forjar 1.29.0

Rust-native Infrastructure as Code — bare-metal first, BLAKE3 state, provenance tracing
Documentation
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//! FJ-51: the cargo package provider — cached `cargo install` plus the
//! `.crates.toml` registration that tells cargo what forjar installed.
//!
//! Split out of package.rs to keep every file under the 500-line limit.

use crate::core::shell_escape::sh_squote;
use crate::core::types::Resource;

use super::{parse_cargo_features, per_package_query, per_package_script};

/// FJ-51: Cargo binary cache — skip recompilation when cached binary exists.
///
/// Cache layout: `$FORJAR_CACHE_DIR/<pkg>-<version>-<arch>/bin/`
/// Default cache dir: `~/.forjar/cache/cargo`
/// Disable: `FORJAR_NO_CARGO_CACHE=1`
///
/// Supports `crate[feat1,feat2]` syntax in package names to pass `--features`
/// to `cargo install`. Example: `packages: ["whisper-apr[cli]"]`.
/// True if a cargo crate name / feature uses only the cargo-legal charset
/// (`[A-Za-z0-9._-]`). Used to reject names that would otherwise be
/// interpolated into the double-quoted cache key, where `$(...)`/backticks
/// would otherwise be live.
fn is_safe_cargo_token(tok: &str) -> bool {
    !tok.is_empty()
        && tok
            .chars()
            .all(|c| c.is_ascii_alphanumeric() || matches!(c, '.' | '_' | '-'))
}

/// True if `version` is a safe cargo version requirement charset.
fn is_safe_cargo_version(ver: &str) -> bool {
    !ver.is_empty()
        && ver.chars().all(|c| {
            c.is_ascii_alphanumeric() || matches!(c, '.' | '_' | '-' | '+' | '*' | '~' | '^')
        })
}

/// Validate every cargo package spec (crate name + features) and the optional
/// version against the cargo-legal charset. Returns the offending token on
/// the first failure.
fn first_unsafe_cargo_token<'a>(
    packages: &'a [String],
    version: Option<&'a str>,
) -> Option<&'a str> {
    if let Some(v) = version {
        if !is_safe_cargo_version(v) {
            return Some(v);
        }
    }
    for p in packages {
        let (crate_name, features) = parse_cargo_features(p);
        if !is_safe_cargo_token(crate_name) {
            return Some(crate_name);
        }
        if let Some(bad) = features.into_iter().find(|f| !is_safe_cargo_token(f)) {
            return Some(bad);
        }
    }
    None
}

/// The PATH repair that EVERY cargo-provider script emits before it looks for
/// `cargo` or for a crate's binary.
///
/// # Why this exists (forjar#489)
///
/// The install action bootstraps rustup with `--no-modify-path` and then
/// repairs its own `PATH`. The CHECK and the DRIFT observable did not, so on a
/// host where cargo is absent from the NON-INTERACTIVE PATH, forjar installed a
/// crate successfully and then reported it `missing:` forever.
///
/// forjar CREATES that host itself. `rustup-init -y --no-modify-path` appends
/// `. "$HOME/.cargo/env"` to the BOTTOM of `~/.bashrc` (line 118 on the box
/// this was measured on), and Ubuntu's stock `~/.bashrc` returns at line 8 when
/// the shell is not interactive — which is what `ssh host 'cmd'` gives you. So
/// the sourcing line never runs, and the PATH forjar's own check inherits has
/// no cargo in it.
///
/// Measured on `yoga` against 1.25.2, freshly reimaged: `~/.cargo/bin/rg`
/// present and executable, `rg --version` -> `ripgrep 15.1.0`,
/// `~/.cargo/.crates.toml` valid and listing it, `cargo install --list` listing
/// it — and `forjar check` printing `missing:ripgrep`. Same for `bat` and
/// `fd-find`. The second symptom is the same root cause seen from the apply
/// side: the install action's `command -v cargo ||` guard kept missing, so
/// every apply re-ran the rustup installer over a toolchain already there.
///
/// # Why one helper rather than three copies
///
/// The three sites disagreeing is the defect. A shared emitter means a future
/// edit cannot fix the check and forget the observable.
///
/// # Shape
///
/// - Honours `CARGO_HOME` exactly as `_CARGO_BIN`/`_CRATES_TOML` below do; the
///   fleet runs a shared `CARGO_HOME` on several boxes.
/// - IDEMPOTENT: the `case` guard means re-running it (or an apply that also
///   repairs PATH inside its rustup block) cannot grow `$PATH` without bound.
/// - Safe under `set -u`: `${PATH:-}` rather than `$PATH`, since the check
///   scripts run with `set -euo pipefail` in force.
/// - It modifies THIS script's environment only. It writes no shell rc file
///   and does not pass `--modify-path` to rustup: forjar does not own the
///   operator's login shell.
pub(crate) fn path_prelude() -> &'static str {
    "# forjar#489: cargo may be installed and absent from the NON-INTERACTIVE\n\
     # PATH -- rustup is bootstrapped with --no-modify-path and Ubuntu's\n\
     # ~/.bashrc returns before the line rustup appends. Repair PATH here, in\n\
     # this script's own environment, or the check reports `missing:` for a\n\
     # crate it just installed. Idempotent, and honours CARGO_HOME.\n\
     case \":${PATH:-}:\" in\n\
       *\":${CARGO_HOME:-$HOME/.cargo}/bin:\"*) ;;\n\
       *) export PATH=\"${CARGO_HOME:-$HOME/.cargo}/bin:${PATH:-}\" ;;\n\
     esac"
}

pub(crate) fn apply_cargo_present(resource: &Resource) -> String {
    let packages = &resource.packages;
    let version = resource.version.as_deref();
    let source = resource.source.as_deref();

    // FJ-154: reject crate/feature/version tokens that aren't cargo-legal,
    // since they flow into a double-quoted cache key where command
    // substitution would otherwise be live. Path installs (source set) skip
    // the cache, so they only need the install arg escaped (done below).
    if source.is_none() {
        if let Some(bad) = first_unsafe_cargo_token(packages, version) {
            return format!(
                "echo {} >&2; exit 1",
                sh_squote(&format!("ERROR: unsafe cargo package/version token: {bad}"))
            );
        }
    }

    let installs: Vec<String> = packages
        .iter()
        .map(|p| match (source, version) {
            // Local path installs — no caching, always rebuild
            (Some(s), _) => {
                let (_, features) = parse_cargo_features(p);
                let features_arg = if features.is_empty() {
                    String::new()
                } else {
                    format!(" --features {}", sh_squote(&features.join(",")))
                };
                format!(
                    "cargo install --force --locked --path {}{features_arg}",
                    sh_squote(s)
                )
            }
            (None, ver) => cargo_cached_install(p, ver),
        })
        .collect();
    // Limit build parallelism to avoid OOM on high-core-count machines.
    // Respects CARGO_BUILD_JOBS if already set; defaults to min(nproc/2, 8).
    format!(
        "set -euo pipefail\n\
         {path_prelude}\n\
         command -v cargo >/dev/null 2>&1 || {{\n\
           RUSTUP_INIT=$(mktemp /tmp/rustup-init.XXXXXX)\n\
           curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs -o \"$RUSTUP_INIT\"\n\
           chmod +x \"$RUSTUP_INIT\"\n\
           \"$RUSTUP_INIT\" -y --no-modify-path\n\
           rm -f \"$RUSTUP_INIT\"\n\
           export PATH=\"${{CARGO_HOME:-$HOME/.cargo}}/bin:$PATH\"\n\
         }}\n\
         if [ -z \"${{CARGO_BUILD_JOBS:-}}\" ]; then\n\
           _nproc=$(nproc 2>/dev/null || echo 4)\n\
           _half=$(( _nproc / 2 ))\n\
           [ \"$_half\" -lt 1 ] && _half=1\n\
           [ \"$_half\" -gt 8 ] && _half=8\n\
           export CARGO_BUILD_JOBS=$_half\n\
         fi\n\
         _CARGO_BIN=\"${{CARGO_HOME:-$HOME/.cargo}}/bin\"\n\
         _CRATES_TOML=\"${{CARGO_HOME:-$HOME/.cargo}}/.crates.toml\"\n\
         {install_fns}\n\
         # TELL CARGO WHAT WE INSTALLED (forjar#320).\n\
         #\n\
         # `cargo install --root $_STAGING` writes its registry entry to\n\
         # $_STAGING/.crates.toml. We copy only bin/* out and then delete the\n\
         # staging dir, so $CARGO_HOME/.crates.toml never learns about the\n\
         # binaries we just put in $CARGO_HOME/bin. `cargo install --list` then\n\
         # reports the crate MISSING forever, and package_check.rs reads exactly\n\
         # that -- so forjar failed its own check for work it had done.\n\
         #\n\
         # Measured on gx10: rg/fd/bat/hyperfine installed and working, cargo\n\
         # naming none of them; the same registry claiming forjar 1.16.0 on a\n\
         # box running 1.18.0. Wrong in BOTH directions.\n\
         #\n\
         # APPEND-ONLY AND KEYED. `.crates.toml` is `[v1]` followed by one line\n\
         # per install, keyed `\"name ver (source)\" = [\"bin\", ...]`. We drop any\n\
         # existing line for this crate name and append the new one, so a\n\
         # reinstall updates rather than duplicating.\n\
         #\n\
         # Deliberately NOT a TOML parser: this is generated POSIX shell running\n\
         # on hosts that may lack python, and a half-written .crates.toml breaks\n\
         # `cargo install` for every crate on the machine. Write to a temp file\n\
         # and `mv` -- atomic within a filesystem -- so an interrupted run leaves\n\
         # the original intact.\n\
         #\n\
         # ASK CARGO WHETHER THE BYTES ARE READABLE, BEFORE COMMITTING THEM.\n\
         #\n\
         # forjar#345: the merge below is entry-aware now, but \"we wrote it\" is\n\
         # not \"cargo can read it\". The destination on a real host may ALREADY\n\
         # be wreckage left by an older forjar, and a correct merge INTO invalid\n\
         # TOML is still invalid TOML. cargo rejects the WHOLE file for one bad\n\
         # entry, so committing a bad merge costs every crate on the machine:\n\
         # `cargo install --list` names none of them while every binary still\n\
         # runs, and package_check reports `missing:<crate>` forever.\n\
         #\n\
         # Ask CARGO, not a TOML library. cargo is the only consumer that\n\
         # matters and it is the parser that rejected the file on intel. The\n\
         # throwaway CARGO_HOME means the probe cannot touch the real one.\n\
         #\n\
         # Fail-OPEN on absent cargo, failed mktemp or failed cp: a broken /tmp\n\
         # must not wedge every install on the box. Costs 0.015s per crate.\n\
         _fj_crates_ok() {{\n\
           command -v cargo >/dev/null 2>&1 || return 0\n\
           _vh=$(mktemp -d /tmp/forjar-crates.XXXXXX) || return 0\n\
           if ! cp \"$1\" \"$_vh/.crates.toml\" 2>/dev/null; then\n\
             if [ -n \"$_vh\" ]; then rm -rf \"$_vh\"; fi\n\
             return 0\n\
           fi\n\
           if CARGO_HOME=\"$_vh\" cargo install --list >/dev/null 2>\"$_vh/err\"; then\n\
             if [ -n \"$_vh\" ]; then rm -rf \"$_vh\"; fi\n\
             return 0\n\
           fi\n\
           sed 's/^/forjar: cargo: /' \"$_vh/err\" >&2\n\
           if [ -n \"$_vh\" ]; then rm -rf \"$_vh\"; fi\n\
           return 1\n\
         }}\n\
         _fj_register() {{\n\
           _src=\"$1\"\n\
           [ -f \"$_src\" ] || return 0\n\
           _key=$(grep -v '^\\[v1\\]' \"$_src\" | grep -v '^[[:space:]]*$' | head -1 | sed 's/^\"\\([^ ]*\\) .*/\\1/')\n\
           [ -n \"$_key\" ] || return 0\n\
           _tmp=$(mktemp \"${{_CRATES_TOML}}.forjar.XXXXXX\") || return 0\n\
           echo '[v1]' > \"$_tmp\"\n\
           if [ -f \"$_CRATES_TOML\" ]; then\n\
             awk -v k=\"$_key\" 'index($0, \"\\\"\" k \" \") == 1 {{ if ($0 ~ /=[[:space:]]*\\[$/) skip=1; next }} skip {{ if ($0 ~ /^[[:space:]]*\\]/) skip=0; next }} /^\\[v1\\]$/ {{ next }} {{ print }}' \"$_CRATES_TOML\" >> \"$_tmp\" || true\n\
           fi\n\
           awk -v k=\"$_key\" 'index($0, \"\\\"\" k \" \") == 1 {{ print; if ($0 ~ /=[[:space:]]*\\[$/) inarr=1; next }} inarr {{ print; if ($0 ~ /^[[:space:]]*\\]/) inarr=0 }}' \"$_src\" >> \"$_tmp\"\n\
           # READ IT BACK BEFORE COMMITTING IT (forjar#345). `mv` cannot fail\n\
           # on content, so an unconditional commit here reported CONVERGED for\n\
           # a registry cargo could no longer parse. Refuse instead, loudly, and\n\
           # leave the destination byte-identical -- `return 1` under\n\
           # `set -euo pipefail` fails the resource rather than lying about it.\n\
           if ! _fj_crates_ok \"$_tmp\"; then\n\
             rm -f \"$_tmp\"\n\
             if [ -f \"$_CRATES_TOML\" ] && ! _fj_crates_ok \"$_CRATES_TOML\" 2>/dev/null; then\n\
               echo \"ERROR: $_CRATES_TOML is ALREADY unparseable; refusing to merge $_key into it\" >&2\n\
               echo \"HINT: rebuild it from .crates2.json, or move it aside and re-run\" >&2\n\
             else\n\
               echo \"ERROR: merging $_key would make $_CRATES_TOML unparseable; nothing written\" >&2\n\
             fi\n\
             return 1\n\
           fi\n\
           mv -f \"$_tmp\" \"$_CRATES_TOML\"\n\
         }}\n\
         {}",
        installs.join("\n"),
        path_prelude = path_prelude(),
        install_fns = crate::core::shell_install::atomic_install_dir_fn()
    )
}

/// Generate a cached cargo install script for a single crate.
///
/// On cache hit: copy pre-built binaries from cache, skip compilation entirely.
/// On cache miss: `cargo install --root <staging>`, then populate cache + install.
///
/// Supports `crate[feat1,feat2]` syntax — features are passed via `--features`
/// and included in the cache key to avoid feature-set collisions.
///
/// Detects empty staging bin dir (no binaries produced) and emits a clear error
/// with a hint about `--features`, instead of failing on `cp` with a cryptic message.
///
/// Places the binaries with `_fj_install_bins` — stage a sibling, `rename(2)`.
/// Not `cp`, and no longer `install(1)`.
///
/// `cp` REFUSES to overwrite a dangling symlink — "cp: not writing through
/// dangling symlink" — and that is precisely the wreckage this resource has to
/// repair: a CI cache-prune step deletes the real files in a shared
/// `~/.cargo/bin` and leaves the symlinks behind, pointing at nothing.
/// Measured on paiml/infra's intel 2026-08-19: with `pzsh` reduced to a
/// dangling symlink, `forjar apply --refresh` correctly DETECTED the divergence
/// and then died on `cp`, so it could see the damage and not fix it. `cp -f`
/// does not help — coreutils refuses that too (verified on the host).
///
/// `install(1)` cleared that, and ETXTBSY with it, which is why this line read
/// `install -m 755` until now. What it did NOT clear is the gap: GNU `install`
/// unlinks the destination and then creates it, so the path is briefly ABSENT.
/// On the host this matters for — sixteen CI runners sharing one
/// `$CARGO_HOME/bin` — an `exec` landing in that window fails ENOENT. Measured
/// on lambda-labs, statting the destination while it was replaced 4000 times:
/// `install(1)` 10611 absent of 396132; temp + `mv` 0 of 741725.
///
/// `rename(2)` has no such window and is not GNU-only, so it also works on the
/// fleet's macOS box. See `core::shell_install` for the full reasoning.
fn cargo_cached_install(pkg: &str, version: Option<&str>) -> String {
    let (crate_name, features) = parse_cargo_features(pkg);
    let ver_tag = version.unwrap_or("latest");
    let install_arg = match version {
        Some(v) => sh_squote(&format!("{crate_name}@{v}")),
        None => sh_squote(crate_name),
    };
    let features_arg = if features.is_empty() {
        String::new()
    } else {
        format!(" --features {}", sh_squote(&features.join(",")))
    };
    let cache_suffix = if features.is_empty() {
        String::new()
    } else {
        format!("+{}", features.join(","))
    };
    format!(
        "_CACHE_KEY=\"{crate_name}-{ver_tag}{cache_suffix}-$(uname -m)\"\n\
         _CACHE_DIR=\"${{FORJAR_CACHE_DIR:-$HOME/.forjar/cache/cargo}}/$_CACHE_KEY\"\n\
         if [ -z \"${{FORJAR_NO_CARGO_CACHE:-}}\" ] && \
            [ -d \"$_CACHE_DIR/bin\" ] && \
            ls \"$_CACHE_DIR/bin/\"* >/dev/null 2>&1 && \\\n\
            [ -f \"$_CACHE_DIR/.crates.toml\" ]; then\n\
           _fj_install_bins \"$_CACHE_DIR/bin\" \"$_CARGO_BIN\"\n\
           _fj_register \"$_CACHE_DIR/.crates.toml\"\n\
           echo \"forjar: cache-hit {crate_name} [$_CACHE_KEY]\"\n\
         else\n\
           _STAGING=$(mktemp -d /tmp/forjar-cargo.XXXXXX)\n\
           cargo install --force --locked --root \"$_STAGING\"{features_arg} {install_arg}\n\
           if [ ! -d \"$_STAGING/bin\" ] || ! ls \"$_STAGING/bin/\"* >/dev/null 2>&1; then\n\
             echo \"ERROR: cargo install {crate_name} produced no binaries\" >&2\n\
             echo \"HINT: does the crate need --features? Use packages: [\\\"{crate_name}[feature_name]\\\"]\" >&2\n\
             rm -rf \"$_STAGING\"\n\
             exit 1\n\
           fi\n\
           if [ -z \"${{FORJAR_NO_CARGO_CACHE:-}}\" ]; then\n\
             mkdir -p \"$_CACHE_DIR\"\n\
             cp -a \"$_STAGING/bin\" \"$_CACHE_DIR/\"\n\
             cp -f \"$_STAGING/.crates.toml\" \"$_CACHE_DIR/.crates.toml\" 2>/dev/null || true\n\
           fi\n\
           _fj_install_bins \"$_STAGING/bin\" \"$_CARGO_BIN\"\n\
           _fj_register \"$_STAGING/.crates.toml\"\n\
           rm -rf \"$_STAGING\"\n\
           echo \"forjar: cached {crate_name} [$_CACHE_KEY]\"\n\
         fi"
    )
}

/// Remove cargo-installed crates.
///
/// forjar#278: this arm did not exist, so `(cargo, absent)` fell to the
/// catch-all, echoed, and reported converged — a declared removal that never
/// removed anything.
///
/// `|| true` matches the apt/uv/brew absent arms: uninstalling a crate that is
/// not installed is the desired end state, not a failure. The check script is
/// what decides convergence, and it asks whether the crate is gone.
pub(crate) fn apply_cargo_absent(resource: &Resource) -> String {
    per_package_script(&resource.packages, |p| {
        let (crate_name, _) = parse_cargo_features(p);
        format!(
            "cargo uninstall {} 2>/dev/null || true",
            sh_squote(crate_name)
        )
    })
}

/// Query cargo's own registry for what is installed (for state hashing).
///
/// Feeds DRIFT, so its blindness is the expensive half — see the body.
pub(crate) fn state_query(packages: &[String]) -> String {
    // GH-257: ask cargo, not the PATH — see package_check.rs for the
    // full reasoning. This one feeds DRIFT, so its blindness is the
    // more expensive half: with `command -v <crate_name>`, a crate
    // whose binary is named differently (kani-verifier -> cargo-kani)
    // reads as MISSING forever, and a dangling symlink reads as
    // installed. Neither state produces a useful drift signal, which is
    // why an intel host lost rustup, cargo and forjar without a single
    // drift finding.
    // ...AND CHECK THE BINARIES, NOT ONLY THE REGISTRATION.
    //
    // `cargo install --list` reads $CARGO_HOME/.crates.toml — METADATA.
    // It does not stat anything. So when $CARGO_HOME/bin is pruned (which
    // on this fleet is routine: Swatinem/rust-cache's POST step does it,
    // and 16 runners share one $HOME) every binary dies, .crates.toml
    // survives, and this observable keeps reporting `installed`.
    //
    // Measured 2026-08-24 on intel: `cargo-kani` and `kani` both absent
    // from PATH, `~/.kani` intact, and `forjar drift` across the whole
    // machine reported "No drift detected" eight times. The comment this
    // replaces already named the symptom — "why an intel host lost
    // rustup, cargo and forjar without a single drift finding" — and
    // then picked an observable that cannot see it either.
    //
    // Registration alone is not installation. `command -v <crate>` alone
    // is worse (kani-verifier installs `cargo-kani`, not `kani-verifier`,
    // and a dangling symlink reads as present). So do BOTH: take the
    // binary names cargo itself lists under the crate, and require each
    // to exist and be executable.
    //
    // `cargo install --list` prints:
    //     kani-verifier v0.67.0:
    //         cargo-kani
    //         kani
    // Top-level lines are unindented; binaries are indented beneath.
    // Order is stable, so the digest is stable. (paiml/infra#208.)
    let queries = per_package_query(packages, |p| {
        let (crate_name, _) = parse_cargo_features(p);
        let awk = format!(
            "awk -v c={} '/^[^[:space:]]/{{inblk=($1==c)}} inblk&&/^[[:space:]]/{{print $1}}'",
            sh_squote(crate_name)
        );
        format!(
            "if cargo install --list 2>/dev/null | grep -q {reg}; then\n                           bins=$(cargo install --list 2>/dev/null | {awk})\n                           if [ -z \"$bins\" ]; then echo {noBins}\n                           else\n                             st=''\n                             for b in $bins; do\n                               if command -v \"$b\" >/dev/null 2>&1; then st=\"$st$b:ok,\"\n                               else st=\"$st$b:GONE,\"; fi\n                             done\n                             echo {crate}=installed:\"$st\"\n                           fi\n                         else echo {missing}; fi",
            reg = sh_squote(&format!("^{crate_name} v")),
            awk = awk,
            noBins = sh_squote(&format!("{crate_name}=installed:NO-BINARIES-LISTED")),
            crate = crate_name,
            missing = sh_squote(&format!("{crate_name}=MISSING")),
        )
    });
    // The PATH repair goes FIRST: both `cargo install --list` and the
    // `command -v "$b"` below resolve through PATH, and this observable feeds
    // DRIFT, so its blindness costs a re-apply on every run (forjar#489).
    format!("{}\n{}", path_prelude(), queries)
}