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#ifndef CCAN_STRSET_H
#define CCAN_STRSET_H
#include "config.h"
#include <ccan/typesafe_cb/typesafe_cb.h>
#include <stdlib.h>
#include <stdbool.h>
/**
* struct strset - representation of a string set
*
* It's exposed here to allow you to embed it and so we can inline the
* trivial functions.
*/
struct strset {
union {
struct node *n;
const char *s;
} u;
};
/**
* strset_init - initialize a string set (empty)
*
* For completeness; if you've arranged for it to be NULL already you don't
* need this.
*
* Example:
* struct strset set;
*
* strset_init(&set);
*/
static inline void strset_init(struct strset *set)
{
set->u.n = NULL;
}
/**
* strset_empty - is this string set empty?
* @set: the set.
*
* Example:
* if (!strset_empty(&set))
* abort();
*/
static inline bool strset_empty(const struct strset *set)
{
return set->u.n == NULL;
}
/**
* strset_get - is this a member of this string set?
* @set: the set.
* @member: the string to search for.
*
* Returns the member, or NULL if it isn't in the set (and sets errno
* = ENOENT).
*
* Example:
* if (strset_get(&set, "hello"))
* printf("hello is in the set\n");
*/
char *strset_get(const struct strset *set, const char *member);
/**
* strset_add - place a member in the string set.
* @set: the set.
* @member: the string to place in the set.
*
* This returns false if we run out of memory (errno = ENOMEM), or
* (more normally) if that string already appears in the set (EEXIST).
*
* Note that the pointer is placed in the set, the string is not copied. If
* you want a copy in the set, use strdup().
*
* Example:
* if (!strset_add(&set, "goodbye"))
* printf("goodbye was already in the set\n");
*/
bool strset_add(struct strset *set, const char *member);
/**
* strset_del - remove a member from the string set.
* @set: the set.
* @member: the string to remove from the set.
*
* This returns the string which was passed to strset_add(), or NULL if
* the string was not in the map (in which case it sets errno = ENOENT).
*
* This means that if you allocated a string (eg. using strdup()), you can
* free it here.
*
* Example:
* if (!strset_del(&set, "goodbye"))
* printf("goodbye was not in the set?\n");
*/
char *strset_del(struct strset *set, const char *member);
/**
* strset_clear - remove every member from the set.
* @set: the set.
*
* The set will be empty after this.
*
* Example:
* strset_clear(&set);
*/
void strset_clear(struct strset *set);
/**
* strset_iterate - ordered iteration over a set
* @set: the set.
* @handle: the function to call.
* @arg: the argument for the function (types should match).
*
* You should not alter the set within the @handle function! If it returns
* false, the iteration will stop.
*
* Example:
* static bool dump_some(const char *member, int *num)
* {
* // Only dump out num nodes.
* if (*(num--) == 0)
* return false;
* printf("%s\n", member);
* return true;
* }
*
* static void dump_set(const struct strset *set)
* {
* int max = 100;
* strset_iterate(set, dump_some, &max);
* if (max < 0)
* printf("... (truncated to 100 entries)\n");
* }
*/
#define strset_iterate(set, handle, arg) \
strset_iterate_((set), typesafe_cb_preargs(bool, void *, \
(handle), (arg), \
const char *), \
(arg))
void strset_iterate_(const struct strset *set,
bool (*handle)(const char *, void *), const void *data);
/**
* strset_prefix - return a subset matching a prefix
* @set: the set.
* @prefix: the prefix.
*
* This returns a pointer into @set, so don't alter @set while using
* the return value. You can use strset_iterate(), strset_test() or
* strset_empty() on the returned pointer.
*
* Example:
* static void dump_prefix(const struct strset *set, const char *prefix)
* {
* int max = 100;
* printf("Nodes with prefix %s:\n", prefix);
* strset_iterate(strset_prefix(set, prefix), dump_some, &max);
* if (max < 0)
* printf("... (truncated to 100 entries)\n");
* }
*/
const struct strset *strset_prefix(const struct strset *set,
const char *prefix);
#endif /* CCAN_STRSET_H */
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