Raise exception on missing unused input_map keys with C API enabled.

Without this change, the C++ ImportGraphDef API returns unused
input_map keys (which are plumbed through to the C API as
well). However, the Python import_graph_def API requires slightly
different semantics: it throws an error for unused input_map keys that
are missing from the GraphDef.

This change modifies the C and C++ APIs to limit the returned keys to
those missing from the GraphDef, and plumbs this through to the C
API-enabled import_graph_def implementation.

Note that this is a change to the existing C API. Luckily the modified
method hasn't been released yet, so it's ok to change it.

PiperOrigin-RevId: 178783957

1 files changed, 20 insertions, 17 deletions

diff --git a/tensorflow/c/c_api.cc b/tensorflow/c/c_api.cc
index 13253ced49..6f5abd074c 100644
--- a/tensorflow/c/c_api.cc
+++ b/tensorflow/c/c_api.cc
@@ -1917,12 +1917,12 @@ void TF_ImportGraphDefResultsReturnOperations(TF_ImportGraphDefResults* results,
   *opers = results->return_nodes.data();
 }
 
-void TF_ImportGraphDefResultsUnusedInputMappings(
-    TF_ImportGraphDefResults* results, int* num_unused_input_mappings,
+void TF_ImportGraphDefResultsMissingUnusedInputMappings(
+    TF_ImportGraphDefResults* results, int* num_missing_unused_input_mappings,
     const char*** src_names, int** src_indexes) {
-  *num_unused_input_mappings = results->unused_key_names.size();
-  *src_names = results->unused_key_names.data();
-  *src_indexes = results->unused_key_indexes.data();
+  *num_missing_unused_input_mappings = results->missing_unused_key_names.size();
+  *src_names = results->missing_unused_key_names.data();
+  *src_indexes = results->missing_unused_key_indexes.data();
 }
 
 void TF_DeleteImportGraphDefResults(TF_ImportGraphDefResults* results) {
@@ -1962,18 +1962,21 @@ static void GraphImportGraphDefLocked(TF_Graph* graph, const GraphDef& def,
     tf_results->return_nodes[i] = ToOperation(results.return_nodes[i]);
   }
 
-  // Populate unused map keys
-  DCHECK(tf_results->unused_key_names.empty());
-  DCHECK(tf_results->unused_key_indexes.empty());
-  DCHECK(tf_results->unused_key_names_data.empty());
-  tf_results->unused_key_names.resize(results.unused_input_map_keys.size());
-  tf_results->unused_key_indexes.resize(results.unused_input_map_keys.size());
-  for (int i = 0; i < results.unused_input_map_keys.size(); ++i) {
-    TensorId id = results.unused_input_map_keys[i];
-    tf_results->unused_key_names_data.push_back(id.first.ToString());
-    tf_results->unused_key_names[i] =
-        tf_results->unused_key_names_data.back().c_str();
-    tf_results->unused_key_indexes[i] = id.second;
+  // Populate missing unused map keys
+  DCHECK(tf_results->missing_unused_key_names.empty());
+  DCHECK(tf_results->missing_unused_key_indexes.empty());
+  DCHECK(tf_results->missing_unused_key_names_data.empty());
+
+  size_t size = results.missing_unused_input_map_keys.size();
+  tf_results->missing_unused_key_names.resize(size);
+  tf_results->missing_unused_key_indexes.resize(size);
+
+  for (int i = 0; i < size; ++i) {
+    TensorId id = results.missing_unused_input_map_keys[i];
+    tf_results->missing_unused_key_names_data.push_back(id.first.ToString());
+    tf_results->missing_unused_key_names[i] =
+        tf_results->missing_unused_key_names_data.back().c_str();
+    tf_results->missing_unused_key_indexes[i] = id.second;
   }
 }