feat(core): support building for iOS targets

brush-core/Cargo.toml

@@ -77,6 +77,8 @@ nix = { version = "0.31.2", features = [
     "user",
 ] }
 terminfo = "0.9.0"
+
+[target.'cfg(all(unix, not(target_os = "ios")))'.dependencies]
 uzers = "0.12.2"
 
 [target.wasm32-unknown-unknown.dependencies]

brush-core/src/interp.rs

@@ -138,6 +138,15 @@ impl ExecutionParameters {
         }
     }
 
+    /// Returns whether the given file descriptor was explicitly specified for
+    /// this execution (e.g. via a redirection or pipeline), as opposed to being
+    /// inherited from the shell's persistent open files. Useful for telling a
+    /// redirected/piped stdin from an interactive one.
+    #[must_use]
+    pub fn is_fd_specified(&self, fd: ShellFd) -> bool {
+        matches!(self.open_files.fd_entry(fd), openfiles::OpenFileEntry::Open(_))
+    }
+
     /// Sets the given file descriptor to the provided open file.
     ///
     /// # Arguments

brush-core/src/sys/unix.rs

@@ -11,6 +11,10 @@ pub use crate::sys::tokio_process as process;
 pub mod resource;
 pub mod signal;
 pub mod terminal;
+#[cfg(not(target_os = "ios"))]
+pub(crate) mod users;
+#[cfg(target_os = "ios")]
+#[path = "unix/users_ios.rs"]
 pub(crate) mod users;
 
 /// Platform-specific errors.

brush-core/src/sys/unix/commands.rs

@@ -88,9 +88,9 @@ fn pre_exec_lead_session() -> Result<(), std::io::Error> {
         )));
     }
 
-    #[cfg(not(target_os = "macos"))]
+    #[cfg(not(target_vendor = "apple"))]
     let control = libc::TIOCSCTTY;
-    #[cfg(target_os = "macos")]
+    #[cfg(target_vendor = "apple")]
     let control: u64 = libc::TIOCSCTTY.into();
 
     // SAFETY:

brush-core/src/sys/unix/signal.rs

@@ -92,16 +92,21 @@ pub(crate) fn poll_for_stopped_children() -> Result<bool, error::Error> {
     Ok(found_stopped)
 }
 
-#[cfg(not(any(target_os = "macos", target_os = "netbsd", target_os = "openbsd")))]
+#[cfg(not(any(
+    target_os = "macos",
+    target_os = "netbsd",
+    target_os = "openbsd",
+    target_os = "ios"
+)))]
 fn waitid_all(
     flags: nix::sys::wait::WaitPidFlag,
 ) -> Result<nix::sys::wait::WaitStatus, nix::errno::Errno> {
     nix::sys::wait::waitid(nix::sys::wait::Id::All, flags)
 }
 
-// nix does not expose `waitid` on NetBSD/OpenBSD; `waitpid` for any child is
+// nix does not expose `waitid` on NetBSD/OpenBSD/iOS; `waitpid` for any child is
 // equivalent for the flags used here.
-#[cfg(any(target_os = "netbsd", target_os = "openbsd"))]
+#[cfg(any(target_os = "netbsd", target_os = "openbsd", target_os = "ios"))]
 fn waitid_all(
     flags: nix::sys::wait::WaitPidFlag,
 ) -> Result<nix::sys::wait::WaitStatus, nix::errno::Errno> {

brush-core/src/sys/unix/users_ios.rs

@@ -0,0 +1,70 @@
+//! iOS: no user database is accessible from within the app sandbox; identity
+//! comes from uid/gid syscalls and the process environment.
+
+use crate::error;
+use std::path::PathBuf;
+
+pub(crate) const fn is_root() -> bool {
+    false
+}
+
+pub(crate) fn get_user_home_dir(username: &str) -> Option<PathBuf> {
+    // Only the current (sandboxed) user is resolvable.
+    if get_current_username().is_ok_and(|current| current == username) {
+        get_current_user_home_dir()
+    } else {
+        None
+    }
+}
+
+pub(crate) fn get_current_user_home_dir() -> Option<PathBuf> {
+    std::env::var_os("HOME").map(PathBuf::from)
+}
+
+pub(crate) const fn get_current_user_default_shell() -> Option<PathBuf> {
+    None
+}
+
+#[expect(clippy::unnecessary_wraps)]
+pub(crate) fn get_current_uid() -> Result<u32, error::Error> {
+    // SAFETY: getuid is always successful and has no preconditions.
+    Ok(unsafe { libc::getuid() })
+}
+
+#[expect(clippy::unnecessary_wraps)]
+pub(crate) fn get_current_gid() -> Result<u32, error::Error> {
+    // SAFETY: getgid is always successful and has no preconditions.
+    Ok(unsafe { libc::getgid() })
+}
+
+#[expect(clippy::unnecessary_wraps)]
+pub(crate) fn get_effective_uid() -> Result<u32, error::Error> {
+    // SAFETY: geteuid is always successful and has no preconditions.
+    Ok(unsafe { libc::geteuid() })
+}
+
+#[expect(clippy::unnecessary_wraps)]
+pub(crate) fn get_effective_gid() -> Result<u32, error::Error> {
+    // SAFETY: getegid is always successful and has no preconditions.
+    Ok(unsafe { libc::getegid() })
+}
+
+#[expect(clippy::unnecessary_wraps)]
+pub(crate) fn get_current_username() -> Result<String, error::Error> {
+    Ok(std::env::var("USER").unwrap_or_else(|_| "mobile".to_owned()))
+}
+
+#[expect(clippy::unnecessary_wraps)]
+pub(crate) fn get_user_group_ids() -> Result<Vec<u32>, error::Error> {
+    // SAFETY: getgid is always successful and has no preconditions.
+    Ok(vec![unsafe { libc::getgid() }])
+}
+
+pub(crate) fn get_all_users() -> Result<Vec<String>, error::Error> {
+    Ok(vec![get_current_username()?])
+}
+
+#[expect(clippy::unnecessary_wraps)]
+pub(crate) fn get_all_groups() -> Result<Vec<String>, error::Error> {
+    Ok(vec!["mobile".to_owned()])
+}