 e71e8cc035
			
		
	
	
		e71e8cc035
		
	
	
	
	
		
			
			There are two useful macros that can be defined before including glib.h that are related to the min required glib version - GLIB_VERSION_MIN_REQUIRED When this is defined, if code uses an API that was deprecated in this version, or older, a compiler warning will be emitted. This alerts maintainers to update their code to whatever new replacement API is now recommended best practice. - GLIB_VERSION_MAX_ALLOWED When this is defined, if code uses an API that was introduced in a version that is newer than the declared version, a compiler warning will be emitted. This alerts maintainers if new code accidentally uses functionality that won't be available on some supported platforms. The GLIB_VERSION_MAX_ALLOWED constant makes it a bit harder to opt in to using specific new APIs with a GLIB_CHECK_VERSION conditional. To workaround this Pragmas can be used to temporarily turn off the -Wdeprecated-declarations compiler warning, while a static inline compat function is implemented. This workaround is illustrated with the implementation of the g_strv_contains method to satisfy the test suite. Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
		
			
				
	
	
		
			117 lines
		
	
	
		
			3.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			117 lines
		
	
	
		
			3.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * 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_40
 | |
| 
 | |
| /* 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_40
 | |
| 
 | |
| #pragma GCC diagnostic push
 | |
| #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
 | |
| 
 | |
| #include <glib.h>
 | |
| 
 | |
| /*
 | |
|  * 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 "_qemu" suffix e.g.
 | |
|  *
 | |
|  * static inline void g_foo_qemu(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_qemu(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.
 | |
|  */
 | |
| 
 | |
| static inline gboolean g_strv_contains_qemu(const gchar *const *strv,
 | |
|                                             const gchar *str)
 | |
| {
 | |
| #if GLIB_CHECK_VERSION(2, 44, 0)
 | |
|     return g_strv_contains(strv, str);
 | |
| #else
 | |
|     g_return_val_if_fail(strv != NULL, FALSE);
 | |
|     g_return_val_if_fail(str != NULL, FALSE);
 | |
| 
 | |
|     for (; *strv != NULL; strv++) {
 | |
|         if (g_str_equal(str, *strv)) {
 | |
|             return TRUE;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     return FALSE;
 | |
| #endif
 | |
| }
 | |
| #define g_strv_contains(a, b) g_strv_contains_qemu(a, b)
 | |
| 
 | |
| 
 | |
| #if defined(_WIN32) && !GLIB_CHECK_VERSION(2, 50, 0)
 | |
| /*
 | |
|  * g_poll has a problem on Windows when using
 | |
|  * timeouts < 10ms, so use wrapper.
 | |
|  */
 | |
| #define g_poll(fds, nfds, timeout) g_poll_fixed(fds, nfds, timeout)
 | |
| gint g_poll_fixed(GPollFD *fds, guint nfds, gint timeout);
 | |
| #endif
 | |
| 
 | |
| 
 | |
| #ifndef g_assert_cmpmem
 | |
| #define g_assert_cmpmem(m1, l1, m2, l2)                                        \
 | |
|     do {                                                                       \
 | |
|         gconstpointer __m1 = m1, __m2 = m2;                                    \
 | |
|         int __l1 = l1, __l2 = l2;                                              \
 | |
|         if (__l1 != __l2) {                                                    \
 | |
|             g_assertion_message_cmpnum(                                        \
 | |
|                 G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC,                   \
 | |
|                 #l1 " (len(" #m1 ")) == " #l2 " (len(" #m2 "))", __l1, "==",   \
 | |
|                 __l2, 'i');                                                    \
 | |
|         } else if (memcmp(__m1, __m2, __l1) != 0) {                            \
 | |
|             g_assertion_message(G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC,   \
 | |
|                                 "assertion failed (" #m1 " == " #m2 ")");      \
 | |
|         }                                                                      \
 | |
|     } while (0)
 | |
| #endif
 | |
| 
 | |
| #pragma GCC diagnostic pop
 | |
| 
 | |
| #endif
 |