crashpad_database_util: Don’t create a database unless explicitly asked

client/crash_report_database.h

 // Copyright 2015 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 150 matching lines @@
     //! \brief The operation could not be completed because a concurrent
     //!     operation affecting the report is occurring.
     kBusyError,
   };
 
   virtual ~CrashReportDatabase() {}
 
   //! \brief Initializes a database of crash reports.
   //!
   //! \param[in] path A path to the database to be created or opened.
+  //! \param[in] create If `true`, a database that does not yet exist will be
+  //!     created if possible. If `false`, the database must already exist. Note
+  //!     that for databases implemented as directory structures, existence
+  //!     refers solely to the outermost directory, and that if the outermost
+  //!     directory exists, any inner structure will be created even if \a
+  //!     create is `false`.
   //!
   //! \return A database object on success, `nullptr` on failure with an error
   //!     logged.
-  static scoped_ptr<CrashReportDatabase> Initialize(const base::FilePath& path);
+  static scoped_ptr<CrashReportDatabase> Initialize(const base::FilePath& path,
+                                                    bool create);

[Mark Mentovai, 2015/10/07 18:45:58]

This interface is the one thing I’m not sure about. Users of this interface
probably won’t normally mean to specify create=false.

I was thinking of breaking this into Initialize() and
InitializeWithoutCreating() instead. Any preference?

[scottmg, 2015/10/07 19:16:30]

I agree, I think a separate interface method for normal usage would be clearer. 

Alternatively, an enum class : bool so that it's more obvious at the callsite
that it might be a bad idea to say `false`.

 
   //! \brief Returns the Settings object for this database.
   //!
   //! \return A weak pointer to the Settings object, which is owned by the
   //!     database.
   virtual Settings* GetSettings() = 0;
 
   //! \brief Creates a record of a new crash report.
   //!
   //! Callers can then write the crash report using the file handle provided.
@@ skipping 118 matching lines @@
  protected:
   CrashReportDatabase() {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(CrashReportDatabase);
 };
 
 }  // namespace crashpad
 
 #endif  // CRASHPAD_CLIENT_CRASH_REPORT_DATABASE_H_