Files
Odin/core/os/file_windows.odin
2023-05-06 17:52:08 -07:00

615 lines
14 KiB
Odin

package os
import win32 "core:sys/windows"
import "core:intrinsics"
import "core:runtime"
import "core:unicode/utf16"
is_path_separator :: proc(c: byte) -> bool {
return c == '/' || c == '\\'
}
open :: proc(path: string, mode: int = O_RDONLY, perm: int = 0) -> (Handle, Errno) {
if len(path) == 0 {
return INVALID_HANDLE, ERROR_FILE_NOT_FOUND
}
access: u32
switch mode & (O_RDONLY|O_WRONLY|O_RDWR) {
case O_RDONLY: access = win32.FILE_GENERIC_READ
case O_WRONLY: access = win32.FILE_GENERIC_WRITE
case O_RDWR: access = win32.FILE_GENERIC_READ | win32.FILE_GENERIC_WRITE
}
if mode&O_CREATE != 0 {
access |= win32.FILE_GENERIC_WRITE
}
if mode&O_APPEND != 0 {
access &~= win32.FILE_GENERIC_WRITE
access |= win32.FILE_APPEND_DATA
}
share_mode := win32.FILE_SHARE_READ|win32.FILE_SHARE_WRITE
sa: ^win32.SECURITY_ATTRIBUTES = nil
sa_inherit := win32.SECURITY_ATTRIBUTES{nLength = size_of(win32.SECURITY_ATTRIBUTES), bInheritHandle = true}
if mode&O_CLOEXEC == 0 {
sa = &sa_inherit
}
create_mode: u32
switch {
case mode&(O_CREATE|O_EXCL) == (O_CREATE | O_EXCL):
create_mode = win32.CREATE_NEW
case mode&(O_CREATE|O_TRUNC) == (O_CREATE | O_TRUNC):
create_mode = win32.CREATE_ALWAYS
case mode&O_CREATE == O_CREATE:
create_mode = win32.OPEN_ALWAYS
case mode&O_TRUNC == O_TRUNC:
create_mode = win32.TRUNCATE_EXISTING
case:
create_mode = win32.OPEN_EXISTING
}
wide_path := win32.utf8_to_wstring(path)
handle := Handle(win32.CreateFileW(wide_path, access, share_mode, sa, create_mode, win32.FILE_ATTRIBUTE_NORMAL|win32.FILE_FLAG_BACKUP_SEMANTICS, nil))
if handle != INVALID_HANDLE {
return handle, ERROR_NONE
}
err := Errno(win32.GetLastError())
return INVALID_HANDLE, err
}
close :: proc(fd: Handle) -> Errno {
if !win32.CloseHandle(win32.HANDLE(fd)) {
return Errno(win32.GetLastError())
}
return ERROR_NONE
}
flush :: proc(fd: Handle) -> (err: Errno) {
if !win32.FlushFileBuffers(win32.HANDLE(fd)) {
err = Errno(win32.GetLastError())
}
return
}
write :: proc(fd: Handle, data: []byte) -> (int, Errno) {
if len(data) == 0 {
return 0, ERROR_NONE
}
single_write_length: win32.DWORD
total_write: i64
length := i64(len(data))
for total_write < length {
remaining := length - total_write
to_write := win32.DWORD(min(i32(remaining), MAX_RW))
e := win32.WriteFile(win32.HANDLE(fd), &data[total_write], to_write, &single_write_length, nil)
if single_write_length <= 0 || !e {
err := Errno(win32.GetLastError())
return int(total_write), err
}
total_write += i64(single_write_length)
}
return int(total_write), ERROR_NONE
}
@(private="file")
read_console :: proc(handle: win32.HANDLE, b: []byte) -> (n: int, err: Errno) {
if len(b) == 0 {
return 0, 0
}
BUF_SIZE :: 386
buf16: [BUF_SIZE]u16
buf8: [4*BUF_SIZE]u8
for n < len(b) && err == 0 {
min_read := max(len(b)/4, 1 if len(b) > 0 else 0)
max_read := u32(min(BUF_SIZE, min_read))
if max_read == 0 {
break
}
single_read_length: u32
ok := win32.ReadConsoleW(handle, &buf16[0], max_read, &single_read_length, nil)
if !ok {
err = Errno(win32.GetLastError())
}
buf8_len := utf16.decode_to_utf8(buf8[:], buf16[:single_read_length])
src := buf8[:buf8_len]
ctrl_z := false
for i := 0; i < len(src) && n+i < len(b); i += 1 {
x := src[i]
if x == 0x1a { // ctrl-z
ctrl_z = true
break
}
b[n] = x
n += 1
}
if ctrl_z || single_read_length < max_read {
break
}
// NOTE(bill): if the last two values were a newline, then it is expected that
// this is the end of the input
if n >= 2 && single_read_length == max_read && string(b[n-2:n]) == "\r\n" {
break
}
}
return
}
read :: proc(fd: Handle, data: []byte) -> (int, Errno) {
if len(data) == 0 {
return 0, ERROR_NONE
}
handle := win32.HANDLE(fd)
m: u32
is_console := win32.GetConsoleMode(handle, &m)
single_read_length: win32.DWORD
total_read: int
length := len(data)
// NOTE(Jeroen): `length` can't be casted to win32.DWORD here because it'll overflow if > 4 GiB and return 0 if exactly that.
to_read := min(i64(length), MAX_RW)
e: win32.BOOL
if is_console {
n, err := read_console(handle, data[total_read:][:to_read])
total_read += n
if err != 0 {
return int(total_read), err
}
} else {
// NOTE(Jeroen): So we cast it here *after* we've ensured that `to_read` is at most MAX_RW (1 GiB)
e = win32.ReadFile(handle, &data[total_read], win32.DWORD(to_read), &single_read_length, nil)
}
if single_read_length <= 0 || !e {
err := Errno(win32.GetLastError())
return int(total_read), err
}
total_read += int(single_read_length)
return int(total_read), ERROR_NONE
}
seek :: proc(fd: Handle, offset: i64, whence: int) -> (i64, Errno) {
w: u32
switch whence {
case 0: w = win32.FILE_BEGIN
case 1: w = win32.FILE_CURRENT
case 2: w = win32.FILE_END
}
hi := i32(offset>>32)
lo := i32(offset)
ft := win32.GetFileType(win32.HANDLE(fd))
if ft == win32.FILE_TYPE_PIPE {
return 0, ERROR_FILE_IS_PIPE
}
dw_ptr := win32.SetFilePointer(win32.HANDLE(fd), lo, &hi, w)
if dw_ptr == win32.INVALID_SET_FILE_POINTER {
err := Errno(win32.GetLastError())
return 0, err
}
return i64(hi)<<32 + i64(dw_ptr), ERROR_NONE
}
file_size :: proc(fd: Handle) -> (i64, Errno) {
length: win32.LARGE_INTEGER
err: Errno
if !win32.GetFileSizeEx(win32.HANDLE(fd), &length) {
err = Errno(win32.GetLastError())
}
return i64(length), err
}
@(private)
MAX_RW :: 1<<30
ERROR_EOF :: 38
@(private)
pread :: proc(fd: Handle, data: []byte, offset: i64) -> (int, Errno) {
buf := data
if len(buf) > MAX_RW {
buf = buf[:MAX_RW]
}
o := win32.OVERLAPPED{
OffsetHigh = u32(offset>>32),
Offset = u32(offset),
}
// TODO(bill): Determine the correct behaviour for consoles
h := win32.HANDLE(fd)
done: win32.DWORD
e: Errno
if !win32.ReadFile(h, raw_data(buf), u32(len(buf)), &done, &o) {
e = Errno(win32.GetLastError())
done = 0
}
return int(done), e
}
@(private)
pwrite :: proc(fd: Handle, data: []byte, offset: i64) -> (int, Errno) {
buf := data
if len(buf) > MAX_RW {
buf = buf[:MAX_RW]
}
o := win32.OVERLAPPED{
OffsetHigh = u32(offset>>32),
Offset = u32(offset),
}
h := win32.HANDLE(fd)
done: win32.DWORD
e: Errno
if !win32.WriteFile(h, raw_data(buf), u32(len(buf)), &done, &o) {
e = Errno(win32.GetLastError())
done = 0
}
return int(done), e
}
/*
read_at returns n: 0, err: 0 on EOF
on Windows, read_at changes the position of the file cursor, on *nix, it does not.
bytes: [8]u8{}
read_at(fd, bytes, 0)
read(fd, bytes)
will read from the location twice on *nix, and from two different locations on Windows
*/
read_at :: proc(fd: Handle, data: []byte, offset: i64) -> (n: int, err: Errno) {
if offset < 0 {
return 0, ERROR_NEGATIVE_OFFSET
}
b, offset := data, offset
for len(b) > 0 {
m, e := pread(fd, b, offset)
if e == ERROR_EOF {
err = 0
break
}
if e != 0 {
err = e
break
}
n += m
b = b[m:]
offset += i64(m)
}
return
}
/*
on Windows, write_at changes the position of the file cursor, on *nix, it does not.
bytes: [8]u8{}
write_at(fd, bytes, 0)
write(fd, bytes)
will write to the location twice on *nix, and to two different locations on Windows
*/
write_at :: proc(fd: Handle, data: []byte, offset: i64) -> (n: int, err: Errno) {
if offset < 0 {
return 0, ERROR_NEGATIVE_OFFSET
}
b, offset := data, offset
for len(b) > 0 {
m, e := pwrite(fd, b, offset)
if e != 0 {
err = e
break
}
n += m
b = b[m:]
offset += i64(m)
}
return
}
// NOTE(bill): Uses startup to initialize it
stdin := get_std_handle(uint(win32.STD_INPUT_HANDLE))
stdout := get_std_handle(uint(win32.STD_OUTPUT_HANDLE))
stderr := get_std_handle(uint(win32.STD_ERROR_HANDLE))
get_std_handle :: proc "contextless" (h: uint) -> Handle {
fd := win32.GetStdHandle(win32.DWORD(h))
return Handle(fd)
}
exists :: proc(path: string) -> bool {
runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
wpath := win32.utf8_to_wstring(path, context.temp_allocator)
attribs := win32.GetFileAttributesW(wpath)
return i32(attribs) != win32.INVALID_FILE_ATTRIBUTES
}
is_file :: proc(path: string) -> bool {
runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
wpath := win32.utf8_to_wstring(path, context.temp_allocator)
attribs := win32.GetFileAttributesW(wpath)
if i32(attribs) != win32.INVALID_FILE_ATTRIBUTES {
return attribs & win32.FILE_ATTRIBUTE_DIRECTORY == 0
}
return false
}
is_dir :: proc(path: string) -> bool {
runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
wpath := win32.utf8_to_wstring(path, context.temp_allocator)
attribs := win32.GetFileAttributesW(wpath)
if i32(attribs) != win32.INVALID_FILE_ATTRIBUTES {
return attribs & win32.FILE_ATTRIBUTE_DIRECTORY != 0
}
return false
}
// NOTE(tetra): GetCurrentDirectory is not thread safe with SetCurrentDirectory and GetFullPathName
@private cwd_lock := win32.SRWLOCK{} // zero is initialized
get_current_directory :: proc(allocator := context.allocator) -> string {
win32.AcquireSRWLockExclusive(&cwd_lock)
runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = context.temp_allocator == allocator)
sz_utf16 := win32.GetCurrentDirectoryW(0, nil)
dir_buf_wstr := make([]u16, sz_utf16, context.temp_allocator) // the first time, it _includes_ the NUL.
sz_utf16 = win32.GetCurrentDirectoryW(win32.DWORD(len(dir_buf_wstr)), raw_data(dir_buf_wstr))
assert(int(sz_utf16)+1 == len(dir_buf_wstr)) // the second time, it _excludes_ the NUL.
win32.ReleaseSRWLockExclusive(&cwd_lock)
return win32.utf16_to_utf8(dir_buf_wstr, allocator) or_else ""
}
set_current_directory :: proc(path: string) -> (err: Errno) {
wstr := win32.utf8_to_wstring(path)
win32.AcquireSRWLockExclusive(&cwd_lock)
if !win32.SetCurrentDirectoryW(wstr) {
err = Errno(win32.GetLastError())
}
win32.ReleaseSRWLockExclusive(&cwd_lock)
return
}
change_directory :: proc(path: string) -> (err: Errno) {
runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
wpath := win32.utf8_to_wstring(path, context.temp_allocator)
if !win32.SetCurrentDirectoryW(wpath) {
err = Errno(win32.GetLastError())
}
return
}
make_directory :: proc(path: string, mode: u32 = 0) -> (err: Errno) {
runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
// Mode is unused on Windows, but is needed on *nix
wpath := win32.utf8_to_wstring(path, context.temp_allocator)
if !win32.CreateDirectoryW(wpath, nil) {
err = Errno(win32.GetLastError())
}
return
}
remove_directory :: proc(path: string) -> (err: Errno) {
runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
wpath := win32.utf8_to_wstring(path, context.temp_allocator)
if !win32.RemoveDirectoryW(wpath) {
err = Errno(win32.GetLastError())
}
return
}
@(private)
is_abs :: proc(path: string) -> bool {
if len(path) > 0 && path[0] == '/' {
return true
}
when ODIN_OS == .Windows {
if len(path) > 2 {
switch path[0] {
case 'A'..='Z', 'a'..='z':
return path[1] == ':' && is_path_separator(path[2])
}
}
}
return false
}
@(private)
fix_long_path :: proc(path: string) -> string {
if len(path) < 248 {
return path
}
if len(path) >= 2 && path[:2] == `\\` {
return path
}
if !is_abs(path) {
return path
}
prefix :: `\\?`
path_buf := make([]byte, len(prefix)+len(path)+len(`\`), context.temp_allocator)
copy(path_buf, prefix)
n := len(path)
r, w := 0, len(prefix)
for r < n {
switch {
case is_path_separator(path[r]):
r += 1
case path[r] == '.' && (r+1 == n || is_path_separator(path[r+1])):
r += 1
case r+1 < n && path[r] == '.' && path[r+1] == '.' && (r+2 == n || is_path_separator(path[r+2])):
return path
case:
path_buf[w] = '\\'
w += 1
for ; r < n && !is_path_separator(path[r]); r += 1 {
path_buf[w] = path[r]
w += 1
}
}
}
if w == len(`\\?\c:`) {
path_buf[w] = '\\'
w += 1
}
return string(path_buf[:w])
}
link :: proc(old_name, new_name: string) -> (err: Errno) {
runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
n := win32.utf8_to_wstring(fix_long_path(new_name))
o := win32.utf8_to_wstring(fix_long_path(old_name))
return Errno(win32.CreateHardLinkW(n, o, nil))
}
unlink :: proc(path: string) -> (err: Errno) {
runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
wpath := win32.utf8_to_wstring(path, context.temp_allocator)
if !win32.DeleteFileW(wpath) {
err = Errno(win32.GetLastError())
}
return
}
rename :: proc(old_path, new_path: string) -> (err: Errno) {
runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
from := win32.utf8_to_wstring(old_path, context.temp_allocator)
to := win32.utf8_to_wstring(new_path, context.temp_allocator)
if !win32.MoveFileExW(from, to, win32.MOVEFILE_REPLACE_EXISTING) {
err = Errno(win32.GetLastError())
}
return
}
ftruncate :: proc(fd: Handle, length: i64) -> (err: Errno) {
curr_off, e := seek(fd, 0, 1)
if e != 0 {
return e
}
defer seek(fd, curr_off, 0)
_, e = seek(fd, length, 0)
if e != 0 {
return e
}
ok := win32.SetEndOfFile(win32.HANDLE(fd))
if !ok {
return Errno(win32.GetLastError())
}
return ERROR_NONE
}
truncate :: proc(path: string, length: i64) -> (err: Errno) {
fd: Handle
fd, err = open(path, O_WRONLY|O_CREATE, 0o666)
if err != 0 {
return
}
defer close(fd)
err = ftruncate(fd, length)
return
}
remove :: proc(name: string) -> Errno {
p := win32.utf8_to_wstring(fix_long_path(name))
err, err1: win32.DWORD
if !win32.DeleteFileW(p) {
err = win32.GetLastError()
}
if err == 0 {
return 0
}
if !win32.RemoveDirectoryW(p) {
err1 = win32.GetLastError()
}
if err1 == 0 {
return 0
}
if err != err1 {
a := win32.GetFileAttributesW(p)
if a == ~u32(0) {
err = win32.GetLastError()
} else {
if a & win32.FILE_ATTRIBUTE_DIRECTORY != 0 {
err = err1
} else if a & win32.FILE_ATTRIBUTE_READONLY != 0 {
if win32.SetFileAttributesW(p, a &~ win32.FILE_ATTRIBUTE_READONLY) {
err = 0
if !win32.DeleteFileW(p) {
err = win32.GetLastError()
}
}
}
}
}
return Errno(err)
}
pipe :: proc() -> (r, w: Handle, err: Errno) {
sa: win32.SECURITY_ATTRIBUTES
sa.nLength = size_of(win32.SECURITY_ATTRIBUTES)
sa.bInheritHandle = true
if !win32.CreatePipe((^win32.HANDLE)(&r), (^win32.HANDLE)(&w), &sa, 0) {
err = Errno(win32.GetLastError())
}
return
}