os: change f.write and f.writeln to return options too

pull/6355/head
Delyan Angelov 2020-09-12 08:31:15 +03:00
parent 332f3a924c
commit 60ecb7e4b6
2 changed files with 24 additions and 13 deletions

View File

@ -925,7 +925,7 @@ A defer statement defers the execution of a block of statements until the surrou
```v
fn read_log() {
f := os.open('log.txt')
f := os.open('log.txt') or { panic(err) }
defer { f.close() }
...
if !ok {

View File

@ -3,9 +3,9 @@ module os
import strings
pub struct File {
cfile voidptr // Using void* instead of FILE*
cfile voidptr // Using void* instead of FILE*
pub:
fd int
fd int
pub mut:
is_opened bool
}
@ -22,9 +22,9 @@ pub fn (f File) is_opened() bool {
}
// **************************** Write ops ***************************
pub fn (mut f File) write(s string) {
pub fn (mut f File) write(s string) ?int {
if !f.is_opened {
return
return error('file is not opened')
}
/*
$if linux {
@ -34,12 +34,16 @@ pub fn (mut f File) write(s string) {
}
}
*/
C.fwrite(s.str, s.len, 1, f.cfile)
written := C.fwrite(s.str, s.len, 1, f.cfile)
if written == 0 && s.len != 0 {
return error('0 bytes written')
}
return written
}
pub fn (mut f File) writeln(s string) {
pub fn (mut f File) writeln(s string) ?int {
if !f.is_opened {
return
return error('file is not opened')
}
/*
$if linux {
@ -51,8 +55,15 @@ pub fn (mut f File) writeln(s string) {
}
*/
// TODO perf
C.fwrite(s.str, s.len, 1, f.cfile)
C.fputs('\n', f.cfile)
written := C.fwrite(s.str, s.len, 1, f.cfile)
if written == 0 && s.len != 0 {
return error('0 bytes written')
}
x := C.fputs('\n', f.cfile)
if x < 0 {
return error('could not add newline')
}
return (written + 1)
}
pub fn (mut f File) write_bytes(data voidptr, size int) int {
@ -74,8 +85,8 @@ pub fn (f &File) read_bytes(size int) []byte {
// read_bytes_at reads an amount of bytes at the given position in the file
pub fn (f &File) read_bytes_at(size, pos int) []byte {
//mut arr := [`0`].repeat(size)
mut arr := []byte{ len:size }
// mut arr := [`0`].repeat(size)
mut arr := []byte{len: size}
C.fseek(f.cfile, pos, C.SEEK_SET)
nreadbytes := C.fread(arr.data, 1, size, f.cfile)
C.fseek(f.cfile, 0, C.SEEK_SET)
@ -143,7 +154,7 @@ pub fn (mut f File) get_line() ?string {
mut blen := vstrlen(bufbp)
res.write_bytes(bufbp, blen)
unsafe {
if blen == 0 || bufbp[blen-1] == `\n` || bufbp[blen-1] == `\r` {
if blen == 0 || bufbp[blen - 1] == `\n` || bufbp[blen - 1] == `\r` {
break
}
}