nbd: support feature negotiation

[qemu.git] / osdep.h

#ifndef QEMU_OSDEP_H
#define QEMU_OSDEP_H

#include <stdarg.h>
#include <stddef.h>
#ifdef __OpenBSD__
#include <sys/types.h>
#include <sys/signal.h>
#endif

#include <sys/time.h>

#ifndef glue
#define xglue(x, y) x ## y
#define glue(x, y) xglue(x, y)
#define stringify(s)	tostring(s)
#define tostring(s)	#s
#endif

#ifndef likely
#if __GNUC__ < 3
#define __builtin_expect(x, n) (x)
#endif

#define likely(x)   __builtin_expect(!!(x), 1)
#define unlikely(x)   __builtin_expect(!!(x), 0)
#endif

#ifdef CONFIG_NEED_OFFSETOF
#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *) 0)->MEMBER)
#endif
#ifndef container_of
#define container_of(ptr, type, member) ({                      \
        const typeof(((type *) 0)->member) *__mptr = (ptr);     \
        (type *) ((char *) __mptr - offsetof(type, member));})
#endif

/* Convert from a base type to a parent type, with compile time checking.  */
#ifdef __GNUC__
#define DO_UPCAST(type, field, dev) ( __extension__ ( { \
    char __attribute__((unused)) offset_must_be_zero[ \
        -offsetof(type, field)]; \
    container_of(dev, type, field);}))
#else
#define DO_UPCAST(type, field, dev) container_of(dev, type, field)
#endif

#define typeof_field(type, field) typeof(((type *)0)->field)
#define type_check(t1,t2) ((t1*)0 - (t2*)0)

#ifndef MIN
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
#endif
#ifndef MAX
#define MAX(a, b) (((a) > (b)) ? (a) : (b))
#endif

#ifndef DIV_ROUND_UP
#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
#endif

#ifndef ARRAY_SIZE
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
#endif

#ifndef always_inline
#if !((__GNUC__ < 3) || defined(__APPLE__))
#ifdef __OPTIMIZE__
#define inline __attribute__ (( always_inline )) __inline__
#endif
#endif
#else
#define inline always_inline
#endif

#ifdef __i386__
#define REGPARM __attribute((regparm(3)))
#else
#define REGPARM
#endif

#define qemu_printf printf

#if defined (__GNUC__) && defined (__GNUC_MINOR__)
# define QEMU_GNUC_PREREQ(maj, min) \
         ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
#else
# define QEMU_GNUC_PREREQ(maj, min) 0
#endif

int qemu_daemon(int nochdir, int noclose);
void *qemu_memalign(size_t alignment, size_t size);
void *qemu_vmalloc(size_t size);
void qemu_vfree(void *ptr);

#define QEMU_MADV_INVALID -1

#if defined(CONFIG_MADVISE)

#define QEMU_MADV_WILLNEED  MADV_WILLNEED
#define QEMU_MADV_DONTNEED  MADV_DONTNEED
#ifdef MADV_DONTFORK
#define QEMU_MADV_DONTFORK  MADV_DONTFORK
#else
#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
#endif
#ifdef MADV_MERGEABLE
#define QEMU_MADV_MERGEABLE MADV_MERGEABLE
#else
#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
#endif

#elif defined(CONFIG_POSIX_MADVISE)

#define QEMU_MADV_WILLNEED  POSIX_MADV_WILLNEED
#define QEMU_MADV_DONTNEED  POSIX_MADV_DONTNEED
#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID

#else /* no-op */

#define QEMU_MADV_WILLNEED  QEMU_MADV_INVALID
#define QEMU_MADV_DONTNEED  QEMU_MADV_INVALID
#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID

#endif

int qemu_madvise(void *addr, size_t len, int advice);

#if defined(__HAIKU__) && defined(__i386__)
#define FMT_pid "%ld"
#elif defined(WIN64)
#define FMT_pid "%" PRId64
#else
#define FMT_pid "%d"
#endif

int qemu_create_pidfile(const char *filename);
int qemu_get_thread_id(void);

#ifdef _WIN32
static inline void qemu_timersub(const struct timeval *val1,
                                 const struct timeval *val2,
                                 struct timeval *res)
{
    res->tv_sec = val1->tv_sec - val2->tv_sec;
    if (val1->tv_usec < val2->tv_usec) {
        res->tv_sec--;
        res->tv_usec = val1->tv_usec - val2->tv_usec + 1000 * 1000;
    } else {
        res->tv_usec = val1->tv_usec - val2->tv_usec;
    }
}
#else
#define qemu_timersub timersub
#endif

#endif