edify/expr.cpp - platform/bootable/recovery - Git at Google

 /*
  * Copyright (C) 2009 The Android Open Source Project
  *
  * 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.
  */

 #include "edify/expr.h"

 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>

 #include <memory>
 #include <string>
 #include <unordered_map>
 #include <vector>

 #include <android-base/parseint.h>
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>

 #include "otautil/error_code.h"

 // Functions should:
 //
 //    - return a malloc()'d string
 //    - if Evaluate() on any argument returns nullptr, return nullptr.

 static bool BooleanString(const std::string& s) {
     return !s.empty();
 }

 bool Evaluate(State* state, const std::unique_ptr<Expr>& expr, std::string* result) {
     if (result == nullptr) {
         return false;
     }

     std::unique_ptr<Value> v(expr->fn(expr->name.c_str(), state, expr->argv));
     if (!v) {
         return false;
     }
     if (v->type != VAL_STRING) {
         ErrorAbort(state, kArgsParsingFailure, "expecting string, got value type %d", v->type);
         return false;
     }

     *result = v->data;
     return true;
 }

 Value* EvaluateValue(State* state, const std::unique_ptr<Expr>& expr) {
     return expr->fn(expr->name.c_str(), state, expr->argv);
 }

 Value* StringValue(const char* str) {
     if (str == nullptr) {
         return nullptr;
     }
     return new Value(VAL_STRING, str);
 }

 Value* StringValue(const std::string& str) {
     return StringValue(str.c_str());
 }

 Value* ConcatFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
     if (argv.empty()) {
         return StringValue("");
     }
     std::string result;
     for (size_t i = 0; i < argv.size(); ++i) {
         std::string str;
         if (!Evaluate(state, argv[i], &str)) {
             return nullptr;
         }
         result += str;
     }

     return StringValue(result);
 }

 Value* IfElseFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
     if (argv.size() != 2 && argv.size() != 3) {
         state->errmsg = "ifelse expects 2 or 3 arguments";
         return nullptr;
     }

     std::string cond;
     if (!Evaluate(state, argv[0], &cond)) {
         return nullptr;
     }

     if (!cond.empty()) {
         return EvaluateValue(state, argv[1]);
     } else if (argv.size() == 3) {
         return EvaluateValue(state, argv[2]);
     }

     return StringValue("");
 }

 Value* AbortFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
     std::string msg;
     if (!argv.empty() && Evaluate(state, argv[0], &msg)) {
       state->errmsg += msg;
     } else {
       state->errmsg += "called abort()";
     }
     return nullptr;
 }

 Value* AssertFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
     for (size_t i = 0; i < argv.size(); ++i) {
         std::string result;
         if (!Evaluate(state, argv[i], &result)) {
             return nullptr;
         }
         if (result.empty()) {
             int len = argv[i]->end - argv[i]->start;
             state->errmsg = "assert failed: " + state->script.substr(argv[i]->start, len);
             return nullptr;
         }
     }
     return StringValue("");
 }

 Value* SleepFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
     std::string val;
     if (!Evaluate(state, argv[0], &val)) {
         return nullptr;
     }

     int v;
     if (!android::base::ParseInt(val.c_str(), &v, 0)) {
         return nullptr;
     }
     sleep(v);

     return StringValue(val);
 }

 Value* StdoutFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
     for (size_t i = 0; i < argv.size(); ++i) {
         std::string v;
         if (!Evaluate(state, argv[i], &v)) {
             return nullptr;
         }
         fputs(v.c_str(), stdout);
     }
     return StringValue("");
 }

 Value* LogicalAndFn(const char* name, State* state,
                     const std::vector<std::unique_ptr<Expr>>& argv) {
     std::string left;
     if (!Evaluate(state, argv[0], &left)) {
         return nullptr;
     }
     if (BooleanString(left)) {
         return EvaluateValue(state, argv[1]);
     } else {
         return StringValue("");
     }
 }

 Value* LogicalOrFn(const char* name, State* state,
                    const std::vector<std::unique_ptr<Expr>>& argv) {
     std::string left;
     if (!Evaluate(state, argv[0], &left)) {
         return nullptr;
     }
     if (!BooleanString(left)) {
         return EvaluateValue(state, argv[1]);
     } else {
         return StringValue(left);
     }
 }

 Value* LogicalNotFn(const char* name, State* state,
                     const std::vector<std::unique_ptr<Expr>>& argv) {
     std::string val;
     if (!Evaluate(state, argv[0], &val)) {
         return nullptr;
     }

     return StringValue(BooleanString(val) ? "" : "t");
 }

 Value* SubstringFn(const char* name, State* state,
                    const std::vector<std::unique_ptr<Expr>>& argv) {
     std::string needle;
     if (!Evaluate(state, argv[0], &needle)) {
         return nullptr;
     }

     std::string haystack;
     if (!Evaluate(state, argv[1], &haystack)) {
         return nullptr;
     }

     std::string result = (haystack.find(needle) != std::string::npos) ? "t" : "";
     return StringValue(result);
 }

 Value* EqualityFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
     std::string left;
     if (!Evaluate(state, argv[0], &left)) {
         return nullptr;
     }
     std::string right;
     if (!Evaluate(state, argv[1], &right)) {
         return nullptr;
     }

     const char* result = (left == right) ? "t" : "";
     return StringValue(result);
 }

 Value* InequalityFn(const char* name, State* state,
                     const std::vector<std::unique_ptr<Expr>>& argv) {
     std::string left;
     if (!Evaluate(state, argv[0], &left)) {
         return nullptr;
     }
     std::string right;
     if (!Evaluate(state, argv[1], &right)) {
         return nullptr;
     }

     const char* result = (left != right) ? "t" : "";
     return StringValue(result);
 }

 Value* SequenceFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
     std::unique_ptr<Value> left(EvaluateValue(state, argv[0]));
     if (!left) {
         return nullptr;
     }
     return EvaluateValue(state, argv[1]);
 }

 Value* LessThanIntFn(const char* name, State* state,
                      const std::vector<std::unique_ptr<Expr>>& argv) {
     if (argv.size() != 2) {
         state->errmsg = "less_than_int expects 2 arguments";
         return nullptr;
     }

     std::vector<std::string> args;
     if (!ReadArgs(state, argv, &args)) {
         return nullptr;
     }

     // Parse up to at least long long or 64-bit integers.
     int64_t l_int;
     if (!android::base::ParseInt(args[0].c_str(), &l_int)) {
         state->errmsg = "failed to parse int in " + args[0];
         return nullptr;
     }

     int64_t r_int;
     if (!android::base::ParseInt(args[1].c_str(), &r_int)) {
         state->errmsg = "failed to parse int in " + args[1];
         return nullptr;
     }

     return StringValue(l_int < r_int ? "t" : "");
 }

 Value* GreaterThanIntFn(const char* name, State* state,
                         const std::vector<std::unique_ptr<Expr>>& argv) {
     if (argv.size() != 2) {
         state->errmsg = "greater_than_int expects 2 arguments";
         return nullptr;
     }

     std::vector<std::string> args;
     if (!ReadArgs(state, argv, &args)) {
         return nullptr;
     }

     // Parse up to at least long long or 64-bit integers.
     int64_t l_int;
     if (!android::base::ParseInt(args[0].c_str(), &l_int)) {
         state->errmsg = "failed to parse int in " + args[0];
         return nullptr;
     }

     int64_t r_int;
     if (!android::base::ParseInt(args[1].c_str(), &r_int)) {
         state->errmsg = "failed to parse int in " + args[1];
         return nullptr;
     }

     return StringValue(l_int > r_int ? "t" : "");
 }

 Value* Literal(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
     return StringValue(name);
 }

 // -----------------------------------------------------------------
 //   the function table
 // -----------------------------------------------------------------

 static std::unordered_map<std::string, Function> fn_table;

 void RegisterFunction(const std::string& name, Function fn) {
     fn_table[name] = fn;
 }

 Function FindFunction(const std::string& name) {
     if (fn_table.find(name) == fn_table.end()) {
         return nullptr;
     } else {
         return fn_table[name];
     }
 }

 void RegisterBuiltins() {
     RegisterFunction("ifelse", IfElseFn);
     RegisterFunction("abort", AbortFn);
     RegisterFunction("assert", AssertFn);
     RegisterFunction("concat", ConcatFn);
     RegisterFunction("is_substring", SubstringFn);
     RegisterFunction("stdout", StdoutFn);
     RegisterFunction("sleep", SleepFn);

     RegisterFunction("less_than_int", LessThanIntFn);
     RegisterFunction("greater_than_int", GreaterThanIntFn);
 }


 // -----------------------------------------------------------------
 //   convenience methods for functions
 // -----------------------------------------------------------------

 // Evaluate the expressions in argv, and put the results of strings in args. If any expression
 // evaluates to nullptr, return false. Return true on success.
 bool ReadArgs(State* state, const std::vector<std::unique_ptr<Expr>>& argv,
               std::vector<std::string>* args) {
     return ReadArgs(state, argv, args, 0, argv.size());
 }

 bool ReadArgs(State* state, const std::vector<std::unique_ptr<Expr>>& argv,
               std::vector<std::string>* args, size_t start, size_t len) {
     if (args == nullptr) {
         return false;
     }
     if (start + len > argv.size()) {
         return false;
     }
     for (size_t i = start; i < start + len; ++i) {
         std::string var;
         if (!Evaluate(state, argv[i], &var)) {
             args->clear();
             return false;
         }
         args->push_back(var);
     }
     return true;
 }

 // Evaluate the expressions in argv, and put the results of Value* in args. If any expression
 // evaluate to nullptr, return false. Return true on success.
 bool ReadValueArgs(State* state, const std::vector<std::unique_ptr<Expr>>& argv,
                    std::vector<std::unique_ptr<Value>>* args) {
     return ReadValueArgs(state, argv, args, 0, argv.size());
 }

 bool ReadValueArgs(State* state, const std::vector<std::unique_ptr<Expr>>& argv,
                    std::vector<std::unique_ptr<Value>>* args, size_t start, size_t len) {
     if (args == nullptr) {
         return false;
     }
     if (len == 0 || start + len > argv.size()) {
         return false;
     }
     for (size_t i = start; i < start + len; ++i) {
         std::unique_ptr<Value> v(EvaluateValue(state, argv[i]));
         if (!v) {
             args->clear();
             return false;
         }
         args->push_back(std::move(v));
     }
     return true;
 }

 // Use printf-style arguments to compose an error message to put into
 // *state.  Returns nullptr.
 Value* ErrorAbort(State* state, const char* format, ...) {
     va_list ap;
     va_start(ap, format);
     android::base::StringAppendV(&state->errmsg, format, ap);
     va_end(ap);
     return nullptr;
 }

 Value* ErrorAbort(State* state, CauseCode cause_code, const char* format, ...) {
   std::string err_message;
   va_list ap;
   va_start(ap, format);
   android::base::StringAppendV(&err_message, format, ap);
   va_end(ap);
   // Ensure that there's exactly one line break at the end of the error message.
   state->errmsg = android::base::Trim(err_message) + "\n";
   state->cause_code = cause_code;
   return nullptr;
 }

 State::State(const std::string& script, void* cookie)
     : script(script), cookie(cookie), error_code(kNoError), cause_code(kNoCause) {}
	/*
	* Copyright (C) 2009 The Android Open Source Project
	*
	* 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.
	*/

	#include "edify/expr.h"

	#include <stdarg.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <unistd.h>

	#include <memory>
	#include <string>
	#include <unordered_map>
	#include <vector>

	#include <android-base/parseint.h>
	#include <android-base/stringprintf.h>
	#include <android-base/strings.h>

	#include "otautil/error_code.h"

	// Functions should:
	//
	// - return a malloc()'d string
	// - if Evaluate() on any argument returns nullptr, return nullptr.

	static bool BooleanString(const std::string& s) {
	return !s.empty();
	}

	bool Evaluate(State* state, const std::unique_ptr<Expr>& expr, std::string* result) {
	if (result == nullptr) {
	return false;
	}

	std::unique_ptr<Value> v(expr->fn(expr->name.c_str(), state, expr->argv));
	if (!v) {
	return false;
	}
	if (v->type != VAL_STRING) {
	ErrorAbort(state, kArgsParsingFailure, "expecting string, got value type %d", v->type);
	return false;
	}

	*result = v->data;
	return true;
	}

	Value* EvaluateValue(State* state, const std::unique_ptr<Expr>& expr) {
	return expr->fn(expr->name.c_str(), state, expr->argv);
	}

	Value* StringValue(const char* str) {
	if (str == nullptr) {
	return nullptr;
	}
	return new Value(VAL_STRING, str);
	}

	Value* StringValue(const std::string& str) {
	return StringValue(str.c_str());
	}

	Value* ConcatFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
	if (argv.empty()) {
	return StringValue("");
	}
	std::string result;
	for (size_t i = 0; i < argv.size(); ++i) {
	std::string str;
	if (!Evaluate(state, argv[i], &str)) {
	return nullptr;
	}
	result += str;
	}

	return StringValue(result);
	}

	Value* IfElseFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
	if (argv.size() != 2 && argv.size() != 3) {
	state->errmsg = "ifelse expects 2 or 3 arguments";
	return nullptr;
	}

	std::string cond;
	if (!Evaluate(state, argv[0], &cond)) {
	return nullptr;
	}

	if (!cond.empty()) {
	return EvaluateValue(state, argv[1]);
	} else if (argv.size() == 3) {
	return EvaluateValue(state, argv[2]);
	}

	return StringValue("");
	}

	Value* AbortFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
	std::string msg;
	if (!argv.empty() && Evaluate(state, argv[0], &msg)) {
	state->errmsg += msg;
	} else {
	state->errmsg += "called abort()";
	}
	return nullptr;
	}

	Value* AssertFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
	for (size_t i = 0; i < argv.size(); ++i) {
	std::string result;
	if (!Evaluate(state, argv[i], &result)) {
	return nullptr;
	}
	if (result.empty()) {
	int len = argv[i]->end - argv[i]->start;
	state->errmsg = "assert failed: " + state->script.substr(argv[i]->start, len);
	return nullptr;
	}
	}
	return StringValue("");
	}

	Value* SleepFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
	std::string val;
	if (!Evaluate(state, argv[0], &val)) {
	return nullptr;
	}

	int v;
	if (!android::base::ParseInt(val.c_str(), &v, 0)) {
	return nullptr;
	}
	sleep(v);

	return StringValue(val);
	}

	Value* StdoutFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
	for (size_t i = 0; i < argv.size(); ++i) {
	std::string v;
	if (!Evaluate(state, argv[i], &v)) {
	return nullptr;
	}
	fputs(v.c_str(), stdout);
	}
	return StringValue("");
	}

	Value* LogicalAndFn(const char* name, State* state,
	const std::vector<std::unique_ptr<Expr>>& argv) {
	std::string left;
	if (!Evaluate(state, argv[0], &left)) {
	return nullptr;
	}
	if (BooleanString(left)) {
	return EvaluateValue(state, argv[1]);
	} else {
	return StringValue("");
	}
	}

	Value* LogicalOrFn(const char* name, State* state,
	const std::vector<std::unique_ptr<Expr>>& argv) {
	std::string left;
	if (!Evaluate(state, argv[0], &left)) {
	return nullptr;
	}
	if (!BooleanString(left)) {
	return EvaluateValue(state, argv[1]);
	} else {
	return StringValue(left);
	}
	}

	Value* LogicalNotFn(const char* name, State* state,
	const std::vector<std::unique_ptr<Expr>>& argv) {
	std::string val;
	if (!Evaluate(state, argv[0], &val)) {
	return nullptr;
	}

	return StringValue(BooleanString(val) ? "" : "t");
	}

	Value* SubstringFn(const char* name, State* state,
	const std::vector<std::unique_ptr<Expr>>& argv) {
	std::string needle;
	if (!Evaluate(state, argv[0], &needle)) {
	return nullptr;
	}

	std::string haystack;
	if (!Evaluate(state, argv[1], &haystack)) {
	return nullptr;
	}

	std::string result = (haystack.find(needle) != std::string::npos) ? "t" : "";
	return StringValue(result);
	}

	Value* EqualityFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
	std::string left;
	if (!Evaluate(state, argv[0], &left)) {
	return nullptr;
	}
	std::string right;
	if (!Evaluate(state, argv[1], &right)) {
	return nullptr;
	}

	const char* result = (left == right) ? "t" : "";
	return StringValue(result);
	}

	Value* InequalityFn(const char* name, State* state,
	const std::vector<std::unique_ptr<Expr>>& argv) {
	std::string left;
	if (!Evaluate(state, argv[0], &left)) {
	return nullptr;
	}
	std::string right;
	if (!Evaluate(state, argv[1], &right)) {
	return nullptr;
	}

	const char* result = (left != right) ? "t" : "";
	return StringValue(result);
	}

	Value* SequenceFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
	std::unique_ptr<Value> left(EvaluateValue(state, argv[0]));
	if (!left) {
	return nullptr;
	}
	return EvaluateValue(state, argv[1]);
	}

	Value* LessThanIntFn(const char* name, State* state,
	const std::vector<std::unique_ptr<Expr>>& argv) {
	if (argv.size() != 2) {
	state->errmsg = "less_than_int expects 2 arguments";
	return nullptr;
	}

	std::vector<std::string> args;
	if (!ReadArgs(state, argv, &args)) {
	return nullptr;
	}

	// Parse up to at least long long or 64-bit integers.
	int64_t l_int;
	if (!android::base::ParseInt(args[0].c_str(), &l_int)) {
	state->errmsg = "failed to parse int in " + args[0];
	return nullptr;
	}

	int64_t r_int;
	if (!android::base::ParseInt(args[1].c_str(), &r_int)) {
	state->errmsg = "failed to parse int in " + args[1];
	return nullptr;
	}

	return StringValue(l_int < r_int ? "t" : "");
	}

	Value* GreaterThanIntFn(const char* name, State* state,
	const std::vector<std::unique_ptr<Expr>>& argv) {
	if (argv.size() != 2) {
	state->errmsg = "greater_than_int expects 2 arguments";
	return nullptr;
	}

	std::vector<std::string> args;
	if (!ReadArgs(state, argv, &args)) {
	return nullptr;
	}

	// Parse up to at least long long or 64-bit integers.
	int64_t l_int;
	if (!android::base::ParseInt(args[0].c_str(), &l_int)) {
	state->errmsg = "failed to parse int in " + args[0];
	return nullptr;
	}

	int64_t r_int;
	if (!android::base::ParseInt(args[1].c_str(), &r_int)) {
	state->errmsg = "failed to parse int in " + args[1];
	return nullptr;
	}

	return StringValue(l_int > r_int ? "t" : "");
	}

	Value* Literal(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
	return StringValue(name);
	}

	// -----------------------------------------------------------------
	// the function table
	// -----------------------------------------------------------------

	static std::unordered_map<std::string, Function> fn_table;

	void RegisterFunction(const std::string& name, Function fn) {
	fn_table[name] = fn;
	}

	Function FindFunction(const std::string& name) {
	if (fn_table.find(name) == fn_table.end()) {
	return nullptr;
	} else {
	return fn_table[name];
	}
	}

	void RegisterBuiltins() {
	RegisterFunction("ifelse", IfElseFn);
	RegisterFunction("abort", AbortFn);
	RegisterFunction("assert", AssertFn);
	RegisterFunction("concat", ConcatFn);
	RegisterFunction("is_substring", SubstringFn);
	RegisterFunction("stdout", StdoutFn);
	RegisterFunction("sleep", SleepFn);

	RegisterFunction("less_than_int", LessThanIntFn);
	RegisterFunction("greater_than_int", GreaterThanIntFn);
	}


	// -----------------------------------------------------------------
	// convenience methods for functions
	// -----------------------------------------------------------------

	// Evaluate the expressions in argv, and put the results of strings in args. If any expression
	// evaluates to nullptr, return false. Return true on success.
	bool ReadArgs(State* state, const std::vector<std::unique_ptr<Expr>>& argv,
	std::vector<std::string>* args) {
	return ReadArgs(state, argv, args, 0, argv.size());
	}

	bool ReadArgs(State* state, const std::vector<std::unique_ptr<Expr>>& argv,
	std::vector<std::string>* args, size_t start, size_t len) {
	if (args == nullptr) {
	return false;
	}
	if (start + len > argv.size()) {
	return false;
	}
	for (size_t i = start; i < start + len; ++i) {
	std::string var;
	if (!Evaluate(state, argv[i], &var)) {
	args->clear();
	return false;
	}
	args->push_back(var);
	}
	return true;
	}

	// Evaluate the expressions in argv, and put the results of Value* in args. If any expression
	// evaluate to nullptr, return false. Return true on success.
	bool ReadValueArgs(State* state, const std::vector<std::unique_ptr<Expr>>& argv,
	std::vector<std::unique_ptr<Value>>* args) {
	return ReadValueArgs(state, argv, args, 0, argv.size());
	}

	bool ReadValueArgs(State* state, const std::vector<std::unique_ptr<Expr>>& argv,
	std::vector<std::unique_ptr<Value>>* args, size_t start, size_t len) {
	if (args == nullptr) {
	return false;
	}
	if (len == 0 \|\| start + len > argv.size()) {
	return false;
	}
	for (size_t i = start; i < start + len; ++i) {
	std::unique_ptr<Value> v(EvaluateValue(state, argv[i]));
	if (!v) {
	args->clear();
	return false;
	}
	args->push_back(std::move(v));
	}
	return true;
	}

	// Use printf-style arguments to compose an error message to put into
	// *state. Returns nullptr.
	Value* ErrorAbort(State* state, const char* format, ...) {
	va_list ap;
	va_start(ap, format);
	android::base::StringAppendV(&state->errmsg, format, ap);
	va_end(ap);
	return nullptr;
	}

	Value* ErrorAbort(State* state, CauseCode cause_code, const char* format, ...) {
	std::string err_message;
	va_list ap;
	va_start(ap, format);
	android::base::StringAppendV(&err_message, format, ap);
	va_end(ap);
	// Ensure that there's exactly one line break at the end of the error message.
	state->errmsg = android::base::Trim(err_message) + "\n";
	state->cause_code = cause_code;
	return nullptr;
	}

	State::State(const std::string& script, void* cookie)
	: script(script), cookie(cookie), error_code(kNoError), cause_code(kNoCause) {}