[libvirt] [PATCHv2 02/10] virsh: reduce complexity in argv iteration
This reduces things from O(n^2) to O(n).
* tools/virsh.c (vshCommandOptArgv): Change signature.
(cmdEcho): Update caller.
Based on a patch by Lai Jiangshan.
---
v2: Drop the macro, avoid __ naming, reduce patch size
tools/virsh.c | 21 ++++++++++++---------
1 files changed, 12 insertions(+), 9 deletions(-)
diff --git a/tools/virsh.c b/tools/virsh.c
index d2f4020..da975ba 100644
--- a/tools/virsh.c
+++ b/tools/virsh.c
@@ -280,7 +280,8 @@ static int vshCommandOptULongLong(const vshCmd *cmd, const char
*name,
unsigned long long *value)
ATTRIBUTE_NONNULL(3) ATTRIBUTE_RETURN_CHECK;
static bool vshCommandOptBool(const vshCmd *cmd, const char *name);
-static char *vshCommandOptArgv(const vshCmd *cmd, int count);
+static const vshCmdOpt *vshCommandOptArgv(const vshCmd *cmd,
+ const vshCmdOpt *opt);
#define VSH_BYID (1 << 1)
#define VSH_BYUUID (1 << 2)
@@ -10439,6 +10440,7 @@ cmdEcho (vshControl *ctl ATTRIBUTE_UNUSED, const vshCmd *cmd)
bool shell = false;
bool xml = false;
int count = 0;
+ const vshCmdOpt *opt = NULL;
char *arg;
virBuffer buf = VIR_BUFFER_INITIALIZER;
@@ -10447,10 +10449,11 @@ cmdEcho (vshControl *ctl ATTRIBUTE_UNUSED, const vshCmd *cmd)
if (vshCommandOptBool(cmd, "xml"))
xml = true;
- while ((arg = vshCommandOptArgv(cmd, count)) != NULL) {
+ while ((opt = vshCommandOptArgv(cmd, opt))) {
bool close_quote = false;
char *q;
+ arg = opt->data;
if (count)
virBufferAddChar(&buf, ' ');
/* Add outer '' only if arg included shell metacharacters. */
@@ -11904,20 +11907,20 @@ vshCommandOptBool(const vshCmd *cmd, const char *name)
}
/*
- * Returns the COUNT argv argument, or NULL after last argument.
+ * Returns the next argv argument after OPT (or the first one if OPT
+ * is NULL), or NULL if no more are present.
*
- * Requires that a VSH_OT_ARGV option with the name "" be last in the
+ * Requires that a VSH_OT_ARGV option be last in the
* list of supported options in CMD->def->opts.
*/
-static char *
-vshCommandOptArgv(const vshCmd *cmd, int count)
+static const vshCmdOpt *
+vshCommandOptArgv(const vshCmd *cmd, const vshCmdOpt *opt)
{
- vshCmdOpt *opt = cmd->opts;
+ opt = opt ? opt->next : cmd->opts;
while (opt) {
if (opt->def && opt->def->type == VSH_OT_ARGV) {
- if (count-- == 0)
- return opt->data;
+ return opt;
}
opt = opt->next;
}
--
1.7.4.4