From de94ed89d5b013acf9729ac04e52166bbb8ca736 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Sun, 24 Feb 2019 12:51:50 -0500 Subject: [PATCH] Fix ecpg bugs caused by missing semicolons in the backend grammar. The Bison documentation clearly states that a semicolon is required after every grammar rule, and our scripts that generate ecpg's grammar from the backend's implicitly assumed this is true. But it turns out that only ancient versions of Bison actually enforce that. There have been a couple of rules without trailing semicolons in gram.y for some time, and as a consequence, ecpg's grammar was faulty and produced wrong output for the affected statements. To fix, add the missing semis, and add some cross-checks to ecpg's scripts so that they'll bleat if we mess this up again. The cases that were broken were: * "SET variable = DEFAULT" (but not "SET variable TO DEFAULT"), as well as allied syntaxes such as ALTER SYSTEM SET ... DEFAULT. These produced syntactically invalid output that the server would reject. * Multiple type names in DROP TYPE/DOMAIN commands. Only the first type name would be listed in the emitted command. Per report from Daisuke Higuchi. Back-patch to all supported versions. Discussion: https://postgr.es/m/1803D792815FC24D871C00D17AE95905DB51CE@g01jpexmbkw24 --- src/backend/parser/gram.y | 2 ++ src/interfaces/ecpg/preproc/check_rules.pl | 12 ++++++++++-- src/interfaces/ecpg/preproc/parse.pl | 7 +++++++ 3 files changed, 19 insertions(+), 2 deletions(-) diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y index 9d652a3e10..bc65319c2c 100644 --- a/src/backend/parser/gram.y +++ b/src/backend/parser/gram.y @@ -1467,6 +1467,7 @@ generic_set: n->name = $1; $$ = n; } + ; set_rest_more: /* Generic SET syntaxes: */ generic_set {$$ = $1;} @@ -6375,6 +6376,7 @@ attrs: '.' attr_name type_name_list: Typename { $$ = list_make1($1); } | type_name_list ',' Typename { $$ = lappend($1, $3); } + ; /***************************************************************************** * diff --git a/src/interfaces/ecpg/preproc/check_rules.pl b/src/interfaces/ecpg/preproc/check_rules.pl index 6c8b004854..c6a183ec71 100644 --- a/src/interfaces/ecpg/preproc/check_rules.pl +++ b/src/interfaces/ecpg/preproc/check_rules.pl @@ -1,7 +1,7 @@ #!/usr/bin/perl # src/interfaces/ecpg/preproc/check_rules.pl -# test parser generater for ecpg -# call with backend parser as stdin +# test parser generator for ecpg +# call with backend grammar as stdin # # Copyright (c) 2009-2018, PostgreSQL Global Development Group # @@ -47,6 +47,7 @@ my %replace_line = ( my $block = ''; my $yaccmode = 0; +my $in_rule = 0; my $brace_indent = 0; my (@arr, %found); my $comment = 0; @@ -131,10 +132,14 @@ while (<$parser_fh>) $found{$block} = 1; $cc++; $block = ''; + $in_rule = 0 if $arr[$fieldIndexer] eq ';'; } elsif (($arr[$fieldIndexer] =~ '[A-Za-z0-9]+:') || $arr[ $fieldIndexer + 1 ] eq ':') { + die "unterminated rule at grammar line $.\n" + if $in_rule; + $in_rule = 1; $non_term_id = $arr[$fieldIndexer]; $non_term_id =~ tr/://d; } @@ -145,6 +150,9 @@ while (<$parser_fh>) } } +die "unterminated rule at end of grammar\n" + if $in_rule; + close $parser_fh; if ($verbose) { diff --git a/src/interfaces/ecpg/preproc/parse.pl b/src/interfaces/ecpg/preproc/parse.pl index ad87aad283..863d770e10 100644 --- a/src/interfaces/ecpg/preproc/parse.pl +++ b/src/interfaces/ecpg/preproc/parse.pl @@ -22,6 +22,7 @@ $path = "." unless $path; my $copymode = 0; my $brace_indent = 0; my $yaccmode = 0; +my $in_rule = 0; my $header_included = 0; my $feature_not_supported = 0; my $tokenmode = 0; @@ -288,6 +289,7 @@ sub main @fields = (); $infield = 0; $line = ''; + $in_rule = 0; next; } @@ -365,6 +367,9 @@ sub main $line = ''; @fields = (); $infield = 1; + die "unterminated rule at grammar line $.\n" + if $in_rule; + $in_rule = 1; next; } elsif ($copymode) @@ -415,6 +420,8 @@ sub main } } } + die "unterminated rule at end of grammar\n" + if $in_rule; return; }