*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/adt/char.c,v 1.19 1998/09/01 03:25:50 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/adt/char.c,v 1.20 1998/12/13 23:35:48 thomas Exp $
*
*-------------------------------------------------------------------------
*/
charin(char *ch)
{
if (ch == NULL)
- return (int32) NULL;
+ return (int32) '\0';
return (int32) *ch;
}
{
return arg1 == arg2;
}
+
+int8
+text_char(text *arg1)
+{
+ return ((int8) *(VARDATA(arg1)));
+}
+
+text *
+char_text(int8 arg1)
+{
+ text *result;
+
+ result = palloc(VARHDRSZ+1);
+ VARSIZE(result) = VARHDRSZ+1;
+ *(VARDATA(result)) = arg1;
+
+ return result;
+}
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/adt/varlena.c,v 1.45 1998/12/08 06:19:15 thomas Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/adt/varlena.c,v 1.46 1998/12/13 23:35:48 thomas Exp $
*
*-------------------------------------------------------------------------
*/
* - starting position (is one-based)
* - string length
*
- * If the starting position is zero or less, then return the entire string.
- * XXX Note that this may not be the right behavior:
- * if we are calculating the starting position we might want it to start at one.
+ * If the starting position is zero or less, then return from the start of the string
+ * adjusting the length to be consistant with the "negative start" per SQL92.
* If the length is less than zero, return the remaining string.
*
* Note that the arguments operate on octet length,
*
* Added multi-byte support.
* - Tatsuo Ishii 1998-4-21
+ * Changed behavior if starting position is less than one to conform to SQL92 behavior.
+ * Formerly returned the entire string; now returns a portion.
+ * - Thomas Lockhart 1998-12-10
*/
text *
text_substr(text *string, int32 m, int32 n)
#endif
- if ((string == (text *) NULL) || (m <= 0))
+ if (string == (text *) NULL)
return string;
len = VARSIZE(string) - VARHDRSZ;
len = pg_mbstrlen_with_len(VARDATA(string), len);
#endif
- /* m will now become a zero-based starting position */
+ /* starting position after the end of the string? */
if (m > len)
{
- m = 0;
+ m = 1;
n = 0;
}
- else
+ /* starting position before the start of the string?
+ * then offset into the string per SQL92 spec... */
+ else if (m < 1)
{
- m--;
- if (((m + n) > len) || (n < 0))
- n = (len - m);
+ n += (m-1);
+ m = 1;
}
+ /* m will now become a zero-based starting position */
+ m--;
+ if (((m + n) > len) || (n < 0))
+ n = (len - m);
+
#ifdef MULTIBYTE
p = VARDATA(string);
for (i = 0; i < m; i++)
*
* Copyright (c) 1994, Regents of the University of California
*
- * $Id: builtins.h,v 1.71 1998/12/08 06:18:34 thomas Exp $
+ * $Id: builtins.h,v 1.72 1998/12/13 23:36:48 thomas Exp $
*
* NOTES
* This should normally only be included by fmgr.h.
extern int8 charmul(int8 arg1, int8 arg2);
extern int8 chardiv(int8 arg1, int8 arg2);
extern bool cideq(int8 arg1, int8 arg2);
+extern int8 text_char(text *arg1);
+extern text* char_text(int8 arg1);
/* int.c */
extern int32 int2in(char *num);