zshrs 0.11.1

//! Select/poll builtin module — port of `Src/Modules/zselect.c`.
//!
//! Helper functions                                                         // c:33
//! The builtin itself                                                       // c:61
//!
//! C source has zero `struct ...` / `enum ...` definitions. Rust
//! port matches: zero types. Two fns: `bin_zselect` and the
//! static helper `handle_digits`, plus the 6 module loaders.

use crate::ported::utils::zwarnnam;

/// Port of static helper `handle_digits()` from
/// `Src/Modules/zselect.c:40`. Validates that `argptr` is a
/// digit-prefixed file-descriptor and adds the parsed fd to
/// `fdset`; updates `*fdmax` to `max(*fdmax, fd+1)`. Returns 0 on
/// success, 1 on parse error (after emitting `zwarnnam`).
///
/// C signature: `static int handle_digits(char *nam, char *argptr,
///                                         fd_set *fdset, int *fdmax)`.
/// Rust port matches: takes `&mut libc::fd_set` directly so the
/// FD_SET op runs on the caller's set in place.
pub fn handle_digits(                                                    // c:40
    nam: &str,
    argptr: &str,
    fdset: &mut libc::fd_set,
    fdmax: &mut libc::c_int,
) -> i32 {
    let first = argptr.chars().next();
    if !matches!(first, Some(c) if c.is_ascii_digit()) {                 // c:45 idigit
        zwarnnam(nam, &format!("expecting file descriptor: {}", argptr));
        return 1;                                                        // c:47
    }
    // c:49 — `fd = (int)zstrtol(argptr, &endptr, 10);`
    let (fd_val, endptr) = crate::ported::utils::zstrtol(argptr, 10);
    let fd = fd_val as libc::c_int;
    if !endptr.is_empty() {                                              // c:50 *endptr
        zwarnnam(nam, &format!("garbage after file descriptor: {}", endptr));
        return 1;                                                        // c:52
    }
    unsafe { libc::FD_SET(fd, fdset); }                                  // c:55 FD_SET
    if fd + 1 > *fdmax {                                                 // c:56
        *fdmax = fd + 1;                                                 // c:57
    }
    0                                                                    // c:58
}

/// Port of `bin_zselect(char *nam, char **args, UNUSED(Options ops), UNUSED(int func))` from `Src/Modules/zselect.c:65`. The
/// `zselect` builtin: parses a `[-r|-w|-e] FD ...` argv with an
/// optional `-t TIMEOUT` (hundredths of a second) and an optional
/// `-a NAME` / `-A NAME` for a custom output array / hash, then
/// runs `select(2)` and writes the ready fds back to `$reply`
/// (or the requested array/hash).
///
/// C signature: `static int bin_zselect(char *nam, char **args,
///                                       Options ops, int func)`.
/// Returns 0 on success, 1 on parse/select error or timeout, 2
/// when the host doesn't have `select(2)`.
/// WARNING: param names don't match C — Rust=(nam, args, _func) vs C=(nam, args, ops, func)
pub fn bin_zselect(nam: &str, args: &[String],                               // c:65
                   _ops: &crate::ported::zsh_h::options, _func: i32) -> i32 {
    // C source parses options inline (BUILTIN spec is NULL); the
    // canonical sig still routes the empty `ops`/`func` pair through
    // for shape-parity with the rest of the builtin family.
    let args: Vec<&str> = args.iter().map(String::as_str).collect();
    let args = &args[..];
    // c:67-72 — locals.
    let mut fdset: [libc::fd_set; 3] = unsafe { std::mem::zeroed() };
    for s in &mut fdset {                                                // c:75-76 FD_ZERO
        unsafe { libc::FD_ZERO(s); }
    }
    let fdchar: [u8; 3] = *b"rwe";                                       // c:69
    let mut fdmax: libc::c_int = 0;                                      // c:67
    let mut fdsetind: usize = 0;                                         // c:67
    let mut tv: libc::timeval = libc::timeval { tv_sec: 0, tv_usec: 0 };
    let mut have_timeout = false;                                        // c:70 tvptr=NULL
    let mut outarray: String = "reply".to_string();                      // c:71
    let mut outhash: Option<String> = None;                              // c:72

    // c:78-118 — argv parse.
    let mut i = 0;
    while i < args.len() {                                               // c:78 for(;*args;args++)
        let arg = args[i];
        if let Some(rest) = arg.strip_prefix('-') {                      // c:81
            // Walk each character of the option group.
            let mut chars: Vec<char> = rest.chars().collect();
            let mut j = 0;
            while j < chars.len() {                                      // c:82 for(argptr++; *argptr; argptr++)
                let c = chars[j];
                match c {
                    'a' | 'A' => {                                       // c:88-90
                        // Argument expected — next char or next argv.
                        let arg_str: String = if j + 1 < chars.len() {
                            j += 1;                                      // c:92 argptr++
                            chars[j..].iter().collect()
                        } else if i + 1 < args.len() {
                            i += 1;                                      // c:94
                            args[i].to_string()
                        } else {
                            zwarnnam(nam, &format!("argument expected after -{}", c));
                            return 1;                                    // c:97
                        };
                        // c:99-102 — `idigit(*argptr) || !isident(argptr)` check.
                        if arg_str.is_empty()
                            || arg_str.chars().next().unwrap().is_ascii_digit()
                            || !is_ident(&arg_str)
                        {
                            zwarnnam(nam, &format!("invalid array name: {}", arg_str));
                            return 1;
                        }
                        if c == 'a' {                                    // c:103
                            outarray = arg_str;                          // c:104
                        } else {                                         // c:105
                            outhash = Some(arg_str);                     // c:106
                        }
                        // C: `while (argptr[1]) argptr++;` — break out
                        // of the option-group loop since we've consumed
                        // the rest of `argptr` as the array name.
                        break;
                    }
                    'r' => fdsetind = 0,                                  // c:115
                    'w' => fdsetind = 1,                                  // c:120
                    'e' => fdsetind = 2,                                  // c:125
                    't' => {                                              // c:131
                        // Argument expected.
                        let arg_str: String = if j + 1 < chars.len() {
                            j += 1;
                            chars[j..].iter().collect()
                        } else if i + 1 < args.len() {
                            i += 1;
                            args[i].to_string()
                        } else {
                            zwarnnam(nam, &format!("argument expected after -{}", c));
                            return 1;
                        };
                        let first = arg_str.chars().next();
                        if !matches!(first, Some(d) if d.is_ascii_digit()) {  // c:140
                            zwarnnam(nam, "number expected after -t");
                            return 1;
                        }
                        // c:144 — `tempnum = zstrtol(argptr, &endptr, 10);`
                        let (tempnum, endptr) =
                            crate::ported::utils::zstrtol(&arg_str, 10);
                        if !endptr.is_empty() {                           // c:146 *endptr
                            zwarnnam(nam, &format!("garbage after -t argument: {}", endptr));
                            return 1;                                     // c:149
                        }
                        // c:151-153 — tv populated.
                        have_timeout = true;
                        tv.tv_sec  = (tempnum / 100) as libc::time_t;
                        tv.tv_usec = ((tempnum % 100) * 10000) as libc::suseconds_t;
                        break;                                            // c:156 argptr=endptr-1, then argptr++
                    }
                    _ => {                                                // c:159 default
                        // Digits-following-flag — pass to handle_digits.
                        let argptr_rest: String = chars[j..].iter().collect();
                        if handle_digits(nam, &argptr_rest, &mut fdset[fdsetind], &mut fdmax) != 0 {
                            return 1;                                     // c:162
                        }
                        break;                                             // consumed rest of group
                    }
                }
                j += 1;
            }
        } else if handle_digits(nam, arg, &mut fdset[fdsetind], &mut fdmax) != 0 {  // c:166
            return 1;                                                     // c:167
        }
        i += 1;
    }

    // c:170-175 — select() with EINTR-retry.
    let tvptr: *mut libc::timeval = if have_timeout { &mut tv } else { std::ptr::null_mut() };
    let mut sel: libc::c_int;
    loop {
        sel = unsafe {
            libc::select(
                fdmax,
                &mut fdset[0],
                &mut fdset[1],
                &mut fdset[2],
                tvptr,
            )
        };
        if sel >= 0 { break; }
        let err = std::io::Error::last_os_error();
        if err.raw_os_error() == Some(libc::EINTR) { continue; }          // c:174
        break;
    }

    if sel <= 0 {                                                         // c:177
        if sel < 0 {                                                      // c:178
            zwarnnam(nam, &format!(
                "error on select: {}",
                std::io::Error::last_os_error()
            ));                                                           // c:179
        }
        return 1;                                                         // c:181
    }

    // c:189-243 — build the linked-list of ready fds, then convert
    // to the array/hash output. Rust collapses znewlinklist + walk
    // into Vec<String> and IndexMap<String, String>.
    if let Some(hash_name) = &outhash {                                   // c:191
        // Hash form: keys are fd numbers (as strings), values are
        // (possibly multi-char) "rwe"-subset masks.
        let mut hash: indexmap::IndexMap<String, String> = indexmap::IndexMap::new();
        for ii in 0..3 {                                                  // c:194
            for fd in 0..fdmax {                                          // c:196
                if unsafe { libc::FD_ISSET(fd, &fdset[ii]) } {            // c:197
                    let key = fd.to_string();
                    let mask_char = fdchar[ii] as char;
                    hash.entry(key.clone())
                        .and_modify(|v| {
                            if !v.contains(mask_char) { v.push(mask_char); }
                        })
                        .or_insert_with(|| mask_char.to_string());
                }
            }
        }
        // c:241 — `sethparam(hashname, ...);` — encode as key=val tab-joined.
        let pairs: Vec<String> = hash.into_iter()
            .map(|(k, v)| format!("{}={}", k, v)).collect();
        crate::ported::params::setsparam(hash_name, &pairs.join("\t"));
    } else {
        // Array form: list of fds preceded by `-r`/`-w`/`-e`.
        let mut out: Vec<String> = Vec::new();
        for ii in 0..3 {                                                  // c:194
            let mut emitted_flag = false;                                  // c:213 doneit
            for fd in 0..fdmax {                                          // c:196
                if unsafe { libc::FD_ISSET(fd, &fdset[ii]) } {            // c:197
                    if !emitted_flag {                                    // c:215
                        out.push(format!("-{}", fdchar[ii] as char));     // c:218
                        emitted_flag = true;                              // c:219
                    }
                    out.push(fd.to_string());                             // c:223 zaddlinknode
                }
            }
        }
        // c:243 — `setaparam(outarray, out);` — colon-join through env shim.
        crate::ported::params::setsparam(&outarray, &out.join(":"));
    }

    0                                                                    // c:246
}

/// WARNING: NOT IN ZSELECT.C — Rust char predicate equivalent to C `iident()`
/// (equivalent C logic at Src/Modules/zsh.h:1700).
/// `isident(s)` predicate — identifier validity check matching
/// zsh's `isident()` (Src/utils.c). True iff `s` is non-empty,
/// every char is alnum or `_`, and the first char is not a digit.
fn is_ident(s: &str) -> bool {
    if s.is_empty() { return false; }
    let mut chars = s.chars();
    let first = chars.next().unwrap();
    if first.is_ascii_digit() { return false; }
    if !(first.is_alphanumeric() || first == '_') { return false; }
    chars.all(|c| c.is_alphanumeric() || c == '_')
}

// (impl ShellExecutor block moved to src/fusevm_bridge.rs at the
// "zselect" call site — per the no-shellexecutor-in-src/ported
// rule. Canonical bin_zselect above takes (name, args, ops, func)
// per Src/Modules/zselect.c:65.)

// =====================================================================
// static struct builtin bintab[]                                    c:271
// static struct features module_features                            c:275
// =====================================================================

use crate::ported::zsh_h::module;

// `bintab` — port of `static struct builtin bintab[]` (zselect.c:271).


// `module_features` — port of `static struct features module_features`
// from zselect.c:275.



/// Port of `setup_(UNUSED(Module m))` from `Src/Modules/zselect.c:288`.
#[allow(unused_variables)]
pub fn setup_(m: *const module) -> i32 {                                // c:288
    0                                                                    // c:303
}

/// Port of `features_(UNUSED(Module m), UNUSED(char ***features))` from `Src/Modules/zselect.c:295`.
/// C body: `*features = featuresarray(m, &module_features); return 0;`
pub fn features_(m: *const module, features: &mut Vec<String>) -> i32 { // c:295
    *features = featuresarray(m, module_features());
    0                                                                    // c:310
}

/// Port of `enables_(UNUSED(Module m), UNUSED(int **enables))` from `Src/Modules/zselect.c:303`.
/// C body: `return handlefeatures(m, &module_features, enables);`
pub fn enables_(m: *const module, enables: &mut Option<Vec<i32>>) -> i32 { // c:303
    handlefeatures(m, module_features(), enables) // c:318
}

/// Port of `boot_(UNUSED(Module m))` from `Src/Modules/zselect.c:310`.
#[allow(unused_variables)]
pub fn boot_(m: *const module) -> i32 {                                 // c:310
    0                                                                    // c:325
}

/// Port of `cleanup_(UNUSED(Module m))` from `Src/Modules/zselect.c:318`.
/// C body: `return setfeatureenables(m, &module_features, NULL);`
pub fn cleanup_(m: *const module) -> i32 {                              // c:318
    setfeatureenables(m, module_features(), None) // c:325
}

/// Port of `finish_(UNUSED(Module m))` from `Src/Modules/zselect.c:325`.
#[allow(unused_variables)]
pub fn finish_(m: *const module) -> i32 {                               // c:325
    0                                                                    // c:325
}

#[cfg(test)]
mod tests {
    use super::*;

    fn empty_ops_zs() -> crate::ported::zsh_h::options {
        use crate::ported::zsh_h::{options, MAX_OPS};
        options { ind: [0u8; MAX_OPS], args: Vec::new(),
                  argscount: 0, argsalloc: 0 }
    }
    fn s(args: &[&str]) -> Vec<String> {
        args.iter().map(|a| a.to_string()).collect()
    }

    /// Port of `bin_zselect(char *nam, char **args, UNUSED(Options ops), UNUSED(int func))` from `Src/Modules/zselect.c:65`.
    #[test]
    fn empty_args_with_zero_timeout_returns_one() {
        // C zsh body: with `-t 0` and no fds, select() returns 0
        // immediately and bin_zselect returns 1 (no-fds-ready
        // path). Without `-t`, the call blocks indefinitely (POSIX
        // select(0, _, _, _, NULL) waits forever) — matching C
        // behaviour exactly. Tests therefore always pass `-t 0`.
        let ops = empty_ops_zs();
        let r = bin_zselect("zselect", &s(&["-t", "0"]), &ops, 0);
        assert_eq!(r, 1);
    }

    #[test]
    fn invalid_array_name_returns_one() {
        let ops = empty_ops_zs();
        let r = bin_zselect("zselect", &s(&["-a", "1bad"]), &ops, 0);
        assert_eq!(r, 1);
    }

    #[test]
    fn timeout_garbage_returns_one() {
        let ops = empty_ops_zs();
        let r = bin_zselect("zselect", &s(&["-t", "100x"]), &ops, 0);
        assert_eq!(r, 1);
    }

    #[test]
    fn no_arg_after_a_returns_one() {
        let ops = empty_ops_zs();
        let r = bin_zselect("zselect", &s(&["-a"]), &ops, 0);
        assert_eq!(r, 1);
    }

    /// Port of `bin_zselect(char *nam, char **args, UNUSED(Options ops), UNUSED(int func))` from `Src/Modules/zselect.c:65`.
    #[test]
    fn handle_digits_invalid_input() {
        let mut fdset: libc::fd_set = unsafe { std::mem::zeroed() };
        unsafe { libc::FD_ZERO(&mut fdset); }
        let mut fdmax: libc::c_int = 0;
        assert_eq!(handle_digits("zselect", "abc", &mut fdset, &mut fdmax), 1);
        assert_eq!(handle_digits("zselect", "12abc", &mut fdset, &mut fdmax), 1);
    }

    /// Port of `bin_zselect(char *nam, char **args, UNUSED(Options ops), UNUSED(int func))` from `Src/Modules/zselect.c:65`.
    #[test]
    fn handle_digits_sets_fd_and_fdmax() {
        let mut fdset: libc::fd_set = unsafe { std::mem::zeroed() };
        unsafe { libc::FD_ZERO(&mut fdset); }
        let mut fdmax: libc::c_int = 0;
        assert_eq!(handle_digits("zselect", "5", &mut fdset, &mut fdmax), 0);
        assert_eq!(fdmax, 6);
        assert!(unsafe { libc::FD_ISSET(5, &fdset) });
    }
}

use crate::ported::zsh_h::features as features_t;
use std::sync::{Mutex, OnceLock};

static MODULE_FEATURES: OnceLock<Mutex<features_t>> = OnceLock::new();

// WARNING: NOT IN ZSELECT.C — Rust-only module-framework shim.
// C uses generic featuresarray/handlefeatures/setfeatureenables from
// Src/module.c:3275/3370/3445 with C-side Builtin/Features pointers;
// Rust per-module shims hardcode the bintab/conddefs/mathfuncs/paramdefs.
fn module_features() -> &'static Mutex<features_t> {
    MODULE_FEATURES.get_or_init(|| Mutex::new(features_t {
        bn_list: None,
        bn_size: 1,
        cd_list: None,
        cd_size: 0,
        mf_list: None,
        mf_size: 0,
        pd_list: None,
        pd_size: 0,
        n_abstract: 0,
    }))
}

// Local stubs for the per-module entry points. C uses generic
// `featuresarray`/`handlefeatures`/`setfeatureenables` (module.c:
// 3275/3370/3445) but those take `Builtin` + `Features` pointer
// fields the Rust port doesn't carry. The hardcoded descriptor
// list mirrors the C bintab/conddefs/mathfuncs/paramdefs.
// WARNING: NOT IN ZSELECT.C — Rust-only module-framework shim.
// C uses generic featuresarray/handlefeatures/setfeatureenables from
// Src/module.c:3275/3370/3445 with C-side Builtin/Features pointers;
// Rust per-module shims hardcode the bintab/conddefs/mathfuncs/paramdefs.
fn featuresarray(_m: *const module, _f: &Mutex<features_t>) -> Vec<String> {
    vec!["b:zselect".to_string()]
}

// WARNING: NOT IN ZSELECT.C — Rust-only module-framework shim.
// C uses generic featuresarray/handlefeatures/setfeatureenables from
// Src/module.c:3275/3370/3445 with C-side Builtin/Features pointers;
// Rust per-module shims hardcode the bintab/conddefs/mathfuncs/paramdefs.
fn handlefeatures(
    _m: *const module,
    _f: &Mutex<features_t>,
    enables: &mut Option<Vec<i32>>,
) -> i32 {
    if enables.is_none() {
        *enables = Some(vec![1; 1]);
    }
    0
}

// WARNING: NOT IN ZSELECT.C — Rust-only module-framework shim.
// C uses generic featuresarray/handlefeatures/setfeatureenables from
// Src/module.c:3275/3370/3445 with C-side Builtin/Features pointers;
// Rust per-module shims hardcode the bintab/conddefs/mathfuncs/paramdefs.
fn setfeatureenables(
    _m: *const module,
    _f: &Mutex<features_t>,
    _e: Option<&[i32]>,
) -> i32 {
    0
}