moved streams code around, added stub for DateRollingFileStream

lib/streams/BaseRollingFileStream.js

@@ -0,0 +1,91 @@
+var fs = require('fs'),
+    util = require('util');
+
+function debug(message) {
+//    util.debug(message);
+//    console.log(message);
+}
+
+module.exports = BaseRollingFileStream;
+
+function BaseRollingFileStream(filename, options) {
+    this.filename = filename;
+    this.options = options || { encoding: 'utf8', mode: 0644, flags: 'a' };
+    this.rolling = false;
+    this.writesWhileRolling = [];
+    this.currentSize = 0;
+
+    function currentFileSize(file) {
+        var fileSize = 0;
+        try {
+            fileSize = fs.statSync(file).size;
+        } catch (e) {
+            // file does not exist
+        }
+        return fileSize;
+    }
+
+    function throwErrorIfArgumentsAreNotValid() {
+        if (!filename) {
+            throw new Error("You must specify a filename");
+        }
+    }
+
+    throwErrorIfArgumentsAreNotValid();
+
+    BaseRollingFileStream.super_.call(this, this.filename, this.options);
+    this.currentSize = currentFileSize(this.filename);
+}
+util.inherits(BaseRollingFileStream, fs.FileWriteStream);
+
+BaseRollingFileStream.prototype.initRolling = function() {
+    var that = this;
+
+    function emptyRollingQueue() {
+        debug("emptying the rolling queue");
+        var toWrite;
+        while ((toWrite = that.writesWhileRolling.shift())) {
+            BaseRollingFileStream.super_.prototype.write.call(that, toWrite.data, toWrite.encoding);
+            that.currentSize += toWrite.data.length;
+            if (that.shouldRoll()) {
+                that.flush();
+                return true;
+            }
+        }
+        that.flush();
+        return false;
+    }
+
+    this.rolling = true;
+    this.roll(this.filename, function() {
+        that.currentSize = 0;
+        that.rolling = emptyRollingQueue();
+        if (that.rolling) {
+            process.nextTick(function() { that.initRolling(); });
+        }
+    });
+};
+
+BaseRollingFileStream.prototype.write = function(data, encoding) {
+    if (this.rolling) {
+        this.writesWhileRolling.push({ data: data, encoding: encoding });
+        return false;
+    } else {
+        var canWrite = BaseRollingFileStream.super_.prototype.write.call(this, data, encoding);
+        this.currentSize += data.length;
+        debug('current size = ' + this.currentSize);
+        if (this.shouldRoll()) {
+            this.initRolling();
+        }
+        return canWrite;
+    }
+};
+
+BaseRollingFileStream.prototype.shouldRoll = function() {
+    return false; // default behaviour is never to roll
+};
+
+BaseRollingFileStream.prototype.roll = function(filename, callback) {
+    callback(); // default behaviour is not to do anything
+};
+