stdio_js.odin workaround

stdio_js.odin

#+private

package odin_libc

import "core:c"

foreign import "odin_env"

@(default_calling_convention = "c")
foreign {
    @(link_name="fopen") _fopen   :: proc (path, mode: cstring) -> FILE ---
    @(link_name="fseek") _fseek   :: proc(file: FILE, offset: c.long, whence: i32) -> i32 ---
    @(link_name="ftell") _ftell   :: proc (stream: FILE) -> c.long ---
    @(link_name="fclose") _fclose :: proc(file: FILE) -> i32 ---
    @(link_name="fread") _fread   :: proc(buffer: [^]byte, size: uint, count: uint, file: FILE) -> uint ---
    @(link_name="fwrite") _fwrite :: proc(buffer: [^]byte, size: uint, count: uint, file: FILE) -> uint  ---
}

_putchar :: proc(char: c.int) -> c.int {
	__write(1, {byte(char)})
	return char
}

_getchar :: proc() -> c.int {
	return EOF
}

@(private="file")
foreign odin_env {
	@(link_name="write")
	__write :: proc "contextless" (fd: u32, p: []byte) ---
}

@(private="file")
__fd :: proc(file: FILE) -> (u32, bool) {
	switch (uint(uintptr(file))) {
	case 2: return 1, true // stdout
	case 3: return 2, true // stderr
	case:   return 0, false
	}
}