Use a callable type for ScopedFILE in settings_writer.cc

Newer glibc have an attribute((nonnull(1))) on fclose. Attributes aren't
part of the language, so decltype(fclose) lose the attribute. It seems
this causes std::unique_ptr<FILE, decltype(fclose)> to trip
-Wignored-attributes in GCC.

This is a bit aggressive of a warning, but work around this with a
custom deleter, which makes the unique_ptr object smaller anyway.
(Though the compiler can, I hope, dissolve all of this anyway.)

Fixed: 642
Change-Id: I9a0206a8c5675f856e80c5266c90be42d66a5606
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/62465
Auto-Submit: David Benjamin <davidben@google.com>
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
(cherry picked from commit e4f60679caa293c047be69f57fc48b46c7452327)

crypto/test/test_util.h

@@ -76,10 +76,10 @@ bssl::UniquePtr<X509> CertFromPEM(const char *pem);
 // unique_ptr will automatically call fclose on the file descriptior when the
 // variable goes out of scope, so we need to specify BIO_NOCLOSE close flags
 // to avoid a double-free condition.
-struct fclose_deleter {
+struct FileCloser {
   void operator()(FILE *f) const { fclose(f); }
 };
 
-using TempFILE = std::unique_ptr<FILE, fclose_deleter>;
+using TempFILE = std::unique_ptr<FILE, FileCloser>;
 
 #endif  // OPENSSL_HEADER_CRYPTO_TEST_TEST_UTIL_H

ssl/ssl_test.cc

@@ -11951,11 +11951,11 @@ TEST(SSLTest, SSLFileTests) {
   GTEST_SKIP();
 #endif
 
-  struct fclose_deleter {
+  struct FileCloser {
     void operator()(FILE *f) const { fclose(f); }
   };
 
-  using ScopedFILE = std::unique_ptr<FILE, fclose_deleter>;
+  using ScopedFILE = std::unique_ptr<FILE, FileCloser>;
 
 #if defined(OPENSSL_WINDOWS)
   char rsa_pem_filename[L_tmpnam];

ssl/test/settings_writer.cc

@@ -75,11 +75,10 @@ bool SettingsWriter::Commit() {
   }
   bssl::UniquePtr<uint8_t> free_settings(settings);
 
-  struct fclose_deleter {
+  struct FileCloser {
     void operator()(FILE *f) const { fclose(f); }
   };
-
-  using ScopedFILE = std::unique_ptr<FILE, fclose_deleter>;
+  using ScopedFILE = std::unique_ptr<FILE, FileCloser>;
   ScopedFILE file(fopen(path_.c_str(), "w"));
   if (!file) {
     return false;

ssl/test/ssl_transfer.cc

@@ -22,11 +22,11 @@ static bool WriteData(std::string prefix, const uint8_t *input, size_t len) {
     return true;
   }
 
-  struct fclose_deleter {
+  struct FileCloser {
     void operator()(FILE *f) const { fclose(f); }
   };
 
-  using ScopedFILE = std::unique_ptr<FILE, fclose_deleter>;
+  using ScopedFILE = std::unique_ptr<FILE, FileCloser>;
   std::string path = prefix + "-" + std::to_string(rand());
   ScopedFILE file(fopen(path.c_str(), "w"));
   if (!file) {