chushihua

2026-01-26 23:20:48 +08:00
commit 7b5aab0206
22521 changed files with 3300090 additions and 0 deletions
@@ -0,0 +1,125 @@
+'use strict'
+
+const BB = require('bluebird')
+
+const contentPath = require('./path')
+const fs = require('graceful-fs')
+const PassThrough = require('stream').PassThrough
+const pipe = BB.promisify(require('mississippi').pipe)
+const ssri = require('ssri')
+const Y = require('../util/y.js')
+
+BB.promisifyAll(fs)
+
+module.exports = read
+function read (cache, integrity, opts) {
+  opts = opts || {}
+  return pickContentSri(cache, integrity).then(content => {
+    const sri = content.sri
+    const cpath = contentPath(cache, sri)
+    return fs.readFileAsync(cpath, null).then(data => {
+      if (typeof opts.size === 'number' && opts.size !== data.length) {
+        throw sizeError(opts.size, data.length)
+      } else if (ssri.checkData(data, sri)) {
+        return data
+      } else {
+        throw integrityError(sri, cpath)
+      }
+    })
+  })
+}
+
+module.exports.stream = readStream
+module.exports.readStream = readStream
+function readStream (cache, integrity, opts) {
+  opts = opts || {}
+  const stream = new PassThrough()
+  pickContentSri(
+    cache, integrity
+  ).then(content => {
+    const sri = content.sri
+    return pipe(
+      fs.createReadStream(contentPath(cache, sri)),
+      ssri.integrityStream({
+        integrity: sri,
+        size: opts.size
+      }),
+      stream
+    )
+  }).catch(err => {
+    stream.emit('error', err)
+  })
+  return stream
+}
+
+if (fs.copyFile) {
+  module.exports.copy = copy
+}
+function copy (cache, integrity, dest, opts) {
+  opts = opts || {}
+  return pickContentSri(cache, integrity).then(content => {
+    const sri = content.sri
+    const cpath = contentPath(cache, sri)
+    return fs.copyFileAsync(cpath, dest).then(() => content.size)
+  })
+}
+
+module.exports.hasContent = hasContent
+function hasContent (cache, integrity) {
+  if (!integrity) { return BB.resolve(false) }
+  return pickContentSri(cache, integrity)
+  .catch({code: 'ENOENT'}, () => false)
+  .catch({code: 'EPERM'}, err => {
+    if (process.platform !== 'win32') {
+      throw err
+    } else {
+      return false
+    }
+  }).then(content => {
+    if (!content.sri) return false
+    return ({ sri: content.sri, size: content.stat.size })
+  })
+}
+
+module.exports._pickContentSri = pickContentSri
+function pickContentSri (cache, integrity) {
+  const sri = ssri.parse(integrity)
+  // If `integrity` has multiple entries, pick the first digest
+  // with available local data.
+  const algo = sri.pickAlgorithm()
+  const digests = sri[algo]
+  if (digests.length <= 1) {
+    const cpath = contentPath(cache, digests[0])
+    return fs.lstatAsync(cpath).then(stat => ({ sri: digests[0], stat }))
+  } else {
+    return BB.any(sri[sri.pickAlgorithm()].map(meta => {
+      return pickContentSri(cache, meta)
+    }))
+    .catch(err => {
+      if ([].some.call(err, e => e.code === 'ENOENT')) {
+        throw Object.assign(
+          new Error('No matching content found for ' + sri.toString()),
+          {code: 'ENOENT'}
+        )
+      } else {
+        throw err[0]
+      }
+    })
+  }
+}
+
+function sizeError (expected, found) {
+  var err = new Error(Y`Bad data size: expected inserted data to be ${expected} bytes, but got ${found} instead`)
+  err.expected = expected
+  err.found = found
+  err.code = 'EBADSIZE'
+  return err
+}
+
+function integrityError (sri, path) {
+  var err = new Error(Y`Integrity verification failed for ${sri} (${path})`)
+  err.code = 'EINTEGRITY'
+  err.sri = sri
+  err.path = path
+  return err
+}