extract posix functions from std/os.zig to std/os/posix.zig

See #2380

CMakeLists.txt

@@ -621,9 +621,9 @@ set(ZIG_STD_FILES
     "os/time.zig"
     "os/uefi.zig"
     "os/wasi.zig"
-    "os/wasi/core.zig"
     "os/windows.zig"
     "os/windows/advapi32.zig"
+    "os/windows/errno.zig"
     "os/windows/error.zig"
     "os/windows/kernel32.zig"
     "os/windows/ntdll.zig"

doc/langref.html.in

@@ -195,7 +195,7 @@ const std = @import("std");
 
 pub fn main() !void {
     // If this program is run without stdout attached, exit with an error.
-    const stdout_file = try std.io.getStdOut();
+    const stdout_file = try std.os.File.stdout();
     // If this program encounters pipe failure when printing to stdout, exit
     // with an error.
     try stdout_file.write("Hello, world!\n");

example/hello_world/hello.zig

@@ -1,9 +1,5 @@
 const std = @import("std");
 
-pub fn main() !void {
-    // If this program is run without stdout attached, exit with an error.
-    const stdout_file = try std.io.getStdOut();
-    // If this program encounters pipe failure when printing to stdout, exit
-    // with an error.
-    try stdout_file.write("Hello, world!\n");
+pub fn main() void {
+    std.debug.warn("Hello, world!\n");
 }

example/hello_world/hello_libc.zig

@@ -2,13 +2,9 @@ const c = @cImport({
     // See https://github.com/ziglang/zig/issues/515
     @cDefine("_NO_CRT_STDIO_INLINE", "1");
     @cInclude("stdio.h");
-    @cInclude("string.h");
 });
 
-const msg = c"Hello, world!\n";
-
-export fn main(argc: c_int, argv: **u8) c_int {
-    if (c.printf(msg) != @intCast(c_int, c.strlen(msg))) return -1;
-
+export fn main(argc: c_int, argv: [*]?[*]u8) c_int {
+    c.fprintf(c.stderr, c"Hello, world!\n");
     return 0;
 }

std/c.zig

@@ -1,15 +1,24 @@
 const builtin = @import("builtin");
-const Os = builtin.Os;
+
+pub const is_the_target = builtin.link_libc;
 
 pub use switch (builtin.os) {
-    Os.linux => @import("c/linux.zig"),
-    Os.windows => @import("c/windows.zig"),
-    Os.macosx, Os.ios => @import("c/darwin.zig"),
-    Os.freebsd => @import("c/freebsd.zig"),
-    Os.netbsd => @import("c/netbsd.zig"),
+    .linux => @import("c/linux.zig"),
+    .windows => @import("c/windows.zig"),
+    .macosx, .ios, .tvos, .watchos => @import("c/darwin.zig"),
+    .freebsd => @import("c/freebsd.zig"),
+    .netbsd => @import("c/netbsd.zig"),
     else => struct {},
 };
 
+pub fn getErrno(rc: var) u12 {
+    if (rc == -1) {
+        return @intCast(u12, _errno().*);
+    } else {
+        return 0;
+    }
+}
+
 // TODO https://github.com/ziglang/zig/issues/265 on this whole file
 
 pub const FILE = @OpaqueType();
@@ -56,6 +65,7 @@ pub extern "c" fn nanosleep(rqtp: *const timespec, rmtp: ?*timespec) c_int;
 pub extern "c" fn setreuid(ruid: c_uint, euid: c_uint) c_int;
 pub extern "c" fn setregid(rgid: c_uint, egid: c_uint) c_int;
 pub extern "c" fn rmdir(path: [*]const u8) c_int;
+pub extern "c" fn getenv(name: [*]const u8) ?[*]u8;
 
 pub extern "c" fn aligned_alloc(alignment: usize, size: usize) ?*c_void;
 pub extern "c" fn malloc(usize) ?*c_void;

std/event/net.zig

@@ -89,14 +89,7 @@ pub const Server = struct {
                     },
                 };
             } else |err| switch (err) {
-                error.ProcessFdQuotaExceeded => {
-                    errdefer os.emfile_promise_queue.remove(&self.waiting_for_emfile_node);
-                    suspend {
-                        self.waiting_for_emfile_node = PromiseNode.init(@handle());
-                        os.emfile_promise_queue.append(&self.waiting_for_emfile_node);
-                    }
-                    continue;
-                },
+                error.ProcessFdQuotaExceeded => @panic("TODO handle this error"),
                 error.ConnectionAborted => continue,
 
                 error.FileDescriptorNotASocket => unreachable,

std/io.zig

@@ -18,23 +18,6 @@ const testing = std.testing;
 const is_posix = builtin.os != builtin.Os.windows;
 const is_windows = builtin.os == builtin.Os.windows;
 
-const GetStdIoErrs = os.WindowsGetStdHandleErrs;
-
-pub fn getStdErr() GetStdIoErrs!File {
-    const handle = if (is_windows) try os.windowsGetStdHandle(os.windows.STD_ERROR_HANDLE) else if (is_posix) os.posix.STDERR_FILENO else unreachable;
-    return File.openHandle(handle);
-}
-
-pub fn getStdOut() GetStdIoErrs!File {
-    const handle = if (is_windows) try os.windowsGetStdHandle(os.windows.STD_OUTPUT_HANDLE) else if (is_posix) os.posix.STDOUT_FILENO else unreachable;
-    return File.openHandle(handle);
-}
-
-pub fn getStdIn() GetStdIoErrs!File {
-    const handle = if (is_windows) try os.windowsGetStdHandle(os.windows.STD_INPUT_HANDLE) else if (is_posix) os.posix.STDIN_FILENO else unreachable;
-    return File.openHandle(handle);
-}
-
 pub const SeekableStream = @import("io/seekable_stream.zig").SeekableStream;
 pub const SliceSeekableInStream = @import("io/seekable_stream.zig").SliceSeekableInStream;
 pub const COutStream = @import("io/c_out_stream.zig").COutStream;
@@ -1116,10 +1099,12 @@ pub fn Deserializer(comptime endian: builtin.Endian, comptime packing: Packing,
         pub const Stream = InStream(Error);
 
         pub fn init(in_stream: *Stream) Self {
-            return Self{ .in_stream = switch (packing) {
-                .Bit => BitInStream(endian, Stream.Error).init(in_stream),
-                .Byte => in_stream,
-            } };
+            return Self{
+                .in_stream = switch (packing) {
+                    .Bit => BitInStream(endian, Stream.Error).init(in_stream),
+                    .Byte => in_stream,
+                },
+            };
         }
 
         pub fn alignToByte(self: *Self) void {
@@ -1325,10 +1310,12 @@ pub fn Serializer(comptime endian: builtin.Endian, comptime packing: Packing, co
         pub const Stream = OutStream(Error);
 
         pub fn init(out_stream: *Stream) Self {
-            return Self{ .out_stream = switch (packing) {
-                .Bit => BitOutStream(endian, Stream.Error).init(out_stream),
-                .Byte => out_stream,
-            } };
+            return Self{
+                .out_stream = switch (packing) {
+                    .Bit => BitOutStream(endian, Stream.Error).init(out_stream),
+                    .Byte => out_stream,
+                },
+            };
         }
 
         /// Flushes any unwritten bits to the stream