database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-25 01:02:05 +03:00
Code Activity

Avoid premature de-doubling of quote marks in ECPG strings.

Browse Source 
If you write the literal 'abc''def' in an EXEC SQL command, that will
come out the other end as 'abc'def', triggering a syntax error in the
backend.  Likewise, "abc""def" is reduced to "abc"def" which is wrong
syntax for a quoted identifier.

The cause is that the lexer thinks it should emit just one quote
mark, whereas what it really should do is keep the string as-is.

Add some docs and test cases, too.

Although this seems clearly a bug, I fear users wouldn't appreciate
changing it in minor releases.  Some may well be working around it
by applying an extra doubling of affected quotes, as for example
sql/dyntest.pgc has been doing.

Per investigation of a report from 1250kv, although this isn't
exactly what he/she was on about.

Discussion: https://postgr.es/m/673825.1603223178@sss.pgh.pa.us
This commit is contained in:
Tom Lane
2020-10-22 17:34:32 -04:00
parent 8bb0c9770e
commit 3dfb1942d9
7 changed files with 28 additions and 20 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
src/interfaces/ecpg/preproc/pgc.l
View File

@ -623,11 +623,8 @@ cppline {space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
}
}
<xq,xe,xn,xus>{xqdouble} { addlitchar('\''); }
<xqc>{xqcquote} {
addlitchar('\\');
addlitchar('\'');
}
<xq,xe,xn,xus>{xqdouble} { addlit(yytext, yyleng); }
<xqc>{xqcquote} { addlit(yytext, yyleng); }
<xq,xqc,xn,xus>{xqinside} { addlit(yytext, yyleng); }
<xe>{xeinside} {
addlit(yytext, yyleng);
@ -736,7 +733,7 @@ cppline {space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
return UIDENT;
}
<xd,xui>{xddouble} {
addlitchar('"');
addlit(yytext, yyleng);
}
<xd,xui>{xdinside} {
addlit(yytext, yyleng);

2
src/interfaces/ecpg/test/expected/preproc-strings.c
View File

@ -45,7 +45,7 @@ int main(void)
#line 13 "strings.pgc"
{ ECPGdo(__LINE__, 0, 1, NULL, 0, ECPGst_normal, "select 'abcdef' , N'abcdef' as foo , E'abc\\bdef' as \"foo\" , U&'d\\0061t\\0061' as U&\"foo\" , U&'d!+000061t!+000061' UESCAPE '!' , $foo$abc$def$foo$", ECPGt_EOIT,
{ ECPGdo(__LINE__, 0, 1, NULL, 0, ECPGst_normal, "select 'abc''d\\ef' , N'abc''d\\ef' as foo , E'abc''d\\\\ef' as \"foo\"\"bar\" , U&'d\\0061t\\0061' as U&\"foo\"\"bar\" , U&'d!+000061t!+000061' UESCAPE '!' , $foo$abc$def$foo$", ECPGt_EOIT,
ECPGt_char,&(s1),(long)0,(long)1,(1)*sizeof(char),
ECPGt_NO_INDICATOR, NULL , 0L, 0L, 0L,
ECPGt_char,&(s2),(long)0,(long)1,(1)*sizeof(char),

8
src/interfaces/ecpg/test/expected/preproc-strings.stderr
View File

@ -8,7 +8,7 @@
[NO_PID]: sqlca: code: 0, state: 00000
[NO_PID]: ecpg_process_output on line 13: OK: SET
[NO_PID]: sqlca: code: 0, state: 00000
[NO_PID]: ecpg_execute on line 15: query: select 'abcdef' , N'abcdef' as foo , E'abc\bdef' as "foo" , U&'d\0061t\0061' as U&"foo" , U&'d!+000061t!+000061' UESCAPE '!' , $foo$abc$def$foo$; with 0 parameter(s) on connection ecpg1_regression
[NO_PID]: ecpg_execute on line 15: query: select 'abc''d\ef' , N'abc''d\ef' as foo , E'abc''d\\ef' as "foo""bar" , U&'d\0061t\0061' as U&"foo""bar" , U&'d!+000061t!+000061' UESCAPE '!' , $foo$abc$def$foo$; with 0 parameter(s) on connection ecpg1_regression
[NO_PID]: sqlca: code: 0, state: 00000
[NO_PID]: ecpg_execute on line 15: using PQexec
[NO_PID]: sqlca: code: 0, state: 00000
@ -16,15 +16,15 @@
[NO_PID]: sqlca: code: 0, state: 00000
[NO_PID]: ecpg_store_result on line 15: allocating memory for 1 tuples
[NO_PID]: sqlca: code: 0, state: 00000
[NO_PID]: ecpg_get_data on line 15: RESULT: abcdef offset: -1; array: no
[NO_PID]: ecpg_get_data on line 15: RESULT: abc'd\ef offset: -1; array: no
[NO_PID]: sqlca: code: 0, state: 00000
[NO_PID]: ecpg_store_result on line 15: allocating memory for 1 tuples
[NO_PID]: sqlca: code: 0, state: 00000
[NO_PID]: ecpg_get_data on line 15: RESULT: abcdef offset: -1; array: no
[NO_PID]: ecpg_get_data on line 15: RESULT: abc'd\ef offset: -1; array: no
[NO_PID]: sqlca: code: 0, state: 00000
[NO_PID]: ecpg_store_result on line 15: allocating memory for 1 tuples
[NO_PID]: sqlca: code: 0, state: 00000
[NO_PID]: ecpg_get_data on line 15: RESULT: abcdef offset: -1; array: no
[NO_PID]: ecpg_get_data on line 15: RESULT: abc'd\ef offset: -1; array: no
[NO_PID]: sqlca: code: 0, state: 00000
[NO_PID]: ecpg_store_result on line 15: allocating memory for 1 tuples
[NO_PID]: sqlca: code: 0, state: 00000

2
src/interfaces/ecpg/test/expected/preproc-strings.stdout
View File

@ -1 +1 @@
abcdef abcdef abcdef data data abc$def
abc'd\ef abc'd\ef abc'd\ef data data abc$def

8
src/interfaces/ecpg/test/preproc/strings.pgc
View File

@ -12,10 +12,10 @@ int main(void)
exec sql set standard_conforming_strings to on;
exec sql select 'abcdef',
N'abcdef' AS foo,
E'abc\bdef' AS "foo",
U&'d\0061t\0061' AS U&"foo",
exec sql select 'abc''d\ef',
N'abc''d\ef' AS foo,
E'abc''d\\ef' AS "foo""bar",
U&'d\0061t\0061' AS U&"foo""bar",
U&'d!+000061t!+000061' uescape '!',
$foo$abc$def$foo$
into :s1, :s2, :s3, :s4, :s5, :s6;

2
src/interfaces/ecpg/test/sql/dyntest.pgc
View File

@ -51,7 +51,7 @@ main ()
exec sql create table dyntest (name char (14), d float8, i int,
bignumber int8, b boolean, comment text,
day date);
exec sql insert into dyntest values ('first entry', 14.7, 14, 123045607890, true, 'The world''''s most advanced open source database.', '1987-07-14');
exec sql insert into dyntest values ('first entry', 14.7, 14, 123045607890, true, 'The world''s most advanced open source database.', '1987-07-14');
exec sql insert into dyntest values ('second entry', 1407.87, 1407, 987065403210, false, 'The elephant never forgets.', '1999-11-5');
exec sql prepare MYQUERY from :QUERY;