Files
openGauss-server/src/common/backend/utils/adt/a_compat.cpp
2024-11-06 16:04:39 +08:00

1070 lines
30 KiB
C++

/* -------------------------------------------------------------------------
* oracle_compat.c
* Oracle compatible functions.
*
* Copyright (c) 1996-2012, PostgreSQL Global Development Group
*
*
* IDENTIFICATION
* src/backend/utils/adt/oracle_compat.c
*
* -------------------------------------------------------------------------
*/
#include "postgres.h"
#include "knl/knl_variable.h"
#include "catalog/pg_proc.h"
#include "common/int.h"
#include "utils/builtins.h"
#include "utils/formatting.h"
#include "mb/pg_wchar.h"
#include "parser/parser.h"
#include "miscadmin.h"
static text* dotrim(const char* string, int stringlen, const char* set, int setlen, bool doltrim, bool dortrim);
/********************************************************************
*
* lower
*
* Syntax:
*
* text lower(text string)
*
* Purpose:
*
* Returns string, with all letters forced to lowercase.
*
********************************************************************/
Datum lower(PG_FUNCTION_ARGS)
{
text* in_string = PG_GETARG_TEXT_PP(0);
FUNC_CHECK_HUGE_POINTER(false, in_string, "lower()");
char* out_string = NULL;
text* result = NULL;
out_string = str_tolower(VARDATA_ANY(in_string), VARSIZE_ANY_EXHDR(in_string), PG_GET_COLLATION());
result = cstring_to_text(out_string);
pfree_ext(out_string);
PG_RETURN_TEXT_P(result);
}
/********************************************************************
*
* upper
*
* Syntax:
*
* text upper(text string)
*
* Purpose:
*
* Returns string, with all letters forced to uppercase.
*
********************************************************************/
Datum upper(PG_FUNCTION_ARGS)
{
text* in_string = PG_GETARG_TEXT_PP(0);
FUNC_CHECK_HUGE_POINTER(false, in_string, "upper()");
char* out_string = NULL;
text* result = NULL;
out_string = str_toupper(VARDATA_ANY(in_string), VARSIZE_ANY_EXHDR(in_string), PG_GET_COLLATION());
result = cstring_to_text(out_string);
pfree_ext(out_string);
PG_RETURN_TEXT_P(result);
}
/********************************************************************
*
* initcap
*
* Syntax:
*
* text initcap(text string)
*
* Purpose:
*
* Returns string, with first letter of each word in uppercase, all
* other letters in lowercase. A word is defined as a sequence of
* alphanumeric characters, delimited by non-alphanumeric
* characters.
*
********************************************************************/
Datum initcap(PG_FUNCTION_ARGS)
{
text* in_string = PG_GETARG_TEXT_PP(0);
char* out_string = NULL;
text* result = NULL;
FUNC_CHECK_HUGE_POINTER(false, in_string, "initcap()");
out_string = str_initcap(VARDATA_ANY(in_string), VARSIZE_ANY_EXHDR(in_string), PG_GET_COLLATION());
result = cstring_to_text(out_string);
pfree_ext(out_string);
PG_RETURN_TEXT_P(result);
}
/********************************************************************
*
* nls_initcap
*
* Syntax:
*
* text nls_initcap(text string)
*
* Purpose:
*
* Returns string, with first letter of each word in uppercase, all
* other letters in lowercase. A word is defined as a sequence of
* alphanumeric characters, delimited by non-alphanumeric
* characters.
*
********************************************************************/
Datum nls_initcap(PG_FUNCTION_ARGS)
{
text* in_string = PG_GETARG_TEXT_PP(0);
if (!PG_ARGISNULL(1)) {
ereport(NOTICE,
(errcode(ERRCODE_OPERATE_INVALID_PARAM),
errmsg("The second parameter of this function will not take effect.")));
}
char* out_string = NULL;
text* result = NULL;
FUNC_CHECK_HUGE_POINTER(false, in_string, "nls_initcap()");
out_string = str_initcap(VARDATA_ANY(in_string), VARSIZE_ANY_EXHDR(in_string), PG_GET_COLLATION());
result = cstring_to_text(out_string);
pfree_ext(out_string);
PG_RETURN_TEXT_P(result);
}
/********************************************************************
*
* lpad
*
* Syntax:
*
* text lpad(text string1, int4 len, text string2)
*
* Purpose:
*
* Returns string1, left-padded to length len with the sequence of
* characters in string2. If len is less than the length of string1,
* instead truncate (on the right) to len.
*
********************************************************************/
Datum lpad(PG_FUNCTION_ARGS)
{
text* string1 = PG_GETARG_TEXT_PP(0);
int32 len = PG_GETARG_INT32(1);
text* string2 = PG_GETARG_TEXT_PP(2);
text* ret = NULL;
char *ptr1 = NULL, *ptr2 = NULL, *ptr2start = NULL, *ptr2end = NULL, *ptr_ret = NULL;
int m, s1len, s2len;
int bytelen;
errno_t ss_rc;
FUNC_CHECK_HUGE_POINTER(false, string1, "lpad()");
/* Negative len is silently taken as zero */
if (len < 0)
len = 0;
s1len = VARSIZE_ANY_EXHDR(string1);
if (s1len < 0)
s1len = 0; /* shouldn't happen */
s2len = VARSIZE_ANY_EXHDR(string2);
if (s2len < 0)
s2len = 0; /* shouldn't happen */
s1len = pg_mbstrlen_with_len(VARDATA_ANY(string1), s1len);
if (s1len > len)
s1len = len; /* truncate string1 to len chars */
if (s2len <= 0)
len = s1len; /* nothing to pad with, so don't pad */
bytelen = pg_database_encoding_max_length() * len;
/* check for integer overflow */
if (len != 0 && bytelen / pg_database_encoding_max_length() != len)
ereport(ERROR, (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED), errmsg("requested length too large")));
ret = (text*)palloc(VARHDRSZ + bytelen);
m = len - s1len;
ptr2 = ptr2start = VARDATA_ANY(string2);
ptr2end = ptr2 + s2len;
ptr_ret = VARDATA(ret);
int tmp_len = 0;
while (m--) {
int mlen = pg_mblen(ptr2);
ss_rc = memcpy_s(ptr_ret, bytelen - tmp_len, ptr2, mlen);
securec_check(ss_rc, "\0", "\0");
ptr_ret += mlen;
tmp_len += mlen;
ptr2 += mlen;
if (ptr2 == ptr2end) /* wrap around at end of s2 */
ptr2 = ptr2start;
}
ptr1 = VARDATA_ANY(string1);
tmp_len = 0;
while (s1len--) {
int mlen = pg_mblen(ptr1);
ss_rc = memcpy_s(ptr_ret, bytelen - tmp_len, ptr1, mlen);
securec_check(ss_rc, "\0", "\0");
ptr_ret += mlen;
tmp_len += mlen;
ptr1 += mlen;
}
SET_VARSIZE(ret, ptr_ret - (char*)ret);
if (0 == VARSIZE_ANY_EXHDR(ret) && u_sess->attr.attr_sql.sql_compatibility == A_FORMAT &&
!ACCEPT_EMPTY_STR && !RETURN_NS)
PG_RETURN_NULL();
else
PG_RETURN_TEXT_P(ret);
}
/********************************************************************
*
* rpad
*
* Syntax:
*
* text rpad(text string1, int4 len, text string2)
*
* Purpose:
*
* Returns string1, right-padded to length len with the sequence of
* characters in string2. If len is less than the length of string1,
* instead truncate (on the right) to len.
*
********************************************************************/
Datum rpad(PG_FUNCTION_ARGS)
{
text* string1 = PG_GETARG_TEXT_PP(0);
int32 len = PG_GETARG_INT32(1);
text* string2 = PG_GETARG_TEXT_PP(2);
text* ret = NULL;
char *ptr1 = NULL, *ptr2 = NULL, *ptr2start = NULL, *ptr2end = NULL, *ptr_ret = NULL;
int m, s1len, s2len;
FUNC_CHECK_HUGE_POINTER(false, string1, "rpad()");
int bytelen;
errno_t ss_rc;
/* Negative len is silently taken as zero */
if (len < 0)
len = 0;
s1len = VARSIZE_ANY_EXHDR(string1);
if (s1len < 0)
s1len = 0; /* shouldn't happen */
s2len = VARSIZE_ANY_EXHDR(string2);
if (s2len < 0)
s2len = 0; /* shouldn't happen */
s1len = pg_mbstrlen_with_len(VARDATA_ANY(string1), s1len);
if (s1len > len)
s1len = len; /* truncate string1 to len chars */
if (s2len <= 0)
len = s1len; /* nothing to pad with, so don't pad */
bytelen = pg_database_encoding_max_length() * len;
/* Check for integer overflow */
if (len != 0 && bytelen / pg_database_encoding_max_length() != len)
ereport(ERROR, (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED), errmsg("requested length too large")));
ret = (text*)palloc(VARHDRSZ + bytelen);
m = len - s1len;
ptr1 = VARDATA_ANY(string1);
ptr_ret = VARDATA(ret);
int tmp_len = 0;
while (s1len--) {
int mlen = pg_mblen(ptr1);
ss_rc = memcpy_s(ptr_ret, bytelen - tmp_len, ptr1, mlen);
securec_check(ss_rc, "\0", "\0");
ptr_ret += mlen;
tmp_len += mlen;
ptr1 += mlen;
}
ptr2 = ptr2start = VARDATA_ANY(string2);
ptr2end = ptr2 + s2len;
tmp_len = 0;
while (m--) {
int mlen = pg_mblen(ptr2);
ss_rc = memcpy_s(ptr_ret, bytelen - tmp_len, ptr2, mlen);
securec_check(ss_rc, "\0", "\0");
ptr_ret += mlen;
tmp_len += mlen;
ptr2 += mlen;
if (ptr2 == ptr2end) /* wrap around at end of s2 */
ptr2 = ptr2start;
}
SET_VARSIZE(ret, ptr_ret - (char*)ret);
if (0 == VARSIZE_ANY_EXHDR(ret) && u_sess->attr.attr_sql.sql_compatibility == A_FORMAT &&
!ACCEPT_EMPTY_STR && !RETURN_NS)
PG_RETURN_NULL();
else
PG_RETURN_TEXT_P(ret);
}
/********************************************************************
*
* btrim
*
* Syntax:
*
* text btrim(text string, text set)
*
* Purpose:
*
* Returns string with characters removed from the front and back
* up to the first character not in set.
*
********************************************************************/
Datum btrim(PG_FUNCTION_ARGS)
{
text* string = PG_GETARG_TEXT_PP(0);
text* set = PG_GETARG_TEXT_PP(1);
text* ret = NULL;
FUNC_CHECK_HUGE_POINTER(false, string, "btrim()");
ret = dotrim(VARDATA_ANY(string), VARSIZE_ANY_EXHDR(string), VARDATA_ANY(set), VARSIZE_ANY_EXHDR(set), true, true);
if ((ret == NULL || 0 == VARSIZE_ANY_EXHDR(ret)) && u_sess->attr.attr_sql.sql_compatibility == A_FORMAT &&
!ACCEPT_EMPTY_STR)
PG_RETURN_NULL();
else
PG_RETURN_TEXT_P(ret);
}
/********************************************************************
*
* btrim1 --- btrim with set fixed as ' '
*
********************************************************************/
Datum btrim1(PG_FUNCTION_ARGS)
{
text* string = PG_GETARG_TEXT_PP(0);
text* ret = NULL;
FUNC_CHECK_HUGE_POINTER(false, string, "btrim1()");
ret = dotrim(VARDATA_ANY(string), VARSIZE_ANY_EXHDR(string), " ", 1, true, true);
if ((ret == NULL || 0 == VARSIZE_ANY_EXHDR(ret)) && u_sess->attr.attr_sql.sql_compatibility == A_FORMAT &&
!ACCEPT_EMPTY_STR)
PG_RETURN_NULL();
else
PG_RETURN_TEXT_P(ret);
}
/*
* Common implementation for btrim, ltrim, rtrim
*/
static text* dotrim(const char* string, int stringlen, const char* set, int setlen, bool doltrim, bool dortrim)
{
int i;
/* Nothing to do if either string or set is empty */
if (stringlen > 0 && setlen > 0) {
if (pg_database_encoding_max_length() > 1) {
/*
* In the multibyte-encoding case, build arrays of pointers to
* character starts, so that we can avoid inefficient checks in
* the inner loops.
*/
const char** stringchars;
const char** setchars;
int* stringmblen = NULL;
int* setmblen = NULL;
int stringnchars;
int setnchars;
int resultndx;
int resultnchars;
const char* p = NULL;
int len;
int mblen;
const char* str_pos = NULL;
int str_len;
stringchars = (const char**)palloc(stringlen * sizeof(char*));
stringmblen = (int*)palloc(stringlen * sizeof(int));
stringnchars = 0;
p = string;
len = stringlen;
while (len > 0) {
stringchars[stringnchars] = p;
stringmblen[stringnchars] = mblen = pg_mblen(p);
stringnchars++;
p += mblen;
len -= mblen;
}
setchars = (const char**)palloc(setlen * sizeof(char*));
setmblen = (int*)palloc(setlen * sizeof(int));
setnchars = 0;
p = set;
len = setlen;
while (len > 0) {
setchars[setnchars] = p;
setmblen[setnchars] = mblen = pg_mblen(p);
setnchars++;
p += mblen;
len -= mblen;
}
resultndx = 0; /* index in stringchars[] */
resultnchars = stringnchars;
if (doltrim) {
while (resultnchars > 0) {
str_pos = stringchars[resultndx];
str_len = stringmblen[resultndx];
for (i = 0; i < setnchars; i++) {
if (str_len == setmblen[i] && memcmp(str_pos, setchars[i], str_len) == 0)
break;
}
if (i >= setnchars)
break; /* no match here */
string += str_len;
stringlen -= str_len;
resultndx++;
resultnchars--;
}
}
if (dortrim) {
while (resultnchars > 0) {
str_pos = stringchars[resultndx + resultnchars - 1];
str_len = stringmblen[resultndx + resultnchars - 1];
for (i = 0; i < setnchars; i++) {
if (str_len == setmblen[i] && memcmp(str_pos, setchars[i], str_len) == 0)
break;
}
if (i >= setnchars)
break; /* no match here */
stringlen -= str_len;
resultnchars--;
}
}
pfree_ext(stringchars);
pfree_ext(stringmblen);
pfree_ext(setchars);
pfree_ext(setmblen);
} else {
/*
* In the single-byte-encoding case, we don't need such overhead.
*/
if (doltrim) {
while (stringlen > 0) {
char str_ch = *string;
for (i = 0; i < setlen; i++) {
if (str_ch == set[i])
break;
}
if (i >= setlen)
break; /* no match here */
string++;
stringlen--;
}
}
if (dortrim) {
while (stringlen > 0) {
char str_ch = string[stringlen - 1];
for (i = 0; i < setlen; i++) {
if (str_ch == set[i])
break;
}
if (i >= setlen)
break; /* no match here */
stringlen--;
}
}
}
}
/* Return selected portion of string */
return cstring_to_text_with_len(string, stringlen);
}
/********************************************************************
*
* byteatrim
*
* Syntax:
*
* bytea byteatrim(byta string, bytea set)
*
* Purpose:
*
* Returns string with characters removed from the front and back
* up to the first character not in set.
*
* Cloned from btrim and modified as required.
********************************************************************/
Datum byteatrim(PG_FUNCTION_ARGS)
{
bytea* string = PG_GETARG_BYTEA_PP(0);
bytea* set = PG_GETARG_BYTEA_PP(1);
bytea* ret = NULL;
char *ptr = NULL, *end = NULL, *ptr2 = NULL, *ptr2start = NULL, *end2 = NULL;
int m, stringlen, setlen;
FUNC_CHECK_HUGE_POINTER(false, string, "byteatrim()");
stringlen = VARSIZE_ANY_EXHDR(string);
setlen = VARSIZE_ANY_EXHDR(set);
if (stringlen <= 0 || setlen <= 0)
PG_RETURN_BYTEA_P(string);
m = stringlen;
ptr = VARDATA_ANY(string);
end = ptr + stringlen - 1;
ptr2start = VARDATA_ANY(set);
end2 = ptr2start + setlen - 1;
while (m > 0) {
ptr2 = ptr2start;
while (ptr2 <= end2) {
if (*ptr == *ptr2)
break;
++ptr2;
}
if (ptr2 > end2)
break;
ptr++;
m--;
}
while (m > 0) {
ptr2 = ptr2start;
while (ptr2 <= end2) {
if (*end == *ptr2)
break;
++ptr2;
}
if (ptr2 > end2)
break;
end--;
m--;
}
ret = (bytea*)palloc(VARHDRSZ + m);
SET_VARSIZE(ret, VARHDRSZ + m);
if (m > 0) {
errno_t ss_rc = memcpy_s(VARDATA(ret), m, ptr, m);
securec_check(ss_rc, "\0", "\0");
}
PG_RETURN_BYTEA_P(ret);
}
/********************************************************************
*
* ltrim
*
* Syntax:
*
* text ltrim(text string, text set)
*
* Purpose:
*
* Returns string with initial characters removed up to the first
* character not in set.
*
********************************************************************/
Datum ltrim(PG_FUNCTION_ARGS)
{
text* string = PG_GETARG_TEXT_PP(0);
text* set = PG_GETARG_TEXT_PP(1);
text* ret = NULL;
FUNC_CHECK_HUGE_POINTER(false, string, "ltrim()");
ret = dotrim(VARDATA_ANY(string), VARSIZE_ANY_EXHDR(string), VARDATA_ANY(set), VARSIZE_ANY_EXHDR(set), true, false);
if ((ret == NULL || 0 == VARSIZE_ANY_EXHDR(ret)) && u_sess->attr.attr_sql.sql_compatibility == A_FORMAT &&
!ACCEPT_EMPTY_STR)
PG_RETURN_NULL();
else
PG_RETURN_TEXT_P(ret);
}
/********************************************************************
*
* ltrim1 --- ltrim with set fixed as ' '
*
********************************************************************/
Datum ltrim1(PG_FUNCTION_ARGS)
{
text* string = PG_GETARG_TEXT_PP(0);
text* ret = NULL;
FUNC_CHECK_HUGE_POINTER(false, string, "ltrim1()");
ret = dotrim(VARDATA_ANY(string), VARSIZE_ANY_EXHDR(string), " ", 1, true, false);
if ((ret == NULL || 0 == VARSIZE_ANY_EXHDR(ret)) && u_sess->attr.attr_sql.sql_compatibility == A_FORMAT &&
!ACCEPT_EMPTY_STR)
PG_RETURN_NULL();
else
PG_RETURN_TEXT_P(ret);
}
/********************************************************************
*
* rtrim
*
* Syntax:
*
* text rtrim(text string, text set)
*
* Purpose:
*
* Returns string with final characters removed after the last
* character not in set.
*
********************************************************************/
Datum rtrim(PG_FUNCTION_ARGS)
{
text* string = PG_GETARG_TEXT_PP(0);
text* set = PG_GETARG_TEXT_PP(1);
text* ret = NULL;
FUNC_CHECK_HUGE_POINTER(false, string, "rtrim()");
ret = dotrim(VARDATA_ANY(string), VARSIZE_ANY_EXHDR(string), VARDATA_ANY(set), VARSIZE_ANY_EXHDR(set), false, true);
if ((ret == NULL || 0 == VARSIZE_ANY_EXHDR(ret)) && u_sess->attr.attr_sql.sql_compatibility == A_FORMAT &&
!ACCEPT_EMPTY_STR)
PG_RETURN_NULL();
else
PG_RETURN_TEXT_P(ret);
}
/********************************************************************
*
* rtrim1 --- rtrim with set fixed as ' '
*
********************************************************************/
Datum rtrim1(PG_FUNCTION_ARGS)
{
text* string = PG_GETARG_TEXT_PP(0);
text* ret = NULL;
FUNC_CHECK_HUGE_POINTER(false, string, "rtrim1");
if (u_sess->attr.attr_sql.sql_compatibility == A_FORMAT && CHAR_COERCE_COMPAT
&& fcinfo->flinfo && fcinfo->flinfo->fn_oid == RTRIM1FUNCOID) {
/*
* char(n) will not ignore the tailing blanks in A_FORMAT compatibility.
* here, we just return original input.
*/
PG_RETURN_TEXT_P(string);
} else {
ret = dotrim(VARDATA_ANY(string), VARSIZE_ANY_EXHDR(string), " ", 1, false, true);
}
if ((ret == NULL || 0 == VARSIZE_ANY_EXHDR(ret)) && u_sess->attr.attr_sql.sql_compatibility == A_FORMAT &&
!ACCEPT_EMPTY_STR)
PG_RETURN_NULL();
else
PG_RETURN_TEXT_P(ret);
}
/********************************************************************
*
* translate
*
* Syntax:
*
* text translate(text string, text from, text to)
*
* Purpose:
*
* Returns string after replacing all occurrences of characters in from
* with the corresponding character in to. If from is longer than to,
* occurrences of the extra characters in from are deleted.
* Improved by Edwin Ramirez <ramirez@doc.mssm.edu>.
*
********************************************************************/
Datum translate(PG_FUNCTION_ARGS)
{
text* string = PG_GETARG_TEXT_PP(0);
text* from = PG_GETARG_TEXT_PP(1);
text* to = PG_GETARG_TEXT_PP(2);
text* result = NULL;
char *from_ptr = NULL, *to_ptr = NULL;
char *source = NULL, *target = NULL;
int m, fromlen, tolen, retlen, i;
int worst_len;
int len;
int source_len;
int from_index;
errno_t ss_rc;
FUNC_CHECK_HUGE_POINTER(false, string, "translate()");
m = VARSIZE_ANY_EXHDR(string);
if (m <= 0)
PG_RETURN_TEXT_P(string);
source = VARDATA_ANY(string);
fromlen = VARSIZE_ANY_EXHDR(from);
from_ptr = VARDATA_ANY(from);
tolen = VARSIZE_ANY_EXHDR(to);
to_ptr = VARDATA_ANY(to);
/*
* The worst-case expansion is to substitute a max-length character for a
* single-byte character at each position of the string.
*/
worst_len = pg_database_encoding_max_length() * m;
/* check for integer overflow */
if (worst_len / pg_database_encoding_max_length() != m)
ereport(ERROR, (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED), errmsg("requested length too large")));
result = (text*)palloc(worst_len + VARHDRSZ);
target = VARDATA(result);
retlen = 0;
int tmp_len = 0;
while (m > 0) {
source_len = pg_mblen(source);
from_index = 0;
for (i = 0; i < fromlen; i += len) {
len = pg_mblen(&from_ptr[i]);
if (len == source_len && memcmp(source, &from_ptr[i], len) == 0)
break;
from_index++;
}
if (i < fromlen) {
/* substitute */
char* p = to_ptr;
for (i = 0; i < from_index; i++) {
p += pg_mblen(p);
if (p >= (to_ptr + tolen))
break;
}
if (p < (to_ptr + tolen)) {
len = pg_mblen(p);
ss_rc = memcpy_s(target, worst_len - tmp_len, p, len);
securec_check(ss_rc, "\0", "\0");
target += len;
tmp_len += len;
retlen += len;
}
} else {
/* no match, so copy */
ss_rc = memcpy_s(target, worst_len - tmp_len, source, source_len);
securec_check(ss_rc, "\0", "\0");
target += source_len;
tmp_len += source_len;
retlen += source_len;
}
source += source_len;
m -= source_len;
}
if (0 == retlen && u_sess->attr.attr_sql.sql_compatibility == A_FORMAT && !ACCEPT_EMPTY_STR) {
PG_RETURN_NULL();
} else {
SET_VARSIZE(result, retlen + VARHDRSZ);
/*
* The function result is probably much bigger than needed, if we're using
* a multibyte encoding, but it's not worth reallocating it; the result
* probably won't live long anyway.
*/
PG_RETURN_TEXT_P(result);
}
}
/********************************************************************
*
* ascii
*
* Syntax:
*
* int ascii(text string)
*
* Purpose:
*
* Returns the decimal representation of the first character from
* string.
* If the string is empty we return 0.
* If the database encoding is UTF8, we return the Unicode codepoint.
* If the database encoding is any other multi-byte encoding, we
* return the value of the first byte if it is an ASCII character
* (range 1 .. 127), or raise an error.
* For all other encodings we return the value of the first byte,
* (range 1..255).
*
********************************************************************/
Datum ascii(PG_FUNCTION_ARGS)
{
text* string = PG_GETARG_TEXT_PP(0);
int encoding = GetDatabaseEncoding();
unsigned char* data = NULL;
FUNC_CHECK_HUGE_POINTER(false, string, "ascii()");
if (VARSIZE_ANY_EXHDR(string) <= 0)
PG_RETURN_INT32(0);
data = (unsigned char*)VARDATA_ANY(string);
if (encoding == PG_UTF8 && *data > 127) {
/* return the code point for Unicode */
int result = 0, tbytes = 0, i;
if (*data >= 0xF0) {
result = *data & 0x07;
tbytes = 3;
} else if (*data >= 0xE0) {
result = *data & 0x0F;
tbytes = 2;
} else {
Assert(*data > 0xC0);
result = *data & 0x1f;
tbytes = 1;
}
Assert(tbytes > 0);
for (i = 1; i <= tbytes; i++) {
if ((data[i] & 0xC0) != 0x80) {
report_invalid_encoding(PG_UTF8, (const char*)data, tbytes);
} else {
result = (result << 6) + (data[i] & 0x3f);
}
}
PG_RETURN_INT32(result);
} else {
if (pg_encoding_max_length(encoding) > 1 && *data > 127)
ereport(ERROR, (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED), errmsg("requested character too large")));
PG_RETURN_INT32((int32)*data);
}
}
/********************************************************************
*
* chr
*
* Syntax:
*
* text chr(int val)
*
* Purpose:
*
* Returns the character having the binary equivalent to val.
*
* For UTF8 we treat the argumwent as a Unicode code point.
* For other multi-byte encodings we raise an error for arguments
* outside the strict ASCII range (1..127).
*
* It's important that we don't ever return a value that is not valid
* in the database encoding, so that this doesn't become a way for
* invalid data to enter the database.
*
********************************************************************/
Datum chr(PG_FUNCTION_ARGS)
{
uint32 cvalue = PG_GETARG_UINT32(0);
text* result = NULL;
int encoding = GetDatabaseEncoding();
if (encoding == PG_UTF8 && cvalue > 127) {
/* for Unicode we treat the argument as a code point */
int bytes;
char* wch = NULL;
/* We only allow valid Unicode code points */
if (cvalue > 0x001fffff)
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("requested character too large for encoding: %u", cvalue)));
if (cvalue > 0xffff)
bytes = 4;
else if (cvalue > 0x07ff)
bytes = 3;
else
bytes = 2;
result = (text*)palloc(VARHDRSZ + bytes);
SET_VARSIZE(result, VARHDRSZ + bytes);
wch = VARDATA(result);
if (bytes == 2) {
wch[0] = 0xC0 | ((cvalue >> 6) & 0x1F);
wch[1] = 0x80 | (cvalue & 0x3F);
} else if (bytes == 3) {
wch[0] = 0xE0 | ((cvalue >> 12) & 0x0F);
wch[1] = 0x80 | ((cvalue >> 6) & 0x3F);
wch[2] = 0x80 | (cvalue & 0x3F);
} else {
wch[0] = 0xF0 | ((cvalue >> 18) & 0x07);
wch[1] = 0x80 | ((cvalue >> 12) & 0x3F);
wch[2] = 0x80 | ((cvalue >> 6) & 0x3F);
wch[3] = 0x80 | (cvalue & 0x3F);
}
} else if (encoding == PG_GBK && u_sess->attr.attr_sql.sql_compatibility == A_FORMAT) {
unsigned char bytes[2];
char* wch = NULL;
if (cvalue > 0xfefe)
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("requested character too large for encoding: %u", cvalue)));
for (int i = 0; i < 2; i++) {
bytes[i] = (cvalue >> ((1 - i) * 8)) & 0xFF;
}
if (!pg_gbk_islegal(bytes, 2))
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("invalid character length for encoding: %u", cvalue)));
result = (text*)palloc(VARHDRSZ + 2);
SET_VARSIZE(result, VARHDRSZ + 2);
wch = VARDATA(result);
wch[0] = (char)bytes[0];
wch[1] = (char)bytes[1];
} else {
bool is_mb = false;
/*
* Error out on arguments that make no sense or that we can't validly
* represent in the encoding.
*/
if (cvalue == 0)
PG_RETURN_NULL();
is_mb = pg_encoding_max_length(encoding) > 1;
if ((is_mb && (cvalue > 127)) || (!is_mb && (cvalue > 255)))
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("requested character too large for encoding: %u", cvalue)));
result = (text*)palloc(VARHDRSZ + 1);
SET_VARSIZE(result, VARHDRSZ + 1);
*VARDATA(result) = (char)cvalue;
}
PG_RETURN_TEXT_P(result);
}
/********************************************************************
*
* repeat
*
* Syntax:
*
* text repeat(text string, int val)
*
* Purpose:
*
* Repeat string by val.
*
********************************************************************/
Datum repeat(PG_FUNCTION_ARGS)
{
text* string = PG_GETARG_TEXT_PP(0);
int32 count = PG_GETARG_INT32(1);
FUNC_CHECK_HUGE_POINTER(false, string, "repeat()");
text* result = NULL;
int slen, tlen;
int i;
char *cp = NULL, *sp = NULL;
if (count < 0)
count = 0;
slen = VARSIZE_ANY_EXHDR(string);
if (unlikely(pg_mul_s32_overflow(count, slen, &tlen)) || unlikely(pg_add_s32_overflow(tlen, VARHDRSZ, &tlen)))
ereport(ERROR, (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED), errmsg("requested length too large")));
result = (text*)palloc(tlen);
SET_VARSIZE(result, tlen);
cp = VARDATA(result);
sp = VARDATA_ANY(string);
for (i = 0; i < count; i++) {
errno_t ss_rc = memcpy_s(cp, tlen, sp, slen);
securec_check(ss_rc, "\0", "\0");
cp += slen;
tlen -= slen;
}
if (0 == VARSIZE_ANY_EXHDR(result) && u_sess->attr.attr_sql.sql_compatibility == A_FORMAT &&
!ACCEPT_EMPTY_STR && !RETURN_NS) {
PG_RETURN_NULL();
} else
PG_RETURN_TEXT_P(result);
}