1 files changed, 46 insertions, 0 deletions
diff --git a/node_modules/dir-compare/src/fs/BufferPool.js b/node_modules/dir-compare/src/fs/BufferPool.js
new file mode 100644
index 0000000..48febce
--- /dev/null
+++ b/node_modules/dir-compare/src/fs/BufferPool.js
@@ -0,0 +1,46 @@
+/**
+ * Collection of buffers to be shared between async processes.
+ * Avoids allocating buffers each time async process starts.
+ * bufSize - size of each buffer
+ * bufNo - number of buffers
+ * Caller has to make sure no more than bufNo async processes run simultaneously.
+ */
+function BufferPool(bufSize, bufNo) {
+    var bufferPool = []
+    for (var i = 0; i < bufNo; i++) {
+        bufferPool.push({
+            buf1: alloc(bufSize),
+            buf2: alloc(bufSize),
+            busy: false
+        })
+    }
+
+    var allocateBuffers = function () {
+        for (var j = 0; j < bufNo; j++) {
+            var bufferPair = bufferPool[j]
+            if (!bufferPair.busy) {
+                bufferPair.busy = true
+                return bufferPair
+            }
+        }
+        throw new Error('Async buffer limit reached')
+    }
+
+    return {
+        allocateBuffers: allocateBuffers,
+        freeBuffers: freeBuffers
+    }
+
+    function freeBuffers(bufferPair) {
+        bufferPair.busy = false
+    }
+}
+
+function alloc(bufSize) {
+    if (Buffer.alloc) {
+        return Buffer.alloc(bufSize)
+    }
+    return new Buffer(bufSize)
+}
+
+module.exports = BufferPool