[libvirt] [PATCH] Look in /usr/libexec for the qemu-kvm binary.

[Daniel Veillard]

On Wed, Jan 27, 2010 at 09:23:50AM -0500, Chris Lalancette wrote:
> On RHEL-5 the qemu-kvm binary is located in /usr/libexec.
> To reduce confusion for people trying to run upstream libvirt
> on RHEL-5 machines, make the qemu driver look in /usr/libexec
> for the qemu-kvm binary.
> 
> To make this work, I modified virFindFileInPath to handle an
> absolute path correctly.  I also ran into an issue where
> NULL was sometimes being passed for the file parameter
> to virFindFileInPath; it didn't crash prior to this patch
> since it was building paths like /usr/bin/(null).  This
> is non-standard behavior, though, so I added a NULL
> check at the beginning.
> 
> Signed-off-by: Chris Lalancette <clalance at redhat.com>
> ---
>  src/qemu/qemu_conf.c |    3 ++-
>  src/util/util.c      |   13 +++++++++++++
>  2 files changed, 15 insertions(+), 1 deletions(-)
> 
> diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c
> index f4a6c08..d5e38c2 100644
> --- a/src/qemu/qemu_conf.c
> +++ b/src/qemu/qemu_conf.c
> @@ -804,7 +804,8 @@ qemudCapsInitGuest(virCapsPtr caps,
>      if (STREQ(info->arch, hostmachine) ||
>          (STREQ(hostmachine, "x86_64") && STREQ(info->arch, "i686"))) {
>          if (access("/dev/kvm", F_OK) == 0) {
> -            const char *const kvmbins[] = { "qemu-kvm", /* Fedora */
> +            const char *const kvmbins[] = { "/usr/libexec/qemu-kvm", /* RHEL */
> +                                            "qemu-kvm", /* Fedora */
>                                              "kvm" }; /* Upstream .spec */
>  
>              for (i = 0; i < ARRAY_CARDINALITY(kvmbins); ++i) {
> diff --git a/src/util/util.c b/src/util/util.c
> index 0ce5026..394ef35 100644
> --- a/src/util/util.c
> +++ b/src/util/util.c
> @@ -1114,6 +1114,19 @@ char *virFindFileInPath(const char *file)
>      char *pathseg;
>      char fullpath[PATH_MAX];
>  
> +    if (file == NULL)
> +        return NULL;
> +
> +    /* if we are passed an absolute path (starting with /), return a
> +     * copy of that path
> +     */
> +    if (file[0] == '/') {
> +        if (virFileExists(file))
> +            return strdup(file);
> +        else
> +            return NULL;
> +    }
> +
>      /* copy PATH env so we can tweak it */
>      if (virStrcpyStatic(pathenv, getenv("PATH")) == NULL)
>          return NULL;

  ACK, makes sense !

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/