/*
* 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 <string.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <unistd.h>
#include "expr.h"
// Functions should:
//
// - return a malloc()'d string
// - if Evaluate() on any argument returns NULL, return NULL.
int BooleanString(const char* s) {
return s[0] != '\0';
}
char* Evaluate(State* state, Expr* expr) {
Value* v = expr->fn(expr->name, state, expr->argc, expr->argv);
if (v == NULL) return NULL;
if (v->type != VAL_STRING) {
ErrorAbort(state, "expecting string, got value type %d", v->type);
FreeValue(v);
return NULL;
}
char* result = v->data;
free(v);
return result;
}
Value* EvaluateValue(State* state, Expr* expr) {
return expr->fn(expr->name, state, expr->argc, expr->argv);
}
Value* StringValue(char* str) {
if (str == NULL) return NULL;
Value* v = malloc(sizeof(Value));
v->type = VAL_STRING;
v->size = strlen(str);
v->data = str;
return v;
}
void FreeValue(Value* v) {
if (v == NULL) return;
free(v->data);
free(v);
}
Value* ConcatFn(const char* name, State* state, int argc, Expr* argv[]) {
if (argc == 0) {
return StringValue(strdup(""));
}
char** strings = malloc(argc * sizeof(char*));
int i;
for (i = 0; i < argc; ++i) {
strings[i] = NULL;
}
char* result = NULL;
int length = 0;
for (i = 0; i < argc; ++i) {
strings[i] = Evaluate(state, argv[i]);
if (strings[i] == NULL) {
goto done;
}
length += strlen(strings[i]);
}
result = malloc(length+1);
int p = 0;
for (i = 0; i < argc; ++i) {
strcpy(result+p, strings[i]);
p += strlen(strings[i]);
}
result[p] = '\0';
done:
for (i = 0; i < argc; ++i) {
free(strings[i]);
}
free(strings);
return StringValue(result);
}
Value* IfElseFn(const char* name, State* state, int argc, Expr* argv[]) {
if (argc != 2 && argc != 3) {
free(state->errmsg);
state->errmsg = strdup("ifelse expects 2 or 3 arguments");
return NULL;
}
char* cond = Evaluate(state, argv[0]);
if (cond == NULL) {
return NULL;
}
if (BooleanString(cond) == true) {
free(cond);
return EvaluateValue(state, argv[1]);
} else {
if (argc == 3) {
free(cond);
return EvaluateValue(state, argv[2]);
} else {
return StringValue(cond);
}
}
}
Value* AbortFn(const char* name, State* state, int argc, Expr* argv[]) {
char* msg = NULL;
if (argc > 0) {
msg = Evaluate(state, argv[0]);
}
free(state->errmsg);
if (msg) {
state->errmsg = msg;
} else {
state->errmsg = strdup("called abort()");
}
return NULL;
}
Value* AssertFn(const char* name, State* state, int argc, Expr* argv[]) {
int i;
for (i = 0; i < argc; ++i) {
char* v = Evaluate(state, argv[i]);
if (v == NULL) {
return NULL;
}
int b = BooleanString(v);
free(v);
if (!b) {
int prefix_len;
int len = argv[i]->end - argv[i]->start;
char* err_src = malloc(len + 20);
strcpy(err_src, "assert failed: ");
prefix_len = strlen(err_src);
memcpy(err_src + prefix_len, state->script + argv[i]->start, len);
err_src[prefix_len + len] = '\0';
free(state->errmsg);
state->errmsg = err_src;
return NULL;
}
}
return StringValue(strdup(""));
}
Value* SleepFn(const char* name, State* state, int argc, Expr* argv[]) {
char* val = Evaluate(state, argv[0]);
if (val == NULL) {
return NULL;
}
int v = strtol(val, NULL, 10);
sleep(v);
return StringValue(val);
}
Value* StdoutFn(const char* name, State* state, int argc, Expr* argv[]) {
int i;
for (i = 0; i < argc; ++i) {
char* v = Evaluate(state, argv[i]);
if (v == NULL) {
return NULL;
}
fputs(v, stdout);
free(v);
}
return StringValue(strdup(""));
}
Value* LogicalAndFn(const char* name, State* state,
int argc, Expr* argv[]) {
char* left = Evaluate(state, argv[0]);
if (left == NULL) return NULL;
if (BooleanString(left) == true) {
free(left);
return EvaluateValue(state, argv[1]);
} else {
return StringValue(left);
}
}
Value* LogicalOrFn(const char* name, State* state,
int argc, Expr* argv[]) {
char* left = Evaluate(state, argv[0]);
if (left == NULL) return NULL;
if (BooleanString(left) == false) {
free(left);
return EvaluateValue(state, argv[1]);
} else {
return StringValue(left);
}
}
Value* LogicalNotFn(const char* name, State* state,
int argc, Expr* argv[]) {
char* val = Evaluate(state, argv[0]);
if (val == NULL) return NULL;
bool bv = BooleanString(val);
free(val);
return StringValue(strdup(bv ? "" : "t"));
}
Value* SubstringFn(const char* name, State* state,
int argc, Expr* argv[]) {
char* needle = Evaluate(state, argv[0]);
if (needle == NULL) return NULL;
char* haystack = Evaluate(state, argv[1]);
if (haystack == NULL) {
free(needle);
return NULL;
}
char* result = strdup(strstr(haystack, needle) ? "t" : "");
free(needle);
free(haystack);
return StringValue(result);
}
Value* EqualityFn(const char* name, State* state, int argc, Expr* argv[]) {
char* left = Evaluate(state, argv[0]);
if (left == NULL) return NULL;
char* right = Evaluate(state, argv[1]);
if (right == NULL) {
free(left);
return NULL;
}
char* result = strdup(strcmp(left, right) == 0 ? "t" : "");
free(left);
free(right);
return StringValue(result);
}
Value* InequalityFn(const char* name, State* state, int argc, Expr* argv[]) {
char* left = Evaluate(state, argv[0]);
if (left == NULL) return NULL;
char* right = Evaluate(state, argv[1]);
if (right == NULL) {
free(left);
return NULL;
}
char* result = strdup(strcmp(left, right) != 0 ? "t" : "");
free(left);
free(right);
return StringValue(result);
}
Value* SequenceFn(const char* name, State* state, int argc, Expr* argv[]) {
Value* left = EvaluateValue(state, argv[0]);
if (left == NULL) return NULL;
FreeValue(left);
return EvaluateValue(state, argv[1]);
}
Value* LessThanIntFn(const char* name, State* state, int argc, Expr* argv[]) {
if (argc != 2) {
free(state->errmsg);
state->errmsg = strdup("less_than_int expects 2 arguments");
return NULL;
}
char* left;
char* right;
if (ReadArgs(state, argv, 2, &left, &right) < 0) return NULL;
bool result = false;
char* end;
long l_int = strtol(left, &end, 10);
if (left[0] == '\0' || *end != '\0') {
goto done;
}
long r_int = strtol(right, &end, 10);
if (right[0] == '\0' || *end != '\0') {
goto done;
}
result = l_int < r_int;
done:
free(left);
free(right);
return StringValue(strdup(result ? "t" : ""));
}
Value* GreaterThanIntFn(const char* name, State* state,
int argc, Expr* argv[]) {
if (argc != 2) {
free(state->errmsg);
state->errmsg = strdup("greater_than_int expects 2 arguments");
return NULL;
}
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(strdup(name));
}
Expr* Build(Function fn, YYLTYPE loc, int count, ...) {
va_list v;
va_start(v, count);
Expr* e = malloc(sizeof(Expr));
e->fn = fn;
e->name = "(operator)";
e->argc = count;
e->argv = malloc(count * sizeof(Expr*));
int i;
for (i = 0; i < count; ++i) {
e->argv[i] = va_arg(v, Expr*);
}
va_end(v);
e->start = loc.start;
e->end = loc.end;
return e;
}
// -----------------------------------------------------------------
// the function table
// -----------------------------------------------------------------
static int fn_entries = 0;
static int fn_size = 0;
NamedFunction* fn_table = NULL;
void RegisterFunction(const char* name, Function fn) {
if (fn_entries >= fn_size) {
fn_size = fn_size*2 + 1;
fn_table = realloc(fn_table, fn_size * sizeof(NamedFunction));
}
fn_table[fn_entries].name = name;
fn_table[fn_entries].fn = fn;
++fn_entries;
}
static int fn_entry_compare(const void* a, const void* b) {
const char* na = ((const NamedFunction*)a)->name;
const char* nb = ((const NamedFunction*)b)->name;
return strcmp(na, nb);
}
void FinishRegistration() {
qsort(fn_table, fn_entries, sizeof(NamedFunction), fn_entry_compare);
}
Function FindFunction(const char* name) {
NamedFunction key;
key.name = name;
NamedFunction* nf = bsearch(&key, fn_table, fn_entries,
sizeof(NamedFunction), fn_entry_compare);
if (nf == NULL) {
return NULL;
}
return nf->fn;
}
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, 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 = malloc(count * sizeof(char*));
va_list v;
va_start(v, count);
int i;
for (i = 0; i < count; ++i) {
args[i] = Evaluate(state, argv[i]);
if (args[i] == NULL) {
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 = malloc(count * sizeof(Value*));
va_list v;
va_start(v, count);
int i;
for (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) {
FreeValue(args[j]);
}
free(args);
return -1;
}
*(va_arg(v, Value**)) = args[i];
}
va_end(v);
free(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*));
int i = 0;
for (i = 0; i < argc; ++i) {
args[i] = Evaluate(state, argv[i]);
if (args[i] == NULL) {
int j;
for (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 = (Value**)malloc(argc * sizeof(Value*));
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) {
FreeValue(args[j]);
}
free(args);
return NULL;
}
}
return args;
}
// Use printf-style arguments to compose an error message to put into
// *state. Returns NULL.
Value* ErrorAbort(State* state, const char* format, ...) {
char* buffer = malloc(4096);
va_list v;
va_start(v, format);
vsnprintf(buffer, 4096, format, v);
va_end(v);
free(state->errmsg);
state->errmsg = buffer;
return NULL;
}
