qemu-e2k/include/qemu/compiler.h
Daniel P. Berrange a31bdae5a7 qom: Add object_new_with_props() / object_new_withpropv() helpers
It is reasonably common to want to create an object, set a
number of properties, register it in the hierarchy and then
mark it as complete (if a user creatable type). This requires
quite a lot of error prone, verbose, boilerplate code to achieve.

First a pair of functions object_set_props() / object_set_propv()
are added which allow for a list of objects to be set in
one single API call.

Then object_new_with_props() / object_new_with_propv() constructors
are added which simplify the sequence of calls to create an
object, populate properties, register in the object composition
tree and mark the object complete, into a single method call.

Usage would be:

   Error *err = NULL;
   Object *obj;
   obj = object_new_with_propv(TYPE_MEMORY_BACKEND_FILE,
                               object_get_objects_root(),
                               "hostmem0",
                               &err,
                               "share", "yes",
                               "mem-path", "/dev/shm/somefile",
                               "prealloc", "yes",
                               "size", "1048576",
                               NULL);

Note all property values are passed in string form and will
be parsed into their required data types, using normal QOM
semantics for parsing from string format.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
2015-06-19 18:42:18 +02:00

68 lines
1.9 KiB
C

/* public domain */
#ifndef COMPILER_H
#define COMPILER_H
#include "config-host.h"
/*----------------------------------------------------------------------------
| The macro QEMU_GNUC_PREREQ tests for minimum version of the GNU C compiler.
| The code is a copy of SOFTFLOAT_GNUC_PREREQ, see softfloat-macros.h.
*----------------------------------------------------------------------------*/
#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
#define QEMU_NORETURN __attribute__ ((__noreturn__))
#if QEMU_GNUC_PREREQ(3, 4)
#define QEMU_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
#else
#define QEMU_WARN_UNUSED_RESULT
#endif
#if QEMU_GNUC_PREREQ(4, 0)
#define QEMU_SENTINEL __attribute__((sentinel))
#else
#define QEMU_SENTINEL
#endif
#if QEMU_GNUC_PREREQ(4, 3)
#define QEMU_ARTIFICIAL __attribute__((always_inline, artificial))
#else
#define QEMU_ARTIFICIAL
#endif
#if defined(_WIN32)
# define QEMU_PACKED __attribute__((gcc_struct, packed))
#else
# define QEMU_PACKED __attribute__((packed))
#endif
#define cat(x,y) x ## y
#define cat2(x,y) cat(x,y)
#define QEMU_BUILD_BUG_ON(x) \
typedef char cat2(qemu_build_bug_on__,__LINE__)[(x)?-1:1] __attribute__((unused));
#if defined __GNUC__
# if !QEMU_GNUC_PREREQ(4, 4)
/* gcc versions before 4.4.x don't support gnu_printf, so use printf. */
# define GCC_FMT_ATTR(n, m) __attribute__((format(printf, n, m)))
# else
/* Use gnu_printf when supported (qemu uses standard format strings). */
# define GCC_FMT_ATTR(n, m) __attribute__((format(gnu_printf, n, m)))
# if defined(_WIN32)
/* Map __printf__ to __gnu_printf__ because we want standard format strings
* even when MinGW or GLib include files use __printf__. */
# define __printf__ __gnu_printf__
# endif
# endif
#else
#define GCC_FMT_ATTR(n, m)
#endif
#endif /* COMPILER_H */