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Diffstat (limited to 'node_modules/write-file-atomic/index.js')
| -rw-r--r-- | node_modules/write-file-atomic/index.js | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/node_modules/write-file-atomic/index.js b/node_modules/write-file-atomic/index.js new file mode 100644 index 00000000..3b5607d1 --- /dev/null +++ b/node_modules/write-file-atomic/index.js @@ -0,0 +1,199 @@ +'use strict' +module.exports = writeFile +module.exports.sync = writeFileSync +module.exports._getTmpname = getTmpname // for testing +module.exports._cleanupOnExit = cleanupOnExit + +var fs = require('graceful-fs') +var MurmurHash3 = require('imurmurhash') +var onExit = require('signal-exit') +var path = require('path') +var activeFiles = {} + +var invocations = 0 +function getTmpname (filename) { + return filename + '.' + + MurmurHash3(__filename) + .hash(String(process.pid)) + .hash(String(++invocations)) + .result() +} + +function cleanupOnExit (tmpfile) { + return function () { + try { + fs.unlinkSync(typeof tmpfile === 'function' ? tmpfile() : tmpfile) + } catch (_) {} + } +} + +function writeFile (filename, data, options, callback) { + if (options instanceof Function) { + callback = options + options = null + } + if (!options) options = {} + + var Promise = options.Promise || global.Promise + var truename + var fd + var tmpfile + var removeOnExit = cleanupOnExit(() => tmpfile) + var absoluteName = path.resolve(filename) + + new Promise(function serializeSameFile (resolve) { + // make a queue if it doesn't already exist + if (!activeFiles[absoluteName]) activeFiles[absoluteName] = [] + + activeFiles[absoluteName].push(resolve) // add this job to the queue + if (activeFiles[absoluteName].length === 1) resolve() // kick off the first one + }).then(function getRealPath () { + return new Promise(function (resolve) { + fs.realpath(filename, function (_, realname) { + truename = realname || filename + tmpfile = getTmpname(truename) + resolve() + }) + }) + }).then(function stat () { + return new Promise(function stat (resolve) { + if (options.mode && options.chown) resolve() + else { + // Either mode or chown is not explicitly set + // Default behavior is to copy it from original file + fs.stat(truename, function (err, stats) { + if (err || !stats) resolve() + else { + options = Object.assign({}, options) + + if (!options.mode) { + options.mode = stats.mode + } + if (!options.chown && process.getuid) { + options.chown = { uid: stats.uid, gid: stats.gid } + } + resolve() + } + }) + } + }) + }).then(function thenWriteFile () { + return new Promise(function (resolve, reject) { + fs.open(tmpfile, 'w', options.mode, function (err, _fd) { + fd = _fd + if (err) reject(err) + else resolve() + }) + }) + }).then(function write () { + return new Promise(function (resolve, reject) { + if (Buffer.isBuffer(data)) { + fs.write(fd, data, 0, data.length, 0, function (err) { + if (err) reject(err) + else resolve() + }) + } else if (data != null) { + fs.write(fd, String(data), 0, String(options.encoding || 'utf8'), function (err) { + if (err) reject(err) + else resolve() + }) + } else resolve() + }) + }).then(function syncAndClose () { + if (options.fsync !== false) { + return new Promise(function (resolve, reject) { + fs.fsync(fd, function (err) { + if (err) reject(err) + else fs.close(fd, resolve) + }) + }) + } + }).then(function chown () { + if (options.chown) { + return new Promise(function (resolve, reject) { + fs.chown(tmpfile, options.chown.uid, options.chown.gid, function (err) { + if (err) reject(err) + else resolve() + }) + }) + } + }).then(function chmod () { + if (options.mode) { + return new Promise(function (resolve, reject) { + fs.chmod(tmpfile, options.mode, function (err) { + if (err) reject(err) + else resolve() + }) + }) + } + }).then(function rename () { + return new Promise(function (resolve, reject) { + fs.rename(tmpfile, truename, function (err) { + if (err) reject(err) + else resolve() + }) + }) + }).then(function success () { + removeOnExit() + callback() + }).catch(function fail (err) { + removeOnExit() + fs.unlink(tmpfile, function () { + callback(err) + }) + }).then(function checkQueue () { + activeFiles[absoluteName].shift() // remove the element added by serializeSameFile + if (activeFiles[absoluteName].length > 0) { + activeFiles[absoluteName][0]() // start next job if one is pending + } else delete activeFiles[absoluteName] + }) +} + +function writeFileSync (filename, data, options) { + if (!options) options = {} + try { + filename = fs.realpathSync(filename) + } catch (ex) { + // it's ok, it'll happen on a not yet existing file + } + var tmpfile = getTmpname(filename) + + try { + if (!options.mode || !options.chown) { + // Either mode or chown is not explicitly set + // Default behavior is to copy it from original file + try { + var stats = fs.statSync(filename) + options = Object.assign({}, options) + if (!options.mode) { + options.mode = stats.mode + } + if (!options.chown && process.getuid) { + options.chown = { uid: stats.uid, gid: stats.gid } + } + } catch (ex) { + // ignore stat errors + } + } + + var removeOnExit = onExit(cleanupOnExit(tmpfile)) + var fd = fs.openSync(tmpfile, 'w', options.mode) + if (Buffer.isBuffer(data)) { + fs.writeSync(fd, data, 0, data.length, 0) + } else if (data != null) { + fs.writeSync(fd, String(data), 0, String(options.encoding || 'utf8')) + } + if (options.fsync !== false) { + fs.fsyncSync(fd) + } + fs.closeSync(fd) + if (options.chown) fs.chownSync(tmpfile, options.chown.uid, options.chown.gid) + if (options.mode) fs.chmodSync(tmpfile, options.mode) + fs.renameSync(tmpfile, filename) + removeOnExit() + } catch (err) { + removeOnExit() + try { fs.unlinkSync(tmpfile) } catch (e) {} + throw err + } +} |