database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-18 17:42:25 +03:00
Code Activity

Add routines to convert between varchar and bpchar.

Browse Source 
Add routines to allow sizing of varchar and bpchar into target columns.
This commit is contained in:
Thomas G. Lockhart
1998-05-09 22:45:14 +00:00
parent 9afe03355a
commit cb03826201
3 changed files with 143 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

127
src/backend/utils/adt/varchar.c
View File

@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/utils/adt/varchar.c,v 1.30 1998/04/27 17:08:26 scrappy Exp $
* $Header: /cvsroot/pgsql/src/backend/utils/adt/varchar.c,v 1.31 1998/05/09 22:42:07 thomas Exp $
*
*-------------------------------------------------------------------------
*/
@ -130,12 +130,103 @@ bpcharout(char *s)
return (result);
}
/* bpchar()
* Converts a char() type to a specific internal length.
* len is the length specified in () plus VARHDRSZ bytes.
*/
char *
bpchar(char *s, int32 len)
{
char *result,
*r;
int rlen, slen;
int i;
if (s == NULL)
return ((char *) NULL);
if ((len == -1) || (len == VARSIZE(s)))
return (s);
rlen = len - VARHDRSZ;
if (rlen > 4096)
elog(ERROR, "bpchar: length of char() must be less than 4096");
#ifdef STRINGDEBUG
printf("bpchar- convert string length %d (%d) ->%d (%d)\n",
VARSIZE(s)-VARHDRSZ, VARSIZE(s), rlen, len);
#endif
result = (char *) palloc(len);
VARSIZE(result) = len;
r = VARDATA(result);
slen = VARSIZE(s) - VARHDRSZ;
s = VARDATA(s);
#ifdef STRINGDEBUG
printf("bpchar- string is '");
#endif
for (i = 0; (i < rlen) && (i < slen); i++)
{
if (*s == '\0')
break;
#ifdef STRINGDEBUG
printf("%c", *s);
#endif
*r++ = *s++;
}
#ifdef STRINGDEBUG
printf("'\n");
#endif
/* blank pad the string if necessary */
for (; i < rlen; i++)
{
*r++ = ' ';
}
return (result);
} /* bpchar() */
/* bpchar_char()
* Convert bpchar(1) to char.
*/
int32
bpchar_char(char *s)
{
return ((int32) *VARDATA(s));
} /* char_bpchar() */
/* char_bpchar()
* Convert char to bpchar(1).
*/
char *
char_bpchar(int32 c)
{
char *result;
result = palloc(VARHDRSZ+1);
VARSIZE(result) = VARHDRSZ+1;
*(VARDATA(result)) = (char) c;
return result;
} /* char_bpchar() */
/*****************************************************************************
* varchar - varchar() *
*****************************************************************************/
/*
* vcharin -
* varcharin -
* converts a string of varchar() type to the internal representation.
* len is the length specified in () plus VARHDRSZ bytes. (XXX dummy is here
* because we pass typelem as the second argument for array_in.)
@ -193,6 +284,38 @@ varcharout(char *s)
return (result);
}
/* varchar()
* Converts a varchar() type to the specified size.
* slen is the length specified in () plus VARHDRSZ bytes.
*/
char *
varchar(char *s, int32 slen)
{
char *result;
int len;
if (s == NULL)
return ((char *) NULL);
len = VARSIZE(s);
if ((slen == -1) || (len <= slen))
return ((char *) s);
/* only reach here if we need to truncate string... */
len = slen - VARHDRSZ;
if (len > 4096)
elog(ERROR, "varchar: length of varchar() must be less than 4096");
result = (char *) palloc(slen);
VARSIZE(result) = slen;
strncpy(VARDATA(result), VARDATA(s), len);
return (result);
} /* varchar() */
/*****************************************************************************
* Comparison Functions used for bpchar
*****************************************************************************/