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Pedro Alves 578d3588ee Stop using errno values around target_xfer interfaces and memory errors.
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.
2013-10-09 17:00:00 +00:00
bfd PR binutils/16022 2013-10-09 16:24:43 +00:00
binutils Fix typo in previous delta. 2013-10-09 16:37:44 +00:00
config 2013-04-30 Jan-Benedict Glaw <jbglaw@lug-owl.de> 2013-04-30 12:40:42 +00:00
cpu PR binutils/15241 2013-03-08 17:25:12 +00:00
elfcpp elfcpp/ 2013-03-01 22:45:56 +00:00
etc
gas PR gas/16025 2013-10-09 16:10:11 +00:00
gdb Stop using errno values around target_xfer interfaces and memory errors. 2013-10-09 17:00:00 +00:00
gold gold/ 2013-10-07 17:08:34 +00:00
gprof PR gprof/16027 2013-10-09 16:34:30 +00:00
include 2013-09-17 Doug Gilmore <Doug.Gilmore@imgtec.com> 2013-09-17 21:05:49 +00:00
intl
ld PR ld/16028 2013-10-09 16:30:02 +00:00
libdecnumber merge from gcc 2013-07-09 16:04:44 +00:00
libiberty merge from gcc 2013-09-12 16:08:09 +00:00
opcodes opcodes/ 2013-10-08 15:12:59 +00:00
readline * readline.c (bind_arrow_keys_internal): 2013-09-24 14:49:48 +00:00
sim Regenerate sim configure files to pick up support for powerpc64le in 2013-09-23 00:32:27 +00:00
texinfo
.cvsignore
.gitignore Sync the root .gitignore file with GCC's. 2013-01-11 15:17:35 +00:00
ChangeLog 2013-10-08 Jan-Benedict Glaw <jbglaw@lug-owl.de> 2013-10-08 14:14:12 +00:00
compile
config-ml.in
config.guess * config.guess: Update from config repo. 2013-04-29 15:13:53 +00:00
config.rpath
config.sub * config.guess: Update from config repo. 2013-04-29 15:13:53 +00:00
configure 2013-10-08 Jan-Benedict Glaw <jbglaw@lug-owl.de> 2013-10-08 14:14:12 +00:00
configure.ac 2013-10-08 Jan-Benedict Glaw <jbglaw@lug-owl.de> 2013-10-08 14:14:12 +00:00
COPYING
COPYING3
COPYING3.LIB
COPYING.LIB
COPYING.LIBGLOSS 2013-01-07 Jeff Johnston <jjohnstn@redhat.com> 2013-01-07 21:39:26 +00:00
COPYING.NEWLIB 2013-10-01 Jeff Johnston <jjohnstn@redhat.com> 2013-10-01 18:14:04 +00:00
depcomp
djunpack.bat
install-sh
libtool.m4 * libtool.m4 (_LT_ENABLE_LOCK <ld -m flags>): Remove non-canonical 2013-09-20 09:51:25 +00:00
lt~obsolete.m4
ltgcc.m4
ltmain.sh
ltoptions.m4
ltsugar.m4
ltversion.m4
MAINTAINERS
Makefile.def 2013-08-12 Jan-Benedict Glaw <jbglaw@lug-owl.de> 2013-08-12 11:36:35 +00:00
Makefile.in 2013-08-12 Jan-Benedict Glaw <jbglaw@lug-owl.de> 2013-08-12 11:36:35 +00:00
Makefile.tpl * Makefile.tpl (BOOT_ADAFLAGS): Remove -gnata. 2013-01-11 11:48:54 +00:00
makefile.vms
missing
mkdep
mkinstalldirs
move-if-change
README
README-maintainer-mode
setup.com
src-release src-release: Strip "-cvs" from GDB source dir and tarball. 2013-08-17 01:07:52 +00:00
symlink-tree
ylwrap

		   README for GNU development tools

This directory contains various GNU compilers, assemblers, linkers, 
debuggers, etc., plus their support routines, definitions, and documentation.

If you are receiving this as part of a GDB release, see the file gdb/README.
If with a binutils release, see binutils/README;  if with a libg++ release,
see libg++/README, etc.  That'll give you info about this
package -- supported targets, how to use it, how to report bugs, etc.

It is now possible to automatically configure and build a variety of
tools with one command.  To build all of the tools contained herein,
run the ``configure'' script here, e.g.:

	./configure 
	make

To install them (by default in /usr/local/bin, /usr/local/lib, etc),
then do:
	make install

(If the configure script can't determine your type of computer, give it
the name as an argument, for instance ``./configure sun4''.  You can
use the script ``config.sub'' to test whether a name is recognized; if
it is, config.sub translates it to a triplet specifying CPU, vendor,
and OS.)

If you have more than one compiler on your system, it is often best to
explicitly set CC in the environment before running configure, and to
also set CC when running make.  For example (assuming sh/bash/ksh):

	CC=gcc ./configure
	make

A similar example using csh:

	setenv CC gcc
	./configure
	make

Much of the code and documentation enclosed is copyright by
the Free Software Foundation, Inc.  See the file COPYING or
COPYING.LIB in the various directories, for a description of the
GNU General Public License terms under which you can copy the files.

REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info
on where and how to report problems.