Merge pull request #7 from divyenduz/fix_symlinks_and_links

fix: symlinks and links

.gitignore

@@ -4,6 +4,8 @@
 tsconfig.tsbuildinfo
 img.png
 
+*.log
+
 # See http://help.github.com/ignore-files/ for more about ignoring files.
 
 # compiled output

packages/common/index.ts

@@ -1,20 +1,21 @@
-import { File } from "@prisma/client";
+import { File, Link } from "@prisma/client";
 
 type FileType = "file" | "dir" | "symlink";
 
-type Result<T> =
-  | {
+type Result<T, K extends string = "file"> =
+  | ({
       status: "ok";
-      file: T;
-    }
+    } & { [P in K]: T })
   | {
       status: "not_found";
     };
 
 // TODO: bump this based on the latest state of the actual backend!
 
 export interface Backend {
-  getFiles: (dir: string) => Promise<File[]>;
+  // TODO: use resule
+  getLinks: (dir: string) => Promise<Link[]>;
+  getLink: (dir: string) => Promise<Result<Link, "link">>;
   getFile: (filepath: string) => Promise<Result<File>>;
 
   createFile: (
@@ -23,16 +24,13 @@ export interface Backend {
     mode: number,
     uid: number,
     gid: number,
-    targetId: number
-  ) => Promise<Result<File>>;
-
-  writeFile: (
-    filepath: string,
-    uid: number,
-    gid: number
+    targetPath: string
   ) => Promise<Result<File>>;
 
-  deleteFile: (filepath: string) => Promise<Result<File>>;
-  renameFile: (srcPath: string, destPath: string) => Promise<Result<File>>;
+  deleteFile: (filepath: string) => Promise<Result<number, "count">>;
+  renameFile: (
+    srcPath: string,
+    destPath: string
+  ) => Promise<Result<Link, "link">>;
   updateMode: (filepath: string, mode: number) => Promise<Result<File>>;
 }

packages/fuse-client/syscalls/getattr.ts

@@ -6,23 +6,24 @@ export const getattr: (backend: SQLiteBackend) => MountOptions["getattr"] = (
   backend
 ) => {
   return async (path, cb) => {
-    console.log("getattr(%s)", path);
+    console.info("getattr(%s)", path);
     const r = await backend.getFile(path);
-
     await match(r)
       .with({ status: "ok" }, async (r) => {
         const rSize = await backend.getFileSize(path);
         if (rSize.status !== "ok") {
           cb(fuse.ENOENT);
           return;
         }
-
+        const rNlinks = await backend.getFileNLinks(path);
         const { mtime, atime, ctime, mode } = r.file;
         cb(0, {
           mtime,
           atime,
           ctime,
-          nlink: 1,
+          blocks: 1,
+          ino: r.file.id,
+          nlink: rNlinks.nLinks?.length || 1,
           size: rSize.size,
           mode: mode,
           // TODO: enable posix mode where real uid/gid are returned

packages/fuse-client/syscalls/init.ts

@@ -6,7 +6,7 @@ export const init: (backend: SQLiteBackend) => MountOptions["init"] = (
   backend
 ) => {
   return async (cb) => {
-    console.log("init");
+    console.info("init");
 
     //@ts-expect-error fix types
     const context = fuse.context();

packages/fuse-client/syscalls/link.ts

@@ -1,14 +1,25 @@
 import { SQLiteBackend } from "@zoid-fs/sqlite-backend";
-import { MountOptions } from "@zoid-fs/node-fuse-bindings";
-import { symlink } from "./symlink";
+import fuse, { MountOptions } from "@zoid-fs/node-fuse-bindings";
+import { match } from "ts-pattern";
 
 export const link: (backend: SQLiteBackend) => MountOptions["link"] = (
   backend
 ) => {
-  return async (src, dest, cb) => {
-    console.log("link(%s, %s)", src, dest);
-    //@ts-expect-error fix types
-    // TODO: implement link properly
-    symlink(backend)(src, dest, cb);
+  return async (srcPath, destPath, cb) => {
+    console.info("link(%s, %s)", srcPath, destPath);
+
+    // TODO: throw if destination doesn't exist
+
+    // TODO: double check if mode for link is correct
+    // https://unix.stackexchange.com/questions/193465/what-file-mode-is-a-link
+    const r = await backend.createLink(srcPath, destPath);
+    match(r)
+      .with({ status: "ok" }, () => {
+        cb(0);
+      })
+      .with({ status: "not_found" }, () => {
+        cb(fuse.ENOENT);
+      })
+      .exhaustive();
   };
 };

packages/fuse-client/syscalls/open.ts

@@ -6,7 +6,7 @@ export const open: (backend: SQLiteBackend) => MountOptions["open"] = (
   backend
 ) => {
   return async (path, flags, cb) => {
-    console.log("open(%s, %d)", path, flags);
+    console.info("open(%s, %d)", path, flags);
     const r = await backend.getFile(path);
 
     match(r)

packages/fuse-client/syscalls/opendir.ts

@@ -6,7 +6,7 @@ export const opendir: (backend: SQLiteBackend) => MountOptions["opendir"] = (
   backend
 ) => {
   return async (path, flags, cb) => {
-    console.log("opendir(%s, %d)", path, flags);
+    console.info("opendir(%s, %d)", path, flags);
 
     if (path === "/") {
       cb(0, 42); // TODO: Universal FD for root dir, it should probably be in the database as bootstrap

packages/fuse-client/syscalls/readdir.ts

@@ -10,8 +10,8 @@ export const readdir: (backend: SQLiteBackend) => MountOptions["readdir"] = (
     // TODO: figure out how are these directories in output of ls -la
     const dotDirs = [".", ".."];
 
-    const files = await backend.getFiles(path);
-    const fileNames = dotDirs.concat(files.map((file) => file.name));
+    const links = await backend.getLinks(path);
+    const fileNames = dotDirs.concat(links.map((link) => link.name));
 
     return cb(0, fileNames);
   };

packages/fuse-client/syscalls/readlink.ts

@@ -6,16 +6,23 @@ export const readlink: (backend: SQLiteBackend) => MountOptions["readlink"] = (
   backend
 ) => {
   return async (path, cb) => {
-    console.log("readlink(%s)", path);
-    const r = await backend.getFile(path);
-    match(r)
-      .with({ status: "ok" }, (r) => {
-        cb(0, r.file.name);
-      })
-      .with({ status: "not_found" }, () => {
-        //@ts-expect-error fix types, what to do if readlink fails?
-        cb(fuse.ENOENT);
-      })
-      .exhaustive();
+    console.info("readlink(%s)", path);
+    try {
+      const r = await backend.getLink(path);
+      match(r)
+        .with({ status: "ok" }, (r) => {
+          cb(0, r.link.targetPath);
+        })
+        .with({ status: "not_found" }, () => {
+          //@ts-expect-error fix types, what to do if readlink fails?
+          cb(fuse.ENOENT);
+        })
+        .exhaustive();
+    } catch (e) {
+      console.error(e);
+      return {
+        status: "not_found" as const,
+      };
+    }
   };
 };

packages/fuse-client/syscalls/symlink.ts

@@ -1,17 +1,25 @@
 import { SQLiteBackend } from "@zoid-fs/sqlite-backend";
 import fuse, { MountOptions } from "@zoid-fs/node-fuse-bindings";
 import { match } from "ts-pattern";
+import { constants } from "fs";
+import path from "path";
 
 export const symlink: (backend: SQLiteBackend) => MountOptions["symlink"] = (
   backend
 ) => {
   return async (srcPath, destPath, cb) => {
-    console.log("symlink(%s, %s)", srcPath, destPath);
+    console.info("symlink(%s, %s)", srcPath, destPath);
 
-    const targetFile = await backend.getFile(srcPath);
-    console.log({ targetFile });
-    if (targetFile.status === "not_found") {
-      cb(fuse.ENOENT);
+    const parsedDestPath = path.parse(destPath);
+    // Note: actually 255 as per the spec but we get an extra / in the dest path
+    if (parsedDestPath.base.length > 255) {
+      cb(fuse.ENAMETOOLONG);
+      return;
+    }
+
+    // Note: actually 1023 as per the spec but we get an extra / in the dest path
+    if (srcPath.length > 1023 || destPath.length > 1023) {
+      cb(fuse.ENAMETOOLONG);
       return;
     }
 
@@ -24,10 +32,10 @@ export const symlink: (backend: SQLiteBackend) => MountOptions["symlink"] = (
     const r = await backend.createFile(
       destPath,
       "symlink",
-      33188,
+      constants.S_IFLNK,
       uid,
       gid,
-      targetFile.file.id
+      srcPath
     );
     match(r)
       .with({ status: "ok" }, () => {