This adds a "self" argument to to_supports_btrace. Due to how one
implementation of this method is shared with gdbserver this required a
small change to gdbserver as well.
2014-02-19 Tom Tromey <tromey@redhat.com>
* common/linux-btrace.c (linux_supports_btrace): Add "ops"
argument.
* common/linux-btrace.h (linux_supports_btrace): Update.
* remote.c (remote_supports_btrace): Add "self" argument.
* target-delegates.c: Rebuild.
* target.c (target_supports_btrace): Remove.
* target.h (struct target_ops) <to_supports_btrace>: Add
target_ops argument.
(target_supports_btrace): New define.
2014-02-19 Tom Tromey <tromey@redhat.com>
* target.h (struct target_ops) <supports_btrace>: Add target_ops
argument.
(target_supports_btrace): Update.
This patch replaces some code in the record targets with target method
delegation.
record-full.c stores pointers to many target methods when the record
target is pushed. Then it later delegates some calls via these. This
is wrong because it violates the target stack contract. In particular
it is ok to unpush a target at any stratum, but record-full does not
keep track of this, so it could potentially call into an unpushed
target.
This patch fixes the problem by using the newly-introduced generic
approach to target delegation for the methods in question.
2014-02-19 Tom Tromey <tromey@redhat.com>
* record-full.c (record_full_beneath_to_resume_ops)
(record_full_beneath_to_resume, record_full_beneath_to_wait_ops)
(record_full_beneath_to_wait)
(record_full_beneath_to_store_registers_ops)
(record_full_beneath_to_store_registers)
(record_full_beneath_to_xfer_partial_ops)
(record_full_beneath_to_xfer_partial)
(record_full_beneath_to_insert_breakpoint_ops)
(record_full_beneath_to_insert_breakpoint)
(record_full_beneath_to_remove_breakpoint_ops)
(record_full_beneath_to_remove_breakpoint)
(record_full_beneath_to_stopped_by_watchpoint)
(record_full_beneath_to_stopped_data_address)
(record_full_beneath_to_async, tmp_to_resume_ops, tmp_to_resume)
(tmp_to_wait_ops, tmp_to_wait, tmp_to_store_registers_ops)
(tmp_to_store_registers, tmp_to_xfer_partial_ops)
(tmp_to_xfer_partial, tmp_to_instmp_to_insert_breakpoint_ops)
(tmp_to_insert_breakpoint, tmp_to_remove_breakpoint_ops)
(tmp_to_remove_breakpoint, tmp_to_stopped_by_watchpoint)
(tmp_to_stopped_data_address, tmp_to_async): Remove.
(record_full_open_1, record_full_open): Update. Use RECORD_IS_USED.
(record_full_resume, record_full_wait_1)
(record_full_stopped_by_watchpoint, record_full_stopped_data_address)
(record_full_store_registers, record_full_xfer_partial)
(record_full_insert_breakpoint, record_full_remove_breakpoint)
(record_full_async, record_full_core_xfer_partial): Use target
delegation.
* target-delegates.c: Rebuild.
* target.c (current_xfer_partial): Remove.
(update_current_target): Do not INHERIT or de_fault
to_insert_breakpoint, to_remove_breakpoint,
to_stopped_data_address, to_stopped_by_watchpoint, to_can_async_p,
to_is_async_p, to_async. Do not set to_xfer_partial field.
(default_xfer_partial): Simplify.
(current_xfer_partial): Remove.
(target_wait, target_resume): Simplify.
(find_default_can_async_p, find_default_is_async_p): Update.
(init_dummy_target): Don't set to_can_async_p, to_is_async_p,
to_xfer_partial, to_stopped_by_watchpoint,
to_stopped_data_address.
(target_store_registers): Simplify.
(forward_target_remove_breakpoint)
(forward_target_insert_breakpoint): Remove.
(target_remove_breakpoint, target_insert_breakpoint)
(debug_to_insert_breakpoint, debug_to_remove_breakpoint): Update.
* target.h (struct target_ops) <to_resume, to_wait,
to_store_registers, to_insert_breakpoint, to_remove_breakpoint,
to_stopped_by_watchpoint, to_stopped_data_address, to_can_async_p,
to_is_async_p, to_async, to_xfer_partial>: Add TARGET_DEFAULT
markup.
(forward_target_remove_breakpoint)
(forward_target_insert_breakpoint): Remove.
* record-btrace.c (record_btrace_remove_breakpoint): Delegate
directly.
(record_btrace_insert_breakpoint): Delegate directly.
This patch adds a new script, call make-target-delegates, which
auto-generates some target delegation code based on annotations in
target.h. This adds the new delegation macros, the new generated
file, and adds the necessary calls to the new generated functions to
target.c. It doesn't, however, add any actual annotations to the
target methods, leaving these for separate patches.
2014-02-19 Tom Tromey <tromey@redhat.com>
PR build/7701:
* target-delegates.c: New file.
* target.c: Include target-delegates.c.
(init_dummy_target): Call install_dummy_methods.
(complete_target_initialization): Call install_delegators.
* target.h (TARGET_DEFAULT_IGNORE, TARGET_DEFAULT_NORETURN)
(TARGET_DEFAULT_RETURN, TARGET_DEFAULT_FUNC): New defines.
* make-target-delegates: New file.
This patch adds find_target_at to determine whether a target appears
at a given stratum. This new function lets us clean up
find_record_target a bit, and is generally useful.
2014-02-19 Tom Tromey <tromey@redhat.com>
* record.c (find_record_target): Use find_target_at.
* target.c (find_target_at): New function.
* target.h (find_target_at): Declare.
This patch does the conversion of to_xfer_partial from
LONGEST (*to_xfer_partial) (struct target_ops *ops,
enum target_object object, const char *annex,
gdb_byte *readbuf, const gdb_byte *writebuf,
ULONGEST offset, ULONGEST len);
to
enum target_xfer_status (*to_xfer_partial) (struct target_ops *ops,
enum target_object object, const char *annex,
gdb_byte *readbuf, const gdb_byte *writebuf,
ULONGEST offset, ULONGEST len, ULONGEST *xfered_len);
It changes to_xfer_partial return the transfer status and the transfered
length by *XFERED_LEN. Generally, the return status has three stats,
- TARGET_XFER_OK,
- TARGET_XFER_EOF,
- TARGET_XFER_E_XXXX,
See the comments to them in 'enum target_xfer_status'. Note that
Pedro suggested not name TARGET_XFER_DONE, as it is confusing,
compared with "TARGET_XFER_OK". We finally name it TARGET_XFER_EOF.
With this change, GDB core can handle unavailable data in a convenient
way.
The rationale behind this change was mentioned here
https://sourceware.org/ml/gdb-patches/2013-10/msg00761.html
Consider an object/value like this:
0 100 150 200 512
DDDDDDDDDDDxxxxxxxxxDDDDDD...DDIIIIIIIIIIII..III
where D is valid data, and xxx is unavailable data, and I is beyond
the end of the object (Invalid). Currently, if we start the
xfer at 0, requesting, say 512 bytes, we'll first get back 100 bytes.
The xfer machinery then retries fetching [100,512), and gets back
TARGET_XFER_E_UNAVAILABLE. That's sufficient when you're either
interested in either having the whole of the 512 bytes available,
or erroring out. But, in this scenario, we're interested in
the data at [150,512). The problem is that the last
TARGET_XFER_E_UNAVAILABLE gives us no indication where to
start the read next. We'd need something like:
get me [0,512) >>>
<<< here's [0,100), *xfered_len is 100, returns TARGET_XFER_OK
get me [100,512) >>> (**1)
<<< [100,150) is unavailable, *xfered_len is 50, return TARGET_XFER_E_UNAVAILABLE.
get me [150,512) >>>
<<< here's [150,200), *xfered_len is 50, return TARGET_XFER_OK.
get me [200,512) >>>
<<< no more data, return TARGET_XFER_EOF.
This naturally implies pushing down the decision of whether
to return TARGET_XFER_E_UNAVAILABLE or something else
down to the target. (Which kinds of leads back to tfile
itself reading from RO memory from file (though we could
export a function in exec.c for that that tfile delegates to,
instead of re-adding the old code).
Beside this change, we also add a macro TARGET_XFER_STATUS_ERROR_P to
check whether a status is an error or not, to stop using "status < 0".
This patch also eliminates the comparison between status and 0.
No target implementations to to_xfer_partial adapts this new
interface. The interface still behaves as before.
gdb:
2014-02-11 Yao Qi <yao@codesourcery.com>
* target.h (enum target_xfer_error): Rename to ...
(enum target_xfer_status): ... it. New. All users updated.
(enum target_xfer_status) <TARGET_XFER_OK>, <TARGET_XFER_EOF>:
New.
(TARGET_XFER_STATUS_ERROR_P): New macro.
(target_xfer_error_to_string): Remove declaration.
(target_xfer_status_to_string): Declare.
(target_xfer_partial_ftype): Adjust it.
(struct target_ops) <to_xfer_partial>: Return
target_xfer_status. Add argument xfered_len. Update
comments.
* target.c (target_xfer_error_to_string): Rename to ...
(target_xfer_status_to_string): ... it. New. All callers
updated.
(target_read_live_memory): Likewise. Call target_xfer_partial
instead of target_read.
(memory_xfer_live_readonly_partial): Return
target_xfer_status. Add argument xfered_len.
(raw_memory_xfer_partial): Likewise.
(memory_xfer_partial_1): Likewise.
(memory_xfer_partial): Likewise.
(target_xfer_partial): Likewise. Check *XFERED_LEN is set
properly. Update debug message.
(default_xfer_partial, current_xfer_partial): Likewise.
(target_write_partial): Likewise.
(target_read_partial): Likewise. All callers updated.
(read_whatever_is_readable): Likewise.
(target_write_with_progress): Likewise.
(target_read_alloc_1): Likewise.
* aix-thread.c (aix_thread_xfer_partial): Likewise.
* auxv.c (procfs_xfer_auxv): Likewise.
(ld_so_xfer_auxv, memory_xfer_auxv): Likewise.
* bfd-target.c (target_bfd_xfer_partial): Likewise.
* bsd-kvm.c (bsd_kvm_xfer_partial): Likewise.
* bsd-uthread.c (bsd_uthread_xfer_partia): Likewise.
* corefile.c (read_memory): Adjust.
* corelow.c (core_xfer_partial): Likewise.
* ctf.c (ctf_xfer_partial): Likewise.
* darwin-nat.c (darwin_read_dyld_info): Likewise. All callers
updated.
(darwin_xfer_partial): Likewise.
* exec.c (section_table_xfer_memory_partial): Likewise. All
callers updated.
(exec_xfer_partial): Likewise.
* exec.h (section_table_xfer_memory_partial): Update
declaration.
* gnu-nat.c (gnu_xfer_memory): Likewise. Assert 'res' is not
negative.
(gnu_xfer_partial): Likewise.
* ia64-hpux-nat.c (ia64_hpux_xfer_memory_no_bs): Likewise.
(ia64_hpux_xfer_memory, ia64_hpux_xfer_uregs): Likewise.
(ia64_hpux_xfer_solib_got): Likewise.
* inf-ptrace.c (inf_ptrace_xfer_partial): Likewise. Change
type of 'partial_len' to ULONGEST.
* inf-ttrace.c (inf_ttrace_xfer_partial): Likewise.
* linux-nat.c (linux_xfer_siginfo ): Likewise.
(linux_nat_xfer_partial): Likewise.
(linux_proc_xfer_partial, linux_xfer_partial): Likewise.
(linux_proc_xfer_spu, linux_nat_xfer_osdata): Likewise.
* monitor.c (monitor_xfer_memory): Likewise.
(monitor_xfer_partial): Likewise.
* procfs.c (procfs_xfer_partial): Likewise.
* record-btrace.c (record_btrace_xfer_partial): Likewise.
* record-full.c (record_full_xfer_partial): Likewise.
(record_full_core_xfer_partial): Likewise.
* remote-sim.c (gdbsim_xfer_memory): Likewise.
(gdbsim_xfer_partial): Likewise.
* remote.c (remote_write_bytes_aux): Likewise. All callers
updated.
(remote_write_bytes, remote_read_bytes): Likewise. All
callers updated.
(remote_flash_erase): Likewise. All callers updated.
(remote_write_qxfer): Likewise. All callers updated.
(remote_read_qxfer): Likewise. All callers updated.
(remote_xfer_partial): Likewise.
* rs6000-nat.c (rs6000_xfer_partial): Likewise.
(rs6000_xfer_shared_libraries): Likewise.
* sol-thread.c (sol_thread_xfer_partial): Likewise.
(sol_thread_xfer_partial): Likewise.
* sparc-nat.c (sparc_xfer_wcookie): Likewise.
(sparc_xfer_partial): Likewise.
* spu-linux-nat.c (spu_proc_xfer_spu): Likewise. All callers
updated.
(spu_xfer_partial): Likewise.
* spu-multiarch.c (spu_xfer_partial): Likewise.
* tracepoint.c (tfile_xfer_partial): Likewise.
* windows-nat.c (windows_xfer_memory): Likewise.
(windows_xfer_shared_libraries): Likewise.
(windows_xfer_partial): Likewise.
* valprint.c: Replace 'target_xfer_error' with
'target_xfer_status' in comments.
Read branch trace data incrementally and extend the current trace rather than
discarding it and reading the entire trace buffer each time.
If the branch trace buffer overflowed, we can't extend the current trace so we
discard it and start anew by reading the entire branch trace buffer.
2014-01-16 Markus Metzger <markus.t.metzger@intel.com>
* common/linux-btrace.c (perf_event_read_bts, linux_read_btrace):
Support delta reads.
(linux_disable_btrace): Change return type.
* common/linux-btrace.h (linux_read_btrace): Change parameters
and return type to allow error reporting. Update users.
(linux_disable_btrace): Change return type. Update users.
* common/btrace-common.h (btrace_read_type) <BTRACE_READ_DELTA>:
New.
(btrace_error): New.
(btrace_block) <begin>: Comment on BEGIN == 0.
* btrace.c (btrace_compute_ftrace): Start from the end of
the current trace.
(btrace_stitch_trace, btrace_clear_history): New.
(btrace_fetch): Read delta trace, return if replaying.
(btrace_clear): Move clear history code to btrace_clear_history.
(parse_xml_btrace): Throw an error if parsing failed.
* target.h (struct target_ops) <to_read_btrace>: Change parameters
and return type to allow error reporting.
(target_read_btrace): Change parameters and return type to allow
error reporting.
* target.c (target_read_btrace): Update.
* remote.c (remote_read_btrace): Support delta reads. Pass
errors on.
* NEWS: Announce it.
gdbserver/
* target.h (target_ops) <read_btrace>: Change parameters and
return type to allow error reporting.
* server.c (handle_qxfer_btrace): Support delta reads. Pass
trace reading errors on.
* linux-low.c (linux_low_read_btrace): Pass trace reading
errors on.
(linux_low_disable_btrace): New.
Allow targets to supply their own target-specific frame unwinders; one for
normal frames and one for tailcall frames. If a target-specific unwinder
is supplied, it will be chosen before any other unwinder.
The original patch has been split into this and the next two patches.
gdb/
2013-02-11 Jan Kratochvil <jan.kratochvil@redhat.com>
* frame-unwind.c: Include target.h.
(frame_unwind_try_unwinder): New function with code from ...
(frame_unwind_find_by_frame): ... here. New variable
unwinder_from_target, call also target_get_unwinder)
(target_get_tailcall_unwinder, and frame_unwind_try_unwinder for it.
* target.c (target_get_unwinder, target_get_tailcall_unwinder): New.
* target.h (struct target_ops): New fields to_get_unwinder and
to_get_tailcall_unwinder.
(target_get_unwinder, target_get_tailcall_unwinder): New declarations.
The "record function-call-history" and "record instruction-history" commands
accept a range "begin, end". End is not included in both cases. Include it.
2014-01-16 Markus Metzger <markus.t.metzger@intel.com>
* record-btrace.c (record_btrace_insn_history_range): Include
end.
(record_btrace_insn_history_from): Adjust range.
(record_btrace_call_history_range): Include
end.
(record_btrace_call_history_from): Adjust range.
* NEWS: Announce changes.
testsuite/
* gdb.btrace/function_call_history.exp: Update tests.
* gdb.btrace/instruction_history.exp: Update tests.
doc/
* gdb.texinfo (Process Record and Replay): Update documentation.
This introduces async_callback_ftype. This is needed for
make-target-delegates to work properly, as it doesn't implement a real
parser. I think it's also an ok cleanup in its own right.
2014-01-15 Tom Tromey <tromey@redhat.com>
* target.h (async_callback_ftype): New typedef.
(struct target_ops) <to_async>: Use it.
Although we can tell upfront whether a remote target supports target
side commands, we can only tell whether the target supports that in
combination with a given breakpoint kind (software, hardware,
watchpoints, etc.) when we go and try to insert such a breakpoint kind
the first time. It's not desirable to make remote_insert_breakpoint
simply return -1 in this case, because if the breakpoint was set in a
shared library, insert_bp_location will assume that the breakpoint
insertion failed because the library wasn't mapped in.
insert_bp_location already handles errors/exceptions thrown from the
target_insert_xxx methods, exactly so the backend can tell the user
the detailed reason the insertion of hw breakpoints failed. But, in
the case of software breakpoints, it discards the detailed error
message.
So the patch makes insert_bp_location use the error's message for SW
breakpoints too, and, introduces a NOT_SUPPORTED_ERROR error code so
that insert_bp_location doesn't confuse the error for failure due to a
shared library disappearing.
The result is:
(gdb) c
Warning:
Cannot insert breakpoint 2: Target doesn't support breakpoints that have target side commands.
2014-01-09 Pedro Alves <palves@redhat.com>
Hui Zhu <hui@codesourcery.com>
PR gdb/16101
* breakpoint.c (insert_bp_location): Rename hw_bp_err_string to
bp_err_string. Don't mark the location shlib_disabled if the
error thrown wasn't a generic or memory error. Catch errors
thrown while inserting breakpoints in overlayed code. Output
error message of software breakpoints.
* remote.c (remote_insert_breakpoint): If this breakpoint has
target-side commands but this stub doesn't support Z0 packets,
throw NOT_SUPPORTED_ERROR error.
* exceptions.h (enum errors) <NOT_SUPPORTED_ERROR>: New error.
* target.h (target_insert_breakpoint): Extend comment.
(target_insert_hw_breakpoint): Add comment.
This patch adds a typedef target_xfer_partial_ftype. When we change
the signature of xfer_partial functions (for example, adding a new
parameter), we don't have to modify all of their declarations.
This patch also updates the type of parameters of target_xfer_partial
from "void *" to "gdb_byte *".
gdb:
2013-12-18 Yao Qi <yao@codesourcery.com>
* target.h (target_xfer_partial_ftype): New typedef.
(target_xfer_partial): Update declaration.
* auxv.h (memory_xfer_auxv): Likewise.
* ia64-hpux-nat.c (super_xfer_partial): Likewise.
* ia64-linux-nat.c (super_xfer_partial): Likewise.
* linux-nat.c (super_xfer_partial): Likewise.
* procfs.c (procfs_xfer_partial): Likewise.
* record-full.c (record_full_beneath_to_xfer_partial):
(tmp_to_xfer_partial): Likewise.
* sparc-nat.c (inf_ptrace_xfer_partial): Likewise.
* target.c (default_xfer_partial): Likewise.
(current_xfer_partial): Likewise.
(target_xfer_partial): Change parameter type to 'gdb_byte *'.
Similar to stack cache, in this patch, we add
TARGET_OBJECT_CODE_MEMORY to read code from target and add a new
option "set code-cache on|off" to optimize code accesses by
using the target memory cache.
In V4:
- Remove "without affecting correctness" from NEWS and doc.
- Replace "ON" with "on" in doc.
- "access" -> "accesses".
In V3:
- Rename functions and variables.
- Update command help, doc and NEWS entry.
- Invalidate cache on option transitions, to align with
the behaviour of "stack-cache". Since cache invalidation is
transparent to users, users don't know option "stack-cache"
transitions cause code cache invalidation.
V2 was reviewed by Doug. There are some changes in V3, so I post it
here.
gdb:
2013-11-24 Yao Qi <yao@codesourcery.com>
* NEWS: Add note on new "set code-cache" option.
* target-dcache.c (code_cache_enabled_1): New variable.
(code_cache_enabled): New variable.
(show_code_cache, set_code_cache): New function.
(code_cache_enabled_p): New function.
(_initialize_target_dcache): Register command.
* target-dcache.h (code_cache_enabled_p): Declare.
* target.c (memory_xfer_partial_1):Handle
TARGET_OBJECT_CODE_MEMORY and code_cache_enabled.
(target_read_code): New function.
* target.h (enum target_object) <TARGET_OBJECT_CODE_MEMORY>:
New.
(target_read_code): Declare.
gdb/doc:
2013-11-24 Yao Qi <yao@codesourcery.com>
* gdb.texinfo (Caching Remote Data): Document new
"set/show stack-cache" option.
This patch constifies the target_ops method to_detach.
This is a small cleanup, but also, I think, a bug-prevention fix,
since gdb already acts as if the "args" argument here was const.
In particular, top.c:quit_force calls kill_or_detach via
iterate_over_inferiors. kill_or_detach calls target_detach, passing
the same argument each time. So, if one of these methods was not
const-correct, then kill_or_detach would change its behavior in a
strange way.
I could not build every target I modified in this patch. I've
inspected them all by hand, though. Many targets do not use the
"args" parameter; a couple pass it to atoi; and a few pass it on to
the to_detach method of the target beneath. The only code that
required a real change was in linux-nat.c, and that only needed the
introduction of a temporary variable for const-correctness.
2013-11-08 Tom Tromey <tromey@redhat.com>
* aix-thread.c (aix_thread_detach): Update.
* corelow.c (core_detach): Update.
* darwin-nat.c (darwin_detach): Update.
* dec-thread.c (dec_thread_detach): Update.
* gnu-nat.c (gnu_detach): Update.
* go32-nat.c (go32_detach): Update.
* inf-ptrace.c (inf_ptrace_detach): Update.
* inf-ttrace.c (inf_ttrace_detach): Update.
* linux-fork.c (linux_fork_detach): Update.
* linux-fork.h (linux_fork_detach): Update.
* linux-nat.c (linux_nat_detach): Update. Introduce "tem"
local for const-correctness.
* linux-thread-db.c (thread_db_detach): Update.
* monitor.c (monitor_detach): Update.
* nto-procfs.c (procfs_detach): Update.
* procfs.c (procfs_detach): Update.
* record.c (record_detach): Update.
* record.h (record_detach): Update.
* remote-m32r-sdi.c (m32r_detach): Update.
* remote-mips.c (mips_detach): Update.
* remote-sim.c (gdbsim_detach): Update.
* remote.c (remote_detach_1, remote_detach)
(extended_remote_detach): Update.
* sol-thread.c (sol_thread_detach): Update.
* target.c (target_detach): Make "args" const.
(init_dummy_target): Update.
* target.h (struct target_ops) <to_detach>: Make argument const.
(target_detach): Likewise.
* windows-nat.c (windows_detach): Update.
target_read_memory & friends build on top of target_read (thus on top
of the target_xfer machinery), but turn all errors to EIO, an errno
value. I think we'd better convert all these to return a
target_xfer_error too, like target_xfer_partial in a previous patch.
The patch starts by doing that.
(The patch does not add a enum target_xfer_error value for '0'/no
error, and likewise does not change the return type of several of
these functions to enum target_xfer_error, because different functions
return '0' with different semantics.)
I audited the tree for memory_error calls, EIO checks, places where
GDB hardcodes 'errno = EIO', and also for strerror calls. What I
found is that nowadays there's really no need to handle random errno
values, other than the EIOs gdb itself hardcodes. No doubt errno
values would appear in common code back in the day when
target_xfer_memory was the main interface to access memory, but
nowadays, any errno value that deprecated interface could return is
just absorved by default_xfer_partial:
else if (xfered == 0 && errno == 0)
/* "deprecated_xfer_memory" uses 0, cross checked against
ERRNO as one indication of an error. */
return 0;
else
return -1;
There are two places in the code that check for EIO and print "out of
bounds", and defer to strerror for other errors. That's
c-lang.c:c_get_string, and valprint.c.:val_print_string. AFAICT, the
strerror branch can never be reached nowadays, as the only error
possible to get at those points is EIO, given that it's GDB itself
that set that errno value (in target_read_memory, etc.).
breakpoint.c:insert_bp_location always prints the error val as if an
errno, returned by target_insert_breakpoint, with strerr. Now the
error here is either always EIO for mem-break.c targets (again
hardcoded by the target_read_memory/target_write_memory functions), so
this always prints "Input/output error" or similar (depending on
host), or, for remote targets (and probably others), this gem:
Error accessing memory address 0x80200400: Unknown error -1.
This patch makes these 3 places print the exact same error
memory_error prints. This changes output, but I think this is better,
for making memory error output consistent with other commands, and, it
means we have a central place to tweak for memory errors.
E.g., this changes:
Cannot insert breakpoint 1.
Error accessing memory address 0x5fc660: Input/output error.
to:
Cannot insert breakpoint 1.
Cannot access memory at address 0x5fc660
Which I find pretty much acceptable.
Surprisingly, only py-prettyprint.exp had a regression, for needing an
adjustment. I also grepped the testsuite for the old errors, and
found no other hits.
Now that errno values aren't used anywhere in any of these memory
access related routines, I made memory_error itself take a
target_xfer_error instead of an errno. The new
target_xfer_memory_error function added recently is no longer
necessary, and is thus removed.
Tested on x86_64 Fedora 17, native and gdbserver.
gdb/
2013-10-09 Pedro Alves <palves@redhat.com>
* breakpoint.c (insert_bp_location): Use memory_error_message to
build the memory error string.
* c-lang.c: Include "gdbcore.h".
(c_get_string): Use memory_error to throw error.
(target_xfer_memory_error): Delete.
(memory_error_message): New, factored out from
target_xfer_memory_error.
(memory_error): Change parameter type to target_xfer_error.
Rewrite.
(read_memory): Use memory_error instead of
target_xfer_memory_error.
* gdbcore.h: Include "target.h".
(memory_error): Change parameter type to target_xfer_error.
(memory_error_message): Declare function.
* target.c (target_read_memory, target_read_stack)
(target_write_memory, target_write_raw_memory): Return
TARGET_XFER_E_IO on error. Adjust comments.
(get_target_memory): Pass TARGET_XFER_E_IO to memory_error,
instead of EIO.
* target.h (target_read, target_insert_breakpoint)
(target_remove_breakpoint): Adjust comments.
* valprint.c (partial_memory_read): Rename parameter, and adjust
comment.
(val_print_string): Use memory_error_message to build the memory
error string.
gdb/testsuite/
2013-10-09 Pedro Alves <palves@redhat.com>
* gdb.python/py-prettyprint.exp (run_lang_tests): Adjust expected
output.
detach_fork.
* inf-ptrace.c (inf_ptrace_follow_fork): Likewise.
* inf-ttrace.c (inf_ttrace_follow_fork): Likewise.
* inferior.h (detach_fork): Remove.
* infrun.c (detach_fork): Adjust comment and make it
static.
(follow_fork): Pass detach_fork parameter to
target_follow_fork.
* linux-nat.c (linux_child_follow_fork): New parameter
detach_fork.
* target.c (target_follow_fork): New parameter detach_fork.
Pass detach_fork as parameter and print its value.
* target.h (struct target_ops) <to_follow_fork>: New int
parameter.
(target_follow_fork): New parameter detach_fork.
In entry-values.exp, we have a test where the entry value of 'j' is
unavailable, so it is expected that printing j@entry yields
"<unavailable>". However, the actual output is:
(gdb) frame
#0 0x0000000000400540 in foo (i=0, i@entry=2, j=2, j@entry=<error reading variable: Cannot access memory at address 0x6009e8>)
The error is thrown here:
#0 throw_it (reason=RETURN_ERROR, error=MEMORY_ERROR, fmt=0x8cd550 "Cannot access memory at address %s", ap=0x7fffffffc8e8) at ../../src/gdb/exceptions.c:373
#1 0x00000000005e2f9c in throw_error (error=MEMORY_ERROR, fmt=0x8cd550 "Cannot access memory at address %s") at ../../src/gdb/exceptions.c:422
#2 0x0000000000673a5f in memory_error (status=5, memaddr=6293992) at ../../src/gdb/corefile.c:204
#3 0x0000000000673aea in read_memory (memaddr=6293992, myaddr=0x7fffffffca60 "\200\316\377\377\377\177", len=4) at ../../src/gdb/corefile.c:223
#4 0x00000000006784d1 in dwarf_expr_read_mem (baton=0x7fffffffcd50, buf=0x7fffffffca60 "\200\316\377\377\377\177", addr=6293992, len=4) at ../../src/gdb/dwarf2loc.c:334
#5 0x000000000067645e in execute_stack_op (ctx=0x1409480, op_ptr=0x7fffffffce87 "\237<\005@", op_end=0x7fffffffce88 "<\005@") at ../../src/gdb/dwarf2expr.c:1045
#6 0x0000000000674e29 in dwarf_expr_eval (ctx=0x1409480, addr=0x7fffffffce80 "\003\350\t`", len=8) at ../../src/gdb/dwarf2expr.c:364
#7 0x000000000067c5b2 in dwarf2_evaluate_loc_desc_full (type=0x10876d0, frame=0xd8ecc0, data=0x7fffffffce80 "\003\350\t`", size=8, per_cu=0xf24c40, byte_offset=0)
at ../../src/gdb/dwarf2loc.c:2236
#8 0x000000000067cc65 in dwarf2_evaluate_loc_desc (type=0x10876d0, frame=0xd8ecc0, data=0x7fffffffce80 "\003\350\t`", size=8, per_cu=0xf24c40)
at ../../src/gdb/dwarf2loc.c:2407
#9 0x000000000067a5d4 in dwarf_entry_parameter_to_value (parameter=0x13a7960, deref_size=18446744073709551615, type=0x10876d0, caller_frame=0xd8ecc0, per_cu=0xf24c40)
at ../../src/gdb/dwarf2loc.c:1160
#10 0x000000000067a962 in value_of_dwarf_reg_entry (type=0x10876d0, frame=0xd8de70, kind=CALL_SITE_PARAMETER_DWARF_REG, kind_u=...) at ../../src/gdb/dwarf2loc.c:1310
#11 0x000000000067aaca in value_of_dwarf_block_entry (type=0x10876d0, frame=0xd8de70, block=0xf1c2d4 "Q", block_len=1) at ../../src/gdb/dwarf2loc.c:1363
#12 0x000000000067e7c9 in locexpr_read_variable_at_entry (symbol=0x13a7540, frame=0xd8de70) at ../../src/gdb/dwarf2loc.c:3326
#13 0x00000000005daab6 in read_frame_arg (sym=0x13a7540, frame=0xd8de70, argp=0x7fffffffd0e0, entryargp=0x7fffffffd100) at ../../src/gdb/stack.c:362
#14 0x00000000005db384 in print_frame_args (func=0x13a7470, frame=0xd8de70, num=-1, stream=0xea3890) at ../../src/gdb/stack.c:669
#15 0x00000000005dc338 in print_frame (frame=0xd8de70, print_level=1, print_what=SRC_AND_LOC, print_args=1, sal=...) at ../../src/gdb/stack.c:1199
#16 0x00000000005db8ee in print_frame_info (frame=0xd8de70, print_level=1, print_what=SRC_AND_LOC, print_args=1) at ../../src/gdb/stack.c:851
#17 0x00000000005da2bb in print_stack_frame (frame=0xd8de70, print_level=1, print_what=SRC_AND_LOC) at ../../src/gdb/stack.c:169
#18 0x00000000005de236 in frame_command (level_exp=0x0, from_tty=1) at ../../src/gdb/stack.c:2265
dwarf2_evaluate_loc_desc_full (frame #7) knows to handle
NOT_AVAILABLE_ERROR errors, but read_memory always throws
a generic error.
Presently, only the value machinery knows to handle unavailable
memory. We need to push the awareness down to the target_xfer layer,
making it return a finer grained error indication. We can only return
a generic -1 nowadays, which leaves the upper layers with no clue on
why the xfer failed. Use target_xfer_partial directly, rather than
propagating the error through target_read_memory so as to get a better
address to display in the error message.
(target_read_memory & friends build on top of target_read (thus the
target_xfer machinery), but turn all errors to EIO, an errno value. I
think this is a mistake, and we'd better convert all these to return a
target_xfer_error too, but that can be done separately. I looked
around a bit over memory_error calls, and the need to handle random
errno values, other than the EIOs gdb itself hardcodes, probably comes
(only) from deprecated_xfer_memory, which uses errno for error
indication, but I didn't look exhaustively. We should really get rid
of deprecated_xfer_memory and of passing down errno values as error
indication in target_read & friends methods).
Tested on x86_64 Fedora 17, native and gdbserver. Fixes the test in
the PR, which will be added to the testsuite later.
gdb/
2013-08-22 Pedro Alves <palves@redhat.com>
PR gdb/15871
* corefile.c (target_xfer_memory_error): New function.
(memory_error): Defer EIO to target_memory_error.
(read_memory): Use target_xfer_partial, and handle finer-grained
target xfer errors.
* target.c (target_xfer_error_to_string): New function.
(memory_xfer_partial_1): If memory is known to be
unavailable, return TARGET_XFER_E_UNAVAILABLE instead of -1.
(target_xfer_partial): Make extern.
* target.h (enum target_xfer_error): New enum.
(target_xfer_error_to_string): Declare function.
(target_xfer_partial): Declare function.
(struct target_ops) <xfer_partial>: Adjust describing comment.
* Makefile.in (SFILES): Remove common/target-common.c and
add target/waitstatus.c.
(HFILES_NO_SRCDIR): Remove common/target-common.h and add
target/resume.h, target/wait.h and target/waitstatus.h.
(COMMON_OBS): Remove target-common.o and add
waitstatus.o.
(target-common.o): Remove.
(waitstatus.o): New target object file.
* common/target-common.c: Move contents to
target/waitstatus.c and remove.
* common/target-common.h: Move contents to other files and
remove.
(enum resume_kind: Move to target/resume.h.
(TARGET_WNOHANG): Move to target/wait.h.
(enum target_waitkind): Move to target/waitstatus.h.
(struct target_waitstatus): Likewise.
* target.h: Do not include target-common.h and
include target/resume.h, target/wait.h and
target/waitstatus.h.
* target/resume.h: New file.
* target/wait.h: New file.
* target/waitstatus.h: New file.
* target/waitstatus.c: New file.
gdb/gdbserver/
* Makefile.in (INCLUDE_CFLAGS): Include -I$(srcdir)/../.
(SFILES): Remove $(srcdir)/common/target-common.c and
add $(srcdir)/target/waitstatus.c.
(OBS): Remove target-common.o and add waitstatus.o.
(server_h): Remove $(srcdir)/../common/target-common.h and
add $(srcdir)/../target/resume.h, $(srcdir)/../target/wait.h
and $(srcdir)/../target/waitstatus.h.
(target-common.o): Remove.
(waitstatus.o): New target object file.
* target.h: Do not include target-common.h and
include target/resume.h, target/wait.h and
target/waitstatus.h.
This patch fixes the target double-close problem (PR remote/15266),
and in the process removes pop_target entire (PR remote/15256).
The first issue is that pop_target calls target_close. However, it
then calls unpush_target, which also calls target_close. This means
targets must be able to be closed twice. Not only is this strange,
but it also directly contradicts the contract of to_xclose targets.
(We currently have just a single such target, and it is never pushed;
but I plan to add more, and so this latent bug is triggered.)
The second issue is that it seems to me that calling pop_target is
often unsafe. This is what cropped up in 15256, where the remote
target assumed that it could pop_target -- but there was another
target higher on the stack, leading to confusion.
But, it is always just as easy to call unpush_target as it is to call
pop_target; and it is also safer. So, removing pop_target seemed like
an improvement.
Finally, this adds an assertion to target_close to ensure that no
currently-pushed target can be closed.
Built and regtested on x86-64 Fedora 18; both natively and using the
native-gdbserver board file.
PR remote/15256, PR remote/15266:
* bfd-target.c (target_bfd_reopen): Initialize to_magic.
* monitor.c (monitor_detach): Use unpush_target.
* remote-m32r-sdi.c (m32r_detach): Use unpush_target.
* remote-mips.c (mips_detach): Use unpush_target. Don't
call mips_close.
* remote-sim.c (gdbsim_detach): Use unpush_target.
* target.c (pop_target): Remove.
(pop_all_targets_above): Don't call target_close.
(target_close): Assert that the target is unpushed.
* target.h (pop_target): Don't declare.
* tracepoint.c (tfile_open): Use unpush_target.
Right now, "help target" will include this line:
target multi-thread -- Threads and pthreads support
However, it doesn't make sense to invoke "target multi-thread".
This patch fixes the problem by not registering the multi-thread
target. add_target does some needed initialization of the target_ops,
so I broke this out into a new function.
It isn't clear to me whether this patch requires a test case or not.
I'm not sure whether there are other unregistered targets; but if
there are, it seems unlikely that we test for their absence from the
help.
Built and regtested on x86-64 Fedora 18.
* linux-thread-db.c (init_thread_db_ops): Call
complete_target_initialization.
(_initialize_thread_db): Don't call add_target.
* target.c (complete_target_initialization): New function.
(add_target_with_completer): Call it.
* target.h (complete_target_initialization): Declare.
