Merge pull request #757 from Lomanic/darwin-process-exe-cgo-implementation

[darwin][process] Add cgo implementation of Exe() from PR #243

process/process_darwin.go

@@ -99,28 +99,6 @@ func (p *Process) Exe() (string, error) {
 	return p.ExeWithContext(context.Background())
 }
 
-func (p *Process) ExeWithContext(ctx context.Context) (string, error) {
-	lsof_bin, err := exec.LookPath("lsof")
-	if err != nil {
-		return "", err
-	}
-	out, err := invoke.CommandWithContext(ctx, lsof_bin, "-p", strconv.Itoa(int(p.Pid)), "-Fpfn")
-	if err != nil {
-		return "", fmt.Errorf("bad call to lsof: %s", err)
-	}
-	txtFound := 0
-	lines := strings.Split(string(out), "\n")
-	for i := 1; i < len(lines); i += 2 {
-		if lines[i] == "ftxt" {
-			txtFound++
-			if txtFound == 2 {
-				return lines[i-1][1:], nil
-			}
-		}
-	}
-	return "", fmt.Errorf("missing txt data returned by lsof")
-}
-
 // Cmdline returns the command line arguments of the process as a string with
 // each argument separated by 0x20 ascii character.
 func (p *Process) Cmdline() (string, error) {

process/process_darwin_cgo.go

@@ -0,0 +1,30 @@
+// +build darwin
+// +build cgo
+
+package process
+
+// #include <stdlib.h>
+// #include <libproc.h>
+import "C"
+import (
+	"context"
+	"fmt"
+	"unsafe"
+)
+
+func (p *Process) ExeWithContext(ctx context.Context) (string, error) {
+	var c C.char // need a var for unsafe.Sizeof need a var
+	const bufsize = C.PROC_PIDPATHINFO_MAXSIZE * unsafe.Sizeof(c)
+	buffer := (*C.char)(C.malloc(C.size_t(bufsize)))
+	defer C.free(unsafe.Pointer(buffer))
+
+	ret, err := C.proc_pidpath(C.int(p.Pid), unsafe.Pointer(buffer), C.uint32_t(bufsize))
+	if err != nil {
+		return "", err
+	}
+	if ret <= 0 {
+		return "", fmt.Errorf("unknown error: proc_pidpath returned %d", ret)
+	}
+
+	return C.GoString(buffer), nil
+}

process/process_darwin_nocgo.go

@@ -0,0 +1,34 @@
+// +build darwin
+// +build !cgo
+
+package process
+
+import (
+	"context"
+	"fmt"
+	"os/exec"
+	"strconv"
+	"strings"
+)
+
+func (p *Process) ExeWithContext(ctx context.Context) (string, error) {
+	lsof_bin, err := exec.LookPath("lsof")
+	if err != nil {
+		return "", err
+	}
+	out, err := invoke.CommandWithContext(ctx, lsof_bin, "-p", strconv.Itoa(int(p.Pid)), "-Fpfn")
+	if err != nil {
+		return "", fmt.Errorf("bad call to lsof: %s", err)
+	}
+	txtFound := 0
+	lines := strings.Split(string(out), "\n")
+	for i := 1; i < len(lines); i += 2 {
+		if lines[i] == "ftxt" {
+			txtFound++
+			if txtFound == 2 {
+				return lines[i-1][1:], nil
+			}
+		}
+	}
+	return "", fmt.Errorf("missing txt data returned by lsof")
+}