/* * Dealing with identifiers * * Copyright (C) 2014 Red Hat, Inc. * * Authors: * Markus Armbruster <armbru@redhat.com>, * * This work is licensed under the terms of the GNU LGPL, version 2.1 * or later. See the COPYING.LIB file in the top-level directory. */ #include "qemu/osdep.h" #include "qemu-common.h" #include "qemu/id.h" bool id_wellformed(const char *id) { int i; if (!qemu_isalpha(id[0])) { return false; } for (i = 1; id[i]; i++) { if (!qemu_isalnum(id[i]) && !strchr("-._", id[i])) { return false; } } return true; } #define ID_SPECIAL_CHAR '#' static const char *const id_subsys_str[ID_MAX] = { [ID_QDEV] = "qdev", [ID_BLOCK] = "block", }; /* * Generates an ID of the form PREFIX SUBSYSTEM NUMBER * where: * * - PREFIX is the reserved character '#' * - SUBSYSTEM identifies the subsystem creating the ID * - NUMBER is a decimal number unique within SUBSYSTEM. * * Example: "#block146" * * Note that these IDs do not satisfy id_wellformed(). * * The caller is responsible for freeing the returned string with g_free() */ char *id_generate(IdSubSystems id) { static uint64_t id_counters[ID_MAX]; uint32_t rnd; assert(id < ARRAY_SIZE(id_subsys_str)); assert(id_subsys_str[id]); rnd = g_random_int_range(0, 100); return g_strdup_printf("%c%s%" PRIu64 "%02" PRId32, ID_SPECIAL_CHAR, id_subsys_str[id], id_counters[id]++, rnd); }