diff options
Diffstat (limited to 'util/uuid.c')
-rw-r--r-- | util/uuid.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/util/uuid.c b/util/uuid.c new file mode 100644 index 0000000000..6815904435 --- /dev/null +++ b/util/uuid.c @@ -0,0 +1,91 @@ +/* + * QEMU UUID functions + * + * Copyright 2016 Red Hat, Inc. + * + * Authors: + * Fam Zheng <famz@redhat.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + * + */ + +#include "qemu/osdep.h" +#include "qemu-common.h" +#include "qemu/uuid.h" +#include "qemu/bswap.h" + +void qemu_uuid_generate(QemuUUID *uuid) +{ + int i; + uint32_t tmp[4]; + + QEMU_BUILD_BUG_ON(sizeof(QemuUUID) != 16); + + for (i = 0; i < 4; ++i) { + tmp[i] = g_random_int(); + } + memcpy(uuid, tmp, sizeof(tmp)); + /* Set the two most significant bits (bits 6 and 7) of the + clock_seq_hi_and_reserved to zero and one, respectively. */ + uuid->data[8] = (uuid->data[8] & 0x3f) | 0x80; + /* Set the four most significant bits (bits 12 through 15) of the + time_hi_and_version field to the 4-bit version number. + */ + uuid->data[6] = (uuid->data[6] & 0xf) | 0x40; +} + +int qemu_uuid_is_null(const QemuUUID *uu) +{ + QemuUUID null_uuid = { 0 }; + return memcmp(uu, &null_uuid, sizeof(QemuUUID)) == 0; +} + +void qemu_uuid_unparse(const QemuUUID *uuid, char *out) +{ + const unsigned char *uu = &uuid->data[0]; + snprintf(out, UUID_FMT_LEN + 1, UUID_FMT, + uu[0], uu[1], uu[2], uu[3], uu[4], uu[5], uu[6], uu[7], + uu[8], uu[9], uu[10], uu[11], uu[12], uu[13], uu[14], uu[15]); +} + +char *qemu_uuid_unparse_strdup(const QemuUUID *uuid) +{ + const unsigned char *uu = &uuid->data[0]; + return g_strdup_printf(UUID_FMT, + uu[0], uu[1], uu[2], uu[3], uu[4], uu[5], uu[6], + uu[7], uu[8], uu[9], uu[10], uu[11], uu[12], + uu[13], uu[14], uu[15]); +} + +int qemu_uuid_parse(const char *str, uint8_t *uuid) +{ + int ret; + + if (strlen(str) != 36) { + return -1; + } + + ret = sscanf(str, UUID_FMT, &uuid[0], &uuid[1], &uuid[2], &uuid[3], + &uuid[4], &uuid[5], &uuid[6], &uuid[7], &uuid[8], &uuid[9], + &uuid[10], &uuid[11], &uuid[12], &uuid[13], &uuid[14], + &uuid[15]); + + if (ret != 16) { + return -1; + } + return 0; +} + +/* Swap from UUID format endian (BE) to the opposite or vice versa. + */ +void qemu_uuid_bswap(QemuUUID *uuid) +{ + assert(QEMU_PTR_IS_ALIGNED(uuid, sizeof(uint32_t))); + bswap32s(&uuid->fields.time_low); + bswap16s(&uuid->fields.time_mid); + bswap16s(&uuid->fields.time_high_and_version); +} |