LXR qemu/include/qemu/osdep.h

   1/*
   2 * OS includes and handling of OS dependencies
   3 *
   4 * This header exists to pull in some common system headers that
   5 * most code in QEMU will want, and to fix up some possible issues with
   6 * it (missing defines, Windows weirdness, and so on).
   7 *
   8 * To avoid getting into possible circular include dependencies, this
   9 * file should not include any other QEMU headers, with the exceptions
  10 * of config-host.h, config-target.h, qemu/compiler.h,
  11 * sysemu/os-posix.h, sysemu/os-win32.h, glib-compat.h and
  12 * qemu/typedefs.h, all of which are doing a similar job to this file
  13 * and are under similar constraints.
  14 *
  15 * This header also contains prototypes for functions defined in
  16 * os-*.c and util/oslib-*.c; those would probably be better split
  17 * out into separate header files.
  18 *
  19 * In an ideal world this header would contain only:
  20 *  (1) things which everybody needs
  21 *  (2) things without which code would work on most platforms but
  22 *      fail to compile or misbehave on a minority of host OSes
  23 *
  24 * This work is licensed under the terms of the GNU GPL, version 2 or later.
  25 * See the COPYING file in the top-level directory.
  26 */
  27#ifndef QEMU_OSDEP_H
  28#define QEMU_OSDEP_H
  29
  30#include "config-host.h"
  31#ifdef NEED_CPU_H
  32#include "config-target.h"
  33#else
  34#include "exec/poison.h"
  35#endif
  36#include "qemu/compiler.h"
  37
  38/* Older versions of C++ don't get definitions of various macros from
  39 * stdlib.h unless we define these macros before first inclusion of
  40 * that system header.
  41 */
  42#ifndef __STDC_CONSTANT_MACROS
  43#define __STDC_CONSTANT_MACROS
  44#endif
  45#ifndef __STDC_LIMIT_MACROS
  46#define __STDC_LIMIT_MACROS
  47#endif
  48#ifndef __STDC_FORMAT_MACROS
  49#define __STDC_FORMAT_MACROS
  50#endif
  51
  52/* The following block of code temporarily renames the daemon() function so the
  53 * compiler does not see the warning associated with it in stdlib.h on OSX
  54 */
  55#ifdef __APPLE__
  56#define daemon qemu_fake_daemon_function
  57#include <stdlib.h>
  58#undef daemon
  59extern int daemon(int, int);
  60#endif
  61
  62#include <stdarg.h>
  63#include <stddef.h>
  64#include <stdbool.h>
  65#include <stdint.h>
  66#include <sys/types.h>
  67#include <stdlib.h>
  68#include <stdio.h>
  69#include <string.h>
  70#include <strings.h>
  71#include <inttypes.h>
  72#include <limits.h>
  73/* Put unistd.h before time.h as that triggers localtime_r/gmtime_r
  74 * function availability on recentish Mingw-w64 platforms. */
  75#include <unistd.h>
  76#include <time.h>
  77#include <ctype.h>
  78#include <errno.h>
  79#include <fcntl.h>
  80#include <sys/stat.h>
  81#include <sys/time.h>
  82#include <assert.h>
  83/* setjmp must be declared before sysemu/os-win32.h
  84 * because it is redefined there. */
  85#include <setjmp.h>
  86#include <signal.h>
  87
  88#ifdef __OpenBSD__
  89#include <sys/signal.h>
  90#endif
  91
  92#ifndef _WIN32
  93#include <sys/wait.h>
  94#else
  95#define WIFEXITED(x)   1
  96#define WEXITSTATUS(x) (x)
  97#endif
  98
  99#ifdef _WIN32
 100#include "sysemu/os-win32.h"
 101#endif
 102
 103#ifdef CONFIG_POSIX
 104#include "sysemu/os-posix.h"
 105#endif
 106
 107#include "glib-compat.h"
 108#include "qemu/typedefs.h"
 109
 110#ifndef O_LARGEFILE
 111#define O_LARGEFILE 0
 112#endif
 113#ifndef O_BINARY
 114#define O_BINARY 0
 115#endif
 116#ifndef MAP_ANONYMOUS
 117#define MAP_ANONYMOUS MAP_ANON
 118#endif
 119#ifndef ENOMEDIUM
 120#define ENOMEDIUM ENODEV
 121#endif
 122#if !defined(ENOTSUP)
 123#define ENOTSUP 4096
 124#endif
 125#if !defined(ECANCELED)
 126#define ECANCELED 4097
 127#endif
 128#if !defined(EMEDIUMTYPE)
 129#define EMEDIUMTYPE 4098
 130#endif
 131#if !defined(ESHUTDOWN)
 132#define ESHUTDOWN 4099
 133#endif
 134#ifndef TIME_MAX
 135#define TIME_MAX LONG_MAX
 136#endif
 137
 138/* HOST_LONG_BITS is the size of a native pointer in bits. */
 139#if UINTPTR_MAX == UINT32_MAX
 140# define HOST_LONG_BITS 32
 141#elif UINTPTR_MAX == UINT64_MAX
 142# define HOST_LONG_BITS 64
 143#else
 144# error Unknown pointer size
 145#endif
 146
 147/* Mac OSX has a <stdint.h> bug that incorrectly defines SIZE_MAX with
 148 * the wrong type. Our replacement isn't usable in preprocessor
 149 * expressions, but it is sufficient for our needs. */
 150#if defined(HAVE_BROKEN_SIZE_MAX) && HAVE_BROKEN_SIZE_MAX
 151#undef SIZE_MAX
 152#define SIZE_MAX ((size_t)-1)
 153#endif
 154
 155#ifndef MIN
 156#define MIN(a, b) (((a) < (b)) ? (a) : (b))
 157#endif
 158#ifndef MAX
 159#define MAX(a, b) (((a) > (b)) ? (a) : (b))
 160#endif
 161
 162/* Minimum function that returns zero only iff both values are zero.
 163 * Intended for use with unsigned values only. */
 164#ifndef MIN_NON_ZERO
 165#define MIN_NON_ZERO(a, b) ((a) == 0 ? (b) : \
 166                                ((b) == 0 ? (a) : (MIN(a, b))))
 167#endif
 168
 169/* Round number down to multiple */
 170#define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m))
 171
 172/* Round number up to multiple. Safe when m is not a power of 2 (see
 173 * ROUND_UP for a faster version when a power of 2 is guaranteed) */
 174#define QEMU_ALIGN_UP(n, m) QEMU_ALIGN_DOWN((n) + (m) - 1, (m))
 175
 176/* Check if n is a multiple of m */
 177#define QEMU_IS_ALIGNED(n, m) (((n) % (m)) == 0)
 178
 179/* n-byte align pointer down */
 180#define QEMU_ALIGN_PTR_DOWN(p, n) \
 181    ((typeof(p))QEMU_ALIGN_DOWN((uintptr_t)(p), (n)))
 182
 183/* n-byte align pointer up */
 184#define QEMU_ALIGN_PTR_UP(p, n) \
 185    ((typeof(p))QEMU_ALIGN_UP((uintptr_t)(p), (n)))
 186
 187/* Check if pointer p is n-bytes aligned */
 188#define QEMU_PTR_IS_ALIGNED(p, n) QEMU_IS_ALIGNED((uintptr_t)(p), (n))
 189
 190/* Round number up to multiple. Requires that d be a power of 2 (see
 191 * QEMU_ALIGN_UP for a safer but slower version on arbitrary
 192 * numbers) */
 193#ifndef ROUND_UP
 194#define ROUND_UP(n,d) (((n) + (d) - 1) & -(d))
 195#endif
 196
 197#ifndef DIV_ROUND_UP
 198#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
 199#endif
 200
 201#ifndef ARRAY_SIZE
 202#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
 203#endif
 204
 205int qemu_daemon(int nochdir, int noclose);
 206void *qemu_try_memalign(size_t alignment, size_t size);
 207void *qemu_memalign(size_t alignment, size_t size);
 208void *qemu_anon_ram_alloc(size_t size, uint64_t *align);
 209void qemu_vfree(void *ptr);
 210void qemu_anon_ram_free(void *ptr, size_t size);
 211
 212#define QEMU_MADV_INVALID -1
 213
 214#if defined(CONFIG_MADVISE)
 215
 216#define QEMU_MADV_WILLNEED  MADV_WILLNEED
 217#define QEMU_MADV_DONTNEED  MADV_DONTNEED
 218#ifdef MADV_DONTFORK
 219#define QEMU_MADV_DONTFORK  MADV_DONTFORK
 220#else
 221#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
 222#endif
 223#ifdef MADV_MERGEABLE
 224#define QEMU_MADV_MERGEABLE MADV_MERGEABLE
 225#else
 226#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
 227#endif
 228#ifdef MADV_UNMERGEABLE
 229#define QEMU_MADV_UNMERGEABLE MADV_UNMERGEABLE
 230#else
 231#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
 232#endif
 233#ifdef MADV_DODUMP
 234#define QEMU_MADV_DODUMP MADV_DODUMP
 235#else
 236#define QEMU_MADV_DODUMP QEMU_MADV_INVALID
 237#endif
 238#ifdef MADV_DONTDUMP
 239#define QEMU_MADV_DONTDUMP MADV_DONTDUMP
 240#else
 241#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
 242#endif
 243#ifdef MADV_HUGEPAGE
 244#define QEMU_MADV_HUGEPAGE MADV_HUGEPAGE
 245#else
 246#define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID
 247#endif
 248#ifdef MADV_NOHUGEPAGE
 249#define QEMU_MADV_NOHUGEPAGE MADV_NOHUGEPAGE
 250#else
 251#define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID
 252#endif
 253
 254#elif defined(CONFIG_POSIX_MADVISE)
 255
 256#define QEMU_MADV_WILLNEED  POSIX_MADV_WILLNEED
 257#define QEMU_MADV_DONTNEED  POSIX_MADV_DONTNEED
 258#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
 259#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
 260#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
 261#define QEMU_MADV_DODUMP QEMU_MADV_INVALID
 262#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
 263#define QEMU_MADV_HUGEPAGE  QEMU_MADV_INVALID
 264#define QEMU_MADV_NOHUGEPAGE  QEMU_MADV_INVALID
 265
 266#else /* no-op */
 267
 268#define QEMU_MADV_WILLNEED  QEMU_MADV_INVALID
 269#define QEMU_MADV_DONTNEED  QEMU_MADV_INVALID
 270#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
 271#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
 272#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
 273#define QEMU_MADV_DODUMP QEMU_MADV_INVALID
 274#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
 275#define QEMU_MADV_HUGEPAGE  QEMU_MADV_INVALID
 276#define QEMU_MADV_NOHUGEPAGE  QEMU_MADV_INVALID
 277
 278#endif
 279
 280#if defined(__linux__) && \
 281    (defined(__x86_64__) || defined(__arm__) || defined(__aarch64__))
 282   /* Use 2 MiB alignment so transparent hugepages can be used by KVM.
 283      Valgrind does not support alignments larger than 1 MiB,
 284      therefore we need special code which handles running on Valgrind. */
 285#  define QEMU_VMALLOC_ALIGN (512 * 4096)
 286#elif defined(__linux__) && defined(__s390x__)
 287   /* Use 1 MiB (segment size) alignment so gmap can be used by KVM. */
 288#  define QEMU_VMALLOC_ALIGN (256 * 4096)
 289#else
 290#  define QEMU_VMALLOC_ALIGN getpagesize()
 291#endif
 292
 293int qemu_madvise(void *addr, size_t len, int advice);
 294
 295int qemu_open(const char *name, int flags, ...);
 296int qemu_close(int fd);
 297#ifndef _WIN32
 298int qemu_dup(int fd);
 299#endif
 300
 301#if defined(__HAIKU__) && defined(__i386__)
 302#define FMT_pid "%ld"
 303#elif defined(WIN64)
 304#define FMT_pid "%" PRId64
 305#else
 306#define FMT_pid "%d"
 307#endif
 308
 309int qemu_create_pidfile(const char *filename);
 310int qemu_get_thread_id(void);
 311
 312#ifndef CONFIG_IOVEC
 313struct iovec {
 314    void *iov_base;
 315    size_t iov_len;
 316};
 317/*
 318 * Use the same value as Linux for now.
 319 */
 320#define IOV_MAX 1024
 321
 322ssize_t readv(int fd, const struct iovec *iov, int iov_cnt);
 323ssize_t writev(int fd, const struct iovec *iov, int iov_cnt);
 324#else
 325#include <sys/uio.h>
 326#endif
 327
 328#ifdef _WIN32
 329static inline void qemu_timersub(const struct timeval *val1,
 330                                 const struct timeval *val2,
 331                                 struct timeval *res)
 332{
 333    res->tv_sec = val1->tv_sec - val2->tv_sec;
 334    if (val1->tv_usec < val2->tv_usec) {
 335        res->tv_sec--;
 336        res->tv_usec = val1->tv_usec - val2->tv_usec + 1000 * 1000;
 337    } else {
 338        res->tv_usec = val1->tv_usec - val2->tv_usec;
 339    }
 340}
 341#else
 342#define qemu_timersub timersub
 343#endif
 344
 345void qemu_set_cloexec(int fd);
 346
 347/* Starting on QEMU 2.5, qemu_hw_version() returns "2.5+" by default
 348 * instead of QEMU_VERSION, so setting hw_version on MachineClass
 349 * is no longer mandatory.
 350 *
 351 * Do NOT change this string, or it will break compatibility on all
 352 * machine classes that don't set hw_version.
 353 */
 354#define QEMU_HW_VERSION "2.5+"
 355
 356/* QEMU "hardware version" setting. Used to replace code that exposed
 357 * QEMU_VERSION to guests in the past and need to keep compatibility.
 358 * Do not use qemu_hw_version() in new code.
 359 */
 360void qemu_set_hw_version(const char *);
 361const char *qemu_hw_version(void);
 362
 363void fips_set_state(bool requested);
 364bool fips_get_state(void);
 365
 366/* Return a dynamically allocated pathname denoting a file or directory that is
 367 * appropriate for storing local state.
 368 *
 369 * @relative_pathname need not start with a directory separator; one will be
 370 * added automatically.
 371 *
 372 * The caller is responsible for releasing the value returned with g_free()
 373 * after use.
 374 */
 375char *qemu_get_local_state_pathname(const char *relative_pathname);
 376
 377/* Find program directory, and save it for later usage with
 378 * qemu_get_exec_dir().
 379 * Try OS specific API first, if not working, parse from argv0. */
 380void qemu_init_exec_dir(const char *argv0);
 381
 382/* Get the saved exec dir.
 383 * Caller needs to release the returned string by g_free() */
 384char *qemu_get_exec_dir(void);
 385
 386/**
 387 * qemu_getauxval:
 388 * @type: the auxiliary vector key to lookup
 389 *
 390 * Search the auxiliary vector for @type, returning the value
 391 * or 0 if @type is not present.
 392 */
 393unsigned long qemu_getauxval(unsigned long type);
 394
 395void qemu_set_tty_echo(int fd, bool echo);
 396
 397void os_mem_prealloc(int fd, char *area, size_t sz, Error **errp);
 398
 399int qemu_read_password(char *buf, int buf_size);
 400
 401/**
 402 * qemu_get_pid_name:
 403 * @pid: pid of a process
 404 *
 405 * For given @pid fetch its name. Caller is responsible for
 406 * freeing the string when no longer needed.
 407 * Returns allocated string on success, NULL on failure.
 408 */
 409char *qemu_get_pid_name(pid_t pid);
 410
 411/**
 412 * qemu_fork:
 413 *
 414 * A version of fork that avoids signal handler race
 415 * conditions that can lead to child process getting
 416 * signals that are otherwise only expected by the
 417 * parent. It also resets all signal handlers to the
 418 * default settings.
 419 *
 420 * Returns 0 to child process, pid number to parent
 421 * or -1 on failure.
 422 */
 423pid_t qemu_fork(Error **errp);
 424
 425#endif
 426