2 #include "lfds700_freelist_internal.h"
4 /***** private prototypes *****/
5 static void lfds700_freelist_internal_freelist_validate( struct lfds700_freelist_state *fs, struct lfds700_misc_validation_info *vi, enum lfds700_misc_validity *lfds700_freelist_validity );
11 /****************************************************************************/
12 void lfds700_freelist_query( struct lfds700_freelist_state *fs, enum lfds700_freelist_query query_type, void *query_input, void *query_output )
14 struct lfds700_freelist_element
17 LFDS700_PAL_ASSERT( fs != NULL );
18 // TRD : query_type can be any value in its range
20 LFDS700_MISC_BARRIER_LOAD;
24 case LFDS700_FREELIST_QUERY_SINGLETHREADED_GET_COUNT:
25 LFDS700_PAL_ASSERT( query_input == NULL );
26 LFDS700_PAL_ASSERT( query_output != NULL );
28 *(lfds700_pal_uint_t *) query_output = 0;
30 fe = (struct lfds700_freelist_element *) fs->top[POINTER];
34 ( *(lfds700_pal_uint_t *) query_output )++;
35 fe = (struct lfds700_freelist_element *) fe->next;
39 case LFDS700_FREELIST_QUERY_SINGLETHREADED_VALIDATE:
40 // TRD : query_input can be NULL
41 LFDS700_PAL_ASSERT( query_output != NULL );
43 lfds700_freelist_internal_freelist_validate( fs, (struct lfds700_misc_validation_info *) query_input, (enum lfds700_misc_validity *) query_output );
54 /****************************************************************************/
55 static void lfds700_freelist_internal_freelist_validate( struct lfds700_freelist_state *fs, struct lfds700_misc_validation_info *vi, enum lfds700_misc_validity *lfds700_freelist_validity )
60 struct lfds700_freelist_element
64 LFDS700_PAL_ASSERT( fs != NULL );
65 // TRD : vi can be NULL
66 LFDS700_PAL_ASSERT( lfds700_freelist_validity != NULL );
68 *lfds700_freelist_validity = LFDS700_MISC_VALIDITY_VALID;
70 fe_slow = fe_fast = (struct lfds700_freelist_element *) fs->top[POINTER];
72 /* TRD : first, check for a loop
74 both of which start at the top of the freelist
77 we advance one pointer by one element
80 we exit the loop when both pointers are NULL
81 (have reached the end of the freelist)
85 if we fast pointer 'sees' the slow pointer
86 which means we have a loop
92 fe_slow = fe_slow->next;
95 fe_fast = fe_fast->next;
98 fe_fast = fe_fast->next;
100 while( fe_slow != NULL and fe_fast != fe_slow );
102 if( fe_fast != NULL and fe_slow != NULL and fe_fast == fe_slow )
103 *lfds700_freelist_validity = LFDS700_MISC_VALIDITY_INVALID_LOOP;
105 /* TRD : now check for expected number of elements
106 vi can be NULL, in which case we do not check
107 we know we don't have a loop from our earlier check
110 if( *lfds700_freelist_validity == LFDS700_MISC_VALIDITY_VALID and vi != NULL )
112 lfds700_freelist_query( fs, LFDS700_FREELIST_QUERY_SINGLETHREADED_GET_COUNT, NULL, (void *) &number_elements );
114 if( number_elements < vi->min_elements )
115 *lfds700_freelist_validity = LFDS700_MISC_VALIDITY_INVALID_MISSING_ELEMENTS;
117 if( number_elements > vi->max_elements )
118 *lfds700_freelist_validity = LFDS700_MISC_VALIDITY_INVALID_ADDITIONAL_ELEMENTS;