base: Sync File with google3 implem

Author: Mizux

ortools/base/file.cc

@@ -62,26 +62,30 @@ size_t File::Size() {
 
 bool File::Flush() { return fflush(f_) == 0; }
 
+// Deletes "this" on closing.
 bool File::Close() {
   if (f_ == nullptr) {
     return true;
   }
 
   if (fclose(f_) == 0) {
     f_ = nullptr;
+    delete this;
     return true;
   } else {
     return false;
   }
 }
 
+// Deletes "this" on closing.
 absl::Status File::Close(int flags) {
   if (f_ == nullptr) {
     return absl::Status();
   }
 
   if (fclose(f_) == 0) {
     f_ = nullptr;
+    delete this;
     return absl::Status();
   } else {
     const std::string msg = absl::StrCat("Could not close file '", name_, "'");
@@ -191,27 +195,23 @@ absl::Status GetContents(absl::string_view filename, std::string* output,
   const int64_t size = file->Size();
   if (file->ReadToString(output, size) == size) {
     status.Update(file->Close(flags));
-    delete file;
     return status;
   }
 #if defined(_MSC_VER)
   // On windows, binary files needs to be opened with the "rb" flags.
   file->Close();
-  delete file;
   // Retry in binary mode.
   status = file::Open(filename, "rb", &file, flags);
   if (!status.ok()) return status;
 
   const int64_t b_size = file->Size();
   if (file->ReadToString(output, b_size) == b_size) {
     status.Update(file->Close(flags));
-    delete file;
     return status;
   }
 #endif  // _MSC_VER
 
   file->Close(flags).IgnoreError();  // Even if ReadToString() fails!
-  delete file;
   return absl::Status(absl::StatusCode::kInvalidArgument,
                       absl::StrCat("Could not read from '", filename, "'."));
 }
@@ -233,7 +233,6 @@ absl::Status SetContents(absl::string_view filename, absl::string_view contents,
   if (!status.ok()) return status;
   status = file::WriteString(file, contents, flags);
   status.Update(file->Close(flags));  // Even if WriteString() fails!
-  delete file;
   return status;
 }
 

ortools/util/filelineiter.h

@@ -161,7 +161,6 @@ class FileLines {
   ~FileLines() {
     if (file_ != nullptr) {
       file_->Close(file::Defaults()).IgnoreError();
-      delete file_;
       file_ = nullptr;
     }
   }