1 /* 2 * GLIB Compatibility Functions 3 * 4 * Copyright IBM, Corp. 2013 5 * 6 * Authors: 7 * Anthony Liguori <aliguori@us.ibm.com> 8 * Michael Tokarev <mjt@tls.msk.ru> 9 * Paolo Bonzini <pbonzini@redhat.com> 10 * 11 * This work is licensed under the terms of the GNU GPL, version 2 or later. 12 * See the COPYING file in the top-level directory. 13 * 14 */ 15 16 #ifndef QEMU_GLIB_COMPAT_H 17 #define QEMU_GLIB_COMPAT_H 18 19 /* Ask for warnings for anything that was marked deprecated in 20 * the defined version, or before. It is a candidate for rewrite. 21 */ 22 #define GLIB_VERSION_MIN_REQUIRED GLIB_VERSION_2_66 23 24 /* Ask for warnings if code tries to use function that did not 25 * exist in the defined version. These risk breaking builds 26 */ 27 #define GLIB_VERSION_MAX_ALLOWED GLIB_VERSION_2_66 28 29 #pragma GCC diagnostic push 30 #pragma GCC diagnostic ignored "-Wdeprecated-declarations" 31 32 #include <glib.h> 33 #if defined(G_OS_UNIX) 34 #include <glib-unix.h> 35 #include <sys/types.h> 36 #include <pwd.h> 37 #endif 38 39 /* 40 * These functions perform function pointer casts which can cause function call 41 * failure on Emscripten. Use g_slist_sort_with_data and g_list_sort_with_data 42 * instead of these functions. 43 */ 44 #pragma GCC poison g_slist_sort g_list_sort 45 46 /* 47 * Note that because of the GLIB_VERSION_MAX_ALLOWED constant above, allowing 48 * use of functions from newer GLib via this compat header needs a little 49 * trickery to prevent warnings being emitted. 50 * 51 * Consider a function from newer glib-X.Y that we want to use 52 * 53 * int g_foo(const char *wibble) 54 * 55 * We must define a static inline function with the same signature that does 56 * what we need, but with a "_compat" suffix e.g. 57 * 58 * static inline void g_foo_compat(const char *wibble) 59 * { 60 * #if GLIB_CHECK_VERSION(X, Y, 0) 61 * g_foo(wibble) 62 * #else 63 * g_something_equivalent_in_older_glib(wibble); 64 * #endif 65 * } 66 * 67 * The #pragma at the top of this file turns off -Wdeprecated-declarations, 68 * ensuring this wrapper function impl doesn't trigger the compiler warning 69 * about using too new glib APIs. Finally we can do 70 * 71 * #define g_foo(a) g_foo_compat(a) 72 * 73 * So now the code elsewhere in QEMU, which *does* have the 74 * -Wdeprecated-declarations warning active, can call g_foo(...) as normal, 75 * without generating warnings. 76 */ 77 78 /* 79 * g_memdup2_qemu: 80 * @mem: (nullable): the memory to copy. 81 * @byte_size: the number of bytes to copy. 82 * 83 * Allocates @byte_size bytes of memory, and copies @byte_size bytes into it 84 * from @mem. If @mem is %NULL it returns %NULL. 85 * 86 * This replaces g_memdup(), which was prone to integer overflows when 87 * converting the argument from a #gsize to a #guint. 88 * 89 * This static inline version is a backport of the new public API from 90 * GLib 2.68, kept internal to GLib for backport to older stable releases. 91 * See https://gitlab.gnome.org/GNOME/glib/-/issues/2319. 92 * 93 * Returns: (nullable): a pointer to the newly-allocated copy of the memory, 94 * or %NULL if @mem is %NULL. 95 */ 96 static inline gpointer g_memdup2_qemu(gconstpointer mem, gsize byte_size) 97 { 98 #if GLIB_CHECK_VERSION(2, 68, 0) 99 return g_memdup2(mem, byte_size); 100 #else 101 gpointer new_mem; 102 103 if (mem && byte_size != 0) { 104 new_mem = g_malloc(byte_size); 105 memcpy(new_mem, mem, byte_size); 106 } else { 107 new_mem = NULL; 108 } 109 110 return new_mem; 111 #endif 112 } 113 #define g_memdup2(m, s) g_memdup2_qemu(m, s) 114 115 static inline bool 116 qemu_g_test_slow(void) 117 { 118 static int cached = -1; 119 if (cached == -1) { 120 cached = g_test_slow() || getenv("G_TEST_SLOW") != NULL; 121 } 122 return cached; 123 } 124 125 #undef g_test_slow 126 #undef g_test_thorough 127 #undef g_test_quick 128 #define g_test_slow() qemu_g_test_slow() 129 #define g_test_thorough() qemu_g_test_slow() 130 #define g_test_quick() (!qemu_g_test_slow()) 131 132 #pragma GCC diagnostic pop 133 134 #ifndef G_NORETURN 135 #define G_NORETURN G_GNUC_NORETURN 136 #endif 137 138 #endif 139