git/oidset.h

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#ifndef OIDSET_H
#define OIDSET_H
/**
* This API is similar to sha1-array, in that it maintains a set of object ids
* in a memory-efficient way. The major differences are:
*
* 1. It uses a hash, so we can do online duplicate removal, rather than
* sort-and-uniq at the end. This can reduce memory footprint if you have
* a large list of oids with many duplicates.
*
* 2. The per-unique-oid memory footprint is slightly higher due to hash
* table overhead.
*/
/**
* A single oidset; should be zero-initialized (or use OIDSET_INIT).
*/
struct oidset {
struct hashmap map;
};
#define OIDSET_INIT { { NULL } }
/**
* Returns true iff `set` contains `oid`.
*/
int oidset_contains(const struct oidset *set, const struct object_id *oid);
/**
* Insert the oid into the set; a copy is made, so "oid" does not need
* to persist after this function is called.
*
* Returns 1 if the oid was already in the set, 0 otherwise. This can be used
* to perform an efficient check-and-add.
*/
int oidset_insert(struct oidset *set, const struct object_id *oid);
/**
* Remove all entries from the oidset, freeing any resources associated with
* it.
*/
void oidset_clear(struct oidset *set);
#endif /* OIDSET_H */