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

1 files changed, 45 insertions, 101 deletions

diff --git a/src/bin/psql/mainloop.c b/src/bin/psql/mainloop.c
index e9ed1a621e5..27b5a560d5f 100644
--- a/src/bin/psql/mainloop.c
+++ b/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 */