Add functions for checking cell reference loops

This commit is contained in:
Mario Hüttel 2019-03-06 20:05:48 +01:00
parent 43fdab4533
commit 3146ca801f

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@ -84,31 +84,117 @@ int gds_tree_check_cell_references(struct gds_library *lib)
}
/**
* @brief This function sets the marker element in the check structure of each cell to zero.
* @param lib Library to work with
* @return 0 if successful; negative if a fault (null pointer, ...) occured.
* @brief Check if list contains a cell
* @param list GList to check. May be a null pointer
* @param cell Cell to check for
* @return 0 if cell is not in list. 1 if cell is in list
*/
static int gds_tree_check_clear_cell_check_marker(struct gds_library *lib)
static int gds_tree_check_list_contains_cell(GList *list, struct gds_cell *cell) {
GList *iter;
for (iter = list; iter != NULL; iter = g_list_next(iter)) {
if ((struct gds_cell *)iter->data == cell)
return 1;
}
return 0;
}
/**
* @brief This function follows down the reference list of a cell and marks each visited subcell and detects loops
* @param cell_to_check The cell to check for reference loops
* @param visited_cells Pointer to list head. May be zero.
* @return 0 if no loops exist; error in processing: <0; loop found: >0
*/
static int gds_tree_check_iterate_ref_and_check(struct gds_cell *cell_to_check, GList **visited_cells)
{
GList *ref_iter;
struct gds_cell_instance *ref;
struct gds_cell *sub_cell;
int res;
if (!cell_to_check)
return -1;
/* Check if this cell is already contained in visited cells. This indicates a loop */
if (gds_tree_check_list_contains_cell(*visited_cells, cell_to_check))
return 1;
/* Add cell to visited cell list */
*visited_cells = g_list_append(*visited_cells, (gpointer)cell_to_check);
/* Mark references and process sub cells */
for (ref_iter = cell_to_check->child_cells; ref_iter != NULL; ref_iter = g_list_next(ref_iter)) {
ref = (struct gds_cell_instance *)ref_iter->data;
if (!ref)
return -1;
sub_cell = ref->cell_ref;
/* If cell is not resolved, ignore. No harm there */
if (!sub_cell)
continue;
res = gds_tree_check_iterate_ref_and_check(sub_cell, visited_cells);
if (res < 0) {
/* Error. return. */
return -3;
} else if (res > 0) {
/* Loop in subcell found. Propagate to top */
return 1;
}
}
/* Remove cell from visted cells */
*visited_cells = g_list_remove(*visited_cells, cell_to_check);
/* No error found in this chain */
return 0;
}
int gds_tree_check_reference_loops(struct gds_library *lib)
{
int res;
int loop_count = 0;
GList *cell_iter;
struct gds_cell *cell;
struct gds_cell *cell_to_check;
GList *visited_cells = NULL;
if (!lib)
return -1;
for (cell_iter = lib->cells; cell_iter != NULL; cell_iter = g_list_next(cell_iter)) {
cell = (struct gds_cell *)cell_iter->data;
cell_to_check = (struct gds_cell *)cell_iter->data;
if (!cell)
/* A broken cell reference will be counted fatal in this case */
if (!cell_to_check)
return -2;
cell->checks._internal.marker = 0;
}
}
/* iterate through references and check if loop exists */
res = gds_tree_check_iterate_ref_and_check(cell_to_check, &visited_cells);
int gds_tree_check_reference_loops(struct gds_library *lib)
{
return 0;
if (res < 0) {
/* Error */
return res;
} else if (res > 0) {
/* Loop found: increment loop count and flag cell */
cell_to_check->checks.affected_by_reference_loop = 1;
loop_count++;
} else if (res == 0) {
/* No error found for this cell */
cell_to_check->checks.affected_by_reference_loop = 0;
}
}
if (visited_cells) {
fprintf(stderr, "Visited cell list should be empty. This is a bug. Please report this.\n");
g_list_free(visited_cells);
}
return loop_count;
}
/** @} */