/*
* GLIB Compatibility Functions
*
* Copyright IBM, Corp. 2013
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
* Michael Tokarev <mjt@tls.msk.ru>
* Paolo Bonzini <pbonzini@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#ifndef QEMU_GLIB_COMPAT_H
#define QEMU_GLIB_COMPAT_H
/* Ask for warnings for anything that was marked deprecated in
* the defined version, or before. It is a candidate for rewrite.
*/
#define GLIB_VERSION_MIN_REQUIRED GLIB_VERSION_2_56
/* Ask for warnings if code tries to use function that did not
* exist in the defined version. These risk breaking builds
*/
#define GLIB_VERSION_MAX_ALLOWED GLIB_VERSION_2_56
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
#include <glib.h>
#if defined(G_OS_UNIX)
#include <glib-unix.h>
#include <sys/types.h>
#include <pwd.h>
#endif
/*
* Note that because of the GLIB_VERSION_MAX_ALLOWED constant above, allowing
* use of functions from newer GLib via this compat header needs a little
* trickery to prevent warnings being emitted.
*
* Consider a function from newer glib-X.Y that we want to use
*
* int g_foo(const char *wibble)
*
* We must define a static inline function with the same signature that does
* what we need, but with a "_compat" suffix e.g.
*
* static inline void g_foo_compat(const char *wibble)
* {
* #if GLIB_CHECK_VERSION(X, Y, 0)
* g_foo(wibble)
* #else
* g_something_equivalent_in_older_glib(wibble);
* #endif
* }
*
* The #pragma at the top of this file turns off -Wdeprecated-declarations,
* ensuring this wrapper function impl doesn't trigger the compiler warning
* about using too new glib APIs. Finally we can do
*
* #define g_foo(a) g_foo_compat(a)
*
* So now the code elsewhere in QEMU, which *does* have the
* -Wdeprecated-declarations warning active, can call g_foo(...) as normal,
* without generating warnings.
*/
/*
* g_memdup2_qemu:
* @mem: (nullable): the memory to copy.
* @byte_size: the number of bytes to copy.
*
* Allocates @byte_size bytes of memory, and copies @byte_size bytes into it
* from @mem. If @mem is %NULL it returns %NULL.
*
* This replaces g_memdup(), which was prone to integer overflows when
* converting the argument from a #gsize to a #guint.
*
* This static inline version is a backport of the new public API from
* GLib 2.68, kept internal to GLib for backport to older stable releases.
* See https://gitlab.gnome.org/GNOME/glib/-/issues/2319.
*
* Returns: (nullable): a pointer to the newly-allocated copy of the memory,
* or %NULL if @mem is %NULL.
*/
static inline gpointer g_memdup2_qemu(gconstpointer mem, gsize byte_size)
{
#if GLIB_CHECK_VERSION(2, 68, 0)
return g_memdup2(mem, byte_size);
#else
gpointer new_mem;
if (mem && byte_size != 0) {
new_mem = g_malloc(byte_size);
memcpy(new_mem, mem, byte_size);
} else {
new_mem = NULL;
}
return new_mem;
#endif
}
#define g_memdup2(m, s) g_memdup2_qemu(m, s)
#if defined(G_OS_UNIX)
/*
* Note: The fallback implementation is not MT-safe, and it returns a copy of
* the libc passwd (must be g_free() after use) but not the content. Because of
* these important differences the caller must be aware of, it's not #define for
* GLib API substitution.
*/
static inline struct passwd *
g_unix_get_passwd_entry_qemu(const gchar *user_name, GError **error)
{
#if GLIB_CHECK_VERSION(2, 64, 0)
return g_unix_get_passwd_entry(user_name, error);
#else
struct passwd *p = getpwnam(user_name);
if (!p) {
g_set_error_literal(error, G_UNIX_ERROR, 0, g_strerror(errno));
return NULL;
}
return (struct passwd *)g_memdup(p, sizeof(*p));
#endif
}
#endif /* G_OS_UNIX */
static inline bool
qemu_g_test_slow(void)
{
static int cached = -1;
if (cached == -1) {
cached = g_test_slow() || getenv("G_TEST_SLOW") != NULL;
}
return cached;
}
#undef g_test_slow
#undef g_test_thorough
#undef g_test_quick
#define g_test_slow() qemu_g_test_slow()
#define g_test_thorough() qemu_g_test_slow()
#define g_test_quick() (!qemu_g_test_slow())
#pragma GCC diagnostic pop
#ifndef G_NORETURN
#define G_NORETURN G_GNUC_NORETURN
#endif
#endif
