modify file code

wangding · wangding · commit 359b7533e0e3 · 2023-10-15T20:25:47.000+08:00
diff --git a/10-file-system/01-my-cat-async.js b/10-file-system/01-my-cat-async.js
@@ -1,7 +1,7 @@
 #!/usr/bin/env node
 
 const fs   = require('fs'),
-      file = process.argv[2] || __filename;
+      file = process.argv[2] ?? __filename;
 
 fs.readFile(file, (err, buf) => {
   if(err) {
diff --git a/10-file-system/02-my-cat-lower.js b/10-file-system/02-my-cat-lower.js
@@ -1,7 +1,7 @@
 #!/usr/bin/env node
 
 const fs   = require('fs'),
-      file = process.argv[2] || __filename;
+      file = process.argv[2] ?? __filename;
 
 try {
   let len = fs.statSync(file).size,
@@ -10,6 +10,7 @@ try {
 
   fs.readSync(fid, buf, 0, len, 0);
   console.log(buf.toString('utf8'));
+  fs.closeSync(fid);
 } catch(e) {
   console.error(e.message);
   process.exit(1);
diff --git a/10-file-system/02-my-cat-promise.js b/10-file-system/02-my-cat-promise.js
@@ -1,13 +1,12 @@
 #!/usr/bin/env node
 
-import { readFile } from 'fs/promises';
+const { readFile } = require('fs/promises');
 
-const file = process.argv[2];
+const file = process.argv[2] ?? __filename;
 
 async function main() {
   try {
-    const content = await readFile(file, 'utf8');
-    console.log(content);
+    console.log(await readFile(file, 'utf8'));
   } catch(e) {
     console.error(e.message);
   }
diff --git a/10-file-system/03-my-cat-mix.js b/10-file-system/03-my-cat-mix.js
@@ -1,11 +1,12 @@
 #!/usr/bin/env node
 
 const fs   = require('fs'),
-      file = process.argv[2] || __filename;
+      file = process.argv[2] ?? __filename;
 
 try {
   const fid = fs.openSync(file, 'r');
-  fs.writeSync(1, fs.readFileSync(fid).toString('utf8'));
+  //console.log(fs.readFileSync(fid, 'utf8'));
+  fs.writeSync(1, fs.readFileSync(fid, 'utf8'));
   fs.closeSync(fid);
 } catch (e) {
   console.error(e.message);
diff --git a/10-file-system/04-my-cat-stream.js b/10-file-system/04-my-cat-stream.js
@@ -2,16 +2,19 @@
 
 const fs   = require('fs'),
       err  = console.error,
-      file = process.argv[2] || __filename;
+      file = process.argv[2] ?? __filename;
 
 if(!fs.existsSync(file)) {
   err('%s not exist!', file);
   process.exit(1);
 }
-  
+
 if(!fs.statSync(file).isFile()) {
   err('%s is not file!', file);
   process.exit(2);
 }
 
-fs.createReadStream(file).pipe(process.stdout);
+//fs.createReadStream(file).pipe(process.stdout);
+
+const src = fs.createReadStream(file, 'utf8');
+src.on('data', console.log);
diff --git a/10-file-system/05-my-cat-sync.js b/10-file-system/05-my-cat-sync.js
@@ -1,10 +1,10 @@
 #!/usr/bin/env node
 
 const fs   = require('fs'),
-      file = process.argv[2] || __filename;
+      file = process.argv[2] ?? __filename;
 
 try{
-  console.log(fs.readFileSync(file).toString('utf8'));
+  console.log(fs.readFileSync(file, 'utf8'));
 } catch(err) {
   console.error(err.message);
   process.exit(1);
diff --git a/10-file-system/06-my-cp.js b/10-file-system/06-my-cp.js
@@ -9,7 +9,7 @@ if(!fs.existsSync(src)) {
   err('%s not exist!', src);
   process.exit(1);
 }
-  
+
 if(!fs.statSync(src).isFile()) {
   err('%s is not file!', src);
   process.exit(2);
diff --git a/10-file-system/10-my-ls.js b/10-file-system/10-my-ls.js
@@ -1,7 +1,7 @@
 #!/usr/bin/env node
 
 const fs  = require('fs'),
-      dir = process.argv[2] || __dirname;
+      dir = process.argv[2] ?? __dirname;
 
 try {
   console.log(fs.readdirSync(dir));
diff --git a/10-file-system/12-my-rm-dir.js b/10-file-system/12-my-rm-dir.js
@@ -1,12 +1,11 @@
 #!/usr/bin/env node
 
 const fs  = require('fs'),
-      err = console.error,
       dir = process.argv[2];
 
 try {
   fs.rmdirSync(dir);
 } catch(e) {
-  err(e.message);
+  console.error(e.message);
   process.exit(1);
 }
diff --git a/10-file-system/13-my-ln.js b/10-file-system/13-my-ln.js
@@ -4,7 +4,7 @@ const fs  = require('fs'),
       err = console.error;
 
 let opt = {
-  '4': createhardLink,
+  '4': createHardLink,
   '5': createSoftLink
 };
 
@@ -25,7 +25,7 @@ function createSoftLink() {
   }
 }
 
-function createhardLink() {
+function createHardLink() {
   let src = process.argv[2],
       lnk = process.argv[3];
 
diff --git a/10-file-system/16-my-chown.js b/10-file-system/16-my-chown.js
@@ -2,8 +2,8 @@
 
 const fs   = require('fs'),
       err  = console.error,
-      uid  = process.argv[2],
-      gid  = process.argv[3],
+      uid  = Number(process.argv[2]),
+      gid  = Number(process.argv[3]),
       file = process.argv[4];
 
 if(process.argv.length !== 5) {
@@ -12,7 +12,7 @@ if(process.argv.length !== 5) {
 }
 
 try{
-  fs.chownSync(file, Number(uid), Number(gid));
+  fs.chownSync(file, uid, gid);
 } catch(e) {
   err(e.message);
   process.exit(2);
diff --git a/10-file-system/17-my-stat.js b/10-file-system/17-my-stat.js
@@ -1,7 +1,7 @@
 #!/usr/bin/env node
 
 const fs  = require('fs'),
-      src = process.argv[2] || __filename;
+      src = process.argv[2] ?? __filename;
 
 try{
   console.log(fs.statSync(src));
diff --git a/10-file-system/18-watch.js b/10-file-system/18-watch.js
@@ -1,17 +1,26 @@
 #!/usr/bin/env node
 
 const fs  = require('fs'),
-      log = console.log;
+      log = console.log,
+      dir = process.argv[2] ?? __dirname;
 
-let w = fs.watch(__dirname, log);
+if(!fs.existsSync(dir)) {
+  console.error('%s not exists.', dir);
+  process.exit(1);
+}
+
+if(!fs.statSync(dir).isDirectory()) {
+  console.error('%s is not directory.', dir);
+  process.exit(1);
+}
+
+const w = fs.watch(dir, log);
 
 process.on('SIGINT', () => {
   w.close();
 
   log('unwitch the directory');
   log('Game over after 5 second...');
 
-  setTimeout(() => {
-    process.exit();
-  }, 5000);
+  setTimeout(process.exit, 5000);
 });
diff --git a/10-file-system/19-my-rm.js b/10-file-system/19-my-rm.js
@@ -10,27 +10,20 @@ if(typeof(src) === 'undefined') {
 }
 
 if(!fs.existsSync(src)) {
-  console.error('%s not exist!', src);
+  console.error('%s not exists!', src);
   process.exit(2);
 }
 
-if(fs.statSync(src).isFile())  fs.unlinkSync(src);
-
-if(fs.statSync(src).isDirectory()) deleteDir(src);
-
 function deleteDir(folder) {
   let files = fs.readdirSync(folder);
 
   for(let i=0; i<files.length; i++) {
-    let file = join(folder, files[i]);
-
-    if(fs.statSync(file).isFile()) {
-      fs.unlinkSync(file);
-      continue;
-    }
-
-    if(fs.statSync(file).isDirectory()) deleteDir(file);
+    const file = join(folder, files[i]);
+    fs.statSync(file).isDirectory() ? deleteDir(file) : fs.unlinkSync(file);
   }
 
   fs.rmdirSync(folder);
 }
+
+if(fs.statSync(src).isFile())      fs.unlinkSync(src);
+if(fs.statSync(src).isDirectory()) deleteDir(src);
diff --git a/10-file-system/20-ls-inode.js b/10-file-system/20-ls-inode.js
@@ -1,19 +1,26 @@
 #!/usr/bin/env node
 
+/* 递归打印目录下的子目录或文件的硬链接数和 inode 值 */
+
 const fs   = require('fs'),
-      join = require('path').join,
       log  = console.log,
-      src  = process.argv[2] || 'root';
+      join = require('path').join,
+      src  = process.argv[2] ?? 'root';
 
-let res = validate();
+function main() {
+  const res = validate();
+
+  if(res.code !== 0) {
+    console.error(res.msg);
+    process.exit(res.code);
+  }
 
-if(res.code !== 0) {
-  console.error(res.msg);
-  process.exit(res.code);
+  logInode(src);
+  log('---');
+  lsInode(src);
 }
 
-logInode(src);
-lsInode(src);
+main();
 
 function lsInode(folder) {
   let files = fs.readdirSync(folder);
@@ -37,7 +44,8 @@ function lsInode(folder) {
 
 function logInode(folder) {
   let last = folder.split('/').pop();
-  let dir = '', space = '                                   ';
+  let dir  = '',
+      space = ' '.repeat(20);
 
   if(last === '.') {
     folder = folder.slice(0, folder.length-1);
diff --git a/10-file-system/21-bin.js b/10-file-system/21-bin.js
@@ -1,8 +1,7 @@
 #!/usr/bin/env node
 
-const fs = require('fs'),
+const fs  = require('fs'),
       buf = Buffer.alloc(256);
 
 for(let i=0; i<buf.length; i++) buf[i] = i;
-
 fs.writeFileSync('test.bin', buf, 'binary');
diff --git a/10-file-system/22-readline.js b/10-file-system/22-readline.js
@@ -0,0 +1,11 @@
+#!/usr/bin/env node
+
+const readline = require('readline'),
+      fs       = require('fs'),
+      fileName = process.argv[2] ?? __filename,
+      input    = fs.createReadStream(fileName),
+      rl       = readline.createInterface({ input, crlfDelay: Infinity });
+
+let num = 1;
+rl.on('line', line => console.log(`${num++}\t${line}`));
+rl.on('end', process.exit);
diff --git a/10-file-system/23-cpu-info.js b/10-file-system/23-cpu-info.js
@@ -0,0 +1,7 @@
+#!/usr/bin/env node
+
+const fs = require('fs');
+
+process.platform == 'linux' ?
+  console.log(fs.readFileSync('/proc/cpuinfo', 'utf8')) :
+  console.error('当前的操作系统不支持');
diff --git a/10-file-system/24-ps.js b/10-file-system/24-ps.js
@@ -0,0 +1,67 @@
+#!/usr/bin/env node
+
+const fs     = require('fs'),
+      {join} = require('path');
+
+function isProcessDir(dir) {
+  return Number.isInteger(Number(dir)) && 
+    fs.statSync(join('/proc', dir)).isDirectory();
+}
+
+function getProcessInfo(pid) {
+  return {
+    PID: pid,
+    VSZ: getVmSize(pid),
+    RSS: getVmRSS(pid),
+    CMD: getCmdline(pid),
+  };
+}
+
+function getCmdline(pid) {
+  let cmdline = fs.readFileSync(`/proc/${pid}/cmdline`, 'utf8');
+  return cmdline.replace(/\x00/g, ' ').trimEnd();
+}
+
+function getVmSize(pid) {
+  const data = fs.readFileSync(`/proc/${pid}/status`, 'utf8');
+  try {
+    return data.match(/VmSize:\s*(\d+)/)[1];
+  } catch {
+    return 0;
+  }
+}
+
+function getVmRSS(pid) {
+  const data = fs.readFileSync(`/proc/${pid}/status`, 'utf8');
+  try {
+    return data.match(/VmRSS:\s*(\d+)/)[1];
+  } catch {
+    return 0;
+  }
+}
+
+function main() {
+  let dirs = fs.readdirSync('/proc');
+  dirs = dirs.filter(isProcessDir);
+  dirs.forEach(dir => console.log(getProcessInfo(dir)));
+}
+
+main();
+
+/*
+"ps aux"命令的各个字段可以在"/proc/pid"目录下的不同文件中找到以下信息：
+%MEM：可以从"/proc/pid/statm"文件中的第 2 个字段（resident set size）计算得出。
+告诉我 %MEM 是怎么计算出来的
+
+
+ok-8. STAT：可以从"/proc/pid/stat"文件中的第 3 个字段（state）获取。
+
+3. %CPU：可以从"/proc/pid/stat"文件中的第 14 个字段（utime）和第 15 个字段（stime）计算
+得出。
+7. TTY：可以从"/proc/pid/stat"文件中的第 7 个字段（tty_nr）获取，并与"/dev"目录下的终端
+设备进行匹配。
+9. START：可以从"/proc/pid/stat"文件中的第 22 个字段（start_time）获取，并经过转换为可读时间格式。
+10. TIME：可以从"/proc/pid/stat"文件中的第 14 个字段（utime）和第 15 个字段（stime）计算得出。
+
+4. %MEM：可以从"/proc/pid/statm"文件中的第 2 个字段（resident set size）计算得出。
+*/
diff --git a/10-file-system/25-read-cfg.js b/10-file-system/25-read-cfg.js
@@ -0,0 +1,11 @@
+#!/usr/bin/env node
+
+const fs  = require('fs'),
+      log = console.log;
+
+let cfg = fs.readFileSync('../package.json', 'utf8');
+cfg = JSON.parse(cfg);
+
+log(`name: ${cfg.name}`);
+log(`version: ${cfg.version}`);
+log(`description: ${cfg.description}`);
diff --git a/10-file-system/26-web-log.js b/10-file-system/26-web-log.js
diff --git a/10-file-system/27-passwd-fp.js b/10-file-system/27-passwd-fp.js
diff --git a/10-file-system/27-passwd.js b/10-file-system/27-passwd.js

Original file line number	Diff line number	Diff line change
`@@ -9,7 +9,7 @@ if(!fs.existsSync(src)) {`
`9`	`9`	`err('%s not exist!', src);`
`10`	`10`	`process.exit(1);`
`11`	`11`	`}`
`12`		`-`
	`12`	`+`
`13`	`13`	`if(!fs.statSync(src).isFile()) {`
`14`	`14`	`err('%s is not file!', src);`
`15`	`15`	`process.exit(2);`
Original file line number	Diff line number	Diff line change
`@@ -4,7 +4,7 @@ const fs = require('fs'),`
`4`	`4`	`err = console.error;`
`5`	`5`
`6`	`6`	`let opt = {`
`7`		`- '4': createhardLink,`
	`7`	`+ '4': createHardLink,`
`8`	`8`	`'5': createSoftLink`
`9`	`9`	`};`
`10`	`10`
`@@ -25,7 +25,7 @@ function createSoftLink() {`
`25`	`25`	`}`
`26`	`26`	`}`
`27`	`27`
`28`		`-function createhardLink() {`
	`28`	`+function createHardLink() {`
`29`	`29`	`let src = process.argv[2],`
`30`	`30`	`lnk = process.argv[3];`
`31`	`31`