tools: run tick processor without forking

Using the tick processor no longer creates temporary files or spawns a
child process.

PR-URL: https://github.com/nodejs/node/pull/4224
Reviewed-By: bnoordhuis - Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: jasnell - James M Snell <jasnell@gmail.com>

1 files changed, 15 insertions, 13 deletions

diff --git a/lib/internal/v8_prof_polyfill.js b/lib/internal/v8_prof_polyfill.js
index 1beae0e4e4b..755f8f0d65d 100644
--- a/lib/internal/v8_prof_polyfill.js
+++ b/lib/internal/v8_prof_polyfill.js
@@ -26,40 +26,42 @@
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 // Node polyfill
-var fs = require('fs');
-var os = {
+const fs = require('fs');
+const cp = require('child_process');
+const os = {
   system: function(name, args) {
     if (process.platform === 'linux' && name === 'nm') {
       // Filter out vdso and vsyscall entries.
-      var arg = args[args.length - 1];
+      const arg = args[args.length - 1];
       if (arg === '[vdso]' ||
           arg == '[vsyscall]' ||
           /^[0-9a-f]+-[0-9a-f]+$/.test(arg)) {
         return '';
       }
+    } else if (process.platform === 'darwin') {
+      args.unshift('-c', name);
+      name = '/bin/sh';
     }
-    return require('child_process').execFileSync(
-        name, args, {encoding: 'utf8'});
+    return cp.spawnSync(name, args).stdout.toString();
   }
 };
-var print = console.log;
+const print = console.log;
 function read(fileName) {
   return fs.readFileSync(fileName, 'utf8');
 }
-arguments = process.argv.slice(2);
-var quit = process.exit;
+const quit = process.exit;
 
 // Polyfill "readline()".
-var logFile = arguments[arguments.length - 1];
+const logFile = arguments[arguments.length - 1];
 try {
   fs.accessSync(logFile);
 } catch(e) {
   console.error('Please provide a valid isolate file as the final argument.');
   process.exit(1);
 }
-var fd = fs.openSync(logFile, 'r');
-var buf = new Buffer(4096);
-var dec = new (require('string_decoder').StringDecoder)('utf-8');
+const fd = fs.openSync(logFile, 'r');
+const buf = new Buffer(4096);
+const dec = new (require('string_decoder').StringDecoder)('utf-8');
 var line = '';
 versionCheck();
 function readline() {
@@ -85,7 +87,7 @@ function versionCheck() {
   var firstLine = readline();
   line = firstLine + '\n' + line;
   firstLine = firstLine.split(',');
-  var curVer = process.versions.v8.split('.');
+  const curVer = process.versions.v8.split('.');
   if (firstLine.length !== 6 && firstLine[0] !== 'v8-version') {
     console.log('Unable to read v8-version from log file.');
     return;