Hello
2010/9/29 Itagaki Takahiro <[email protected]>:
> On Thu, Sep 9, 2010 at 8:57 PM, Pavel Stehule <[email protected]> wrote:
>> I am sending a updated version.
>>
>> changes:
>> * tag %v removed from format function,
>> * proprietary tags %lq a iq removed from sprintf
>> * code cleaned
>>
>> patch divided to two parts - format function and stringfunc (contains
>> sprintf function and substitute function)
>
> === Discussions about the spec ===
> Two patches add format() into the core, and substitute() and sprintf() into
> stringfunc contrib module. But will we have 3 versions of string formatters?
>
> IMHO, substitute() is the best choice that we will have in the core because
> functionalities in format() and sprintf() can be achieved by combination of
> substitute() and quote_nullable(), quote_ident(), or to_char(). I think the
> core will provide only simple and non-overlapped features. Users can write
> wrapper functions by themselves if they think the description is redundant.
I think we need a three variants of formating functions - "format" in
core, fo simply creating and building a messages, a SQL strings,
"sprintf" for traditionalist in contrib - this functions isn't well
joined to SQL environment and it's too heavy - more it overwrite a
some functionality of "to_char" function. "substitute" function
provide just positional unformatted parameters - that isn't typical
ucase - so must not be in core too.
>
> === format.diff ===
> * It has a reject in doc, but the hunk can be fixed easily.
> 1 out of 2 hunks FAILED -- saving rejects to file
> doc/src/sgml/func.sgml.rej
> COMMENT: We have the function list in alphabetical order,
fixed
> so format() should be inserted after encode().
> * It can be built without compile warnings.
> * Enough documentation and regression tests are included.
>
> === stringfunc.diff ===
> * It can be applied cleanly and built without compile warnings.
> * Documentation is included, but not enough.
> COMMENT: According to existing docs, function list are described with
> <variablelist> or <table>.
fixed
> * Enough regression tests are included.
> * COMMENT: stringfunc directory should be added to contrib/Makefile.
>
> * BUG: stringfunc_substitute_nv() calls text_format().
> I think we don't need stringfunc_substitute_nv at all.
> It can be replaced by stringfunc_substitute(). _nv version is only
> required if it is in the core because of sanity regression test.
you have a true - but I am not sure about coding patters for contribs,
so I designed it with respect to core sanity check.
>
> * BUG?: The doc says sprintf() doesn't support length modifiers,
> but it is actually supported in broken state:
I was wrong in documentation - length modifiers are supported -
positional modifiers are not supported. fixed.
> postgres=# SELECT sprintf('%*s', 2, 'ABC');
> sprintf
> ---------
> ABC <= should be ERROR if unsupported, or AB if supported.
> (1 row)
it works well - "with" modifier doesn't reduce string. String is
stripped by "precision" modifiers.
SELECT sprintf('%*.s', 2, ABC) --> AB
checked via gcc
please, try
printf(">>%s<<\n", "12345678");
printf(">>%3s<<\n", "12345678");
printf(">>%.3s<<\n", "12345678");
printf(">>%10.3s<<\n", "12345678");
do you understand me, why I "dislike" "printf"? How much people knows
well these formatting rules?
>
> * BUG?: ereport(ERROR,
> (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
> errmsg("unsupported tag \"%%%c\"", tag)));
> Is the code ok if the tag (a char) is a partial byte of multi-byte character?
it's bug - the supported tags are only single byte, but unsupported
tag can be multibyte character and must by showed correctly - fixed.
> My machine prints ? in the case, but it might be platform-dependent.
>
> === Both patches ===
> * Performance: I don't think those functions are not performance-critical,
> but we could cache typoutput functions in fn_extra if needed.
> record_out would be a reference.
I though about it too and I checked it now - there is 0.4% performance
on 10000000 rows on my PC (format function) - so I don't do any
changes - caching of oids means a few lines more - but here isn't
expected effect.
>
> * Coding: Whitespace and tabs are mixed in some places. They are not so
> important because we will run pgindent, but careful choice will be
> preferred even of a patch.
>
checked, fixed
Thank you very much for review
regards
Pavel Stehule
> --
> Itagaki Takahiro
>
*** ./doc/src/sgml/func.sgml.orig 2010-09-09 02:48:22.000000000 +0200
--- ./doc/src/sgml/func.sgml 2010-09-29 07:18:59.845395002 +0200
***************
*** 1272,1277 ****
--- 1272,1280 ----
<primary>encode</primary>
</indexterm>
<indexterm>
+ <primary>format</primary>
+ </indexterm>
+ <indexterm>
<primary>initcap</primary>
</indexterm>
<indexterm>
***************
*** 1495,1500 ****
--- 1498,1520 ----
<entry><literal>encode(E'123\\000\\001', 'base64')</literal></entry>
<entry><literal>MTIzAAE=</literal></entry>
</row>
+
+ </row>
+ <entry>
+ <literal><function>format</function>(<parameter>formatstr</parameter> <type>text</type>
+ [, <parameter>str</parameter> <type>"any"</type> [, ...] ])</literal>
+ </entry>
+ <entry><type>text</type></entry>
+ <entry>
+ This functions can be used to create a formated string or message. There are allowed
+ three types of tags: %s as string, %i as SQL identifiers and %l as SQL literals. Attention:
+ result for %i and %l must not be same as result of <function>quote_ident</function> and
+ <function>quote_literal</function> functions, because this function doesn't try to coerce
+ parameters to <type>text</type> type and directly use a type's output functions.
+ </entry>
+ <entry><literal>format('Hello %s', 'World')</literal></entry>
+ <entry><literal>Hello World</literal></entry>
+ </row>
<row>
<entry><literal><function>initcap(<parameter>string</parameter>)</function></literal></entry>
*** ./src/backend/utils/adt/varlena.c.orig 2010-09-29 07:16:25.744395786 +0200
--- ./src/backend/utils/adt/varlena.c 2010-09-29 09:51:39.340270718 +0200
***************
*** 21,28 ****
--- 21,30 ----
#include "libpq/md5.h"
#include "libpq/pqformat.h"
#include "miscadmin.h"
+ #include "parser/parse_coerce.h"
#include "parser/scansup.h"
#include "regex/regex.h"
+ #include "utils/array.h"
#include "utils/builtins.h"
#include "utils/bytea.h"
#include "utils/lsyscache.h"
***************
*** 48,53 ****
--- 50,61 ----
int skiptable[256]; /* skip distance for given mismatched char */
} TextPositionState;
+ typedef struct
+ {
+ int n_valid_oids;
+ Oid typoutput[FUNC_MAX_ARGS];
+ } format_fn_extra_cache;
+
#define DatumGetUnknownP(X) ((unknown *) PG_DETOAST_DATUM(X))
#define DatumGetUnknownPCopy(X) ((unknown *) PG_DETOAST_DATUM_COPY(X))
#define PG_GETARG_UNKNOWN_P(n) DatumGetUnknownP(PG_GETARG_DATUM(n))
***************
*** 3702,3704 ****
--- 3710,3866 ----
PG_RETURN_TEXT_P(result);
}
+
+ /*
+ * Text format - a variadic function replaces %c symbols with entered text.
+ */
+ Datum
+ text_format(PG_FUNCTION_ARGS)
+ {
+ text *fmt;
+ StringInfoData str;
+ char *cp;
+ int i = 1;
+ size_t len;
+ char *start_ptr;
+ char *end_ptr;
+ text *result;
+
+ /* When format string is null, returns null */
+ if (PG_ARGISNULL(0))
+ PG_RETURN_NULL();
+
+ fmt = PG_GETARG_TEXT_PP(0);
+ len = VARSIZE_ANY_EXHDR(fmt);
+ start_ptr = VARDATA_ANY(fmt);
+ end_ptr = start_ptr + len - 1;
+
+ initStringInfo(&str);
+ for (cp = start_ptr; cp <= end_ptr; cp++)
+ {
+ /*
+ * there are allowed escape char - '\'
+ */
+ if (cp[0] == '\\')
+ {
+ /* check next char */
+ if (cp < end_ptr)
+ {
+ switch (cp[1])
+ {
+ case '\\':
+ case '%':
+ appendStringInfoChar(&str, cp[1]);
+ break;
+
+ default:
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("unsupported escape sequence \\%.*s", pg_mblen(&cp[1]), &cp[1])));
+ }
+ cp++;
+ }
+ else
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("broken escape sequence")));
+ }
+ else if (cp[0] == '%')
+ {
+ char tag;
+
+ /* initial check */
+ if (cp == end_ptr)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("missing formating tag")));
+
+ if (i >= PG_NARGS())
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("too few parameters for format function")));
+
+ tag = cp[1];
+ cp++;
+
+ if (!PG_ARGISNULL(i))
+ {
+ Oid valtype;
+ Datum value;
+ Oid typoutput;
+ bool typIsVarlena;
+
+ /* append n-th value */
+ value = PG_GETARG_DATUM(i);
+ valtype = get_fn_expr_argtype(fcinfo->flinfo, i);
+ getTypeOutputInfo(valtype, &typoutput, &typIsVarlena);
+
+ if (tag == 's')
+ {
+ /* show it as unspecified string */
+ appendStringInfoString(&str, OidOutputFunctionCall(typoutput, value));
+ }
+ else if (tag == 'i')
+ {
+ char *target_value;
+
+ /* show it as sql identifier */
+ target_value = OidOutputFunctionCall(typoutput, value);
+ appendStringInfoString(&str, quote_identifier(target_value));
+ }
+ else if (tag == 'l')
+ {
+ text *txt;
+ text *quoted_txt;
+
+ /* get text value and quotize */
+ txt = cstring_to_text(OidOutputFunctionCall(typoutput, value));
+ quoted_txt = DatumGetTextP(DirectFunctionCall1(quote_literal,
+ PointerGetDatum(txt)));
+ appendStringInfoString(&str, text_to_cstring(quoted_txt));
+ }
+ else
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("unsupported tag \"%%%.*s\"", pg_mblen(cp), cp)));
+ }
+ else
+ {
+ if (tag == 'i')
+ ereport(ERROR,
+ (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
+ errmsg("NULL is used as SQL identifier")));
+ else if (tag == 'l')
+ appendStringInfoString(&str, "NULL");
+ else if (tag != 's')
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("unsupported tag \"%%%.*s\"", pg_mblen(cp), cp)));
+ }
+ i++;
+ }
+ else
+ appendStringInfoChar(&str, cp[0]);
+ }
+
+ /* check if all arguments are used */
+ if (i != PG_NARGS())
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("too many parameters for format function")));
+
+ result = cstring_to_text_with_len(str.data, str.len);
+ pfree(str.data);
+
+ PG_RETURN_TEXT_P(result);
+ }
+
+ /*
+ * Non variadic text_format function - only wrapper
+ * Print and check format string
+ */
+ Datum
+ text_format_nv(PG_FUNCTION_ARGS)
+ {
+ return text_format(fcinfo);
+ }
*** ./src/include/catalog/pg_proc.h.orig 2010-09-03 03:34:55.000000000 +0200
--- ./src/include/catalog/pg_proc.h 2010-09-29 07:16:42.658395449 +0200
***************
*** 2741,2746 ****
--- 2741,2750 ----
DESCR("return the last n characters");
DATA(insert OID = 3062 ( reverse PGNSP PGUID 12 1 0 0 f f f t f i 1 0 25 "25" _null_ _null_ _null_ _null_ text_reverse _null_ _null_ _null_ ));
DESCR("reverse text");
+ DATA(insert OID = 3063 ( format PGNSP PGUID 12 1 0 2276 f f f f f s 2 0 25 "25 2276" "{25,2276}" "{i,v}" _null_ _null_ text_format _null_ _null_ _null_ ));
+ DESCR("format text message");
+ DATA(insert OID = 3064 ( format PGNSP PGUID 12 1 0 0 f f f f f s 1 0 25 "25" _null_ _null_ _null_ _null_ text_format_nv _null_ _null_ _null_ ));
+ DESCR("format text message");
DATA(insert OID = 1810 ( bit_length PGNSP PGUID 14 1 0 0 f f f t f i 1 0 23 "17" _null_ _null_ _null_ _null_ "select pg_catalog.octet_length($1) * 8" _null_ _null_ _null_ ));
DESCR("length in bits");
*** ./src/include/utils/builtins.h.orig 2010-09-03 03:34:55.000000000 +0200
--- ./src/include/utils/builtins.h 2010-09-29 07:16:42.661395833 +0200
***************
*** 742,747 ****
--- 742,749 ----
extern Datum text_left(PG_FUNCTION_ARGS);
extern Datum text_right(PG_FUNCTION_ARGS);
extern Datum text_reverse(PG_FUNCTION_ARGS);
+ extern Datum text_format(PG_FUNCTION_ARGS);
+ extern Datum text_format_nv(PG_FUNCTION_ARGS);
/* version.c */
extern Datum pgsql_version(PG_FUNCTION_ARGS);
*** ./src/test/regress/expected/text.out.orig 2010-09-29 07:16:25.749395800 +0200
--- ./src/test/regress/expected/text.out 2010-09-29 07:16:42.662395333 +0200
***************
*** 118,120 ****
--- 118,139 ----
5 | ahoj | ahoj
(11 rows)
+ select format('some text');
+ format
+ -----------
+ some text
+ (1 row)
+
+ select format('-- insert into %i (a,b,c) values(%l,%l,%l)', 'My tab', 'Hello', NULL, 10);
+ format
+ -----------------------------------------------------------
+ -- insert into "My tab" (a,b,c) values('Hello',NULL,'10')
+ (1 row)
+
+ -- should fail
+ select format('-- insert into %i (a,b,c) values(%l,%l,%l)', NULL, 'Hello', NULL, 10);
+ ERROR: NULL is used as SQL identifier
+ select format('-- insert into %i (a,b,c) values(%l,%l,%l)', 'My tab', NULL, 'Hello');
+ ERROR: too few parameters for format function
+ select format('-- insert into %i (a,b,c) values(%l,%l,%l)', 'My tab', 'Hello', NULL, 10, 10);
+ ERROR: too many parameters for format function
*** ./src/test/regress/sql/text.sql.orig 2010-09-29 07:16:25.751395218 +0200
--- ./src/test/regress/sql/text.sql 2010-09-29 07:16:42.662395333 +0200
***************
*** 41,43 ****
--- 41,49 ----
select concat_ws(NULL,10,20,null,30) is null;
select reverse('abcde');
select i, left('ahoj', i), right('ahoj', i) from generate_series(-5, 5) t(i) order by i;
+ select format('some text');
+ select format('-- insert into %i (a,b,c) values(%l,%l,%l)', 'My tab', 'Hello', NULL, 10);
+ -- should fail
+ select format('-- insert into %i (a,b,c) values(%l,%l,%l)', NULL, 'Hello', NULL, 10);
+ select format('-- insert into %i (a,b,c) values(%l,%l,%l)', 'My tab', NULL, 'Hello');
+ select format('-- insert into %i (a,b,c) values(%l,%l,%l)', 'My tab', 'Hello', NULL, 10, 10);
*** ./contrib/Makefile.orig 2010-06-14 18:17:56.000000000 +0200
--- ./contrib/Makefile 2010-09-29 08:14:37.569273826 +0200
***************
*** 40,45 ****
--- 40,46 ----
pgstattuple \
seg \
spi \
+ stringfunc \
tablefunc \
test_parser \
tsearch2 \
*** ./contrib/stringfunc/expected/stringfunc.out.orig 2010-09-29 08:11:40.945271948 +0200
--- ./contrib/stringfunc/expected/stringfunc.out 2010-09-29 08:10:48.363270909 +0200
***************
*** 0 ****
--- 1,101 ----
+ SET client_min_messages = warning;
+ \set ECHO none
+ RESET client_min_messages;
+ -- sprintf test
+ select sprintf('>>>%10s %10d<<<', 'hello', 10);
+ sprintf
+ -----------------------------
+ >>> hello 10<<<
+ (1 row)
+
+ select sprintf('>>>%-10s<<<', 'hello');
+ sprintf
+ ------------------
+ >>>hello <<<
+ (1 row)
+
+ select sprintf('>>>%5.2<<<', 'abcde');
+ ERROR: unsupported sprintf format tag '<'
+ select sprintf('>>>%*s<<<', 10, 'abcdef');
+ sprintf
+ ------------------
+ >>> abcdef<<<
+ (1 row)
+
+ select sprintf('>>>%*s<<<', 10); -- error
+ ERROR: too few parameters specified for printf function
+ select sprintf('%010d', 10);
+ sprintf
+ ------------
+ 0000000010
+ (1 row)
+
+ select sprintf('%.6d', 10);
+ sprintf
+ ---------
+ 000010
+ (1 row)
+
+ select sprintf('%d', 100.0/3.0);
+ sprintf
+ ---------
+ 33
+ (1 row)
+
+ select sprintf('%e', 100.0/3.0);
+ sprintf
+ --------------
+ 3.333333e+01
+ (1 row)
+
+ select sprintf('%f', 100.0/3.0);
+ sprintf
+ -----------
+ 33.333333
+ (1 row)
+
+ select sprintf('%g', 100.0/3.0);
+ sprintf
+ ---------
+ 33.3333
+ (1 row)
+
+ select sprintf('%7.4e', 100.0/3.0);
+ sprintf
+ ------------
+ 3.3333e+01
+ (1 row)
+
+ select sprintf('%7.4f', 100.0/3.0);
+ sprintf
+ ---------
+ 33.3333
+ (1 row)
+
+ select sprintf('%7.4g', 100.0/3.0);
+ sprintf
+ ---------
+ 33.33
+ (1 row)
+
+ select sprintf('%d', NULL);
+ sprintf
+ ---------
+ <NULL>
+ (1 row)
+
+ select substitute('second parameter is $2 and first parameter is $1', 'FIRST', 'SECOND');
+ substitute
+ ---------------------------------------------------------
+ second parameter is SECOND and first parameter is FIRST
+ (1 row)
+
+ -- should fail
+ select substitute('third parameter is $3 and first parameter is $1', 'FIRST', 'SECOND');
+ ERROR: positional placeholder "$3" is not valid
+ select substitute(' NULL parameter is $1', NULL);
+ substitute
+ ---------------------------
+ NULL parameter is <NULL>
+ (1 row)
+
*** ./contrib/stringfunc/Makefile.orig 2010-09-29 08:11:59.217397393 +0200
--- ./contrib/stringfunc/Makefile 2010-09-29 08:10:48.364270479 +0200
***************
*** 0 ****
--- 1,20 ----
+ # $PostgreSQL: pgsql/contrib/stringfunc/Makefile,v 1.23 2009/08/28 20:26:18 petere Exp $
+
+ MODULE_big = stringfunc
+ OBJS= stringfunc.o
+
+ DATA_built = stringfunc.sql
+ DATA = uninstall_stringfunc.sql
+ REGRESS = stringfunc
+
+ ifdef USE_PGXS
+ PG_CONFIG = pg_config
+ PGXS := $(shell $(PG_CONFIG) --pgxs)
+ include $(PGXS)
+ else
+ subdir = contrib/stringfunc
+ top_builddir = ../..
+ include $(top_builddir)/src/Makefile.global
+ include $(top_srcdir)/contrib/contrib-global.mk
+ endif
+
*** ./contrib/stringfunc/sql/stringfunc.sql.orig 2010-09-29 08:11:52.441397426 +0200
--- ./contrib/stringfunc/sql/stringfunc.sql 2010-09-29 08:10:48.364270479 +0200
***************
*** 0 ****
--- 1,28 ----
+ SET client_min_messages = warning;
+ \set ECHO none
+ \i stringfunc.sql
+ \set ECHO all
+ RESET client_min_messages;
+
+ -- sprintf test
+ select sprintf('>>>%10s %10d<<<', 'hello', 10);
+ select sprintf('>>>%-10s<<<', 'hello');
+ select sprintf('>>>%5.2<<<', 'abcde');
+ select sprintf('>>>%*s<<<', 10, 'abcdef');
+ select sprintf('>>>%*s<<<', 10); -- error
+ select sprintf('%010d', 10);
+ select sprintf('%.6d', 10);
+
+ select sprintf('%d', 100.0/3.0);
+ select sprintf('%e', 100.0/3.0);
+ select sprintf('%f', 100.0/3.0);
+ select sprintf('%g', 100.0/3.0);
+ select sprintf('%7.4e', 100.0/3.0);
+ select sprintf('%7.4f', 100.0/3.0);
+ select sprintf('%7.4g', 100.0/3.0);
+ select sprintf('%d', NULL);
+
+ select substitute('second parameter is $2 and first parameter is $1', 'FIRST', 'SECOND');
+ -- should fail
+ select substitute('third parameter is $3 and first parameter is $1', 'FIRST', 'SECOND');
+ select substitute(' NULL parameter is $1', NULL);
\ No newline at end of file
*** ./contrib/stringfunc/stringfunc.c.orig 2010-09-29 08:12:07.209397369 +0200
--- ./contrib/stringfunc/stringfunc.c 2010-09-29 09:42:33.306272084 +0200
***************
*** 0 ****
--- 1,666 ----
+ #include "postgres.h"
+ #include "string.h"
+
+ #include "catalog/pg_type.h"
+ #include "lib/stringinfo.h"
+ #include "mb/pg_wchar.h"
+ #include "parser/parse_coerce.h"
+ #include "utils/array.h"
+ #include "utils/builtins.h"
+ #include "utils/lsyscache.h"
+
+ PG_MODULE_MAGIC;
+
+ #define CHECK_PAD(symbol, pad_value) \
+ do { \
+ if (pdesc->flags & pad_value) \
+ ereport(ERROR, \
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE), \
+ errmsg("broken sprintf format"), \
+ errdetail("Format string is '%s'.", TextDatumGetCString(fmt)), \
+ errhint("Symbol '%c' can be used only one time.", symbol))); \
+ pdesc->flags |= pad_value; \
+ } while(0);
+
+ /*
+ * string functions
+ */
+ Datum stringfunc_sprintf(PG_FUNCTION_ARGS);
+ Datum stringfunc_sprintf_nv(PG_FUNCTION_ARGS);
+ Datum stringfunc_substitute(PG_FUNCTION_ARGS);
+ Datum stringfunc_substitute_nv(PG_FUNCTION_ARGS);
+
+ /*
+ * V1 registrations
+ */
+ PG_FUNCTION_INFO_V1(stringfunc_sprintf);
+ PG_FUNCTION_INFO_V1(stringfunc_sprintf_nv);
+ PG_FUNCTION_INFO_V1(stringfunc_substitute);
+ PG_FUNCTION_INFO_V1(stringfunc_substitute_nv);
+
+ typedef enum {
+ stringfunc_ZERO = 1,
+ stringfunc_SPACE = 2,
+ stringfunc_PLUS = 4,
+ stringfunc_MINUS = 8,
+ stringfunc_STAR_WIDTH = 16,
+ stringfunc_SHARP = 32,
+ stringfunc_WIDTH = 64,
+ stringfunc_PRECISION = 128,
+ stringfunc_STAR_PRECISION = 256
+ } PlaceholderTags;
+
+ typedef struct {
+ int flags;
+ char field_type;
+ char lenmod;
+ int32 width;
+ int32 precision;
+ } FormatPlaceholderData;
+
+ typedef FormatPlaceholderData *PlaceholderDesc;
+
+ static Datum
+ castValueTo(Datum value, Oid targetTypeId, Oid inputTypeId)
+ {
+ Oid funcId;
+ CoercionPathType pathtype;
+ FmgrInfo finfo;
+ Datum result;
+
+ if (inputTypeId != UNKNOWNOID)
+ pathtype = find_coercion_pathway(targetTypeId, inputTypeId,
+ COERCION_EXPLICIT,
+ &funcId);
+ else
+ pathtype = COERCION_PATH_COERCEVIAIO;
+
+ switch (pathtype)
+ {
+ case COERCION_PATH_RELABELTYPE:
+ result = value;
+ break;
+ case COERCION_PATH_FUNC:
+ {
+ Assert(OidIsValid(funcId));
+
+ fmgr_info(funcId, &finfo);
+ result = FunctionCall1(&finfo, value);
+ }
+ break;
+
+ case COERCION_PATH_COERCEVIAIO:
+ {
+ Oid typoutput;
+ Oid typinput;
+ bool typIsVarlena;
+ Oid typIOParam;
+ char *extval;
+
+ getTypeOutputInfo(inputTypeId, &typoutput, &typIsVarlena);
+ extval = OidOutputFunctionCall(typoutput, value);
+
+ getTypeInputInfo(targetTypeId, &typinput, &typIOParam);
+ result = OidInputFunctionCall(typinput, extval, typIOParam, -1);
+ }
+ break;
+
+ default:
+ elog(ERROR, "failed to find conversion function from %s to %s",
+ format_type_be(inputTypeId), format_type_be(targetTypeId));
+ /* be compiler quiet */
+ result = (Datum) 0;
+ }
+
+ return result;
+ }
+
+ /*
+ * parse and verify sprintf parameter
+ *
+ * %[flags][width][.precision]specifier
+ *
+ */
+ static char *
+ parsePlaceholder(char *src, char *end_ptr, PlaceholderDesc pdesc, text *fmt)
+ {
+ char c;
+
+ pdesc->field_type = '\0';
+ pdesc->lenmod = '\0';
+ pdesc->flags = 0;
+ pdesc->width = 0;
+ pdesc->precision = 0;
+
+ while (src < end_ptr && pdesc->field_type == '\0')
+ {
+ c = *++src;
+
+ switch (c)
+ {
+ case '0':
+ CHECK_PAD('0', stringfunc_ZERO);
+ break;
+ case ' ':
+ CHECK_PAD(' ', stringfunc_SPACE);
+ break;
+ case '+':
+ CHECK_PAD('+', stringfunc_PLUS);
+ break;
+ case '-':
+ CHECK_PAD('-', stringfunc_MINUS);
+ break;
+ case '*':
+ CHECK_PAD('*', stringfunc_STAR_WIDTH);
+ break;
+ case '#':
+ CHECK_PAD('#', stringfunc_SHARP);
+ break;
+ case 'o': case 'i': case 'e': case 'E': case 'f':
+ case 'g': case 'd': case 's': case 'x': case 'X':
+ pdesc->field_type = *src;
+ break;
+ case '1': case '2': case '3': case '4':
+ case '5': case '6': case '7': case '8': case '9':
+ CHECK_PAD('9', stringfunc_WIDTH);
+ pdesc->width = c - '0';
+ while (src < end_ptr && isdigit(src[1]))
+ pdesc->width = pdesc->width * 10 + *++src - '0';
+ break;
+ case '.':
+ if (src < end_ptr)
+ {
+ if (src[1] == '*')
+ {
+ CHECK_PAD('.', stringfunc_STAR_PRECISION);
+ src++;
+ }
+ else
+ {
+ /*
+ * when no one digit is entered, then precision
+ * is zero - digits are optional.
+ */
+ CHECK_PAD('.', stringfunc_PRECISION);
+ while (src < end_ptr && isdigit(src[1]))
+ {
+ pdesc->precision = pdesc->precision * 10 + *++src - '0';
+ }
+ }
+ }
+ else
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("broken sprintf format"),
+ errdetail("missing precision value")));
+ break;
+
+ default:
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("unsupported sprintf format tag '%.*s'", pg_mblen(src), src)));
+ }
+ }
+
+ if (pdesc->field_type == '\0')
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("broken sprintf format")));
+
+ return src;
+ }
+
+ static char *
+ currentFormat(StringInfo str, PlaceholderDesc pdesc)
+ {
+ resetStringInfo(str);
+ appendStringInfoChar(str,'%');
+
+ if (pdesc->flags & stringfunc_ZERO)
+ appendStringInfoChar(str, '0');
+
+ if (pdesc->flags & stringfunc_MINUS)
+ appendStringInfoChar(str, '-');
+
+ if (pdesc->flags & stringfunc_PLUS)
+ appendStringInfoChar(str, '+');
+
+ if (pdesc->flags & stringfunc_SPACE)
+ appendStringInfoChar(str, ' ');
+
+ if (pdesc->flags & stringfunc_SHARP)
+ appendStringInfoChar(str, '#');
+
+ if ((pdesc->flags & stringfunc_WIDTH) || (pdesc->flags & stringfunc_STAR_WIDTH))
+ appendStringInfoChar(str, '*');
+
+ if ((pdesc->flags & stringfunc_PRECISION) || (pdesc->flags & stringfunc_STAR_PRECISION))
+ appendStringInfoString(str, ".*");
+
+ /* Append l or ll. Decision is based on value of INT64_FORMAT */
+ if (pdesc->lenmod == 'l')
+ {
+ if (strcmp(INT64_FORMAT, "%lld") == 0)
+ appendStringInfoString(str, "ll");
+ else
+ appendStringInfoString(str, "l");
+ }
+ else if (pdesc->lenmod != '\0')
+ appendStringInfoChar(str, pdesc->lenmod);
+
+ appendStringInfoChar(str, pdesc->field_type);
+
+ return str->data;
+ }
+
+ /*
+ * simulate %+width.precion%s format of sprintf function
+ */
+ static void
+ append_string(StringInfo str, PlaceholderDesc pdesc, char *string)
+ {
+ int nchars = 0; /* length of substring in chars */
+ int binlen = 0; /* length of substring in bytes */
+
+ /*
+ * apply precision - it means "show only first n chars", for strings - this flag is
+ * ignored for proprietary tags %lq and iq, because we can't to show a first n chars
+ * from possible quoted value.
+ */
+ if (pdesc->flags & stringfunc_PRECISION && pdesc->field_type != 'q')
+ {
+ char *ptr = string;
+ int len = pdesc->precision;
+
+ if (pg_database_encoding_max_length() > 1)
+ {
+ while (*ptr && len > 0)
+ {
+ ptr += pg_mblen(ptr);
+ len--;
+ nchars++;
+ }
+ }
+ else
+ {
+ while (*ptr && len > 0)
+ {
+ ptr++;
+ len--;
+ nchars++;
+ }
+ }
+
+ binlen = ptr - string;
+ }
+ else
+ {
+ /* there isn't precion specified, show complete string */
+ nchars = pg_mbstrlen(string);
+ binlen = strlen(string);
+ }
+
+ /* when width is specified, then we have to solve left or right align */
+ if (pdesc->flags & stringfunc_WIDTH)
+ {
+ if (pdesc->width > nchars)
+ {
+ /* add neccessary spaces to begin or end */
+ if (pdesc->flags & stringfunc_MINUS)
+ {
+ /* allign to left */
+ appendBinaryStringInfo(str, string, binlen);
+ appendStringInfoSpaces(str, pdesc->width - nchars);
+ }
+ else
+ {
+ /* allign to right */
+ appendStringInfoSpaces(str, pdesc->width - nchars);
+ appendBinaryStringInfo(str, string, binlen);
+ }
+
+ }
+ else
+ /* just copy result to output */
+ appendBinaryStringInfo(str, string, binlen);
+ }
+ else
+ /* just copy result to output */
+ appendBinaryStringInfo(str, string, binlen);
+ }
+
+ /*
+ * Set width and precision when they are defined dynamicaly
+ */
+ static
+ int setWidthAndPrecision(PlaceholderDesc pdesc, FunctionCallInfoData *fcinfo, int current)
+ {
+
+ /*
+ * don't allow ambiguous definition
+ */
+ if ((pdesc->flags & stringfunc_WIDTH) && (pdesc->flags & stringfunc_STAR_WIDTH))
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("broken sprintf format"),
+ errdetail("ambiguous width definition")));
+
+ if ((pdesc->flags & stringfunc_PRECISION) && (pdesc->flags & stringfunc_STAR_PRECISION))
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("broken sprintf format"),
+ errdetail("ambiguous precision definition")));
+ if (pdesc->flags & stringfunc_STAR_WIDTH)
+ {
+ if (current >= PG_NARGS())
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("too few parameters specified for printf function")));
+
+ if (PG_ARGISNULL(current))
+ ereport(ERROR,
+ (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
+ errmsg("null value not allowed"),
+ errhint("width (%dth) arguments is NULL", current)));
+
+ pdesc->width = DatumGetInt32(castValueTo(PG_GETARG_DATUM(current), INT4OID,
+ get_fn_expr_argtype(fcinfo->flinfo, current)));
+ /* reset flag */
+ pdesc->flags ^= stringfunc_STAR_WIDTH;
+ pdesc->flags |= stringfunc_WIDTH;
+ current += 1;
+ }
+
+ if (pdesc->flags & stringfunc_STAR_PRECISION)
+ {
+ if (current >= PG_NARGS())
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("too few parameters specified for printf function")));
+
+ if (PG_ARGISNULL(current))
+ ereport(ERROR,
+ (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
+ errmsg("null value not allowed"),
+ errhint("width (%dth) arguments is NULL", current)));
+
+ pdesc->precision = DatumGetInt32(castValueTo(PG_GETARG_DATUM(current), INT4OID,
+ get_fn_expr_argtype(fcinfo->flinfo, current)));
+ /* reset flags */
+ pdesc->flags ^= stringfunc_STAR_PRECISION;
+ pdesc->flags |= stringfunc_PRECISION;
+ current += 1;
+ }
+
+ return current;
+ }
+
+ /*
+ * sprintf function - it is wrapper for libc vprintf function
+ *
+ * ensure PostgreSQL -> C casting
+ */
+ Datum
+ stringfunc_sprintf(PG_FUNCTION_ARGS)
+ {
+ text *fmt;
+ StringInfoData str;
+ StringInfoData format_str;
+ char *cp;
+ int i = 1;
+ size_t len;
+ char *start_ptr,
+ *end_ptr;
+ FormatPlaceholderData pdesc;
+ text *result;
+
+ Oid typoutput;
+ bool typIsVarlena;
+ Datum value;
+ Oid valtype;
+
+ /* When format string is null, returns null */
+ if (PG_ARGISNULL(0))
+ PG_RETURN_NULL();
+
+ fmt = PG_GETARG_TEXT_PP(0);
+ len = VARSIZE_ANY_EXHDR(fmt);
+ start_ptr = VARDATA_ANY(fmt);
+ end_ptr = start_ptr + len - 1;
+
+ initStringInfo(&str);
+ initStringInfo(&format_str);
+
+ for (cp = start_ptr; cp <= end_ptr; cp++)
+ {
+ if (cp[0] == '%')
+ {
+ /* when cp is not pointer on last char, check %% */
+ if (cp < end_ptr && cp[1] == '%')
+ {
+ appendStringInfoChar(&str, cp[1]);
+ cp++;
+ continue;
+ }
+
+ cp = parsePlaceholder(cp, end_ptr, &pdesc, fmt);
+ i = setWidthAndPrecision(&pdesc, fcinfo, i);
+
+ if (i >= PG_NARGS())
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("too few parameters specified for printf function")));
+
+ if (!PG_ARGISNULL(i))
+ {
+ /* append n-th value */
+ value = PG_GETARG_DATUM(i);
+ valtype = get_fn_expr_argtype(fcinfo->flinfo, i);
+
+ /* convert value to target type */
+ switch (pdesc.field_type)
+ {
+ case 'o': case 'd': case 'i': case 'x': case 'X':
+ {
+ int64 target_value;
+ const char *format;
+
+ pdesc.lenmod = 'l';
+ target_value = DatumGetInt64(castValueTo(value, INT8OID, valtype));
+ format = currentFormat(&format_str, &pdesc);
+
+ if ((pdesc.flags & stringfunc_WIDTH) && (pdesc.flags & stringfunc_PRECISION))
+ appendStringInfo(&str, format, pdesc.width, pdesc.precision, target_value);
+ else if (pdesc.flags & stringfunc_WIDTH)
+ appendStringInfo(&str, format, pdesc.width, target_value);
+ else if (pdesc.flags & stringfunc_PRECISION)
+ appendStringInfo(&str, format, pdesc.precision, target_value);
+ else
+ appendStringInfo(&str, format, target_value);
+ }
+ break;
+ case 'e': case 'f': case 'g': case 'G': case 'E':
+ {
+ float8 target_value;
+ const char *format;
+
+ target_value = DatumGetFloat8(castValueTo(value, FLOAT8OID, valtype));
+ format = currentFormat(&format_str, &pdesc);
+
+ if ((pdesc.flags & stringfunc_WIDTH) && (pdesc.flags & stringfunc_PRECISION))
+ appendStringInfo(&str, format, pdesc.width, pdesc.precision, target_value);
+ else if (pdesc.flags & stringfunc_WIDTH)
+ appendStringInfo(&str, format, pdesc.width, target_value);
+ else if (pdesc.flags & stringfunc_PRECISION)
+ appendStringInfo(&str, format, pdesc.precision, target_value);
+ else
+ appendStringInfo(&str, format, target_value);
+ }
+ break;
+ case 's':
+ {
+ char *target_value;
+
+ getTypeOutputInfo(valtype, &typoutput, &typIsVarlena);
+ target_value = OidOutputFunctionCall(typoutput, value);
+
+ append_string(&str, &pdesc, target_value);
+ pfree(target_value);
+ }
+ break;
+ default:
+ /* don't be happen - formats are checked in parsing stage */
+ elog(ERROR, "unknown format: %c", pdesc.field_type);
+ }
+ }
+ else
+ /* append a NULL string */
+ append_string(&str, &pdesc, "<NULL>");
+ i++;
+ }
+ else
+ appendStringInfoChar(&str, cp[0]);
+ }
+
+ /* check if all arguments are used */
+ if (i != PG_NARGS())
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("too many parameters for printf function")));
+ result = cstring_to_text_with_len(str.data, str.len);
+
+ pfree(str.data);
+ pfree(format_str.data);
+
+ PG_RETURN_TEXT_P(result);
+ }
+
+ /*
+ * only wrapper
+ */
+ Datum
+ stringfunc_sprintf_nv(PG_FUNCTION_ARGS)
+ {
+ return stringfunc_sprintf(fcinfo);
+ }
+
+ /*
+ * Substitute a positional parameters by value
+ */
+ Datum
+ stringfunc_substitute(PG_FUNCTION_ARGS)
+ {
+ text *fmt;
+ StringInfoData str;
+ char *cp;
+ size_t len;
+ char *start_ptr;
+ char *end_ptr;
+ text *result;
+ ArrayType *array;
+ Oid elmtype;
+ int16 elmlen;
+ bool elmbyval;
+ char elmalign;
+ int num_elems = 0;
+ Datum *elem_values;
+ bool *elem_nulls;
+
+ fmt = PG_GETARG_TEXT_PP(0);
+ len = VARSIZE_ANY_EXHDR(fmt);
+ start_ptr = VARDATA_ANY(fmt);
+ end_ptr = start_ptr + len - 1;
+
+ if (PG_NARGS() == 2)
+ {
+ array = PG_GETARG_ARRAYTYPE_P(1);
+ elmtype = ARR_ELEMTYPE(array);
+ get_typlenbyvalalign(elmtype, &elmlen, &elmbyval, &elmalign);
+
+ deconstruct_array(array, elmtype,
+ elmlen, elmbyval, elmalign,
+ &elem_values, &elem_nulls,
+ &num_elems);
+ }
+
+ initStringInfo(&str);
+ for (cp = start_ptr; cp <= end_ptr; cp++)
+ {
+ /*
+ * there are allowed escape char - '\'
+ */
+ if (cp[0] == '\\')
+ {
+ /* check next char */
+ if (cp < end_ptr)
+ {
+ switch (cp[1])
+ {
+ case '\\':
+ case '$':
+ appendStringInfoChar(&str, cp[1]);
+ break;
+
+ default:
+ /*
+ * because unsupported symbols should be a multibyte chars,
+ * we cannot to use a %c formating. We have take a complete
+ * multibyte char length and show it via %.*s.
+ */
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("unsuported escape sequence \"\\%.*s\"", pg_mblen(&cp[1]), &cp[1])));
+ }
+ cp++;
+ }
+ else
+ elog(ERROR, "broken escape sequence");
+ }
+ else if (cp[0] == '$')
+ {
+ long pos;
+ char *endptr;
+
+ /* initial check */
+ if (cp == end_ptr)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("missing a parameter position specification")));
+
+ if (!isdigit(cp[1]))
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("expected a numeric value")));
+
+ pos = strtol(&cp[1], &endptr, 10);
+ cp = endptr - 1;
+
+ if (pos < 1 || pos > num_elems)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("positional placeholder \"$%ld\" is not valid", pos)));
+
+ if (!elem_nulls[pos - 1])
+ appendStringInfoString(&str, text_to_cstring(DatumGetTextP(elem_values[pos - 1])));
+ else
+ appendStringInfoString(&str, "<NULL>");
+ }
+ else
+ appendStringInfoChar(&str, cp[0]);
+ }
+
+ result = cstring_to_text_with_len(str.data, str.len);
+ pfree(str.data);
+
+ PG_RETURN_TEXT_P(result);
+ }
+
+ /*
+ * Non variadic text_substitute function - only wrapper
+ * Print and check format string
+ */
+ Datum
+ stringfunc_substitute_nv(PG_FUNCTION_ARGS)
+ {
+ return stringfunc_substitute(fcinfo);
+ }
*** ./contrib/stringfunc/stringfunc.sql.in.orig 2010-09-29 08:12:51.329397362 +0200
--- ./contrib/stringfunc/stringfunc.sql.in 2010-09-29 08:10:48.366270806 +0200
***************
*** 0 ****
--- 1,25 ----
+ /* $PostgreSQL: pgsql/contrib/stringfunc/stringfunc.sql.in,v 1.25 2009/06/11 18:30:03 tgl Exp $ */
+
+ -- Adjust this setting to control where the objects get created.
+ SET search_path = public;
+
+ CREATE OR REPLACE FUNCTION sprintf(fmt text, VARIADIC args "any")
+ RETURNS text
+ AS '$libdir/stringfunc','stringfunc_sprintf'
+ LANGUAGE C STABLE;
+
+ CREATE OR REPLACE FUNCTION sprintf(fmt text)
+ RETURNS text
+ AS '$libdir/stringfunc','stringfunc_sprintf_nv'
+ LANGUAGE C STABLE;
+
+ CREATE OR REPLACE FUNCTION substitute(fmt text, VARIADIC args text[])
+ RETURNS text
+ AS '$libdir/stringfunc','stringfunc_substitute'
+ LANGUAGE C STABLE;
+
+ CREATE OR REPLACE FUNCTION substitute(fmt text)
+ RETURNS text
+ AS '$libdir/stringfunc','stringfunc_substitute_nv'
+ LANGUAGE C STABLE;
+
*** ./contrib/stringfunc/uninstall_stringfunc.sql.orig 2010-09-29 08:12:56.353273675 +0200
--- ./contrib/stringfunc/uninstall_stringfunc.sql 2010-09-29 08:10:48.366270806 +0200
***************
*** 0 ****
--- 1,10 ----
+ /* $PostgreSQL: pgsql/contrib/stringfunc/uninstall_stringfunc.sql,v 1.8 2008/04/14 17:05:32 tgl Exp $ */
+
+ -- Adjust this setting to control where the objects get dropped.
+ SET search_path = public;
+
+ DROP FUNCTION sprintf(fmt text, VARIADIC args "any");
+ DROP FUNCTION sprintf(fmt text);
+ DROP FUNCTION substitute(fmt text, VARIADIC args text[]);
+ DROP FUNCTION substitute(fmt text);
+
*** ./doc/src/sgml/contrib.sgml.orig 2010-09-29 08:10:11.529398663 +0200
--- ./doc/src/sgml/contrib.sgml 2010-09-29 08:10:48.367270236 +0200
***************
*** 115,120 ****
--- 115,121 ----
&seg;
&contrib-spi;
&sslinfo;
+ &stringfunc;
&tablefunc;
&test-parser;
&tsearch2;
*** ./doc/src/sgml/filelist.sgml.orig 2010-09-29 08:10:11.530395997 +0200
--- ./doc/src/sgml/filelist.sgml 2010-09-29 08:10:48.367270236 +0200
***************
*** 127,132 ****
--- 127,133 ----
<!entity seg SYSTEM "seg.sgml">
<!entity contrib-spi SYSTEM "contrib-spi.sgml">
<!entity sslinfo SYSTEM "sslinfo.sgml">
+ <!entity stringfunc SYSTEM "stringfunc.sgml">
<!entity tablefunc SYSTEM "tablefunc.sgml">
<!entity test-parser SYSTEM "test-parser.sgml">
<!entity tsearch2 SYSTEM "tsearch2.sgml">
*** ./doc/src/sgml/stringfunc.sgml.orig 2010-09-29 08:42:33.899272275 +0200
--- ./doc/src/sgml/stringfunc.sgml 2010-09-29 09:04:00.493270789 +0200
***************
*** 0 ****
--- 1,67 ----
+ <!-- $PostgreSQL: pgsql/doc/src/sgml/stringfunc.sgml,v 1.2 2008/09/12 18:29:49 tgl Exp $ -->
+
+ <sect1 id="stringfunc">
+ <title>stringfunc</title>
+
+ <indexterm zone="stringfunc">
+ <primary>stringfunc</primary>
+ </indexterm>
+
+ <para>
+ The <filename>stringfunc</> module provides a additional function
+ for operation over strings. These functions can be used as patter
+ for developing a variadic functions.
+ </para>
+
+ <sect2>
+ <title>How to Use It</title>
+
+ <para>
+ Here's a simple example of usage:
+
+ <programlisting>
+ SELECT sprintf('formated number: %10d',10);
+ SELECT substitute('file '$1' doesn''t exists', '/var/log/applog');
+ </programlisting>
+ </para>
+ </sect2>
+
+ <sect2>
+ <title><filename>stringfunc</> Functions and Operators</title>
+
+ <table id="stringfunc-func-table">
+ <title><filename>stringfunc</> Functions</title>
+
+ <tgroup cols="5">
+ <thead>
+ <row>
+ <entry>Function</entry>
+ <entry>Return Type</entry>
+ <entry>Description</entry>
+ <entry>Example</entry>
+ <entry>Result</entry>
+ </row>
+ </thead>
+
+ <tbody>
+ <row>
+ <entry><function>sprintf(formatstr [, params])</function></entry>
+ <entry><type>text</type></entry>
+ <entry>simplyfied version of libc sprintf function - it doesn't support
+ positional parameters and it will do necessary conversions automaticaly.</entry>
+ <entry><literal>sprintf('Hello %10s','World')</literal></entry>
+ <entry><literal>Hello World</literal></entry>
+ </row>
+
+ <row>
+ <entry><function>substitute(formatstr [, params])</function></entry>
+ <entry><type>text</type></entry>
+ <entry>replace a positional placeholers like $n by params</entry>
+ <entry><literal>substitute('$1,$2,$2,$1','A','B');</literal></entry>
+ <entry><literal>A,B,B,A</literal></entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+ </sect2>
+ </sect1>
--
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