Count clipmenud when it runs as a bash script (issue 860)

modules/clipmenu/cmd/clipmenu-tools/clipboard_test.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"os"
 	"os/exec"
-	"os/user"
 	"path/filepath"
 	"strconv"
 	"strings"
@@ -227,26 +226,21 @@ func TestWithoutAStoreTheChangesSayWhy(t *testing.T) {
 	}
 }
 
-// The tools can run as another account than the operator's; the daemon that counts is the operator's
-// (issue 860). Here the operator is the test's own account and the tool runs as a different uid.
-func TestCollectingIsTheOperatorsDaemonNotThatOfTheAccountTheToolRunsAs(t *testing.T) {
+// clipmenud is a bash script: its process is named "bash" and only its command line names clipmenud
+// (issue 860: collecting was false while the daemon ran).
+func TestCollectingSeesClipmenudRunAsABashScript(t *testing.T) {
 	store(t, map[string]string{"first": "first"}, "first")
-	fakeProcess(t, nobody, "clipmenud") // owned by the test's uid: the operator's
-	u, err := user.Current()
-	if err != nil {
-		t.Skip(err)
+	fakeProcess(t, nobody, "bash")
+	cmdline := filepath.Join(procRoot, strconv.Itoa(nobody), "cmdline")
+	if err := os.WriteFile(cmdline, []byte("bash\x00/usr/bin/clipmenud\x00"), 0o644); err != nil {
+		t.Fatal(err)
 	}
-	t.Setenv("MESH_OPERATOR_ACCOUNT", u.Username)
-	old := toolUID
-	toolUID = func() int { return os.Getuid() + 1 }
-	t.Cleanup(func() { toolUID = old })
-	h, err := History(10)
-	if err != nil || !h.Collecting {
-		t.Fatalf("the operator's clipmenud runs: %+v %v", h, err)
+	if h, err := History(10); err != nil || !h.Collecting {
+		t.Fatalf("clipmenud runs as a bash script: %+v %v", h, err)
 	}
-	// without the operator named, the tool's own uid stands, and that account has no daemon
-	t.Setenv("MESH_OPERATOR_ACCOUNT", "")
+	// another bash script is not the daemon
+	os.WriteFile(cmdline, []byte("bash\x00/usr/bin/other\x00"), 0o644)
 	if h, _ := History(10); h.Collecting {
-		t.Fatalf("another account's daemon counted: %+v", h)
+		t.Fatalf("a bash script that is not clipmenud counted: %+v", h)
 	}
 }

modules/clipmenu/cmd/clipmenu-tools/session.go

@@ -21,7 +21,6 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
-	"os/user"
 	"path/filepath"
 	"sort"
 	"strconv"
@@ -387,31 +386,13 @@ func (c *capped) Write(p []byte) (int, error) {
 	return c.Buffer.Write(p)
 }
 
-// toolUID is the uid the tool runs as; a test replaces it to stand for a tool that runs as another
-// account than the operator's.
-var toolUID = os.Getuid
-
-// operatorUID is the uid of the operator's account, whose clipmenud and store these tools look at.
-// The runtime serves the tools as an account that need not be the operator's and names the operator
-// in MESH_OPERATOR_ACCOUNT; without it (or when it is unknown here) the tool's own uid stands.
-func operatorUID() int {
-	if name := strings.TrimSpace(os.Getenv("MESH_OPERATOR_ACCOUNT")); name != "" {
-		if u, err := user.Lookup(name); err == nil {
-			if id, err := strconv.Atoi(u.Uid); err == nil {
-				return id
-			}
-		}
-	}
-	return toolUID()
-}
-
-// processesOf are the pids of the operator account's processes whose command name is comm, oldest first.
+// processesOf are the pids of this uid's processes whose command name is comm, oldest first.
 func processesOf(comm string) []int {
 	entries, err := os.ReadDir(procRoot)
 	if err != nil {
 		return nil
 	}
-	uid := operatorUID()
+	uid := os.Getuid()
 	var pids []int
 	for _, e := range entries {
 		pid, err := strconv.Atoi(e.Name())
@@ -422,7 +403,7 @@ func processesOf(comm string) []int {
 		if owner, ok := ownerOf(dir); !ok || owner != uid {
 			continue
 		}
-		if readTrimmed(filepath.Join(dir, "comm")) == comm {
+		if readTrimmed(filepath.Join(dir, "comm")) == comm || runsScript(dir, comm) {
 			pids = append(pids, pid)
 		}
 	}
@@ -430,7 +411,25 @@ func processesOf(comm string) []int {
 	return pids
 }
 
-// signalAll sends sig to every process of the operator account named comm, and answers the pids it reached.
+// runsScript is whether the process is an interpreter running the script named name: clipmenud is a
+// bash script, so its comm is "bash" and only its command line, "bash /usr/bin/clipmenud", names it.
+func runsScript(procDir, name string) bool {
+	raw, err := os.ReadFile(filepath.Join(procDir, "cmdline"))
+	if err != nil {
+		return false
+	}
+	args := strings.Split(strings.TrimRight(string(raw), "\x00"), "\x00")
+	if len(args) < 2 {
+		return false
+	}
+	switch filepath.Base(args[0]) {
+	case "bash", "sh", "dash", "zsh", "env":
+		return filepath.Base(args[1]) == name
+	}
+	return false
+}
+
+// signalAll sends sig to every process of this uid named comm, and answers the pids it reached.
 func signalAll(comm string, sig syscall.Signal) []int {
 	var reached []int
 	for _, pid := range processesOf(comm) {