/*
* downcase_truncate_identifier() --- do appropriate downcasing and
* truncation of an unquoted identifier. Optionally warn of truncation.
*
* Returns a palloc'd string containing the adjusted identifier.
*
* Note: in some usages the passed string is not null-terminated.
*
* Note: the API of this function is designed to allow for downcasing
* transformations that increase the string length, but we don't yet
* support that. If you want to implement it, you'll need to fix
* SplitIdentifierString() in utils/adt/varlena.c.
*/
char *
downcase_truncate_identifier(const char *ident, int len, bool warn)
{
char *result;
int i;
result = palloc(len + 1);
/*
* SQL99 specifies Unicode-aware case normalization, which we don't yet
* have the infrastructure for. Instead we use tolower() to provide a
* locale-aware translation. However, there are some locales where this
* is not right either (eg, Turkish may do strange things with 'i' and
* 'I'). Our current compromise is to use tolower() for characters with
* the high bit set, and use an ASCII-only downcasing for 7-bit
* characters.
*/
for (i = 0; i < len; i++)
{
unsigned char ch = (unsigned char) ident[i];
if (ch >= 'A' && ch <= 'Z')
ch += 'a' - 'A';
else if (IS_HIGHBIT_SET(ch) && isupper(ch))
ch = tolower(ch);
result[i] = (char) ch;
}
result[i] = '\0';
if (i >= NAMEDATALEN)
truncate_identifier(result, i, warn);
return result;
}
/*
* makeArrayTypeName
* - given a base type name, make an array type name for it
*
* the caller is responsible for pfreeing the result
*/
char *
makeArrayTypeName(const char *typeName, Oid typeNamespace)
{
char *arr = (char *) palloc(NAMEDATALEN);
int namelen = strlen(typeName);
Relation pg_type_desc;
int i;
/*
* The idea is to prepend underscores as needed until we make a name that
* doesn't collide with anything...
*/
pg_type_desc = heap_open(TypeRelationId, AccessShareLock);
for (i = 1; i < NAMEDATALEN - 1; i++)
{
arr[i - 1] = '_';
if (i + namelen < NAMEDATALEN)
strcpy(arr + i, typeName);
else
{
memcpy(arr + i, typeName, NAMEDATALEN - i);
truncate_identifier(arr, NAMEDATALEN, false);
}
if (!SearchSysCacheExists(TYPENAMENSP,
CStringGetDatum(arr),
ObjectIdGetDatum(typeNamespace),
0, 0))
break;
}
heap_close(pg_type_desc, AccessShareLock);
if (i >= NAMEDATALEN - 1)
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("could not form array type name for type \"%s\"",
typeName)));
return arr;
}
