Re: [libvirt] [PATCH 1/3] Re-factor qemu version parsing
On Wed, Jun 10, 2009 at 09:02:39PM +0100, Mark McLoughlin wrote:
This patch is purely re-factoring without any functional changes
to make way for the next patch.
The main thing achieved by the refactoring is that we now have
easier access to the parenthesised string that KVM folks seem
to delight in changing.
This kind of parsing looks more flexible to me, even if a bit
less readable than using pure sscanf
[...]
+#define QEMU_VERSION_STR "QEMU PC emulator version "
+#define KVM_VER_PREFIX " (kvm-"
+
+static int qemudParseHelpStr(const char *help,
+ unsigned int *flags,
+ unsigned int *version,
+ unsigned int *kvm_version)
+{
+ unsigned major, minor, micro;
+ const char *p = help;
+
+ *flags = *version = *kvm_version = 0;
+
+ if (!STRPREFIX(p, QEMU_VERSION_STR))
+ goto fail;
+
+ p += strlen(QEMU_VERSION_STR);
But I would not integate the spaces in the strings and instead
use a macro like
#define QEMU_VERSION_STR "QEMU PC emulator version"
#define SKIP_BLANKS(p) while ((*(p) == ' ') || (*(p) == '\t')) (p)++;
and here do SKIP_BLANKS(p)
+ major = virParseNumber(&p);
+ if (major == -1 || *p != '.')
+ goto fail;
+
+ ++p;
+
+ minor = virParseNumber(&p);
+ if (major == -1 || *p != '.')
+ goto fail;
+
+ ++p;
+
+ micro = virParseNumber(&p);
+ if (major == -1)
+ goto fail;
and SKIP_BLANKS(p) here
and
#define KVM_VER_PREFIX "(kvm-"
without the leading space.
+ if (STRPREFIX(p, KVM_VER_PREFIX)) {
+ int ret;
+
+ p += strlen(KVM_VER_PREFIX);
+
+ ret = virParseNumber(&p);
+ if (ret == -1)
+ goto fail;
+
+ *kvm_version = ret;
[...]
But I'm biased on parsing ... and that's not critical, ACK,
Daniel
--
Daniel Veillard | libxml Gnome XML XSLT toolkit http://xmlsoft.org/
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