oslib: do not call g_strdup from qemu_get_exec_dir
[qemu.git] / 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
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 /*
501 * Don't introduce new usage of this function, prefer the following
502 * qemu_open/qemu_create that take an "Error **errp"
503 */
504 int qemu_open_old(const char *name, int flags, ...);
505 int qemu_open(const char *name, int flags, Error **errp);
506 int qemu_create(const char *name, int flags, mode_t mode, Error **errp);
507 int qemu_close(int fd);
508 int qemu_unlink(const char *name);
509 #ifndef _WIN32
510 int qemu_dup_flags(int fd, int flags);
511 int qemu_dup(int fd);
512 int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive);
513 int qemu_unlock_fd(int fd, int64_t start, int64_t len);
514 int qemu_lock_fd_test(int fd, int64_t start, int64_t len, bool exclusive);
515 bool qemu_has_ofd_lock(void);
516 #endif
517
518 #if defined(__HAIKU__) && defined(__i386__)
519 #define FMT_pid "%ld"
520 #elif defined(WIN64)
521 #define FMT_pid "%" PRId64
522 #else
523 #define FMT_pid "%d"
524 #endif
525
526 bool qemu_write_pidfile(const char *pidfile, Error **errp);
527
528 int qemu_get_thread_id(void);
529
530 #ifndef CONFIG_IOVEC
531 struct iovec {
532 void *iov_base;
533 size_t iov_len;
534 };
535 /*
536 * Use the same value as Linux for now.
537 */
538 #define IOV_MAX 1024
539
540 ssize_t readv(int fd, const struct iovec *iov, int iov_cnt);
541 ssize_t writev(int fd, const struct iovec *iov, int iov_cnt);
542 #else
543 #include <sys/uio.h>
544 #endif
545
546 #ifdef _WIN32
547 static inline void qemu_timersub(const struct timeval *val1,
548 const struct timeval *val2,
549 struct timeval *res)
550 {
551 res->tv_sec = val1->tv_sec - val2->tv_sec;
552 if (val1->tv_usec < val2->tv_usec) {
553 res->tv_sec--;
554 res->tv_usec = val1->tv_usec - val2->tv_usec + 1000 * 1000;
555 } else {
556 res->tv_usec = val1->tv_usec - val2->tv_usec;
557 }
558 }
559 #else
560 #define qemu_timersub timersub
561 #endif
562
563 void qemu_set_cloexec(int fd);
564
565 /* Starting on QEMU 2.5, qemu_hw_version() returns "2.5+" by default
566 * instead of QEMU_VERSION, so setting hw_version on MachineClass
567 * is no longer mandatory.
568 *
569 * Do NOT change this string, or it will break compatibility on all
570 * machine classes that don't set hw_version.
571 */
572 #define QEMU_HW_VERSION "2.5+"
573
574 /* QEMU "hardware version" setting. Used to replace code that exposed
575 * QEMU_VERSION to guests in the past and need to keep compatibility.
576 * Do not use qemu_hw_version() in new code.
577 */
578 void qemu_set_hw_version(const char *);
579 const char *qemu_hw_version(void);
580
581 void fips_set_state(bool requested);
582 bool fips_get_state(void);
583
584 /* Return a dynamically allocated pathname denoting a file or directory that is
585 * appropriate for storing local state.
586 *
587 * @relative_pathname need not start with a directory separator; one will be
588 * added automatically.
589 *
590 * The caller is responsible for releasing the value returned with g_free()
591 * after use.
592 */
593 char *qemu_get_local_state_pathname(const char *relative_pathname);
594
595 /* Find program directory, and save it for later usage with
596 * qemu_get_exec_dir().
597 * Try OS specific API first, if not working, parse from argv0. */
598 void qemu_init_exec_dir(const char *argv0);
599
600 /* Get the saved exec dir. */
601 const char *qemu_get_exec_dir(void);
602
603 /**
604 * qemu_getauxval:
605 * @type: the auxiliary vector key to lookup
606 *
607 * Search the auxiliary vector for @type, returning the value
608 * or 0 if @type is not present.
609 */
610 unsigned long qemu_getauxval(unsigned long type);
611
612 void qemu_set_tty_echo(int fd, bool echo);
613
614 void os_mem_prealloc(int fd, char *area, size_t sz, int smp_cpus,
615 Error **errp);
616
617 /**
618 * qemu_get_pid_name:
619 * @pid: pid of a process
620 *
621 * For given @pid fetch its name. Caller is responsible for
622 * freeing the string when no longer needed.
623 * Returns allocated string on success, NULL on failure.
624 */
625 char *qemu_get_pid_name(pid_t pid);
626
627 /**
628 * qemu_fork:
629 *
630 * A version of fork that avoids signal handler race
631 * conditions that can lead to child process getting
632 * signals that are otherwise only expected by the
633 * parent. It also resets all signal handlers to the
634 * default settings.
635 *
636 * Returns 0 to child process, pid number to parent
637 * or -1 on failure.
638 */
639 pid_t qemu_fork(Error **errp);
640
641 /* Using intptr_t ensures that qemu_*_page_mask is sign-extended even
642 * when intptr_t is 32-bit and we are aligning a long long.
643 */
644 extern uintptr_t qemu_real_host_page_size;
645 extern intptr_t qemu_real_host_page_mask;
646
647 extern int qemu_icache_linesize;
648 extern int qemu_icache_linesize_log;
649 extern int qemu_dcache_linesize;
650 extern int qemu_dcache_linesize_log;
651
652 /*
653 * After using getopt or getopt_long, if you need to parse another set
654 * of options, then you must reset optind. Unfortunately the way to
655 * do this varies between implementations of getopt.
656 */
657 static inline void qemu_reset_optind(void)
658 {
659 #ifdef HAVE_OPTRESET
660 optind = 1;
661 optreset = 1;
662 #else
663 optind = 0;
664 #endif
665 }
666
667 /**
668 * qemu_get_host_name:
669 * @errp: Error object
670 *
671 * Operating system agnostic way of querying host name.
672 *
673 * Returns allocated hostname (caller should free), NULL on failure.
674 */
675 char *qemu_get_host_name(Error **errp);
676
677 /**
678 * qemu_get_host_physmem:
679 *
680 * Operating system agnostic way of querying host memory.
681 *
682 * Returns amount of physical memory on the system. This is purely
683 * advisery and may return 0 if we can't work it out. At the other
684 * end we saturate to SIZE_MAX if you are lucky enough to have that
685 * much memory.
686 */
687 size_t qemu_get_host_physmem(void);
688
689 #endif