RoundToDirentry - Use existing directory data

lib/filesystem.js

@@ -333,7 +333,6 @@ function Inode(qidnumber)
     };
     this.caps = undefined;
     this.nlinks = 1;
-    this.dirent_offsets = undefined;
 
     //this.qid_type = 0;
     //this.qid_version = 0;
@@ -365,7 +364,6 @@ Inode.prototype.get_state = function()
     state[19] = this.qid.path;
     state[20] = this.caps;
     state[21] = this.nlinks;
-    state[22] = this.dirent_offsets;
     return state;
 };
 
@@ -393,7 +391,6 @@ Inode.prototype.set_state = function(state)
     this.qid.path = state[19];
     this.caps = state[20];
     this.nlinks = state[21];
-    this.dirent_offsets = state[22];
 };
 
 FS.prototype.CreateInode = function() {
@@ -825,8 +822,6 @@ FS.prototype.FillDirectory = function(dirid) {
     inode.size = size;
 
     var offset = 0x0;
-    inode.dirent_offsets = [offset];
-
     offset += marshall.Marshall(
         ["Q", "d", "b", "s"],
         [this.inodes[dirid].qid, 
@@ -834,7 +829,6 @@ FS.prototype.FillDirectory = function(dirid) {
         this.inodes[dirid].mode >> 12, 
         "."],
         data, offset);
-    inode.dirent_offsets.push(offset);
 
     offset += marshall.Marshall(
         ["Q", "d", "b", "s"],
@@ -843,7 +837,6 @@ FS.prototype.FillDirectory = function(dirid) {
         this.inodes[parentid].mode >> 12, 
         ".."],
         data, offset);
-    inode.dirent_offsets.push(offset);
 
     id = this.inodes[dirid].firstid;
     while(id != -1) {
@@ -854,7 +847,6 @@ FS.prototype.FillDirectory = function(dirid) {
         this.inodes[id].mode >> 12,
         this.inodes[id].name],
         data, offset);
-        this.inodes[dirid].dirent_offsets.push(offset);
         id = this.inodes[id].nextid;
     }
     inode.updatedir = false;
@@ -862,19 +854,24 @@ FS.prototype.FillDirectory = function(dirid) {
 
 FS.prototype.RoundToDirentry = function(dirid, offset_target)
 {
-    const offsets = this.GetInode(dirid).dirent_offsets;
+    const data = this.inodedata[dirid];
+    dbg_assert(data, `FS directory data for dirid=${dirid} should be generated`);
+    dbg_assert(data.length, "FS directory should have at least an entry");
 
-    dbg_assert(offsets, "9P direntry offsets should be cached");
-    dbg_assert(offsets[0] === 0, "9P first direntry offset should be zero");
-    dbg_assert(offset_target >= 0, "9P RoundToDirentry target offset should be non-negative");
-
-    let i = 0;
-    while(offsets[i] <= offset_target)
+    if(offset_target >= data.length)
     {
-        i++;
+        return data.length;
     }
 
-    return offsets[i - 1];
+    let offset = 0;
+    while(true)
+    {
+        const next_offset = marshall.Unmarshall(["Q", "d"], data, { offset })[1];
+        if(next_offset > offset_target) break;
+        offset = next_offset;
+    }
+
+    return offset;
 };
 
 

lib/marshall.js

@@ -111,6 +111,16 @@ marshall.Unmarshall = function(typelist, struct, state) {
                 }
                 output.push(str);
                 break;
+            case "Q":
+                state.offset = offset;
+                const qid = marshall.Unmarshall(["b", "w", "d"], struct, state);
+                offset = state.offset;
+                output.push({
+                    type: qid[0],
+                    version: qid[1],
+                    path: qid[2],
+                });
+                break;
             default:
                 message.Debug("Error in Unmarshall: Unknown type=" + typelist[i]);
                 break;