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-rw-r--r--util/uuid.c114
1 files changed, 114 insertions, 0 deletions
diff --git a/util/uuid.c b/util/uuid.c
new file mode 100644
index 0000000000..dd6b5fdf05
--- /dev/null
+++ b/util/uuid.c
@@ -0,0 +1,114 @@
+/*
+ *  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)
+{
+    static QemuUUID null_uuid;
+    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]);
+}
+
+static bool qemu_uuid_is_valid(const char *str)
+{
+    int i;
+
+    for (i = 0; i < strlen(str); i++) {
+        const char c = str[i];
+        if (i == 8 || i == 13 || i == 18 || i == 23) {
+            if (str[i] != '-') {
+                return false;
+            }
+        } else {
+            if ((c >= '0' && c <= '9') ||
+                (c >= 'A' && c <= 'F') ||
+                (c >= 'a' && c <= 'f')) {
+                continue;
+            }
+            return false;
+        }
+    }
+    return i == 36;
+}
+
+int qemu_uuid_parse(const char *str, QemuUUID *uuid)
+{
+    unsigned char *uu = &uuid->data[0];
+    int ret;
+
+    if (!qemu_uuid_is_valid(str)) {
+        return -1;
+    }
+
+    ret = sscanf(str, 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]);
+
+    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);
+}