eval.cc - platform/build/kati - Git at Google

 // Copyright 2015 Google Inc. All rights reserved
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //      http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.

 // +build ignore

 #include "eval.h"

 #include <errno.h>
 #include <string.h>

 #include "expr.h"
 #include "file.h"
 #include "file_cache.h"
 #include "fileutil.h"
 #include "parser.h"
 #include "rule.h"
 #include "stmt.h"
 #include "strutil.h"
 #include "symtab.h"
 #include "var.h"

 Evaluator::Evaluator()
     : last_rule_(NULL),
       current_scope_(NULL),
       avoid_io_(false),
       eval_depth_(0),
       posix_sym_(Intern(".POSIX")),
       is_posix_(false) {
 }

 Evaluator::~Evaluator() {
   // delete vars_;
   // for (auto p : rule_vars) {
   //   delete p.second;
   // }
 }

 Var* Evaluator::EvalRHS(Symbol lhs, Value* rhs_v, StringPiece orig_rhs,
                         AssignOp op, bool is_override) {
   VarOrigin origin = (
       (is_bootstrap_ ? VarOrigin::DEFAULT :
        is_override ? VarOrigin::OVERRIDE : VarOrigin::FILE));

   Var* rhs = NULL;
   bool needs_assign = true;
   switch (op) {
     case AssignOp::COLON_EQ: {
       SimpleVar* sv = new SimpleVar(origin);
       rhs_v->Eval(this, sv->mutable_value());
       rhs = sv;
       break;
     }
     case AssignOp::EQ:
       rhs = new RecursiveVar(rhs_v, origin, orig_rhs);
       break;
     case AssignOp::PLUS_EQ: {
       Var* prev = LookupVarInCurrentScope(lhs);
       if (!prev->IsDefined()) {
         rhs = new RecursiveVar(rhs_v, origin, orig_rhs);
       } else {
         prev->AppendVar(this, rhs_v);
         rhs = prev;
         needs_assign = false;
       }
       break;
     }
     case AssignOp::QUESTION_EQ: {
       Var* prev = LookupVarInCurrentScope(lhs);
       if (!prev->IsDefined()) {
         rhs = new RecursiveVar(rhs_v, origin, orig_rhs);
       } else {
         rhs = prev;
         needs_assign = false;
       }
       break;
     }
   }

   LOG("Assign: %s=%s", lhs.c_str(), rhs->DebugString().c_str());
   if (needs_assign) {
     return rhs;
   }
   return NULL;
 }

 void Evaluator::EvalAssign(const AssignStmt* stmt) {
   loc_ = stmt->loc();
   last_rule_ = NULL;
   Symbol lhs = stmt->GetLhsSymbol(this);
   if (lhs.empty())
     Error("*** empty variable name.");
   Var* rhs = EvalRHS(lhs, stmt->rhs, stmt->orig_rhs, stmt->op,
                      stmt->directive == AssignDirective::OVERRIDE);
   if (rhs)
     lhs.SetGlobalVar(rhs,
                      stmt->directive == AssignDirective::OVERRIDE);
 }

 void Evaluator::EvalRule(const RuleStmt* stmt) {
   loc_ = stmt->loc();
   last_rule_ = NULL;

   const string&& expr = stmt->expr->Eval(this);
   // See semicolon.mk.
   if (expr.find_first_not_of(" \t;") == string::npos) {
     if (stmt->term == ';')
       Error("*** missing rule before commands.");
     return;
   }

   Rule* rule;
   RuleVarAssignment rule_var;
   ParseRule(loc_, expr, stmt->term, &rule, &rule_var);

   if (rule) {
     if (stmt->term == ';') {
       rule->cmds.push_back(stmt->after_term);
     }

     for (Symbol o : rule->outputs) {
       if (o == posix_sym_)
         is_posix_ = true;
     }

     LOG("Rule: %s", rule->DebugString().c_str());
     rules_.push_back(rule);
     last_rule_ = rule;
     return;
   }

   Symbol lhs = Intern(rule_var.lhs);
   for (Symbol output : rule_var.outputs) {
     auto p = rule_vars_.emplace(output, nullptr);
     if (p.second) {
       p.first->second = new Vars;
     }

     Value* rhs = stmt->after_term;
     if (!rule_var.rhs.empty()) {
       Value* lit = NewLiteral(rule_var.rhs);
       if (rhs) {
         // TODO: We always insert two whitespaces around the
         // terminator. Preserve whitespaces properly.
         if (stmt->term == ';') {
           rhs = NewExpr3(lit, NewLiteral(StringPiece(" ; ")), rhs);
         } else {
           rhs = NewExpr3(lit, NewLiteral(StringPiece(" = ")), rhs);
         }
       } else {
         rhs = lit;
       }
     }

     current_scope_ = p.first->second;
     Var* rhs_var = EvalRHS(lhs, rhs, StringPiece("*TODO*"), rule_var.op);
     if (rhs_var)
       current_scope_->Assign(lhs, new RuleVar(rhs_var, rule_var.op));
     current_scope_ = NULL;
   }
 }

 void Evaluator::EvalCommand(const CommandStmt* stmt) {
   loc_ = stmt->loc();

   if (!last_rule_) {
     vector<Stmt*> stmts;
     ParseNotAfterRule(stmt->orig, stmt->loc(), &stmts);
     for (Stmt* a : stmts)
       a->Eval(this);
     return;
   }

   last_rule_->cmds.push_back(stmt->expr);
   if (last_rule_->cmd_lineno == 0)
     last_rule_->cmd_lineno = stmt->loc().lineno;
   LOG("Command: %s", stmt->expr->DebugString().c_str());
 }

 void Evaluator::EvalIf(const IfStmt* stmt) {
   loc_ = stmt->loc();

   bool is_true;
   switch (stmt->op) {
     case CondOp::IFDEF:
     case CondOp::IFNDEF: {
       string var_name;
       stmt->lhs->Eval(this, &var_name);
       Symbol lhs = Intern(TrimRightSpace(var_name));
       if (lhs.str().find_first_of(" \t") != string::npos)
         Error("*** invalid syntax in conditional.");
       Var* v = LookupVarInCurrentScope(lhs);
       const string&& s = v->Eval(this);
       is_true = (s.empty() == (stmt->op == CondOp::IFNDEF));
       break;
     }
     case CondOp::IFEQ:
     case CondOp::IFNEQ: {
       const string&& lhs = stmt->lhs->Eval(this);
       const string&& rhs = stmt->rhs->Eval(this);
       is_true = ((lhs == rhs) == (stmt->op == CondOp::IFEQ));
       break;
     }
     default:
       CHECK(false);
       abort();
   }

   const vector<Stmt*>* stmts;
   if (is_true) {
     stmts = &stmt->true_stmts;
   } else {
     stmts = &stmt->false_stmts;
   }
   for (Stmt* a : *stmts) {
     LOG("%s", a->DebugString().c_str());
     a->Eval(this);
   }
 }

 void Evaluator::DoInclude(const string& fname) {
   Makefile* mk = MakefileCacheManager::Get()->ReadMakefile(fname);
   CHECK(mk->Exists());

   Var* var_list = LookupVar(Intern("MAKEFILE_LIST"));
   var_list->AppendVar(this, NewLiteral(Intern(TrimLeadingCurdir(fname)).str()));
   for (Stmt* stmt : mk->stmts()) {
     LOG("%s", stmt->DebugString().c_str());
     stmt->Eval(this);
   }
 }

 void Evaluator::EvalInclude(const IncludeStmt* stmt) {
   loc_ = stmt->loc();
   last_rule_ = NULL;

   const string&& pats = stmt->expr->Eval(this);
   for (StringPiece pat : WordScanner(pats)) {
     ScopedTerminator st(pat);
     vector<string>* files;
     Glob(pat.data(), &files);

     if (stmt->should_exist) {
       if (files->empty()) {
         // TOOD: Kati does not support building a missing include file.
         Error(StringPrintf("%s: %s", pat.data(), strerror(errno)));
       }
     }

     for (const string& fname : *files) {
       if (!stmt->should_exist && g_flags.ignore_optional_include_pattern &&
           Pattern(g_flags.ignore_optional_include_pattern).Match(fname)) {
         continue;
       }
       DoInclude(fname);
     }
   }
 }

 void Evaluator::EvalExport(const ExportStmt* stmt) {
   loc_ = stmt->loc();
   last_rule_ = NULL;

   const string&& exports = stmt->expr->Eval(this);
   for (StringPiece tok : WordScanner(exports)) {
     size_t equal_index = tok.find('=');
     if (equal_index == string::npos) {
       exports_[Intern(tok)] = stmt->is_export;
     } else if (equal_index == 0 ||
                (equal_index == 1 &&
                 (tok[0] == ':' || tok[0] == '?' || tok[0] == '+'))) {
       // Do not export tokens after an assignment.
       break;
     } else {
       StringPiece lhs, rhs;
       AssignOp op;
       ParseAssignStatement(tok, equal_index, &lhs, &rhs, &op);
       exports_[Intern(lhs)] = stmt->is_export;
     }
   }
 }

 Var* Evaluator::LookupVarGlobal(Symbol name) {
   Var* v = name.GetGlobalVar();
   if (v->IsDefined())
     return v;
   used_undefined_vars_.insert(name);
   return v;
 }

 Var* Evaluator::LookupVar(Symbol name) {
   if (current_scope_) {
     Var* v = current_scope_->Lookup(name);
     if (v->IsDefined())
       return v;
   }
   return LookupVarGlobal(name);
 }

 Var* Evaluator::LookupVarInCurrentScope(Symbol name) {
   if (current_scope_) {
     return current_scope_->Lookup(name);
   }
   return LookupVarGlobal(name);
 }

 string Evaluator::EvalVar(Symbol name) {
   return LookupVar(name)->Eval(this);
 }

 string Evaluator::GetShell() {
   return EvalVar(kShellSym);
 }

 string Evaluator::GetShellFlag() {
   // TODO: Handle $(.SHELLFLAGS)
   return is_posix_ ? "-ec" : "-c";
 }

 string Evaluator::GetShellAndFlag() {
   string shell = GetShell();
   shell += ' ';
   shell += GetShellFlag();
   return shell;
 }

 void Evaluator::Error(const string& msg) {
   ERROR("%s:%d: %s", LOCF(loc_), msg.c_str());
 }

 unordered_set<Symbol> Evaluator::used_undefined_vars_;
	// Copyright 2015 Google Inc. All rights reserved
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.

	// +build ignore

	#include "eval.h"

	#include <errno.h>
	#include <string.h>

	#include "expr.h"
	#include "file.h"
	#include "file_cache.h"
	#include "fileutil.h"
	#include "parser.h"
	#include "rule.h"
	#include "stmt.h"
	#include "strutil.h"
	#include "symtab.h"
	#include "var.h"

	Evaluator::Evaluator()
	: last_rule_(NULL),
	current_scope_(NULL),
	avoid_io_(false),
	eval_depth_(0),
	posix_sym_(Intern(".POSIX")),
	is_posix_(false) {
	}

	Evaluator::~Evaluator() {
	// delete vars_;
	// for (auto p : rule_vars) {
	// delete p.second;
	// }
	}

	Var* Evaluator::EvalRHS(Symbol lhs, Value* rhs_v, StringPiece orig_rhs,
	AssignOp op, bool is_override) {
	VarOrigin origin = (
	(is_bootstrap_ ? VarOrigin::DEFAULT :
	is_override ? VarOrigin::OVERRIDE : VarOrigin::FILE));

	Var* rhs = NULL;
	bool needs_assign = true;
	switch (op) {
	case AssignOp::COLON_EQ: {
	SimpleVar* sv = new SimpleVar(origin);
	rhs_v->Eval(this, sv->mutable_value());
	rhs = sv;
	break;
	}
	case AssignOp::EQ:
	rhs = new RecursiveVar(rhs_v, origin, orig_rhs);
	break;
	case AssignOp::PLUS_EQ: {
	Var* prev = LookupVarInCurrentScope(lhs);
	if (!prev->IsDefined()) {
	rhs = new RecursiveVar(rhs_v, origin, orig_rhs);
	} else {
	prev->AppendVar(this, rhs_v);
	rhs = prev;
	needs_assign = false;
	}
	break;
	}
	case AssignOp::QUESTION_EQ: {
	Var* prev = LookupVarInCurrentScope(lhs);
	if (!prev->IsDefined()) {
	rhs = new RecursiveVar(rhs_v, origin, orig_rhs);
	} else {
	rhs = prev;
	needs_assign = false;
	}
	break;
	}
	}

	LOG("Assign: %s=%s", lhs.c_str(), rhs->DebugString().c_str());
	if (needs_assign) {
	return rhs;
	}
	return NULL;
	}

	void Evaluator::EvalAssign(const AssignStmt* stmt) {
	loc_ = stmt->loc();
	last_rule_ = NULL;
	Symbol lhs = stmt->GetLhsSymbol(this);
	if (lhs.empty())
	Error("*** empty variable name.");
	Var* rhs = EvalRHS(lhs, stmt->rhs, stmt->orig_rhs, stmt->op,
	stmt->directive == AssignDirective::OVERRIDE);
	if (rhs)
	lhs.SetGlobalVar(rhs,
	stmt->directive == AssignDirective::OVERRIDE);
	}

	void Evaluator::EvalRule(const RuleStmt* stmt) {
	loc_ = stmt->loc();
	last_rule_ = NULL;

	const string&& expr = stmt->expr->Eval(this);
	// See semicolon.mk.
	if (expr.find_first_not_of(" \t;") == string::npos) {
	if (stmt->term == ';')
	Error("*** missing rule before commands.");
	return;
	}

	Rule* rule;
	RuleVarAssignment rule_var;
	ParseRule(loc_, expr, stmt->term, &rule, &rule_var);

	if (rule) {
	if (stmt->term == ';') {
	rule->cmds.push_back(stmt->after_term);
	}

	for (Symbol o : rule->outputs) {
	if (o == posix_sym_)
	is_posix_ = true;
	}

	LOG("Rule: %s", rule->DebugString().c_str());
	rules_.push_back(rule);
	last_rule_ = rule;
	return;
	}

	Symbol lhs = Intern(rule_var.lhs);
	for (Symbol output : rule_var.outputs) {
	auto p = rule_vars_.emplace(output, nullptr);
	if (p.second) {
	p.first->second = new Vars;
	}

	Value* rhs = stmt->after_term;
	if (!rule_var.rhs.empty()) {
	Value* lit = NewLiteral(rule_var.rhs);
	if (rhs) {
	// TODO: We always insert two whitespaces around the
	// terminator. Preserve whitespaces properly.
	if (stmt->term == ';') {
	rhs = NewExpr3(lit, NewLiteral(StringPiece(" ; ")), rhs);
	} else {
	rhs = NewExpr3(lit, NewLiteral(StringPiece(" = ")), rhs);
	}
	} else {
	rhs = lit;
	}
	}

	current_scope_ = p.first->second;
	Var* rhs_var = EvalRHS(lhs, rhs, StringPiece("TODO"), rule_var.op);
	if (rhs_var)
	current_scope_->Assign(lhs, new RuleVar(rhs_var, rule_var.op));
	current_scope_ = NULL;
	}
	}

	void Evaluator::EvalCommand(const CommandStmt* stmt) {
	loc_ = stmt->loc();

	if (!last_rule_) {
	vector<Stmt*> stmts;
	ParseNotAfterRule(stmt->orig, stmt->loc(), &stmts);
	for (Stmt* a : stmts)
	a->Eval(this);
	return;
	}

	last_rule_->cmds.push_back(stmt->expr);
	if (last_rule_->cmd_lineno == 0)
	last_rule_->cmd_lineno = stmt->loc().lineno;
	LOG("Command: %s", stmt->expr->DebugString().c_str());
	}

	void Evaluator::EvalIf(const IfStmt* stmt) {
	loc_ = stmt->loc();

	bool is_true;
	switch (stmt->op) {
	case CondOp::IFDEF:
	case CondOp::IFNDEF: {
	string var_name;
	stmt->lhs->Eval(this, &var_name);
	Symbol lhs = Intern(TrimRightSpace(var_name));
	if (lhs.str().find_first_of(" \t") != string::npos)
	Error("*** invalid syntax in conditional.");
	Var* v = LookupVarInCurrentScope(lhs);
	const string&& s = v->Eval(this);
	is_true = (s.empty() == (stmt->op == CondOp::IFNDEF));
	break;
	}
	case CondOp::IFEQ:
	case CondOp::IFNEQ: {
	const string&& lhs = stmt->lhs->Eval(this);
	const string&& rhs = stmt->rhs->Eval(this);
	is_true = ((lhs == rhs) == (stmt->op == CondOp::IFEQ));
	break;
	}
	default:
	CHECK(false);
	abort();
	}

	const vector<Stmt> stmts;
	if (is_true) {
	stmts = &stmt->true_stmts;
	} else {
	stmts = &stmt->false_stmts;
	}
	for (Stmt* a : *stmts) {
	LOG("%s", a->DebugString().c_str());
	a->Eval(this);
	}
	}

	void Evaluator::DoInclude(const string& fname) {
	Makefile* mk = MakefileCacheManager::Get()->ReadMakefile(fname);
	CHECK(mk->Exists());

	Var* var_list = LookupVar(Intern("MAKEFILE_LIST"));
	var_list->AppendVar(this, NewLiteral(Intern(TrimLeadingCurdir(fname)).str()));
	for (Stmt* stmt : mk->stmts()) {
	LOG("%s", stmt->DebugString().c_str());
	stmt->Eval(this);
	}
	}

	void Evaluator::EvalInclude(const IncludeStmt* stmt) {
	loc_ = stmt->loc();
	last_rule_ = NULL;

	const string&& pats = stmt->expr->Eval(this);
	for (StringPiece pat : WordScanner(pats)) {
	ScopedTerminator st(pat);
	vector<string>* files;
	Glob(pat.data(), &files);

	if (stmt->should_exist) {
	if (files->empty()) {
	// TOOD: Kati does not support building a missing include file.
	Error(StringPrintf("%s: %s", pat.data(), strerror(errno)));
	}
	}

	for (const string& fname : *files) {
	if (!stmt->should_exist && g_flags.ignore_optional_include_pattern &&
	Pattern(g_flags.ignore_optional_include_pattern).Match(fname)) {
	continue;
	}
	DoInclude(fname);
	}
	}
	}

	void Evaluator::EvalExport(const ExportStmt* stmt) {
	loc_ = stmt->loc();
	last_rule_ = NULL;

	const string&& exports = stmt->expr->Eval(this);
	for (StringPiece tok : WordScanner(exports)) {
	size_t equal_index = tok.find('=');
	if (equal_index == string::npos) {
	exports_[Intern(tok)] = stmt->is_export;
	} else if (equal_index == 0 \|\|
	(equal_index == 1 &&
	(tok[0] == ':' \|\| tok[0] == '?' \|\| tok[0] == '+'))) {
	// Do not export tokens after an assignment.
	break;
	} else {
	StringPiece lhs, rhs;
	AssignOp op;
	ParseAssignStatement(tok, equal_index, &lhs, &rhs, &op);
	exports_[Intern(lhs)] = stmt->is_export;
	}
	}
	}

	Var* Evaluator::LookupVarGlobal(Symbol name) {
	Var* v = name.GetGlobalVar();
	if (v->IsDefined())
	return v;
	used_undefined_vars_.insert(name);
	return v;
	}

	Var* Evaluator::LookupVar(Symbol name) {
	if (current_scope_) {
	Var* v = current_scope_->Lookup(name);
	if (v->IsDefined())
	return v;
	}
	return LookupVarGlobal(name);
	}

	Var* Evaluator::LookupVarInCurrentScope(Symbol name) {
	if (current_scope_) {
	return current_scope_->Lookup(name);
	}
	return LookupVarGlobal(name);
	}

	string Evaluator::EvalVar(Symbol name) {
	return LookupVar(name)->Eval(this);
	}

	string Evaluator::GetShell() {
	return EvalVar(kShellSym);
	}

	string Evaluator::GetShellFlag() {
	// TODO: Handle $(.SHELLFLAGS)
	return is_posix_ ? "-ec" : "-c";
	}

	string Evaluator::GetShellAndFlag() {
	string shell = GetShell();
	shell += ' ';
	shell += GetShellFlag();
	return shell;
	}

	void Evaluator::Error(const string& msg) {
	ERROR("%s:%d: %s", LOCF(loc_), msg.c_str());
	}

	unordered_set<Symbol> Evaluator::used_undefined_vars_;