Revert "Add automatic default value for char-type field" am: ac1cb3eb26

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/tools/aidl/+/16381822

Change-Id: Id9836b91b75c4c46461b0a2c43a4410a5f447480

5 files changed, 31 insertions, 31 deletions

diff --git a/aidl_const_expressions.cpp b/aidl_const_expressions.cpp
index b9b62ea6..b97889d6 100644
--- a/aidl_const_expressions.cpp
+++ b/aidl_const_expressions.cpp
@@ -242,6 +242,12 @@ bool handleLogical(const AidlConstantValue& context, bool lval, const string& op
   return false;
 }
 
+static bool isValidLiteralChar(char c) {
+  return !(c <= 0x1f ||  // control characters are < 0x20
+           c >= 0x7f ||  // DEL is 0x7f
+           c == '\\');   // Disallow backslashes for future proofing.
+}
+
 bool ParseFloating(std::string_view sv, double* parsed) {
   // float literal should be parsed successfully.
   android::base::ConsumeSuffix(&sv, "f");
@@ -332,9 +338,6 @@ AidlConstantValue* AidlConstantValue::Default(const AidlTypeSpecifier& specifier
   if (name == "boolean") {
     return Boolean(location, false);
   }
-  if (name == "char") {
-    return Character(location, "'\\0'");  // literal to be used in backends
-  }
   if (name == "byte" || name == "int" || name == "long") {
     return Integral(location, "0");
   }
@@ -351,9 +354,13 @@ AidlConstantValue* AidlConstantValue::Boolean(const AidlLocation& location, bool
   return new AidlConstantValue(location, Type::BOOLEAN, value ? "true" : "false");
 }
 
-AidlConstantValue* AidlConstantValue::Character(const AidlLocation& location,
-                                                const std::string& value) {
-  return new AidlConstantValue(location, Type::CHARACTER, value);
+AidlConstantValue* AidlConstantValue::Character(const AidlLocation& location, char value) {
+  const std::string explicit_value = string("'") + value + "'";
+  if (!isValidLiteralChar(value)) {
+    AIDL_ERROR(location) << "Invalid character literal " << value;
+    return new AidlConstantValue(location, Type::ERROR, explicit_value);
+  }
+  return new AidlConstantValue(location, Type::CHARACTER, explicit_value);
 }
 
 AidlConstantValue* AidlConstantValue::Floating(const AidlLocation& location,
@@ -446,6 +453,14 @@ AidlConstantValue* AidlConstantValue::Array(
 }
 
 AidlConstantValue* AidlConstantValue::String(const AidlLocation& location, const string& value) {
+  for (size_t i = 0; i < value.length(); ++i) {
+    if (!isValidLiteralChar(value[i])) {
+      AIDL_ERROR(location) << "Found invalid character at index " << i << " in string constant '"
+                           << value << "'";
+      return new AidlConstantValue(location, Type::ERROR, value);
+    }
+  }
+
   return new AidlConstantValue(location, Type::STRING, value);
 }
 
@@ -992,8 +1007,6 @@ bool AidlBinaryConstExpression::evaluate() const {
   return false;
 }
 
-// Constructor for integer(byte, int, long)
-// Keep parsed integer & literal
 AidlConstantValue::AidlConstantValue(const AidlLocation& location, Type parsed_type,
                                      int64_t parsed_value, const string& checked_value)
     : AidlNode(location),
@@ -1005,8 +1018,6 @@ AidlConstantValue::AidlConstantValue(const AidlLocation& location, Type parsed_t
   AIDL_FATAL_IF(type_ != Type::INT8 && type_ != Type::INT32 && type_ != Type::INT64, location);
 }
 
-// Constructor for non-integer(String, char, boolean, float, double)
-// Keep literal as it is. (e.g. String literal has double quotes at both ends)
 AidlConstantValue::AidlConstantValue(const AidlLocation& location, Type type,
                                      const string& checked_value)
     : AidlNode(location),
@@ -1026,7 +1037,6 @@ AidlConstantValue::AidlConstantValue(const AidlLocation& location, Type type,
   }
 }
 
-// Constructor for array
 AidlConstantValue::AidlConstantValue(const AidlLocation& location, Type type,
                                      std::unique_ptr<vector<unique_ptr<AidlConstantValue>>> values,
                                      const std::string& value)
diff --git a/aidl_language.h b/aidl_language.h
index 36c50664..4e0f587d 100644
--- a/aidl_language.h
+++ b/aidl_language.h
@@ -610,7 +610,7 @@ class AidlConstantValue : public AidlNode {
     } else if constexpr (is_one_of<T, int8_t, int32_t, int64_t>::value) {
       AIDL_FATAL_IF(final_type_ < Type::INT8 && final_type_ > Type::INT64, this);
       return static_cast<T>(final_value_);
-    } else if constexpr (std::is_same<T, char16_t>::value) {
+    } else if constexpr (std::is_same<T, char>::value) {
       AIDL_FATAL_IF(final_type_ != Type::CHARACTER, this);
       return final_string_value_.at(1);  // unquote '
     } else if constexpr (std::is_same<T, bool>::value) {
@@ -635,9 +635,9 @@ class AidlConstantValue : public AidlNode {
   static AidlConstantValue* Default(const AidlTypeSpecifier& specifier);
 
   static AidlConstantValue* Boolean(const AidlLocation& location, bool value);
-  static AidlConstantValue* Character(const AidlLocation& location, const std::string& value);
+  static AidlConstantValue* Character(const AidlLocation& location, char value);
   // example: 123, -5498, maybe any size
-  static AidlConstantValue* Integral(const AidlLocation& location, const std::string& value);
+  static AidlConstantValue* Integral(const AidlLocation& location, const string& value);
   static AidlConstantValue* Floating(const AidlLocation& location, const std::string& value);
   static AidlConstantValue* Array(const AidlLocation& location,
                                   std::unique_ptr<vector<unique_ptr<AidlConstantValue>>> values);
diff --git a/aidl_language_l.ll b/aidl_language_l.ll
index 2b63b822..e43ef452 100644
--- a/aidl_language_l.ll
+++ b/aidl_language_l.ll
@@ -142,8 +142,9 @@ union                 { yylval->token = new AidlToken("union", comments);
 {identifier}          { yylval->token = new AidlToken(yytext, comments);
                         return yy::parser::token::IDENTIFIER;
                       }
-'.'                   { yylval->token = new AidlToken(yytext, comments);
-                        return yy::parser::token::CHARVALUE; }
+'.'                   { yylval->character = yytext[1];
+                        return yy::parser::token::CHARVALUE;
+                      }
 {intvalue}            { yylval->token = new AidlToken(yytext, comments);
                         return yy::parser::token::INTVALUE; }
 {floatvalue}          { yylval->token = new AidlToken(yytext, comments);
diff --git a/aidl_language_y.yy b/aidl_language_y.yy
index 079bda67..ab3e4799 100644
--- a/aidl_language_y.yy
+++ b/aidl_language_y.yy
@@ -96,6 +96,7 @@ AidlLocation loc(const yy::parser::location_type& l) {
     std::vector<std::unique_ptr<AidlDefinedType>>* declarations;
 }
 
+%destructor { } <character>
 %destructor { } <direction>
 %destructor { delete ($$); } <*>
 
@@ -111,7 +112,7 @@ AidlLocation loc(const yy::parser::location_type& l) {
 %token<token> UNION "union"
 %token<token> CONST "const"
 
-%token<token> CHARVALUE "char literal"
+%token<character> CHARVALUE "char literal"
 %token<token> FLOATVALUE "float literal"
 %token<token> HEXVALUE "hex literal"
 %token<token> INTVALUE "int literal"
@@ -394,10 +395,7 @@ interface_members
 const_expr
  : TRUE_LITERAL { $$ = AidlConstantValue::Boolean(loc(@1), true); }
  | FALSE_LITERAL { $$ = AidlConstantValue::Boolean(loc(@1), false); }
- | CHARVALUE {
-    $$ = AidlConstantValue::Character(loc(@1), $1->GetText());
-    delete $1;
-  }
+ | CHARVALUE { $$ = AidlConstantValue::Character(loc(@1), $1); }
  | INTVALUE {
     $$ = AidlConstantValue::Integral(loc(@1), $1->GetText());
     if ($$ == nullptr) {
diff --git a/aidl_unittest.cpp b/aidl_unittest.cpp
index f825cfd2..7ea8c171 100644
--- a/aidl_unittest.cpp
+++ b/aidl_unittest.cpp
@@ -32,7 +32,6 @@
 #include "aidl_language.h"
 #include "aidl_to_cpp.h"
 #include "aidl_to_java.h"
-#include "aidl_to_ndk.h"
 #include "comments.h"
 #include "logging.h"
 #include "options.h"
@@ -1026,7 +1025,7 @@ TEST_F(AidlTest, AidlConstantValue_EvaluatedValue) {
   using Ptr = unique_ptr<AidlConstantValue>;
   const AidlLocation& loc = AIDL_LOCATION_HERE;
 
-  EXPECT_EQ('c', Ptr(AidlConstantValue::Character(loc, "'c'"))->EvaluatedValue<char16_t>());
+  EXPECT_EQ('c', Ptr(AidlConstantValue::Character(loc, 'c'))->EvaluatedValue<char>());
   EXPECT_EQ("abc", Ptr(AidlConstantValue::String(loc, "\"abc\""))->EvaluatedValue<string>());
   EXPECT_FLOAT_EQ(1.0f, Ptr(AidlConstantValue::Floating(loc, "1.0f"))->EvaluatedValue<float>());
   EXPECT_EQ(true, Ptr(AidlConstantValue::Boolean(loc, true))->EvaluatedValue<bool>());
@@ -1044,14 +1043,6 @@ TEST_F(AidlTest, AidlConstantValue_EvaluatedValue) {
       Ptr(AidlConstantValue::Array(loc, std::move(values)))->EvaluatedValue<vector<string>>());
 }
 
-TEST_F(AidlTest, AidlConstantCharacterDefault) {
-  AidlTypeSpecifier char_type(AIDL_LOCATION_HERE, "char", false, nullptr, {});
-  auto default_value = unique_ptr<AidlConstantValue>(AidlConstantValue::Default(char_type));
-  EXPECT_EQ("'\\0'", default_value->ValueString(char_type, cpp::ConstantValueDecorator));
-  EXPECT_EQ("'\\0'", default_value->ValueString(char_type, ndk::ConstantValueDecorator));
-  EXPECT_EQ("'\\0'", default_value->ValueString(char_type, java::ConstantValueDecorator));
-}
-
 TEST_P(AidlTest, FailOnManyDefinedTypes) {
   AidlError error;
   const string expected_stderr =