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/* Licensed under LGPLv3+ - see LICENSE file for details */
#ifndef CCAN_FOREACH_H
#define CCAN_FOREACH_H
#include "config.h"
#include <stddef.h>
#include <assert.h>
#include <stdbool.h>
#if HAVE_COMPOUND_LITERALS
#if HAVE_FOR_LOOP_DECLARATION
/**
* foreach_int - iterate over a fixed series of integers
* @i: the int-compatible iteration variable
* ...: one or more integer-compatible values
*
* This is a convenient wrapper function for setting a variable to one or
* more explicit values in turn. continue and break work as expected.
*
* Example:
* int i;
* foreach_int(i, 0, -1, 100, 0, -99) {
* printf("i is %i\n", i);
* }
*/
#define foreach_int(i, ...) \
for (unsigned _foreach_i = (((i) = ((int[]) { __VA_ARGS__ })[0]), 0); \
_foreach_i < sizeof((int[]) { __VA_ARGS__ })/sizeof(int); \
(i) = ((int[]) { __VA_ARGS__, 0 })[++_foreach_i])
/**
* foreach_ptr - iterate over a non-NULL series of pointers
* @i: the pointer iteration variable
* ...: one or more compatible pointer values
*
* This is a convenient wrapper function for setting a variable to one
* or more explicit values in turn. None of the values can be NULL;
* that is the termination condition (ie. @i will be NULL on
* completion). continue and break work as expected.
*
* Example:
* const char *p;
* foreach_ptr(p, "Hello", "world") {
* printf("p is %s\n", p);
* }
*/
#define foreach_ptr(i, ...) \
for (unsigned _foreach_i \
= (((i) = (void *)((FOREACH_TYPEOF(i)[]){ __VA_ARGS__ })[0]), 0); \
(i); \
(i) = (void *)((FOREACH_TYPEOF(i)[]) \
{ __VA_ARGS__, NULL})[++_foreach_i], \
_foreach_no_nullval(_foreach_i, i, \
((const void *[]){ __VA_ARGS__})))
#else /* !HAVE_FOR_LOOP_DECLARATION */
/* GCC in C89 mode still has compound literals, but no for-declarations */
#define foreach_int(i, ...) \
for ((i) = ((int[]){ __VA_ARGS__ })[0], _foreach_iter_init(&(i)); \
_foreach_iter(&(i)) < sizeof((int[]) { __VA_ARGS__ }) \
/ sizeof(int); \
(i) = (int[]) { __VA_ARGS__, 0 }[_foreach_iter_inc(&(i))])
#define foreach_ptr(i, ...) \
for ((i) = (void *)((FOREACH_TYPEOF(i)[]){ __VA_ARGS__ })[0], \
_foreach_iter_init(&(i)); \
(i); \
(i) = (void *)((FOREACH_TYPEOF(i)[]){ __VA_ARGS__, NULL }) \
[_foreach_iter_inc(&(i))], \
_foreach_no_nullval(_foreach_iter(&(i)), i, \
((const void *[]){ __VA_ARGS__})))
void _foreach_iter_init(const void *i);
unsigned int _foreach_iter(const void *i);
unsigned int _foreach_iter_inc(const void *i);
#endif /* !HAVE_FOR_LOOP_DECLARATION */
/* Make sure they don't put NULL values into array! */
#define _foreach_no_nullval(i, p, arr) \
assert((i) >= sizeof(arr)/sizeof(arr[0]) || (p))
#if HAVE_TYPEOF
#define FOREACH_TYPEOF(i) __typeof__(i)
#else
#define FOREACH_TYPEOF(i) const void *
#endif
#else /* !HAVE_COMPOUND_LITERALS */
/* No compound literals, but it's still (just) possible. */
#define foreach_int(i, ...) \
for (i = _foreach_intval_init(&(i), __VA_ARGS__, _foreach_term); \
!_foreach_intval_done(&i); \
i = _foreach_intval_next(&(i), __VA_ARGS__, _foreach_term))
#define foreach_ptr(i, ...) \
for (i = _foreach_ptrval_init(&(i), __VA_ARGS__, NULL); \
(i); \
i = _foreach_ptrval_next(&(i), __VA_ARGS__, NULL))
extern int _foreach_term;
int _foreach_intval_init(const void *i, int val, ...);
bool _foreach_intval_done(const void *i);
int _foreach_intval_next(const void *i, int val, ...);
void *_foreach_ptrval_init(const void *i, const void *val, ...);
void *_foreach_ptrval_next(const void *i, const void *val, ...);
#endif /* !HAVE_COMPOUND_LITERALS */
#endif /* CCAN_FOREACH_H */
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