/* * 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