Files
mesh-catalog/modules/kernel/cmd/kernel-tools/machine.go
T

66 lines
1.6 KiB
Go

package main
// The machine as the tools see it: the files they read, under a root that tests replace with a stand-in
// tree. Everything read here is readable by the runtime's account; nothing is escalated.
import (
"fmt"
"io/fs"
"os"
"path/filepath"
)
// Machine reads this machine's kernel files under Root ("/" on the machine).
type Machine struct {
Root string
}
// ThisMachine is the machine the runtime launched this bundle on.
func ThisMachine() *Machine { return &Machine{Root: "/"} }
func (m *Machine) path(p string) string { return filepath.Join(m.Root, p) }
func (m *Machine) read(p string) (string, error) {
b, err := os.ReadFile(m.path(p))
return string(b), err
}
func (m *Machine) dirs(p string) ([]string, error) {
entries, err := os.ReadDir(m.path(p))
if err != nil {
return nil, err
}
var out []string
for _, e := range entries {
if e.IsDir() || e.Type()&fs.ModeSymlink != 0 {
out = append(out, e.Name())
}
}
return out, nil
}
// whole is a whole-number argument with a default, kept within bounds.
func whole(args map[string]any, key string, def, least, most int) (int, error) {
raw, present := args[key]
if !present || raw == nil {
return def, nil
}
f, ok := raw.(float64)
if !ok || f != float64(int(f)) {
return 0, fmt.Errorf("%s must be a whole number", key)
}
n := int(f)
if n < least {
return 0, fmt.Errorf("%s must be at least %d", key, least)
}
if n > most {
n = most
}
return n, nil
}
// schema is a tool's input: its properties.
func schema(properties map[string]any) map[string]any {
return map[string]any{"type": "object", "properties": properties}
}