osdep.h (24212B)
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 33#else 34#include "exec/poison.h" 35#endif 36 37#include "qemu/compiler.h" 38 39/* Older versions of C++ don't get definitions of various macros from 40 * stdlib.h unless we define these macros before first inclusion of 41 * that system header. 42 */ 43#ifndef __STDC_CONSTANT_MACROS 44#define __STDC_CONSTANT_MACROS 45#endif 46#ifndef __STDC_LIMIT_MACROS 47#define __STDC_LIMIT_MACROS 48#endif 49#ifndef __STDC_FORMAT_MACROS 50#define __STDC_FORMAT_MACROS 51#endif 52 53/* The following block of code temporarily renames the daemon() function so the 54 * compiler does not see the warning associated with it in stdlib.h on OSX 55 */ 56#ifdef __APPLE__ 57#define daemon qemu_fake_daemon_function 58#include <stdlib.h> 59#undef daemon 60QEMU_EXTERN_C int daemon(int, int); 61#endif 62 63#ifdef _WIN32 64/* as defined in sdkddkver.h */ 65#ifndef _WIN32_WINNT 66#define _WIN32_WINNT 0x0600 /* Vista */ 67#endif 68/* reduces the number of implicitly included headers */ 69#ifndef WIN32_LEAN_AND_MEAN 70#define WIN32_LEAN_AND_MEAN 71#endif 72#endif 73 74/* enable C99/POSIX format strings (needs mingw32-runtime 3.15 or later) */ 75#ifdef __MINGW32__ 76#define __USE_MINGW_ANSI_STDIO 1 77#endif 78 79#include <stdarg.h> 80#include <stddef.h> 81#include <stdbool.h> 82#include <stdint.h> 83#include <sys/types.h> 84#include <stdlib.h> 85#include <stdio.h> 86 87#include <string.h> 88#include <strings.h> 89#include <inttypes.h> 90#include <limits.h> 91/* Put unistd.h before time.h as that triggers localtime_r/gmtime_r 92 * function availability on recentish Mingw-w64 platforms. */ 93#include <unistd.h> 94#include <time.h> 95#include <ctype.h> 96#include <errno.h> 97#include <fcntl.h> 98#include <getopt.h> 99#include <sys/stat.h> 100#include <sys/time.h> 101#include <assert.h> 102/* setjmp must be declared before sysemu/os-win32.h 103 * because it is redefined there. */ 104#include <setjmp.h> 105#include <signal.h> 106 107#ifdef CONFIG_IOVEC 108#include <sys/uio.h> 109#endif 110 111#if defined(__linux__) && defined(__sparc__) 112/* The SPARC definition of QEMU_VMALLOC_ALIGN needs SHMLBA */ 113#include <sys/shm.h> 114#endif 115 116#ifndef _WIN32 117#include <sys/wait.h> 118#else 119#define WIFEXITED(x) 1 120#define WEXITSTATUS(x) (x) 121#endif 122 123#ifdef __APPLE__ 124#include <AvailabilityMacros.h> 125#endif 126 127/* 128 * This is somewhat like a system header; it must be outside any extern "C" 129 * block because it includes system headers itself, including glib.h, 130 * which will not compile if inside an extern "C" block. 131 */ 132#include "glib-compat.h" 133 134#ifdef _WIN32 135#include "sysemu/os-win32.h" 136#endif 137 138#ifdef CONFIG_POSIX 139#include "sysemu/os-posix.h" 140#endif 141 142#ifdef __cplusplus 143extern "C" { 144#endif 145 146#include "qemu/typedefs.h" 147 148/* 149 * For mingw, as of v6.0.0, the function implementing the assert macro is 150 * not marked as noreturn, so the compiler cannot delete code following an 151 * assert(false) as unused. We rely on this within the code base to delete 152 * code that is unreachable when features are disabled. 153 * All supported versions of Glib's g_assert() satisfy this requirement. 154 */ 155#ifdef __MINGW32__ 156#undef assert 157#define assert(x) g_assert(x) 158#endif 159 160/* 161 * According to waitpid man page: 162 * WCOREDUMP 163 * This macro is not specified in POSIX.1-2001 and is not 164 * available on some UNIX implementations (e.g., AIX, SunOS). 165 * Therefore, enclose its use inside #ifdef WCOREDUMP ... #endif. 166 */ 167#ifndef WCOREDUMP 168#define WCOREDUMP(status) 0 169#endif 170/* 171 * We have a lot of unaudited code that may fail in strange ways, or 172 * even be a security risk during migration, if you disable assertions 173 * at compile-time. You may comment out these safety checks if you 174 * absolutely want to disable assertion overhead, but it is not 175 * supported upstream so the risk is all yours. Meanwhile, please 176 * submit patches to remove any side-effects inside an assertion, or 177 * fixing error handling that should use Error instead of assert. 178 */ 179#ifdef NDEBUG 180#error building with NDEBUG is not supported 181#endif 182#ifdef G_DISABLE_ASSERT 183#error building with G_DISABLE_ASSERT is not supported 184#endif 185 186#ifndef O_LARGEFILE 187#define O_LARGEFILE 0 188#endif 189#ifndef O_BINARY 190#define O_BINARY 0 191#endif 192#ifndef MAP_ANONYMOUS 193#define MAP_ANONYMOUS MAP_ANON 194#endif 195#ifndef MAP_FIXED_NOREPLACE 196#define MAP_FIXED_NOREPLACE 0 197#endif 198#ifndef MAP_NORESERVE 199#define MAP_NORESERVE 0 200#endif 201#ifndef ENOMEDIUM 202#define ENOMEDIUM ENODEV 203#endif 204#if !defined(ENOTSUP) 205#define ENOTSUP 4096 206#endif 207#if !defined(ECANCELED) 208#define ECANCELED 4097 209#endif 210#if !defined(EMEDIUMTYPE) 211#define EMEDIUMTYPE 4098 212#endif 213#if !defined(ESHUTDOWN) 214#define ESHUTDOWN 4099 215#endif 216 217/* time_t may be either 32 or 64 bits depending on the host OS, and 218 * can be either signed or unsigned, so we can't just hardcode a 219 * specific maximum value. This is not a C preprocessor constant, 220 * so you can't use TIME_MAX in an #ifdef, but for our purposes 221 * this isn't a problem. 222 */ 223 224/* The macros TYPE_SIGNED, TYPE_WIDTH, and TYPE_MAXIMUM are from 225 * Gnulib, and are under the LGPL v2.1 or (at your option) any 226 * later version. 227 */ 228 229/* True if the real type T is signed. */ 230#define TYPE_SIGNED(t) (!((t)0 < (t)-1)) 231 232/* The width in bits of the integer type or expression T. 233 * Padding bits are not supported. 234 */ 235#define TYPE_WIDTH(t) (sizeof(t) * CHAR_BIT) 236 237/* The maximum and minimum values for the integer type T. */ 238#define TYPE_MAXIMUM(t) \ 239 ((t) (!TYPE_SIGNED(t) \ 240 ? (t)-1 \ 241 : ((((t)1 << (TYPE_WIDTH(t) - 2)) - 1) * 2 + 1))) 242 243#ifndef TIME_MAX 244#define TIME_MAX TYPE_MAXIMUM(time_t) 245#endif 246 247/* HOST_LONG_BITS is the size of a native pointer in bits. */ 248#if UINTPTR_MAX == UINT32_MAX 249# define HOST_LONG_BITS 32 250#elif UINTPTR_MAX == UINT64_MAX 251# define HOST_LONG_BITS 64 252#else 253# error Unknown pointer size 254#endif 255 256/* Mac OSX has a <stdint.h> bug that incorrectly defines SIZE_MAX with 257 * the wrong type. Our replacement isn't usable in preprocessor 258 * expressions, but it is sufficient for our needs. */ 259#ifdef HAVE_BROKEN_SIZE_MAX 260#undef SIZE_MAX 261#define SIZE_MAX ((size_t)-1) 262#endif 263 264/* 265 * Two variations of MIN/MAX macros. The first is for runtime use, and 266 * evaluates arguments only once (so it is safe even with side 267 * effects), but will not work in constant contexts (such as array 268 * size declarations) because of the '{}'. The second is for constant 269 * expression use, where evaluating arguments twice is safe because 270 * the result is going to be constant anyway, but will not work in a 271 * runtime context because of a void expression where a value is 272 * expected. Thus, both gcc and clang will fail to compile if you use 273 * the wrong macro (even if the error may seem a bit cryptic). 274 * 275 * Note that neither form is usable as an #if condition; if you truly 276 * need to write conditional code that depends on a minimum or maximum 277 * determined by the pre-processor instead of the compiler, you'll 278 * have to open-code it. Sadly, Coverity is severely confused by the 279 * constant variants, so we have to dumb things down there. 280 */ 281#undef MIN 282#define MIN(a, b) \ 283 ({ \ 284 typeof(1 ? (a) : (b)) _a = (a), _b = (b); \ 285 _a < _b ? _a : _b; \ 286 }) 287#undef MAX 288#define MAX(a, b) \ 289 ({ \ 290 typeof(1 ? (a) : (b)) _a = (a), _b = (b); \ 291 _a > _b ? _a : _b; \ 292 }) 293 294#ifdef __COVERITY__ 295# define MIN_CONST(a, b) ((a) < (b) ? (a) : (b)) 296# define MAX_CONST(a, b) ((a) > (b) ? (a) : (b)) 297#else 298# define MIN_CONST(a, b) \ 299 __builtin_choose_expr( \ 300 __builtin_constant_p(a) && __builtin_constant_p(b), \ 301 (a) < (b) ? (a) : (b), \ 302 ((void)0)) 303# define MAX_CONST(a, b) \ 304 __builtin_choose_expr( \ 305 __builtin_constant_p(a) && __builtin_constant_p(b), \ 306 (a) > (b) ? (a) : (b), \ 307 ((void)0)) 308#endif 309 310/* 311 * Minimum function that returns zero only if both values are zero. 312 * Intended for use with unsigned values only. 313 */ 314#ifndef MIN_NON_ZERO 315#define MIN_NON_ZERO(a, b) \ 316 ({ \ 317 typeof(1 ? (a) : (b)) _a = (a), _b = (b); \ 318 _a == 0 ? _b : (_b == 0 || _b > _a) ? _a : _b; \ 319 }) 320#endif 321 322/* 323 * Round number down to multiple. Safe when m is not a power of 2 (see 324 * ROUND_DOWN for a faster version when a power of 2 is guaranteed). 325 */ 326#define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m)) 327 328/* 329 * Round number up to multiple. Safe when m is not a power of 2 (see 330 * ROUND_UP for a faster version when a power of 2 is guaranteed). 331 */ 332#define QEMU_ALIGN_UP(n, m) QEMU_ALIGN_DOWN((n) + (m) - 1, (m)) 333 334/* Check if n is a multiple of m */ 335#define QEMU_IS_ALIGNED(n, m) (((n) % (m)) == 0) 336 337/* n-byte align pointer down */ 338#define QEMU_ALIGN_PTR_DOWN(p, n) \ 339 ((typeof(p))QEMU_ALIGN_DOWN((uintptr_t)(p), (n))) 340 341/* n-byte align pointer up */ 342#define QEMU_ALIGN_PTR_UP(p, n) \ 343 ((typeof(p))QEMU_ALIGN_UP((uintptr_t)(p), (n))) 344 345/* Check if pointer p is n-bytes aligned */ 346#define QEMU_PTR_IS_ALIGNED(p, n) QEMU_IS_ALIGNED((uintptr_t)(p), (n)) 347 348/* 349 * Round number down to multiple. Requires that d be a power of 2 (see 350 * QEMU_ALIGN_UP for a safer but slower version on arbitrary 351 * numbers); works even if d is a smaller type than n. 352 */ 353#ifndef ROUND_DOWN 354#define ROUND_DOWN(n, d) ((n) & -(0 ? (n) : (d))) 355#endif 356 357/* 358 * Round number up to multiple. Requires that d be a power of 2 (see 359 * QEMU_ALIGN_UP for a safer but slower version on arbitrary 360 * numbers); works even if d is a smaller type than n. 361 */ 362#ifndef ROUND_UP 363#define ROUND_UP(n, d) ROUND_DOWN((n) + (d) - 1, (d)) 364#endif 365 366#ifndef DIV_ROUND_UP 367#define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d)) 368#endif 369 370/* 371 * &(x)[0] is always a pointer - if it's same type as x then the argument is a 372 * pointer, not an array. 373 */ 374#define QEMU_IS_ARRAY(x) (!__builtin_types_compatible_p(typeof(x), \ 375 typeof(&(x)[0]))) 376#ifndef ARRAY_SIZE 377#define ARRAY_SIZE(x) ((sizeof(x) / sizeof((x)[0])) + \ 378 QEMU_BUILD_BUG_ON_ZERO(!QEMU_IS_ARRAY(x))) 379#endif 380 381int qemu_daemon(int nochdir, int noclose); 382void *qemu_try_memalign(size_t alignment, size_t size); 383void *qemu_memalign(size_t alignment, size_t size); 384void *qemu_anon_ram_alloc(size_t size, uint64_t *align, bool shared, 385 bool noreserve); 386void qemu_vfree(void *ptr); 387void qemu_anon_ram_free(void *ptr, size_t size); 388 389/* 390 * It's an analog of GLIB's g_autoptr_cleanup_generic_gfree(), used to define 391 * g_autofree macro. 392 */ 393static inline void qemu_cleanup_generic_vfree(void *p) 394{ 395 void **pp = (void **)p; 396 qemu_vfree(*pp); 397} 398 399/* 400 * Analog of g_autofree, but qemu_vfree is called on cleanup instead of g_free. 401 */ 402#define QEMU_AUTO_VFREE __attribute__((cleanup(qemu_cleanup_generic_vfree))) 403 404/* 405 * Abstraction of PROT_ and MAP_ flags as passed to mmap(), for example, 406 * consumed by qemu_ram_mmap(). 407 */ 408 409/* Map PROT_READ instead of PROT_READ | PROT_WRITE. */ 410#define QEMU_MAP_READONLY (1 << 0) 411 412/* Use MAP_SHARED instead of MAP_PRIVATE. */ 413#define QEMU_MAP_SHARED (1 << 1) 414 415/* 416 * Use MAP_SYNC | MAP_SHARED_VALIDATE if supported. Ignored without 417 * QEMU_MAP_SHARED. If mapping fails, warn and fallback to !QEMU_MAP_SYNC. 418 */ 419#define QEMU_MAP_SYNC (1 << 2) 420 421/* 422 * Use MAP_NORESERVE to skip reservation of swap space (or huge pages if 423 * applicable). Bail out if not supported/effective. 424 */ 425#define QEMU_MAP_NORESERVE (1 << 3) 426 427 428#define QEMU_MADV_INVALID -1 429 430#if defined(CONFIG_MADVISE) 431 432#define QEMU_MADV_WILLNEED MADV_WILLNEED 433#define QEMU_MADV_DONTNEED MADV_DONTNEED 434#ifdef MADV_DONTFORK 435#define QEMU_MADV_DONTFORK MADV_DONTFORK 436#else 437#define QEMU_MADV_DONTFORK QEMU_MADV_INVALID 438#endif 439#ifdef MADV_MERGEABLE 440#define QEMU_MADV_MERGEABLE MADV_MERGEABLE 441#else 442#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID 443#endif 444#ifdef MADV_UNMERGEABLE 445#define QEMU_MADV_UNMERGEABLE MADV_UNMERGEABLE 446#else 447#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID 448#endif 449#ifdef MADV_DODUMP 450#define QEMU_MADV_DODUMP MADV_DODUMP 451#else 452#define QEMU_MADV_DODUMP QEMU_MADV_INVALID 453#endif 454#ifdef MADV_DONTDUMP 455#define QEMU_MADV_DONTDUMP MADV_DONTDUMP 456#else 457#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID 458#endif 459#ifdef MADV_HUGEPAGE 460#define QEMU_MADV_HUGEPAGE MADV_HUGEPAGE 461#else 462#define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID 463#endif 464#ifdef MADV_NOHUGEPAGE 465#define QEMU_MADV_NOHUGEPAGE MADV_NOHUGEPAGE 466#else 467#define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID 468#endif 469#ifdef MADV_REMOVE 470#define QEMU_MADV_REMOVE MADV_REMOVE 471#else 472#define QEMU_MADV_REMOVE QEMU_MADV_DONTNEED 473#endif 474 475#elif defined(CONFIG_POSIX_MADVISE) 476 477#define QEMU_MADV_WILLNEED POSIX_MADV_WILLNEED 478#define QEMU_MADV_DONTNEED POSIX_MADV_DONTNEED 479#define QEMU_MADV_DONTFORK QEMU_MADV_INVALID 480#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID 481#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID 482#define QEMU_MADV_DODUMP QEMU_MADV_INVALID 483#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID 484#define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID 485#define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID 486#define QEMU_MADV_REMOVE QEMU_MADV_DONTNEED 487 488#else /* no-op */ 489 490#define QEMU_MADV_WILLNEED QEMU_MADV_INVALID 491#define QEMU_MADV_DONTNEED QEMU_MADV_INVALID 492#define QEMU_MADV_DONTFORK QEMU_MADV_INVALID 493#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID 494#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID 495#define QEMU_MADV_DODUMP QEMU_MADV_INVALID 496#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID 497#define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID 498#define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID 499#define QEMU_MADV_REMOVE QEMU_MADV_INVALID 500 501#endif 502 503#ifdef _WIN32 504#define HAVE_CHARDEV_SERIAL 1 505#elif defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 506 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) \ 507 || defined(__GLIBC__) || defined(__APPLE__) 508#define HAVE_CHARDEV_SERIAL 1 509#endif 510 511#if defined(__linux__) || defined(__FreeBSD__) || \ 512 defined(__FreeBSD_kernel__) || defined(__DragonFly__) 513#define HAVE_CHARDEV_PARPORT 1 514#endif 515 516#if defined(__HAIKU__) 517#define SIGIO SIGPOLL 518#endif 519 520#if defined(CONFIG_LINUX) 521#ifndef BUS_MCEERR_AR 522#define BUS_MCEERR_AR 4 523#endif 524#ifndef BUS_MCEERR_AO 525#define BUS_MCEERR_AO 5 526#endif 527#endif 528 529#if defined(__linux__) && \ 530 (defined(__x86_64__) || defined(__arm__) || defined(__aarch64__) \ 531 || defined(__powerpc64__)) 532 /* Use 2 MiB alignment so transparent hugepages can be used by KVM. 533 Valgrind does not support alignments larger than 1 MiB, 534 therefore we need special code which handles running on Valgrind. */ 535# define QEMU_VMALLOC_ALIGN (512 * 4096) 536#elif defined(__linux__) && defined(__s390x__) 537 /* Use 1 MiB (segment size) alignment so gmap can be used by KVM. */ 538# define QEMU_VMALLOC_ALIGN (256 * 4096) 539#elif defined(__linux__) && defined(__sparc__) 540# define QEMU_VMALLOC_ALIGN MAX(qemu_real_host_page_size, SHMLBA) 541#else 542# define QEMU_VMALLOC_ALIGN qemu_real_host_page_size 543#endif 544 545#ifdef CONFIG_POSIX 546struct qemu_signalfd_siginfo { 547 uint32_t ssi_signo; /* Signal number */ 548 int32_t ssi_errno; /* Error number (unused) */ 549 int32_t ssi_code; /* Signal code */ 550 uint32_t ssi_pid; /* PID of sender */ 551 uint32_t ssi_uid; /* Real UID of sender */ 552 int32_t ssi_fd; /* File descriptor (SIGIO) */ 553 uint32_t ssi_tid; /* Kernel timer ID (POSIX timers) */ 554 uint32_t ssi_band; /* Band event (SIGIO) */ 555 uint32_t ssi_overrun; /* POSIX timer overrun count */ 556 uint32_t ssi_trapno; /* Trap number that caused signal */ 557 int32_t ssi_status; /* Exit status or signal (SIGCHLD) */ 558 int32_t ssi_int; /* Integer sent by sigqueue(2) */ 559 uint64_t ssi_ptr; /* Pointer sent by sigqueue(2) */ 560 uint64_t ssi_utime; /* User CPU time consumed (SIGCHLD) */ 561 uint64_t ssi_stime; /* System CPU time consumed (SIGCHLD) */ 562 uint64_t ssi_addr; /* Address that generated signal 563 (for hardware-generated signals) */ 564 uint8_t pad[48]; /* Pad size to 128 bytes (allow for 565 additional fields in the future) */ 566}; 567 568int qemu_signalfd(const sigset_t *mask); 569void sigaction_invoke(struct sigaction *action, 570 struct qemu_signalfd_siginfo *info); 571#endif 572 573int qemu_madvise(void *addr, size_t len, int advice); 574int qemu_mprotect_rw(void *addr, size_t size); 575int qemu_mprotect_rwx(void *addr, size_t size); 576int qemu_mprotect_none(void *addr, size_t size); 577 578/* 579 * Don't introduce new usage of this function, prefer the following 580 * qemu_open/qemu_create that take an "Error **errp" 581 */ 582int qemu_open_old(const char *name, int flags, ...); 583int qemu_open(const char *name, int flags, Error **errp); 584int qemu_create(const char *name, int flags, mode_t mode, Error **errp); 585int qemu_close(int fd); 586int qemu_unlink(const char *name); 587#ifndef _WIN32 588int qemu_dup_flags(int fd, int flags); 589int qemu_dup(int fd); 590int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive); 591int qemu_unlock_fd(int fd, int64_t start, int64_t len); 592int qemu_lock_fd_test(int fd, int64_t start, int64_t len, bool exclusive); 593bool qemu_has_ofd_lock(void); 594#endif 595 596#if defined(__HAIKU__) && defined(__i386__) 597#define FMT_pid "%ld" 598#elif defined(WIN64) 599#define FMT_pid "%" PRId64 600#else 601#define FMT_pid "%d" 602#endif 603 604bool qemu_write_pidfile(const char *pidfile, Error **errp); 605 606int qemu_get_thread_id(void); 607 608#ifndef CONFIG_IOVEC 609struct iovec { 610 void *iov_base; 611 size_t iov_len; 612}; 613/* 614 * Use the same value as Linux for now. 615 */ 616#define IOV_MAX 1024 617 618ssize_t readv(int fd, const struct iovec *iov, int iov_cnt); 619ssize_t writev(int fd, const struct iovec *iov, int iov_cnt); 620#endif 621 622#ifdef _WIN32 623static inline void qemu_timersub(const struct timeval *val1, 624 const struct timeval *val2, 625 struct timeval *res) 626{ 627 res->tv_sec = val1->tv_sec - val2->tv_sec; 628 if (val1->tv_usec < val2->tv_usec) { 629 res->tv_sec--; 630 res->tv_usec = val1->tv_usec - val2->tv_usec + 1000 * 1000; 631 } else { 632 res->tv_usec = val1->tv_usec - val2->tv_usec; 633 } 634} 635#else 636#define qemu_timersub timersub 637#endif 638 639void qemu_set_cloexec(int fd); 640 641/* Starting on QEMU 2.5, qemu_hw_version() returns "2.5+" by default 642 * instead of QEMU_VERSION, so setting hw_version on MachineClass 643 * is no longer mandatory. 644 * 645 * Do NOT change this string, or it will break compatibility on all 646 * machine classes that don't set hw_version. 647 */ 648#define QEMU_HW_VERSION "2.5+" 649 650/* QEMU "hardware version" setting. Used to replace code that exposed 651 * QEMU_VERSION to guests in the past and need to keep compatibility. 652 * Do not use qemu_hw_version() in new code. 653 */ 654void qemu_set_hw_version(const char *); 655const char *qemu_hw_version(void); 656 657void fips_set_state(bool requested); 658bool fips_get_state(void); 659 660/* Return a dynamically allocated pathname denoting a file or directory that is 661 * appropriate for storing local state. 662 * 663 * @relative_pathname need not start with a directory separator; one will be 664 * added automatically. 665 * 666 * The caller is responsible for releasing the value returned with g_free() 667 * after use. 668 */ 669char *qemu_get_local_state_pathname(const char *relative_pathname); 670 671/* Find program directory, and save it for later usage with 672 * qemu_get_exec_dir(). 673 * Try OS specific API first, if not working, parse from argv0. */ 674void qemu_init_exec_dir(const char *argv0); 675 676/* Get the saved exec dir. */ 677const char *qemu_get_exec_dir(void); 678 679/** 680 * qemu_getauxval: 681 * @type: the auxiliary vector key to lookup 682 * 683 * Search the auxiliary vector for @type, returning the value 684 * or 0 if @type is not present. 685 */ 686unsigned long qemu_getauxval(unsigned long type); 687 688void qemu_set_tty_echo(int fd, bool echo); 689 690void os_mem_prealloc(int fd, char *area, size_t sz, int smp_cpus, 691 Error **errp); 692 693/** 694 * qemu_get_pid_name: 695 * @pid: pid of a process 696 * 697 * For given @pid fetch its name. Caller is responsible for 698 * freeing the string when no longer needed. 699 * Returns allocated string on success, NULL on failure. 700 */ 701char *qemu_get_pid_name(pid_t pid); 702 703/** 704 * qemu_fork: 705 * 706 * A version of fork that avoids signal handler race 707 * conditions that can lead to child process getting 708 * signals that are otherwise only expected by the 709 * parent. It also resets all signal handlers to the 710 * default settings. 711 * 712 * Returns 0 to child process, pid number to parent 713 * or -1 on failure. 714 */ 715pid_t qemu_fork(Error **errp); 716 717/* Using intptr_t ensures that qemu_*_page_mask is sign-extended even 718 * when intptr_t is 32-bit and we are aligning a long long. 719 */ 720extern uintptr_t qemu_real_host_page_size; 721extern intptr_t qemu_real_host_page_mask; 722 723extern int qemu_icache_linesize; 724extern int qemu_icache_linesize_log; 725extern int qemu_dcache_linesize; 726extern int qemu_dcache_linesize_log; 727 728/* 729 * After using getopt or getopt_long, if you need to parse another set 730 * of options, then you must reset optind. Unfortunately the way to 731 * do this varies between implementations of getopt. 732 */ 733static inline void qemu_reset_optind(void) 734{ 735#ifdef HAVE_OPTRESET 736 optind = 1; 737 optreset = 1; 738#else 739 optind = 0; 740#endif 741} 742 743/** 744 * qemu_get_host_name: 745 * @errp: Error object 746 * 747 * Operating system agnostic way of querying host name. 748 * 749 * Returns allocated hostname (caller should free), NULL on failure. 750 */ 751char *qemu_get_host_name(Error **errp); 752 753/** 754 * qemu_get_host_physmem: 755 * 756 * Operating system agnostic way of querying host memory. 757 * 758 * Returns amount of physical memory on the system. This is purely 759 * advisery and may return 0 if we can't work it out. At the other 760 * end we saturate to SIZE_MAX if you are lucky enough to have that 761 * much memory. 762 */ 763size_t qemu_get_host_physmem(void); 764 765/* 766 * Toggle write/execute on the pages marked MAP_JIT 767 * for the current thread. 768 */ 769#if defined(MAC_OS_VERSION_11_0) && \ 770 MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_VERSION_11_0 771static inline void qemu_thread_jit_execute(void) 772{ 773 if (__builtin_available(macOS 11.0, *)) { 774 pthread_jit_write_protect_np(true); 775 } 776} 777 778static inline void qemu_thread_jit_write(void) 779{ 780 if (__builtin_available(macOS 11.0, *)) { 781 pthread_jit_write_protect_np(false); 782 } 783} 784#else 785static inline void qemu_thread_jit_write(void) {} 786static inline void qemu_thread_jit_execute(void) {} 787#endif 788 789/** 790 * Platforms which do not support system() return ENOSYS 791 */ 792#ifndef HAVE_SYSTEM_FUNCTION 793#define system platform_does_not_support_system 794static inline int platform_does_not_support_system(const char *command) 795{ 796 errno = ENOSYS; 797 return -1; 798} 799#endif /* !HAVE_SYSTEM_FUNCTION */ 800 801#ifdef __cplusplus 802} 803#endif 804 805#endif