12 Commits

Author SHA1 Message Date
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
Mark Mentovai
952f787f4a doc: Standardize on “macOS” in comments
Use “macOS” as the generic unversioned name of the operating system in
comments. For version-specific references, use Mac OS X through 10.6, OS
X from 10.7 through 10.11, and macOS for 10.12.

Change-Id: I1ebee64fbf79200bc799d4a351725dd73257b54d
Reviewed-on: https://chromium-review.googlesource.com/408269
Reviewed-by: Robert Sesek <rsesek@chromium.org>
2016-11-08 19:21:44 +00:00
Mark Mentovai
c281e30f93 mac: Update the dyld_all_image_infos structure for 10.12
BUG=crashpad:120

Change-Id: I7b2df5f2de13517b2586569ce267bcb0ae845101
Reviewed-on: https://chromium-review.googlesource.com/353830
Reviewed-by: Robert Sesek <rsesek@chromium.org>
2016-06-20 16:14:24 +00:00
Mark Mentovai
cd1f8fa3d2 Tolerate weird cl_kernels modules on Mac OS X 10.11.
The cl_kernels bug (Apple bug 20239912) in which cl_kernels modules show
up with an __LD,__compact_unwind section inside the __TEXT segment, is
still present in Mac OS X 10.11. This results in these warnings and a
failure to load the module:

[pid:tid:yyyymmdd,hhmmss.uuuuuu:WARNING
mach_o_image_segment_reader.cc:142] section.segname incorrect in
segment __TEXT, section __LD,__compact_unwind 3/6, load command 0x19
0/6, module cl_kernels, address 0x10e964000

BUG=crashpad:42
TEST=crashpad_snapshot_test ProcessReader.*Modules
R=rsesek@chromium.org

Review URL: https://codereview.chromium.org/1276573002 .
2015-08-05 17:13:11 -04:00
Erik Chen
6d121a1b88 Suppress a partial-availability warning in process_reader_test.cc.
BUG=491157
R=rsesek@chromium.org

Review URL: https://codereview.chromium.org/1153763007

Patch from Erik Chen <erikchen@chromium.org>.
2015-05-22 15:57:22 -04:00
Mark Mentovai
809ea8158d test: Move util/test to its own top-level directory, test.
After 9e79ea1da719, it no longer makes sense for crashpad_util_test_lib
to “hide” in util/util_test.gyp. All of util/test is moved to its own
top-level directory, test, which all other test code is allowed to
depend on. test, too, is allowed to depend on all other non-test code.

In a future change, when crashpad_util_test_lib gains a dependency on
crashpad_client, it won’t look so weird for something in util (even
though it’s in util/test) to depend on something in client, because the
thing that needs to depend on client will live in test, not util.

BUG=crashpad:33
R=scottmg@chromium.org

Review URL: https://codereview.chromium.org/1051533002
2015-03-31 17:44:14 -04:00
Mark Mentovai
5d0a133ecd Tolerate weird cl_kernels modules.
cl_kernels modules (OpenCL kernels) are not structured as correct Mach-O
images on Mac OS X 10.10, but they’re present frequently enough that
it’s worth detecting and tolerating their quirks.

As discussed in
https://groups.google.com/a/chromium.org/d/msg/crashpad-dev/NaB7PrfW04g/FanqNJkVBfUJ

Apple bug: https://openradar.appspot.com/20239912

TEST=crashpad_snapshot_test ProcessReader.*
R=rsesek@chromium.org

Review URL: https://codereview.chromium.org/1019243006
2015-03-23 16:27:42 -04:00
Mark Mentovai
56399b2553 snapshot/mac: MachOImageAnnotationsReader test shouldn’t crash with a
nullptr ProcessReader::Module.

Prior to 64b87325b9de, the alignment problem meant that the Module for
dyld was looking at the wrong address instead of dyld’s correct load
address when a 32-bit process attempted to examine a crashing 64-bit
process. This resulted in a crash during the
MachOImageAnnotationsReader.CrashDyld test.

ProcessReader::Module pointers are permitted to be nullptr. This allows
minimal module data (its name) to be preserved even when no sense can be
made of the module based on its load address. The producer,
ProcessReader::InitializeModules(), and the non-test consumer,
ModuleSnapshotMac::Initialize(), both accept this correctly. The
producer’s documentation is updated to call this out. The ProcessReader
test is also updated to tolerate this case without crashing by adding
assertions.

TEST=snapshot_test MachOImageAnnotationsReader.*, ProcessReader.*
R=rsesek@chromium.org

Review URL: https://codereview.chromium.org/989713002
2015-03-08 21:02:42 -04:00
Scott Graham
892c29e8ba Reorganize Multiprocess and implement for Windows
- Various "FD" to "Handle"
- Existing Multiprocess implementation moves to _posix.
- Stub implementation for _win.

At the moment, multiprocess_exec_win.cc contains implementations of both
Multiprocess methods and MultiprocessExec functions. This will need more
work in the future, but reflects the idea that all tests should be in
terms of MultiprocessExec eventually.

Currently, this works sufficiently to have util_test succeed (including
multiprocess_exec_test, and the recently ported HTTPTransport tests.)

R=mark@chromium.org
BUG=crashpad:1, crashpad:7

Review URL: https://codereview.chromium.org/880763002
2015-01-28 14:49:42 -08:00
Scott Graham
10165ce449 Cross platform low level file IO wrappers
Rename fd_io to file_io, and ReadFD to ReadFile, etc.

file_io.cc is the higher level versions that call the basic ReadFile/WriteFile
and then file_io_posix.cc and file_io_win.cc are the implementations of
those functions.

The Windows path is as yet untested, lacking the ability to link the test binary.

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

Review URL: https://codereview.chromium.org/811823003
2014-12-17 14:35:18 -08:00
Mark Mentovai
de0979b930 C++11: Use type aliases instead of typedefs.
This replaces all occurrences of “typedef Y X;” with “using X = Y;”.

R=rsesek@chromium.org

Review URL: https://codereview.chromium.org/700143004
2014-11-05 14:09:01 -05:00
Mark Mentovai
bcae4d94d5 Create snapshot/mac and move some files from snapshot and util to there.
TEST=snapshot_test, util_test CheckedMachAddressRange.*
R=rsesek@chromium.org

Review URL: https://codereview.chromium.org/666483002
2014-10-17 13:41:45 -04:00