Add support to the gpma to delete an item at a particular index. Addresses #690.

git-svn-id: file:///svn/tokudb@3441 c7de825b-a66e-492c-adef-691d508d4ae1

newbrt/gpma.c

@@ -512,6 +512,14 @@ int toku_smooth_deleted_region (GPMA pma, u_int32_t minidx, u_int32_t maxidx, gp
     }
 }
 
+int toku_gpma_delete_at_index (GPMA pma, u_int32_t index,
+			       gpma_renumber_callback_t renumberf,
+			       void *extra_for_renumberf) {
+    toku_gpma_clear_at_index(pma, index);
+    return toku_smooth_deleted_region(pma, index, index, renumberf, extra_for_renumberf);
+}
+
+
 int toku_gpma_delete_bessel (GPMA pma,
 			     gpma_besselfun_t besself,           void*extra_for_besself,
 			     gpma_delete_callback_t deletef,     void*extra_for_deletef,  // for each deleted item, let the caller know

newbrt/gpma.h

@@ -52,6 +52,12 @@ int toku_gpma_insert_bessel (GPMA pma,
 			     u_int32_t *indexp // Where did the item get stored?
 			     );			     
 
+// Delete a particular index, and rebalance the tree.
+int toku_gpma_delete_at_index (GPMA pma, u_int32_t index,
+			       gpma_renumber_callback_t renumberf,
+			       void *extra_for_renumberf);
+			       
+
 // Delete anything for which the besselfun is zero.  The besselfun must be monotonically increasing compared to the comparison function.
 // That is, if two othings compare to be < then their besselfun's must yield <=, and if the compare to be = their besselfuns must be =, and if they are > then their besselfuns must be >=
 // Note the delete_callback would be responsible for calling free on the object.
@@ -97,6 +103,7 @@ int toku_gpma_get_from_index (GPMA, u_int32_t idx, u_int32_t *len, void **data);
 
 // Whatever is in the slot gets overwritten.  Watch out that you free the thing before overwriting it.
 void toku_gpma_set_at_index (GPMA, u_int32_t idx, u_int32_t len, void*data);
+// Clears the item at a particular index without rebalancing the PMA.
 void toku_gpma_clear_at_index (GPMA, u_int32_t idx);
 
 int toku_gpma_move_inside_pma_by_renumbering (GPMA,

newbrt/test-gpma-blackbox.c

@@ -340,6 +340,53 @@ void test_delete (void) {
     test_delete_n(300);
 }
 
+void test_delete_at (void) {
+    GPMA pma;
+    int r = toku_gpma_create(&pma, 0);
+    assert(r==0);
+    int i, j;
+    int N=20;
+    char *strings[N];
+    for (i=0; i<N; i++) {
+	char str[6];
+	snprintf(str, 6, "%05d", i);
+	strings[i]=strdup(str);
+	r = toku_gpma_insert(pma, 6, strings[i], compare_strings, 0, rcall_ok, strings[i], 0);
+	assert(r==0);
+	//printf("insert, N=%d\n", toku_gpma_index_limit(pma));
+    }
+    u_int32_t max_limit = toku_gpma_index_limit(pma);
+    u_int32_t min_limit = max_limit;
+    u_int32_t prev_limit = max_limit;
+    u_int32_t resultlen, idx;
+    void *resultdata;
+    for (j=0; j<N; j++) {
+	r = toku_gpma_lookup_item(pma, 6, strings[j], compare_strings, 0, &resultlen, &resultdata, &idx);
+	assert(r==0);
+	assert(resultlen==6);
+	assert(0==strcmp(resultdata, strings[j]));
+	r = toku_gpma_delete_at_index(pma, idx, 0, 0);
+	assert(r==0);
+	u_int32_t this_limit = toku_gpma_index_limit(pma);
+	if (this_limit<min_limit) min_limit=this_limit;
+	assert(this_limit<=prev_limit);
+	prev_limit=this_limit;
+	//printf("delete, N=%d\n", this_limit);
+
+	for (i=0; i<=j; i++) {
+	    r = toku_gpma_lookup_item(pma, 6, strings[i], compare_strings, 0, &resultlen, &resultdata, &idx);
+	    assert(r==DB_NOTFOUND);
+	}
+	for (i=j+1; i<N; i++) {
+	    r = toku_gpma_lookup_item(pma, 6, strings[i], compare_strings, 0, &resultlen, &resultdata, &idx);
+	    assert(r==0);
+	    assert(resultlen==6);
+	    assert(0==strcmp(resultdata, strings[i]));
+	}
+    }
+    assert(min_limit<max_limit);
+}
+
 static int compare_this_string (u_int32_t dlen, void *dval, void *extra) {
     assert(dlen==1+strlen(dval));
     return strcmp(dval, extra);
@@ -393,6 +440,7 @@ int main (int argc, const char *argv[]) {
     test_insert_A();
     test_split();
     test_delete();
+    test_delete_at();
     test_bes();
     toku_malloc_cleanup();
     return 0;