use std::cell::Cell; use std::collections::HashMap; use std::error::Error as StdError; use std::fs::File; use std::io::{BufRead, BufReader, Cursor, Error as IoError, Lines}; use std::iter::Peekable; use std::path::Path; use eyre::{bail, eyre, Context, Result}; use lazy_static::lazy_static; use regex::Regex; use crate::args::Args; use super::command_line::CommandLine; #[cfg(feature = "full")] use super::conditional::{Line as ConditionalLine, State as ConditionalState}; use super::inference_rules::InferenceRule; use super::r#macro::{Set as MacroSet, Source as MacroSource}; use super::target::Target; use super::token::{tokenize, Token, TokenString}; enum LineType { Rule, Macro, Unknown, } impl LineType { fn of(line_tokens: &TokenString) -> Self { #[cfg(feature = "full")] if line_tokens.starts_with("define ") { return Self::Macro; } for token in line_tokens.tokens() { if let Token::Text(text) = token { let colon_idx = text.find(':'); #[cfg(not(feature = "full"))] let equals_idx = text.find('='); #[cfg(feature = "full")] let equals_idx = ["=", ":=", "::=", "?=", "+="] .iter() .filter_map(|p| text.find(p)) .min(); match (colon_idx, equals_idx) { (Some(_), None) => { return Self::Rule; } (Some(c), Some(e)) if c < e => { return Self::Rule; } (None, Some(_)) => { return Self::Macro; } (Some(c), Some(e)) if e <= c => { return Self::Macro; } _ => {} } } } Self::Unknown } } fn inference_match<'a>( targets: &[&'a str], prerequisites: &[String], ) -> Option> { lazy_static! { static ref INFERENCE_RULE: Regex = Regex::new(r"^(?P(\.[^/.]+)?)(?P\.[^/.]+)$").unwrap(); static ref SPECIAL_TARGET: Regex = Regex::new(r"^\.[A-Z]+$").unwrap(); } let inference_match = INFERENCE_RULE.captures(targets[0]); let special_target_match = SPECIAL_TARGET.captures(targets[0]); let inference_rule = targets.len() == 1 && prerequisites.is_empty() && inference_match.is_some() && special_target_match.is_none(); if inference_rule { inference_match } else { None } } struct LineNumbers(Inner, usize) where E: StdError + Send + Sync + 'static, Inner: Iterator>; impl LineNumbers where E: StdError + Send + Sync + 'static, Inner: Iterator>, { fn new(inner: Inner) -> Self { Self(inner, 0) } } impl Iterator for LineNumbers where E: StdError + Send + Sync + 'static, Inner: Iterator>, { type Item = (usize, Result); fn next(&mut self) -> Option { self.0.next().map(|x| { self.1 = self.1.saturating_add(1); ( self.1, x.with_context(|| format!("failed to read line {} of makefile", self.1)), ) }) } } trait IteratorExt: Iterator> { fn line_numbered(self) -> LineNumbers where Self: Sized, { LineNumbers::new(self) } } impl>> IteratorExt for I { } pub struct MakefileReader<'a, 'parent, R: BufRead> { pub inference_rules: Vec, pub macros: MacroSet<'parent, 'static>, pub targets: HashMap, pub first_non_special_target: Option, args: &'a Args, lines_iter: Peekable>>, #[cfg(feature = "full")] conditional_stack: Vec, } impl<'a, 'parent> MakefileReader<'a, 'parent, BufReader> { pub fn read_file( args: &'a Args, macros: MacroSet<'parent, 'static>, path: impl AsRef, ) -> Result { let file = File::open(path); // TODO handle errors let file = file.context("couldn't open makefile!")?; let file_reader = BufReader::new(file); Self::read(args, macros, file_reader) } } impl<'a, 'parent, R: BufRead> MakefileReader<'a, 'parent, R> { pub fn read(args: &'a Args, macros: MacroSet<'parent, 'static>, source: R) -> Result { let mut reader = Self { inference_rules: Vec::new(), macros, targets: HashMap::new(), first_non_special_target: None, args, lines_iter: source.lines().line_numbered().peekable(), #[cfg(feature = "full")] conditional_stack: Vec::new(), }; reader.read_all()?; Ok(reader) } fn read_all(&mut self) -> Result<()> { while let Some((line_number, line)) = self.next_line(" ") { let line = line?; // handle include lines if let Some(line) = line.strip_prefix("include ") { // remove extra leading space let line = line.trim_start(); let line = self.expand_macros(&tokenize(line)?)?; let fields = line.split_whitespace(); // POSIX says we only have to handle a single filename, but GNU make // handles arbitrarily many filenames, and it's not like that's more work for field in fields { let child_macros = self.macros.with_overlay(); let child = MakefileReader::read_file(self.args, child_macros, field) .with_context(|| format!("while including {}", field))? .finish(); self.extend(child); } continue; } if line.trim().is_empty() { // handle blank lines continue; } // unfortunately, rules vs macros can't be determined until after // macro tokenizing. so that's suboptimal. // TODO errors let line_tokens: TokenString = line .parse() .with_context(|| format!("failed to parse line {}", line_number))?; let line_type = LineType::of(&line_tokens); // before we actually test it, see if it's only visible after expanding macros let (line_tokens, line_type) = if let LineType::Unknown = line_type { let line_tokens = TokenString::text(self.expand_macros(&line_tokens)?.trim()); // and let's eval whatever bullshit needs evaling #[cfg(feature = "full")] { let eval = self.macros.to_eval.take(); for eval in eval { let child_macros = self.macros.with_overlay(); let child = MakefileReader::read(self.args, child_macros, Cursor::new(eval)) .context("while evaling")? .finish(); self.extend(child); } } let line_type = LineType::of(&line_tokens); (line_tokens, line_type) } else { (line_tokens, line_type) }; match line_type { LineType::Rule => self.read_rule(&line_tokens, line_number)?, LineType::Macro => self.read_macro(line_tokens, line_number)?, LineType::Unknown => { if !line_tokens.is_empty() { bail!( "error: line {}: unknown line \"{}\"", line_number, line_tokens ); } } } } Ok(()) } fn next_line( &mut self, escaped_newline_replacement: &'static str, ) -> Option<(usize, Result)> { while let Some((line_number, line)) = self.lines_iter.next() { let mut line = match line { Ok(x) => x, Err(err) => return Some((line_number, Err(err))), }; // handle escaped newlines while line.ends_with('\\') { line.pop(); line.push_str(escaped_newline_replacement); if let Some((n, x)) = self.lines_iter.next() { let x = match x { Ok(x) => x, Err(err) => return Some((n, Err(err))), }; line.push_str(x.trim_start()) } } // handle comments lazy_static! { static ref COMMENT: Regex = Regex::new("#.*$").unwrap(); } let line = COMMENT.replace(&line, "").into_owned(); #[cfg(feature = "full")] { let cond_line = ConditionalLine::from(&line, |t| self.expand_macros(t)); let cond_line = match cond_line { Ok(x) => x, Err(err) => return Some((line_number, Err(err))), }; if let Some(line) = cond_line { let action = line.action( self.conditional_stack.last(), |name| self.macros.is_defined(name), |t| self.expand_macros(t), ); let action = match action { Ok(x) => x, Err(err) => return Some((line_number, Err(err))), }; action.apply_to(&mut self.conditional_stack); continue; } // skip lines if we need to if self .conditional_stack .last() .map_or(false, ConditionalState::skipping) { continue; } } return Some((line_number, Ok(line))); } None } /// Only applies the predicate to the next physical line in the file. /// Doesn't apply the escaped newline replacement unless the predicate passes. fn next_line_if( &mut self, escaped_newline_replacement: &'static str, predicate: impl FnOnce(&(usize, Result)) -> bool, ) -> Option<(usize, Result)> { if predicate(self.lines_iter.peek()?) { self.next_line(escaped_newline_replacement) } else { None } } fn read_rule(&mut self, line_tokens: &TokenString, line_number: usize) -> Result<()> { let (targets, not_targets) = line_tokens .split_once(':') .ok_or_else(|| eyre!("read_rule couldn't find a ':' on line {}", line_number))?; let targets = self.expand_macros(&targets)?; let targets = targets.split_whitespace().collect::>(); let (prerequisites, mut commands) = match not_targets.split_once(';') { Some((prerequisites, command)) => { // TODO make sure escaped newlines get retroactively treated correctly here (prerequisites, vec![command]) } None => (not_targets, vec![]), }; let prerequisites = self.expand_macros(&prerequisites)?; let prerequisites = prerequisites .split_whitespace() .map(|x| x.into()) .collect::>(); while let Some((_, x)) = self.next_line_if("\\\n", |(_, x)| { x.as_ref() .ok() .map_or(false, |line| line.starts_with('\t') || line.is_empty()) }) { let mut line = x?; if !line.is_empty() { line.remove(0); } if line.is_empty() { continue; } commands.push( line.parse() .with_context(|| format!("failed to parse line {}", line_number))?, ); } let commands = commands .into_iter() .map(CommandLine::from) .collect::>(); if targets.is_empty() { return Ok(()); } // we don't know yet if it's a target rule or an inference rule let inference_match = inference_match(&targets, &prerequisites); if let Some(inference_match) = inference_match { let new_rule = InferenceRule { product: inference_match.name("s1").unwrap().as_str().to_owned(), prereq: inference_match.name("s2").unwrap().as_str().to_owned(), commands, }; self.inference_rules.retain(|existing_rule| { (&existing_rule.prereq, &existing_rule.product) != (&new_rule.prereq, &new_rule.product) }); self.inference_rules.push(new_rule); } else { for target in targets { if self.first_non_special_target.is_none() && !target.starts_with('.') { self.first_non_special_target = Some(target.into()); } match self.targets.get_mut(target) { Some(old_target) if commands.is_empty() && !(target == ".SUFIXES" && prerequisites.is_empty()) => { let new_prerequisites = prerequisites .iter() .filter(|x| !old_target.prerequisites.contains(x)) .cloned() .collect::>(); old_target.prerequisites.extend(new_prerequisites); } _ => { let new_target = Target { name: target.into(), prerequisites: prerequisites.clone(), commands: commands.clone(), already_updated: Cell::new(false), }; self.targets.insert(target.into(), new_target); } } } } Ok(()) } fn read_macro(&mut self, mut line_tokens: TokenString, line_number: usize) -> Result<()> { let (name, mut value) = if cfg!(feature = "full") && line_tokens.starts_with("define ") { line_tokens.strip_prefix("define "); if line_tokens.ends_with("=") { line_tokens.strip_suffix("="); line_tokens.trim_end(); } let mut value = TokenString::empty(); // TODO what should be done with escaped newlines while let Some((_, line)) = self.next_line(" ") { let line = line?; if line == "endef" { break; } if !value.is_empty() { value.extend(TokenString::text("\n")); } value.extend(line.parse()?); } (line_tokens, value) } else { line_tokens .split_once('=') .ok_or_else(|| eyre!("read_rule couldn't find a ':' on line {}", line_number))? }; let name = self.expand_macros(&name)?; // GNUisms are annoying, but popular let mut expand_value = false; let mut skip_if_defined = false; let mut append = false; #[cfg(feature = "full")] let name = if let Some(real_name) = name.strip_suffix("::") { expand_value = true; real_name } else if let Some(real_name) = name.strip_suffix(":") { expand_value = true; real_name } else if let Some(real_name) = name.strip_suffix("?") { skip_if_defined = true; real_name } else if let Some(real_name) = name.strip_suffix("+") { append = true; real_name } else { &name }; let name = name.trim(); value.trim_start(); let value = if expand_value { TokenString::text(self.expand_macros(&value)?) } else { value }; match self.macros.get(name) { // We always let command line or MAKEFLAGS macros override macros from the file. Some((MacroSource::CommandLineOrMakeflags, _)) => return Ok(()), // We let environment variables override macros from the file only if the command-line argument to do that was given Some((MacroSource::Environment, _)) if self.args.environment_overrides => return Ok(()), Some(_) if skip_if_defined => return Ok(()), _ => {} } let value = match self.macros.pop(name) { Some((_, mut old_value)) if append => { // TODO eagerly expand if appending to eagerly-expanded macro old_value.extend(TokenString::text(" ")); old_value.extend(value); old_value } _ => value, }; self.macros.set(name.into(), MacroSource::File, value); Ok(()) } fn expand_macros(&self, text: &TokenString) -> Result { self.macros.expand(text) } pub fn finish(self) -> FinishedMakefileReader { FinishedMakefileReader { inference_rules: self.inference_rules, macros: self.macros.data, targets: self.targets, first_non_special_target: self.first_non_special_target, } } fn extend(&mut self, new: FinishedMakefileReader) { self.inference_rules.extend(new.inference_rules); self.macros.extend(new.macros); self.targets.extend(new.targets); if self.first_non_special_target.is_none() { self.first_non_special_target = new.first_non_special_target; } } } pub struct FinishedMakefileReader { pub inference_rules: Vec, pub macros: HashMap, pub targets: HashMap, pub first_non_special_target: Option, } #[cfg(test)] mod test { use super::*; type R = Result<()>; #[test] fn multi_line_dependencies() -> R { let file = " unrelated: example \tswag x = 3 4 \\ \t\t5 a: $(x) b \\ \t\tc \\ \t\td \tfoo"; let args = Args::empty(); let makefile = MakefileReader::read(&args, MacroSet::new(), Cursor::new(file))?.finish(); assert_eq!( makefile.targets["a"].prerequisites, vec!["3", "4", "5", "b", "c", "d"] ); Ok(()) } #[cfg(feature = "full")] #[test] fn basic_conditionals() -> R { let file = " ifeq (1,1) worked = yes else ifeq (2,2) worked = no else worked = perhaps endif "; let args = Args::empty(); let makefile = MakefileReader::read(&args, MacroSet::new(), Cursor::new(file))?; assert_eq!( makefile.expand_macros(&TokenString::r#macro("worked"))?, "yes" ); Ok(()) } #[cfg(feature = "full")] #[test] fn define_syntax() -> R { let file = " define foo = bar baz endef "; let args = Args::empty(); let makefile = MakefileReader::read(&args, MacroSet::new(), Cursor::new(file))?; assert_eq!( makefile.expand_macros(&TokenString::r#macro("foo"))?, "bar\nbaz" ); Ok(()) } #[test] #[cfg(feature = "full")] fn eval() -> R { // This, for the record, is a terrible misfeature. // If you need this, you probably shouldn't be using Make. // But a lot of people are using this and still use Make anyway, so here we go, // I guess. let file = " PROGRAMS = server client server_OBJS = server.o server_priv.o server_access.o server_LIBS = priv protocol client_OBJS = client.o client_api.o client_mem.o client_LIBS = protocol # Everything after this is generic .PHONY: all all: $(PROGRAMS) define PROGRAM_template = $(1): $$($(1)_OBJS) $$($(1)_LIBS:%=-l%) ALL_OBJS += $$($(1)_OBJS) endef $(foreach prog,$(PROGRAMS),$(eval $(call PROGRAM_template,$(prog)))) $(PROGRAMS): \t$(LINK.o) $^ $(LDLIBS) -o $@ clean: \trm -f $(ALL_OBJS) $(PROGRAMS) "; let args = Args::empty(); let makefile = MakefileReader::read(&args, MacroSet::new(), Cursor::new(file))?; assert!(makefile.targets.contains_key("server")); Ok(()) } }