improved redirection handling

This commit is contained in:
Daniel Bulant 2023-08-06 16:01:39 +02:00
parent 5be4e36e3d
commit 3064ba5b17
2 changed files with 209 additions and 140 deletions

View file

@ -1,11 +1,45 @@
use std::fs::File;
use std::process::{Command};
use std::io::Read;
use std::process::Command;
use std::thread;
use crate::parser::ast::{AndExpression, BreakExpression, CommandValue, Expression, FileSourceExpression, FileTargetExpression, ForExpression, IfExpression, LetExpression, OrExpression, RedirectTargetExpression, Value, WhileExpression};
use crate::parser::vars::{AnyFunction, Context, Variable};
use crate::parser::vars::{AnyFunction, Context, ReaderOverride, Variable, WriterOverride};
use anyhow::{Result, bail, Context as AnyhowContext};
#[derive(Debug, Default)]
struct ExecResult {
commands: Vec<Command>
}
impl ExecResult {
fn exec(self, ctx: &mut Context) -> Result<Option<i32>> {
let mut children = Vec::new();
for mut command in self.commands {
let name = command.get_program().to_str().unwrap_or("unknown").to_string();
let out = command.spawn()
.with_context(|| "Failed to spawn process ".to_string() + &name)?;
drop(command);
children.push(out);
}
let mut code = None;
for mut child in children {
let out = child.wait()
.with_context(|| "Command failed")?;
code = Some(out.code().unwrap_or(-1));
}
if let Some(code) = code {
ctx.set_var(String::from("?"), Variable::I32(code));
}
Ok(code)
}
fn merge(&mut self, mut other: ExecResult) {
self.commands.append(&mut other.commands);
}
}
trait ExecExpression {
fn exec(&mut self, ctx: &mut Context) -> Result<Option<Command>>;
fn exec(&mut self, ctx: &mut Context) -> Result<ExecResult>;
}
trait GetValue {
@ -30,19 +64,22 @@ impl GetValue for Value {
Value::Variable(str) => Ok(ctx.get_var(str).unwrap_or(&mut Variable::String(String::from(""))).clone()),
Value::ArrayVariable(str) => Ok(ctx.get_var(str).unwrap_or(&mut Variable::Array(Vec::new())).clone()),
Value::Expressions(expressions) => {
let mut out = String::new();
ctx.add_scope();
for expr in expressions {
let res = expr.exec(ctx)?;
match res {
None => {},
Some(mut cmd) => {
out += &*String::from_utf8_lossy(&cmd.output().with_context(|| "Failed to read output of command")?.stdout);
}
}
}
let (mut reader, writer) = os_pipe::pipe()?;
let mut data = String::new();
thread::scope(|s| -> Result<()> {
ctx.scopes.last_mut().unwrap().stdout_override = Some(WriterOverride::Pipe(writer));
s.spawn(|| -> Result<()> {
let mut buf = Vec::new();
reader.read_to_end(&mut buf)?;
data = String::from_utf8_lossy(&buf).to_string();
Ok(())
});
expressions.exec(ctx)?.exec(ctx)?;
Ok(())
})?;
ctx.pop_scope();
Ok(Variable::String(out))
Ok(Variable::String(data))
},
Value::Values(vec) | Value::ArrayDefinition(vec) => {
let mut out = Vec::new();
@ -74,7 +111,7 @@ fn get_variables(ctx: &mut Context, args: &mut Vec<Value>) -> Result<Vec<Variabl
}
impl ExecExpression for Expression {
fn exec(self: &mut Expression, ctx: &mut Context) -> Result<Option<Command>> {
fn exec(self: &mut Expression, ctx: &mut Context) -> Result<ExecResult> {
match self {
Expression::LetExpression(expr) => expr.exec(ctx),
Expression::Command(expr) => expr.exec(ctx),
@ -94,58 +131,33 @@ impl ExecExpression for Expression {
}
}
impl ExecExpression for Command {
fn exec(&mut self, ctx: &mut Context) -> Result<Option<Command>> {
let overrides = ctx.get_overrides()?;
if let Some(stdout) = overrides.stdout { self.stdout(stdout); }
if let Some(stderr) = overrides.stderr { self.stderr(stderr); }
if let Some(stdin) = overrides.stdin { self.stdin(stdin); }
let name = self.get_program().to_str().unwrap_or("unknown").to_string();
let out = self.spawn()
.with_context(|| "Failed to spawn process ".to_string() + &name)?
.wait()
.with_context(|| "Failed to wait for process")?;
ctx.set_var(String::from("?"), Variable::I32(out.code().unwrap_or(-1)));
Ok(None)
}
}
impl ExecExpression for Option<Command> {
fn exec(&mut self, ctx: &mut Context) -> Result<Option<Command>> {
match self {
None => Ok(None),
Some(cmd) => cmd.exec(ctx)
}
}
}
impl ExecExpression for BreakExpression {
fn exec(self: &mut BreakExpression, ctx: &mut Context) -> Result<Option<Command>> {
if ctx.break_num > 0 { ctx.break_num -= 1; return Ok(None) }
fn exec(self: &mut BreakExpression, ctx: &mut Context) -> Result<ExecResult> {
if ctx.break_num > 0 { ctx.break_num -= 1; return Ok(ExecResult::default()) }
let val = self.num.get(ctx)?.to_string();
let num: u16 = if !val.is_empty() { val.parse()? } else { 1 };
ctx.break_num = if num == 0 { 1 } else { num };
Ok(None)
Ok(ExecResult::default())
}
}
impl ExecExpression for WhileExpression {
fn exec(self: &mut WhileExpression, ctx: &mut Context) -> Result<Option<Command>> {
if ctx.break_num > 0 { ctx.break_num -= 1; return Ok(None) }
let mut condition = match self.condition.exec(ctx)? {
None => bail!("Invalid while expression"),
Some(cmd) => cmd
};
fn exec(self: &mut WhileExpression, ctx: &mut Context) -> Result<ExecResult> {
if ctx.break_num > 0 { ctx.break_num -= 1; return Ok(ExecResult::default()) }
ctx.add_scope();
let mut res;
let mut res: Option<ExecResult> = None;
loop {
let condition = self.condition.exec(ctx)?;
let condition_res = condition.exec(ctx)?;
let code = ctx.get_last_exit_code().unwrap_or(1);
let code = condition_res.unwrap_or(1);
if code == 0 {
res = self.contents.exec(ctx)?
if let Some(result) = res {
result.exec(ctx)?;
}
res = Some(self.contents.exec(ctx)?);
} else {
res = condition_res;
res = None;
break;
}
if ctx.break_num > 0 {
@ -155,13 +167,13 @@ impl ExecExpression for WhileExpression {
}
ctx.pop_scope();
Ok(res)
Ok(res.unwrap_or(ExecResult::default()))
}
}
impl ExecExpression for ForExpression {
fn exec<'a>(&mut self, ctx: &mut Context) -> Result<Option<Command>> {
if ctx.break_num > 0 { ctx.break_num -= 1; return Ok(None) }
fn exec<'a>(&mut self, ctx: &mut Context) -> Result<ExecResult> {
if ctx.break_num > 0 { ctx.break_num -= 1; return Ok(ExecResult::default()) }
let arg_value = self.arg_value.get(ctx)?;
let arg_key = match &self.arg_key {
None => None,
@ -171,7 +183,7 @@ impl ExecExpression for ForExpression {
Some(res)
}
};
let mut res: Option<Command> = None;
let mut res: Option<ExecResult> = None;
let list = self.list.get(ctx)?;
fn process(i: usize, val: Variable, ctx: &mut Context, arg_key: &Option<Variable>, arg_value: &Variable) -> Result<()> {
@ -190,8 +202,10 @@ impl ExecExpression for ForExpression {
} else {
for (i, val) in arr.iter().enumerate() {
process(i, val.clone(), ctx, &arg_key, &arg_value)?;
if let Some(res) = res {
res.exec(ctx)?;
res = self.contents.exec(ctx)?;
}
res = Some(self.contents.exec(ctx)?);
ctx.pop_scope();
if ctx.break_num > 0 {
ctx.break_num -= 1;
@ -206,8 +220,10 @@ impl ExecExpression for ForExpression {
} else {
for (i, char) in str.chars().enumerate() {
process(i, Variable::String(char.to_string()), ctx, &arg_key, &arg_value)?;
if let Some(res) = res {
res.exec(ctx)?;
res = self.contents.exec(ctx)?;
}
res = Some(self.contents.exec(ctx)?);
ctx.pop_scope();
if ctx.break_num > 0 {
ctx.break_num -= 1;
@ -219,20 +235,17 @@ impl ExecExpression for ForExpression {
_ => bail!("Invalid for expression")
};
Ok(res)
Ok(res.unwrap_or(ExecResult::default()))
}
}
impl ExecExpression for IfExpression {
fn exec(self: &mut IfExpression, ctx: &mut Context) -> Result<Option<Command>> {
if ctx.break_num > 0 { return Ok(None) }
let mut condition = match self.condition.exec(ctx)? {
None => bail!("Invalid IF expression"),
Some(cmd) => cmd
};
fn exec(self: &mut IfExpression, ctx: &mut Context) -> Result<ExecResult> {
if ctx.break_num > 0 { return Ok(ExecResult::default()) }
let condition = self.condition.exec(ctx)?;
ctx.add_scope();
condition.exec(ctx)?;
let code = ctx.get_last_exit_code().unwrap_or(1);
let condition_result = condition.exec(ctx)?;
let code = condition_result.unwrap_or(1);
let res= if code == 0 {
self.contents.exec(ctx)?
} else {
@ -245,18 +258,18 @@ impl ExecExpression for IfExpression {
}
impl ExecExpression for LetExpression {
fn exec(self: &mut LetExpression, ctx: &mut Context) -> Result<Option<Command>> {
if ctx.break_num > 0 { return Ok(None) }
fn exec(self: &mut LetExpression, ctx: &mut Context) -> Result<ExecResult> {
if ctx.break_num > 0 { return Ok(ExecResult::default()) }
let key = self.key.get(ctx)?;
let val = self.value.get(ctx)?;
ctx.set_var(key.to_string(), val);
Ok(None)
Ok(ExecResult::default())
}
}
impl ExecExpression for Vec<CommandValue> {
fn exec(self: &mut Vec<CommandValue>, ctx: &mut Context) -> Result<Option<Command>> {
if ctx.break_num > 0 { return Ok(None) }
fn exec(self: &mut Vec<CommandValue>, ctx: &mut Context) -> Result<ExecResult> {
if ctx.break_num > 0 { return Ok(ExecResult::default()) }
if self.is_empty() { bail!("Command with 0 length"); }
let first = self.get_mut(0).unwrap();
let command_name = first.get(ctx)?.to_string();
@ -264,96 +277,102 @@ impl ExecExpression for Vec<CommandValue> {
for value in &mut self[1..] {
cmd.arg(value.get(ctx)?.to_string());
}
Ok(Some(cmd))
let overrides = ctx.get_overrides()?;
if let Some(stdout) = overrides.stdout { cmd.stdout(stdout); }
if let Some(stderr) = overrides.stderr { cmd.stderr(stderr); }
if let Some(stdin) = overrides.stdin { cmd.stdin(stdin); }
Ok(ExecResult {
commands: vec![cmd]
})
}
}
impl ExecExpression for RedirectTargetExpression {
fn exec(self: &mut RedirectTargetExpression, ctx: &mut Context) -> Result<Option<Command>> {
if ctx.break_num > 0 { return Ok(None) }
fn exec(self: &mut RedirectTargetExpression, ctx: &mut Context) -> Result<ExecResult> {
if ctx.break_num > 0 { return Ok(ExecResult::default()) }
let (reader, writer) = os_pipe::pipe()?;
let mut src = self.source.exec(ctx)?.unwrap();
let mut target = self.target.exec(ctx)?.unwrap();
target.stdin(reader);
ctx.add_scope();
ctx.scopes.last_mut().unwrap().stdout_override = Some(writer);
src.exec(ctx)?;
ctx.pop_scope();
Ok(Some(target))
ctx.add_scope();
ctx.scopes.last_mut().unwrap().stdout_override = Some(WriterOverride::Pipe(writer));
let mut src = self.source.exec(ctx)?;
ctx.pop_scope();
ctx.add_scope();
ctx.scopes.last_mut().unwrap().stdin_override = Some(ReaderOverride::Pipe(reader));
let target = self.target.exec(ctx)?;
ctx.pop_scope();
src.merge(target);
Ok(src)
}
}
impl ExecExpression for FileTargetExpression {
fn exec(self: &mut FileTargetExpression, ctx: &mut Context) -> Result<Option<Command>> {
if ctx.break_num > 0 { return Ok(None) }
fn exec(self: &mut FileTargetExpression, ctx: &mut Context) -> Result<ExecResult> {
if ctx.break_num > 0 { return Ok(ExecResult::default()) }
let src = &mut self.source;
let target = self.target.get(ctx)?;
ctx.add_scope();
let file = File::create(target.to_string())?;
ctx.scopes.last_mut().unwrap().stdout_override = Some(WriterOverride::File(file));
let src = match src {
Some(expr) => expr.exec(ctx)?,
None => {
todo!("Redirect without target file");
bail!("Redirect without target file");
}
};
let command = match src {
Some(mut cmd) => {
let file = File::create(target.to_string())?;
cmd.stdout(file);
cmd
},
None => { bail!("Invalid command provided for file target"); }
};
Ok(Some(command))
ctx.pop_scope();
Ok(src)
}
}
impl ExecExpression for FileSourceExpression {
fn exec(self: &mut FileSourceExpression, ctx: &mut Context) -> Result<Option<Command>> {
if ctx.break_num > 0 { return Ok(None) }
fn exec(self: &mut FileSourceExpression, ctx: &mut Context) -> Result<ExecResult> {
if ctx.break_num > 0 { return Ok(ExecResult::default()) }
let source = self.source.get(ctx)?.to_string();
let source = File::open(source).with_context(|| "Couldn't open file to read")?;
let target = &mut self.target;
ctx.add_scope();
ctx.scopes.last_mut().unwrap().stdin_override = Some(ReaderOverride::File(source));
let target = match target {
Some(expr) => expr.exec(ctx)?,
None => {
Some(Command::new("less"))
vec![CommandValue::Value(Value::Literal(String::from("less")))].exec(ctx)?
}
};
let mut command = match target {
None => { bail!("Invalid command") },
Some(cmd) => cmd
};
let source = File::open(source).with_context(|| "Couldn't open file to read")?;
command.stdin(source);
ctx.pop_scope();
Ok(Some(command))
Ok(target)
}
}
impl ExecExpression for Vec<Expression> {
fn exec(self: &mut Vec<Expression>, ctx: &mut Context) -> Result<Option<Command>> {
if ctx.break_num > 0 { return Ok(None) }
let mut last = None;
fn exec(self: &mut Vec<Expression>, ctx: &mut Context) -> Result<ExecResult> {
if ctx.break_num > 0 { return Ok(ExecResult::default()) }
let mut last: Option<ExecResult> = None;
for expr in self {
if let Some(last) = last {
last.exec(ctx)?;
last = expr.exec(ctx)?;
if ctx.break_num > 0 { return Ok(last) }
}
Ok(last)
last = Some(expr.exec(ctx)?);
if ctx.break_num > 0 { return Ok(last.unwrap()) }
}
Ok(last.unwrap_or(ExecResult::default()))
}
}
impl ExecExpression for OrExpression {
fn exec(self: &mut OrExpression, ctx: &mut Context) -> Result<Option<Command>> {
if ctx.break_num > 0 { return Ok(None) }
let mut first = match self.first.exec(ctx)? {
None => bail!("Invalid OR expression"),
Some(cmd) => cmd
};
first.exec(ctx)?;
let code = ctx.get_last_exit_code().unwrap_or(1);
fn exec(self: &mut OrExpression, ctx: &mut Context) -> Result<ExecResult> {
if ctx.break_num > 0 { return Ok(ExecResult::default()) }
let first = self.first.exec(ctx)?;
let code = first.exec(ctx)?;
let code = code.unwrap_or(1);
if code == 0 {
Ok(Some(first))
Ok(ExecResult::default())
} else {
self.second.exec(ctx)
}
@ -361,25 +380,22 @@ impl ExecExpression for OrExpression {
}
impl ExecExpression for AndExpression {
fn exec(self: &mut AndExpression, ctx: &mut Context) -> Result<Option<Command>> {
if ctx.break_num > 0 { return Ok(None) }
let mut first = match self.first.exec(ctx)? {
None => bail!("Invalid AND expression"),
Some(cmd) => cmd
};
first.exec(ctx)?;
let code = ctx.get_last_exit_code().unwrap_or(1);
fn exec(self: &mut AndExpression, ctx: &mut Context) -> Result<ExecResult> {
if ctx.break_num > 0 { return Ok(ExecResult::default()) }
let first = self.first.exec(ctx)?;
let code = first.exec(ctx)?;
let code = code.unwrap_or(1);
if code == 0 {
self.second.exec(ctx)
} else {
Ok(Some(first))
Ok(ExecResult::default())
}
}
}
pub fn exec_tree(tree: Vec<Expression>, ctx: &mut Context) -> Result<()> {
for mut expression in tree {
let mut cmd = expression.exec(ctx)?;
let cmd = expression.exec(ctx)?;
cmd.exec(ctx)?;
if ctx.break_num > 0 { bail!("Too many break statements") }
}

View file

@ -1,5 +1,9 @@
use std::collections::HashMap;
use std::fmt::{Debug, Display, Formatter};
use std::fs::File;
use std::io::{Read, Write};
use std::process::Stdio;
use std::sync::Arc;
use anyhow::{bail, Result};
use os_pipe::{PipeReader, PipeWriter};
use crate::parser::ast::FunctionDefinitionExpression;
@ -172,10 +176,59 @@ pub enum AnyFunction<'a> {
UserDefined(&'a mut FunctionDefinitionExpression)
}
trait TryClone<T> {
fn try_clone(&self) -> Result<T>;
}
#[derive(Debug)]
pub enum WriterOverride {
Pipe(PipeWriter),
File(File)
}
#[derive(Debug)]
pub enum ReaderOverride {
Pipe(PipeReader),
File(File)
}
impl TryClone<WriterOverride> for WriterOverride {
fn try_clone(&self) -> Result<WriterOverride> {
Ok(match self {
WriterOverride::Pipe(pipe) => WriterOverride::Pipe(pipe.try_clone()?),
WriterOverride::File(file) => WriterOverride::File(file.try_clone()?)
})
}
}
impl TryClone<ReaderOverride> for ReaderOverride {
fn try_clone(&self) -> Result<ReaderOverride> {
Ok(match self {
ReaderOverride::Pipe(pipe) => ReaderOverride::Pipe(pipe.try_clone()?),
ReaderOverride::File(file) => ReaderOverride::File(file.try_clone()?)
})
}
}
impl From<WriterOverride> for Stdio {
fn from(value: WriterOverride) -> Self {
match value {
WriterOverride::Pipe(pipe) => pipe.into(),
WriterOverride::File(file) => file.into()
}
}
}
impl From<ReaderOverride> for Stdio {
fn from(value: ReaderOverride) -> Self {
match value {
ReaderOverride::Pipe(pipe) => pipe.into(),
ReaderOverride::File(file) => file.into()
}
}
}
pub struct Overrides {
pub stdin: Option<PipeReader>,
pub stdout: Option<PipeWriter>,
pub stderr: Option<PipeWriter>
pub stdin: Option<ReaderOverride>,
pub stdout: Option<WriterOverride>,
pub stderr: Option<WriterOverride>
}
#[derive(Debug)]
@ -186,9 +239,9 @@ pub struct Scope {
pub func: HashMap<String, FunctionDefinitionExpression>,
/// list of file descriptors, to be closed when the scope is left
pub fd: Vec<usize>,
pub stdin_override: Option<PipeReader>,
pub stdout_override: Option<PipeWriter>,
pub stderr_override: Option<PipeWriter>
pub stdin_override: Option<ReaderOverride>,
pub stdout_override: Option<WriterOverride>,
pub stderr_override: Option<WriterOverride>
}
#[derive(Debug)]