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 60 extern 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 HAVE_SYS_SIGNAL_H 108 #include <sys/signal.h> 109 #endif 110 111 #ifndef _WIN32 112 #include <sys/wait.h> 113 #else 114 #define WIFEXITED(x) 1 115 #define WEXITSTATUS(x) (x) 116 #endif 117 118 #ifdef _WIN32 119 #include "sysemu/os-win32.h" 120 #endif 121 122 #ifdef CONFIG_POSIX 123 #include "sysemu/os-posix.h" 124 #endif 125 126 #include "glib-compat.h" 127 #include "qemu/typedefs.h" 128 129 /* 130 * For mingw, as of v6.0.0, the function implementing the assert macro is 131 * not marked as noreturn, so the compiler cannot delete code following an 132 * assert(false) as unused. We rely on this within the code base to delete 133 * code that is unreachable when features are disabled. 134 * All supported versions of Glib's g_assert() satisfy this requirement. 135 */ 136 #ifdef __MINGW32__ 137 #undef assert 138 #define assert(x) g_assert(x) 139 #endif 140 141 /* 142 * According to waitpid man page: 143 * WCOREDUMP 144 * This macro is not specified in POSIX.1-2001 and is not 145 * available on some UNIX implementations (e.g., AIX, SunOS). 146 * Therefore, enclose its use inside #ifdef WCOREDUMP ... #endif. 147 */ 148 #ifndef WCOREDUMP 149 #define WCOREDUMP(status) 0 150 #endif 151 /* 152 * We have a lot of unaudited code that may fail in strange ways, or 153 * even be a security risk during migration, if you disable assertions 154 * at compile-time. You may comment out these safety checks if you 155 * absolutely want to disable assertion overhead, but it is not 156 * supported upstream so the risk is all yours. Meanwhile, please 157 * submit patches to remove any side-effects inside an assertion, or 158 * fixing error handling that should use Error instead of assert. 159 */ 160 #ifdef NDEBUG 161 #error building with NDEBUG is not supported 162 #endif 163 #ifdef G_DISABLE_ASSERT 164 #error building with G_DISABLE_ASSERT is not supported 165 #endif 166 167 #ifndef O_LARGEFILE 168 #define O_LARGEFILE 0 169 #endif 170 #ifndef O_BINARY 171 #define O_BINARY 0 172 #endif 173 #ifndef MAP_ANONYMOUS 174 #define MAP_ANONYMOUS MAP_ANON 175 #endif 176 #ifndef MAP_FIXED_NOREPLACE 177 #define MAP_FIXED_NOREPLACE 0 178 #endif 179 #ifndef ENOMEDIUM 180 #define ENOMEDIUM ENODEV 181 #endif 182 #if !defined(ENOTSUP) 183 #define ENOTSUP 4096 184 #endif 185 #if !defined(ECANCELED) 186 #define ECANCELED 4097 187 #endif 188 #if !defined(EMEDIUMTYPE) 189 #define EMEDIUMTYPE 4098 190 #endif 191 #if !defined(ESHUTDOWN) 192 #define ESHUTDOWN 4099 193 #endif 194 195 /* time_t may be either 32 or 64 bits depending on the host OS, and 196 * can be either signed or unsigned, so we can't just hardcode a 197 * specific maximum value. This is not a C preprocessor constant, 198 * so you can't use TIME_MAX in an #ifdef, but for our purposes 199 * this isn't a problem. 200 */ 201 202 /* The macros TYPE_SIGNED, TYPE_WIDTH, and TYPE_MAXIMUM are from 203 * Gnulib, and are under the LGPL v2.1 or (at your option) any 204 * later version. 205 */ 206 207 /* True if the real type T is signed. */ 208 #define TYPE_SIGNED(t) (!((t)0 < (t)-1)) 209 210 /* The width in bits of the integer type or expression T. 211 * Padding bits are not supported. 212 */ 213 #define TYPE_WIDTH(t) (sizeof(t) * CHAR_BIT) 214 215 /* The maximum and minimum values for the integer type T. */ 216 #define TYPE_MAXIMUM(t) \ 217 ((t) (!TYPE_SIGNED(t) \ 218 ? (t)-1 \ 219 : ((((t)1 << (TYPE_WIDTH(t) - 2)) - 1) * 2 + 1))) 220 221 #ifndef TIME_MAX 222 #define TIME_MAX TYPE_MAXIMUM(time_t) 223 #endif 224 225 /* HOST_LONG_BITS is the size of a native pointer in bits. */ 226 #if UINTPTR_MAX == UINT32_MAX 227 # define HOST_LONG_BITS 32 228 #elif UINTPTR_MAX == UINT64_MAX 229 # define HOST_LONG_BITS 64 230 #else 231 # error Unknown pointer size 232 #endif 233 234 /* Mac OSX has a <stdint.h> bug that incorrectly defines SIZE_MAX with 235 * the wrong type. Our replacement isn't usable in preprocessor 236 * expressions, but it is sufficient for our needs. */ 237 #if defined(HAVE_BROKEN_SIZE_MAX) && HAVE_BROKEN_SIZE_MAX 238 #undef SIZE_MAX 239 #define SIZE_MAX ((size_t)-1) 240 #endif 241 242 /* 243 * Two variations of MIN/MAX macros. The first is for runtime use, and 244 * evaluates arguments only once (so it is safe even with side 245 * effects), but will not work in constant contexts (such as array 246 * size declarations) because of the '{}'. The second is for constant 247 * expression use, where evaluating arguments twice is safe because 248 * the result is going to be constant anyway, but will not work in a 249 * runtime context because of a void expression where a value is 250 * expected. Thus, both gcc and clang will fail to compile if you use 251 * the wrong macro (even if the error may seem a bit cryptic). 252 * 253 * Note that neither form is usable as an #if condition; if you truly 254 * need to write conditional code that depends on a minimum or maximum 255 * determined by the pre-processor instead of the compiler, you'll 256 * have to open-code it. Sadly, Coverity is severely confused by the 257 * constant variants, so we have to dumb things down there. 258 */ 259 #undef MIN 260 #define MIN(a, b) \ 261 ({ \ 262 typeof(1 ? (a) : (b)) _a = (a), _b = (b); \ 263 _a < _b ? _a : _b; \ 264 }) 265 #undef MAX 266 #define MAX(a, b) \ 267 ({ \ 268 typeof(1 ? (a) : (b)) _a = (a), _b = (b); \ 269 _a > _b ? _a : _b; \ 270 }) 271 272 #ifdef __COVERITY__ 273 # define MIN_CONST(a, b) ((a) < (b) ? (a) : (b)) 274 # define MAX_CONST(a, b) ((a) > (b) ? (a) : (b)) 275 #else 276 # define MIN_CONST(a, b) \ 277 __builtin_choose_expr( \ 278 __builtin_constant_p(a) && __builtin_constant_p(b), \ 279 (a) < (b) ? (a) : (b), \ 280 ((void)0)) 281 # define MAX_CONST(a, b) \ 282 __builtin_choose_expr( \ 283 __builtin_constant_p(a) && __builtin_constant_p(b), \ 284 (a) > (b) ? (a) : (b), \ 285 ((void)0)) 286 #endif 287 288 /* 289 * Minimum function that returns zero only if both values are zero. 290 * Intended for use with unsigned values only. 291 */ 292 #ifndef MIN_NON_ZERO 293 #define MIN_NON_ZERO(a, b) \ 294 ({ \ 295 typeof(1 ? (a) : (b)) _a = (a), _b = (b); \ 296 _a == 0 ? _b : (_b == 0 || _b > _a) ? _a : _b; \ 297 }) 298 #endif 299 300 /* Round number down to multiple */ 301 #define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m)) 302 303 /* Round number up to multiple. Safe when m is not a power of 2 (see 304 * ROUND_UP for a faster version when a power of 2 is guaranteed) */ 305 #define QEMU_ALIGN_UP(n, m) QEMU_ALIGN_DOWN((n) + (m) - 1, (m)) 306 307 /* Check if n is a multiple of m */ 308 #define QEMU_IS_ALIGNED(n, m) (((n) % (m)) == 0) 309 310 /* n-byte align pointer down */ 311 #define QEMU_ALIGN_PTR_DOWN(p, n) \ 312 ((typeof(p))QEMU_ALIGN_DOWN((uintptr_t)(p), (n))) 313 314 /* n-byte align pointer up */ 315 #define QEMU_ALIGN_PTR_UP(p, n) \ 316 ((typeof(p))QEMU_ALIGN_UP((uintptr_t)(p), (n))) 317 318 /* Check if pointer p is n-bytes aligned */ 319 #define QEMU_PTR_IS_ALIGNED(p, n) QEMU_IS_ALIGNED((uintptr_t)(p), (n)) 320 321 /* Round number up to multiple. Requires that d be a power of 2 (see 322 * QEMU_ALIGN_UP for a safer but slower version on arbitrary 323 * numbers); works even if d is a smaller type than n. */ 324 #ifndef ROUND_UP 325 #define ROUND_UP(n, d) (((n) + (d) - 1) & -(0 ? (n) : (d))) 326 #endif 327 328 #ifndef DIV_ROUND_UP 329 #define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d)) 330 #endif 331 332 /* 333 * &(x)[0] is always a pointer - if it's same type as x then the argument is a 334 * pointer, not an array. 335 */ 336 #define QEMU_IS_ARRAY(x) (!__builtin_types_compatible_p(typeof(x), \ 337 typeof(&(x)[0]))) 338 #ifndef ARRAY_SIZE 339 #define ARRAY_SIZE(x) ((sizeof(x) / sizeof((x)[0])) + \ 340 QEMU_BUILD_BUG_ON_ZERO(!QEMU_IS_ARRAY(x))) 341 #endif 342 343 int qemu_daemon(int nochdir, int noclose); 344 void *qemu_try_memalign(size_t alignment, size_t size); 345 void *qemu_memalign(size_t alignment, size_t size); 346 void *qemu_anon_ram_alloc(size_t size, uint64_t *align, bool shared); 347 void qemu_vfree(void *ptr); 348 void qemu_anon_ram_free(void *ptr, size_t size); 349 350 #define QEMU_MADV_INVALID -1 351 352 #if defined(CONFIG_MADVISE) 353 354 #define QEMU_MADV_WILLNEED MADV_WILLNEED 355 #define QEMU_MADV_DONTNEED MADV_DONTNEED 356 #ifdef MADV_DONTFORK 357 #define QEMU_MADV_DONTFORK MADV_DONTFORK 358 #else 359 #define QEMU_MADV_DONTFORK QEMU_MADV_INVALID 360 #endif 361 #ifdef MADV_MERGEABLE 362 #define QEMU_MADV_MERGEABLE MADV_MERGEABLE 363 #else 364 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID 365 #endif 366 #ifdef MADV_UNMERGEABLE 367 #define QEMU_MADV_UNMERGEABLE MADV_UNMERGEABLE 368 #else 369 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID 370 #endif 371 #ifdef MADV_DODUMP 372 #define QEMU_MADV_DODUMP MADV_DODUMP 373 #else 374 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID 375 #endif 376 #ifdef MADV_DONTDUMP 377 #define QEMU_MADV_DONTDUMP MADV_DONTDUMP 378 #else 379 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID 380 #endif 381 #ifdef MADV_HUGEPAGE 382 #define QEMU_MADV_HUGEPAGE MADV_HUGEPAGE 383 #else 384 #define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID 385 #endif 386 #ifdef MADV_NOHUGEPAGE 387 #define QEMU_MADV_NOHUGEPAGE MADV_NOHUGEPAGE 388 #else 389 #define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID 390 #endif 391 #ifdef MADV_REMOVE 392 #define QEMU_MADV_REMOVE MADV_REMOVE 393 #else 394 #define QEMU_MADV_REMOVE QEMU_MADV_INVALID 395 #endif 396 397 #elif defined(CONFIG_POSIX_MADVISE) 398 399 #define QEMU_MADV_WILLNEED POSIX_MADV_WILLNEED 400 #define QEMU_MADV_DONTNEED POSIX_MADV_DONTNEED 401 #define QEMU_MADV_DONTFORK QEMU_MADV_INVALID 402 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID 403 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID 404 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID 405 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID 406 #define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID 407 #define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID 408 #define QEMU_MADV_REMOVE QEMU_MADV_INVALID 409 410 #else /* no-op */ 411 412 #define QEMU_MADV_WILLNEED QEMU_MADV_INVALID 413 #define QEMU_MADV_DONTNEED QEMU_MADV_INVALID 414 #define QEMU_MADV_DONTFORK QEMU_MADV_INVALID 415 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID 416 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID 417 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID 418 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID 419 #define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID 420 #define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID 421 #define QEMU_MADV_REMOVE QEMU_MADV_INVALID 422 423 #endif 424 425 #ifdef _WIN32 426 #define HAVE_CHARDEV_SERIAL 1 427 #elif defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 428 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) \ 429 || defined(__GLIBC__) || defined(__APPLE__) 430 #define HAVE_CHARDEV_SERIAL 1 431 #endif 432 433 #if defined(__linux__) || defined(__FreeBSD__) || \ 434 defined(__FreeBSD_kernel__) || defined(__DragonFly__) 435 #define HAVE_CHARDEV_PARPORT 1 436 #endif 437 438 #if defined(__HAIKU__) 439 #define SIGIO SIGPOLL 440 #endif 441 442 #if defined(CONFIG_LINUX) 443 #ifndef BUS_MCEERR_AR 444 #define BUS_MCEERR_AR 4 445 #endif 446 #ifndef BUS_MCEERR_AO 447 #define BUS_MCEERR_AO 5 448 #endif 449 #endif 450 451 #if defined(__linux__) && \ 452 (defined(__x86_64__) || defined(__arm__) || defined(__aarch64__) \ 453 || defined(__powerpc64__)) 454 /* Use 2 MiB alignment so transparent hugepages can be used by KVM. 455 Valgrind does not support alignments larger than 1 MiB, 456 therefore we need special code which handles running on Valgrind. */ 457 # define QEMU_VMALLOC_ALIGN (512 * 4096) 458 #elif defined(__linux__) && defined(__s390x__) 459 /* Use 1 MiB (segment size) alignment so gmap can be used by KVM. */ 460 # define QEMU_VMALLOC_ALIGN (256 * 4096) 461 #elif defined(__linux__) && defined(__sparc__) 462 #include <sys/shm.h> 463 # define QEMU_VMALLOC_ALIGN MAX(qemu_real_host_page_size, SHMLBA) 464 #else 465 # define QEMU_VMALLOC_ALIGN qemu_real_host_page_size 466 #endif 467 468 #ifdef CONFIG_POSIX 469 struct qemu_signalfd_siginfo { 470 uint32_t ssi_signo; /* Signal number */ 471 int32_t ssi_errno; /* Error number (unused) */ 472 int32_t ssi_code; /* Signal code */ 473 uint32_t ssi_pid; /* PID of sender */ 474 uint32_t ssi_uid; /* Real UID of sender */ 475 int32_t ssi_fd; /* File descriptor (SIGIO) */ 476 uint32_t ssi_tid; /* Kernel timer ID (POSIX timers) */ 477 uint32_t ssi_band; /* Band event (SIGIO) */ 478 uint32_t ssi_overrun; /* POSIX timer overrun count */ 479 uint32_t ssi_trapno; /* Trap number that caused signal */ 480 int32_t ssi_status; /* Exit status or signal (SIGCHLD) */ 481 int32_t ssi_int; /* Integer sent by sigqueue(2) */ 482 uint64_t ssi_ptr; /* Pointer sent by sigqueue(2) */ 483 uint64_t ssi_utime; /* User CPU time consumed (SIGCHLD) */ 484 uint64_t ssi_stime; /* System CPU time consumed (SIGCHLD) */ 485 uint64_t ssi_addr; /* Address that generated signal 486 (for hardware-generated signals) */ 487 uint8_t pad[48]; /* Pad size to 128 bytes (allow for 488 additional fields in the future) */ 489 }; 490 491 int qemu_signalfd(const sigset_t *mask); 492 void sigaction_invoke(struct sigaction *action, 493 struct qemu_signalfd_siginfo *info); 494 #endif 495 496 int qemu_madvise(void *addr, size_t len, int advice); 497 int qemu_mprotect_rwx(void *addr, size_t size); 498 int qemu_mprotect_none(void *addr, size_t size); 499 500 int qemu_open(const char *name, int flags, ...); 501 int qemu_close(int fd); 502 int qemu_unlink(const char *name); 503 #ifndef _WIN32 504 int qemu_dup(int fd); 505 #endif 506 int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive); 507 int qemu_unlock_fd(int fd, int64_t start, int64_t len); 508 int qemu_lock_fd_test(int fd, int64_t start, int64_t len, bool exclusive); 509 bool qemu_has_ofd_lock(void); 510 511 #if defined(__HAIKU__) && defined(__i386__) 512 #define FMT_pid "%ld" 513 #elif defined(WIN64) 514 #define FMT_pid "%" PRId64 515 #else 516 #define FMT_pid "%d" 517 #endif 518 519 bool qemu_write_pidfile(const char *pidfile, Error **errp); 520 521 int qemu_get_thread_id(void); 522 523 #ifndef CONFIG_IOVEC 524 struct iovec { 525 void *iov_base; 526 size_t iov_len; 527 }; 528 /* 529 * Use the same value as Linux for now. 530 */ 531 #define IOV_MAX 1024 532 533 ssize_t readv(int fd, const struct iovec *iov, int iov_cnt); 534 ssize_t writev(int fd, const struct iovec *iov, int iov_cnt); 535 #else 536 #include <sys/uio.h> 537 #endif 538 539 #ifdef _WIN32 540 static inline void qemu_timersub(const struct timeval *val1, 541 const struct timeval *val2, 542 struct timeval *res) 543 { 544 res->tv_sec = val1->tv_sec - val2->tv_sec; 545 if (val1->tv_usec < val2->tv_usec) { 546 res->tv_sec--; 547 res->tv_usec = val1->tv_usec - val2->tv_usec + 1000 * 1000; 548 } else { 549 res->tv_usec = val1->tv_usec - val2->tv_usec; 550 } 551 } 552 #else 553 #define qemu_timersub timersub 554 #endif 555 556 void qemu_set_cloexec(int fd); 557 558 /* Starting on QEMU 2.5, qemu_hw_version() returns "2.5+" by default 559 * instead of QEMU_VERSION, so setting hw_version on MachineClass 560 * is no longer mandatory. 561 * 562 * Do NOT change this string, or it will break compatibility on all 563 * machine classes that don't set hw_version. 564 */ 565 #define QEMU_HW_VERSION "2.5+" 566 567 /* QEMU "hardware version" setting. Used to replace code that exposed 568 * QEMU_VERSION to guests in the past and need to keep compatibility. 569 * Do not use qemu_hw_version() in new code. 570 */ 571 void qemu_set_hw_version(const char *); 572 const char *qemu_hw_version(void); 573 574 void fips_set_state(bool requested); 575 bool fips_get_state(void); 576 577 /* Return a dynamically allocated pathname denoting a file or directory that is 578 * appropriate for storing local state. 579 * 580 * @relative_pathname need not start with a directory separator; one will be 581 * added automatically. 582 * 583 * The caller is responsible for releasing the value returned with g_free() 584 * after use. 585 */ 586 char *qemu_get_local_state_pathname(const char *relative_pathname); 587 588 /* Find program directory, and save it for later usage with 589 * qemu_get_exec_dir(). 590 * Try OS specific API first, if not working, parse from argv0. */ 591 void qemu_init_exec_dir(const char *argv0); 592 593 /* Get the saved exec dir. 594 * 595 * The caller is responsible for releasing the value returned with g_free() 596 * after use. 597 */ 598 char *qemu_get_exec_dir(void); 599 600 /** 601 * qemu_getauxval: 602 * @type: the auxiliary vector key to lookup 603 * 604 * Search the auxiliary vector for @type, returning the value 605 * or 0 if @type is not present. 606 */ 607 unsigned long qemu_getauxval(unsigned long type); 608 609 void qemu_set_tty_echo(int fd, bool echo); 610 611 void os_mem_prealloc(int fd, char *area, size_t sz, int smp_cpus, 612 Error **errp); 613 614 /** 615 * qemu_get_pid_name: 616 * @pid: pid of a process 617 * 618 * For given @pid fetch its name. Caller is responsible for 619 * freeing the string when no longer needed. 620 * Returns allocated string on success, NULL on failure. 621 */ 622 char *qemu_get_pid_name(pid_t pid); 623 624 /** 625 * qemu_fork: 626 * 627 * A version of fork that avoids signal handler race 628 * conditions that can lead to child process getting 629 * signals that are otherwise only expected by the 630 * parent. It also resets all signal handlers to the 631 * default settings. 632 * 633 * Returns 0 to child process, pid number to parent 634 * or -1 on failure. 635 */ 636 pid_t qemu_fork(Error **errp); 637 638 /* Using intptr_t ensures that qemu_*_page_mask is sign-extended even 639 * when intptr_t is 32-bit and we are aligning a long long. 640 */ 641 extern uintptr_t qemu_real_host_page_size; 642 extern intptr_t qemu_real_host_page_mask; 643 644 extern int qemu_icache_linesize; 645 extern int qemu_icache_linesize_log; 646 extern int qemu_dcache_linesize; 647 extern int qemu_dcache_linesize_log; 648 649 /* 650 * After using getopt or getopt_long, if you need to parse another set 651 * of options, then you must reset optind. Unfortunately the way to 652 * do this varies between implementations of getopt. 653 */ 654 static inline void qemu_reset_optind(void) 655 { 656 #ifdef HAVE_OPTRESET 657 optind = 1; 658 optreset = 1; 659 #else 660 optind = 0; 661 #endif 662 } 663 664 /** 665 * qemu_get_host_name: 666 * @errp: Error object 667 * 668 * Operating system agnostic way of querying host name. 669 * 670 * Returns allocated hostname (caller should free), NULL on failure. 671 */ 672 char *qemu_get_host_name(Error **errp); 673 674 /** 675 * qemu_get_host_physmem: 676 * 677 * Operating system agnostic way of querying host memory. 678 * 679 * Returns amount of physical memory on the system. This is purely 680 * advisery and may return 0 if we can't work it out. At the other 681 * end we saturate to SIZE_MAX if you are lucky enough to have that 682 * much memory. 683 */ 684 size_t qemu_get_host_physmem(void); 685 686 #endif 687