Merge pull request #6412 from kristoff-it/generalize-event-loop

Make os.zig not depend on the event loop

1 files changed, 315 insertions, 101 deletions

diff --git a/lib/std/event/loop.zig b/lib/std/event/loop.zig
index 13e704a8d3..2ed9f938d8 100644
--- a/lib/std/event/loop.zig
+++ b/lib/std/event/loop.zig
@@ -721,6 +721,50 @@ pub const Loop = struct {
         }
     }
 
+    /// ------- I/0 APIs -------
+    pub fn accept(
+        self: *Loop,
+        /// This argument is a socket that has been created with `socket`, bound to a local address
+        /// with `bind`, and is listening for connections after a `listen`.
+        sockfd: os.fd_t,
+        /// This argument is a pointer to a sockaddr structure.  This structure is filled in with  the
+        /// address  of  the  peer  socket, as known to the communications layer.  The exact format of the
+        /// address returned addr is determined by the socket's address  family  (see  `socket`  and  the
+        /// respective  protocol  man  pages).
+        addr: *os.sockaddr,
+        /// This argument is a value-result argument: the caller must initialize it to contain  the
+        /// size (in bytes) of the structure pointed to by addr; on return it will contain the actual size
+        /// of the peer address.
+        ///
+        /// The returned address is truncated if the buffer provided is too small; in this  case,  `addr_size`
+        /// will return a value greater than was supplied to the call.
+        addr_size: *os.socklen_t,
+        /// The following values can be bitwise ORed in flags to obtain different behavior:
+        /// * `SOCK_CLOEXEC`  - Set the close-on-exec (`FD_CLOEXEC`) flag on the new file descriptor.   See  the
+        ///   description  of the `O_CLOEXEC` flag in `open` for reasons why this may be useful.
+        flags: u32,
+    ) os.AcceptError!os.fd_t {
+        while (true) {
+            return os.accept(sockfd, addr, addr_size, flags | os.SOCK_NONBLOCK) catch |err| switch (err) {
+                error.WouldBlock => {
+                    self.waitUntilFdReadable(sockfd);
+                    continue;
+                },
+                else => return err,
+            };
+        }
+    }
+
+    pub fn connect(self: *Loop, sockfd: os.socket_t, sock_addr: *const os.sockaddr, len: os.socklen_t) os.ConnectError!void {
+        os.connect(sockfd, sock_addr, len) catch |err| switch (err) {
+            error.WouldBlock => {
+                self.waitUntilFdWritable(sockfd);
+                return os.getsockoptError(sockfd);
+            },
+            else => return err,
+        };
+    }
+
     /// Performs an async `os.open` using a separate thread.
     pub fn openZ(self: *Loop, file_path: [*:0]const u8, flags: u32, mode: os.mode_t) os.OpenError!os.fd_t {
         var req_node = Request.Node{
@@ -779,152 +823,309 @@ pub const Loop = struct {
 
     /// Performs an async `os.read` using a separate thread.
     /// `fd` must block and not return EAGAIN.
-    pub fn read(self: *Loop, fd: os.fd_t, buf: []u8) os.ReadError!usize {
-        var req_node = Request.Node{
-            .data = .{
-                .msg = .{
-                    .read = .{
-                        .fd = fd,
-                        .buf = buf,
-                        .result = undefined,
+    pub fn read(self: *Loop, fd: os.fd_t, buf: []u8, simulate_evented: bool) os.ReadError!usize {
+        if (simulate_evented) {
+            var req_node = Request.Node{
+                .data = .{
+                    .msg = .{
+                        .read = .{
+                            .fd = fd,
+                            .buf = buf,
+                            .result = undefined,
+                        },
                     },
+                    .finish = .{ .TickNode = .{ .data = @frame() } },
                 },
-                .finish = .{ .TickNode = .{ .data = @frame() } },
-            },
-        };
-        suspend {
-            self.posixFsRequest(&req_node);
+            };
+            suspend {
+                self.posixFsRequest(&req_node);
+            }
+            return req_node.data.msg.read.result;
+        } else {
+            while (true) {
+                return os.read(fd, buf) catch |err| switch (err) {
+                    error.WouldBlock => {
+                        self.waitUntilFdReadable(fd);
+                        continue;
+                    },
+                    else => return err,
+                };
+            }
         }
-        return req_node.data.msg.read.result;
     }
 
     /// Performs an async `os.readv` using a separate thread.
     /// `fd` must block and not return EAGAIN.
-    pub fn readv(self: *Loop, fd: os.fd_t, iov: []const os.iovec) os.ReadError!usize {
-        var req_node = Request.Node{
-            .data = .{
-                .msg = .{
-                    .readv = .{
-                        .fd = fd,
-                        .iov = iov,
-                        .result = undefined,
+    pub fn readv(self: *Loop, fd: os.fd_t, iov: []const os.iovec, simulate_evented: bool) os.ReadError!usize {
+        if (simulate_evented) {
+            var req_node = Request.Node{
+                .data = .{
+                    .msg = .{
+                        .readv = .{
+                            .fd = fd,
+                            .iov = iov,
+                            .result = undefined,
+                        },
                     },
+                    .finish = .{ .TickNode = .{ .data = @frame() } },
                 },
-                .finish = .{ .TickNode = .{ .data = @frame() } },
-            },
-        };
-        suspend {
-            self.posixFsRequest(&req_node);
+            };
+            suspend {
+                self.posixFsRequest(&req_node);
+            }
+            return req_node.data.msg.readv.result;
+        } else {
+            while (true) {
+                return os.readv(fd, iov) catch |err| switch (err) {
+                    error.WouldBlock => {
+                        self.waitUntilFdReadable(fd);
+                        continue;
+                    },
+                    else => return err,
+                };
+            }
         }
-        return req_node.data.msg.readv.result;
     }
 
     /// Performs an async `os.pread` using a separate thread.
     /// `fd` must block and not return EAGAIN.
-    pub fn pread(self: *Loop, fd: os.fd_t, buf: []u8, offset: u64) os.PReadError!usize {
-        var req_node = Request.Node{
-            .data = .{
-                .msg = .{
-                    .pread = .{
-                        .fd = fd,
-                        .buf = buf,
-                        .offset = offset,
-                        .result = undefined,
+    pub fn pread(self: *Loop, fd: os.fd_t, buf: []u8, offset: u64, simulate_evented: bool) os.PReadError!usize {
+        if (simulate_evented) {
+            var req_node = Request.Node{
+                .data = .{
+                    .msg = .{
+                        .pread = .{
+                            .fd = fd,
+                            .buf = buf,
+                            .offset = offset,
+                            .result = undefined,
+                        },
                     },
+                    .finish = .{ .TickNode = .{ .data = @frame() } },
                 },
-                .finish = .{ .TickNode = .{ .data = @frame() } },
-            },
-        };
-        suspend {
-            self.posixFsRequest(&req_node);
+            };
+            suspend {
+                self.posixFsRequest(&req_node);
+            }
+            return req_node.data.msg.pread.result;
+        } else {
+            while (true) {
+                return os.pread(fd, buf, offset) catch |err| switch (err) {
+                    error.WouldBlock => {
+                        self.waitUntilFdReadable(fd);
+                        continue;
+                    },
+                    else => return err,
+                };
+            }
         }
-        return req_node.data.msg.pread.result;
     }
 
     /// Performs an async `os.preadv` using a separate thread.
     /// `fd` must block and not return EAGAIN.
-    pub fn preadv(self: *Loop, fd: os.fd_t, iov: []const os.iovec, offset: u64) os.ReadError!usize {
-        var req_node = Request.Node{
-            .data = .{
-                .msg = .{
-                    .preadv = .{
-                        .fd = fd,
-                        .iov = iov,
-                        .offset = offset,
-                        .result = undefined,
+    pub fn preadv(self: *Loop, fd: os.fd_t, iov: []const os.iovec, offset: u64, simulate_evented: bool) os.ReadError!usize {
+        if (simulate_evented) {
+            var req_node = Request.Node{
+                .data = .{
+                    .msg = .{
+                        .preadv = .{
+                            .fd = fd,
+                            .iov = iov,
+                            .offset = offset,
+                            .result = undefined,
+                        },
                     },
+                    .finish = .{ .TickNode = .{ .data = @frame() } },
                 },
-                .finish = .{ .TickNode = .{ .data = @frame() } },
-            },
-        };
-        suspend {
-            self.posixFsRequest(&req_node);
+            };
+            suspend {
+                self.posixFsRequest(&req_node);
+            }
+            return req_node.data.msg.preadv.result;
+        } else {
+            while (true) {
+                return os.preadv(fd, iov, offset) catch |err| switch (err) {
+                    error.WouldBlock => {
+                        self.waitUntilFdReadable(fd);
+                        continue;
+                    },
+                    else => return err,
+                };
+            }
         }
-        return req_node.data.msg.preadv.result;
     }
 
     /// Performs an async `os.write` using a separate thread.
     /// `fd` must block and not return EAGAIN.
-    pub fn write(self: *Loop, fd: os.fd_t, bytes: []const u8) os.WriteError!usize {
-        var req_node = Request.Node{
-            .data = .{
-                .msg = .{
-                    .write = .{
-                        .fd = fd,
-                        .bytes = bytes,
-                        .result = undefined,
+    pub fn write(self: *Loop, fd: os.fd_t, bytes: []const u8, simulate_evented: bool) os.WriteError!usize {
+        if (simulate_evented) {
+            var req_node = Request.Node{
+                .data = .{
+                    .msg = .{
+                        .write = .{
+                            .fd = fd,
+                            .bytes = bytes,
+                            .result = undefined,
+                        },
                     },
+                    .finish = .{ .TickNode = .{ .data = @frame() } },
                 },
-                .finish = .{ .TickNode = .{ .data = @frame() } },
-            },
-        };
-        suspend {
-            self.posixFsRequest(&req_node);
+            };
+            suspend {
+                self.posixFsRequest(&req_node);
+            }
+            return req_node.data.msg.write.result;
+        } else {
+            while (true) {
+                return os.write(fd, bytes) catch |err| switch (err) {
+                    error.WouldBlock => {
+                        self.waitUntilFdWritable(fd);
+                        continue;
+                    },
+                    else => return err,
+                };
+            }
         }
-        return req_node.data.msg.write.result;
     }
 
     /// Performs an async `os.writev` using a separate thread.
     /// `fd` must block and not return EAGAIN.
-    pub fn writev(self: *Loop, fd: os.fd_t, iov: []const os.iovec_const) os.WriteError!usize {
-        var req_node = Request.Node{
-            .data = .{
-                .msg = .{
-                    .writev = .{
-                        .fd = fd,
-                        .iov = iov,
-                        .result = undefined,
+    pub fn writev(self: *Loop, fd: os.fd_t, iov: []const os.iovec_const, simulate_evented: bool) os.WriteError!usize {
+        if (simulate_evented) {
+            var req_node = Request.Node{
+                .data = .{
+                    .msg = .{
+                        .writev = .{
+                            .fd = fd,
+                            .iov = iov,
+                            .result = undefined,
+                        },
                     },
+                    .finish = .{ .TickNode = .{ .data = @frame() } },
                 },
-                .finish = .{ .TickNode = .{ .data = @frame() } },
-            },
-        };
-        suspend {
-            self.posixFsRequest(&req_node);
+            };
+            suspend {
+                self.posixFsRequest(&req_node);
+            }
+            return req_node.data.msg.writev.result;
+        } else {
+            while (true) {
+                return os.writev(fd, iov) catch |err| switch (err) {
+                    error.WouldBlock => {
+                        self.waitUntilFdWritable(fd);
+                        continue;
+                    },
+                    else => return err,
+                };
+            }
+        }
+    }
+
+    /// Performs an async `os.pwrite` using a separate thread.
+    /// `fd` must block and not return EAGAIN.
+    pub fn pwrite(self: *Loop, fd: os.fd_t, bytes: []const u8, offset: u64, simulate_evented: bool) os.PerformsWriteError!usize {
+        if (simulate_evented) {
+            var req_node = Request.Node{
+                .data = .{
+                    .msg = .{
+                        .pwrite = .{
+                            .fd = fd,
+                            .bytes = bytes,
+                            .offset = offset,
+                            .result = undefined,
+                        },
+                    },
+                    .finish = .{ .TickNode = .{ .data = @frame() } },
+                },
+            };
+            suspend {
+                self.posixFsRequest(&req_node);
+            }
+            return req_node.data.msg.pwrite.result;
+        } else {
+            while (true) {
+                return os.pwrite(fd, bytes, offset) catch |err| switch (err) {
+                    error.WouldBlock => {
+                        self.waitUntilFdWritable(fd);
+                        continue;
+                    },
+                    else => return err,
+                };
+            }
         }
-        return req_node.data.msg.writev.result;
     }
 
     /// Performs an async `os.pwritev` using a separate thread.
     /// `fd` must block and not return EAGAIN.
-    pub fn pwritev(self: *Loop, fd: os.fd_t, iov: []const os.iovec_const, offset: u64) os.WriteError!usize {
-        var req_node = Request.Node{
-            .data = .{
-                .msg = .{
-                    .pwritev = .{
-                        .fd = fd,
-                        .iov = iov,
-                        .offset = offset,
-                        .result = undefined,
+    pub fn pwritev(self: *Loop, fd: os.fd_t, iov: []const os.iovec_const, offset: u64, simulate_evented: bool) os.PWriteError!usize {
+        if (simulate_evented) {
+            var req_node = Request.Node{
+                .data = .{
+                    .msg = .{
+                        .pwritev = .{
+                            .fd = fd,
+                            .iov = iov,
+                            .offset = offset,
+                            .result = undefined,
+                        },
                     },
+                    .finish = .{ .TickNode = .{ .data = @frame() } },
                 },
-                .finish = .{ .TickNode = .{ .data = @frame() } },
-            },
-        };
-        suspend {
-            self.posixFsRequest(&req_node);
+            };
+            suspend {
+                self.posixFsRequest(&req_node);
+            }
+            return req_node.data.msg.pwritev.result;
+        } else {
+            while (true) {
+                return os.pwritev(fd, iov, offset) catch |err| switch (err) {
+                    error.WouldBlock => {
+                        self.waitUntilFdWritable(fd);
+                        continue;
+                    },
+                    else => return err,
+                };
+            }
+        }
+    }
+
+    pub fn sendto(
+        self: *Loop,
+        /// The file descriptor of the sending socket.
+        sockfd: os.fd_t,
+        /// Message to send.
+        buf: []const u8,
+        flags: u32,
+        dest_addr: ?*const os.sockaddr,
+        addrlen: os.socklen_t,
+    ) os.SendError!usize {
+        while (true) {
+            return os.sendto(sockfd, buf, flags, dest_addr, addrlen) catch |err| switch (err) {
+                error.WouldBlock => {
+                    self.waitUntilFdWritable(sockfd);
+                    continue;
+                },
+                else => return err,
+            };
+        }
+    }
+
+    pub fn recvfrom(
+        sockfd: os.fd_t,
+        buf: []u8,
+        flags: u32,
+        src_addr: ?*os.sockaddr,
+        addrlen: ?*os.socklen_t,
+    ) os.RecvFromError!usize {
+        while (true) {
+            return os.recvfrom(sockfd, buf, flags, src_addr, addrlen) catch |err| switch (err) {
+                error.WouldBlock => {
+                    self.waitUntilFdReadable(sockfd);
+                    continue;
+                },
+                else => return err,
+            };
         }
-        return req_node.data.msg.pwritev.result;
     }
 
     /// Performs an async `os.faccessatZ` using a separate thread.
@@ -1079,6 +1280,9 @@ pub const Loop = struct {
                     .writev => |*msg| {
                         msg.result = os.writev(msg.fd, msg.iov);
                     },
+                    .pwrite => |*msg| {
+                        msg.result = os.pwrite(msg.fd, msg.bytes, msg.offset);
+                    },
                     .pwritev => |*msg| {
                         msg.result = os.pwritev(msg.fd, msg.iov, msg.offset);
                     },
@@ -1148,6 +1352,7 @@ pub const Loop = struct {
             readv: ReadV,
             write: Write,
             writev: WriteV,
+            pwrite: PWrite,
             pwritev: PWriteV,
             pread: PRead,
             preadv: PReadV,
@@ -1191,6 +1396,15 @@ pub const Loop = struct {
                 pub const Error = os.WriteError;
             };
 
+            pub const PWrite = struct {
+                fd: os.fd_t,
+                bytes: []const u8,
+                offset: usize,
+                result: Error!usize,
+
+                pub const Error = os.PWriteError;
+            };
+
             pub const PWriteV = struct {
                 fd: os.fd_t,
                 iov: []const os.iovec_const,