static void
string_to_uuid(const char *str, uuid_t *uuid)
{
uuid_rc_t rc;
rc = uuid_import(uuid, UUID_FMT_STR, str, UUID_LEN_STR + 1);
if (rc != UUID_RC_OK)
pguuid_complain(rc);
}
static Datum
uuid_generate_internal(int mode, const uuid_t *ns, const char *name)
{
uuid_t *uuid;
char *str;
uuid_rc_t rc;
rc = uuid_create(&uuid);
if (rc != UUID_RC_OK)
pguuid_complain(rc);
rc = uuid_make(uuid, mode, ns, name);
if (rc != UUID_RC_OK)
pguuid_complain(rc);
str = uuid_to_string(uuid);
rc = uuid_destroy(uuid);
if (rc != UUID_RC_OK)
pguuid_complain(rc);
return DirectFunctionCall1(uuid_in, CStringGetDatum(str));
}
static Datum
special_uuid_value(const char *name)
{
uuid_t *uuid;
char *str;
uuid_rc_t rc;
rc = uuid_create(&uuid);
if (rc != UUID_RC_OK)
pguuid_complain(rc);
rc = uuid_load(uuid, name);
if (rc != UUID_RC_OK)
pguuid_complain(rc);
str = uuid_to_string(uuid);
rc = uuid_destroy(uuid);
if (rc != UUID_RC_OK)
pguuid_complain(rc);
return DirectFunctionCall1(uuid_in, CStringGetDatum(str));
}
static char *
uuid_to_string(const uuid_t *uuid)
{
char *buf = palloc(UUID_LEN_STR + 1);
void *ptr = buf;
size_t len = UUID_LEN_STR + 1;
uuid_rc_t rc;
rc = uuid_export(uuid, UUID_FMT_STR, &ptr, &len);
if (rc != UUID_RC_OK)
pguuid_complain(rc);
return buf;
}
static Datum
uuid_generate_v35_internal(int mode, pg_uuid_t *ns, text *name)
{
uuid_t *ns_uuid;
Datum result;
uuid_rc_t rc;
rc = uuid_create(&ns_uuid);
if (rc != UUID_RC_OK)
pguuid_complain(rc);
string_to_uuid(DatumGetCString(DirectFunctionCall1(uuid_out, UUIDPGetDatum(ns))),
ns_uuid);
result = uuid_generate_internal(mode,
ns_uuid,
text_to_cstring(name));
rc = uuid_destroy(ns_uuid);
if (rc != UUID_RC_OK)
pguuid_complain(rc);
return result;
}
/*
* We create a uuid_t object just once per session and re-use it for all
* operations in this module. OSSP UUID caches the system MAC address and
* other state in this object. Reusing the object has a number of benefits:
* saving the cycles needed to fetch the system MAC address over and over,
* reducing the amount of entropy we draw from /dev/urandom, and providing a
* positive guarantee that successive generated V1-style UUIDs don't collide.
* (On a machine fast enough to generate multiple UUIDs per microsecond,
* or whatever the system's wall-clock resolution is, we'd otherwise risk
* collisions whenever random initialization of the uuid_t's clock sequence
* value chanced to produce duplicates.)
*
* However: when we're doing V3 or V5 UUID creation, uuid_make needs two
* uuid_t objects, one holding the namespace UUID and one for the result.
* It's unspecified whether it's safe to use the same uuid_t for both cases,
* so let's cache a second uuid_t for use as the namespace holder object.
*/
static uuid_t *
get_cached_uuid_t(int which)
{
static uuid_t *cached_uuid[2] = {NULL, NULL};
if (cached_uuid[which] == NULL)
{
uuid_rc_t rc;
rc = uuid_create(&cached_uuid[which]);
if (rc != UUID_RC_OK)
{
cached_uuid[which] = NULL;
pguuid_complain(rc);
}
}
return cached_uuid[which];
}
