diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c index 3d6e6bdbfd2..27ba1920e68 100644 --- a/src/backend/utils/adt/ruleutils.c +++ b/src/backend/utils/adt/ruleutils.c @@ -3086,9 +3086,10 @@ pg_get_functiondef(PG_FUNCTION_ARGS) * rules used there aren't exactly like SQL's, we have to * break the list value apart and then quote the elements as * string literals. (The elements may be double-quoted as-is, - * but we can't just feed them to the SQL parser; it would do - * the wrong thing with elements that are zero-length or - * longer than NAMEDATALEN.) + * but we can't just feed them to the SQL parser that way; it + * would truncate elements that are longer than NAMEDATALEN, + * which would be wrong if they're paths.) Also, we need a + * special case for empty lists. * * Variables that are not so marked should just be emitted as * simple string literals. If the variable is not known to @@ -3106,6 +3107,9 @@ pg_get_functiondef(PG_FUNCTION_ARGS) /* this shouldn't fail really */ elog(ERROR, "invalid list syntax in proconfig item"); } + /* Special case: represent an empty list as '' */ + if (namelist == NIL) + appendStringInfoString(&buf, "''"); foreach(lc, namelist) { char *curname = (char *) lfirst(lc); diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c index 2c398cd9e5c..d5ef492ee41 100644 --- a/src/backend/utils/adt/varlena.c +++ b/src/backend/utils/adt/varlena.c @@ -2753,7 +2753,7 @@ SplitIdentifierString(char *rawstring, char separator, nextp++; /* skip leading whitespace */ if (*nextp == '\0') - return true; /* allow empty string */ + return true; /* empty string represents empty list */ /* At the top of the loop, we are at start of a new identifier. */ do @@ -2777,6 +2777,8 @@ SplitIdentifierString(char *rawstring, char separator, nextp = endp; } /* endp now points at the terminating quote */ + if (curname == endp) + return false; /* empty quoted name not allowed */ nextp = endp + 1; } else @@ -2880,7 +2882,7 @@ SplitDirectoriesString(char *rawstring, char separator, nextp++; /* skip leading whitespace */ if (*nextp == '\0') - return true; /* allow empty string */ + return true; /* empty string represents empty list */ /* At the top of the loop, we are at start of a new directory. */ do @@ -2904,6 +2906,8 @@ SplitDirectoriesString(char *rawstring, char separator, nextp = endp; } /* endp now points at the terminating quote */ + if (curname == endp) + return false; /* empty quoted name not allowed */ nextp = endp + 1; } else @@ -3001,7 +3005,7 @@ SplitGUCList(char *rawstring, char separator, nextp++; /* skip leading whitespace */ if (*nextp == '\0') - return true; /* allow empty string */ + return true; /* empty string represents empty list */ /* At the top of the loop, we are at start of a new identifier. */ do @@ -3025,6 +3029,8 @@ SplitGUCList(char *rawstring, char separator, nextp = endp; } /* endp now points at the terminating quote */ + if (curname == endp) + return false; /* empty quoted name not allowed */ nextp = endp + 1; } else diff --git a/src/backend/utils/misc/guc_funcs.c b/src/backend/utils/misc/guc_funcs.c index b9e26982abd..a0557d164d8 100644 --- a/src/backend/utils/misc/guc_funcs.c +++ b/src/backend/utils/misc/guc_funcs.c @@ -210,12 +210,30 @@ flatten_set_variable_args(const char *name, List *args) else flags = 0; - /* Complain if list input and non-list variable */ - if ((flags & GUC_LIST_INPUT) == 0 && - list_length(args) != 1) - ereport(ERROR, - (errcode(ERRCODE_INVALID_PARAMETER_VALUE), - errmsg("SET %s takes only one argument", name))); + /* + * Handle special cases for list input. + */ + if (flags & GUC_LIST_INPUT) + { + /* A single empty-string item is treated as an empty list. */ + if (list_length(args) == 1) + { + Node *arg = (Node *) linitial(args); + + if (IsA(arg, A_Const) && + nodeTag(&((A_Const *) arg)->val) == T_String && + *strVal(&((A_Const *) arg)->val) == '\0') + return pstrdup(""); + } + } + else + { + /* Complain if list input and non-list variable. */ + if (list_length(args) != 1) + ereport(ERROR, + (errcode(ERRCODE_INVALID_PARAMETER_VALUE), + errmsg("SET %s takes only one argument", name))); + } initStringInfo(&buf); @@ -269,6 +287,9 @@ flatten_set_variable_args(const char *name, List *args) Datum interval; char *intervalout; + /* gram.y ensures this is only reachable for TIME ZONE */ + Assert(!(flags & GUC_LIST_QUOTE)); + typenameTypeIdAndMod(NULL, typeName, &typoid, &typmod); Assert(typoid == INTERVALOID); @@ -286,9 +307,17 @@ flatten_set_variable_args(const char *name, List *args) else { /* - * Plain string literal or identifier. For quote mode, + * Plain string literal or identifier. In a list GUC, + * disallow empty-string elements (so that the preceding + * hack for empty lists is unambiguous). For quote mode, * quote it if it's not a vanilla identifier. */ + if ((flags & GUC_LIST_INPUT) && *val == '\0') + ereport(ERROR, + (errcode(ERRCODE_INVALID_PARAMETER_VALUE), + errmsg("SET %s does not accept empty-string elements", + name))); + if (flags & GUC_LIST_QUOTE) appendStringInfoString(&buf, quote_identifier(val)); else diff --git a/src/bin/pg_dump/dumputils.c b/src/bin/pg_dump/dumputils.c index 05b84c0d6e7..00a369c8861 100644 --- a/src/bin/pg_dump/dumputils.c +++ b/src/bin/pg_dump/dumputils.c @@ -781,7 +781,7 @@ SplitGUCList(char *rawstring, char separator, nextp++; /* skip leading whitespace */ if (*nextp == '\0') - return true; /* allow empty string */ + return true; /* empty string represents empty list */ /* At the top of the loop, we are at start of a new identifier. */ do @@ -805,6 +805,8 @@ SplitGUCList(char *rawstring, char separator, nextp = endp; } /* endp now points at the terminating quote */ + if (curname == endp) + return false; /* empty quoted name not allowed */ nextp = endp + 1; } else @@ -891,8 +893,9 @@ makeAlterConfigCommand(PGconn *conn, const char *configitem, * array. However, because the quoting rules used there aren't exactly * like SQL's, we have to break the list value apart and then quote the * elements as string literals. (The elements may be double-quoted as-is, - * but we can't just feed them to the SQL parser; it would do the wrong - * thing with elements that are zero-length or longer than NAMEDATALEN.) + * but we can't just feed them to the SQL parser that way; it would + * truncate elements that are longer than NAMEDATALEN, which would be + * wrong if they're paths.) Also, we need a special case for empty lists. * * Variables that are not so marked should just be emitted as simple * string literals. If the variable is not known to @@ -908,6 +911,9 @@ makeAlterConfigCommand(PGconn *conn, const char *configitem, /* this shouldn't fail really */ if (SplitGUCList(pos, ',', &namelist)) { + /* Special case: represent an empty list as '' */ + if (*namelist == NULL) + appendPQExpBufferStr(buf, "''"); for (nameptr = namelist; *nameptr; nameptr++) { if (nameptr != namelist) diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c index bea793456f9..9d36a6a5aaf 100644 --- a/src/bin/pg_dump/pg_dump.c +++ b/src/bin/pg_dump/pg_dump.c @@ -13699,8 +13699,9 @@ dumpFunc(Archive *fout, const FuncInfo *finfo) * aren't exactly like SQL's, we have to break the list value apart * and then quote the elements as string literals. (The elements may * be double-quoted as-is, but we can't just feed them to the SQL - * parser; it would do the wrong thing with elements that are - * zero-length or longer than NAMEDATALEN.) + * parser that way; it would truncate elements that are longer than + * NAMEDATALEN, which would be wrong if they're paths.) Also, we need + * a special case for empty lists. * * Variables that are not so marked should just be emitted as simple * string literals. If the variable is not known to @@ -13716,6 +13717,9 @@ dumpFunc(Archive *fout, const FuncInfo *finfo) /* this shouldn't fail really */ if (SplitGUCList(pos, ',', &namelist)) { + /* Special case: represent an empty list as '' */ + if (*namelist == NULL) + appendPQExpBufferStr(q, "''"); for (nameptr = namelist; *nameptr; nameptr++) { if (nameptr != namelist) diff --git a/src/test/regress/expected/guc.out b/src/test/regress/expected/guc.out index 7f9e29c765c..e49e609415b 100644 --- a/src/test/regress/expected/guc.out +++ b/src/test/regress/expected/guc.out @@ -31,6 +31,24 @@ SELECT '2006-08-13 12:34:56'::timestamptz; 2006-08-13 12:34:56-07 (1 row) +-- Check handling of list GUCs +SET search_path = 'pg_catalog', Foo, 'Bar'; +SHOW search_path; + search_path +------------------------ + pg_catalog, foo, "Bar" +(1 row) + +SET search_path = ''; -- means empty list +SHOW search_path; + search_path +------------- + +(1 row) + +SET search_path = '', 'foo'; -- error, empty list elements not OK +ERROR: SET search_path does not accept empty-string elements +RESET search_path; -- SET LOCAL has no effect outside of a transaction SET LOCAL vacuum_cost_delay TO 50; WARNING: SET LOCAL can only be used in transaction blocks diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out index 35e8aad7701..43d5cf10266 100644 --- a/src/test/regress/expected/rules.out +++ b/src/test/regress/expected/rules.out @@ -3549,21 +3549,23 @@ CREATE FUNCTION func_with_set_params() RETURNS integer SET extra_float_digits TO 2 SET work_mem TO '4MB' SET datestyle to iso, mdy - SET local_preload_libraries TO "Mixed/Case", 'c:/''a"/path', '', '0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789' + SET temp_tablespaces to '' + SET local_preload_libraries TO "Mixed/Case", 'c:/''a"/path', '0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789' IMMUTABLE STRICT; SELECT pg_get_functiondef('func_with_set_params()'::regprocedure); - pg_get_functiondef --------------------------------------------------------------------------------------------------------------------------------------------------------------------------- - CREATE OR REPLACE FUNCTION public.func_with_set_params() + - RETURNS integer + - LANGUAGE sql + - IMMUTABLE STRICT + - SET search_path TO 'pg_catalog' + - SET extra_float_digits TO '2' + - SET work_mem TO '4MB' + - SET "DateStyle" TO 'iso, mdy' + - SET local_preload_libraries TO 'Mixed/Case', 'c:/''a"/path', '', '0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789'+ - AS $function$select 1;$function$ + + pg_get_functiondef +---------------------------------------------------------------------------------------------------------------------------------------------------------------------- + CREATE OR REPLACE FUNCTION public.func_with_set_params() + + RETURNS integer + + LANGUAGE sql + + IMMUTABLE STRICT + + SET search_path TO 'pg_catalog' + + SET extra_float_digits TO '2' + + SET work_mem TO '4MB' + + SET "DateStyle" TO 'iso, mdy' + + SET temp_tablespaces TO '' + + SET local_preload_libraries TO 'Mixed/Case', 'c:/''a"/path', '0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789'+ + AS $function$select 1;$function$ + (1 row) diff --git a/src/test/regress/sql/guc.sql b/src/test/regress/sql/guc.sql index f65f84a2632..65630135f18 100644 --- a/src/test/regress/sql/guc.sql +++ b/src/test/regress/sql/guc.sql @@ -12,6 +12,14 @@ SHOW vacuum_cost_delay; SHOW datestyle; SELECT '2006-08-13 12:34:56'::timestamptz; +-- Check handling of list GUCs +SET search_path = 'pg_catalog', Foo, 'Bar'; +SHOW search_path; +SET search_path = ''; -- means empty list +SHOW search_path; +SET search_path = '', 'foo'; -- error, empty list elements not OK +RESET search_path; + -- SET LOCAL has no effect outside of a transaction SET LOCAL vacuum_cost_delay TO 50; SHOW vacuum_cost_delay; diff --git a/src/test/regress/sql/rules.sql b/src/test/regress/sql/rules.sql index fdd3ff1d161..5c5ff5e9cca 100644 --- a/src/test/regress/sql/rules.sql +++ b/src/test/regress/sql/rules.sql @@ -1217,7 +1217,8 @@ CREATE FUNCTION func_with_set_params() RETURNS integer SET extra_float_digits TO 2 SET work_mem TO '4MB' SET datestyle to iso, mdy - SET local_preload_libraries TO "Mixed/Case", 'c:/''a"/path', '', '0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789' + SET temp_tablespaces to '' + SET local_preload_libraries TO "Mixed/Case", 'c:/''a"/path', '0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789' IMMUTABLE STRICT; SELECT pg_get_functiondef('func_with_set_params()'::regprocedure);