esp-hal/esp-wifi/src/compat/misc.rs
Björn Quentin 54d4407042
Better align atoi to what the C-library does (#2380)
* Better align `atoi` to what the C-library does

* Address review comments

* Clippy

* More clippy

* Prefer `read` over `read_volatile`
2024-10-22 14:55:24 +00:00

242 lines
5.8 KiB
Rust

use crate::compat::malloc::*;
#[no_mangle]
unsafe extern "C" fn fwrite(ptr: *const (), size: usize, count: usize, stream: *const ()) -> usize {
todo!("fwrite {:?} {} {} {:?}", ptr, size, count, stream)
}
#[no_mangle]
unsafe extern "C" fn fopen(filename: *const u8, mode: *const u8) -> *const () {
todo!("fopen {:?} {:?}", filename, mode)
}
#[no_mangle]
unsafe extern "C" fn fgets(str: *const u8, count: u32, file: *const ()) -> *const u8 {
todo!("fgets {:?} {} {:?}", str, count, file)
}
#[no_mangle]
unsafe extern "C" fn fclose(stream: *const ()) -> i32 {
todo!("fclose {:?}", stream);
}
#[no_mangle]
unsafe extern "C" fn strcat(destination: *mut u8, source: *const u8) -> *const u8 {
trace!("strcat {:?} {:?}", destination, source);
let dst: *mut u8 = strchr(destination.cast(), 0) as *mut u8;
let len = strchr(source.cast(), 0) as usize - source as usize;
core::ptr::copy(source, dst, len);
destination
}
#[no_mangle]
unsafe extern "C" fn strcmp(str1: *const i8, str2: *const i8) -> i32 {
trace!("strcmp {:?} {:?}", str1, str2);
let s1 = core::ffi::CStr::from_ptr(str1).to_str().unwrap();
let s2 = core::ffi::CStr::from_ptr(str2).to_str().unwrap();
let x = s1.cmp(s2);
match x {
core::cmp::Ordering::Less => -1,
core::cmp::Ordering::Equal => 0,
core::cmp::Ordering::Greater => 1,
}
}
#[cfg(feature = "have-strchr")]
extern "C" {
fn strchr(str: *const i8, c: i32) -> *const i8;
}
#[cfg(not(feature = "have-strchr"))]
#[no_mangle]
unsafe extern "C" fn strchr(str: *const i8, c: i32) -> *const i8 {
trace!("strchr {:?} {}", str, c);
unsafe {
let mut p = str;
loop {
if *p == c as i8 {
return p;
}
if *p == 0 {
return core::ptr::null();
}
p = p.add(1);
}
}
}
#[no_mangle]
unsafe extern "C" fn strlcpy(dst: *mut u8, src: *const u8, size: usize) -> usize {
trace!("strlcpy {:?} {:?} {}", dst, src, size);
let mut dst = dst;
let mut src = src;
let mut cnt = 0;
loop {
dst.write_volatile(0);
let c = src.read_volatile();
if c == 0 || cnt >= size {
break;
}
dst.write_volatile(c);
dst = dst.add(1);
src = src.add(1);
cnt += 1;
}
cnt
}
#[no_mangle]
unsafe extern "C" fn strstr(str1: *const i8, str2: *const i8) -> *const i8 {
trace!("strstr {:?} {:?}", str1, str2);
let s1 = core::ffi::CStr::from_ptr(str1).to_str().unwrap();
let s2 = core::ffi::CStr::from_ptr(str2).to_str().unwrap();
let idx = s1.find(s2);
match idx {
Some(offset) => str1.add(offset),
None => core::ptr::null(),
}
}
#[no_mangle]
unsafe extern "C" fn strcasecmp(str1: *const u8, str2: *const u8) -> i32 {
trace!("strcasecmp {:?} {:?}", str1, str2);
let mut str1 = str1;
let mut str2 = str2;
let mut c1 = *str1 as char;
let mut c2 = *str2 as char;
while c1 != '\0' && c2 != '\0' {
c1 = c1.to_ascii_lowercase();
c2 = c2.to_ascii_lowercase();
if c1 != c2 {
return c1 as i32 - c2 as i32;
}
str1 = str1.add(1);
str2 = str2.add(1);
c1 = *str1 as char;
c2 = *str2 as char;
}
c1 as i32 - c2 as i32
}
#[no_mangle]
unsafe extern "C" fn strdup(str: *const i8) -> *const u8 {
trace!("strdup {:?}", str);
unsafe {
let s = core::ffi::CStr::from_ptr(str);
let s = s.to_str().unwrap();
let p = malloc(s.len() + 1);
core::ptr::copy_nonoverlapping(str, p as *mut i8, s.len() + 1);
p as *const u8
}
}
#[no_mangle]
unsafe extern "C" fn atoi(str: *const i8) -> i32 {
trace!("atoi {:?}", str);
let mut sign: i32 = 1;
let mut res: i32 = 0;
let mut idx = 0;
// skip leading spaces
while str.add(idx).read() as u8 == b' ' {
idx += 1;
}
// check sign
let c = str.add(idx).read() as u8;
if c == b'-' || c == b'+' {
if c == b'-' {
sign = -1;
}
idx += 1;
}
// parse number digit by digit
loop {
let c = str.add(idx).read() as u8;
if !c.is_ascii_digit() {
break;
}
// if the result would exceed the bounds - return max-value
if res > i32::MAX / 10 || (res == i32::MAX / 10 && c - b'0' > 7) {
return if sign == 1 { i32::MAX } else { i32::MIN };
}
res = 10 * res + (c - b'0') as i32;
idx += 1;
}
res * sign
}
#[derive(Debug, Copy, Clone)]
#[repr(C)]
struct Tm {
tm_sec: u32, // seconds after the minute - [0, 60] including leap second
tm_min: u32, // minutes after the hour - [0, 59]
tm_hour: u32, // hours since midnight - [0, 23]
tm_mday: u32, // day of the month - [1, 31]
tm_mon: u32, // months since January - [0, 11]
tm_year: u32, // years since 1900
tm_wday: u32, // days since Sunday - [0, 6]
tm_yday: u32, // days since January 1 - [0, 365]
tm_isdst: u32, // daylight savings time flag
}
#[no_mangle]
unsafe extern "C" fn mktime(time: *const Tm) -> i64 {
trace!("mktime {:?}", time);
let time = *time;
// Simplified implementation, ignoring time zones, leap seconds, and other
// complexities
let mut days_in_month = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
let is_leap_year = |year: u32| year % 4 == 0 && (year % 100 != 0 || year % 400 == 0);
let mut days = 0;
let year = time.tm_year + 1900;
for y in 1970..year {
days += if is_leap_year(y) { 366 } else { 365 };
}
if is_leap_year(year) {
days_in_month[1] = 29;
}
for m in 0..time.tm_mon {
days += days_in_month[m as usize];
}
days += time.tm_mday - 1;
let seconds = days * 24 * 60 * 60 + time.tm_hour * 60 * 60 + time.tm_min * 60 + time.tm_sec;
seconds as i64
}