From 029c5ac03db72f1898ee17e417650a2e0764b239 Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <peter@eisentraut.org>
Date: Fri, 16 Apr 2021 11:46:01 +0200
Subject: [PATCH] psql: Refine lexing of BEGIN...END blocks in CREATE FUNCTION
statements
Only track BEGIN...END blocks if they are in a CREATE [OR REPLACE]
{FUNCTION|PROCEDURE} statement. Ignore if in parentheses.
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Discussion: https://www.postgresql.org/message-id/cee01d26fe55bc086b3bcf10bfe4e8d450e2f608.camel@cybertec.at
---
src/fe_utils/psqlscan.l | 53 ++++++++++++++++++++++++-----
src/include/fe_utils/psqlscan_int.h | 8 ++++-
2 files changed, 52 insertions(+), 9 deletions(-)
diff --git a/src/fe_utils/psqlscan.l b/src/fe_utils/psqlscan.l
index 4ec57e96a9d..991b7de0b55 100644
--- a/src/fe_utils/psqlscan.l
+++ b/src/fe_utils/psqlscan.l
@@ -870,18 +870,55 @@ other .
{identifier} {
+ /*
+ * We need to track if we are inside a BEGIN .. END block
+ * in a function definition, so that semicolons contained
+ * therein don't terminate the whole statement. Short of
+ * writing a full parser here, the following heuristic
+ * should work. First, we track whether the beginning of
+ * the statement matches CREATE [OR REPLACE]
+ * {FUNCTION|PROCEDURE}
+ */
+
+ if (cur_state->identifier_count == 0)
+ memset(cur_state->identifiers, 0, sizeof(cur_state->identifiers));
+
+ if (pg_strcasecmp(yytext, "create") == 0 ||
+ pg_strcasecmp(yytext, "function") == 0 ||
+ pg_strcasecmp(yytext, "procedure") == 0 ||
+ pg_strcasecmp(yytext, "or") == 0 ||
+ pg_strcasecmp(yytext, "replace") == 0)
+ {
+ if (cur_state->identifier_count < sizeof(cur_state->identifiers))
+ cur_state->identifiers[cur_state->identifier_count] = pg_tolower((unsigned char) yytext[0]);
+ }
+
cur_state->identifier_count++;
- if (pg_strcasecmp(yytext, "begin") == 0
- || pg_strcasecmp(yytext, "case") == 0)
+
+ if (cur_state->identifiers[0] == 'c' &&
+ (cur_state->identifiers[1] == 'f' || cur_state->identifiers[1] == 'p' ||
+ (cur_state->identifiers[1] == 'o' && cur_state->identifiers[2] == 'r' &&
+ (cur_state->identifiers[3] == 'f' || cur_state->identifiers[3] == 'p'))) &&
+ cur_state->paren_depth == 0)
{
- if (cur_state->identifier_count > 1)
+ if (pg_strcasecmp(yytext, "begin") == 0)
cur_state->begin_depth++;
+ else if (pg_strcasecmp(yytext, "case") == 0)
+ {
+ /*
+ * CASE also ends with END. We only need to track
+ * this if we are already inside a BEGIN.
+ */
+ if (cur_state->begin_depth >= 1)
+ cur_state->begin_depth++;
+ }
+ else if (pg_strcasecmp(yytext, "end") == 0)
+ {
+ if (cur_state->begin_depth > 0)
+ cur_state->begin_depth--;
+ }
}
- else if (pg_strcasecmp(yytext, "end") == 0)
- {
- if (cur_state->begin_depth > 0)
- cur_state->begin_depth--;
- }
+
ECHO;
}
diff --git a/src/include/fe_utils/psqlscan_int.h b/src/include/fe_utils/psqlscan_int.h
index 91d7d4d5c6c..8ada9770927 100644
--- a/src/include/fe_utils/psqlscan_int.h
+++ b/src/include/fe_utils/psqlscan_int.h
@@ -114,8 +114,14 @@ typedef struct PsqlScanStateData
int paren_depth; /* depth of nesting in parentheses */
int xcdepth; /* depth of nesting in slash-star comments */
char *dolqstart; /* current $foo$ quote start string */
+
+ /*
+ * State to track boundaries of BEGIN ... END blocks in function
+ * definitions, so that semicolons do not send query too early.
+ */
int identifier_count; /* identifiers since start of statement */
- int begin_depth; /* depth of begin/end routine body blocks */
+ char identifiers[4]; /* records the first few identifiers */
+ int begin_depth; /* depth of begin/end pairs */
/*
* Callback functions provided by the program making use of the lexer,