Re: [PATCH 2/6] dump/win_dump: Improve error messages on write error

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 13/5/24 16:48, Markus Armbruster wrote:
> Philippe Mathieu-Daudé <philmd@linaro.org> writes:
> 
>> On 13/5/24 16:16, Markus Armbruster wrote:
>>> create_win_dump() and write_run report qemu_write_full() failure to
>>> their callers as
>>>       An IO error has occurred
>>> The errno set by qemu_write_full() is lost.
>>> Improve this to
>>>       win-dump: failed to write header: <description of errno>
>>> and
>>>       win-dump: failed to save memory: <description of errno>
>>> This matches how dump.c reports similar errors.
>>> Signed-off-by: Markus Armbruster <armbru@redhat.com>
>>> ---
>>>    dump/win_dump.c | 7 ++++---
>>>    1 file changed, 4 insertions(+), 3 deletions(-)
>>> diff --git a/dump/win_dump.c b/dump/win_dump.c
>>> index b7bfaff379..0e4fe692ce 100644
>>> --- a/dump/win_dump.c
>>> +++ b/dump/win_dump.c
>>> @@ -12,7 +12,6 @@
>>>    #include "sysemu/dump.h"
>>>    #include "qapi/error.h"
>>>    #include "qemu/error-report.h"
>>> -#include "qapi/qmp/qerror.h"
>>>    #include "exec/cpu-defs.h"
>>>    #include "hw/core/cpu.h"
>>>    #include "qemu/win_dump_defs.h"
>>> @@ -52,6 +51,7 @@ static size_t write_run(uint64_t base_page, uint64_t page_count,
>>>        uint64_t addr = base_page << TARGET_PAGE_BITS;
>>>        uint64_t size = page_count << TARGET_PAGE_BITS;
>>>        uint64_t len, l;
>>> +    int eno;
>>>        size_t total = 0;
>>>          while (size) {
>>> @@ -65,9 +65,10 @@ static size_t write_run(uint64_t base_page, uint64_t page_count,
>>>            }
>>>              l = qemu_write_full(fd, buf, len);
>>> +        eno = errno;
>>
>> Hmm this show the qemu_write_full() API isn't ideal.
>> Maybe we could pass &l as argument and return errno.
>> There are only 20 calls.
> 
> qemu_write_full() is a drop-in replacement for write().

Fine.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>