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author | Tao Bao <tbao@google.com> | 2015-08-21 20:31:29 +0200 |
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committer | Android Git Automerger <android-git-automerger@android.com> | 2015-08-21 20:31:29 +0200 |
commit | 459a51739d9c3f9699193965e3cf11968ae3a20f (patch) | |
tree | 77158f2bcd0f4f814667390954cde6c160417110 /edify/expr.cpp | |
parent | am e57ca0ec: am 4854e292: am ad509fd4: Merge "Fix potential crash" (diff) | |
parent | am dbbdcf3f: am 93fa4b67: Merge "edify: Switch to C++." (diff) | |
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Diffstat (limited to 'edify/expr.cpp')
-rw-r--r-- | edify/expr.cpp | 507 |
1 files changed, 507 insertions, 0 deletions
diff --git a/edify/expr.cpp b/edify/expr.cpp new file mode 100644 index 000000000..cd1e08726 --- /dev/null +++ b/edify/expr.cpp @@ -0,0 +1,507 @@ +/* + * 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 = reinterpret_cast<Value*>(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 = reinterpret_cast<char**>(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 = reinterpret_cast<char*>(malloc(length+1)); + int p; + 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 = reinterpret_cast<char*>(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; + 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 = reinterpret_cast<Expr*>(malloc(sizeof(Expr))); + e->fn = fn; + e->name = "(operator)"; + e->argc = count; + e->argv = reinterpret_cast<Expr**>(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 = reinterpret_cast<NamedFunction*>(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 = reinterpret_cast<NamedFunction*>(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 = reinterpret_cast<char**>(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 = reinterpret_cast<Value**>(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 = reinterpret_cast<char*>(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; +} |