ltree 支持的字符 ISALNUM
背景
ltree目前只支持alpha numeric,数字,字母,下划线。
postgres=# select text2ltree('abc.\<f');
ERROR: 42601: syntax error at position 4
LOCATION: ltree_in, ltree_io.c:81
postgres=# select text2ltree('abc._f');
text2ltree
------------
abc._f
(1 row)
见代码ltree_in.
参考
1. contrib/ltree/ltree_io.c
#include <ctype.h>
......
Datum
ltree_in(PG_FUNCTION_ARGS)
{
char *buf = (char *) PG_GETARG_POINTER(0);
char *ptr;
nodeitem *list,
*lptr;
int num = 0,
totallen = 0;
int state = LTPRS_WAITNAME;
ltree *result;
ltree_level *curlevel;
int charlen;
int pos = 0;
ptr = buf;
while (*ptr)
{
charlen = pg_mblen(ptr);
if (charlen == 1 && t_iseq(ptr, '.'))
num++;
ptr += charlen;
}
if (num + 1 > MaxAllocSize / sizeof(nodeitem))
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("number of levels (%d) exceeds the maximum allowed (%d)",
num + 1, (int) (MaxAllocSize / sizeof(nodeitem)))));
list = lptr = (nodeitem *) palloc(sizeof(nodeitem) * (num + 1));
ptr = buf;
while (*ptr)
{
charlen = pg_mblen(ptr);
if (state == LTPRS_WAITNAME)
{
if (ISALNUM(ptr))
{
lptr->start = ptr;
lptr->wlen = 0;
state = LTPRS_WAITDELIM;
}
else
UNCHAR;
}
else if (state == LTPRS_WAITDELIM)
{
if (charlen == 1 && t_iseq(ptr, '.'))
{
lptr->len = ptr - lptr->start;
if (lptr->wlen > 255)
ereport(ERROR,
(errcode(ERRCODE_NAME_TOO_LONG),
errmsg("name of level is too long"),
errdetail("Name length is %d, must "
"be < 256, in position %d.",
lptr->wlen, pos)));
totallen += MAXALIGN(lptr->len + LEVEL_HDRSIZE);
lptr++;
state = LTPRS_WAITNAME;
}
else if (!ISALNUM(ptr))
UNCHAR;
}
else
/* internal error */
elog(ERROR, "internal error in parser");
ptr += charlen;
lptr->wlen++;
pos++;
}
if (state == LTPRS_WAITDELIM)
{
lptr->len = ptr - lptr->start;
if (lptr->wlen > 255)
ereport(ERROR,
(errcode(ERRCODE_NAME_TOO_LONG),
errmsg("name of level is too long"),
errdetail("Name length is %d, must "
"be < 256, in position %d.",
lptr->wlen, pos)));
totallen += MAXALIGN(lptr->len + LEVEL_HDRSIZE);
lptr++;
}
else if (!(state == LTPRS_WAITNAME && lptr == list))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("syntax error"),
errdetail("Unexpected end of line.")));
result = (ltree *) palloc0(LTREE_HDRSIZE + totallen);
SET_VARSIZE(result, LTREE_HDRSIZE + totallen);
result->numlevel = lptr - list;
curlevel = LTREE_FIRST(result);
lptr = list;
while (lptr - list < result->numlevel)
{
curlevel->len = (uint16) lptr->len;
memcpy(curlevel->name, lptr->start, lptr->len);
curlevel = LEVEL_NEXT(curlevel);
lptr++;
}
pfree(list);
PG_RETURN_POINTER(result);
}