Build fails on Android/Termux

[LHLaurini]

Build fails on Termux with:

~/http $ cargo build
warning: file `/data/data/com.termux/files/home/http/src/main.rs` found to be present in multiple build targets:
  * `bin` target `http`
  * `bin` target `httplz`
   Compiling https v1.13.2 (/data/data/com.termux/files/home/http)
error[E0308]: mismatched types
    --> src/util/os/non_windows_non_macos.rs:39:47
     |
39   |             let ok = unsafe { ioctl(dev_file, BLKGETSIZE, &mut block_count as *mut c_ulong) } == 0;
     |                               -----           ^^^^^^^^^^ expected `i32`, found `u64`
     |                               |
     |                               arguments to this function are incorrect
     |
note: function defined here
    --> /data/data/com.termux/files/home/.cargo/registry/src/index.crates.io-6f17d22bba15001f/libc-0.2.147/src/unix/linux_like/android/mod.rs:3172:12
     |
3172 |     pub fn ioctl(fd: ::c_int, request: ::c_int, ...) -> ::c_int;
     |            ^^^^^
help: you can convert a `u64` to an `i32` and panic if the converted value doesn't fit
     |
39   |             let ok = unsafe { ioctl(dev_file, BLKGETSIZE.try_into().unwrap(), &mut block_count as *mut c_ulong) } == 0;
     |                                                         ++++++++++++++++++++

For more information about this error, try `rustc --explain E0308`.
error: could not compile `https` (bin "httplz") due to previous error
warning: build failed, waiting for other jobs to finish...
error: could not compile `https` (bin "http") due to previous error
~/http $

It seems the signature is different for Linux and Android. While Linux uses ::c_ulong (u64), Android uses ::c_int (i32).

The suggested fix works. I'll gladly propose a pull request if that is valid.

[nabijaczleweli]

Hm, apparently

musl$ git grep ioctl\(int
include/stropts.h:int ioctl(int, int, ...);
src/misc/ioctl.c:int ioctl(int fd, int req, ...)

but

glibc$ git grep ioctl\ \(int
hurd/hurdioctl.c:fioctl (int fd,
include/sys/ioctl.h:extern int __ioctl (int __fd, unsigned long int __request, ...);
manual/llio.texi:@deftypefun int ioctl (int @var{filedes}, int @var{command}, @dots{})
misc/ioctl.c:__ioctl (int fd, unsigned long int request, ...)
misc/sys/ioctl.h:extern int ioctl (int __fd, unsigned long int __request, ...) __THROW;
sysdeps/mach/hurd/ioctl.c:__ioctl (int fd, unsigned long int request, ...)
sysdeps/unix/sysv/linux/ioctl.c:__ioctl (int fd, unsigned long int request, ...)

baffling!

I think android uses bionic which is a fork of musl as libc, so this would be congruent.

[nabijaczleweli]

https://lore.kernel.org/linux-man/israsi2qmpudilwpy2h6vj4dda7jofrc3oolhrcs4cpwvwzl5x@ur3oua7jxgs3/t/#u :v

[nabijaczleweli]

Wait, we even handle this:

    let ioctl_request_type = match &env::var("CARGO_CFG_TARGET_ENV").expect("CARGO_CFG_TARGET_ENV")[..] {
        "musl" => "libc::c_int",
        _ => "libc::c_ulong",
    };

of course, since we handle it like this instead of by autodetecting, it's bound to break when someone builds on illumos or any other non-BSD host. Cool.

[nabijaczleweli]

Can you try the current devel branch (at least 9e6fcd11691d01fa2e304b7a7d0fe23b859306a1)?

[LHLaurini]

Can you try the current devel branch (at least 9e6fcd1)?

Sure. That fixes the error. Now it builds correctly.

[nabijaczleweli]

Released in v2.0.0.