rustpkg.rc

// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

// rustpkg - a purely function package manager and build system

#[link(name = "rustpkg",
       vers = "0.6",
       uuid = "25de5e6e-279e-4a20-845c-4cabae92daaf",
       url = "https://github.com/mozilla/rust/tree/master/src/librustpkg")];

#[license = "MIT/ASL2"];
#[crate_type = "lib"];
#[no_core];
#[allow(vecs_implicitly_copyable,
        non_implicitly_copyable_typarams)];

extern mod core(vers = "0.6");
extern mod std(vers = "0.6");
extern mod rustc(vers = "0.6");
extern mod syntax(vers = "0.6");

use core::*;
use core::hashmap::linear::LinearMap;
use core::io::{ReaderUtil, WriterUtil};
use rustc::driver::{driver, session};
use rustc::metadata::filesearch;
use std::net::url;
use std::{json, semver, getopts};
use syntax::codemap::spanned;
use syntax::{ast, attr, codemap, diagnostic, parse, visit};

mod usage;
mod util;

use util::Package;

struct PackageScript {
    id: ~str,
    name: ~str,
    vers: semver::Version,
    crates: ~[~str],
    deps: ~[(~str, Option<~str>)],
    input: driver::input,
    sess: session::Session,
    cfg: ast::crate_cfg,
    crate: @ast::crate,
    custom: bool
}

impl PackageScript {
    static fn parse(parent: &Path) -> Result<PackageScript, ~str> {
        let script = parent.push(~"pkg.rs");

        if !os::path_exists(&script) {
            return result::Err(~"no pkg.rs file");
        }

        let binary = os::args()[0];
        let options = @session::options {
            binary: binary,
            crate_type: session::bin_crate,
            .. *session::basic_options()
        };
        let input = driver::file_input(script);
        let sess = driver::build_session(options, diagnostic::emit);
        let cfg = driver::build_configuration(sess, binary, input);
        let (crate, _) = driver::compile_upto(sess, cfg, input,
                                              driver::cu_parse, None);
        let mut id = None;
        let mut vers = None;
        let mut crates = ~[];
        let mut deps = ~[];

        fn load_pkg_attr(mis: ~[@ast::meta_item]) -> (Option<~str>,
                                                      Option<~str>) {
            let mut id = None;
            let mut vers = None;

            for mis.each |a| {
                match a.node {
                    ast::meta_name_value(v, spanned {
                                                node: ast::lit_str(s),
                                                span: _}) => {
                        match *v {
                            ~"id" => id = Some(*s),
                            ~"vers" => vers = Some(*s),
                            _ => ()
                        }
                    }
                    _ => {}
                }
            }

            (id, vers)
        }

        fn load_pkg_dep_attr(mis: ~[@ast::meta_item]) -> (Option<~str>,
                                                          Option<~str>) {
            let mut url = None;
            let mut target = None;

            for mis.each |a| {
                match a.node {
                    ast::meta_name_value(v, spanned {
                                                node: ast::lit_str(s),
                                                span: _}) => {
                        match *v {
                            ~"url" => url = Some(*s),
                            ~"target" => target = Some(*s),
                            _ => ()
                        }
                    }
                    _ => {}
                }
            }

            (url, target)
        }

        fn load_pkg_crate_attr(mis: ~[@ast::meta_item]) -> Option<~str> {
            let mut file = None;

            for mis.each |a| {
                match a.node {
                    ast::meta_name_value(v, spanned {
                                                node: ast::lit_str(s),
                                                span: _}) => {
                        match *v {
                            ~"file" => file = Some(*s),
                            _ => ()
                        }
                    }
                    _ => {}
                }
            }

            file
        }

        for crate.node.attrs.each |a| {
            match a.node.value.node {
                ast::meta_list(v, mis) => {
                    match *v {
                        ~"pkg" => {
                            let (i, v) = load_pkg_attr(mis);

                            id = i;
                            vers = v;
                        }
                        ~"pkg_dep" => {
                            let (u, t) = load_pkg_dep_attr(mis);

                            if u.is_none() {
                                fail!(~"pkg_dep attr without a url value");
                            }

                            deps.push((u.get(), t));
                        }
                        ~"pkg_crate" => {
                            let f = load_pkg_crate_attr(mis);

                            if f.is_none() {
                                fail!(~"pkg_file attr without a file value");
                            }

                            crates.push(f.get());
                        }
                        _ => {}
                    }
                }
                _ => {}
            }
        }

        let mut custom = false;

        // If we hit a function, we assume they want to use
        // the build API.
        for crate.node.module.items.each |i| {
            match i.node {
                ast::item_fn(_, _, _, _) => {
                    custom = true;

                    break;
                }
                _ => {}
            }
        }

        if id.is_none() || vers.is_none() {
            return result::Err(~"pkg attr without (id, vers) values");
        }

        let id = id.get();
        let name = match util::parse_name(id) {
            result::Ok(name) => name,
            result::Err(err) => return result::Err(err)
        };
        let vers = match util::parse_vers(vers.get()) {
            result::Ok(vers) => vers,
            result::Err(err) => return result::Err(err)
        };

        result::Ok(PackageScript {
            id: id,
            name: name,
            vers: vers,
            crates: crates,
            deps: deps,
            input: input,
            sess: sess,
            cfg: cfg,
            crate: crate,
            custom: custom
        })
    }

    // Build the bootstrap and run a command
    // FIXME (#4432): Use workcache to only compile the script when changed
    fn run(&self, cmd: ~str, test: bool) -> int {
        let work_dir = self.work_dir();
        let input = self.input;
        let sess = self.sess;
        let cfg = self.cfg;
        let crate = util::ready_crate(sess, self.crate);
        let outputs = driver::build_output_filenames(input, &Some(work_dir),
                                                     &None, sess);
        let exe = work_dir.push(~"pkg" + util::exe_suffix());
        let root = filesearch::get_rustpkg_sysroot().get().pop().pop();

        driver::compile_rest(sess, cfg, driver::cu_parse,
                             Some(outputs), Some(crate));
        run::run_program(exe.to_str(), ~[root.to_str(), cmd, test.to_str()])
    }

    fn hash(&self) -> ~str {
        fmt!("%s-%s-%s", self.name, util::hash(self.id + self.vers.to_str()),
                         self.vers.to_str())
    }

    fn work_dir(&self) -> Path {
        util::root().push(~"work").push(self.hash())
    }
}

struct Ctx {
    cfgs: ~[~str],
    json: bool,
    dep_cache: @mut LinearMap<~str, bool>
}

impl Ctx {
    fn run(&self, cmd: ~str, args: ~[~str]) {
        let root = util::root();

        util::need_dir(&root);
        util::need_dir(&root.push(~"work"));
        util::need_dir(&root.push(~"lib"));
        util::need_dir(&root.push(~"bin"));
        util::need_dir(&root.push(~"tmp"));

        fn sep_name_vers(in: ~str) -> (Option<~str>, Option<~str>) {
            let mut name = None;
            let mut vers = None;
            let parts = str::split_char(in, '@');

            if parts.len() >= 1 {
                name = Some(parts[0]);

                if parts.len() >= 2 {
                    vers = Some(parts[1]);
                }
            }

            (name, vers)
        }

        match cmd {
            ~"build" => {
                if args.len() < 1 {
                    return usage::build();
                }
                let pkgid = PkgId::new(args[0]);
                let mut src = PkgSrc::new(&Path("."), &pkgid);
                src.find_crates();
                src.build(&Path("."));
            }
            ~"clean" => {
                self.clean();
            }
            ~"do" => {
                if args.len() < 1 {
                    return usage::do_cmd();
                }

                self.do_cmd(args[0]);
            }
            ~"info" => {
                self.info();
            }
            ~"install" => {
                self.install(if args.len() >= 1 { Some(args[0]) }
                             else { None },
                             if args.len() >= 2 { Some(args[1]) }
                             else { None }, false);
            }
            ~"prefer" => {
                if args.len() < 1 {
                    return usage::uninstall();
                }

                let (name, vers) = sep_name_vers(args[0]);

                self.prefer(name.get(), vers);
            }
            ~"test" => {
                self.test();
            }
            ~"uninstall" => {
                if args.len() < 1 {
                    return usage::uninstall();
                }

                let (name, vers) = sep_name_vers(args[0]);

                self.uninstall(name.get(), vers);
            }
            ~"unprefer" => {
                if args.len() < 1 {
                    return usage::uninstall();
                }

                let (name, vers) = sep_name_vers(args[0]);

                self.unprefer(name.get(), vers);
            }
            _ => fail!(~"reached an unhandled command")
        }
    }

    fn do_cmd(&self, cmd: ~str) -> bool {
        match cmd {
            ~"build" | ~"test" => {
                util::error(~"that command cannot be manually called");

                return false;
            }
            _ => {}
        }

        let cwd = &os::getcwd();
        let script = match PackageScript::parse(cwd) {
            result::Ok(script) => script,
            result::Err(err) => {
                util::error(err);

                return false;
            }
        };
        let status = script.run(cmd, false);

        if status == 42 {
            util::error(~"no fns are listening for that cmd");

            return false;
        }

        status == 0
    }

    fn build(&self, dir: &Path, verbose: bool, opt: bool,
             test: bool) -> Option<PackageScript> {
        let cwd = &os::getcwd();
        let script = match PackageScript::parse(dir) {
            result::Ok(script) => script,
            result::Err(err) => {
                util::error(err);

                return None;
            }
        };
        let work_dir = script.work_dir();
        let mut success = true;

        util::need_dir(&work_dir);

        if script.deps.len() >= 1 {
            util::note(~"installing dependencies");

            for script.deps.each |&dep| {
                let (url, target) = dep;

                success = self.install(Some(url), target, true);

                if !success { break; }
            }


            if !success {
                util::error(
                    fmt!("building %s v%s failed: a dep wasn't installed",
                         script.name, script.vers.to_str()));

                return None;
            }

            util::note(~"installed dependencies");
        }

        // Build imperative crates
        os::change_dir(dir);

        if script.custom {
            let status = script.run(~"build", test);

            if status != 0 && status != 42 {
                util::error(
                    fmt!("building %s v%s failed: custom logic failed (%d)",
                         script.name, script.vers.to_str(), status));

                return None;
            }
        }

        os::change_dir(cwd);

        for script.crates.each |&crate| {
            let crate = &dir.push_rel(&Path(crate)).normalize();

            util::note(fmt!("compiling %s", crate.to_str()));

            success = self.compile(crate, &work_dir, ~[],
                                   ~[], opt, test);

            if !success { break; }
        }

        if !success {
            util::error(
                fmt!("building %s v%s failed: a crate failed to compile",
                     script.name, script.vers.to_str()));

            return None;
        }

        if verbose {
            util::note(fmt!("built %s v%s", script.name,
                            script.vers.to_str()));
        }

        Some(script)
    }

    fn compile(&self, crate: &Path, dir: &Path, flags: ~[~str],
               cfgs: ~[~str], opt: bool, test: bool) -> bool {
        util::compile_crate(None, crate, dir, flags, cfgs, opt, test)
    }

    fn clean(&self) -> bool {
        let script = match PackageScript::parse(&os::getcwd()) {
            result::Ok(script) => script,
            result::Err(err) => {
                util::error(err);

                return false;
            }
        };
        let dir = script.work_dir();

        util::note(fmt!("cleaning %s v%s (%s)", script.name,
                        script.vers.to_str(), script.id));

        if os::path_exists(&dir) {
            util::remove_dir_r(&dir);
            util::note(fmt!("removed %s", dir.to_str()));
        }

        util::note(fmt!("cleaned %s v%s", script.name,
                                          script.vers.to_str()));

        true
    }

    fn info(&self) {
        if self.json {
            match PackageScript::parse(&os::getcwd()) {
                result::Ok(script) => {
                    let mut map = ~LinearMap::new();

                    map.insert(~"id", json::String(script.id));
                    map.insert(~"name", json::String(script.name));
                    map.insert(~"vers", json::String(script.vers.to_str()));
                    map.insert(~"deps", json::List(do script.deps.map |&dep| {
                        let (url, target) = dep;
                        let mut inner = ~LinearMap::new();

                        inner.insert(~"url", json::String(url));

                        if !target.is_none() {
                            inner.insert(~"target",
                                         json::String(target.get()));
                        }

                        json::Object(inner)
                    }));

                    io::println(json::to_pretty_str(&json::Object(map)));
                }
                result::Err(_) => io::println(~"{}")
            }
        } else {
            let script = match PackageScript::parse(&os::getcwd()) {
                result::Ok(script) => script,
                result::Err(err) => {
                    util::error(err);

                    return;
                }
            };

            util::note(fmt!("id: %s", script.id));
            util::note(fmt!("name: %s", script.name));
            util::note(fmt!("vers: %s", script.vers.to_str()));
            util::note(fmt!("deps: %s",
                            if script.deps.len() > 0 {
                                ~""
                            } else {
                                ~"none"
                            }));

            for script.deps.each |&dep| {
                let (url, target) = dep;

                util::note(fmt!("  <%s> (%s)", url, match target {
                    Some(target) => target,
                    None => ~""
                }));
            }
        }
    }

    fn install(&self, url: Option<~str>,
               target: Option<~str>, cache: bool) -> bool {
        let mut success;
        let mut dir;

        if url.is_none() {
            util::note(~"installing from the cwd");

            dir = os::getcwd();
        } else {
            let url = url.get();
            let hash = util::hash(if !target.is_none() { url + target.get() }
                                  else { url });

            if self.dep_cache.contains_key(&hash) {
                util::warn(~"already installed dep this run");

                return true;
            }

            self.dep_cache.insert(hash, true);

            dir = util::root().push(~"tmp").push(hash);

            if cache && os::path_exists(&dir) {
                return true;
            }

            success = self.fetch(&dir, url, target);

            if !success {
                return false;
            }
        }

        let script = match self.build(&dir, false, true, false) {
            Some(script) => script,
            None => {
                return false;
            }
        };
        let work_dir = script.work_dir();
        let from_bin_dir = work_dir.push(~"bin");
        let from_lib_dir = work_dir.push(~"lib");
        let to_bin_dir = util::root().push(~"bin");
        let to_lib_dir = util::root().push(~"lib");
        let mut bins = ~[];
        let mut libs = ~[];

        for os::walk_dir(&from_bin_dir) |bin| {
            let to = to_bin_dir.push_rel(&bin.file_path());

            os::copy_file(bin, &to);
            bins.push(to.to_str());
        }

        for os::walk_dir(&from_lib_dir) |lib| {
            let to = to_lib_dir.push_rel(&lib.file_path());

            os::copy_file(lib, &to);
            libs.push(to.to_str());
        }

        let package = Package {
            id: script.id,
            vers: script.vers,
            bins: bins,
            libs: libs
        };

        util::note(fmt!("installed %s v%s", script.name,
                                            script.vers.to_str()));
        util::add_pkg(&package);

        true
    }

    fn fetch(&self, dir: &Path, url: ~str, target: Option<~str>) -> bool {
        let url = if str::find_str(url, "://").is_none() {
            ~"http://" + url }
        else { url };
        let url = match url::from_str(url) {
            result::Ok(url) => url,
            result::Err(err) => {
                util::error(fmt!("failed parsing %s", err.to_lower()));

                return false;
            }
        };
        let str = url.to_str();

        match Path(url.path).filetype() {
            Some(ext) => {
                if ext == ~".git" {
                    return self.fetch_git(dir, str, target);
                }
            }
            None => {}
        }

        match url.scheme {
            ~"git" => self.fetch_git(dir, str, target),
            ~"http" | ~"ftp" | ~"file" => self.fetch_curl(dir, str),
            _ => {
                util::warn(~"unknown url scheme to fetch, using curl");
                self.fetch_curl(dir, str)
            }
        }
    }

    fn fetch_curl(&self, dir: &Path, url: ~str) -> bool {
        util::note(fmt!("fetching from %s using curl", url));

        let tar = dir.dir_path().push(&dir.file_path().to_str() + ~".tar");

        if run::program_output(~"curl", ~[~"-f", ~"-s",
                                          ~"-o", tar.to_str(),
                                          url]).status != 0 {
            util::error(~"fetching failed: downloading using curl failed");

            return false;
        }

        if run::program_output(~"tar", ~[~"-x", ~"--strip-components=1",
                                         ~"-C", dir.to_str(), ~"-f",
                                         tar.to_str()]).status != 0 {
            util::error(~"fetching failed: extracting using tar failed" +
                        ~"(is it a valid tar archive?)");

            return false;
        }

        true
    }

    fn fetch_git(&self, dir: &Path, url: ~str, target: Option<~str>) -> bool {
        util::note(fmt!("fetching from %s using git", url));

        // Git can't clone into a non-empty directory
        util::remove_dir_r(dir);

        if run::program_output(~"git", ~[~"clone", url,
                                         dir.to_str()]).status != 0 {
            util::error(~"fetching failed: can't clone repository");

            return false;
        }

        if !target.is_none() {
            let mut success = true;

            do util::temp_change_dir(dir) {
                success = run::program_output(~"git",
                                              ~[~"checkout",
                                                target.get()]).status != 0
            }

            if !success {
                util::error(~"fetching failed: can't checkout target");

                return false;
            }
        }

        true
    }

    fn prefer(&self, id: ~str, vers: Option<~str>) -> bool {
        let package = match util::get_pkg(id, vers) {
            result::Ok(package) => package,
            result::Err(err) => {
                util::error(err);

                return false;
            }
        };
        let name = match util::parse_name(package.id) {
            result::Ok(name) => name,
            result::Err(err) => {
                util::error(err);

                return false;
            }
        };

        util::note(fmt!("preferring %s v%s (%s)", name, package.vers.to_str(),
                                                  package.id));

        let bin_dir = util::root().push(~"bin");

        for package.bins.each |&bin| {
            let path = Path(bin);
            let name = str::split_char(path.file_path().to_str(), '-')[0];
            let out = bin_dir.push(name);

            util::link_exe(&path, &out);
            util::note(fmt!("linked %s", out.to_str()));
        }

        util::note(fmt!("preferred %s v%s", name, package.vers.to_str()));

        true
    }

    fn test(&self) -> bool {
        let script = match self.build(&os::getcwd(), false, false, true) {
            Some(script) => script,
            None => {
                return false;
            }
        };
        let work_dir = script.work_dir();
        let test_dir = work_dir.push(~"test");

        for os::walk_dir(&test_dir) |test| {
            util::note(fmt!("running %s", test.to_str()));

            let status = run::run_program(test.to_str(), ~[]);

            if status != 0 {
                os::set_exit_status(status);
            }
        }

        // Run custom test listener
        if script.custom {
            let status = script.run(~"test", false);

            if status != 0 && status != 42 {
                util::error(
                    fmt!("testing %s v%s failed: custom logic failed (%d)",
                         script.name, script.vers.to_str(), status));

                os::set_exit_status(status);
            }
        }

        util::note(fmt!("tested %s v%s", script.name, script.vers.to_str()));

        true
    }

    fn uninstall(&self, id: ~str, vers: Option<~str>) -> bool {
        let package = match util::get_pkg(id, vers) {
            result::Ok(package) => package,
            result::Err(err) => {
                util::error(err);

                return false;
            }
        };
        let name = match util::parse_name(package.id) {
            result::Ok(name) => name,
            result::Err(err) => {
                util::error(err);

                return false;
            }
        };

        util::note(fmt!("uninstalling %s v%s (%s)", name,
                        package.vers.to_str(), package.id));

        for vec::append(package.bins, package.libs).each |&file| {
            let path = Path(file);

            if os::path_exists(&path) {
                if os::remove_file(&path) {
                    util::note(fmt!("removed %s", path.to_str()));
                } else {
                    util::error(fmt!("could not remove %s", path.to_str()));
                }
            }
        }

        util::note(fmt!("uninstalled %s v%s", name, package.vers.to_str()));
        util::remove_pkg(&package);

        true
    }

    fn unprefer(&self, id: ~str, vers: Option<~str>) -> bool {
        let package = match util::get_pkg(id, vers) {
            result::Ok(package) => package,
            result::Err(err) => {
                util::error(err);

                return false;
            }
        };
        let name = match util::parse_name(package.id) {
            result::Ok(name) => name,
            result::Err(err) => {
                util::error(err);

                return false;
            }
        };

        util::note(fmt!("unpreferring %s v%s (%s)", name,
                        package.vers.to_str(), package.id));

        let bin_dir = util::root().push(~"bin");

        for package.bins.each |&bin| {
            let path = Path(bin);
            let name = str::split_char(path.file_path().to_str(), '-')[0];
            let out = bin_dir.push(name);

            if os::path_exists(&out) {
                if os::remove_file(&out) {
                    util::note(fmt!("unlinked %s", out.to_str()));
                } else {
                    util::error(fmt!("could not unlink %s", out.to_str()));
                }
            }
        }

        util::note(fmt!("unpreferred %s v%s", name, package.vers.to_str()));

        true
    }
}

pub fn main() {
    let args = os::args();
    let opts = ~[getopts::optflag(~"h"), getopts::optflag(~"help"),
                 getopts::optflag(~"j"), getopts::optflag(~"json"),
                 getopts::optmulti(~"c"), getopts::optmulti(~"cfg")];
    let matches = &match getopts::getopts(args, opts) {
        result::Ok(m) => m,
        result::Err(f) => {
            util::error(fmt!("%s", getopts::fail_str(f)));

            return;
        }
    };
    let help = getopts::opt_present(matches, ~"h") ||
               getopts::opt_present(matches, ~"help");
    let json = getopts::opt_present(matches, ~"j") ||
               getopts::opt_present(matches, ~"json");
    let cfgs = vec::append(getopts::opt_strs(matches, ~"cfg"),
                           getopts::opt_strs(matches, ~"c"));
    let mut args = copy matches.free;

    args.shift();

    if (args.len() < 1) {
        return usage::general();
    }

    let cmd = args.shift();

    if !util::is_cmd(cmd) {
        return usage::general();
    } else if help {
        return match cmd {
            ~"build" => usage::build(),
            ~"clean" => usage::clean(),
            ~"do" => usage::do_cmd(),
            ~"info" => usage::info(),
            ~"install" => usage::install(),
            ~"prefer" => usage::prefer(),
            ~"test" => usage::test(),
            ~"uninstall" => usage::uninstall(),
            ~"unprefer" => usage::unprefer(),
            _ => usage::general()
        };
    }

    Ctx {
        cfgs: cfgs,
        json: json,
        dep_cache: @mut LinearMap::new()
    }.run(cmd, args);
}

/// A crate is a unit of Rust code to be compiled into a binary or library
pub struct Crate {
    file: Path,
    flags: ~[~str],
    cfgs: ~[~str]
}

pub struct Listener {
    cmds: ~[~str],
    cb: ~fn()
}

pub fn run(listeners: ~[Listener]) {
    let rcmd = os::args()[2];
    let mut found = false;

    for listeners.each |listener| {
        for listener.cmds.each |&cmd| {
            if cmd == rcmd {
                (listener.cb)();

                found = true;

                break;
            }
        }
    }

    if !found {
        os::set_exit_status(42);
    }
}

pub impl Crate {

    static fn new(p: &Path) -> Crate {
        Crate {
            file: copy *p,
            flags: ~[],
            cfgs: ~[]
        }
    }

    fn flag(&self, flag: ~str) -> Crate {
        Crate {
            flags: vec::append(copy self.flags, ~[flag]),
            .. copy *self
        }
    }

    fn flags(&self, flags: ~[~str]) -> Crate {
        Crate {
            flags: vec::append(copy self.flags, flags),
            .. copy *self
        }
    }

    fn cfg(&self, cfg: ~str) -> Crate {
        Crate {
            cfgs: vec::append(copy self.cfgs, ~[cfg]),
            .. copy *self
        }
    }

    fn cfgs(&self, cfgs: ~[~str]) -> Crate {
        Crate {
            cfgs: vec::append(copy self.cfgs, cfgs),
            .. copy *self
        }
    }
}

/**
 * Get the working directory of the package script.
 * Assumes that the package script has been compiled
 * in is the working directory.
 */
pub fn work_dir() -> Path {
    os::self_exe_path().get()
}

/**
 * Get the source directory of the package (i.e.
 * where the crates are located). Assumes
 * that the cwd is changed to it before
 * running this executable.
 */
pub fn src_dir() -> Path {
    os::getcwd()
}

/// Build a set of crates, should be called once
pub fn build(crates: ~[Crate]) -> bool {
    let args = os::args();
    let dir = src_dir();
    let work_dir = work_dir();
    let mut success = true;
    let sysroot = Path(args[1]);
    let test = args[3] == ~"true";

    for crates.each |&crate| {
        let path = &dir.push_rel(&crate.file).normalize();

        util::note(fmt!("compiling %s", path.to_str()));

        success = util::compile_crate(Some(sysroot), path, &work_dir,
                                      crate.flags, crate.cfgs,
                                      false, test);

        if !success { break; }
    }

    if !success {
        os::set_exit_status(101);
    }

    success
}


// Path-fragment identifier of a package such as 
// 'github.com/graydon/test'; must be a relative
// path with >=1 component.
struct PkgId {
    path: Path
}

condition! {
    bad_pkg_id: (::core::path::Path, ~str) -> ::PkgId;
}

impl PkgId {
    static fn new(s: &str) -> PkgId {
        use bad_pkg_id::cond;

        let p = Path(s);
        if p.is_absolute {
            return cond.raise((p, ~"absolute pkgid"));
        }
        if p.components.len() < 1 {
            return cond.raise((p, ~"0-length pkgid"));
        }
        PkgId {
            path: p
        }
    }
}


// An enumeration of the unpacked source of a package workspace.
// This contains a list of files found in the source workspace.
pub struct PkgSrc {
    root: Path,
    id: PkgId,
    libs: ~[Crate],
    mains: ~[Crate],
    tests: ~[Crate],
    benchs: ~[Crate],
}

condition! {
    bad_path: (::core::path::Path, ~str) -> ::core::path::Path;
}

condition! {
    build_err: (~str) -> ();
}

impl PkgSrc {


    static fn new(fs_root: &Path, id: &PkgId) -> PkgSrc {
        PkgSrc {
            root: copy *fs_root,
            id: copy *id,
            libs: ~[],
            mains: ~[],
            tests: ~[],
            benchs: ~[]
        }
    }


    fn check_dir(&self) -> Path {
        use bad_path::cond;

        let dir = self.root.push_rel(&self.id.path).normalize();

        if ! os::path_exists(&dir) {
            return cond.raise((dir, ~"missing package dir"));
        }
              
        if ! os::path_is_dir(&dir) {
            return cond.raise((dir, ~"missing package dir"));
        }

        dir
    }


    fn has_pkg_file(&self) -> bool {
        let dir = self.check_dir();
        dir.push("pkg.rs").exists()
    }


    static fn push_crate(cs: &mut ~[Crate], prefix: uint, p: &Path) {
        assert p.components.len() > prefix;
        let mut sub = Path("");
        for vec::slice(p.components, prefix,
                       p.components.len()).each |c| {
            sub = sub.push(*c);
        }
        debug!("found crate %s", sub.to_str());
        cs.push(Crate::new(&sub));
    }

    fn find_crates(&mut self) {
        use PkgSrc::push_crate;
        assert ! self.has_pkg_file();
        let dir = self.check_dir();
        let prefix = dir.components.len();
        for os::walk_dir(&dir) |pth| {
            match pth.filename() {
                Some(~"lib.rs") => push_crate(&mut self.libs,
                                              prefix, pth),
                Some(~"main.rs") => push_crate(&mut self.mains,
                                               prefix, pth),
                Some(~"test.rs") => push_crate(&mut self.tests,
                                               prefix, pth),
                Some(~"bench.rs") => push_crate(&mut self.benchs,
                                                prefix, pth),
                _ => ()
            }
        }
        debug!("found %u libs, %u mains, %u tests, %u benchs",
               self.libs.len(),
               self.mains.len(),
               self.tests.len(),
               self.benchs.len())
    }


    static fn build_crates(dst_dir: &Path,
                           src_dir: &Path,
                           crates: &[Crate],
                           test: bool) {

        for crates.each |&crate| {
            let path = &src_dir.push_rel(&crate.file).normalize();
            util::note(fmt!("compiling %s", path.to_str()));
            if ! util::compile_crate(None, path,
                                     dst_dir,
                                     crate.flags,
                                     crate.cfgs,
                                     false, test) {
                build_err::cond.raise(fmt!("build failure on %s",
                                           path.to_str()));
            }
        }
    }

    fn build(&self, dst_dir: &Path) {
        let dir = self.check_dir();
        PkgSrc::build_crates(dst_dir, &dir, self.libs, false);
        PkgSrc::build_crates(dst_dir, &dir, self.mains, false);
        PkgSrc::build_crates(dst_dir, &dir, self.tests, true);
        PkgSrc::build_crates(dst_dir, &dir, self.benchs, true);
    }
}