Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1// SPDX-License-Identifier: GPL-2.0
2// Copyright (c) 2024, Intel Corporation
3#include <stdbool.h>
4#include <stdio.h>
5
6#define MAX_PACKED_FIELD_SIZE 50
7
8int main(int argc, char **argv)
9{
10 /* The first macro doesn't need a 'do {} while(0)' loop */
11 printf("#define CHECK_PACKED_FIELDS_1(fields) \\\n");
12 printf("\tCHECK_PACKED_FIELD(fields, 0)\n\n");
13
14 /* Remaining macros require a do/while loop, and are implemented
15 * recursively by calling the previous iteration's macro.
16 */
17 for (int i = 2; i <= MAX_PACKED_FIELD_SIZE; i++) {
18 printf("#define CHECK_PACKED_FIELDS_%d(fields) do { \\\n", i);
19 printf("\tCHECK_PACKED_FIELDS_%d(fields); \\\n", i - 1);
20 printf("\tCHECK_PACKED_FIELD(fields, %d); \\\n", i - 1);
21 printf("} while (0)\n\n");
22 }
23
24 printf("#define CHECK_PACKED_FIELDS(fields) \\\n");
25
26 for (int i = 1; i <= MAX_PACKED_FIELD_SIZE; i++)
27 printf("\t__builtin_choose_expr(ARRAY_SIZE(fields) == %d, ({ CHECK_PACKED_FIELDS_%d(fields); }), \\\n",
28 i, i);
29
30 printf("\t({ BUILD_BUG_ON_MSG(1, \"CHECK_PACKED_FIELDS() must be regenerated to support array sizes larger than %d.\"); }) \\\n",
31 MAX_PACKED_FIELD_SIZE);
32
33 for (int i = 1; i <= MAX_PACKED_FIELD_SIZE; i++)
34 printf(")");
35
36 printf("\n");
37}