/*
* 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 "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>
// 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, Expr* expr, std::string* result) {
if (result == nullptr) {
return false;
}
std::unique_ptr<Value> v(expr->fn(expr->name, state, expr->argc, 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, Expr* expr) {
return expr->fn(expr->name, state, expr->argc, 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, int argc, Expr* argv[]) {
if (argc == 0) {
return StringValue("");
}
std::string result;
for (int i = 0; i < argc; ++i) {
std::string str;
if (!Evaluate(state, argv[i], &str)) {
return nullptr;
}
result += str;
}
return StringValue(result);
}
Value* IfElseFn(const char* name, State* state, int argc, Expr* argv[]) {
if (argc != 2 && argc != 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 (argc == 3) {
return EvaluateValue(state, argv[2]);
}
return StringValue("");
}
Value* AbortFn(const char* name, State* state, int argc, Expr* argv[]) {
std::string msg;
if (argc > 0 && Evaluate(state, argv[0], &msg)) {
state->errmsg = msg;
} else {
state->errmsg = "called abort()";
}
return nullptr;
}
Value* AssertFn(const char* name, State* state, int argc, Expr* argv[]) {
for (int i = 0; i < argc; ++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, int argc, 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, int argc, Expr* argv[]) {
for (int i = 0; i < argc; ++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,
int argc, 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,
int argc, 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,
int argc, 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,
int argc, 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, int argc, 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, int argc, 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, int argc, 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, int argc, Expr* argv[]) {
if (argc != 2) {
state->errmsg = "less_than_int expects 2 arguments";
return nullptr;
}
char* left;
char* right;
if (ReadArgs(state, argv, 2, &left, &right) < 0) return nullptr;
bool result = false;
char* end;
// Parse up to at least long long or 64-bit integers.
int64_t l_int = static_cast<int64_t>(strtoll(left, &end, 10));
if (left[0] == '\0' || *end != '\0') {
goto done;
}
int64_t r_int;
r_int = static_cast<int64_t>(strtoll(right, &end, 10));
if (right[0] == '\0' || *end != '\0') {
goto done;
}
result = l_int < r_int;
done:
free(left);
free(right);
return StringValue(result ? "t" : "");
}
Value* GreaterThanIntFn(const char* name, State* state,
int argc, Expr* argv[]) {
if (argc != 2) {
state->errmsg = "greater_than_int expects 2 arguments";
return nullptr;
}
Expr* temp[2];
temp[0] = argv[1];
temp[1] = argv[0];
return LessThanIntFn(name, state, 2, temp);
}
Value* Literal(const char* name, State* state, int argc, 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, free the rest and return
// false. Return true on success.
bool ReadArgs(State* state, int argc, Expr* argv[], std::vector<std::string>* args) {
if (args == nullptr) {
return false;
}
for (int i = 0; i < argc; ++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, free the rest and return
// false. Return true on success.
bool ReadValueArgs(State* state, int argc, Expr* argv[],
std::vector<std::unique_ptr<Value>>* args) {
if (args == nullptr) {
return false;
}
for (int i = 0; i < argc; ++i) {
std::unique_ptr<Value> v(EvaluateValue(state, argv[i]));
if (!v) {
args->clear();
return false;
}
args->push_back(std::move(v));
}
return true;
}
// Evaluate the expressions in argv, giving 'count' char* (the ... is
// zero or more char** to put them in). If any expression evaluates
// to NULL, free the rest and return -1. Return 0 on success.
int ReadArgs(State* state, Expr* argv[], int count, ...) {
char** args = reinterpret_cast<char**>(malloc(count * sizeof(char*)));
va_list v;
va_start(v, count);
int i;
for (i = 0; i < count; ++i) {
std::string str;
if (!Evaluate(state, argv[i], &str) ||
(args[i] = strdup(str.c_str())) == nullptr) {
va_end(v);
int j;
for (j = 0; j < i; ++j) {
free(args[j]);
}
free(args);
return -1;
}
*(va_arg(v, char**)) = args[i];
}
va_end(v);
free(args);
return 0;
}
// Evaluate the expressions in argv, giving 'count' Value* (the ... is
// zero or more Value** to put them in). If any expression evaluates
// to NULL, free the rest and return -1. Return 0 on success.
int ReadValueArgs(State* state, Expr* argv[], int count, ...) {
Value** args = new Value*[count];
va_list v;
va_start(v, count);
for (int i = 0; i < count; ++i) {
args[i] = EvaluateValue(state, argv[i]);
if (args[i] == NULL) {
va_end(v);
int j;
for (j = 0; j < i; ++j) {
delete args[j];
}
delete[] args;
return -1;
}
*(va_arg(v, Value**)) = args[i];
}
va_end(v);
delete[] args;
return 0;
}
// Evaluate the expressions in argv, returning an array of char*
// results. If any evaluate to NULL, free the rest and return NULL.
// The caller is responsible for freeing the returned array and the
// strings it contains.
char** ReadVarArgs(State* state, int argc, Expr* argv[]) {
char** args = (char**)malloc(argc * sizeof(char*));
for (int i = 0; i < argc; ++i) {
std::string str;
if (!Evaluate(state, argv[i], &str) ||
(args[i] = strdup(str.c_str())) == nullptr) {
for (int j = 0; j < i; ++j) {
free(args[j]);
}
free(args);
return NULL;
}
}
return args;
}
// Evaluate the expressions in argv, returning an array of Value*
// results. If any evaluate to NULL, free the rest and return NULL.
// The caller is responsible for freeing the returned array and the
// Values it contains.
Value** ReadValueVarArgs(State* state, int argc, Expr* argv[]) {
Value** args = new Value*[argc];
int i = 0;
for (i = 0; i < argc; ++i) {
args[i] = EvaluateValue(state, argv[i]);
if (args[i] == NULL) {
int j;
for (j = 0; j < i; ++j) {
delete args[j];
}
delete[] args;
return NULL;
}
}
return args;
}
// 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, ...) {
va_list ap;
va_start(ap, format);
android::base::StringAppendV(&state->errmsg, format, ap);
va_end(ap);
state->cause_code = cause_code;
return nullptr;
}
State::State(const std::string& script, void* cookie) :
script(script),
cookie(cookie) {
}
