std: file system watching for linux

3 files changed, 124 insertions, 4 deletions

diff --git a/std/os/file.zig b/std/os/file.zig
index c402aa0522..24c3128350 100644
--- a/std/os/file.zig
+++ b/std/os/file.zig
@@ -29,7 +29,6 @@ pub const File = struct {
 
     /// `path` needs to be copied in memory to add a null terminating byte, hence the allocator.
     /// Call close to clean up.
-    /// TODO deprecated, just use open
     pub fn openRead(allocator: *mem.Allocator, path: []const u8) OpenError!File {
         if (is_posix) {
             const flags = posix.O_LARGEFILE | posix.O_RDONLY;
@@ -51,7 +50,6 @@ pub const File = struct {
     }
 
     /// Calls `openWriteMode` with os.File.default_mode for the mode.
-    /// TODO deprecated, just use open
     pub fn openWrite(allocator: *mem.Allocator, path: []const u8) OpenError!File {
         return openWriteMode(allocator, path, os.File.default_mode);
     }
@@ -60,7 +58,6 @@ pub const File = struct {
     /// If a file already exists in the destination it will be truncated.
     /// `path` needs to be copied in memory to add a null terminating byte, hence the allocator.
     /// Call close to clean up.
-    /// TODO deprecated, just use open
     pub fn openWriteMode(allocator: *mem.Allocator, path: []const u8, file_mode: Mode) OpenError!File {
         if (is_posix) {
             const flags = posix.O_LARGEFILE | posix.O_WRONLY | posix.O_CREAT | posix.O_CLOEXEC | posix.O_TRUNC;
@@ -85,7 +82,6 @@ pub const File = struct {
     /// If a file already exists in the destination this returns OpenError.PathAlreadyExists
     /// `path` needs to be copied in memory to add a null terminating byte, hence the allocator.
     /// Call close to clean up.
-    /// TODO deprecated, just use open
     pub fn openWriteNoClobber(allocator: *mem.Allocator, path: []const u8, file_mode: Mode) OpenError!File {
         if (is_posix) {
             const flags = posix.O_LARGEFILE | posix.O_WRONLY | posix.O_CREAT | posix.O_CLOEXEC | posix.O_EXCL;
diff --git a/std/os/index.zig b/std/os/index.zig
index 727c71c435..943e1259b3 100644
--- a/std/os/index.zig
+++ b/std/os/index.zig
@@ -310,6 +310,29 @@ pub fn posixWrite(fd: i32, bytes: []const u8) !void {
     }
 }
 
+pub fn posix_pwritev(fd: i32, iov: [*]const posix.iovec_const, count: usize, offset: u64) PosixWriteError!void {
+    while (true) {
+        const rc = posix.pwritev(fd, iov, count, offset);
+        const err = posix.getErrno(rc);
+        switch (err) {
+            0 => return,
+            posix.EINTR => continue,
+            posix.EINVAL => unreachable,
+            posix.EFAULT => unreachable,
+            posix.EAGAIN => return PosixWriteError.WouldBlock,
+            posix.EBADF => return PosixWriteError.FileClosed,
+            posix.EDESTADDRREQ => return PosixWriteError.DestinationAddressRequired,
+            posix.EDQUOT => return PosixWriteError.DiskQuota,
+            posix.EFBIG => return PosixWriteError.FileTooBig,
+            posix.EIO => return PosixWriteError.InputOutput,
+            posix.ENOSPC => return PosixWriteError.NoSpaceLeft,
+            posix.EPERM => return PosixWriteError.AccessDenied,
+            posix.EPIPE => return PosixWriteError.BrokenPipe,
+            else => return unexpectedErrorPosix(err),
+        }
+    }
+}
+
 pub const PosixOpenError = error{
     OutOfMemory,
     AccessDenied,
@@ -2913,3 +2936,44 @@ pub fn bsdKEvent(
         }
     }
 }
+
+pub fn linuxINotifyInit1(flags: u32) !i32 {
+    const rc = linux.inotify_init1(flags);
+    const err = posix.getErrno(rc);
+    switch (err) {
+        0 => return @intCast(i32, rc),
+        posix.EINVAL => unreachable,
+        posix.EMFILE => return error.ProcessFdQuotaExceeded,
+        posix.ENFILE => return error.SystemFdQuotaExceeded,
+        posix.ENOMEM => return error.SystemResources,
+        else => return unexpectedErrorPosix(err),
+    }
+}
+
+pub fn linuxINotifyAddWatchC(inotify_fd: i32, pathname: [*]const u8, mask: u32) !i32 {
+    const rc = linux.inotify_add_watch(inotify_fd, pathname, mask);
+    const err = posix.getErrno(rc);
+    switch (err) {
+        0 => return @intCast(i32, rc),
+        posix.EACCES => return error.AccessDenied,
+        posix.EBADF => unreachable,
+        posix.EFAULT => unreachable,
+        posix.EINVAL => unreachable,
+        posix.ENAMETOOLONG => return error.NameTooLong,
+        posix.ENOENT => return error.FileNotFound,
+        posix.ENOMEM => return error.SystemResources,
+        posix.ENOSPC => return error.UserResourceLimitReached,
+        else => return unexpectedErrorPosix(err),
+    }
+}
+
+pub fn linuxINotifyRmWatch(inotify_fd: i32, wd: i32) !void {
+    const rc = linux.inotify_rm_watch(inotify_fd, wd);
+    const err = posix.getErrno(rc);
+    switch (err) {
+        0 => return rc,
+        posix.EBADF => unreachable,
+        posix.EINVAL => unreachable,
+        else => unreachable,
+    }
+}
diff --git a/std/os/linux/index.zig b/std/os/linux/index.zig
index cf68e03ff0..2b0e5e8288 100644
--- a/std/os/linux/index.zig
+++ b/std/os/linux/index.zig
@@ -567,6 +567,37 @@ pub const MNT_DETACH = 2;
 pub const MNT_EXPIRE = 4;
 pub const UMOUNT_NOFOLLOW = 8;
 
+pub const IN_CLOEXEC = O_CLOEXEC;
+pub const IN_NONBLOCK = O_NONBLOCK;
+
+pub const IN_ACCESS = 0x00000001;
+pub const IN_MODIFY = 0x00000002;
+pub const IN_ATTRIB = 0x00000004;
+pub const IN_CLOSE_WRITE = 0x00000008;
+pub const IN_CLOSE_NOWRITE = 0x00000010;
+pub const IN_CLOSE = IN_CLOSE_WRITE | IN_CLOSE_NOWRITE;
+pub const IN_OPEN = 0x00000020;
+pub const IN_MOVED_FROM = 0x00000040;
+pub const IN_MOVED_TO = 0x00000080;
+pub const IN_MOVE = IN_MOVED_FROM | IN_MOVED_TO;
+pub const IN_CREATE = 0x00000100;
+pub const IN_DELETE = 0x00000200;
+pub const IN_DELETE_SELF = 0x00000400;
+pub const IN_MOVE_SELF = 0x00000800;
+pub const IN_ALL_EVENTS = 0x00000fff;
+
+pub const IN_UNMOUNT = 0x00002000;
+pub const IN_Q_OVERFLOW = 0x00004000;
+pub const IN_IGNORED = 0x00008000;
+
+pub const IN_ONLYDIR = 0x01000000;
+pub const IN_DONT_FOLLOW = 0x02000000;
+pub const IN_EXCL_UNLINK = 0x04000000;
+pub const IN_MASK_ADD = 0x20000000;
+
+pub const IN_ISDIR = 0x40000000;
+pub const IN_ONESHOT = 0x80000000;
+
 pub const S_IFMT = 0o170000;
 
 pub const S_IFDIR = 0o040000;
@@ -704,6 +735,18 @@ pub fn getdents(fd: i32, dirp: [*]u8, count: usize) usize {
     return syscall3(SYS_getdents, @intCast(usize, fd), @ptrToInt(dirp), count);
 }
 
+pub fn inotify_init1(flags: u32) usize {
+    return syscall1(SYS_inotify_init1, flags);
+}
+
+pub fn inotify_add_watch(fd: i32, pathname: [*]const u8, mask: u32) usize {
+    return syscall3(SYS_inotify_add_watch, @intCast(usize, fd), @ptrToInt(pathname), mask);
+}
+
+pub fn inotify_rm_watch(fd: i32, wd: i32) usize {
+    return syscall2(SYS_inotify_rm_watch, @intCast(usize, fd), @intCast(usize, wd));
+}
+
 pub fn isatty(fd: i32) bool {
     var wsz: winsize = undefined;
     return syscall3(SYS_ioctl, @intCast(usize, fd), TIOCGWINSZ, @ptrToInt(&wsz)) == 0;
@@ -750,6 +793,10 @@ pub fn preadv(fd: i32, iov: [*]const iovec, count: usize, offset: u64) usize {
     return syscall4(SYS_preadv, @intCast(usize, fd), @ptrToInt(iov), count, offset);
 }
 
+pub fn pwritev(fd: i32, iov: [*]const iovec_const, count: usize, offset: u64) usize {
+    return syscall4(SYS_pwritev, @intCast(usize, fd), @ptrToInt(iov), count, offset);
+}
+
 // TODO https://github.com/ziglang/zig/issues/265
 pub fn rmdir(path: [*]const u8) usize {
     return syscall1(SYS_rmdir, @ptrToInt(path));
@@ -1068,6 +1115,11 @@ pub const iovec = extern struct {
     iov_len: usize,
 };
 
+pub const iovec_const = extern struct {
+    iov_base: [*]const u8,
+    iov_len: usize,
+};
+
 pub fn getsockname(fd: i32, noalias addr: *sockaddr, noalias len: *socklen_t) usize {
     return syscall3(SYS_getsockname, @intCast(usize, fd), @ptrToInt(addr), @ptrToInt(len));
 }
@@ -1376,6 +1428,14 @@ pub fn capset(hdrp: *cap_user_header_t, datap: *const cap_user_data_t) usize {
     return syscall2(SYS_capset, @ptrToInt(hdrp), @ptrToInt(datap));
 }
 
+pub const inotify_event = extern struct {
+    wd: i32,
+    mask: u32,
+    cookie: u32,
+    len: u32,
+    //name: [?]u8,
+};
+
 test "import" {
     if (builtin.os == builtin.Os.linux) {
         _ = @import("test.zig");