[libvirt] [PATCH] dnsmasq: Fix errno handling and don't unlink non-existing files

[Daniel Veillard]

On Wed, Jun 29, 2011 at 02:14:19AM +0200, Matthias Bolte wrote:
> addnhostsSave and hostsfileSave expect < 0 return value on error from
> addnhostsWrite and hostsfileWrite but then pass err instead of -err
> to virReportSystemError that expects an errno value.
> 
> Also addnhostsWrite returns -ENOMEM and errno, change this to -errno.
> 
> addnhostsWrite and hostsfileWrite tried to unlink the tempfile after
> renaming it, making both fail on the final step. Remove the unnecessary
> unlink calls.
> ---
>  src/util/dnsmasq.c |   44 +++++++++++++++-----------------------------
>  1 files changed, 15 insertions(+), 29 deletions(-)
> 
> diff --git a/src/util/dnsmasq.c b/src/util/dnsmasq.c
> index 5baa34f..aadca10 100644
> --- a/src/util/dnsmasq.c
> +++ b/src/util/dnsmasq.c
> @@ -185,14 +185,14 @@ addnhostsWrite(const char *path,
>      if (!(f = fopen(tmp, "w"))) {
>          istmp = false;
>          if (!(f = fopen(path, "w"))) {
> -            rc = errno;
> +            rc = -errno;
>              goto cleanup;
>          }
>      }
>  
>      for (i = 0; i < nhosts; i++) {
>          if (fputs(hosts[i].ip, f) == EOF || fputc('\t', f) == EOF) {
> -            rc = errno;
> +            rc = -errno;
>              VIR_FORCE_FCLOSE(f);
>  
>              if (istmp)
> @@ -203,7 +203,7 @@ addnhostsWrite(const char *path,
>  
>          for (ii = 0; ii < hosts[i].nhostnames; ii++) {
>              if (fputs(hosts[i].hostnames[ii], f) == EOF || fputc('\t', f) == EOF) {
> -                rc = errno;
> +                rc = -errno;
>                  VIR_FORCE_FCLOSE(f);
>  
>                  if (istmp)
> @@ -214,7 +214,7 @@ addnhostsWrite(const char *path,
>          }
>  
>          if (fputc('\n', f) == EOF) {
> -            rc = errno;
> +            rc = -errno;
>              VIR_FORCE_FCLOSE(f);
>  
>              if (istmp)
> @@ -225,21 +225,14 @@ addnhostsWrite(const char *path,
>      }
>  
>      if (VIR_FCLOSE(f) == EOF) {
> -        rc = errno;
> +        rc = -errno;
>          goto cleanup;
>      }
>  
> -    if (istmp) {
> -        if (rename(tmp, path) < 0) {
> -            rc = errno;
> -            unlink(tmp);
> -            goto cleanup;
> -        }
> -
> -        if (unlink(tmp) < 0) {
> -            rc = errno;
> -            goto cleanup;
> -        }
> +    if (istmp && rename(tmp, path) < 0) {
> +        rc = -errno;
> +        unlink(tmp);
> +        goto cleanup;
>      }
>  
>   cleanup:
> @@ -255,7 +248,7 @@ addnhostsSave(dnsmasqAddnHostsfile *addnhostsfile)
>                               addnhostsfile->nhosts);
>  
>      if (err < 0) {
> -        virReportSystemError(err, _("cannot write config file '%s'"),
> +        virReportSystemError(-err, _("cannot write config file '%s'"),
>                               addnhostsfile->path);
>          return -1;
>      }
> @@ -402,17 +395,10 @@ hostsfileWrite(const char *path,
>          goto cleanup;
>      }
>  
> -    if (istmp) {
> -        if (rename(tmp, path) < 0) {
> -            rc = -errno;
> -            unlink(tmp);
> -            goto cleanup;
> -        }
> -
> -        if (unlink(tmp) < 0) {
> -            rc = -errno;
> -            goto cleanup;
> -        }
> +    if (istmp && rename(tmp, path) < 0) {
> +        rc = -errno;
> +        unlink(tmp);
> +        goto cleanup;
>      }
>  
>   cleanup:
> @@ -428,7 +414,7 @@ hostsfileSave(dnsmasqHostsfile *hostsfile)
>                               hostsfile->nhosts);
>  
>      if (err < 0) {
> -        virReportSystemError(err, _("cannot write config file '%s'"),
> +        virReportSystemError(-err, _("cannot write config file '%s'"),
>                               hostsfile->path);
>          return -1;
>      }

  ACK,

Daniel

-- 
Daniel Veillard      | libxml Gnome XML XSLT toolkit  http://xmlsoft.org/
daniel at veillard.com  | Rpmfind RPM search engine http://rpmfind.net/
http://veillard.com/ | virtualization library  http://libvirt.org/