began work on implementing those weird variable string op things

This commit is contained in:
2025-05-12 01:04:53 -04:00
parent cc8d384704
commit 2666670939
2 changed files with 289 additions and 25 deletions

View File

@@ -1,6 +1,9 @@
use std::collections::HashSet;
use std::str::FromStr;
use crate::state::{read_vars, write_meta, LogTab};
use glob::Pattern;
use crate::state::{read_vars, write_meta, write_vars, LogTab};
use crate::procio::{IoBuf, IoFrame, IoMode};
use crate::prelude::*;
use crate::parse::{Redir, RedirType};
@@ -122,7 +125,7 @@ impl Expander {
}
'{' if var_name.is_empty() => in_brace = true,
'}' if in_brace => {
let var_val = read_vars(|v| v.get_var(&var_name));
let var_val = perform_param_expansion(&var_name)?;
result.push_str(&var_val);
var_name.clear();
break
@@ -321,6 +324,256 @@ pub fn unescape_str(raw: &str) -> String {
result
}
pub enum ParamExp {
Len, // #var_name
DefaultUnsetOrNull(String), // :-
DefaultUnset(String), // -
SetDefaultUnsetOrNull(String), // :=
SetDefaultUnset(String), // =
AltSetNotNull(String), // :+
AltNotNull(String), // +
ErrUnsetOrNull(String), // :?
ErrUnset(String), // ?
Substr(usize), // :pos
SubstrLen(usize,usize), // :pos:len
RemShortestPrefix(String), // #pattern
RemLongestPrefix(String), // ##pattern
RemShortestSuffix(String), // %pattern
RemLongestSuffix(String), // %%pattern
ReplaceFirstMatch(String,String), // /search/replace
ReplaceAllMatches(String,String), // //search/replace
ReplacePrefix(String,String), // #search/replace
ReplaceSuffix(String,String), // %search/replace
VarNamesWithSuffix(String), // !prefix@ || !prefix*
ExpandInnerVar(String), // !var
}
impl FromStr for ParamExp {
type Err = ShErr;
fn from_str(s: &str) -> Result<Self, Self::Err> {
use ParamExp::*;
let parse_err = || Err(ShErr::Simple {
kind: ShErrKind::SyntaxErr,
msg: "Invalid parameter expansion".into(),
notes: vec![],
});
// Handle indirect var expansion: ${!var}
if let Some(var) = s.strip_prefix('!') {
if var.ends_with('*') || var.ends_with('@') {
return Ok(VarNamesWithSuffix(var.to_string()));
}
return Ok(ExpandInnerVar(var.to_string()));
}
// Pattern removals
if let Some(rest) = s.strip_prefix("##") {
return Ok(RemLongestPrefix(rest.to_string()));
} else if let Some(rest) = s.strip_prefix('#') {
return Ok(RemShortestPrefix(rest.to_string()));
}
if let Some(rest) = s.strip_prefix("%%") {
return Ok(RemLongestSuffix(rest.to_string()));
} else if let Some(rest) = s.strip_prefix('%') {
return Ok(RemShortestSuffix(rest.to_string()));
}
// Replacements
if let Some(rest) = s.strip_prefix("//") {
let mut parts = rest.splitn(2, '/');
let pattern = parts.next().unwrap_or("");
let repl = parts.next().unwrap_or("");
return Ok(ReplaceAllMatches(pattern.to_string(), repl.to_string()));
}
if let Some(rest) = s.strip_prefix('/') {
let mut parts = rest.splitn(2, '/');
let pattern = parts.next().unwrap_or("");
let repl = parts.next().unwrap_or("");
return Ok(ReplaceFirstMatch(pattern.to_string(), repl.to_string()));
}
// Fallback / assignment / alt
if let Some(rest) = s.strip_prefix(":-") {
return Ok(DefaultUnsetOrNull(rest.to_string()));
} else if let Some(rest) = s.strip_prefix('-') {
return Ok(DefaultUnset(rest.to_string()));
} else if let Some(rest) = s.strip_prefix(":+") {
return Ok(AltSetNotNull(rest.to_string()));
} else if let Some(rest) = s.strip_prefix('+') {
return Ok(AltNotNull(rest.to_string()));
} else if let Some(rest) = s.strip_prefix(":=") {
return Ok(SetDefaultUnsetOrNull(rest.to_string()));
} else if let Some(rest) = s.strip_prefix('=') {
return Ok(SetDefaultUnset(rest.to_string()));
} else if let Some(rest) = s.strip_prefix(":?") {
return Ok(ErrUnsetOrNull(rest.to_string()));
} else if let Some(rest) = s.strip_prefix('?') {
return Ok(ErrUnset(rest.to_string()));
}
// Substring
if let Some((pos, len)) = parse_pos_len(s) {
return Ok(match len {
Some(l) => SubstrLen(pos, l),
None => Substr(pos),
});
}
parse_err()
}
}
pub fn parse_pos_len(s: &str) -> Option<(usize, Option<usize>)> {
let raw = s.strip_prefix(':')?;
if let Some((start,len)) = raw.split_once(':') {
Some((
start.parse::<usize>().ok()?,
len.parse::<usize>().ok(),
))
} else {
Some((
raw.parse::<usize>().ok()?,
None,
))
}
}
pub fn perform_param_expansion(raw: &str) -> ShResult<String> {
let vars = read_vars(|v| v.clone());
let mut chars = raw.chars();
let mut var_name = String::new();
let mut rest = String::new();
if raw.starts_with('#') {
return Ok(vars.get_var(raw.strip_prefix('#').unwrap()).len().to_string())
}
while let Some(ch) = chars.next() {
match ch {
'!' |
'#' |
'%' |
':' |
'-' |
'+' |
'=' |
'?' => {
rest = chars.collect();
break
}
_ => var_name.push(ch)
}
}
if let Ok(expansion) = rest.parse::<ParamExp>() {
match expansion {
ParamExp::Len => unreachable!(),
ParamExp::DefaultUnsetOrNull(default) => {
if !vars.var_exists(&var_name) || vars.get_var(&var_name).is_empty() {
Ok(default)
} else {
Ok(vars.get_var(&var_name))
}
}
ParamExp::DefaultUnset(default) => {
if !vars.var_exists(&var_name) {
Ok(default)
} else {
Ok(vars.get_var(&var_name))
}
}
ParamExp::SetDefaultUnsetOrNull(default) => {
if !vars.var_exists(&var_name) || vars.get_var(&var_name).is_empty() {
write_vars(|v| v.set_var(&var_name, &default, false));
Ok(default)
} else {
Ok(vars.get_var(&var_name))
}
}
ParamExp::SetDefaultUnset(default) => {
if !vars.var_exists(&var_name) {
write_vars(|v| v.set_var(&var_name, &default, false));
Ok(default)
} else {
Ok(vars.get_var(&var_name))
}
}
ParamExp::AltSetNotNull(alt) => {
if vars.var_exists(&var_name) && !vars.get_var(&var_name).is_empty() {
Ok(alt)
} else {
Ok("".into())
}
}
ParamExp::AltNotNull(alt) => {
if vars.var_exists(&var_name) {
Ok(alt)
} else {
Ok("".into())
}
}
ParamExp::ErrUnsetOrNull(err) => {
if !vars.var_exists(&var_name) || vars.get_var(&var_name).is_empty() {
Err(
ShErr::Simple { kind: ShErrKind::ExecFail, msg: err, notes: vec![] }
)
} else {
Ok(vars.get_var(&var_name))
}
}
ParamExp::ErrUnset(err) => {
if !vars.var_exists(&var_name) {
Err(
ShErr::Simple { kind: ShErrKind::ExecFail, msg: err, notes: vec![] }
)
} else {
Ok(vars.get_var(&var_name))
}
}
ParamExp::Substr(pos) => {
let value = vars.get_var(&var_name);
if let Some(substr) = value.get(pos..) {
Ok(substr.to_string())
} else {
Ok(value)
}
}
ParamExp::SubstrLen(pos, len) => {
let value = vars.get_var(&var_name);
let end = pos.saturating_add(len);
if let Some(substr) = value.get(pos..end) {
Ok(substr.to_string())
} else {
Ok(value)
}
}
ParamExp::RemShortestPrefix(prefix) => {
let value = vars.get_var(&var_name);
let pattern = Pattern::new(&prefix).unwrap();
for i in 0..=value.len() {
let sliced = &value[..i];
if pattern.matches(sliced) {
return Ok(value[i..].to_string())
}
}
Ok(value)
}
ParamExp::RemLongestPrefix(prefix) => todo!(),
ParamExp::RemShortestSuffix(suffix) => todo!(),
ParamExp::RemLongestSuffix(suffix) => todo!(),
ParamExp::ReplaceFirstMatch(search, replace) => todo!(),
ParamExp::ReplaceAllMatches(search, replace) => todo!(),
ParamExp::ReplacePrefix(search, replace) => todo!(),
ParamExp::ReplaceSuffix(search, replace) => todo!(),
ParamExp::VarNamesWithSuffix(suffix) => todo!(),
ParamExp::ExpandInnerVar(var_name) => todo!(),
}
} else {
Ok(vars.get_var(&var_name))
}
}
#[derive(Debug)]
pub enum PromptTk {
AsciiOct(i32),

View File

@@ -2,7 +2,7 @@ use std::{collections::{HashMap, VecDeque}, ops::Deref, sync::{LazyLock, RwLock,
use nix::unistd::{gethostname, getppid, User};
use crate::{exec_input, jobs::JobTab, libsh::{error::{ShErr, ShErrKind, ShResult}, utils::VecDequeExt}, parse::{lex::get_char, ConjunctNode, NdRule, Node, ParsedSrc}, prelude::*, shopt::ShOpts};
use crate::{exec_input, jobs::JobTab, libsh::{error::{ShErr, ShErrKind, ShResult}, utils::VecDequeExt}, parse::{ConjunctNode, NdRule, Node, ParsedSrc}, prelude::*, shopt::ShOpts};
pub static JOB_TABLE: LazyLock<RwLock<JobTab>> = LazyLock::new(|| RwLock::new(JobTab::new()));
@@ -118,7 +118,7 @@ impl Deref for Var {
#[derive(Default,Clone,Debug)]
pub struct VarTab {
vars: HashMap<String,Var>,
params: HashMap<char,String>,
params: HashMap<String,String>,
sh_argv: VecDeque<String>, // Using a VecDeque makes the implementation of `shift` straightforward
}
@@ -131,13 +131,13 @@ impl VarTab {
var_tab.init_sh_argv();
var_tab
}
fn init_params() -> HashMap<char, String> {
fn init_params() -> HashMap<String, String> {
let mut params = HashMap::new();
params.insert('?', "0".into()); // Last command exit status
params.insert('#', "0".into()); // Number of positional parameters
params.insert('0', std::env::current_exe().unwrap().to_str().unwrap().to_string()); // Name of the shell
params.insert('$', Pid::this().to_string()); // PID of the shell
params.insert('!', "".into()); // PID of the last background job (if any)
params.insert("?".into(), "0".into()); // Last command exit status
params.insert("#".into(), "0".into()); // Number of positional parameters
params.insert("0".into(), std::env::current_exe().unwrap().to_str().unwrap().to_string()); // Name of the shell
params.insert("$".into(), Pid::this().to_string()); // PID of the shell
params.insert("!".into(), "".into()); // PID of the last background job (if any)
params
}
fn init_env() {
@@ -214,8 +214,8 @@ impl VarTab {
self.bpush_arg(env::current_exe().unwrap().to_str().unwrap().to_string());
}
fn update_arg_params(&mut self) {
self.set_param('@', &self.sh_argv.clone().to_vec()[1..].join(" "));
self.set_param('#', &(self.sh_argv.len() - 1).to_string());
self.set_param("@", &self.sh_argv.clone().to_vec()[1..].join(" "));
self.set_param("#", &(self.sh_argv.len() - 1).to_string());
}
/// Push an arg to the front of the arg deque
pub fn fpush_arg(&mut self, arg: String) {
@@ -245,10 +245,10 @@ impl VarTab {
pub fn vars_mut(&mut self) -> &mut HashMap<String,Var> {
&mut self.vars
}
pub fn params(&self) -> &HashMap<char,String> {
pub fn params(&self) -> &HashMap<String,String> {
&self.params
}
pub fn params_mut(&mut self) -> &mut HashMap<char,String> {
pub fn params_mut(&mut self) -> &mut HashMap<String,String> {
&mut self.params
}
pub fn export_var(&mut self, var_name: &str) {
@@ -258,8 +258,9 @@ impl VarTab {
}
}
pub fn get_var(&self, var: &str) -> String {
if var.chars().count() == 1 {
let param = self.get_param(get_char(var, 0).unwrap());
if var.chars().count() == 1 ||
var.parse::<usize>().is_ok() {
let param = self.get_param(var);
if !param.is_empty() {
return param
}
@@ -285,21 +286,31 @@ impl VarTab {
self.vars.insert(var_name.to_string(), var);
}
}
pub fn set_param(&mut self, param: char, val: &str) {
self.params.insert(param,val.to_string());
pub fn var_exists(&self, var_name: &str) -> bool {
if var_name.parse::<usize>().is_ok() {
return self.params.contains_key(var_name);
}
self.vars.contains_key(var_name) ||
(
var_name.len() == 1 &&
self.params.contains_key(var_name)
)
}
pub fn get_param(&self, param: char) -> String {
if param.is_ascii_digit() {
pub fn set_param(&mut self, param: &str, val: &str) {
self.params.insert(param.to_string(),val.to_string());
}
pub fn get_param(&self, param: &str) -> String {
if param.parse::<usize>().is_ok() {
let argv_idx = param
.to_string()
.parse::<usize>()
.unwrap();
let arg = self.sh_argv.get(argv_idx).map(|s| s.to_string()).unwrap_or_default();
arg
} else if param == '?' {
self.params.get(&param).map(|s| s.to_string()).unwrap_or("0".into())
} else if param == "?" {
self.params.get(param).map(|s| s.to_string()).unwrap_or("0".into())
} else {
self.params.get(&param).map(|s| s.to_string()).unwrap_or_default()
self.params.get(param).map(|s| s.to_string()).unwrap_or_default()
}
}
}
@@ -389,11 +400,11 @@ pub fn get_shopt(path: &str) -> String {
}
pub fn get_status() -> i32 {
read_vars(|v| v.get_param('?')).parse::<i32>().unwrap()
read_vars(|v| v.get_param("?")).parse::<i32>().unwrap()
}
#[track_caller]
pub fn set_status(code: i32) {
write_vars(|v| v.set_param('?', &code.to_string()))
write_vars(|v| v.set_param("?", &code.to_string()))
}
/// Save the current state of the logic and variable table, and the working directory path