fd/src/exec/mod.rs

587 lines
19 KiB
Rust

mod command;
mod input;
mod job;
mod token;
use std::borrow::Cow;
use std::ffi::{OsStr, OsString};
use std::io;
use std::iter;
use std::path::{Component, Path, PathBuf, Prefix};
use std::process::Stdio;
use std::sync::{Arc, Mutex};
use anyhow::{bail, Result};
use argmax::Command;
use once_cell::sync::Lazy;
use regex::Regex;
use crate::exit_codes::ExitCode;
use self::command::{execute_commands, handle_cmd_error};
use self::input::{basename, dirname, remove_extension};
pub use self::job::{batch, job};
use self::token::Token;
/// Execution mode of the command
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum ExecutionMode {
/// Command is executed for each search result
OneByOne,
/// Command is run for a batch of results at once
Batch,
}
#[derive(Debug, Clone, PartialEq)]
pub struct CommandSet {
mode: ExecutionMode,
commands: Vec<CommandTemplate>,
}
impl CommandSet {
pub fn new<I, S>(input: I) -> Result<CommandSet>
where
I: IntoIterator<Item = Vec<S>>,
S: AsRef<str>,
{
Ok(CommandSet {
mode: ExecutionMode::OneByOne,
commands: input
.into_iter()
.map(CommandTemplate::new)
.collect::<Result<_>>()?,
})
}
pub fn new_batch<I, S>(input: I) -> Result<CommandSet>
where
I: IntoIterator<Item = Vec<S>>,
S: AsRef<str>,
{
Ok(CommandSet {
mode: ExecutionMode::Batch,
commands: input
.into_iter()
.map(|args| {
let cmd = CommandTemplate::new(args)?;
if cmd.number_of_tokens() > 1 {
bail!("Only one placeholder allowed for batch commands");
}
if cmd.args[0].has_tokens() {
bail!("First argument of exec-batch is expected to be a fixed executable");
}
Ok(cmd)
})
.collect::<Result<Vec<_>>>()?,
})
}
pub fn in_batch_mode(&self) -> bool {
self.mode == ExecutionMode::Batch
}
pub fn execute(
&self,
input: &Path,
path_separator: Option<&str>,
out_perm: Arc<Mutex<()>>,
buffer_output: bool,
) -> ExitCode {
let commands = self
.commands
.iter()
.map(|c| c.generate(input, path_separator));
execute_commands(commands, &out_perm, buffer_output)
}
pub fn execute_batch<I>(&self, paths: I, limit: usize, path_separator: Option<&str>) -> ExitCode
where
I: Iterator<Item = PathBuf>,
{
let builders: io::Result<Vec<_>> = self
.commands
.iter()
.map(|c| CommandBuilder::new(c, limit))
.collect();
match builders {
Ok(mut builders) => {
for path in paths {
for builder in &mut builders {
if let Err(e) = builder.push(&path, path_separator) {
return handle_cmd_error(Some(&builder.cmd), e);
}
}
}
for builder in &mut builders {
if let Err(e) = builder.finish() {
return handle_cmd_error(Some(&builder.cmd), e);
}
}
ExitCode::Success
}
Err(e) => handle_cmd_error(None, e),
}
}
}
/// Represents a multi-exec command as it is built.
#[derive(Debug)]
struct CommandBuilder {
pre_args: Vec<OsString>,
path_arg: ArgumentTemplate,
post_args: Vec<OsString>,
cmd: Command,
count: usize,
limit: usize,
}
impl CommandBuilder {
fn new(template: &CommandTemplate, limit: usize) -> io::Result<Self> {
let mut pre_args = vec![];
let mut path_arg = None;
let mut post_args = vec![];
for arg in &template.args {
if arg.has_tokens() {
path_arg = Some(arg.clone());
} else if path_arg == None {
pre_args.push(arg.generate("", None));
} else {
post_args.push(arg.generate("", None));
}
}
let cmd = Self::new_command(&pre_args)?;
Ok(Self {
pre_args,
path_arg: path_arg.unwrap(),
post_args,
cmd,
count: 0,
limit,
})
}
fn new_command(pre_args: &[OsString]) -> io::Result<Command> {
let mut cmd = Command::new(&pre_args[0]);
cmd.stdin(Stdio::inherit());
cmd.stdout(Stdio::inherit());
cmd.stderr(Stdio::inherit());
cmd.try_args(&pre_args[1..])?;
Ok(cmd)
}
fn push(&mut self, path: &Path, separator: Option<&str>) -> io::Result<()> {
if self.limit > 0 && self.count >= self.limit {
self.finish()?;
}
let arg = self.path_arg.generate(path, separator);
if !self
.cmd
.args_would_fit(iter::once(&arg).chain(&self.post_args))
{
self.finish()?;
}
self.cmd.try_arg(arg)?;
self.count += 1;
Ok(())
}
fn finish(&mut self) -> io::Result<()> {
if self.count > 0 {
self.cmd.try_args(&self.post_args)?;
self.cmd.status()?;
self.cmd = Self::new_command(&self.pre_args)?;
self.count = 0;
}
Ok(())
}
}
/// Represents a template that is utilized to generate command strings.
///
/// The template is meant to be coupled with an input in order to generate a command. The
/// `generate_and_execute()` method will be used to generate a command and execute it.
#[derive(Debug, Clone, PartialEq)]
struct CommandTemplate {
args: Vec<ArgumentTemplate>,
}
impl CommandTemplate {
fn new<I, S>(input: I) -> Result<CommandTemplate>
where
I: IntoIterator<Item = S>,
S: AsRef<str>,
{
static PLACEHOLDER_PATTERN: Lazy<Regex> =
Lazy::new(|| Regex::new(r"\{(/?\.?|//)\}").unwrap());
let mut args = Vec::new();
let mut has_placeholder = false;
for arg in input {
let arg = arg.as_ref();
let mut tokens = Vec::new();
let mut start = 0;
for placeholder in PLACEHOLDER_PATTERN.find_iter(arg) {
// Leading text before the placeholder.
if placeholder.start() > start {
tokens.push(Token::Text(arg[start..placeholder.start()].to_owned()));
}
start = placeholder.end();
match placeholder.as_str() {
"{}" => tokens.push(Token::Placeholder),
"{.}" => tokens.push(Token::NoExt),
"{/}" => tokens.push(Token::Basename),
"{//}" => tokens.push(Token::Parent),
"{/.}" => tokens.push(Token::BasenameNoExt),
_ => unreachable!("Unhandled placeholder"),
}
has_placeholder = true;
}
// Without a placeholder, the argument is just fixed text.
if tokens.is_empty() {
args.push(ArgumentTemplate::Text(arg.to_owned()));
continue;
}
if start < arg.len() {
// Trailing text after last placeholder.
tokens.push(Token::Text(arg[start..].to_owned()));
}
args.push(ArgumentTemplate::Tokens(tokens));
}
// We need to check that we have at least one argument, because if not
// it will try to execute each file and directory it finds.
//
// Sadly, clap can't currently handle this for us, see
// https://github.com/clap-rs/clap/issues/3542
if args.is_empty() {
bail!("No executable provided for --exec or --exec-batch");
}
// If a placeholder token was not supplied, append one at the end of the command.
if !has_placeholder {
args.push(ArgumentTemplate::Tokens(vec![Token::Placeholder]));
}
Ok(CommandTemplate { args })
}
fn number_of_tokens(&self) -> usize {
self.args.iter().filter(|arg| arg.has_tokens()).count()
}
/// Generates and executes a command.
///
/// Using the internal `args` field, and a supplied `input` variable, a `Command` will be
/// build.
fn generate(&self, input: &Path, path_separator: Option<&str>) -> io::Result<Command> {
let mut cmd = Command::new(self.args[0].generate(&input, path_separator));
for arg in &self.args[1..] {
cmd.try_arg(arg.generate(&input, path_separator))?;
}
Ok(cmd)
}
}
/// Represents a template for a single command argument.
///
/// The argument is either a collection of `Token`s including at least one placeholder variant, or
/// a fixed text.
#[derive(Clone, Debug, PartialEq)]
enum ArgumentTemplate {
Tokens(Vec<Token>),
Text(String),
}
impl ArgumentTemplate {
pub fn has_tokens(&self) -> bool {
matches!(self, ArgumentTemplate::Tokens(_))
}
/// Generate an argument from this template. If path_separator is Some, then it will replace
/// the path separator in all placeholder tokens. Text arguments and tokens are not affected by
/// path separator substitution.
pub fn generate(&self, path: impl AsRef<Path>, path_separator: Option<&str>) -> OsString {
use self::Token::*;
let path = path.as_ref();
match *self {
ArgumentTemplate::Tokens(ref tokens) => {
let mut s = OsString::new();
for token in tokens {
match *token {
Basename => s.push(Self::replace_separator(basename(path), path_separator)),
BasenameNoExt => s.push(Self::replace_separator(
&remove_extension(basename(path).as_ref()),
path_separator,
)),
NoExt => s.push(Self::replace_separator(
&remove_extension(path),
path_separator,
)),
Parent => s.push(Self::replace_separator(&dirname(path), path_separator)),
Placeholder => {
s.push(Self::replace_separator(path.as_ref(), path_separator))
}
Text(ref string) => s.push(string),
}
}
s
}
ArgumentTemplate::Text(ref text) => OsString::from(text),
}
}
/// Replace the path separator in the input with the custom separator string. If path_separator
/// is None, simply return a borrowed Cow<OsStr> of the input. Otherwise, the input is
/// interpreted as a Path and its components are iterated through and re-joined into a new
/// OsString.
fn replace_separator<'a>(path: &'a OsStr, path_separator: Option<&str>) -> Cow<'a, OsStr> {
// fast-path - no replacement necessary
if path_separator.is_none() {
return Cow::Borrowed(path);
}
let path_separator = path_separator.unwrap();
let mut out = OsString::with_capacity(path.len());
let mut components = Path::new(path).components().peekable();
while let Some(comp) = components.next() {
match comp {
// Absolute paths on Windows are tricky. A Prefix component is usually a drive
// letter or UNC path, and is usually followed by RootDir. There are also
// "verbatim" prefixes beginning with "\\?\" that skip normalization. We choose to
// ignore verbatim path prefixes here because they're very rare, might be
// impossible to reach here, and there's no good way to deal with them. If users
// are doing something advanced involving verbatim windows paths, they can do their
// own output filtering with a tool like sed.
Component::Prefix(prefix) => {
if let Prefix::UNC(server, share) = prefix.kind() {
// Prefix::UNC is a parsed version of '\\server\share'
out.push(path_separator);
out.push(path_separator);
out.push(server);
out.push(path_separator);
out.push(share);
} else {
// All other Windows prefix types are rendered as-is. This results in e.g. "C:" for
// drive letters. DeviceNS and Verbatim* prefixes won't have backslashes converted,
// but they're not returned by directories fd can search anyway so we don't worry
// about them.
out.push(comp.as_os_str());
}
}
// Root directory is always replaced with the custom separator.
Component::RootDir => out.push(path_separator),
// Everything else is joined normally, with a trailing separator if we're not last
_ => {
out.push(comp.as_os_str());
if components.peek().is_some() {
out.push(path_separator);
}
}
}
}
Cow::Owned(out)
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn tokens_with_placeholder() {
assert_eq!(
CommandSet::new(vec![vec![&"echo", &"${SHELL}:"]]).unwrap(),
CommandSet {
commands: vec![CommandTemplate {
args: vec![
ArgumentTemplate::Text("echo".into()),
ArgumentTemplate::Text("${SHELL}:".into()),
ArgumentTemplate::Tokens(vec![Token::Placeholder]),
]
}],
mode: ExecutionMode::OneByOne,
}
);
}
#[test]
fn tokens_with_no_extension() {
assert_eq!(
CommandSet::new(vec![vec!["echo", "{.}"]]).unwrap(),
CommandSet {
commands: vec![CommandTemplate {
args: vec![
ArgumentTemplate::Text("echo".into()),
ArgumentTemplate::Tokens(vec![Token::NoExt]),
],
}],
mode: ExecutionMode::OneByOne,
}
);
}
#[test]
fn tokens_with_basename() {
assert_eq!(
CommandSet::new(vec![vec!["echo", "{/}"]]).unwrap(),
CommandSet {
commands: vec![CommandTemplate {
args: vec![
ArgumentTemplate::Text("echo".into()),
ArgumentTemplate::Tokens(vec![Token::Basename]),
],
}],
mode: ExecutionMode::OneByOne,
}
);
}
#[test]
fn tokens_with_parent() {
assert_eq!(
CommandSet::new(vec![vec!["echo", "{//}"]]).unwrap(),
CommandSet {
commands: vec![CommandTemplate {
args: vec![
ArgumentTemplate::Text("echo".into()),
ArgumentTemplate::Tokens(vec![Token::Parent]),
],
}],
mode: ExecutionMode::OneByOne,
}
);
}
#[test]
fn tokens_with_basename_no_extension() {
assert_eq!(
CommandSet::new(vec![vec!["echo", "{/.}"]]).unwrap(),
CommandSet {
commands: vec![CommandTemplate {
args: vec![
ArgumentTemplate::Text("echo".into()),
ArgumentTemplate::Tokens(vec![Token::BasenameNoExt]),
],
}],
mode: ExecutionMode::OneByOne,
}
);
}
#[test]
fn tokens_multiple() {
assert_eq!(
CommandSet::new(vec![vec!["cp", "{}", "{/.}.ext"]]).unwrap(),
CommandSet {
commands: vec![CommandTemplate {
args: vec![
ArgumentTemplate::Text("cp".into()),
ArgumentTemplate::Tokens(vec![Token::Placeholder]),
ArgumentTemplate::Tokens(vec![
Token::BasenameNoExt,
Token::Text(".ext".into())
]),
],
}],
mode: ExecutionMode::OneByOne,
}
);
}
#[test]
fn tokens_single_batch() {
assert_eq!(
CommandSet::new_batch(vec![vec!["echo", "{.}"]]).unwrap(),
CommandSet {
commands: vec![CommandTemplate {
args: vec![
ArgumentTemplate::Text("echo".into()),
ArgumentTemplate::Tokens(vec![Token::NoExt]),
],
}],
mode: ExecutionMode::Batch,
}
);
}
#[test]
fn tokens_multiple_batch() {
assert!(CommandSet::new_batch(vec![vec!["echo", "{.}", "{}"]]).is_err());
}
#[test]
fn template_no_args() {
assert!(CommandTemplate::new::<Vec<_>, &'static str>(vec![]).is_err());
}
#[test]
fn command_set_no_args() {
assert!(CommandSet::new(vec![vec!["echo"], vec![]]).is_err());
}
#[test]
fn generate_custom_path_separator() {
let arg = ArgumentTemplate::Tokens(vec![Token::Placeholder]);
macro_rules! check {
($input:expr, $expected:expr) => {
assert_eq!(arg.generate($input, Some("#")), OsString::from($expected));
};
}
check!("foo", "foo");
check!("foo/bar", "foo#bar");
check!("/foo/bar/baz", "#foo#bar#baz");
}
#[cfg(windows)]
#[test]
fn generate_custom_path_separator_windows() {
let arg = ArgumentTemplate::Tokens(vec![Token::Placeholder]);
macro_rules! check {
($input:expr, $expected:expr) => {
assert_eq!(arg.generate($input, Some("#")), OsString::from($expected));
};
}
// path starting with a drive letter
check!(r"C:\foo\bar", "C:#foo#bar");
// UNC path
check!(r"\\server\share\path", "##server#share#path");
// Drive Relative path - no separator after the colon omits the RootDir path component.
// This is uncommon, but valid
check!(r"C:foo\bar", "C:foo#bar");
// forward slashes should get normalized and interpreted as separators
check!("C:/foo/bar", "C:#foo#bar");
check!("C:foo/bar", "C:foo#bar");
// Rust does not interpret "//server/share" as a UNC path, but rather as a normal
// absolute path that begins with RootDir, and the two slashes get combined together as
// a single path separator during normalization.
//check!("//server/share/path", "##server#share#path");
}
}