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* fix pointer style to match the style guideMike Frysinger2020-07-151-4/+4
| | | | | | | | | | We do this in a lot of places, but we're inconsistent. Normalize the code to the Google C++ style guide. Change-Id: Ic2aceab661ce8f6b993dda21b1cdf5d2198dcbbf Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2262932 Reviewed-by: Sterling Augustine <saugustine@google.com> Reviewed-by: Mark Mentovai <mark@chromium.org>
* Handle very large stack tracesLeonard Mosescu2017-07-121-8/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The main motivation for this change is to handle very large stack traces, normally the result of infinite recursion. This part is actually fairly simple, relaxing a few self-imposed limits on how many frames we can unwind and the max size for stack memory. Relaxing these limits requires stricter and more consistent checks for stack unwinding. There are a number of unwinding invariants that apply to all the platforms: 1. stack pointer (and frame pointer) must be within the stack memory (frame pointer, if preset, must point to the right frame too) 2. unwinding must monotonically increase SP (except for the first frame unwind, this must be a strict increase) 3. Instruction pointer (return address) must point to a valid location 4. stack pointer (and frame pointer) must be appropriately aligned This change is focused on 2), which is enough to guarantee that the unwinding doesn't get stuck in an infinite loop. 1) is implicitly validated part of accessing the stack memory (explicit checks might be nice though). 4) is ABI specific and while it may be valuable in catching suspicious frames is not in the scope of this change. 3) is also an interesting check but thanks to just-in-time compilation it's more complex than just calling StackWalker::InstructionAddressSeemsValid() and we don't want to drop parts of the callstack due to an overly conservative check. Bug: chromium:735989 Change-Id: I9aaba77c7fd028942d77c87d51b5e6f94e136ddd Reviewed-on: https://chromium-review.googlesource.com/563771 Reviewed-by: Mark Mentovai <mark@chromium.org> Reviewed-by: Ivan Penkov <ivanpe@chromium.org>
* Provide initial EBX value to FPO frame data evaluatorScott Graham2016-10-141-4/+14
| | | | | | | | | | | | | EBX is sometimes used in "WIN FRAME 4" programs. Not providing the initial value was causing the evaluation in some frames of ntdll, resulting in a fallback to scanning and a failed stack walk. R=mark@chromium.org BUG=chromium:651453 Change-Id: I94a8184e1eed72b0d0e3212fe323fbdd10d56da5 Reviewed-on: https://chromium-review.googlesource.com/398059 Reviewed-by: Mark Mentovai <mark@chromium.org>
* Use register %ebp (instead of %esp) when calculating the value ofivan.penkov@gmail.com2013-11-051-8/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | .raSearchStart in the cases where there are alignment operators in the program string. If alignment operators are found in the program string, the current value of %ebp must be valid and it is the only reliable data point that can be used for getting to the previous frame. Previously, the .raSearchStart calculation was based on %esp and when %esp is aligned in the current frame (which is a lossy operation) the resulting .raSearchStart cannot was incorrect. There is code that is trying to work around this problem (scanning of up to 3 words for a return address) which is unreliable and it doesn't work in many cases (e.g. when the alignment is on a 64-byte boundary). This fix is already deployed in Google and it was measured to reduce the number of wrong stack traces (for Windows crashes) by 45%. No regressions have been found so far. Here is an example of an issue that was fixed by this change (where register %esp is aligned on the 64-byte boundary and the workarounds that we already had didn't work): https://code.google.com/p/chromium/issues/detail?id=311359 0:013> uf chrome_59630000!base::MessagePumpForIO::DoRunLoop 518 59685c39 55 push ebp 518 59685c3a 8bec mov ebp,esp 518 59685c3c 83e4c0 and esp,0FFFFFFC0h <== 64-byte boundary 518 59685c3f 83ec34 sub esp,34h 518 59685c42 53 push ebx 518 59685c43 56 push esi Program string contains 64-byte alignment: $T1 .raSearch = $T0 $T1 4 - 64 @ = $ebp $T1 4 - ^ = $eip $T1 ^ = $esp $T1 4 + = $20 $T0 56 - ^ = $23 $T0 60 - ^ = $24 $T0 64 - ^ = Review URL: https://breakpad.appspot.com/694002 git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1232 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Allow setting a limit on the number of frames to be recovered by stack scanning.ted.mielczarek@gmail.com2013-08-191-11/+18
| | | | | | Patch by Julian Seward <jseward@acm.org> R=ted at https://bugzilla.mozilla.org/show_bug.cgi?id=894264 git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1206 4c0a9323-5329-0410-9bdc-e9ce6186880e
* More robust stack walks when the IP address in the context frame is invalid ↵ivan.penkov@gmail.com2013-06-261-10/+29
| | | | | | | | | | | | | (or not in a known module). This is achieved by: 1. Extending the span of the scan for return address in the conext frame. Initially, I wanted to extend the span of the scan for all frames but then I noticed that there is code for ARM already that is extending the search only for the context frame. This kind of makes sense so I decided to reuse the same idea everywhere. 2. Attempting to restore the EBP chain after a successful scan for return address so that the stackwalker can switch back to FRAME_TRUST_CFI for the rest of the frames when possible. I also fixed the lint errors in the files touched. Review URL: https://breakpad.appspot.com/605002 git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1193 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Use stdint types everywhereted.mielczarek@gmail.com2013-03-061-21/+21
| | | | | | R=mark at https://breakpad.appspot.com/535002/ git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1121 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Print the correct return address, even on architectures where ↵jimblandy2013-01-221-8/+12
| | | | | | | | | StackFrame::instruction is offset. a=bruce.dawson, r=jimblandy git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1105 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Move scoped_ptr.h to commonted.mielczarek@gmail.com2013-01-171-1/+1
| | | | | | R=mark at https://breakpad.appspot.com/509002/ git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1096 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Allow processing dumps with missing stack memory for some threadsted.mielczarek@gmail.com2012-11-061-3/+3
| | | | | | r=mkrebs at https://breakpad.appspot.com/413002/ git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1077 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Wrong %ebp after skipping a frame for which the instruction pointer is not ↵ivan.penkov@gmail.com2012-11-021-25/+35
| | | | | | | | | | in a known module. http://breakpad.appspot.com/494002/ git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1076 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Refactor the logic of resolving source line info into helper class.SiyangXie@gmail.com2012-10-101-36/+35
| | | | | | | http://breakpad.appspot.com/459002/ git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1068 4c0a9323-5329-0410-9bdc-e9ce6186880e
* This is a fix for a stackwalker_x86 issue which has toivan.penkov@gmail.com2012-06-121-3/+19
| | | | | | | | | | do with FPO (frame-pointer-omission) optimized context frames where the context frame represents a Windows System call stub. git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@971 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Support for .raSearch in the x86 stackwalkermark@chromium.org2012-02-231-4/+15
| | | | | | | Patch by Benjamin Smedberg <bsmedberg@gmail.com> git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@927 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Fix some apparently longstanding crash bugs in Stackwalker implementations ↵ted.mielczarek2011-01-241-2/+3
| | | | | | | | when resolver is NULL. R=mark at http://breakpad.appspot.com/257001 git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@761 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Add stack-scanning fallback to Stackwalker{AMD64,ARM}.ted.mielczarek2010-10-011-1/+1
| | | | | | R=jimb at http://breakpad.appspot.com/206001/show git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@704 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Refactor some bits of StackWalkerX86 / StackFrameX86 out into their ↵ted.mielczarek2010-10-011-32/+9
| | | | | | | | respective parent classes so they can be used by other architecture implementations. R=jimb at http://breakpad.appspot.com/205001/show git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@703 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Breakpad: Add minidump processor support for DWARF Call Frame Information.jimblandy2010-03-161-3/+68
| | | | | | | | | | | | | | | | | | | | | | | | Add a CFIFrameInfo class (named for symmetry with WindowsFrameInfo) to represent the set of STACK CFI rules in effect at a given instruction, and apply them to a set of register values. Provide a SimpleCFIWalker class template, to allow the essential CFI code to be shared amongst the different architectures. Teach BasicSourceLineResolver to partially parse 'STACK CFI' records, and produce the set of rules in effect at a given instruction on demand, by combining the initial rule set and the appropriate rule deltas in a CFIFrameInfo object. Adapt StackwalkerX86 and StackFrameX86 to retrieve, store, and apply CFI stack walking information. Add validity flags for all the general-purpose registers to StackFrameX86::ContextValidity. a=jimblandy, r=mmentovai git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@549 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Breakpad: Update copyright notice years on all files changed in 2010.jimblandy2010-02-091-1/+1
| | | | | | | | | | We've gotten mixed advice from the lawyery types about whether this matters. But it's easy enough to do. a=jimblandy, r=nealsid git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@517 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Breakpad processor: Segregate STACK WIN vs. traditional stack walking.jimblandy2010-02-051-168/+227
| | | | | | | | | | | | | This patch moves the code for finding caller frames using STACK WIN data and the code to do so using the traditional frame layout (%ebp points at saved %ebp, pushed just after return address) into their own functions. In addition to making things a little clearer, this is preparation for adding support for STACK CFI records into the mix. a=jimblandy, r=mmentovai git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@512 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Breakpad x86 Stack Walker: Pass "out" parameters by address, not reference.jimblandy2010-02-051-6/+6
| | | | | | | | | | | | The Google C++ Style Guide requires all parameters passed by reference to be labeled 'const', and says that pointers should be used for output arguments. This patch brings google_breakpad::StackwalkerX86 into line. a=jimblandy, r=mmentovai git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@510 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Breakpad processor: Save Windows unwinding data earlier in x86 walker.jimblandy2010-02-051-3/+4
| | | | | | | | | | | | | | | | | | | At the moment, StackwalkerX86::GetCallerFrame doesn't save the WindowsFrameInfo that it finds for a frame unless it successfully constructs the caller frame. This means that the windows_frame_info field of the last frame on the stack is left unset, even when that frame does have windows unwinding information. This is not user-visible behavior, so it doesn't matter, but it is a blemish on the interface, and unit tests (added in a later patch) expect it. This patch saves the information in the frame as soon as we find it. a=jimblandy, r=mmentovai git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@508 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Breakpad processor: Don't pass Windows stack walking information to all walkers.jimblandy2010-01-141-9/+21
| | | | | | | | | | | | | | | | | | | | | At the moment, the StackWalker GetCallerFrame member function expects a vector of WindowsFrameInfo structures, even though WindowsFrameInfo is only used or useful on one one implementation (StackWalkerX86). This patch changes StackWalker::GetCallerFrame to no longer expect the WindowsFrameInfo structures, and changes all implementations to match. In particular, StackWalkerX86 is changed to find the WindowsFrameInfo data itself, and store a pointer to whatever it got in the StackFrame object itself (which is really a StackFrameX86). To allow GetCallerFrame implementations to look up stack walking data, StackWalker::resolver_ needs to be made protected, not private. a=jimblandy, r=mmentovai git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@491 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Issue 49012: Breakpad Processor: Rename 'StackFrameInfo' structure to ↵jimblandy2009-12-231-8/+8
| | | | | | | | | | | | | | | 'WindowsFrameInfo'. Also, rename stack_frame_info.h to windows_frame_info.h. If it seems odd to have functions like FillSourceLineInfo returning Windows-specific data structures... well, it is! This patch just makes it more obvious what's going on. a=jimblandy, r=nealsid git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@471 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Fix when walking stack when no module list is present and the return address ↵nealsid2009-10-301-1/+1
| | | | | | | | | | | | | | | has to be scanned. http://breakpad.appspot.com/36002 R=doshimun A=nealsid git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@420 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Let x86 stackwalker scan stack in cases where program evaluation fails. ↵ted.mielczarek2009-10-081-26/+56
| | | | | | Original patch by Jeff Muizelaar <jmuizelaar@mozilla.com> with some changes by me. r=mento at http://breakpad.appspot.com/32003/show git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@409 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Add logging to minidump processor (#82). Part 2: add messages to the rest ofmmentovai2007-05-211-2/+10
| | | | | | | | | the processor. r=ted.mielczarek http://groups.google.com/group/google-breakpad-dev/browse_thread/thread/cf56b767383a5d4b git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@172 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Stacks (still) truncated on win32 (#165). Patch by Benjamin Smedberg. r=memmentovai2007-05-081-9/+5
| | | | | | | | | | Don't require a program string to reset %ebp, as not all program strings set this value. http://groups.google.com/group/google-breakpad-dev/browse_thread/thread/ee4854ae7ffce94e git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@163 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Truncated Windows/x86 stacks when using FPO. Add stack scanning to recovermmentovai2007-04-201-2/+115
| | | | | | | | | instruction and frame pointers with better reliability. r=bryner http://groups.google.com/group/google-breakpad-dev/browse_thread/thread/e74af03fb0629aa0 git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@146 4c0a9323-5329-0410-9bdc-e9ce6186880e
* s/an breakpad/a breakpad/ (#127), patch by techtonik, r=memmentovai2007-03-231-1/+1
| | | | | | | http://groups.google.com/group/google-breakpad-dev/browse_thread/thread/9610c2878a2bcdc git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@131 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Rename Airbag to Breakpad.mmentovai2007-02-141-6/+6
| | | | git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@122 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Communicate OS and CPU to SymbolSupplier (#107). r=brynermmentovai2007-01-101-2/+3
| | | | | | | | | | Interface change: moved a few fields around in ProcessState; added new arguments to Stackwalker and SymbolSupplier. http://groups.google.com/group/airbag-dev/browse_thread/thread/17e4a48ec3ede932 git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@101 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Add an abstract interface to SourceLineResolver, and allow any implementationbryner2006-12-111-2/+3
| | | | | | | | | to be used with MinidumpProcessor. The basic SourceLineResolver is now a public interface (#89) git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@83 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Module API (#32). r=waylonis, brynermmentovai2006-12-051-2/+2
| | | | | | | | | | | | | | | | | | | - Introduces a standard API for dealing with modules. MinidumpModule is now a concrete implementation of this API. Code may interact with single modules using the CodeModule interface, and collections of modules using its container, the CodeModules interface. - CodeModule is used directly by SymbolSupplier implementations and SourceLineResolver. Reliance on the specific implementation in MinidumpModule has been eliminated. - Module lists are now added to ProcessState objects. Module references in each stack frame are now pointers to objects in these module lists. - The sample minidump_stackwalk tool prints the module list after printing all threads' stacks. http://groups.google.com/group/airbag-dev/browse_frm/thread/a9c0550edde54cf8 git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@74 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Move headers for exported interfaces into src/google_airbag (#51). r=brynermmentovai2006-11-061-3/+3
| | | | | | | http://groups.google.com/group/airbag-dev/browse_thread/thread/e01f177386e8794a git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@60 4c0a9323-5329-0410-9bdc-e9ce6186880e
* minidump_stackwalk should use MinidumpProcessor (#64). r=brynermmentovai2006-10-271-3/+3
| | | | | | | | | | | | | | | | | | | | | | | - minidump_stackwalk is now much more useful as a debugging tool and even as a standalone tool. - Reimplementation of minidump_stackwalk around MinidumpProcessor. - minidump_stackwalk displays all pertinent information returned by MinidumpProcessor in the ProcessState. - New PathnameStripper::File static utility method to display only the leaf file name in a pathname, cleaning up minidump_stackwalk's output. - New SimpleSymbolSupplier class, which implements a simple filesystem-based symbol supplier compatible with the layout used by Microsoft Symbol Server and its client cache. - minidump_stackwalk now accepts an optional second argument, a pathname to use as a symbol directory for a SimpleSymbolSupplier. - Updated test data to be compatible with SimpleSymbolSupplier, and added test data for kernel32.pdb. Test data converted from CRLF line endings to LF. http://groups.google.com/group/airbag-dev/browse_thread/thread/cce30a84f6b2d728 git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@53 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Fix minor style problems (#58). r=brynermmentovai2006-10-251-2/+3
| | | | | | | http://groups.google.com/group/airbag-dev/browse_thread/thread/bbcecab979fa82bc git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@49 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Make stack_frame_info vector hold linked_ptrs instead of objects;mmentovai2006-10-231-8/+14
| | | | | | | | | | | | | make Stackwalker::Walk create and return a CallStack instead of filling a caller-supplied one (#54). r=bryner Interface change: Stackwalker::Walk and MinidumpProcessor::Process now return a new CallStack*. http://groups.google.com/group/airbag-dev/browse_thread/thread/d2bad5d7c115c3fe git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@45 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Handle frame pointer omission, (#21), part 4 (final part!): FPO stackwalker.mmentovai2006-10-201-52/+241
| | | | | | | | | | | | | r=bryner - This change allows Airbag to properly walk win32 stacks produced by code built with MSVC's frame pointer omission optimization (/Oy). This optimization is enabled at /O1 and /O2. - There too many interface and file format changes to list here. http://groups.google.com/group/airbag-dev/browse_thread/thread/85ce85bfa8457ece git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@42 4c0a9323-5329-0410-9bdc-e9ce6186880e
* ppc stackwalker (#30). r=brynermmentovai2006-09-251-19/+16
| | | | | | | | | | | | - Implementation of PowerPC stackwalker. Tested using stackwalker_selftest (#18). - Hook up processor-side multi-CPU support in MinidumpProcessor and minidump_stackwalk using the new Stackwalker::StackwalkerForCPU method. http://groups.google.com/group/airbag-dev/browse_thread/thread/1c2fa7c5182a77a9 git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@34 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Add ppc support to minidump reader (#27). r=bryner.mmentovai2006-09-221-3/+4
| | | | | | | | | | | | - Uses new MDRawContextPPC structure from #25. - Interface change: (MinidumpContext).context() replaced with GetContextCPU to determine CPU type and GetContextX86/GetContextPPC to get CPU-specific context. http://groups.google.com/group/airbag-dev/browse_thread/thread/f6c2e9cab2832b4c git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@33 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Relicense to BSD (#29). r=brynermmentovai2006-09-201-10/+25
| | | | | | | http://groups.google.com/group/airbag-dev/browse_thread/thread/5f19f13fc172c4e0 git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@31 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Follow-up to #26: get rid of supplier_data, it's not really needed sincebryner2006-09-201-3/+2
| | | | | | | the caller can implement their own supplier object. r=mmentovai. git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@27 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Get rid of CrashReport, and rename CrashReportProcessor to MinidumpProcessorbryner2006-09-191-2/+2
| | | | | | | | (#26) r=mmentovai. git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@26 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Add support to the StackWalker for resolving symbols, using abryner2006-09-081-2/+4
| | | | | | | | | | | | caller-implemented SymbolSupplier object to get a symbol file. Add a CrashReportProcessor object which provides a simple API for processing a CrashReport struct, given a SymbolSupplier and a minidump file. r=mmentovai (#17)) git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@18 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Conform to style guidelines.mmentovai2006-09-071-2/+2
| | | | | | | | | | | | - In class definitions, one-space indent for public/protected/private. - Multi-line initializer format puts comma at end of line. Also: - Eliminate the long list of friends in Minidump by making swap() public. (People who need to access unknown stream types directly will need access to swap() too.) git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@16 4c0a9323-5329-0410-9bdc-e9ce6186880e
* Initial implementation of x86 stackwalker (#9). r=brynermmentovai2006-09-061-0/+103
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@12 4c0a9323-5329-0410-9bdc-e9ce6186880e