37 Commits

Author SHA1 Message Date
Arthur Wang
981d4189aa Replace std::unique_ptr<T> with HeapArray
Bug: crashpad: 326459659,326458942,326459376,326459390,326459417,326458979,326459333,326459016,326458338,326458738,326459156,326459512,326458694
Change-Id: I04724530cbef50a8d3c18f306d16c0bbf3b0815b
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/5512394
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Arthur Wang <wuwang@chromium.org>
2024-05-09 22:16:58 +00:00
Lei Zhang
1675ce7c58 Add missing base/check.h includes
Do not rely on base/logging.h to provide it.

Change-Id: I8b7d733bcf66abe9b46eabd3703b7ed549d02db7
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/5007844
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Mark Mentovai <mark@chromium.org>
2023-11-06 22:00:17 +00:00
Mark Mentovai
6278690abe Update copyright boilerplate, 2022 edition (Crashpad)
sed -i '' -E -e 's/Copyright (.+) The Crashpad Authors\. All rights reserved\.$/Copyright \1 The Crashpad Authors/' $(git grep -El 'Copyright (.+) The Crashpad Authors\. All rights reserved\.$')

Bug: chromium:1098010
Change-Id: I8d6138469ddbe3d281a5d83f64cf918ec2491611
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/3878262
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
Commit-Queue: Mark Mentovai <mark@chromium.org>
2022-09-06 23:54:07 +00:00
Daniel Cheng
0affe61689 Migrate base::{size,empty,data} to STL equivalents in crashpad.
Bug: chromium:1299695
Change-Id: I95187a425b08c96430c659f843c379d506972f0f
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/3496462
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Mark Mentovai <mark@chromium.org>
2022-03-01 12:06:49 +00:00
Peter Boström
1aa478d161 Remove DISALLOW_* macros in crashpad
This change was partially scripted and partially done manually with vim
regex + manually placing the deleted constructors.

The script change looked for destructors in the public: section of a
class, if that existed the deleted constructors would go before the
destructor.

For manual placement I looked for any constructor in the public: section
of the corresponding class. If there wasn't one, then it would ideally
have gone as the first entry except below enums, classes and typedefs.
This may not have been perfect, but is hopefully good enough. Fingers
crossed.

#include "base/macros.h" is removed from files that don't use
ignore_result, which is the only other thing defined in base/macros.h.

Bug: chromium:1010217
Change-Id: I099526255a40b1ac1264904b4ece2f3f503c9418
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/3171034
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Peter Boström <pbos@chromium.org>
2021-09-21 15:09:44 +00:00
Justin Cohen
ce378c4293 Fix some chromium roll errors and warnings.
Remove unneeded base/strings/stringprintf.h includes.
ARCH_CPU_X86_64 macro is used without including build/build_config.h
Missing base/check.h

Change-Id: Ib7864ab7b30ef8fc37649783f7b90b618d0d6a0b
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/2920552
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Justin Cohen <justincohen@chromium.org>
2021-06-02 22:02:42 +00:00
Lei Zhang
d8f60c8112 Swap from base/stl_util.h to cxx17_backports.h.
Chromium moved base::size() to base/cxx17_backports.h, so do the same in
mini_chromium and update the users in Crashpad.

Roll mini_chromium to 2f06f83f to make the new base header available.

Bug: chromium:1210983
Change-Id: Ie3dc4c189dcdfcac030b95fe285f94abb29a27bf
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/2917779
Commit-Queue: Lei Zhang <thestig@chromium.org>
Commit-Queue: Mark Mentovai <mark@chromium.org>
Reviewed-by: Mark Mentovai <mark@chromium.org>
2021-05-25 21:44:52 +00:00
Mark Mentovai
e621aaa132 Make “gn check” pass
Change-Id: Ia7a215e1a2d0a3b1868b00c5d47b46ef8a675cdc
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/2144917
Reviewed-by: Justin Cohen <justincohen@chromium.org>
Reviewed-by: Joshua Peraza <jperaza@chromium.org>
Commit-Queue: Mark Mentovai <mark@chromium.org>
2020-04-13 18:29:42 +00:00
Mark Mentovai
cc166d71f4 Use base::size where appropriate, and ArraySize elsewhere
This is a follow-up to c8a016b99d97, following the post-landing
discussion at
https://chromium-review.googlesource.com/c/crashpad/crashpad/+/1393921/5#message-2058541d8c4505d20a990ab7734cd758e437a5f7

base::size, and std::size that will eventually replace it when C++17 is
assured, does not allow the size of non-static data members to be taken
in constant expression context. The remaining uses of ArraySize are in:

minidump/minidump_exception_writer.cc (×1)
minidump/minidump_system_info_writer.cc (×2, also uses base::size)
snapshot/cpu_context.cc (×4, also uses base::size)
util/misc/arraysize_test.cc (×10, of course)

The first of these occurs when initializing a constexpr variable. All
others are in expressions used with static_assert.

Includes:
Update mini_chromium to 737433ebade4d446643c6c07daae02a67e8deccao

f701716d9546 Add Windows ARM64 build target to mini_chromium
87a95a3d6ac2 Remove the arraysize macro
1f7255ead1f7 Placate MSVC in areas of base::size usage
737433ebade4 Add cast

Bug: chromium:837308
Change-Id: I6a5162654461b1bdd9b7b6864d0d71a734bcde19
Reviewed-on: https://chromium-review.googlesource.com/c/1396108
Commit-Queue: Mark Mentovai <mark@chromium.org>
Reviewed-by: Mark Mentovai <mark@chromium.org>
2019-01-04 22:42:57 +00:00
Avi Drissman
c8a016b99d Remove base's arraysize from Crashpad.
BUG=837308
R=mark@chromium.org

Change-Id: Ibecbfc7bc2d61ee54bc1114e4b20978adbc77db2
Reviewed-on: https://chromium-review.googlesource.com/c/1393921
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Avi Drissman <avi@chromium.org>
2019-01-03 19:44:15 +00:00
Mark Mentovai
e04194afd9 win: Wrap TerminateProcess() to accept cdecl patches on x86
TerminateProcess(), like most of the Windows API, is declared WINAPI,
which is __stdcall on 32-bit x86. That means that the callee,
TerminateProcess() itself, is responsible for cleaning up parameters on
the stack on return. In https://crashpad.chromium.org/bug/179, crashes
in ExceptionHandlerServer::OnNonCrashDumpEvent() were observed in ways
that make it evident that TerminateProcess() has been patched with a
__cdecl routine. The crucial difference between __stdcall and __cdecl is
that the caller is responsible for stack parameter cleanup in __cdecl.
The mismatch means that nobody cleans parameters from the stack, and the
stack pointer has an unexpected value, which in the case of the Crashpad
handler crash, results in TerminateProcess()’s second argument
erroneously being used as the lock address in the call to
ReleaseSRWLockExclusive() or LeaveCriticalSection().

As a workaround, on 32-bit x86, call through SafeTerminateProcess(), a
custom assembly routine that’s compatible with either __stdcall or
__cdecl implementations of TerminateProcess() by not trusting the value
of the stack pointer on return from that function. Instead, the stack
pointer is restored directly from the frame pointer.

Bug: crashpad:179
Test: crashpad_util_test SafeTerminateProcess.*, others
Change-Id: If9508f4eb7631020ea69ddbbe4a22eb335cdb325
Reviewed-on: https://chromium-review.googlesource.com/481180
Reviewed-by: Scott Graham <scottmg@chromium.org>
2017-04-19 17:45:32 +00:00
Mark Mentovai
00b6442752 Make file_io reads more rational and predictable
ReadFile() attempted to continue reading after a short read. In most
cases, this is fine. However, ReadFile() would keep trying to fill a
partially-filled buffer until experiencing a 0-length read(), signaling
end-of-file. For certain weird file descriptors like terminal input, EOF
is an ephemeral condition, and attempting to read beyond EOF doesn’t
actually return 0 (EOF) provided that they remain open, it will block
waiting for more input. Consequently, ReadFile() and anything based on
ReadFile() had an undocumented and quirky interface, which was that any
short read that it returned (not an underlying short read) actually
indicated EOF.

This facet of ReadFile() was unexpected, so it’s being removed. The new
behavior is that ReadFile() will return an underlying short read. The
behavior of FileReaderInterface::Read() is updated in accordance with
this change.

Upon experiencing a short read, the caller can determine the best
action. Most callers were already prepared for this behavior. Outside of
util/file, only crashpad_database_util properly implemented EOF
detection according to previous semantics, and adapting it to new
semantics is trivial.

Callers who require an exact-length read can use the new
ReadFileExactly(), or the newly renamed LoggingReadFileExactly() or
CheckedReadFileExactly(). These functions will retry following a short
read. The renamed functions were previously called LoggingReadFile() and
CheckedReadFile(), but those names implied that they were simply
wrapping ReadFile(), which is not the case. They wrapped ReadFile() and
further, insisted on a full read. Since ReadFile()’s semantics are now
changing but these functions’ are not, they’re now even more distinct
from ReadFile(), and must be renamed to avoid confusion.

Test: *
Change-Id: I06b77e0d6ad8719bd2eb67dab93a8740542dd908
Reviewed-on: https://chromium-review.googlesource.com/456676
Reviewed-by: Robert Sesek <rsesek@chromium.org>
2017-03-16 20:07:43 +00:00
Scott Graham
76ef9b5c2b win: Address failure-to-start-handler case for async startup
Second follow up to https://chromium-review.googlesource.com/c/400015/

The ideal would be that if we fail to start the handler, then we don't
end up passing through our unhandled exception filter at all.

In the case of the non-initial client (i.e. renderers) we can do this by
not setting our UnhandledExceptionFilter until after we know we've
connected successfully (because those connections are synchronous from
its point of view). We also change WaitForNamedPipe in the connection
message to block forever, so as long as the precreated pipe exists,
they'll wait to connect. After the initial client has passed the server
side of that pipe to the handler, the handler has the only handle to it.
So, if the handler has disappeared for whatever reason, pipe-connecting
clients will fail with FILE_NOT_FOUND, and will not stick around in the
connection loop. This means non-initial clients do not need additional
logic to avoid getting stuck in our UnhandledExceptionFilter.

For the initial client, it would be ideal to avoid passing through our
UEF too, but none of the 3 options are great:
1. Block until we find out if we started, and then install the filter.
   We don't want to do that, because we don't want to wait.
2. Restore the old filter if it turns out we failed to start. We can't
   do that because Chrome disables ::SetUnhandledExceptionFilter()
   immediately after StartHandler/SetHandlerIPCPipe returns.
3. Don't install our filter until we've successfully started. We don't
   want to do that because we'd miss early crashes, negating the benefit
   of deferred startup.

So, we do need to pass through our UnhandledExceptionFilter. I don't
want more Win32 API calls during the vulnerable filter function. So, at
any point during async startup where there's a failure, set a global
atomic that allows the filter function to abort without trying to signal
a handler that's known to not exist.

One further improvement we might want to look at is unexpected
termination of the handler (as opposed to a failure to start) which
would still result in a useless Sleep(60s). This isn't new behaviour,
but now we have a clear thing to do if we detect the handler is gone.

(Also a missing DWORD/size_t cast for the _x64 bots.)

R=mark@chromium.org
BUG=chromium:567850,chromium:656800

Change-Id: I5be831ca39bd8b2e5c962b9647c8bd469e2be878
Reviewed-on: https://chromium-review.googlesource.com/400985
Reviewed-by: Mark Mentovai <mark@chromium.org>
2016-11-02 21:39:52 +00:00
Scott Graham
2d87606bb5 win: Start crashpad_handler by inheriting connection data to it
Previously, StartHandler() launched the handler process, then connected
over a pipe to register for crash handling. Instead, the initial client
can create and inherit handles to the handler and pass those handle
values and other data (addresses, etc.) on the command line.

This should improve startup time as there's no need to synchronize with
the process at startup, and allows avoiding a call to CreateProcess()
directly in StartHandler(), which is important for registration for
crash reporting from DllMain().

Incidentally adds new utility functions for string/number conversion and
string splitting.

Note: API change; UseHandler() is removed for all platforms.

BUG=chromium:567850,chromium:656800

Change-Id: I1602724183cb107f805f109674c53e95841b24fd
Reviewed-on: https://chromium-review.googlesource.com/400015
Reviewed-by: Mark Mentovai <mark@chromium.org>
2016-10-21 20:35:58 +00:00
Mark Mentovai
6d2d31d2d1 Use base/macros.h instead of base/basictypes.h
This was done in Chromium’s local copy of Crashpad in 562827afb599. This
change is similar to that one, except more care was taken to avoid
including headers from a .cc or _test.cc when already included by the
associated .h. Rather than using <stddef.h> for size_t, Crashpad has
always used <sys/types.h>, so that’s used here as well.

This updates mini_chromium to 8a2363f486e3a0dc562a68884832d06d28d38dcc,
which removes base/basictypes.h.

e128dcf10122 Remove base/move.h; use std::move() instead of Pass()
8a2363f486e3 Move basictypes.h to macros.h

R=avi@chromium.org

Review URL: https://codereview.chromium.org/1566713002 .
2016-01-06 12:22:50 -05:00
Mark Mentovai
583d1dc3ef Provide std::move() in compat instead of using crashpad::move()
This more-natural spelling doesn’t require Crashpad developers to have
to remember anything special when writing code in Crashpad. It’s easier
to grep for and it’s easier to remove the “compat” part when pre-C++11
libraries are no longer relevant.

R=scottmg@chromium.org

Review URL: https://codereview.chromium.org/1513573005 .
2015-12-09 17:36:32 -05:00
Scott Graham
b9e732d318 win: Fix a few sign mismatch warnings in crashpad.
BUG=chromium:567877
R=mark@chromium.org, scottmg@chromium.org

Review URL: https://codereview.chromium.org/1503403003 .
2015-12-08 14:21:29 -08:00
Dana Jansens
6bebb10829 Replace use of .Pass() with crashpad::move().
Since C++11 library support isn't available everywhere crashpad is
compiled, add our own move() method in the crashpad namespace to replace
std::move() for now. Replace uses of .Pass() with this method.

R=mark@chromium.org, scottmg@chromium.org
BUG=chromium:557422

Review URL: https://codereview.chromium.org/1483073004 .
2015-11-30 14:20:54 -08:00
Scott Graham
74e69ed555 win: Avoid some more clang complaints
R=mark@chromium.org
BUG=chromium:82385

Review URL: https://codereview.chromium.org/1463633002 .
2015-11-19 15:09:59 -08:00
Mark Mentovai
4f09b58d1f Add RandomString() and its test, and use it everywhere it makes sense
This unifies several things that used a 16-character random string, and
a few other users of random identifiers where it also made sense to use
a 16-character random string.

TEST=crashpad_util_test RandomString.RandomString
R=scottmg@chromium.org

Review URL: https://codereview.chromium.org/1451793002 .
2015-11-16 13:39:01 -05:00
Scott Graham
e75e8c800f win: Lower integrity level of connection pipe
This is necessary to be able to connect to crashpad_handler from a
Chrome renderer.

R=jschuh@chromium.org, mark@chromium.org
BUG=chromium:546288

Review URL: https://codereview.chromium.org/1405093013 .
2015-11-06 10:43:39 -08:00
Mark Mentovai
2eeaa3ac54 win: Add HandleToInt() and IntToHandle()
This consolidates all of the twisted casts and comments that discuss how
HANDLEs are really only 32 bits wide even in 64-bit processes on 64-bit
operating systems into a single location.

R=scottmg@chromium.org

Review URL: https://codereview.chromium.org/1422503015 .
2015-11-05 14:00:26 -05:00
Mark Mentovai
3e988865ad win: crashpad_handler should create its own pipe name in ephemeral mode
Allowing the client to create its own pipe name string caused a race
between client and server. Instead, in this mode, the server now creates
the pipe name along with a pipe, and returns it to its client via a
--handshake-handle. This guarantees that by the time the client gets the
pipe name, the server has already created it.

Ephemeral mode is now implied by --handshake-handle. The --persistent
option is gone. --persistent mode is enabled when using --pipe-name.

BUG=crashpad:69
R=scottmg@chromium.org

Review URL: https://codereview.chromium.org/1432563003 .
2015-11-03 19:26:18 -05:00
Mark Mentovai
740c668e87 win: Implement CrashpadClient::StartHandler()
BUG=crashpad:69
R=scottmg@chromium.org

Review URL: https://codereview.chromium.org/1428803006 .
2015-11-02 13:59:36 -05:00
Mark Mentovai
06ad194571 win: Construct ExceptionHandlerServer() with its pipe argument (again)
This re-lands 9d03d54d0ba1, which was partially un-done by an apparent
bad rebase leading up to fc7d8b3a27e1.

Review URL: https://codereview.chromium.org/1424213005 .
2015-10-29 18:19:37 -04:00
Mark Mentovai
fc7d8b3a27 mac: Make crashpad_handler get its receive right from its client
Previously, crashpad_handler made its own receive right, and transferred
a corresponding send right to its client. There are two advantages to
making the receive right in the client:

 - It is possible to monitor the receive right for a port-destroyed
   notificaiton in the client, allowing the handler to be restarted if
   it dies.
 - For the future run-from-launchd mode (bug crashpad:25), the handler
   will obtain its receive right from the bootstrap server instead of
   making its own. Having the handler get its receive right from
   different sources allows more code to be shared than if it were to
   sometimes get a receive right and sometimes make a receive right and
   transfer a send right.

This includes a restructuring in crashpad_client_mac.cc that will make
it easier to give it an option to restart crashpad_handler if it dies.
The handler starting logic should all behave the same as before.

BUG=crashpad:68
R=rsesek@chromium.org

Review URL: https://codereview.chromium.org/1409073013 .
2015-10-29 18:09:03 -04:00
Mark Mentovai
9d03d54d0b win: Construct ExceptionHandlerServer() with its pipe argument
This allows better code sharing in crashpad_handler’s main(). It doesn’t
look like much of an improvement now, but a separate change will cause
the Mac ExceptionHandlerServer() to be constructed with an argument. It
will be beneficial for Mac and Windows to be able to share the Run()
call.

R=scottmg@chromium.org

Review URL: https://codereview.chromium.org/1402333004 .
2015-10-29 15:12:23 -04:00
Scott Graham
4b780ba040 Tidy up to enable C4800 on Windows
Fixes two incorrect usages of ssize_t/off_t being implicitly converted
to bool. As such, I think it's worth the cost of the additional !! on
BOOL returning Win32 functions.

R=mark@chromium.org

Review URL: https://codereview.chromium.org/1408123006 .
2015-10-22 14:32:13 -07:00
Mark Mentovai
d075a9eb2e win: Add and use GET_FUNCTION() and GET_FUNCTION_REQUIRED()
These wrap the GetProcAddress(LoadLibrary(), …) idiom into macros that
are much less wordy.

TEST=crashpad_util_test GetFunction.GetFunction and all others
R=scottmg@chromium.org

Review URL: https://codereview.chromium.org/1405323003 .
2015-10-19 14:32:07 -04:00
Scott Graham
4893a9b76d win: Capture some CRITICAL_SECTION debugging data
Capture the memory for the loader lock (can be inspected by !cs), as
well as all locks that were created with .DebugInfo which can be viewed
with !locks.

e.g.

0:000> !cs ntdll!LdrpLoaderLock
-----------------------------------------
Critical section   = 0x778d6410 (ntdll!LdrpLoaderLock+0x0)
DebugInfo          = 0x778d6b6c
NOT LOCKED
LockSemaphore      = 0x0
SpinCount          = 0x04000000

0:000> !locks -v

CritSec ntdll!RtlpProcessHeapsListLock+0 at 778d7620
LockCount          NOT LOCKED
RecursionCount     0
OwningThread       0
EntryCount         0
ContentionCount    0

CritSec +7a0248 at 007a0248
LockCount          NOT LOCKED
RecursionCount     0
OwningThread       0
EntryCount         0
ContentionCount    0

CritSec crashy_program!g_critical_section_with_debug_info+0 at 01342c48
LockCount          NOT LOCKED
RecursionCount     0
OwningThread       0
EntryCount         0
ContentionCount    0

CritSec crashy_program!crashpad::`anonymous namespace'::g_test_critical_section+0 at 01342be0
WaiterWoken        No
LockCount          0
RecursionCount     1
OwningThread       34b8
EntryCount         0
ContentionCount    0
*** Locked

Scanned 4 critical sections

R=mark@chromium.org
BUG=crashpad:52

Review URL: https://codereview.chromium.org/1392093003 .
2015-10-15 13:18:08 -07:00
Scott Graham
475ac81cce win: Implement CRASHPAD_SIMULATE_CRASH()
Windows requires the connection to the handler to do anything, so it
can't really be implemented or tested without CrashpadClient and the
connection machinery.

R=mark@chromium.org
BUG=crashpad:53

Review URL: https://codereview.chromium.org/1356383002 .
2015-09-25 13:45:32 -07:00
Scott Graham
6082aed2f2 win: Get Crashpad compiling under VS2015
R=mark@chromium.org
BUG=crashpad:1, chromium:440500

Review URL: https://codereview.chromium.org/1357833002 .
2015-09-21 10:51:15 -07:00
Scott Graham
81269ee676 win: Fix pipe leak on connection
The pipe handle was being leaked on connections (oops!). On XP this
resulted in the next test's CreateNamedPipe to fail, because the
previous one still existed (because all handles were not closed). More
recent OSs are more forgiving so I got away with the buggy code.

R=mark@chromium.org
BUG=crashpad:50

Review URL: https://codereview.chromium.org/1337953003 .
2015-09-11 15:34:35 -07:00
Scott Graham
3a886267aa win: Fix OpenProcess(PROCESS_ALL_ACCESS, ...) on XP
PROCESS_ALL_ACCESS was changed in later SDKs and the newer value fails
when run on XP with ERROR_ACCESS_DENIED. Use the old value to maintain
compatibility with XP.

R=mark@chromium.org
BUG=crashpad:50

Review URL: https://codereview.chromium.org/1337133002 .
2015-09-11 13:16:06 -07:00
Scott Graham
28c5da9080 win: Add version to client registration request
Follow up after suggestion in https://codereview.chromium.org/1301853002/.

R=mark@chromium.org
BUG=crashpad:1

Review URL: https://codereview.chromium.org/1314683008 .
2015-09-04 11:52:07 -07:00
Scott Graham
5de461e8c8 Refactor handler/main for Windows, implement CrashHandlerExceptionServer
BUG=crashpad:1
R=mark@chromium.org

Review URL: https://codereview.chromium.org/1314093002 .
2015-09-03 13:31:19 -07:00
Scott Graham
6978bf7646 win: Crash handler server
This replaces the registration server, and adds dispatch to a delegate
on crash requests.

(As you are already aware) we went around in circles on trying to come
up with a slightly-too-fancy threading design. All of them seemed to
have problems when it comes to out of order events, and orderly
shutdown, so I've gone back to something not-too-fancy.

Two named pipe instances (that clients connect to) are created. These
are used only for registration (which should take <1ms), so 2 should be
sufficient to avoid any waits. When a client registers, we duplicate
an event to it, which is used to signal when it wants a dump taken.

The server registers threadpool waits on that event, and also on the
process handle (which will be signalled when the client process exits).
These requests (in particular the taking of the dump) are serviced
on the threadpool, which avoids us needing to manage those threads,
but still allows parallelism in taking dumps. On process termination,
we use an IO Completion Port to post a message back to the main thread
to request cleanup. This complexity is necessary so that we can
unregister the threadpool waits without being on the threadpool, which
we need to do synchronously so that we can be sure that no further
callbacks will execute (and expect to have the client data around
still).

In a followup, I will readd support for DumpWithoutCrashing -- I don't
think it will be too difficult now that we have an orderly way to
clean up client records in the server.

R=cpu@chromium.org, mark@chromium.org, jschuh@chromium.org
BUG=crashpad:1,crashpad:45

Review URL: https://codereview.chromium.org/1301853002 .
2015-09-03 11:06:17 -07:00