In order to dump call frame information held in .eh_frame sections, the
dumper needs to know the proper base address to use for pointers encoded
using the DW_EH_PE_textrel encoding. This should be the start of the .text
section. However, due to a cut-and-paste typo, the dumper was supplying the
base address of the ".got" section instead.
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@564 4c0a9323-5329-0410-9bdc-e9ce6186880e
This patch allows the Breakpad minidump processor to use data from
STACK CFI records to generate stack traces for the ARM processor.
In the symbol dumper, we need a table mapping DWARF CFI register
numbers to their names: STACK CFI records refer to registers by name.
In the processor, we expand StackwalkerARM::GetCallerFrame to see if
there are STACK CFI records covering the callee, and then use those to
recover the caller's register values.
There's no good reason the ARM walker couldn't use the SimpleCFIWalker
interface declared in cfi_frame_info.h. Unfortunately, that interface
assumes that one can map register names to member pointers of the raw
context type, while MDRawContextARM uses an array to hold the
registers' values: C++ pointer-to-member types can't refer to elements
of member arrays. So we have to write out SimpleCFIWalker::FindCallerRegisters
in StackwalkerARM::GetCallerFrame.
We define enum MDARMRegisterNumbers in minidump_cpu_arm.h, for
convenience in referring to certain ARM registers with dedicated
purposes, like the stack pointer and the PC.
We define validity flags in StackFrameARM for all the registers, since
CFI could theoretically recover any of them. In the same vein, we
expand minidump_stackwalk.cc to print the values of all valid
callee-saves registers in the context --- and use the proper names for
special-purpose registers.
We provide unit tests that give full code and branch coverage (with
minor exceptions). We add a testing interface to StackwalkerARM that
allows us to create context frames that lack some register values.
a=jimblandy, r=mmentovai
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@553 4c0a9323-5329-0410-9bdc-e9ce6186880e
Extend google_breakpad::CFISection with the ability to produce
.eh_frame data. Entry headers have a different format, and pointers
can be encoded in new and fascinating ways.
Extend dwarf2reader::CallFrameInfo to be able to parse either DWARF
CFI or .eh_frame data, as determined by an argument to the
constructor. Cope with variations in header formats, encoded pointers,
and additional data in 'z' augmentation data blocks. Extend the unit
tests appropriately.
Extend dump_syms to look for a .eh_frame section, and if it is
present, find the necessary base addresess and parse its contents.
There's no need for DwarfCFIToModule to check the version numbers; if
CallFrameInfo can parse it, DwarfCFIToModule should be able to handle
it. Adjust tests accordingly.
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@552 4c0a9323-5329-0410-9bdc-e9ce6186880e
Define a new DWARF parser class, dwarf2reader::CallFrameInfo.
Extend google_breakpad::Module to store and write out 'STACK CFI' records.
Define a new google_breakpad::DwarfCFIToModule class, to accept DWARF
CFI data from the parser and populate a Module with the equivalent
STACK CFI records.
Extend the Linux symbol dumping tool, dump_syms, to use
dwarf2reader::CallFrameInfo, google_breakpad::DwarfCFIToModule, and
google_breakpad::Module to extract DWARF CFI from the executable or
shared library files and write it to the Breakpad symbol file.
Define CFISection, a new class derived from TestAssembler::Section,
for use in creating DWARF CFI data for test cases.
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@550 4c0a9323-5329-0410-9bdc-e9ce6186880e
FindSectionByName will return the first section whose name starts with
NAME, because strncmp stops the comparison once NAME's characters have
been found to match. The comparison stops before the terminating '\0'.
For example, if we search for the section named ".eh_frame", we may
get the section named ".eh_frame_hdr".
Instead, check that the section name section has enough space to store
the complete name with its terminating '\0', and then use strcmp,
which will never examine more than strlen(NAME) + 1 bytes from the
section name section, regardless of its contents, and will require the
terminating '\0' to match as well.
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@525 4c0a9323-5329-0410-9bdc-e9ce6186880e
Yes, classes are useful. But that doesn't mean that every function has
to gratuitously become a member function. The Google C++ Style Guide
does not require this silliness, since the function is in the
google_breakpad namespace anyway.
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@519 4c0a9323-5329-0410-9bdc-e9ce6186880e
This also includes some comments I promised Cary Coutant I'd write
about the appropriateness of processing attributes in EndAttributes
calls.
The Google C++ Style Guide requires each file to have an author notice
and a comment explaining the file's general purpose. For the record, I
don't think putting an author notice on the files is a good idea; it's
odd to have the original author retain prominence even if the file has
been heavily edited by others; the version control system answers this
question more accurately. This is only for Style Guide compliance. The
Apache group decided to discourage author annotations, partially for
these reasons:
http://mail-archives.apache.org/mod_mbox/jakarta-jmeter-dev/200402.mbox/%3C4039F65E.7020406@atg.com%3E
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@518 4c0a9323-5329-0410-9bdc-e9ce6186880e
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
This extends the ElfArchitecture function to recognize the
architectures it seemed to me that breakpad was most likely to see.
Also: the dumper has historically not provided very helpful error
messages. This patch adds a few that were convenient, but we should do
an audit for this.
a=jimblandy, r=ted.mielczarek
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@507 4c0a9323-5329-0410-9bdc-e9ce6186880e
This adds DWARF support to the Breakpad Linux dumper. This is
implemented as two handler classes: google_breakpad::DwarfCUToModule
accepts data from dwarf2reader::CompilationUnit, and
google_breakpad::DwarfLineToModule accepts data from a
dwarf2reader::LineInfo, each populating a google_breakpad::Module with
the results. Behaviors specific to particular source languages are
handled by instances of a new class, google_breakpad::Language.
An input executable may contain both STABS and DWARF debugging
information: the dumper automatically recognizes what sorts of
information are available, and integrates the data into a single
output file.
All classes have unit tests, providing line and branch coverage of all
interesting code. Unit tests are written using the Google C++ Testing
Framework, and the Google C++ Mocking Framework where appropriate.
a=jimblandy, r=ccoutant
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@497 4c0a9323-5329-0410-9bdc-e9ce6186880e
The StabsHandler class should not provide a fallback definition for
its Warning member function that just throws away warning messages.
It should require the consumer to provide an appropriate definition.
a=jimblandy, r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@442 4c0a9323-5329-0410-9bdc-e9ce6186880e
src/linux/common/module.h defines a new class, google_breakpad::Module,
that can represent the contents of a breakpad symbol file. Module::Write
writes a well-formed symbol file to the given stream.
src/linux/common/dump_symbols.cc can now lose its symbol-file-writing
code, and change DumpStabsHandler to populate a Module object, rather
than the old SymbolInfo/SourceFileInfo/... collection of types.
The code to compute function and line sizes, even in the absence of
reliable size data in STABS, is moved into a new Finalize method of
DumpStabsHandler, which is responsible for completing the Module's
contents.
a=jimblandy
r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@380 4c0a9323-5329-0410-9bdc-e9ce6186880e
With this patch, dump_symbols.cc no longer knows about the details of
the STABS debugging format; that is handled by the StabsReader class.
dump_symbols.cc provides a subclass of StabsHandler that builds
dump_symbols' own representation of the data.
a=jimblandy
r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@378 4c0a9323-5329-0410-9bdc-e9ce6186880e
Because the actual N_FUN strings in the .stabstr section contain type
information after the mangled name, representing this information
using a pointer into .stabstr, while efficient with memory, makes the
FuncInfo data structure STABS-specific: one must know the details of a
STABS N_FUN string's syntax to interpret FuncInfo::name. This patch
removes this STABS dependency from the data structure, and moves us
closer to having an appropriate structure for representing unified
STABS and DWARF data.
a=jimblandy
r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@375 4c0a9323-5329-0410-9bdc-e9ce6186880e
In STABS, if one function's line number information contains an N_SOL
entry to switch to a new source file, then the next function's line
data should pick up in the same source file where the prior function
left off. However, the Linux dumper restarts each function in the
compilation unit's main source file. This patch fixes that, so that
the output attributes the lines in subsequent functions to the correct
source files.
a=jimblandy
r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@373 4c0a9323-5329-0410-9bdc-e9ce6186880e
Let LineInfo structures point directly to their SourceLineInfo
structures, rather than holding the index of the file's name in the
.stabstr section in the early phases, and then later the holding
source_id of the file.
This is another step in the process of moving STABS-specific values
out of the types that represent the breakpad symbol data. When we're
done, the non-STABS structures will be something that we can populate
with both STABS and DWARF data --- or at least it will be more easily
replaced with such.
a=jimblandy
r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@371 4c0a9323-5329-0410-9bdc-e9ce6186880e
STABS information introduces a compilation unit with an N_SO entry
whose address is the start address of the file and whose string is the
name of the compilation unit's main source file. However, STABS
entries can only hold one address, so STABS indicates the compilation
unit's ending address with an N_SO entry whose name is empty.
Currently, the dumper's data structures simply create SourceFileInfo
structures with empty names for these end-of-unit N_SO entries. We
want to remove STABS-specific characteristics from these structures so
that we can replace them with an input-format-independent structure.
This moves end-of-compilation-unit addresses out of the symbol table
structure, and into their own list of boundary addresses.
a=jimblandy
r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@369 4c0a9323-5329-0410-9bdc-e9ce6186880e
Use a list of pointers to SourceFileInfo structures, not a list of the
structures themselves. This is preparation for a subsequent patch
which makes the data structures less STABS-specific.
This patch introduces a memory leak. If an included file is
referenced only by line entries for functions that LoadFuncSymbols
elected to omit from the func_info list, then its SourceFileInfo
structure is leaked when we destroy the name_to_file map. This leak
is fixed in a subsequent patch by letting the map of files by name own
the file objects.
a=jimblandy
r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@368 4c0a9323-5329-0410-9bdc-e9ce6186880e
Replace the sorted lists of files and functions with an array of
boundary addresses. This replaces CompareAddress with the default
comparison, and SortByAddress and NextAddress with the stock STL sort
and upper_bound algorithms, losing ~50 lines of code.
a=jimblandy
r=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@367 4c0a9323-5329-0410-9bdc-e9ce6186880e
In NextAddress, check both the file list and the function list for the
nearest boundary. Don't assume that, if we find any bounding entry in
the function list, that must be the nearest thing.
A=jimblandy
R=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@365 4c0a9323-5329-0410-9bdc-e9ce6186880e
The current arrangement would produce needless warnings if
WriteSymbolFile were ever used twice in the same program invocation.
Even if it weren't wrong, it's unnecessary, and local non-const static
variables require extra care when reading to be sure of their effect.
A=jimblandy
R=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@363 4c0a9323-5329-0410-9bdc-e9ce6186880e
With this patch, the time required to generate Breakpad symbols for
Firefox's libxul.so on a MacBook Pro 3,1 drops from 32s to 2s.
I verified that this patch had no effect on the output of dump_syms
when applied to firefox-bin and its libraries when built with -gstabs+.
A=jimblandy
R=nealsid
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@362 4c0a9323-5329-0410-9bdc-e9ce6186880e
