Introduce `HshIdx`

Introduce `HshIdx`, a multi-dimensional HashTable.
WARN: Early draft, not really usable yet.

1 files changed, 34 insertions, 0 deletions

diff --git a/include/qntan/Qntan.h b/include/qntan/Qntan.h
index e159546..d5e77a7 100644
--- a/include/qntan/Qntan.h
+++ b/include/qntan/Qntan.h
@@ -73,6 +73,7 @@ struct Qntan_FileSystem_Dirent;
 struct Qntan_FileSystem;
 struct Qntan_FourierTransform;
 struct Qntan_Process;
+struct Qntan_HshIdx;
 struct Qntan_HshTbl;
 struct Qntan_HshTbl_Cursor;
 struct Qntan_Socket;
@@ -819,6 +820,39 @@ struct Qntan_Process {
 
 
 
+struct Qntan_HshIdx {
+	/* An n-dimensional HashTable. Where as many properties as wanted
+	 * can be used to index into the table.
+	 * BUT: ONLY the 1st index is considered to be unique (for
+	 * consistency reasons, only ONE index can be used to decide if an
+	 * object already exists for exmaple. Allowing multiple would cause
+	 * conflicts as soon indexes disagree in such a case).
+	 */
+	size_t (*getCnt)( struct Qntan_HshIdx** );
+	/* Returns number of objects currently present in this collection.
+	 */
+	int  (*addIfNew)( struct Qntan_HshIdx**, void*elm );
+	/* Returns 0 if 'elm' got copied into the hashtable.
+	 * Returns '-EEXIST' (yep, negated) if 'elm' already exists. Nothing got
+	 * copied anywhere.
+	 * Returns negative values to indicate errors.
+	 */
+	int  (*get)( struct Qntan_HshIdx**, void*srch, void*ptrToDst, int idx );
+	/* Returns 0 if there's no object matching 'srch'.
+	 * Returns 1 if found object got copied to 'ptrToDst'. The element itelf
+	 * will swill be present in the table.
+	 */
+};
+
+
+
+
+
+
+
+
+
+
 struct Qntan_HshTbl {
 	/**/
 	int  (*swap)( struct Qntan_HshTbl**, void*elm, void*ptrToDst );