Review fixes

client/src/index.js

@@ -118,7 +118,9 @@ function createFS(options) {
   var autoSync;
   var pathCache;
 
-  // Path needed to be upstreamed during a downstream sync
+  // Path that needs to be used for an upstream sync
+  // to sync files that were determined to be more 
+  // up-to-date on the client during a downstream sync
   var upstreamPath;
 
   // State of the sync connection

client/src/message-handler.js

@@ -137,6 +137,9 @@ function handleResponse(syncManager, data) {
             return callback(err);
           }
 
+          // Non-existent paths (usually due to renames or
+          // deletes that are included in the syncedPaths)
+          // cannot be stamped with a checksum
           return callback();
         }
 
@@ -149,19 +152,14 @@ function handleResponse(syncManager, data) {
             return callback(err);
           }
 
-          fsUtils.setChecksum(fs, path, checksum, function(err) {
-            if(err) {
-              return callback(err);
-            }
-
-            callback();
-          });
+          fsUtils.setChecksum(fs, path, checksum, callback);
         });
       });
     }
 
-    // Store the checksums of the upstream synced files
-    // as xattrs on the file
+    // As soon as an upstream sync happens, the files synced
+    // become the last synced versions and must be stamped
+    // with their checksums to version them
     async.eachSeries(syncedPaths, stampChecksum, function(err) {
       if(err) {
         return onError(syncManager, err);

lib/fs-utils.js

@@ -59,22 +59,10 @@ function fremoveUnsynced(fs, fd, callback) {
 
 // Set the unsynced metadata for a path
 function setUnsynced(fs, path, callback) {
-  fs.setxattr(path, constants.attributes.unsynced, Date.now(), function(err) {
-    if(err) {
-      return callback(err);
-    }
-
-    callback();
-  });
+  fs.setxattr(path, constants.attributes.unsynced, Date.now(), callback);
 }
 function fsetUnsynced(fs, fd, callback) {
-  fs.fsetxattr(fd, constants.attributes.unsynced, Date.now(), function(err) {
-    if(err) {
-      return callback(err);
-    }
-
-    callback();
-  });
+  fs.fsetxattr(fd, constants.attributes.unsynced, Date.now(), callback);
 }
 
 // Get the unsynced metadata for a path
@@ -119,22 +107,10 @@ function fremoveChecksum(fs, fd, callback) {
 
 // Set the Checksum metadata for a path
 function setChecksum(fs, path, checksum, callback) {
-  fs.setxattr(path, constants.attributes.checksum, checksum, function(err) {
-    if(err) {
-      return callback(err);
-    }
-
-    callback();
-  });
+  fs.setxattr(path, constants.attributes.checksum, checksum, callback);
 }
 function fsetChecksum(fs, fd, checksum, callback) {
-  fs.fsetxattr(fd, constants.attributes.checksum, checksum, function(err) {
-    if(err) {
-      return callback(err);
-    }
-
-    callback();
-  });
+  fs.fsetxattr(fd, constants.attributes.checksum, checksum, callback);
 }
 
 // Get the Checksum metadata for a path

lib/rsync/patch.js

@@ -193,7 +193,7 @@ module.exports = function patch(fs, path, diffList, options, callback) {
         }
 
         // If the file was modified before the
-        // diffNode's modified time, it is outdated
+        // diffNode's modified time, the file is outdated
         // and needs to be patched
         if(stats.mtime <= diffNode.modified) {
           return applyPatch(getPatchedData(data));

lib/rsync/rsync-utils.js

@@ -203,7 +203,10 @@ function roll(data, checksums, blockSize) {
   return results;
 }
 
-// RSync function to calculate checksums
+// Rsync function to calculate checksums for 
+// a file by dividing it into blocks of data
+// whose size is passed in and checksuming each
+// block of data
 function blockChecksums(fs, path, size, callback) {
   var cache = {};
 
@@ -249,6 +252,7 @@ function blockChecksums(fs, path, size, callback) {
 }
 
 // Generate the MD5 hash for the data of a file
+// in its entirety
 function getChecksum(fs, path, callback) {
   fs.readFile(path, function(err, data) {
     if(!err) {