This patch introduces the concepts of the "crash data store" and "crash
event files." The "crash data store" is a data store containing
information about crashes. Data is added to this store directly through
a JavaScript API or by the presence of "crash event files." A "crash
event file" is simply an individual file containing information about
a crash event. These files are periodically scanned and their contents
are merged into the store.
Currently, no specific event files types are defined. This patch merely
begins to implement the infrastructure for dealing with them. Support
for specific crash events will be added in subsequent patches.
The tree doesn't have a robust and reusable API for interfacing with
crash data. This patch is the start of a new API.
In this patch, the CrashManager type is introduced. It has APIs for
retrieving the lists of files related to crash dumps. In subsequent
patches, I will convert existing code in the tree that does similar
things to the new API. I will also build the events/timeline API onto
this type.
I made CrashManager generic because I hate, hate, hate singletons and
global variables. Allowing it to be instantiated multiple times with
different options (instead of say binding a global instance to ProfD)
makes the testing story much, much nicer. That is reason enough, IMO. In
a subsequent patch, I'll add an XPCOM service that instantiates the
"global" instance of CrashManager with the appropriate options.
It was tempting to add this code into the existing CrashReports.jsm.
However, this file does not import cleanly in xpcshell tests and I
didn't want to bloat scope to include fixing that file... yet.
CrashReports.jsm is using synchronous I/O. So, depending on how
adventerous I feel, I may replace consumers of CrashReports.jsm with the
new CrashManager.jsm, remove CrashReports.jsm, and eliminate another
source of synchronous I/O in the tree.
