Re: [PATCH v5 5/8] util: add Error object for qemu_open_internal error reporting

[Markus Armbruster]

Daniel P. Berrangé <berrange@redhat.com> writes:

> Instead of relying on the limited information from errno, we can now
> also provide detailed error messages to callers that ask for it.
>
> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
> ---
>  util/osdep.c | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/util/osdep.c b/util/osdep.c
> index dd34b58bb7..28aa89adc9 100644
> --- a/util/osdep.c
> +++ b/util/osdep.c
> @@ -298,7 +298,7 @@ static int qemu_open_cloexec(const char *name, int flags, 
> mode_t mode)
>   * Opens a file with FD_CLOEXEC set
>   */
>  static int
> -qemu_open_internal(const char *name, int flags, mode_t mode)
> +qemu_open_internal(const char *name, int flags, mode_t mode, Error **errp)
>  {
>      int ret;
>  
> @@ -312,12 +312,15 @@ qemu_open_internal(const char *name, int flags, mode_t 
> mode)
>  
>          fdset_id = qemu_parse_fdset(fdset_id_str);
>          if (fdset_id == -1) {
> +            error_setg(errp, "Could not parse fdset %s", name);
>              errno = EINVAL;
>              return -1;
>          }
>  
>          dupfd = monitor_fdset_dup_fd_add(fdset_id, flags);
>          if (dupfd == -1) {
> +            error_setg_errno(errp, errno, "Could not dup FD for %s flags %x",
> +                             name, flags);

You kept the reporting of flags here.  Intentional?

>              return -1;
>          }
>  
> @@ -327,6 +330,13 @@ qemu_open_internal(const char *name, int flags, mode_t 
> mode)
>  
>      ret = qemu_open_cloexec(name, flags, mode);
>  
> +    if (ret == -1) {
> +        const char *action = flags & O_CREAT ? "create" : "open";
> +        error_setg_errno(errp, errno, "Could not %s '%s'",
> +                         action, name);
> +    }
> +
> +
>      return ret;
>  }

Much neater.  Thanks!

>  
> @@ -343,7 +353,7 @@ int qemu_open_old(const char *name, int flags, ...)
>      }
>      va_end(ap);
>  
> -    ret = qemu_open_internal(name, flags, mode);
> +    ret = qemu_open_internal(name, flags, mode, NULL);
>  
>  #ifdef O_DIRECT
>      if (ret == -1 && errno == EINVAL && (flags & O_DIRECT)) {

Reviewed-by: Markus Armbruster <armbru@redhat.com>