code review 6211071: syscall: implement nametomib() on netbsd

syscall: implement nametomib() on netbsd

Implement nametomib() on NetBSD using the CTL_QUERY node discovery
mechanism.

[jsing, 2012-05-20 15:46:21]

Hello golang-dev@googlegroups.com,

I'd like you to review this change to
https://go.googlecode.com/hg/

[rsc, 2012-05-22 03:21:10]

LGTM

Looks good except that Rietveld won't show me side-by-side diffs, and also
this:

+	// Split name into components.
+	s := ""
+	parts := make([]string, 0)
+	for _, c := range name {
+		if c == '.' {
+			parts = append(parts, s)
+			s = ""
+		} else {
+			s = s + string(c)
+		}
+	}
+	parts = append(parts, s)

This code build strings with + one char at a time, which is gonig to
be quadratic.  You've already got a string in hand, so you can slice
it instead of building new strings:

var parts []string
last := 0
for i := 0; i < len(name); i++ {
    if c == '.' {
        parts = append(parts, name[last:i])
        last = i+1
    }
}
parts = append(parts, name[last:])

[jsing, 2012-05-22 15:30:15]

On 2012/05/22 03:21:10, rsc wrote:
> LGTM
> 
> Looks good except that Rietveld won't show me side-by-side diffs, and also
> this:
> 
> +	// Split name into components.
> +	s := ""
> +	parts := make([]string, 0)
> +	for _, c := range name {
> +		if c == '.' {
> +			parts = append(parts, s)
> +			s = ""
> +		} else {
> +			s = s + string(c)
> +		}
> +	}
> +	parts = append(parts, s)
> 
> This code build strings with + one char at a time, which is gonig to
> be quadratic.  You've already got a string in hand, so you can slice
> it instead of building new strings:
> 
> var parts []string
> last := 0
> for i := 0; i < len(name); i++ {
>     if c == '.' {
>         parts = append(parts, name[last:i])
>         last = i+1
>     }
> }
> parts = append(parts, name[last:])

Good point - done.

[jsing, 2012-05-22 15:34:00]

*** Submitted as http://code.google.com/p/go/source/detail?r=ff109fe72249 ***

syscall: implement nametomib() on netbsd

Implement nametomib() on NetBSD using the CTL_QUERY node discovery
mechanism.

R=golang-dev, rsc
CC=golang-dev
http://codereview.appspot.com/6211071