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bmomjianbmomjian
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Enable standard_conforming_strings to be turned on.
Kevin Grittner
1 parent a9c1047 commit 19c21d1

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11 files changed

+294
-112
lines changed

11 files changed

+294
-112
lines changed

‎doc/src/sgml/config.sgml

Lines changed: 22 additions & 26 deletions
Original file line numberDiff line numberDiff line change
@@ -1,5 +1,5 @@
11
<!--
2-
$PostgreSQL: pgsql/doc/src/sgml/config.sgml,v 1.49 2006/03/04 22:19:31 tgl Exp $
2+
$PostgreSQL: pgsql/doc/src/sgml/config.sgml,v 1.50 2006/03/06 19:49:19 momjian Exp $
33
-->
44
<chapter Id="runtime-config">
55
<title>Server Configuration</title>
@@ -3737,10 +3737,28 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir'
37373737
</para>
37383738
<para>
37393739
Escape string syntax (<literal>E'...'</>) should be used for
3740-
escapes, because in future versions of
3741-
<productname>PostgreSQL</productname> ordinary strings will have
3740+
backslash escape sequences, because ordinary strings have
37423741
the standard-conforming behavior of treating backslashes
3743-
literally.
3742+
literally when the <literal>standard-conforming-strings</>
3743+
option is set <literal>on</>.
3744+
</para>
3745+
</listitem>
3746+
</varlistentry>
3747+
3748+
<varlistentry id="guc-standard-conforming-strings" xreflabel="standard_conforming_strings">
3749+
<term><varname>standard_conforming_strings</varname> (<type>boolean</type>)</term>
3750+
<indexterm><primary>strings</><secondary>escape</></>
3751+
<indexterm>
3752+
<primary><varname>standard_conforming_strings</> configuration parameter</primary>
3753+
</indexterm>
3754+
<listitem>
3755+
<para>
3756+
Controls whether ordinary string literals
3757+
(<literal>'...'</>) treat backslashes literally, as specified in
3758+
the SQL standard. Applications may check this
3759+
parameter to determine how string literals will be processed.
3760+
The presence of this parameter can also be taken as an indication
3761+
that the escape string syntax (<literal>E'...'</>) is supported.
37443762
</para>
37453763
</listitem>
37463764
</varlistentry>
@@ -3992,28 +4010,6 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir'
39924010
</listitem>
39934011
</varlistentry>
39944012

3995-
<varlistentry id="guc-standard-conforming-strings" xreflabel="standard_conforming_strings">
3996-
<term><varname>standard_conforming_strings</varname> (<type>boolean</type>)</term>
3997-
<indexterm><primary>strings</><secondary>escape</></>
3998-
<indexterm>
3999-
<primary><varname>standard_conforming_strings</> configuration parameter</primary>
4000-
</indexterm>
4001-
<listitem>
4002-
<para>
4003-
Reports whether ordinary string literals
4004-
(<literal>'...'</>) treat backslashes literally, as specified in
4005-
the SQL standard. The value is currently always <literal>off</>,
4006-
indicating that backslashes are treated as escapes. It is planned
4007-
that this will change to <literal>on</> in a future
4008-
<productname>PostgreSQL</productname> release when string literal
4009-
syntax changes to meet the standard. Applications may check this
4010-
parameter to determine how string literals will be processed.
4011-
The presence of this parameter can also be taken as an indication
4012-
that the escape string syntax (<literal>E'...'</>) is supported.
4013-
</para>
4014-
</listitem>
4015-
</varlistentry>
4016-
40174013
</variablelist>
40184014
</sect1>
40194015

‎src/backend/parser/scan.l

Lines changed: 61 additions & 39 deletions
Original file line numberDiff line numberDiff line change
@@ -24,7 +24,7 @@
2424
* Portions Copyright (c) 1994, Regents of the University of California
2525
*
2626
* IDENTIFICATION
27-
* $PostgreSQL: pgsql/src/backend/parser/scan.l,v 1.130 2006/03/05 15:58:34 momjian Exp $
27+
* $PostgreSQL: pgsql/src/backend/parser/scan.l,v 1.131 2006/03/06 19:49:20 momjian Exp $
2828
*
2929
*-------------------------------------------------------------------------
3030
*/
@@ -51,13 +51,14 @@ static int xcdepth = 0; /* depth of nesting in slash-star comments */
5151
static char *dolqstart; /* current $foo$ quote start string */
5252

5353
/*
54-
* GUC variable. This is a DIRECT violation of the warning given at the
54+
* GUC variables. This is a DIRECT violation of the warning given at the
5555
* head of gram.y, ie flex/bison code must not depend on any GUC variables;
5656
* as such, changing its value can induce very unintuitive behavior.
5757
* But we shall have to live with it as a short-term thing until the switch
5858
* to SQL-standard string syntax is complete.
5959
*/
6060
bool escape_string_warning;
61+
bool standard_conforming_strings;
6162

6263
static bool warn_on_first_escape;
6364

@@ -77,6 +78,7 @@ static void addlitchar(unsigned char ychar);
7778
static char *litbufdup(void);
7879
static int pg_err_position(void);
7980
static void check_escape_warning(void);
81+
static void check_string_escape_warning(unsigned char ychar);
8082

8183
/*
8284
* When we parse a token that requires multiple lexer rules to process,
@@ -119,14 +121,16 @@ static unsigned char unescape_single_char(unsigned char c);
119121
* <xc> extended C-style comments
120122
* <xd> delimited identifiers (double-quoted identifiers)
121123
* <xh> hexadecimal numeric string
122-
* <xq> quoted strings
124+
* <xq> standard quoted strings
125+
* <xe> extended quoted strings (support backslash escape sequences)
123126
* <xdolq> $foo$ quoted strings
124127
*/
125128

126129
%x xb
127130
%x xc
128131
%x xd
129132
%x xh
133+
%x xe
130134
%x xq
131135
%x xdolq
132136

@@ -200,16 +204,18 @@ xnstart [nN]{quote}
200204

201205
/* Quoted string that allows backslash escapes */
202206
xestart [eE]{quote}
207+
xeinside [^\\']+
208+
xeescape [\\][^0-7]
209+
xeoctesc [\\][0-7]{1,3}
210+
xehexesc [\\]x[0-9A-Fa-f]{1,2}
203211

204212
/* Extended quote
205213
* xqdouble implements embedded quote, ''''
206214
*/
207215
xqstart {quote}
208216
xqdouble {quote}{quote}
209217
xqinside [^\\']+
210-
xqescape [\\][^0-7]
211-
xqoctesc [\\][0-7]{1,3}
212-
xqhexesc [\\]x[0-9A-Fa-f]{1,2}
218+
xqbackslash [\\]
213219

214220
/* $foo$ style quotes ("dollar quoting")
215221
* The quoted string starts with $foo$ where "foo" is an optional string
@@ -428,73 +434,62 @@ other .
428434
{xqstart} {
429435
warn_on_first_escape = true;
430436
token_start = yytext;
431-
BEGIN(xq);
437+
if (standard_conforming_strings)
438+
BEGIN(xq);
439+
else
440+
BEGIN(xe);
432441
startlit();
433442
}
434443
{xestart} {
435444
warn_on_first_escape = false;
436445
token_start = yytext;
437-
BEGIN(xq);
446+
BEGIN(xe);
438447
startlit();
439448
}
440-
<xq>{quotestop} |
441-
<xq>{quotefail} {
449+
<xq,xe>{quotestop} |
450+
<xq,xe>{quotefail} {
442451
yyless(1);
443452
BEGIN(INITIAL);
444453
yylval.str = litbufdup();
445454
return SCONST;
446455
}
447-
<xq>{xqdouble} {
456+
<xq,xe>{xqdouble} {
448457
addlitchar('\'');
449458
}
450459
<xq>{xqinside} {
451460
addlit(yytext, yyleng);
452461
}
453-
<xq>{xqescape} {
454-
if (yytext[1] == '\'')
455-
{
456-
if (warn_on_first_escape && escape_string_warning)
457-
ereport(WARNING,
458-
(errcode(ERRCODE_NONSTANDARD_USE_OF_ESCAPE_CHARACTER),
459-
errmsg("nonstandard use of \\' in a string literal"),
460-
errhint("Use '' to write quotes in strings, or use the escape string syntax (E'...')."),
461-
errposition(pg_err_position())));
462-
warn_on_first_escape = false; /* warn only once per string */
463-
}
464-
else if (yytext[1] == '\\')
465-
{
466-
if (warn_on_first_escape && escape_string_warning)
467-
ereport(WARNING,
468-
(errcode(ERRCODE_NONSTANDARD_USE_OF_ESCAPE_CHARACTER),
469-
errmsg("nonstandard use of \\\\ in a string literal"),
470-
errhint("Use the escape string syntax for backslashes, e.g., E'\\\\'."),
471-
errposition(pg_err_position())));
472-
warn_on_first_escape = false; /* warn only once per string */
473-
}
474-
else
475-
check_escape_warning();
462+
<xe>{xeinside} {
463+
addlit(yytext, yyleng);
464+
}
465+
<xq>{xqbackslash} {
466+
check_string_escape_warning(yytext[1]);
467+
addlitchar('\\');
468+
}
469+
<xe>{xeescape} {
470+
check_string_escape_warning(yytext[1]);
476471
addlitchar(unescape_single_char(yytext[1]));
477472
}
478-
<xq>{xqoctesc} {
473+
<xe>{xeoctesc} {
479474
unsigned char c = strtoul(yytext+1, NULL, 8);
480475

481476
check_escape_warning();
482477
addlitchar(c);
483478
}
484-
<xq>{xqhexesc} {
479+
<xe>{xehexesc} {
485480
unsigned char c = strtoul(yytext+2, NULL, 16);
486481

487482
check_escape_warning();
488483
addlitchar(c);
489484
}
490-
<xq>{quotecontinue} {
485+
<xq,xe>{quotecontinue} {
491486
/* ignore */
492487
}
493-
<xq>. {
488+
<xe>. {
494489
/* This is only needed for \ just before EOF */
495490
addlitchar(yytext[0]);
496491
}
497-
<xq><<EOF>> { yyerror("unterminated quoted string"); }
492+
<xq,xe><<EOF>> { yyerror("unterminated quoted string"); }
498493

499494
{dolqdelim} {
500495
token_start = yytext;
@@ -875,6 +870,33 @@ unescape_single_char(unsigned char c)
875870
}
876871
}
877872

873+
static void
874+
check_string_escape_warning(unsigned char ychar)
875+
{
876+
if (ychar == '\'')
877+
{
878+
if (warn_on_first_escape && escape_string_warning)
879+
ereport(WARNING,
880+
(errcode(ERRCODE_NONSTANDARD_USE_OF_ESCAPE_CHARACTER),
881+
errmsg("nonstandard use of \\' in a string literal"),
882+
errhint("Use '' to write quotes in strings, or use the escape string syntax (E'...')."),
883+
errposition(pg_err_position())));
884+
warn_on_first_escape = false; /* warn only once per string */
885+
}
886+
else if (ychar == '\\')
887+
{
888+
if (warn_on_first_escape && escape_string_warning)
889+
ereport(WARNING,
890+
(errcode(ERRCODE_NONSTANDARD_USE_OF_ESCAPE_CHARACTER),
891+
errmsg("nonstandard use of \\\\ in a string literal"),
892+
errhint("Use the escape string syntax for backslashes, e.g., E'\\\\'."),
893+
errposition(pg_err_position())));
894+
warn_on_first_escape = false; /* warn only once per string */
895+
}
896+
else
897+
check_escape_warning();
898+
}
899+
878900
static void
879901
check_escape_warning(void)
880902
{

‎src/backend/utils/misc/guc.c

Lines changed: 3 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -10,7 +10,7 @@
1010
* Written by Peter Eisentraut <peter_e@gmx.net>.
1111
*
1212
* IDENTIFICATION
13-
* $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.312 2006/03/05 15:58:49 momjian Exp $
13+
* $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.313 2006/03/06 19:49:20 momjian Exp $
1414
*
1515
*--------------------------------------------------------------------
1616
*/
@@ -224,7 +224,6 @@ static int max_index_keys;
224224
static int max_identifier_length;
225225
static int block_size;
226226
static bool integer_datetimes;
227-
static bool standard_conforming_strings;
228227

229228
/* should be static, but commands/variable.c needs to get at these */
230229
char *role_string;
@@ -974,10 +973,10 @@ static struct config_bool ConfigureNamesBool[] =
974973
},
975974

976975
{
977-
{"standard_conforming_strings", PGC_INTERNAL, PRESET_OPTIONS,
976+
{"standard_conforming_strings", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
978977
gettext_noop("'...' strings treat backslashes literally."),
979978
NULL,
980-
GUC_REPORT | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
979+
GUC_REPORT
981980
},
982981
&standard_conforming_strings,
983982
false, NULL, NULL

‎src/backend/utils/misc/postgresql.conf.sample

Lines changed: 2 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -415,7 +415,8 @@
415415
#add_missing_from = off
416416
#array_nulls = on
417417
#default_with_oids = off
418-
#escape_string_warning = off
418+
#escape_string_warning = off # warn about backslashes in string literals
419+
#standard_conforming_strings = off # SQL standard string literal processing
419420
#regex_flavor = advanced # advanced, extended, or basic
420421
#sql_inheritance = on
421422

‎src/bin/psql/common.c

Lines changed: 24 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -3,7 +3,7 @@
33
*
44
* Copyright (c) 2000-2006, PostgreSQL Global Development Group
55
*
6-
* $PostgreSQL: pgsql/src/bin/psql/common.c,v 1.114 2006/03/05 15:58:51 momjian Exp $
6+
* $PostgreSQL: pgsql/src/bin/psql/common.c,v 1.115 2006/03/06 19:49:20 momjian Exp $
77
*/
88
#include "postgres_fe.h"
99
#include "common.h"
@@ -1328,6 +1328,29 @@ is_superuser(void)
13281328
}
13291329

13301330

1331+
/*
1332+
* Test if the current session uses standard string literals.
1333+
*
1334+
* Note: this will correctly detect the setting only with a protocol-3.0
1335+
* or newer backend; otherwise it will always say "false".
1336+
*/
1337+
bool
1338+
standard_strings(void)
1339+
{
1340+
const char *val;
1341+
1342+
if (!pset.db)
1343+
return false;
1344+
1345+
val = PQparameterStatus(pset.db, "standard_conforming_strings");
1346+
1347+
if (val && strcmp(val, "on") == 0)
1348+
return true;
1349+
1350+
return false;
1351+
}
1352+
1353+
13311354
/*
13321355
* Return the session user of the current connection.
13331356
*

‎src/bin/psql/common.h

Lines changed: 2 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -3,7 +3,7 @@
33
*
44
* Copyright (c) 2000-2006, PostgreSQL Global Development Group
55
*
6-
* $PostgreSQL: pgsql/src/bin/psql/common.h,v 1.46 2006/03/05 15:58:51 momjian Exp $
6+
* $PostgreSQL: pgsql/src/bin/psql/common.h,v 1.47 2006/03/06 19:49:20 momjian Exp $
77
*/
88
#ifndef COMMON_H
99
#define COMMON_H
@@ -57,6 +57,7 @@ extern PGresult *PSQLexec(const char *query, bool start_xact);
5757
extern bool SendQuery(const char *query);
5858

5959
extern bool is_superuser(void);
60+
extern bool standard_strings(void);
6061
extern const char *session_username(void);
6162

6263
extern char *expand_tilde(char **filename);

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