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Simon McVittie authoredSimon McVittie authored
glnx-macros.h 9.11 KiB
/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*-
*
* Copyright (C) 2017 Colin Walters <walters@verbum.org>
* With original source from systemd:
* Copyright 2010 Lennart Poettering
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#pragma once
#include <stdlib.h>
#include <string.h>
#include <gio/gio.h>
G_BEGIN_DECLS
/* All of these are for C only. */
#ifndef __GI_SCANNER__
/* Taken from https://github.com/systemd/systemd/src/basic/string-util.h
* at revision v228-666-gcf6c8c4
*/
#define glnx_strjoina(a, ...) \
({ \
const char *_appendees_[] = { a, __VA_ARGS__ }; \
char *_d_, *_p_; \
size_t _len_ = 0; \
unsigned _i_; \
for (_i_ = 0; _i_ < G_N_ELEMENTS(_appendees_) && _appendees_[_i_]; _i_++) \
_len_ += strlen(_appendees_[_i_]); \
_p_ = _d_ = alloca(_len_ + 1); \
for (_i_ = 0; _i_ < G_N_ELEMENTS(_appendees_) && _appendees_[_i_]; _i_++) \
_p_ = stpcpy(_p_, _appendees_[_i_]); \
*_p_ = 0; \
_d_; \
})
#ifndef G_IN_SET
/* Infrastructure for `G_IN_SET`; this code is copied from
* systemd's macro.h - please treat that version as canonical
* and submit patches first to systemd.
*/
#define _G_INSET_CASE_F(X) case X:
#define _G_INSET_CASE_F_1(CASE, X) _G_INSET_CASE_F(X)
#define _G_INSET_CASE_F_2(CASE, X, ...) CASE(X) _G_INSET_CASE_F_1(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_3(CASE, X, ...) CASE(X) _G_INSET_CASE_F_2(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_4(CASE, X, ...) CASE(X) _G_INSET_CASE_F_3(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_5(CASE, X, ...) CASE(X) _G_INSET_CASE_F_4(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_6(CASE, X, ...) CASE(X) _G_INSET_CASE_F_5(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_7(CASE, X, ...) CASE(X) _G_INSET_CASE_F_6(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_8(CASE, X, ...) CASE(X) _G_INSET_CASE_F_7(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_9(CASE, X, ...) CASE(X) _G_INSET_CASE_F_8(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_10(CASE, X, ...) CASE(X) _G_INSET_CASE_F_9(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_11(CASE, X, ...) CASE(X) _G_INSET_CASE_F_10(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_12(CASE, X, ...) CASE(X) _G_INSET_CASE_F_11(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_13(CASE, X, ...) CASE(X) _G_INSET_CASE_F_12(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_14(CASE, X, ...) CASE(X) _G_INSET_CASE_F_13(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_15(CASE, X, ...) CASE(X) _G_INSET_CASE_F_14(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_16(CASE, X, ...) CASE(X) _G_INSET_CASE_F_15(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_17(CASE, X, ...) CASE(X) _G_INSET_CASE_F_16(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_18(CASE, X, ...) CASE(X) _G_INSET_CASE_F_17(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_19(CASE, X, ...) CASE(X) _G_INSET_CASE_F_18(CASE, __VA_ARGS__)
#define _G_INSET_CASE_F_20(CASE, X, ...) CASE(X) _G_INSET_CASE_F_19(CASE, __VA_ARGS__)
#define _G_INSET_GET_CASE_F(_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,_11,_12,_13,_14,_15,_16,_17,_18,_19,_20,NAME,...) NAME
#define _G_INSET_FOR_EACH_MAKE_CASE(...) \
_G_INSET_GET_CASE_F(__VA_ARGS__,_G_INSET_CASE_F_20,_G_INSET_CASE_F_19,_G_INSET_CASE_F_18,_G_INSET_CASE_F_17,_G_INSET_CASE_F_16,_G_INSET_CASE_F_15,_G_INSET_CASE_F_14,_G_INSET_CASE_F_13,_G_INSET_CASE_F_12,_G_INSET_CASE_F_11, \
_G_INSET_CASE_F_10,_G_INSET_CASE_F_9,_G_INSET_CASE_F_8,_G_INSET_CASE_F_7,_G_INSET_CASE_F_6,_G_INSET_CASE_F_5,_G_INSET_CASE_F_4,_G_INSET_CASE_F_3,_G_INSET_CASE_F_2,_G_INSET_CASE_F_1) \
(_G_INSET_CASE_F,__VA_ARGS__)
/* Note: claiming the name here even though it isn't upstream yet
* https://bugzilla.gnome.org/show_bug.cgi?id=783751
*/
/**
* G_IN_SET:
* @x: Integer (or smaller) sized value
* @...: Elements to compare
*
* It's quite common to test whether or not `char` values or Unix @errno (among) others
* are members of a small set. Normally one has to choose to either use `if (x == val || x == otherval ...)`
* or a `switch` statement. This macro is useful to reduce duplication in the first case,
* where one can write simply `if (G_IN_SET (x, val, otherval))`, and avoid the verbosity
* that the `switch` statement requires.
*/
#define G_IN_SET(x, ...) \
({ \
gboolean _g_inset_found = FALSE; \
/* If the build breaks in the line below, you need to extend the case macros */ \
static G_GNUC_UNUSED char _static_assert__macros_need_to_be_extended[20 - sizeof((int[]){__VA_ARGS__})/sizeof(int)]; \
switch(x) { \
_G_INSET_FOR_EACH_MAKE_CASE(__VA_ARGS__) \
_g_inset_found = TRUE; \
break; \
default: \
break; \
} \
_g_inset_found; \
})
#endif /* ifndef G_IN_SET */
#define _GLNX_CONCAT(a, b) a##b
#define _GLNX_CONCAT_INDIRECT(a, b) _GLNX_CONCAT(a, b)
#define _GLNX_MAKE_ANONYMOUS(a) _GLNX_CONCAT_INDIRECT(a, __COUNTER__)
#define _GLNX_HASH_TABLE_FOREACH_IMPL_KV(guard, ht, it, kt, k, vt, v) \
gboolean guard = TRUE; \
G_STATIC_ASSERT (sizeof (kt) == sizeof (void*)); \
G_STATIC_ASSERT (sizeof (vt) == sizeof (void*)); \
for (GHashTableIter it; \
guard && ({ g_hash_table_iter_init (&it, ht), TRUE; }); \
guard = FALSE) \
for (kt k; guard; guard = FALSE) \
for (vt v; g_hash_table_iter_next (&it, (gpointer)&k, (gpointer)&v);)
/* Cleaner method to iterate over a GHashTable. I.e. rather than
*
* gpointer k, v;
* GHashTableIter it;
* g_hash_table_iter_init (&it, table);
* while (g_hash_table_iter_next (&it, &k, &v))
* {
* const char *str = k;
* GPtrArray *arr = v;
* ...
* }
*
* you can simply do
*
* GLNX_HASH_TABLE_FOREACH_IT (table, it, const char*, str, GPtrArray*, arr)
* {
* ...
* }
*
* All variables are scoped within the loop. You may use the `it` variable as
* usual, e.g. to remove an element using g_hash_table_iter_remove(&it). There
* are shorter variants for the more common cases where you do not need access
* to the iterator or to keys/values:
*
* GLNX_HASH_TABLE_FOREACH (table, const char*, str) { ... }
* GLNX_HASH_TABLE_FOREACH_V (table, MyData*, data) { ... }
* GLNX_HASH_TABLE_FOREACH_KV (table, const char*, str, MyData*, data) { ... }
*
*/
#define GLNX_HASH_TABLE_FOREACH_IT(ht, it, kt, k, vt, v) \
_GLNX_HASH_TABLE_FOREACH_IMPL_KV( \
_GLNX_MAKE_ANONYMOUS(_glnx_ht_iter_guard_), ht, it, kt, k, vt, v)
/* Variant of GLNX_HASH_TABLE_FOREACH without having to specify an iterator. An
* anonymous iterator will be created. */
#define GLNX_HASH_TABLE_FOREACH_KV(ht, kt, k, vt, v) \
_GLNX_HASH_TABLE_FOREACH_IMPL_KV( \
_GLNX_MAKE_ANONYMOUS(_glnx_ht_iter_guard_), ht, \
_GLNX_MAKE_ANONYMOUS(_glnx_ht_iter_it_), kt, k, vt, v)
/* Variant of GLNX_HASH_TABLE_FOREACH_KV which omits unpacking keys. */
#define GLNX_HASH_TABLE_FOREACH_V(ht, vt, v) \
_GLNX_HASH_TABLE_FOREACH_IMPL_KV( \
_GLNX_MAKE_ANONYMOUS(_glnx_ht_iter_guard_), ht, \
_GLNX_MAKE_ANONYMOUS(_glnx_ht_iter_it_), \
gpointer, _GLNX_MAKE_ANONYMOUS(_glnx_ht_iter_v_), \
vt, v)
/* Variant of GLNX_HASH_TABLE_FOREACH_KV which omits unpacking vals. */
#define GLNX_HASH_TABLE_FOREACH(ht, kt, k) \
_GLNX_HASH_TABLE_FOREACH_IMPL_KV( \
_GLNX_MAKE_ANONYMOUS(_glnx_ht_iter_guard_), ht, \
_GLNX_MAKE_ANONYMOUS(_glnx_ht_iter_it_), kt, k, \
gpointer, _GLNX_MAKE_ANONYMOUS(_glnx_ht_iter_v_))
#endif /* GI_SCANNER */
G_END_DECLS