sarif-to-dot: to reduce graph clutter, add option --no-edges-to-scalars

bin/sarif-to-dot

@@ -26,9 +26,15 @@ parser.add_argument('-t', '--typedef-signatures', action="store_true",
                     help='Give every object signature a type and report by types')
 parser.add_argument('-d', '--dot-output', action="store_true",
                     help='Output type table as dot graph.  Implies -t -u')
+parser.add_argument('-n', '--no-edges-to-scalars', action="store_true",
+                    help='Suppress edges to int/bool/string types in dot graph.  Implies -d')
 parser.add_argument('-f', '--fill-structure', action="store_true",
                     help='Fill in missing (optional) entries in sarif input before other steps.')
 args = parser.parse_args()
+
+if args.no_edges_to_scalars:
+    args.dot_output = True
+
 if args.dot_output:
     args.unique_array_signatures = True
     args.typedef_signatures = True
@@ -54,7 +60,7 @@ if args.dot_output:
     for typedef, sig in struct_graph:
         S.write_node(sys.stdout, typedef, sig)
     for typedef, sig in struct_graph:
-        S.write_edges(sys.stdout, typedef, sig)
+        S.write_edges(args, sys.stdout, typedef, sig)
     S.write_footer(sys.stdout)
 
 elif args.typedef_signatures:

sarif_cli/signature.py

@@ -137,7 +137,7 @@ def write_node(fp, typedef, sig):
     """.format(name=typedef, head=typedef, body=label)
     fp.write(node)
 
-def write_edges(fp, typedef, sig):
+def write_edges(args, fp, typedef, sig):
     """ Write edges in dot format.
     """
     if sig in ["string", "int", "bool"]:
@@ -158,10 +158,13 @@ def write_edges(fp, typedef, sig):
             field_name, field_type = field
             label = ""
             dest = str(field_type)
-            edge = """ {src_node}:"{src_port}" -> {dest} [label="{label}"];
-            """.format(src_node=typedef, src_port=field_name, dest=field_type,
-                       label=label)
-            fp.write(edge)
+            if dest in ["String", "Int", "Bool"] and args.no_edges_to_scalars:
+                pass
+            else:
+                edge = """ {src_node}:"{src_port}" -> {dest} [label="{label}"];
+                """.format(src_node=typedef, src_port=field_name, dest=field_type,
+                           label=label)
+                fp.write(edge)
     else:
         raise Exception("unknown signature: " + str(sig))