From 9211fb6e2de425ff9b4669c6c6f6fabea7c3f639 Mon Sep 17 00:00:00 2001
From: John Naylor <jcnaylor@gmail.com>
Date: Sun, 30 Sep 2018 13:08:25 +0700
Subject: [PATCH v1 3/4] Use start condition scopes in the core, psql, and ECPG
 scanners.

This makes it easier to diff the core scanner with the ECPG scanner.
---
 src/backend/parser/scan.l         |  12 ++-
 src/fe_utils/psqlscan.l           |   8 +-
 src/interfaces/ecpg/preproc/pgc.l | 133 +++++++++++++++++++++---------
 3 files changed, 107 insertions(+), 46 deletions(-)

diff --git a/src/backend/parser/scan.l b/src/backend/parser/scan.l
index a2454732a1..f20a6e58fe 100644
--- a/src/backend/parser/scan.l
+++ b/src/backend/parser/scan.l
@@ -430,19 +430,23 @@ other			.
 						(yyextra->xcdepth)--;
 				}
 
-<xc>{xcinside}	{
+<xc>{
+{xcinside}		{
 					/* ignore */
 				}
 
-<xc>{op_chars}	{
+{op_chars}		{
 					/* ignore */
 				}
 
-<xc>\*+			{
+\*+				{
 					/* ignore */
 				}
 
-<xc><<EOF>>		{ yyerror("unterminated /* comment"); }
+<<EOF>>			{
+					yyerror("unterminated /* comment");
+				}
+} /* <xc> */
 
 {xbstart}		{
 					/* Binary bit type.
diff --git a/src/fe_utils/psqlscan.l b/src/fe_utils/psqlscan.l
index 25253b54ea..eb239685d5 100644
--- a/src/fe_utils/psqlscan.l
+++ b/src/fe_utils/psqlscan.l
@@ -417,17 +417,19 @@ other			.
 					ECHO;
 				}
 
-<xc>{xcinside}	{
+<xc>{
+{xcinside}		{
 					ECHO;
 				}
 
-<xc>{op_chars}	{
+{op_chars}		{
 					ECHO;
 				}
 
-<xc>\*+			{
+\*+				{
 					ECHO;
 				}
+} /* <xc> */
 
 {xbstart}		{
 					BEGIN(xb);
diff --git a/src/interfaces/ecpg/preproc/pgc.l b/src/interfaces/ecpg/preproc/pgc.l
index 421c62339b..16b1c1bb08 100644
--- a/src/interfaces/ecpg/preproc/pgc.l
+++ b/src/interfaces/ecpg/preproc/pgc.l
@@ -395,11 +395,11 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
 		token_start = NULL;
 %}
 
-<SQL>{whitespace}	{
+<SQL>{
+{whitespace}	{
 					/* ignore */
 				}
-
-<SQL>{xcstart}		{
+{xcstart}		{
 					token_start = yytext;
 					state_before = YYSTATE;
 					xcdepth = 0;
@@ -408,7 +408,9 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
 					yyless(2);
 					fputs("/*", yyout);
 				}
-<C>{xcstart}		{
+} /* <SQL> */
+
+<C>{xcstart}	{
 					token_start = yytext;
 					state_before = YYSTATE;
 					xcdepth = 0;
@@ -443,24 +445,30 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
 					token_start = NULL;
 				}
 
-<xcc,xcsql>{xcinside}	{
+<xcc,xcsql>{
+{xcinside}		{
 					ECHO;
 				}
-<xcc,xcsql>{op_chars}	{
+{op_chars}		{
 					ECHO;
 				}
-<xcc,xcsql>\*+	{
+\*+				{
 					ECHO;
 				}
+<<EOF>>			{
+					mmfatal(PARSE_ERROR, "unterminated /* comment");
+				}
+} /* <xcc,xcsql> */
 
-<xcc,xcsql><<EOF>>		{ mmfatal(PARSE_ERROR, "unterminated /* comment"); }
-
-<SQL>{xbstart}	{
+<SQL>{
+{xbstart}		{
 					token_start = yytext;
 					BEGIN(xb);
 					startlit();
 					addlitchar('b');
 				}
+} /* <SQL> */
+
 <xb>{quotestop}	|
 <xb>{quotefail} {
 					yyless(1);
@@ -502,7 +510,9 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
 					BEGIN(xqc);
 					startlit();
 				}
-<SQL>{xnstart} {
+
+<SQL>{
+{xnstart}		{
 					/* National character.
 					 * Transfer it as-is to the backend.
 					 */
@@ -511,25 +521,27 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
 					BEGIN(xn);
 					startlit();
 				}
-<SQL>{xqstart}	{
+{xqstart}		{
 					token_start = yytext;
 					state_before = YYSTATE;
 					BEGIN(xq);
 					startlit();
 				}
-<SQL>{xestart}	{
+{xestart}		{
 					token_start = yytext;
 					state_before = YYSTATE;
 					BEGIN(xe);
 					startlit();
 				}
-<SQL>{xusstart}	{
+{xusstart}		{
 					token_start = yytext;
 					state_before = YYSTATE;
 					BEGIN(xus);
 					startlit();
 					addlit(yytext, yyleng);
 				}
+} /* <SQL> */
+
 <xq,xqc>{quotestop} |
 <xq,xqc>{quotefail} {
 					yyless(1);
@@ -584,13 +596,15 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
 					addlitchar(yytext[0]);
 				}
 <xq,xqc,xe,xn,xus><<EOF>>	{ mmfatal(PARSE_ERROR, "unterminated quoted string"); }
-<SQL>{dolqfailed}	{
+
+<SQL>{
+{dolqfailed}	{
 					/* throw back all but the initial "$" */
 					yyless(1);
 					/* and treat it as {other} */
 					return yytext[0];
 				}
-<SQL>{dolqdelim} {
+{dolqdelim}		{
 					token_start = yytext;
 					if (dolqstart)
 						free(dolqstart);
@@ -599,6 +613,8 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
 					startlit();
 					addlit(yytext, yyleng);
 				}
+} /* <SQL> */
+
 <xdolq>{dolqdelim} {
 					if (strcmp(yytext, dolqstart) == 0)
 					{
@@ -631,17 +647,21 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
 					addlitchar(yytext[0]);
 				}
 <xdolq><<EOF>>	{ base_yyerror("unterminated dollar-quoted string"); }
-<SQL>{xdstart}	{
+
+<SQL>{
+{xdstart}		{
 					state_before = YYSTATE;
 					BEGIN(xd);
 					startlit();
 				}
-<SQL>{xuistart}	{
+{xuistart}		{
 					state_before = YYSTATE;
 					BEGIN(xui);
 					startlit();
 					addlit(yytext, yyleng);
 				}
+} /* <SQL> */
+
 <xd>{xdstop}	{
 					BEGIN(state_before);
 					if (literallen == 0)
@@ -677,15 +697,43 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
 					startlit();
 				}
 <xdc>{xdcinside}	{ addlit(yytext, yyleng); }
-<SQL>{typecast}		{ return TYPECAST; }
-<SQL>{dot_dot}		{ return DOT_DOT; }
-<SQL>{colon_equals}	{ return COLON_EQUALS; }
-<SQL>{equals_greater} { return EQUALS_GREATER; }
-<SQL>{less_equals}	{ return LESS_EQUALS; }
-<SQL>{greater_equals} { return GREATER_EQUALS; }
-<SQL>{less_greater}	{ return NOT_EQUALS; }
-<SQL>{not_equals}	{ return NOT_EQUALS; }
-<SQL>{informix_special}	{
+
+<SQL>{
+{typecast}		{
+					return TYPECAST;
+				}
+
+{dot_dot}		{
+					return DOT_DOT;
+				}
+
+{colon_equals}	{
+					return COLON_EQUALS;
+				}
+
+{equals_greater} {
+					return EQUALS_GREATER;
+				}
+
+{less_equals}	{
+					return LESS_EQUALS;
+				}
+
+{greater_equals} {
+					return GREATER_EQUALS;
+				}
+
+{less_greater}	{
+					/* We accept both "<>" and "!=" as meaning NOT_EQUALS */
+					return NOT_EQUALS;
+				}
+
+{not_equals}	{
+					/* We accept both "<>" and "!=" as meaning NOT_EQUALS */
+					return NOT_EQUALS;
+				}
+
+{informix_special}	{
 			  /* are we simulating Informix? */
 				if (INFORMIX_MODE)
 				{
@@ -694,7 +742,7 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
 				else
 					return yytext[0];
 				}
-<SQL>{self}		{
+{self}			{
 					/*
 					 * We may find a ';' inside a structure
 					 * definition in a TYPE or VAR statement.
@@ -704,7 +752,7 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
 						BEGIN(C);
 					return yytext[0];
 				}
-<SQL>{operator}	{
+{operator}		{
 					/*
 					 * Check for embedded slash-star or dash-dash; those
 					 * are comment starts, so operator must stop there.
@@ -800,15 +848,18 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
 					base_yylval.str = mm_strdup(yytext);
 					return Op;
 				}
-<SQL>{param}	{
+{param}			{
 					base_yylval.ival = atol(yytext+1);
 					return PARAM;
 				}
-<SQL>{ip}		{
+{ip}			{
 					base_yylval.str = mm_strdup(yytext);
 					return IP;
 				}
-<C,SQL>{integer}	{
+}  /* <SQL> */
+
+<C,SQL>{
+{integer}		{
 					int val;
 					char* endptr;
 
@@ -823,29 +874,32 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
 					base_yylval.ival = val;
 					return ICONST;
 				}
-<C,SQL>{decimal}	{
+{decimal}		{
 					base_yylval.str = mm_strdup(yytext);
 					return FCONST;
 				}
-<C,SQL>{real}	{
+{real}			{
 						base_yylval.str = mm_strdup(yytext);
 						return FCONST;
 				}
-<SQL>{realfail1}	{
+} /* <C,SQL> */
+
+<SQL>{
+{realfail1}		{
 					yyless(yyleng-1);
 					base_yylval.str = mm_strdup(yytext);
 					return FCONST;
 				}
-<SQL>{realfail2}	{
+{realfail2}		{
 					yyless(yyleng-2);
 					base_yylval.str = mm_strdup(yytext);
 					return FCONST;
 				}
-<SQL>:{identifier}((("->"|\.){identifier})|(\[{array}\]))*	{
+:{identifier}((("->"|\.){identifier})|(\[{array}\]))*	{
 					base_yylval.str = mm_strdup(yytext+1);
 					return CVARIABLE;
 				}
-<SQL>{identifier}	{
+{identifier}	{
 					const ScanKeyword  *keyword;
 
 					if (!isdefine())
@@ -873,9 +927,10 @@ cppline			{space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
 					}
 				}
 
-<SQL>{other}	{
+{other}			{
 					return yytext[0];
 				}
+} /* <SQL> */
 
 <C>{exec_sql}		{ BEGIN(SQL); return SQL_START; }
 <C>{informix_special}	{
-- 
2.17.1