
@@ -579,13 +579,13 @@ SendQuery(const char *query)
 	bool OK;
 
 	if (!pset.db)
-			{
+	{
 		psql_error("You are currently not connected to a database.\n");
 		return false;
-			}
+	}
 
 	if (GetVariableBool(pset.vars, "SINGLESTEP"))
-			{
+	{
 		char		buf[3];
 
 		printf(gettext("***(Single step mode: Verify query)*********************************************\n"
@@ -596,14 +596,9 @@ SendQuery(const char *query)
 		if (fgets(buf, sizeof(buf), stdin) != NULL)
 			if (buf[0] == 'x')
 				return false;
-			}
-			else
-		{
-		const char *var = GetVariable(pset.vars, "ECHO");
-
-		if (var && strncmp(var, "queries", strlen(var)) == 0)
-			puts(query);
 	}
+	else if (VariableEquals(pset.vars, "ECHO", "queries"))
+		puts(query);
 
 	SetCancelConn();
 
@@ -619,3 +614,15 @@ SendQuery(const char *query)
 	PrintNotifications();
 	return OK;
 }
+
+
+char parse_char(char **buf)
+{
+  long l;
+
+  l = strtol(*buf, buf, 0);
+  (*buf)--;
+  return (char)l;
+}
+
+

src/bin/psql/common.h

@@ -3,7 +3,7 @@
  *
  * Copyright 2000 by PostgreSQL Global Development Group
  *
- * $Header: /cvsroot/pgsql/src/bin/psql/common.h,v 1.23 2003/03/20 06:00:12 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/bin/psql/common.h,v 1.24 2003/03/20 06:43:35 momjian Exp $
  */
 #ifndef COMMON_H
 #define COMMON_H
@@ -42,6 +42,12 @@ extern bool SendQuery(const char *query);
 /* sprompt.h */
 extern char *simple_prompt(const char *prompt, int maxlen, bool echo);
 
+/* Parse a numeric character code from the string pointed at by *buf, e.g.
+ * one written as 0x0c (hexadecimal) or 015 (octal); advance *buf to the last
+ * character of the numeric character code.
+ */
+extern char parse_char(char **buf);
+
 /* Used for all Win32 popen/pclose calls */
 #ifdef WIN32
 #define popen(x,y) _popen(x,y)

src/bin/psql/input.c

@@ -3,7 +3,7 @@
  *
  * Copyright 2000 by PostgreSQL Global Development Group
  *
- * $Header: /cvsroot/pgsql/src/bin/psql/input.c,v 1.22 2003/03/20 06:00:12 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/bin/psql/input.c,v 1.23 2003/03/20 06:43:35 momjian Exp $
  */
 #include "postgres_fe.h"
 #include "input.h"
@@ -233,10 +233,12 @@ finishInput(int exitstatus, void *arg)
 									strlen(PSQLHISTORY) + 1);
 			if (psql_history)
 			{
-				const char *var = GetVariable(pset.vars, "HISTSIZE");
+				int hist_size;
+				hist_size = GetVariableNum(pset.vars,"HISTSIZE",-1,-1,true);
+
+				if (hist_size >= 0)
+					stifle_history(hist_size);
 
-				if (var)
-					stifle_history(atoi(var));
 				sprintf(psql_history, "%s/%s", home, PSQLHISTORY);
 				write_history(psql_history);
 				free(psql_history);

src/bin/psql/large_obj.c

@@ -3,7 +3,7 @@
  *
  * Copyright 2000-2002 by PostgreSQL Global Development Group
  *
- * $Header: /cvsroot/pgsql/src/bin/psql/large_obj.c,v 1.23 2002/10/15 02:24:16 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/bin/psql/large_obj.c,v 1.24 2003/03/20 06:43:35 momjian Exp $
  */
 #include "postgres_fe.h"
 #include "large_obj.h"
@@ -40,15 +40,20 @@ _my_notice_handler(void *arg, const char *message)
 static bool
 handle_transaction(void)
 {
-	const char *var = GetVariable(pset.vars, "LO_TRANSACTION");
 	PGresult   *res;
-	bool		commit;
+	bool		commit = false;
 	PQnoticeProcessor old_notice_hook;
 
-	if (var && strcmp(var, "nothing") == 0)
+	switch (SwitchVariable(pset.vars, "LO_TRANSACTION", 
+									"nothing", 
+									"commit", 
+									NULL))
+	{
+	  case 1:
 		return true;
-
-	commit = (var && strcmp(var, "commit") == 0);
+	  case 2:
+		 commit = true;
+	}
 
 	notice[0] = '\0';
 	old_notice_hook = PQsetNoticeProcessor(pset.db, _my_notice_handler, NULL);
@@ -87,11 +92,9 @@ do_lo_export(const char *loid_arg, const char *filename_arg)
 {
 	PGresult   *res;
 	int			status;
-	bool		own_transaction = true;
-	const char *var = GetVariable(pset.vars, "LO_TRANSACTION");
+	bool		own_transaction;
 
-	if (var && strcmp(var, "nothing") == 0)
-		own_transaction = false;
+	own_transaction = VariableEquals(pset.vars, "LO_TRANSACTION", "nothing");
 
 	if (!pset.db)
 	{
@@ -154,11 +157,9 @@ do_lo_import(const char *filename_arg, const char *comment_arg)
 	Oid			loid;
 	char		oidbuf[32];
 	unsigned int i;
-	bool		own_transaction = true;
-	const char *var = GetVariable(pset.vars, "LO_TRANSACTION");
+	bool		own_transaction;
 
-	if (var && strcmp(var, "nothing") == 0)
-		own_transaction = false;
+	own_transaction = VariableEquals(pset.vars, "LO_TRANSACTION", "nothing");
 
 	if (!pset.db)
 	{
@@ -271,11 +272,10 @@ do_lo_unlink(const char *loid_arg)
 	int			status;
 	Oid			loid = atooid(loid_arg);
 	char		buf[256];
-	bool		own_transaction = true;
-	const char *var = GetVariable(pset.vars, "LO_TRANSACTION");
 
-	if (var && strcmp(var, "nothing") == 0)
-		own_transaction = false;
+	bool		own_transaction;
+
+	own_transaction = VariableEquals(pset.vars, "LO_TRANSACTION", "nothing");
 
 	if (!pset.db)
 	{

src/bin/psql/mainloop.c

@@ -3,7 +3,7 @@
  *
  * Copyright 2000 by PostgreSQL Global Development Group
  *
- * $Header: /cvsroot/pgsql/src/bin/psql/mainloop.c,v 1.52 2003/03/20 06:00:12 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/bin/psql/mainloop.c,v 1.53 2003/03/20 06:43:35 momjian Exp $
  */
 #include "postgres_fe.h"
 #include "mainloop.h"
@@ -40,16 +40,14 @@ MainLoop(FILE *source)
 	char	   *line;			/* current line of input */
 	int			len;			/* length of the line */
 	volatile int successResult = EXIT_SUCCESS;
-	volatile backslashResult slashCmdStatus;
+	volatile backslashResult slashCmdStatus = CMD_UNKNOWN;
 
 	bool		success;
-	volatile char in_quote;		/* == 0 for no in_quote */
-	volatile bool in_xcomment;	/* in extended comment */
-	volatile int xcdepth;
-	volatile int paren_level;
+	volatile char in_quote = 0;		/* == 0 for no in_quote */
+	volatile int in_xcomment = 0;	/* in extended comment */
+	volatile int paren_level = 0;
 	unsigned int query_start;
 	volatile int count_eof = 0;
-	const char *var;
 	volatile unsigned int bslash_count = 0;
 
 	int			i,
@@ -81,16 +79,12 @@ MainLoop(FILE *source)
 		exit(EXIT_FAILURE);
 	}
 
-	in_xcomment = false;
-	in_quote = 0;
-	paren_level = 0;
-	slashCmdStatus = CMD_UNKNOWN;		/* set default */
 	prev_lineno = pset.lineno;
 	pset.lineno = 0;
 
 
 	/* main loop to get queries and execute them */
-	while (1)
+	while (successResult == EXIT_SUCCESS)
 	{
 		/*
 		 * Welcome code for Control-C
@@ -109,6 +103,7 @@ MainLoop(FILE *source)
 			}
 
 			cancel_pressed = false;
+			fflush(stdout);
 		}
 
 #ifndef WIN32
@@ -118,15 +113,16 @@ MainLoop(FILE *source)
 
 			if (pset.cur_cmd_interactive)
 			{
-				fputc('\n', stdout);
+				putc('\n', stdout);
 				resetPQExpBuffer(query_buf);
 
 				/* reset parsing state */
-				in_xcomment = false;
+				in_xcomment = 0;
 				in_quote = 0;
 				paren_level = 0;
 				count_eof = 0;
 				slashCmdStatus = CMD_UNKNOWN;
+				fflush(stdout);
 			}
 			else
 			{
@@ -151,23 +147,21 @@ MainLoop(FILE *source)
 			line = xstrdup(query_buf->data);
 			resetPQExpBuffer(query_buf);
 			/* reset parsing state since we are rescanning whole line */
-			in_xcomment = false;
+			in_xcomment = 0;
 			in_quote = 0;
 			paren_level = 0;
 			slashCmdStatus = CMD_UNKNOWN;
 		}
-		else
-		{
-			fflush(stdout);
-
 			/*
 			 * otherwise, set interactive prompt if necessary and get
 			 * another line
 			 */
-			if (pset.cur_cmd_interactive)
+		else if (pset.cur_cmd_interactive)
 			{
 				int			prompt_status;
 
+			fflush(stdout);
+
 				if (in_quote && in_quote == '\'')
 					prompt_status = PROMPT_SINGLEQUOTE;
 				else if (in_quote && in_quote == '"')
@@ -185,7 +179,6 @@ MainLoop(FILE *source)
 			}
 			else
 				line = gets_fromFile(source);
-		}
 
 
 		/* Setting this will not have effect until next line. */
@@ -203,50 +196,21 @@ MainLoop(FILE *source)
 		{
 			if (pset.cur_cmd_interactive)
 			{
-				bool		getout = true;
-
 				/* This tries to mimic bash's IGNOREEOF feature. */
-				const char *val = GetVariable(pset.vars, "IGNOREEOF");
-
-				if (val)
-				{
-					long int	maxeof;
-					char	   *endptr;
-
-					if (*val == '\0')
-						maxeof = 10;
-					else
-					{
-						maxeof = strtol(val, &endptr, 0);
-						if (*endptr != '\0')	/* string not valid as a
-												 * number */
-							maxeof = 10;
-					}
-
-					if (count_eof++ != maxeof)
-						getout = false; /* not quite there yet */
-				}
+				count_eof++;
 
-				if (getout)
-				{
-					if (QUIET())
-						putc('\n', stdout);
-					else
-						puts("\\q");
-					break;
-				}
-				else
+				if (count_eof < GetVariableNum(pset.vars,"IGNOREEOF",0,10,false))
 				{
 					if (!QUIET())
 						printf(gettext("Use \"\\q\" to leave %s.\n"), pset.progname);
 					continue;
 				}
+
+				puts(QUIET() ? "" : "\\q");
 			}
-			else
-/* not interactive */
 				break;
 		}
-		else
+
 			count_eof = 0;
 
 		pset.lineno++;
@@ -259,8 +223,7 @@ MainLoop(FILE *source)
 		}
 
 		/* echo back if flag is set */
-		var = GetVariable(pset.vars, "ECHO");
-		if (!pset.cur_cmd_interactive && var && strcmp(var, "all") == 0)
+		if (!pset.cur_cmd_interactive && VariableEquals(pset.vars, "ECHO", "all"))
 			puts(line);
 		fflush(stdout);
 
@@ -276,14 +239,13 @@ MainLoop(FILE *source)
 #define ADVANCE_1 (prevlen = thislen, i += thislen, thislen = PQmblen(line+i, pset.encoding))
 
 		success = true;
-		for (i = 0, prevlen = 0, thislen = (len > 0) ? PQmblen(line, pset.encoding) : 0;
-			 i < len;
-			 ADVANCE_1)
+		prevlen = 0;
+		thislen = ((len > 0) ? PQmblen(line, pset.encoding) : 0);
+
+		for (i = 0; (i < len) && (success || !die_on_error); ADVANCE_1)
 		{
 			/* was the previous character a backslash? */
-			bool		was_bslash = (i > 0 && line[i - prevlen] == '\\');
-
-			if (was_bslash)
+			if (i > 0 && line[i - prevlen] == '\\')
 				bslash_count++;
 			else
 				bslash_count = 0;
@@ -308,30 +270,24 @@ MainLoop(FILE *source)
 					in_quote = 0;
 			}
 
-			/* in extended comment? */
-			else if (in_xcomment)
-			{
-				if (line[i] == '*' && line[i + thislen] == '/')
-				{
-					if (xcdepth > 0)
-						xcdepth--;
-					else
+			/* start of extended comment? */
+			else if (line[i] == '/' && line[i + thislen] == '*')
 					{
-						in_xcomment = false;
+				in_xcomment++;
+				if (in_xcomment == 1) 
 						ADVANCE_1;
 					}
-				}
-				else if (line[i] == '/' && line[i + thislen] == '*')
-					xcdepth++;
-			}
 
-			/* start of extended comment? */
-			else if (line[i] == '/' && line[i + thislen] == '*')
+			/* end of extended comment? */
+			else if (line[i] == '*' && line[i + thislen] == '/')
 			{
-				xcdepth = 0;
-				in_xcomment = true;
+				in_xcomment--;
+				if (in_xcomment <= 0)
+				{
+					in_xcomment = 0;
 				ADVANCE_1;
 			}
+			}
 
 			/* start of quote? */
 			else if (line[i] == '\'' || line[i] == '"')
@@ -353,7 +309,7 @@ MainLoop(FILE *source)
 
 			/* colon -> substitute variable */
 			/* we need to be on the watch for the '::' operator */
-			else if (line[i] == ':' && !was_bslash
+			else if (line[i] == ':' && !bslash_count
 				  && strspn(line + i + thislen, VALID_VARIABLE_CHARS) > 0
 					 && !(prevlen > 0 && line[i - prevlen] == ':')
 				)
@@ -411,7 +367,7 @@ MainLoop(FILE *source)
 			}
 
 			/* semicolon? then send query */
-			else if (line[i] == ';' && !was_bslash && !paren_level)
+			else if (line[i] == ';' && !bslash_count && !paren_level)
 			{
 				line[i] = '\0';
 				/* is there anything else on the line? */
@@ -442,7 +398,7 @@ MainLoop(FILE *source)
 			 * if you have a burning need to send a semicolon or colon to
 			 * the backend ...
 			 */
-			else if (was_bslash && (line[i] == ';' || line[i] == ':'))
+			else if (bslash_count && (line[i] == ';' || line[i] == ':'))
 			{
 				/* remove the backslash */
 				memmove(line + i - prevlen, line + i, len - i + 1);
@@ -451,7 +407,7 @@ MainLoop(FILE *source)
 			}
 
 			/* backslash command */
-			else if (was_bslash)
+			else if (bslash_count)
 			{
 				const char *end_of_cmd = NULL;
 
@@ -499,15 +455,9 @@ MainLoop(FILE *source)
 					paren_level = 0;
 
 				/* process anything left after the backslash command */
-				i += end_of_cmd - &line[i];
+				i = end_of_cmd - line;
 				query_start = i;
 			}
-
-
-			/* stop the script after error */
-			if (!success && die_on_error)
-				break;
-
 		}						/* for (line) */
 
 
@@ -533,25 +483,19 @@ MainLoop(FILE *source)
 		if (query_buf->data[0] != '\0' && GetVariableBool(pset.vars, "SINGLELINE"))
 		{
 			success = SendQuery(query_buf->data);
-			slashCmdStatus = success ? CMD_SEND : CMD_ERROR;
+			slashCmdStatus = (success ? CMD_SEND : CMD_ERROR);
 			resetPQExpBuffer(previous_buf);
 			appendPQExpBufferStr(previous_buf, query_buf->data);
 			resetPQExpBuffer(query_buf);
 		}
 
-
-		if (!success && die_on_error && !pset.cur_cmd_interactive)
+		if (!pset.cur_cmd_interactive)
 		{
+			if (!success && die_on_error)
 			successResult = EXIT_USER;
-			break;
-		}
-
-
 		/* Have we lost the db connection? */
-		if (pset.db == NULL && !pset.cur_cmd_interactive)
-		{
+			else if (!pset.db)
 			successResult = EXIT_BADCONN;
-			break;
 		}
 	}							/* while !endoffile/session */
 

src/bin/psql/prompt.c

@@ -3,7 +3,7 @@
  *
  * Copyright 2000 by PostgreSQL Global Development Group
  *
- * $Header: /cvsroot/pgsql/src/bin/psql/prompt.c,v 1.22 2001/10/25 05:49:54 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/bin/psql/prompt.c,v 1.23 2003/03/20 06:43:35 momjian Exp $
  */
 #include "postgres_fe.h"
 #include "prompt.h"
@@ -69,17 +69,30 @@ get_prompt(promptStatus_t status)
 	char		buf[MAX_PROMPT_SIZE + 1];
 	bool		esc = false;
 	const char *p;
-	const char *prompt_string;
+	const char *prompt_string = "? ";
+	const char *prompt_name = NULL;
 
-	if (status == PROMPT_READY)
-		prompt_string = GetVariable(pset.vars, "PROMPT1");
-	else if (status == PROMPT_CONTINUE || status == PROMPT_SINGLEQUOTE || status == PROMPT_DOUBLEQUOTE || status == PROMPT_COMMENT || status == PROMPT_PAREN)
-		prompt_string = GetVariable(pset.vars, "PROMPT2");
-	else if (status == PROMPT_COPY)
-		prompt_string = GetVariable(pset.vars, "PROMPT3");
-	else
-		prompt_string = "? ";
+	switch (status)
+	{
+		case PROMPT_READY:
+			prompt_name = "PROMPT1";
+			break;
+
+		case PROMPT_CONTINUE:
+		case PROMPT_SINGLEQUOTE:
+		case PROMPT_DOUBLEQUOTE:
+		case PROMPT_COMMENT:
+		case PROMPT_PAREN:
+			prompt_name = "PROMPT2";
+			break;
+		
+		case PROMPT_COPY:
+			prompt_name = "PROMPT3";
+			break;
+	}
 
+	if (prompt_name)
+	  prompt_string = GetVariable(pset.vars, prompt_name);
 
 	destination[0] = '\0';
 
@@ -92,21 +105,15 @@ get_prompt(promptStatus_t status)
 		{
 			switch (*p)
 			{
-				case '%':
-					strcpy(buf, "%");
-					break;
-
 					/* Current database */
 				case '/':
 					if (pset.db)
 						strncpy(buf, PQdb(pset.db), MAX_PROMPT_SIZE);
 					break;
 				case '~':
-					{
-						const char *var;
-
 						if (pset.db)
 						{
+						const char *var;
 							if (strcmp(PQdb(pset.db), PQuser(pset.db)) == 0 ||
 								((var = getenv("PGDATABASE")) && strcmp(var, PQdb(pset.db)) == 0))
 								strcpy(buf, "~");
@@ -114,7 +121,7 @@ get_prompt(promptStatus_t status)
 								strncpy(buf, PQdb(pset.db), MAX_PROMPT_SIZE);
 						}
 						break;
-					}
+
 					/* DB server hostname (long/short) */
 				case 'M':
 				case 'm':
@@ -164,15 +171,8 @@ get_prompt(promptStatus_t status)
 				case '7':
 				case '8':
 				case '9':
-					{
-						long int	l;
-						char	   *end;
-
-						l = strtol(p, &end, 0);
-						sprintf(buf, "%c", (unsigned char) l);
-						p = end - 1;
+					*buf = parse_char(&p);
 						break;
-					}
 
 				case 'R':
 					switch (status)

src/bin/psql/startup.c

@@ -3,7 +3,7 @@
  *
  * Copyright 2000 by PostgreSQL Global Development Group
  *
- * $Header: /cvsroot/pgsql/src/bin/psql/startup.c,v 1.71 2003/03/18 22:15:44 petere Exp $
+ * $Header: /cvsroot/pgsql/src/bin/psql/startup.c,v 1.72 2003/03/20 06:43:35 momjian Exp $
  */
 #include "postgres_fe.h"
 
@@ -253,10 +253,9 @@ main(int argc, char *argv[])
 	 */
 	else if (options.action == ACT_SINGLE_SLASH)
 	{
-		const char *value;
-
-		if ((value = GetVariable(pset.vars, "ECHO")) && strcmp(value, "all") == 0)
+		if (VariableEquals(pset.vars, "ECHO", "all"))
 			puts(options.action_string);
+
 		successResult = HandleSlashCmds(options.action_string, NULL, NULL, NULL) != CMD_ERROR
 			? EXIT_SUCCESS : EXIT_FAILURE;
 	}
@@ -266,10 +265,9 @@ main(int argc, char *argv[])
 	 */
 	else if (options.action == ACT_SINGLE_QUERY)
 	{
-		const char *value;
-
-		if ((value = GetVariable(pset.vars, "ECHO")) && strcmp(value, "all") == 0)
+		if (VariableEquals(pset.vars, "ECHO", "all"))
 			puts(options.action_string);
+
 		successResult = SendQuery(options.action_string)
 			? EXIT_SUCCESS : EXIT_FAILURE;
 	}

src/bin/psql/variables.c

@@ -3,7 +3,7 @@
  *
  * Copyright 2000 by PostgreSQL Global Development Group
  *
- * $Header: /cvsroot/pgsql/src/bin/psql/variables.c,v 1.9 2001/02/10 02:31:28 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/bin/psql/variables.c,v 1.10 2003/03/20 06:43:35 momjian Exp $
  */
 #include "postgres_fe.h"
 #include "variables.h"
@@ -68,6 +68,74 @@ GetVariableBool(VariableSpace space, const char *name)
 }
 
 
+bool
+VariableEquals(VariableSpace space, const char name[], const char value[])
+{
+	const char *var;
+	var = GetVariable(space, name);
+	return var && (strcmp(var, value) == 0);
+}
+
+
+int 
+GetVariableNum(VariableSpace space, 
+	 				const char name[], 
+					int defaultval,
+					int faultval,
+					bool allowtrail)
+{
+	const char *var;
+	int result;
+
+	var = GetVariable(space, name);
+	if (!var)
+	  result = defaultval;
+	else if (!var[0])
+	  result = faultval;
+	else
+	{
+		char *end;
+		result = strtol(var, &end, 0);
+		if (!allowtrail && *end)
+		  result = faultval;
+	}
+
+	return result;
+}
+
+
+int
+SwitchVariable(VariableSpace space, const char name[], const char *opt, ...)
+{
+	int result;
+	const char *var;
+
+	var = GetVariable(space, name);
+	if (var) 
+	{
+		va_list args;
+		va_start(args, opt);
+		for (result=1; opt && (strcmp(var, opt) != 0); result++)
+			opt = va_arg(args,const char *);
+
+		if (!opt) result = var_notfound;
+		va_end(args);
+	}
+	else
+	  result = var_notset;
+
+	return result;
+}
+
+
+void 
+PrintVariables(VariableSpace space)
+{
+  struct _variable *ptr;
+  for (ptr = space->next; ptr; ptr = ptr->next)
+	 printf("%s = '%s'\n", ptr->name, ptr->value);
+}
+
 
 bool
 SetVariable(VariableSpace space, const char *name, const char *value)

src/bin/psql/variables.h

@@ -3,7 +3,7 @@
  *
  * Copyright 2000 by PostgreSQL Global Development Group
  *
- * $Header: /cvsroot/pgsql/src/bin/psql/variables.h,v 1.10 2001/11/05 17:46:31 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/bin/psql/variables.h,v 1.11 2003/03/20 06:43:35 momjian Exp $
  */
 
 /*
@@ -30,10 +30,33 @@ typedef struct _variable *VariableSpace;
 
 VariableSpace CreateVariableSpace(void);
 const char *GetVariable(VariableSpace space, const char *name);
-bool		GetVariableBool(VariableSpace space, const char *name);
-bool		SetVariable(VariableSpace space, const char *name, const char *value);
-bool		SetVariableBool(VariableSpace space, const char *name);
-bool		DeleteVariable(VariableSpace space, const char *name);
-void		DestroyVariableSpace(VariableSpace space);
+bool	GetVariableBool(VariableSpace space, const char *name);
+bool	VariableEquals(VariableSpace space, const char name[], const char *opt);
+
+/* Read numeric variable, or defaultval if it is not set, or faultval if its
+ * value is not a valid numeric string.  If allowtrail is false, this will 
+ * include the case where there are trailing characters after the number.
+ */
+int GetVariableNum(VariableSpace space, 
+	 					const char name[], 
+						int defaultval, 
+						int faultval,
+						bool allowtrail);
+
+
+/* Find value of variable <name> among NULL-terminated list of alternative 
+ * options.  Returns var_notset if the variable was not set, var_notfound if its
+ * value did not occur in the list of options, or the number of the matching
+ * option.  The first option is 1, the second is 2 and so on.
+ */
+enum { var_notset = 0, var_notfound = -1 };
+int 	SwitchVariable(VariableSpace space, const char name[], const char *opt,...);
+
+void 	PrintVariables(VariableSpace space);
+
+bool	SetVariable(VariableSpace space, const char *name, const char *value);
+bool	SetVariableBool(VariableSpace space, const char *name);
+bool	DeleteVariable(VariableSpace space, const char *name);
+void	DestroyVariableSpace(VariableSpace space);
 
 #endif   /* VARIABLES_H */