diff options
Diffstat (limited to 'common/collection/collection.h')
| -rw-r--r-- | common/collection/collection.h | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/common/collection/collection.h b/common/collection/collection.h index dc59ea2f9..b4bbb2a4b 100644 --- a/common/collection/collection.h +++ b/common/collection/collection.h @@ -501,6 +501,113 @@ uint64_t col_get_item_hash(struct collection_item *ci); */ uint64_t col_make_hash(const char *string, int *length); +/* Compare two items. + * The second item is evaluated against the first. + * Function returns 0 if two items are the same + * and non-zero otherwise. + * The in_flags is a bit mask that defines + * how the items should be compared. + * See below the list of conbstants + * defined for this purpose. + * If items are different they might be orderable + * or not. For example one can order items by name + * but not by type. + * If the result of the function is non-zero + * the out_flags (if provided) will be + * set to indicate if the second item is greater + * then the first. + */ +int col_compare_items(struct collection_item *first, + struct collection_item *second, + unsigned in_flags, + unsigned *out_flags); + +/********* Possible valies for input flags ********/ +/* How to compare properties? + * The following 4 flags are mutually exclusive + */ +#define COL_CMPIN_PROP_EQU 0x000000004 /* Properties should be same */ +#define COL_CMPIN_PROP_BEG 0x000000005 /* Properties start same */ +#define COL_CMPIN_PROP_MID 0x000000006 /* One is substring of another */ +#define COL_CMPIN_PROP_END 0x000000007 /* One property ends with another */ + +/* Make sure that there is a dot. + * Useful with _BEG, _MID and _END flags to check that the there is + * a dot (if present) in the right place (before, after or both). + * For example the first item is named "foo.bar" and the second + * is "bar". Using _END the "bar" will be found but if _DOT flag is + * used too the function will also check if there was a "." before the found + * string in this case. + * Ignored in case of _EQU. + */ +#define COL_CMPIN_PROP_DOT 0x000000008 + +/* Compare property lenghts */ +#define COL_CMPIN_PROP_LEN 0x000000010 + +/* Compare types */ +#define COL_CMPIN_TYPE 0x000000020 + +/* Compare data len */ +#define COL_CMPIN_DATA_LEN 0x000000040 + +/* Compare data (up to the length of the second one) + * if type is the same. If type is different + * function will assume data is different + * without performing actual comparison. + */ +#define COL_CMPIN_DATA 0x000000080 + +/********* Possible values for output flags *********/ +/* If _EQU was specified and the property of the second item + * is greater the following bit will be set + */ +#define COL_CMPOUT_PROP_STR 0x00000001 +/* If we were told to compare property lengths + * and second is longer this bit will be set + */ +#define COL_CMPOUT_PROP_LEN 0x00000002 +/* If we were told to compare data lengths + * and second is longer this bit will be set + */ +#define COL_CMPOUT_DATA_LEN 0x00000004 +/* If we were told to compare data + * and types are the same then + * if the second one is greater this bit will + * be set. If data is binary flag is never set + */ +#define COL_CMPOUT_DATA 0x00000008 + + +/* Sort collection. + * cmp_flags are the same as in_flags for the compare + * function. The sort_flags is an OR of the costants + * defined below. + * If the subcollections are included in sorting + * each collection is sorted separately (this is not a global sort). + * It might be dangerous to sort subcollections if + * subcollection is not owned by current collection. + * If it is a reference to an external collection + * there might be an issue. To skip the collections that + * externally referenced use MYSUB flag. + * Keep in mind that if the collection + * has two references to the same other + * collection it is impossible to detect + * this situation. If MYSUB is used in this + * case such collection will be ignored + * If MYSUB is not used the collection + * will be sorted more than once. + */ +int col_sort_collection(struct collection_item *col, + unsigned cmp_flags, + unsigned sort_flags); + +/* Sort flags */ +#define COL_SORT_ASC 0x00000000 +#define COL_SORT_DESC 0x00000001 +#define COL_SORT_SUB 0x00000002 +#define COL_SORT_MYSUB 0x00000004 + /* If you want to modify the item that you got as a result of iterating through collection * or by calling col_get_item(). If you want to rename item provide a new name in the property * argument. If you want the data to remain unchanged use 0 as length parameter. |