uuid-ossp.c

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/*-------------------------------------------------------------------------
 *
 * UUID generation functions using the OSSP UUID library
 *
 * Copyright (c) 2007-2013, PostgreSQL Global Development Group
 *
 * contrib/uuid-ossp/uuid-ossp.c
 *
 *-------------------------------------------------------------------------
 */

#include "postgres.h"
#include "fmgr.h"
#include "utils/builtins.h"
#include "utils/uuid.h"

/*
 * There's some confusion over the location of the uuid.h header file.
 * On Debian, it's installed as ossp/uuid.h, while on Fedora, or if you
 * install ossp-uuid from a tarball, it's installed as uuid.h. Don't know
 * what other systems do.
 */
#ifdef HAVE_OSSP_UUID_H
#include <ossp/uuid.h>
#else
#ifdef HAVE_UUID_H
#include <uuid.h>
#else
#error OSSP uuid.h not found
#endif
#endif

/* better both be 16 */
#if (UUID_LEN != UUID_LEN_BIN)
#error UUID length mismatch
#endif


PG_MODULE_MAGIC;


Datum       uuid_nil(PG_FUNCTION_ARGS);
Datum       uuid_ns_dns(PG_FUNCTION_ARGS);
Datum       uuid_ns_url(PG_FUNCTION_ARGS);
Datum       uuid_ns_oid(PG_FUNCTION_ARGS);
Datum       uuid_ns_x500(PG_FUNCTION_ARGS);

Datum       uuid_generate_v1(PG_FUNCTION_ARGS);
Datum       uuid_generate_v1mc(PG_FUNCTION_ARGS);
Datum       uuid_generate_v3(PG_FUNCTION_ARGS);
Datum       uuid_generate_v4(PG_FUNCTION_ARGS);
Datum       uuid_generate_v5(PG_FUNCTION_ARGS);


PG_FUNCTION_INFO_V1(uuid_nil);
PG_FUNCTION_INFO_V1(uuid_ns_dns);
PG_FUNCTION_INFO_V1(uuid_ns_url);
PG_FUNCTION_INFO_V1(uuid_ns_oid);
PG_FUNCTION_INFO_V1(uuid_ns_x500);

PG_FUNCTION_INFO_V1(uuid_generate_v1);
PG_FUNCTION_INFO_V1(uuid_generate_v1mc);
PG_FUNCTION_INFO_V1(uuid_generate_v3);
PG_FUNCTION_INFO_V1(uuid_generate_v4);
PG_FUNCTION_INFO_V1(uuid_generate_v5);

static void
pguuid_complain(uuid_rc_t rc)
{
    char       *err = uuid_error(rc);

    if (err != NULL)
        ereport(ERROR,
                (errcode(ERRCODE_EXTERNAL_ROUTINE_EXCEPTION),
                 errmsg("OSSP uuid library failure: %s", err)));
    else
        ereport(ERROR,
                (errcode(ERRCODE_EXTERNAL_ROUTINE_EXCEPTION),
                 errmsg("OSSP uuid library failure: error code %d", rc)));
}

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 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
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));
}


Datum
uuid_nil(PG_FUNCTION_ARGS)
{
    return special_uuid_value("nil");
}


Datum
uuid_ns_dns(PG_FUNCTION_ARGS)
{
    return special_uuid_value("ns:DNS");
}


Datum
uuid_ns_url(PG_FUNCTION_ARGS)
{
    return special_uuid_value("ns:URL");
}


Datum
uuid_ns_oid(PG_FUNCTION_ARGS)
{
    return special_uuid_value("ns:OID");
}


Datum
uuid_ns_x500(PG_FUNCTION_ARGS)
{
    return special_uuid_value("ns:X500");
}


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));
}


Datum
uuid_generate_v1(PG_FUNCTION_ARGS)
{
    return uuid_generate_internal(UUID_MAKE_V1, NULL, NULL);
}


Datum
uuid_generate_v1mc(PG_FUNCTION_ARGS)
{
    return uuid_generate_internal(UUID_MAKE_V1 | UUID_MAKE_MC, NULL, NULL);
}


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;
}


Datum
uuid_generate_v3(PG_FUNCTION_ARGS)
{
    pg_uuid_t  *ns = PG_GETARG_UUID_P(0);
    text       *name = PG_GETARG_TEXT_P(1);

    return uuid_generate_v35_internal(UUID_MAKE_V3, ns, name);
}


Datum
uuid_generate_v4(PG_FUNCTION_ARGS)
{
    return uuid_generate_internal(UUID_MAKE_V4, NULL, NULL);
}


Datum
uuid_generate_v5(PG_FUNCTION_ARGS)
{
    pg_uuid_t  *ns = PG_GETARG_UUID_P(0);
    text       *name = PG_GETARG_TEXT_P(1);

    return uuid_generate_v35_internal(UUID_MAKE_V5, ns, name);
}