In the following code from hstore_io.c, is HStore a varlena? In which case is
the following code buggy because it omits to subtract VARHDRSZ from in->size
and therefore is not handling the empty hstore and also starting the loop from
the varlena header instead of the first data byte?
Or if HStore is not a varlena then PG_GETARG_HS is buggy since it calls
PG_DETOAST_DATUM() on the argument.
PG_FUNCTION_INFO_V1(hstore_out);
Datum hstore_out(PG_FUNCTION_ARGS);
Datum
hstore_out(PG_FUNCTION_ARGS)
{HStore *in = PG_GETARG_HS(0);int buflen, i;char *out, *ptr;char
*base= STRPTR(in);HEntry *entries = ARRPTR(in);
if (in->size == 0){ out = palloc(1); *out = '\0'; PG_FREE_IF_COPY(in, 0); PG_RETURN_CSTRING(out);}
buflen = (4 /* " */ + 2 /* => */ + 2 /* , */ ) * in->size + 2 /* esc */ * (in->len - CALCDATASIZE(in->size, 0));
out = ptr = palloc(buflen);for (i = 0; i < in->size; i++){ *ptr++ = '"'; ptr = cpw(ptr, base + entries[i].pos,
entries[i].keylen); *ptr++ = '"'; *ptr++ = '='; *ptr++ = '>';
-- Gregory Stark EnterpriseDB http://www.enterprisedb.com
