From f25404f2f2ebf75faef2523a7be28ecf437b7f5c Mon Sep 17 00:00:00 2001
From: Philippe Pittoli <karchnu@karchnu.fr>
Date: Sun, 1 May 2022 15:31:23 +0200
Subject: [PATCH] ls: fewer syscalls
---
src/ls.zig | 158 ++++++++++++++++++++++++++++++++++++++++++-----------
1 file changed, 125 insertions(+), 33 deletions(-)
diff --git a/src/ls.zig b/src/ls.zig
index fd1aaa2..8a66424 100644
--- a/src/ls.zig
+++ b/src/ls.zig
@@ -5,6 +5,9 @@ const path = std.fs.path;
const fs = std.fs;
const lib = @import("./lib.zig");
+const fmt = std.fmt;
+const depth = 3;
+
const Kind = std.fs.File.Kind;
const PermissionsUnix = std.fs.File.PermissionsUnix;
@@ -44,6 +47,7 @@ const Options = struct {
var options: Options = Options {};
fn print_stats(fpath: []const u8, stats: std.fs.File.Stat) void {
+ // lib.print("FS STATS: {}\n", .{stats});
// print kind (directory, file, pipe, etc.)
switch (stats.kind) {
.File => lib.print("-", .{}),
@@ -98,12 +102,7 @@ fn print_stats(fpath: []const u8, stats: std.fs.File.Stat) void {
return lib.print(" {s}\n", .{fpath});
}
-// mode = type (directory, file, symlink, etc.) + rights
-pub fn linuxstat_to_fsstat(st: std.os.linux.Stat) std.fs.File.StatError!std.fs.File.Stat {
- const atime = st.atime();
- const mtime = st.mtime();
- const ctime = st.ctime();
-
+fn fs_kind_from_linux_stat (st: std.os.linux.Stat) Kind {
const kind: Kind = if (builtin.os.tag == .wasi and !builtin.link_libc) switch (st.filetype) {
.BLOCK_DEVICE => Kind.BlockDevice,
.CHARACTER_DEVICE => Kind.CharacterDevice,
@@ -131,6 +130,18 @@ pub fn linuxstat_to_fsstat(st: std.os.linux.Stat) std.fs.File.StatError!std.fs.F
};
break :blk .Unknown;
};
+ return kind;
+}
+
+
+// mode = type (directory, file, symlink, etc.) + rights
+pub fn linuxstat_to_fsstat(st: std.os.linux.Stat) std.fs.File.StatError!std.fs.File.Stat {
+ // lib.print("LINUX STATS: {}\n", .{st});
+ const atime = st.atime();
+ const mtime = st.mtime();
+ const ctime = st.ctime();
+
+ const kind = fs_kind_from_linux_stat (st);
const stats = std.fs.File.Stat{
.inode = st.ino,
@@ -146,28 +157,113 @@ pub fn linuxstat_to_fsstat(st: std.os.linux.Stat) std.fs.File.StatError!std.fs.F
return stats;
}
+fn print_linux_stats (fpath: []const u8, stats: std.os.linux.Stat) !void {
+ var buffer = [_]u8 {0} ** (std.fs.MAX_PATH_BYTES + 100);
+ // var it: u16 = 0;
+ var fbs = std.io.fixedBufferStream(&buffer);
+ var writer = fbs.writer();
+
+ const fmtopts = fmt.FormatOptions{};
+ // try std.testing.expect(mem.eql(u8, fbs.getWritten(), "1234"));
+ // fbs.reset();
+
+ // print kind (directory, file, pipe, etc.)
+ const kind = fs_kind_from_linux_stat(stats);
+ switch (kind) {
+ .File => try fmt.formatType('-', "c", fmtopts, writer, depth),
+ .Directory => try fmt.formatType('d', "c", fmtopts, writer, depth),
+ .CharacterDevice => try fmt.formatType('c', "c", fmtopts, writer, depth),
+ .BlockDevice => try fmt.formatType('b', "c", fmtopts, writer, depth),
+ .NamedPipe => try fmt.formatType('p', "c", fmtopts, writer, depth),
+ .SymLink => try fmt.formatType('s', "c", fmtopts, writer, depth),
+ .UnixDomainSocket => try fmt.formatType('s', "c", fmtopts, writer, depth),
+ else => {
+ if (builtin.os.tag == .solaris) switch (kind) {
+ .Door => try fmt.formatType('D', "c", fmtopts, writer, depth), // TODO: what to print here?
+ .EventPort => try fmt.formatType('e', "c", fmtopts, writer, depth), // TODO: what to print here?
+ else => try fmt.formatType('?', "c", fmtopts, writer, depth),
+ };
+ },
+ }
+
+ // print rights
+ const perms = PermissionsUnix.unixNew(stats.mode);
+ const classes = [_]PermissionsUnix.Class {
+ PermissionsUnix.Class.user,
+ PermissionsUnix.Class.group,
+ PermissionsUnix.Class.other
+ };
+ const rights = [_]PermissionsUnix.Permission {
+ PermissionsUnix.Permission.read,
+ PermissionsUnix.Permission.write,
+ PermissionsUnix.Permission.execute
+ };
+ for (classes) |c| {
+ for (rights) |r| {
+ if (perms.unixHas(c,r)) {
+ switch(r) {
+ .read => try fmt.formatType('r', "c", fmtopts, writer, depth),
+ .write => try fmt.formatType('w', "c", fmtopts, writer, depth),
+ .execute => try fmt.formatType('x', "c", fmtopts, writer, depth),
+ }
+ }
+ else {
+ try fmt.formatType('-', "c", fmtopts, writer, depth);
+ }
+ }
+ }
+
+ // TODO: print user & group
+ try fmt.formatType('\t', "c", fmtopts, writer, depth);
+ try fmt.formatType(stats.uid, "", fmtopts, writer, depth);
+ try fmt.formatType('\t', "c", fmtopts, writer, depth);
+ try fmt.formatType(stats.gid, "", fmtopts, writer, depth);
+
+ // TODO: print size
+ // TODO: print date last write
+
+ // lib.print("{s}: {}\n", .{fpath, stats});
+
+ // std.mem.copy (u8, buffer[it..], fpath);
+ try fmt.formatType('\t', "c", fmtopts, writer, depth);
+ try fmt.formatType(fpath, "s", fmtopts, writer, depth);
+ try fmt.formatType('\n', "c", fmtopts, writer, depth);
+
+ return lib.print("{s}", .{fbs.getWritten()});
+}
+
+
fn print_file (fpath: []const u8) !void {
if (options.verbose == false) {
return lib.print("{s}\n", .{fpath});
}
- // First, try to open the file to stat it.
- var f: std.fs.File = undefined;
- f = switch (path.isAbsolute(fpath)) {
- true => std.fs.openFileAbsolute(fpath, .{.mode = .read_only}),
- else => cwd.openFile(fpath, .{.mode = .read_only}),
- } catch |err| switch(err) {
- error.AccessDenied => {
- lib.print("access denied\n", .{});
- // try to read the content of the parent directory
- return err;
- },
+ const dname = path.dirname(fpath);
+ var dir: fs.Dir = cwd.openDir(dname.?, .{}) catch |err| switch (err) {
+ error.AccessDenied => return lib.print("{s}: access denied\n", .{dname}),
else => return err,
};
- defer f.close();
- const stats = try f.stat();
- return print_stats (fpath, stats);
+ const bname = path.basename(fpath);
+ try print_file_in_dir (dir, bname);
+
+// // First, try to open the file to stat it.
+// var f: std.fs.File = undefined;
+// f = switch (path.isAbsolute(fpath)) {
+// true => std.fs.openFileAbsolute(fpath, .{.mode = .read_only}),
+// else => cwd.openFile(fpath, .{.mode = .read_only}),
+// } catch |err| switch(err) {
+// error.AccessDenied => {
+// lib.print("access denied\n", .{});
+// // try to read the content of the parent directory
+// return err;
+// },
+// else => return err,
+// };
+// defer f.close();
+//
+// const stats = try f.stat();
+// return print_stats (fpath, stats);
}
fn print_file_in_dir (dir: fs.Dir, entryname: []const u8) !void {
@@ -176,37 +272,33 @@ fn print_file_in_dir (dir: fs.Dir, entryname: []const u8) !void {
}
const stats = statFile(dir, entryname);
- return print_stats (entryname, try linuxstat_to_fsstat(stats));
+ // return print_stats (entryname, try linuxstat_to_fsstat(stats));
+ return try print_linux_stats (entryname, stats);
}
// TODO: improve this to use the fstatat syscall instead of making 2 syscalls here.
pub fn statFile(self: fs.Dir, sub_path: []const u8) std.os.linux.Stat {
var stat: std.os.linux.Stat = undefined;
- var t = [_:0]u8{0} ** 1000;
+ var t = [_:0]u8{0} ** std.fs.MAX_PATH_BYTES;
std.mem.copy (u8, t[0..], sub_path);
- var p = t[0..sub_path.len+1:0];
- // var p = sub_path[0..sub_path.len :0];
+ var p = t[0..sub_path.len+1:0]; // add a final \0 at the end of the string, and make the type checker happy
_ = std.os.linux.fstatat(self.fd, p, &stat, 0); // returns usize
return stat;
}
// Either print directory's content or file.
-fn print_element(fpath: []const u8) !void {
-
- // First:
- // if directory: try to open the directory.
- // else: try to open the parent directory.
-
+fn print_directory(fpath: []const u8) !void {
var dir: fs.Dir = cwd.openDir(fpath, .{.iterate = true}) catch |err| switch (err) {
error.AccessDenied => return lib.print("{s}: access denied\n", .{fpath}),
error.NotDir => {
+ // fpath is a simple file, just print the file infos
return try print_file(fpath);
},
else => return err,
};
- // fpath is a directory.
+ // fpath is a directory: print info on each file
var dir_it = dir.iterate();
while (try dir_it.next()) |entry| {
try print_file_in_dir (dir, entry.name);
@@ -232,13 +324,13 @@ pub fn ls() !void {
}
else {
nb_parameters += 1;
- try print_element(element);
+ try print_directory(element);
}
}
// case there were no parameter, print current directory
if (nb_parameters == 0) {
- try print_element(".");
+ try print_directory(".");
}
}