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feat: improve bash-like command parsing

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binekrasik
2026-05-19 18:22:43 +02:00
parent b5f53473ed
commit 4a484dd546
8 changed files with 399 additions and 105 deletions
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21
src/shell/wush/ShellEnvironment.ts Normal file
View File

@@ -0,0 +1,21 @@
/**
* Wush environment manager
* Manages environment variables, aliases etc.
*/
export class ShellEnvironment {
private variables: Record<string, string> = {}
SetVariable(name: string, value: string | null): void {
// remove the variable if value is null
if (value === null) {
delete this.variables[name]
return
}
this.variables[name] = value
}
GetVariable(name: string): string | undefined {
return this.variables[name]
}
}

361
src/shell/wush/Wush.ts
View File

@@ -22,6 +22,8 @@ import { Cat } from '../../program/Cat'
import { Echo } from '../../program/Echo'
import { Mkdir } from '../../program/Mkdir'
import { Cd } from '../../program/Cd'
import { Printf } from '../../program/Printf'
import { Pwd } from '../../program/Pwd'
// import { Pwd } from '../program/Pwd'
// import { Cd } from '../program/Cd'
@@ -83,8 +85,9 @@ export class Wush extends Shell {
this.programs['cat'] = new Cat()
this.programs['echo'] = new Echo()
this.programs['mkdir'] = new Mkdir()
// this.programs['pwd'] = new Pwd()
this.programs['pwd'] = new Pwd()
this.programs['cd'] = new Cd(this)
this.programs['printf'] = new Printf()
this.stdout.on(data => this.WriteEscapedString(data))
this.Prompt()
@@ -102,28 +105,32 @@ export class Wush extends Shell {
delete this.programs[name]
}
ExecuteProgram(name: string, args: string[]) {
this.programs[name].Exec(this.stdin, this.stdout, this.workingDirectory, args)
.then(code => {
this.execExitCode = code != -1 ? code : -2
})
.catch((e) => {
this.WriteEscapedString(`wush: command ${name} exited with the following exception\n`)
this.WriteEscapedString(` | ${String(e)}\n`)
})
.finally(() => {
// check if the exec actually exited with an exit code
// and if not, set it to -2 to indicate that it didn't exit with a valid code
if (this.execExitCode === -1)
this.execExitCode = -2
async ExecuteProgram(name: string, args: string[]): Promise<void> {
return new Promise<void>(resolve => {
this.programs[name].Exec(this.stdin, this.stdout, this.workingDirectory, args)
.then(code => {
this.execExitCode = code != -1 ? code : -2
resolve()
})
.catch((e) => {
this.WriteEscapedString(`wush: command ${name} exited with the following exception\n`)
this.WriteEscapedString(` | ${String(e)}\n`)
resolve()
})
.finally(() => {
// check if the exec actually exited with an exit code
// and if not, set it to -2 to indicate that it didn't exit with a valid code
if (this.execExitCode === -1)
this.execExitCode = -2
// this.terminal.Write(`The program exited with exit code ${this.execExitCode}.`)
this.Prompt()
})
// this.terminal.Write(`The program exited with exit code ${this.execExitCode}.`)
resolve()
})
})
}
Prompt() {
this.terminal.Write(`boykisser in ${this.workingDirectory.GetPath()} -> `)
this.terminal.Write(`user in ${this.workingDirectory.GetPath()} -> `)
}
/**
@@ -175,79 +182,267 @@ export class Wush extends Shell {
this.bufferPos = 0
}
ExecuteBuffer() {
// parse the buffer
const state: {
inString: boolean
inHardString: boolean
inAndOperator: boolean
} = {
inString: false,
inHardString: false,
inAndOperator: false,
}
const commands: {
async ExecuteBuffer() {
type OperatorToken = '&&' | '||' | '|' | ';'
type Token = { type: 'word'; value: string } | { type: 'operator'; value: OperatorToken }
type ParsedCommand = {
args: string[]
stdin: null | SimpleStream<string>
stdout: null | SimpleStream<string>
}[] = []
}
type ParsedPipeline = { commands: ParsedCommand[] }
type ParsedListItem = { pipeline: ParsedPipeline; operator: '&&' | '||' | ';' | null }
const textBuf =
this.buffer
.join('')
.split('')
const tokenize = (text: string): { tokens: Token[]; error: string | null } => {
const tokens: Token[] = []
let current = ''
let wordStarted = false
let inSingleQuote = false
let inDoubleQuote = false
let escapeNext = false
textBuf.forEach((char, i) => {
// spacing
if (char === ' ' && !(state.inString || state.inHardString )) {
if (state.args[state.args.length - 1] !== '')
state.args.push("")
// string ("") handling
} else if (char === '"' && !state.inHardString) {
state.inString = !state.inString
// hard string ('') handling
} else if (char === "'" && !state.inString) {
state.inHardString = !state.inHardString
// && operator
} else if (char === '&' || char === '|' && !(state.inString || state.inHardString )) {
if (state.inAndOperator) {
if (state.args[state.args.length - 1] === '')
state.args[state.args.length - 1] = `${char}${char}`
else state.args.push(`${char}${char}`)
const pushWord = () => {
if (!wordStarted)
return
state.args.push("")
state.inAndOperator = false
} else if (this.buffer[i + 1] !== char) {
state.args[state.args.length - 1] += char
} else state.inAndOperator = true
// adding the char to the current argument
} else {
state.args[state.args.length - 1] += char
}
})
this.FlushBuffer()
console.log(`Executing ${state.args[0]} with args '${state.args}'`)
this.execExitCode = -1
if (this.programs[state.args[0]] instanceof Program) {
this.ExecuteProgram(state.args[0], state.args)
} else {
this.execExitCode = 0
// don't print anything if there are no arguments
if (state.args[0].length !== 0) {
this.terminal.Write(`wush: unknown command: ${state.args[0]}.`)
this.terminal.MoveCursor(0, 1, { x: true, y: false })
this.execExitCode = 127
tokens.push({ type: 'word', value: current })
current = ''
wordStarted = false
}
this.Prompt()
for (let i = 0; i < text.length; i++) {
const char = text[i]
if (escapeNext) {
current += char
escapeNext = false
wordStarted = true
continue
}
if (inSingleQuote) {
if (char === "'") {
inSingleQuote = false
wordStarted = true
} else {
current += char
wordStarted = true
}
continue
}
if (inDoubleQuote) {
if (char === '"') {
inDoubleQuote = false
wordStarted = true
} else if (char === '\\') {
if (i + 1 >= text.length)
return { tokens: [], error: 'unterminated escape sequence' }
current += text[i + 1]
i++
wordStarted = true
} else {
current += char
wordStarted = true
}
continue
}
if (char === '\\') {
escapeNext = true
wordStarted = true
continue
}
if (char === "'") {
inSingleQuote = true
wordStarted = true
continue
}
if (char === '"') {
inDoubleQuote = true
wordStarted = true
continue
}
if (char === ' ' || char === '\t') {
pushWord()
continue
}
if (char === '#') {
if (!wordStarted)
break
current += char
wordStarted = true
continue
}
if (char === ';') {
pushWord()
tokens.push({ type: 'operator', value: ';' })
continue
}
if (char === '|') {
pushWord()
if (text[i + 1] === '|') {
tokens.push({ type: 'operator', value: '||' })
i++
} else {
tokens.push({ type: 'operator', value: '|' })
}
continue
}
if (char === '&') {
if (text[i + 1] === '&') {
pushWord()
tokens.push({ type: 'operator', value: '&&' })
i++
} else {
current += char
wordStarted = true
}
continue
}
current += char
wordStarted = true
}
if (escapeNext)
return { tokens: [], error: 'unterminated escape sequence' }
if (inSingleQuote)
return { tokens: [], error: 'unterminated single quote' }
if (inDoubleQuote)
return { tokens: [], error: 'unterminated double quote' }
pushWord()
return { tokens, error: null }
}
const parseTokens = (tokens: Token[]): { list: ParsedListItem[]; error: string | null } => {
const list: ParsedListItem[] = []
let currentArgs: string[] = []
let currentPipeline: ParsedCommand[] = []
let expectCommand = false
const pushCommand = () => {
if (currentArgs.length === 0)
return false
currentPipeline.push({
args: currentArgs,
stdin: null,
stdout: null,
})
currentArgs = []
return true
}
const pushPipeline = (operator: '&&' | '||' | ';' | null) => {
if (currentPipeline.length === 0)
return false
list.push({ pipeline: { commands: currentPipeline }, operator })
currentPipeline = []
return true
}
for (const token of tokens) {
if (token.type === 'word') {
currentArgs.push(token.value)
expectCommand = false
continue
}
if (token.value === '|') {
if (!pushCommand())
return { list: [], error: 'unexpected "|" operator' }
expectCommand = true
continue
}
if (!pushCommand() || !pushPipeline(token.value))
return { list: [], error: `unexpected "${token.value}" operator` }
expectCommand = true
}
if (expectCommand)
return { list: [], error: 'unexpected end of input' }
if (currentArgs.length > 0)
pushCommand()
if (currentPipeline.length > 0)
pushPipeline(null)
return { list, error: null }
}
const line = this.buffer.join('')
this.FlushBuffer()
const { tokens, error } = tokenize(line)
if (error) {
this.terminal.Write(`wush: error: ${error}`)
this.terminal.MoveCursor(0, 1, { x: true, y: false })
this.Prompt()
return
}
const { list, error: parseError } = parseTokens(tokens)
if (parseError) {
this.terminal.Write(`wush: error: ${parseError}`)
this.terminal.MoveCursor(0, 1, { x: true, y: false })
this.Prompt()
return
}
if (list.length === 0) {
this.Prompt()
return
}
if (list.some(item => item.pipeline.commands.length > 1)) {
this.terminal.Write(`wush: error: pipes are not supported yet`)
this.terminal.MoveCursor(0, 1, { x: true, y: false })
this.Prompt()
return
}
for (const item of list) {
const command = item.pipeline.commands[0]
this.execExitCode = -1
if (this.programs[command.args[0]] instanceof Program) {
await this.ExecuteProgram(command.args[0], command.args)
} else {
this.execExitCode = 0
// don't print anything if there are no arguments
if (command.args[0].length !== 0) {
this.terminal.Write(`wush: error: unknown command: ${command.args[0]}.`)
this.terminal.MoveCursor(0, 1, { x: true, y: false })
this.execExitCode = 127
}
}
}
this.Prompt()
}
ProcessSimpleControlCode(code: string): boolean {