Improve error handling of the transport security state generator.

net/tools/transport_security_state_generator/preloaded_state_generator.cc

Index: net/tools/transport_security_state_generator/preloaded_state_generator.cc
diff --git a/net/tools/transport_security_state_generator/preloaded_state_generator.cc b/net/tools/transport_security_state_generator/preloaded_state_generator.cc
index 64e89890ac76506ff85f910a8bdf7febca645b74..b1bcabbe05fc578e22e8ccd7bceb652a97bd11e8 100644
--- a/net/tools/transport_security_state_generator/preloaded_state_generator.cc
+++ b/net/tools/transport_security_state_generator/preloaded_state_generator.cc
@@ -4,10 +4,9 @@
 
 #include "net/tools/transport_security_state_generator/preloaded_state_generator.h"
 
-#include <iostream>
-
 #include <string>
 
+#include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "net/tools/transport_security_state_generator/cert_util.h"
@@ -133,8 +132,7 @@ std::string PreloadedStateGenerator::Generate(
     const std::string& preload_template,
     const TransportSecurityStateEntries& entries,
     const DomainIDList& domain_ids,
-    const Pinsets& pinsets,
-    bool verbose) {
+    const Pinsets& pinsets) {
   std::string output = preload_template;
 
   NameIDMap domain_ids_map;
@@ -161,32 +159,28 @@ std::string PreloadedStateGenerator::Generate(
   TrieWriter writer(table, domain_ids_map, expect_ct_report_uri_map,
                     expect_staple_report_uri_map, pinsets_map,
                     &huffman_builder);
-  writer.WriteEntries(entries);
-  uint32_t initial_length = writer.position();
+  uint32_t root_position;
+  if (!writer.WriteEntries(entries, &root_position)) {
+    return std::string();
+  }
 
   HuffmanRepresentationTable optimal_table = huffman_builder.ToTable();
   TrieWriter new_writer(optimal_table, domain_ids_map, expect_ct_report_uri_map,
                         expect_staple_report_uri_map, pinsets_map, nullptr);
 
-  uint32_t root_position = new_writer.WriteEntries(entries);
-  uint32_t new_length = new_writer.position();
+  if (!new_writer.WriteEntries(entries, &root_position)) {
+    return std::string();
+  }
 
+  uint32_t new_length = new_writer.position();
   std::vector<uint8_t> huffman_tree = huffman_builder.ToVector();
-
   new_writer.Flush();
 
   ReplaceTag("HUFFMAN_TREE", FormatVectorAsArray(huffman_tree), &output);
   ReplaceTag("HSTS_TRIE", FormatVectorAsArray(new_writer.bytes()), &output);
 
-  ReplaceTag("HSTS_TRIE_BITS", std::to_string(new_length), &output);
-  ReplaceTag("HSTS_TRIE_ROOT", std::to_string(root_position), &output);
-
-  if (verbose) {
-    std::cout << "Saved " << std::to_string(initial_length - new_length)
-              << " bits by using accurate Huffman counts." << std::endl;
-    std::cout << "Bit length " << std::to_string(new_length) << std::endl;
-    std::cout << "Root position " << std::to_string(root_position) << std::endl;
-  }
+  ReplaceTag("HSTS_TRIE_BITS", base::SizeTToString(new_length), &output);
+  ReplaceTag("HSTS_TRIE_ROOT", base::SizeTToString(root_position), &output);
 
   return output;
 }
@@ -275,6 +269,11 @@ void PreloadedStateGenerator::ProcessExpectCTURIs(
     }
   }
 
+  output.append(kIndent);
+  output.append(kIndent);
+  output.append("NULL,");
+  output.append(kNewLine);
+
   output.append("}");
   ReplaceTag("EXPECT_CT_REPORT_URIS", output, tpl);
 }
@@ -302,6 +301,11 @@ void PreloadedStateGenerator::ProcessExpectStapleURIs(
     }
   }
 
+  output.append(kIndent);
+  output.append(kIndent);
+  output.append("NULL,");
+  output.append(kNewLine);
+
   output.append("}");
   ReplaceTag("EXPECT_STAPLE_REPORT_URIS", output, tpl);
 }