a8d7d971b1
This is the version of CCAN which CLN was using at the time these were taken. Unfortunately lots of whitespace has been changed, but AFAICT no source changes. Here's the command I ran (with ../ccan checked out to 1ae4c432): ``` make update-ccan CCAN_NEW="alignof array_size build_assert check_type container_of cppmagic likely list mem short_types str structeq take tal tal/str typesafe_cb utf8 endian crypto/sha256" ``` Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: William Casarin <jb55@jb55.com>
50 lines
1.3 KiB
Plaintext
50 lines
1.3 KiB
Plaintext
#include "config.h"
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#include <stdio.h>
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#include <string.h>
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/**
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* build_assert - routines for build-time assertions
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*
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* This code provides routines which will cause compilation to fail should some
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* assertion be untrue: such failures are preferable to run-time assertions,
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* but much more limited since they can only depends on compile-time constants.
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*
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* These assertions are most useful when two parts of the code must be kept in
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* sync: it is better to avoid such cases if possible, but seconds best is to
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* detect invalid changes at build time.
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*
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* For example, a tricky piece of code might rely on a certain element being at
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* the start of the structure. To ensure that future changes don't break it,
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* you would catch such changes in your code like so:
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*
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* Example:
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* #include <stddef.h>
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* #include <ccan/build_assert/build_assert.h>
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*
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* struct foo {
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* char string[5];
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* int x;
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* };
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*
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* static char *foo_string(struct foo *foo)
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* {
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* // This trick requires that the string be first in the structure
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* BUILD_ASSERT(offsetof(struct foo, string) == 0);
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* return (char *)foo;
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* }
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*
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* License: CC0 (Public domain)
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* Author: Rusty Russell <rusty@rustcorp.com.au>
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*/
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int main(int argc, char *argv[])
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{
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if (argc != 2)
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return 1;
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if (strcmp(argv[1], "depends") == 0)
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/* Nothing. */
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return 0;
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return 1;
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}
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