convert all to use sys/linux over sys/unix; new implementations for pipe, process and env

core/os/os2/file_linux.odin

@@ -1,39 +1,60 @@
 //+private
 package os2
 
-import "base:runtime"
 import "core:io"
 import "core:time"
-import "core:sys/unix"
-
-INVALID_HANDLE :: -1
-
-_O_RDONLY    :: 0o00000000
-_O_WRONLY    :: 0o00000001
-_O_RDWR      :: 0o00000002
-_O_CREAT     :: 0o00000100
-_O_EXCL      :: 0o00000200
-_O_NOCTTY    :: 0o00000400
-_O_TRUNC     :: 0o00001000
-_O_APPEND    :: 0o00002000
-_O_NONBLOCK  :: 0o00004000
-_O_LARGEFILE :: 0o00100000
-_O_DIRECTORY :: 0o00200000
-_O_NOFOLLOW  :: 0o00400000
-_O_SYNC      :: 0o04010000
-_O_CLOEXEC   :: 0o02000000
-_O_PATH      :: 0o10000000
-
-_AT_FDCWD :: -100
-
-_CSTRING_NAME_HEAP_THRESHOLD :: 512
+import "base:runtime"
+import "core:sys/linux"
 
 _File :: struct {
 	name: string,
-	fd: int,
+	fd: linux.Fd,
 	allocator: runtime.Allocator,
 }
 
+_stdin : File = {
+	impl = {
+		name = "/proc/self/fd/0",
+		fd = 0,
+		allocator = _file_allocator(),
+	},
+	stream = {
+		procedure = _file_stream_proc,
+	},
+}
+_stdout : File = {
+	impl = {
+		name = "/proc/self/fd/1",
+		fd = 1,
+		allocator = _file_allocator(),
+	},
+	stream = {
+		procedure = _file_stream_proc,
+	},
+}
+_stderr : File = {
+	impl = {
+		name = "/proc/self/fd/2",
+		fd = 2,
+		allocator = _file_allocator(),
+	},
+	stream = {
+		procedure = _file_stream_proc,
+	},
+}
+
+@init
+_standard_stream_init :: proc() {
+	// cannot define these manually because cyclic reference
+	_stdin.stream.data = &_stdin
+	_stdout.stream.data = &_stdout
+	_stderr.stream.data = &_stderr
+}
+
+_file_allocator :: proc() -> runtime.Allocator {
+	return heap_allocator()
+}
+
 _open :: proc(name: string, flags: File_Flags, perm: File_Mode) -> (f: ^File, err: Error) {
 	TEMP_ALLOCATOR_GUARD()
 	name_cstr := temp_cstring(name) or_return
@@ -41,40 +62,48 @@ _open :: proc(name: string, flags: File_Flags, perm: File_Mode) -> (f: ^File, er
 	// Just default to using O_NOCTTY because needing to open a controlling
 	// terminal would be incredibly rare. This has no effect on files while
 	// allowing us to open serial devices.
-	flags_i: int = _O_NOCTTY
+	sys_flags: linux.Open_Flags = {.NOCTTY}
 	switch flags & O_RDONLY|O_WRONLY|O_RDWR {
-	case O_RDONLY: flags_i = _O_RDONLY
-	case O_WRONLY: flags_i = _O_WRONLY
-	case O_RDWR:   flags_i = _O_RDWR
+	case O_RDONLY:
+	case O_WRONLY: sys_flags += {.WRONLY}
+	case O_RDWR:   sys_flags += {.RDWR}
 	}
 
-	if .Append        in flags { flags_i |= _O_APPEND  }
-	if .Create        in flags { flags_i |= _O_CREAT   }
-	if .Excl          in flags { flags_i |= _O_EXCL    }
-	if .Sync          in flags { flags_i |= _O_SYNC    }
-	if .Trunc         in flags { flags_i |= _O_TRUNC   }
-	if .Close_On_Exec in flags { flags_i |= _O_CLOEXEC }
+	if .Append in flags        { sys_flags += {.APPEND} }
+	if .Create in flags        { sys_flags += {.CREAT} }
+	if .Excl in flags          { sys_flags += {.EXCL} }
+	if .Sync in flags          { sys_flags += {.DSYNC} }
+	if .Trunc in flags         { sys_flags += {.TRUNC} }
+	if .Close_On_Exec in flags { sys_flags += {.CLOEXEC} }
 
-	fd := unix.sys_open(name_cstr, flags_i, uint(perm))
-	if fd < 0 {
-		return nil, _get_platform_error(fd)
+	fd, errno := linux.open(name_cstr, sys_flags, transmute(linux.Mode)(u32(perm)))
+	if errno != .NONE {
+		return nil, _get_platform_error(errno)
 	}
 
 	return _new_file(uintptr(fd), name), nil
 }
 
-_new_file :: proc(fd: uintptr, _: string) -> ^File {
+_new_file :: proc(fd: uintptr, _: string = "") -> ^File {
 	file := new(File, file_allocator())
-	file.impl.fd = int(fd)
-	file.impl.allocator = file_allocator()
-	file.impl.name = _get_full_path(file.impl.fd, file.impl.allocator)
-	file.stream = {
-		data = file,
-		procedure = _file_stream_proc,
-	}
+	_construct_file(file, fd, "")
 	return file
 }
 
+_construct_file :: proc(file: ^File, fd: uintptr, _: string = "") {
+	file^ = {
+		impl = {
+			fd = linux.Fd(fd),
+			allocator = file_allocator(),
+			name = _get_full_path(file.impl.fd, file.impl.allocator),
+		},
+		stream = {
+			data = file,
+			procedure = _file_stream_proc,
+		},
+	}
+}
+
 _destroy :: proc(f: ^File) -> Error {
 	if f == nil {
 		return nil
@@ -86,12 +115,15 @@ _destroy :: proc(f: ^File) -> Error {
 
 
 _close :: proc(f: ^File) -> Error {
-	if f != nil {
-		res := unix.sys_close(f.impl.fd)
-		_destroy(f)
-		return _ok_or_error(res)
+	if f == nil {
+		return nil
 	}
-	return nil
+	errno := linux.close(f.impl.fd)
+	if errno == .EBADF { // avoid possible double free
+		return _get_platform_error(errno)
+	}
+	_destroy(f)
+	return _get_platform_error(errno)
 }
 
 _fd :: proc(f: ^File) -> uintptr {
@@ -106,20 +138,32 @@ _name :: proc(f: ^File) -> string {
 }
 
 _seek :: proc(f: ^File, offset: i64, whence: io.Seek_From) -> (ret: i64, err: Error) {
-	res := unix.sys_lseek(f.impl.fd, offset, int(whence))
-	if res < 0 {
-		return -1, _get_platform_error(int(res))
+	n, errno := linux.lseek(f.impl.fd, offset, linux.Seek_Whence(whence))
+	if errno != .NONE {
+		return -1, _get_platform_error(errno)
 	}
-	return res, nil
+	return n, nil
 }
 
 _read :: proc(f: ^File, p: []byte) -> (i64, Error) {
 	if len(p) == 0 {
 		return 0, nil
 	}
-	n := unix.sys_read(f.impl.fd, &p[0], len(p))
-	if n < 0 {
-		return -1, _get_platform_error(n)
+	n, errno := linux.read(f.impl.fd, p[:])
+	if errno != .NONE {
+		return -1, _get_platform_error(errno)
+	}
+	return i64(n), n == 0 ? io.Error.EOF : nil
+}
+
+_read_at :: proc(f: ^File, p: []byte, offset: i64) -> (i64, Error) {
+	if offset < 0 {
+		return 0, .Invalid_Offset
+	}
+
+	n, errno := linux.pread(f.impl.fd, p[:], offset)
+	if errno != .NONE {
+		return -1, _get_platform_error(errno)
 	}
 	if n == 0 {
 		return 0, .EOF
@@ -127,91 +171,67 @@ _read :: proc(f: ^File, p: []byte) -> (i64, Error) {
 	return i64(n), nil
 }
 
-_read_at :: proc(f: ^File, p: []byte, offset: i64) -> (n: i64, err: Error) {
-	if offset < 0 {
-		return 0, .Invalid_Offset
-	}
-
-	b, offset := p, offset
-	for len(b) > 0 {
-		m := unix.sys_pread(f.impl.fd, &b[0], len(b), offset)
-		if m < 0 {
-			return -1, _get_platform_error(m)
-		}
-		if m == 0 {
-			return 0, .EOF
-		}
-		n += i64(m)
-		b = b[m:]
-		offset += i64(m)
-	}
-	return
-}
-
 _write :: proc(f: ^File, p: []byte) -> (i64, Error) {
 	if len(p) == 0 {
 		return 0, nil
 	}
-	n := unix.sys_write(f.impl.fd, &p[0], uint(len(p)))
-	if n < 0 {
-		return -1, _get_platform_error(n)
+	n, errno := linux.write(f.impl.fd, p[:])
+	if errno != .NONE {
+		return -1, _get_platform_error(errno)
 	}
 	return i64(n), nil
 }
 
-_write_at :: proc(f: ^File, p: []byte, offset: i64) -> (n: i64, err: Error) {
+_write_at :: proc(f: ^File, p: []byte, offset: i64) -> (i64, Error) {
 	if offset < 0 {
 		return 0, .Invalid_Offset
 	}
 
-	b, offset := p, offset
-	for len(b) > 0 {
-		m := unix.sys_pwrite(f.impl.fd, &b[0], len(b), offset)
-		if m < 0 {
-			return -1, _get_platform_error(m)
-		}
-		n += i64(m)
-		b = b[m:]
-		offset += i64(m)
+	n, errno := linux.pwrite(f.impl.fd, p[:], offset)
+	if errno != .NONE {
+		return -1, _get_platform_error(errno)
 	}
-	return
+	return i64(n), nil
 }
 
 _file_size :: proc(f: ^File) -> (n: i64, err: Error) {
-	s: _Stat = ---
-	res := unix.sys_fstat(f.impl.fd, &s)
-	if res < 0 {
-		return -1, _get_platform_error(res)
+	s: linux.Stat = ---
+	errno := linux.fstat(f.impl.fd, &s)
+	if errno != .NONE {
+		return -1, _get_platform_error(errno)
 	}
-	return s.size, nil
+	return i64(s.size), nil
 }
 
 _sync :: proc(f: ^File) -> Error {
-	return _ok_or_error(unix.sys_fsync(f.impl.fd))
+	return _get_platform_error(linux.fsync(f.impl.fd))
 }
 
 _flush :: proc(f: ^File) -> Error {
-	return _ok_or_error(unix.sys_fsync(f.impl.fd))
+	return _get_platform_error(linux.fsync(f.impl.fd))
 }
 
 _truncate :: proc(f: ^File, size: i64) -> Error {
-	return _ok_or_error(unix.sys_ftruncate(f.impl.fd, size))
+	return _get_platform_error(linux.ftruncate(f.impl.fd, size))
 }
 
 _remove :: proc(name: string) -> Error {
 	TEMP_ALLOCATOR_GUARD()
 	name_cstr := temp_cstring(name) or_return
 
-	fd := unix.sys_open(name_cstr, int(File_Flags.Read))
-	if fd < 0 {
-		return _get_platform_error(fd)
+	fd, errno := linux.open(name_cstr, {.NOFOLLOW})
+	#partial switch (errno) {
+	case .ELOOP: /* symlink */
+	case .NONE:
+		defer linux.close(fd)
+		if _is_dir_fd(fd) {
+			return _get_platform_error(linux.rmdir(name_cstr))
+		}
+	case:
+		return _get_platform_error(errno)
 	}
-	defer unix.sys_close(fd)
 
-	if _is_dir_fd(fd) {
-		return _ok_or_error(unix.sys_rmdir(name_cstr))
-	}
-	return _ok_or_error(unix.sys_unlink(name_cstr))
+	return _get_platform_error(linux.unlink(name_cstr))
 }
 
 _rename :: proc(old_name, new_name: string) -> Error {
@@ -219,7 +239,7 @@ _rename :: proc(old_name, new_name: string) -> Error {
 	old_name_cstr := temp_cstring(old_name) or_return
 	new_name_cstr := temp_cstring(new_name) or_return
 
-	return _ok_or_error(unix.sys_rename(old_name_cstr, new_name_cstr))
+	return _get_platform_error(linux.rename(old_name_cstr, new_name_cstr))
 }
 
 _link :: proc(old_name, new_name: string) -> Error {
@@ -227,148 +247,194 @@ _link :: proc(old_name, new_name: string) -> Error {
 	old_name_cstr := temp_cstring(old_name) or_return
 	new_name_cstr := temp_cstring(new_name) or_return
 
-	return _ok_or_error(unix.sys_link(old_name_cstr, new_name_cstr))
+	return _get_platform_error(linux.link(old_name_cstr, new_name_cstr))
 }
 
 _symlink :: proc(old_name, new_name: string) -> Error {
 	TEMP_ALLOCATOR_GUARD()
 	old_name_cstr := temp_cstring(old_name) or_return
 	new_name_cstr := temp_cstring(new_name) or_return
-
-	return _ok_or_error(unix.sys_symlink(old_name_cstr, new_name_cstr))
+	return _get_platform_error(linux.symlink(old_name_cstr, new_name_cstr))
 }
 
 _read_link_cstr :: proc(name_cstr: cstring, allocator: runtime.Allocator) -> (string, Error) {
 	bufsz : uint = 256
 	buf := make([]byte, bufsz, allocator)
 	for {
-		rc := unix.sys_readlink(name_cstr, &buf[0], bufsz)
-		if rc < 0 {
-			delete(buf)
-			return "", _get_platform_error(rc)
-		} else if rc == int(bufsz) {
+		sz, errno := linux.readlink(name_cstr, buf[:])
+		if errno != .NONE {
+			delete(buf, allocator)
+			return "", _get_platform_error(errno)
+		} else if sz == int(bufsz) {
 			bufsz *= 2
-			delete(buf)
+			delete(buf, allocator)
 			buf = make([]byte, bufsz, allocator)
 		} else {
-			return string(buf[:rc]), nil
+			return string(buf[:sz]), nil
 		}
 	}
 }
 
-_read_link :: proc(name: string, allocator: runtime.Allocator) -> (path: string, err: Error) {
+_read_link :: proc(name: string, allocator: runtime.Allocator) -> (s: string, e: Error) {
 	TEMP_ALLOCATOR_GUARD()
 	name_cstr := temp_cstring(name) or_return
 	return _read_link_cstr(name_cstr, allocator)
 }
 
-_unlink :: proc(name: string) -> Error {
-	TEMP_ALLOCATOR_GUARD()
-	name_cstr := temp_cstring(name) or_return
-	return _ok_or_error(unix.sys_unlink(name_cstr))
-}
-
 _chdir :: proc(name: string) -> Error {
 	TEMP_ALLOCATOR_GUARD()
 	name_cstr := temp_cstring(name) or_return
-	return _ok_or_error(unix.sys_chdir(name_cstr))
+	return _get_platform_error(linux.chdir(name_cstr))
 }
 
 _fchdir :: proc(f: ^File) -> Error {
-	return _ok_or_error(unix.sys_fchdir(f.impl.fd))
+	return _get_platform_error(linux.fchdir(f.impl.fd))
 }
 
 _chmod :: proc(name: string, mode: File_Mode) -> Error {
 	TEMP_ALLOCATOR_GUARD()
 	name_cstr := temp_cstring(name) or_return
-	return _ok_or_error(unix.sys_chmod(name_cstr, uint(mode)))
+	return _get_platform_error(linux.chmod(name_cstr, transmute(linux.Mode)(u32(mode))))
 }
 
 _fchmod :: proc(f: ^File, mode: File_Mode) -> Error {
-	return _ok_or_error(unix.sys_fchmod(f.impl.fd, uint(mode)))
+	return _get_platform_error(linux.fchmod(f.impl.fd, transmute(linux.Mode)(u32(mode))))
 }
 
 // NOTE: will throw error without super user priviledges
 _chown :: proc(name: string, uid, gid: int) -> Error {
 	TEMP_ALLOCATOR_GUARD()
 	name_cstr := temp_cstring(name) or_return
-	return _ok_or_error(unix.sys_chown(name_cstr, uid, gid))
+	return _get_platform_error(linux.chown(name_cstr, linux.Uid(uid), linux.Gid(gid)))
 }
 
 // NOTE: will throw error without super user priviledges
 _lchown :: proc(name: string, uid, gid: int) -> Error {
 	TEMP_ALLOCATOR_GUARD()
 	name_cstr := temp_cstring(name) or_return
-	return _ok_or_error(unix.sys_lchown(name_cstr, uid, gid))
+	return _get_platform_error(linux.lchown(name_cstr, linux.Uid(uid), linux.Gid(gid)))
 }
 
 // NOTE: will throw error without super user priviledges
 _fchown :: proc(f: ^File, uid, gid: int) -> Error {
-	return _ok_or_error(unix.sys_fchown(f.impl.fd, uid, gid))
+	return _get_platform_error(linux.fchown(f.impl.fd, linux.Uid(uid), linux.Gid(gid)))
 }
 
 _chtimes :: proc(name: string, atime, mtime: time.Time) -> Error {
 	TEMP_ALLOCATOR_GUARD()
 	name_cstr := temp_cstring(name) or_return
-	times := [2]Unix_File_Time {
-		{ atime._nsec, 0 },
-		{ mtime._nsec, 0 },
+	times := [2]linux.Time_Spec {
+		{
+			uint(atime._nsec) / uint(time.Second),
+			uint(atime._nsec) % uint(time.Second),
+		},
+		{
+			uint(mtime._nsec) / uint(time.Second),
+			uint(mtime._nsec) % uint(time.Second),
+		},
 	}
-	return _ok_or_error(unix.sys_utimensat(_AT_FDCWD, name_cstr, &times, 0))
+	return _get_platform_error(linux.utimensat(linux.AT_FDCWD, name_cstr, &times[0], nil))
 }
 
 _fchtimes :: proc(f: ^File, atime, mtime: time.Time) -> Error {
-	times := [2]Unix_File_Time {
-		{ atime._nsec, 0 },
-		{ mtime._nsec, 0 },
+	times := [2]linux.Time_Spec {
+		{
+			uint(atime._nsec) / uint(time.Second),
+			uint(atime._nsec) % uint(time.Second),
+		},
+		{
+			uint(mtime._nsec) / uint(time.Second),
+			uint(mtime._nsec) % uint(time.Second),
+		},
 	}
-	return _ok_or_error(unix.sys_utimensat(f.impl.fd, nil, &times, 0))
+	return _get_platform_error(linux.utimensat(f.impl.fd, nil, &times[0], nil))
 }
 
 _exists :: proc(name: string) -> bool {
 	TEMP_ALLOCATOR_GUARD()
 	name_cstr, _ := temp_cstring(name)
-	return unix.sys_access(name_cstr, F_OK) == 0
+	res, errno := linux.access(name_cstr, linux.F_OK)
+	return !res && errno == .NONE
 }
 
 _is_file :: proc(name: string) -> bool {
 	TEMP_ALLOCATOR_GUARD()
 	name_cstr, _ := temp_cstring(name)
-	s: _Stat
-	res := unix.sys_stat(name_cstr, &s)
-	if res < 0 {
+	s: linux.Stat
+	if linux.stat(name_cstr, &s) != .NONE {
 		return false
 	}
-	return S_ISREG(s.mode)
+	return linux.S_ISREG(s.mode)
 }
 
-_is_file_fd :: proc(fd: int) -> bool {
-	s: _Stat
-	res := unix.sys_fstat(fd, &s)
-	if res < 0 { // error
+_is_file_fd :: proc(fd: linux.Fd) -> bool {
+	s: linux.Stat
+	if linux.fstat(fd, &s) != .NONE {
 		return false
 	}
-	return S_ISREG(s.mode)
+	return linux.S_ISREG(s.mode)
 }
 
 _is_dir :: proc(name: string) -> bool {
 	TEMP_ALLOCATOR_GUARD()
 	name_cstr, _ := temp_cstring(name)
-	s: _Stat
-	res := unix.sys_stat(name_cstr, &s)
-	if res < 0 {
+	s: linux.Stat
+	if linux.stat(name_cstr, &s) != .NONE {
 		return false
 	}
-	return S_ISDIR(s.mode)
+	return linux.S_ISDIR(s.mode)
 }
 
-_is_dir_fd :: proc(fd: int) -> bool {
-	s: _Stat
-	res := unix.sys_fstat(fd, &s)
-	if res < 0 { // error
+_is_dir_fd :: proc(fd: linux.Fd) -> bool {
+	s: linux.Stat
+	if linux.fstat(fd, &s) != .NONE {
 		return false
 	}
-	return S_ISDIR(s.mode)
+	return linux.S_ISDIR(s.mode)
+}
+
+/* Certain files in the Linux file system are not actual
+ * files (e.g. everything in /proc/). Therefore, the
+ * read_entire_file procs fail to actually read anything
+ * since these "files" stat to a size of 0.  Here, we just
+ * read until there is nothing left.
+ */
+_read_entire_pseudo_file :: proc { _read_entire_pseudo_file_string, _read_entire_pseudo_file_cstring }
+
+_read_entire_pseudo_file_string :: proc(name: string, allocator: runtime.Allocator) -> (b: []u8, e: Error) {
+	name_cstr := clone_to_cstring(name, allocator) or_return
+	defer delete(name, allocator)
+	return _read_entire_pseudo_file_cstring(name_cstr, allocator)
+}
+
+_read_entire_pseudo_file_cstring :: proc(name: cstring, allocator: runtime.Allocator) -> ([]u8, Error) {
+	fd, errno := linux.open(name, {})
+	if errno != .NONE {
+		return nil, _get_platform_error(errno)
+	}
+	defer linux.close(fd)
+
+	BUF_SIZE_STEP :: 128
+	contents := make([dynamic]u8, 0, BUF_SIZE_STEP, allocator)
+
+	n: int
+	i: int
+	for {
+		resize(&contents, i + BUF_SIZE_STEP)
+		n, errno = linux.read(fd, contents[i:i+BUF_SIZE_STEP])
+		if errno != .NONE {
+			delete(contents)
+			return nil, _get_platform_error(errno)
+		}
+		if n < BUF_SIZE_STEP {
+			break
+		}
+		i += BUF_SIZE_STEP
+	}
+
+	resize(&contents, i + n)
+
+	return contents[:], nil
 }
 
 @(private="package")