1 /*
   2  * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/systemDictionary.hpp"
  27 #include "memory/oopFactory.hpp"
  28 #include "memory/resourceArea.hpp"
  29 #include "oops/oop.inline.hpp"
  30 #include "oops/typeArrayKlass.hpp"
  31 #include "runtime/fieldType.hpp"
  32 #include "runtime/signature.hpp"
  33 
  34 void FieldType::skip_optional_size(Symbol* signature, int* index) {
  35   jchar c = signature->byte_at(*index);
  36   while (c >= '0' && c <= '9') {
  37     *index = *index + 1;
  38     c = signature->byte_at(*index);
  39   }
  40 }
  41 
  42 BasicType FieldType::basic_type(Symbol* signature) {
  43   return char2type(signature->byte_at(0));
  44 }
  45 
  46 // Check if it is a valid array signature
  47 bool FieldType::is_valid_array_signature(Symbol* sig) {
  48   assert(sig->utf8_length() > 1, "this should already have been checked");
  49   assert(sig->byte_at(0) == '[', "this should already have been checked");
  50   // The first character is already checked
  51   int i = 1;
  52   int len = sig->utf8_length();
  53   // First skip all '['s
  54   while(i < len - 1 && sig->byte_at(i) == '[') i++;
  55 
  56   // Check type
  57   switch(sig->byte_at(i)) {
  58     case 'B': // T_BYTE
  59     case 'C': // T_CHAR
  60     case 'D': // T_DOUBLE
  61     case 'F': // T_FLOAT
  62     case 'I': // T_INT
  63     case 'J': // T_LONG
  64     case 'S': // T_SHORT
  65     case 'Z': // T_BOOLEAN
  66       // If it is an array, the type is the last character
  67       return (i + 1 == len);
  68     case 'L':
  69     case 'Q':
  70       // If it is an object or a value type, the last character must be a ';'
  71       return sig->byte_at(len - 1) == ';';
  72   }
  73 
  74   return false;
  75 }
  76 
  77 static const char dvt_postfix[] = "$Value";
  78 static const int dvt_postfix_len = 6;
  79 
  80 bool FieldType::is_dvt_postfix(Symbol* signature) {
  81   assert(strlen(dvt_postfix) == dvt_postfix_len, "Invariant");
  82   int sig_length = signature->utf8_length();
  83   int pos = sig_length - dvt_postfix_len;
  84   if (pos <= 0) {
  85     return false;
  86   }
  87   for (int i = 0; i < dvt_postfix_len; i++) {
  88     if (signature->byte_at(pos) != dvt_postfix[i]) {
  89       return false;
  90     }
  91     pos++;
  92   }
  93   return true;
  94 }
  95 
  96 char* FieldType::dvt_unmangle_vcc(Symbol* signature) {
  97   assert(is_dvt_postfix(signature), "Unmangle that which is not managled");
  98   char* str = signature->as_C_string();
  99   str[signature->utf8_length() -dvt_postfix_len] = '\0';
 100   return str;
 101 }
 102 
 103 BasicType FieldType::get_array_info(Symbol* signature, FieldArrayInfo& fd, TRAPS) {
 104   assert(basic_type(signature) == T_ARRAY, "must be array");
 105   int index = 1;
 106   int dim   = 1;
 107   skip_optional_size(signature, &index);
 108   while (signature->byte_at(index) == '[') {
 109     index++;
 110     dim++;
 111     skip_optional_size(signature, &index);
 112   }
 113   ResourceMark rm;
 114   char *element = signature->as_C_string() + index;
 115   BasicType element_type = char2type(element[0]);
 116   if (element_type == T_OBJECT || element_type == T_VALUETYPE) {
 117     int len = (int)strlen(element);
 118     assert(element[len-1] == ';', "last char should be a semicolon");
 119     element[len-1] = '\0';        // chop off semicolon
 120     fd._object_key = SymbolTable::new_symbol(element + 1, CHECK_(T_BYTE));
 121   }
 122   // Pass dimension back to caller
 123   fd._dimension = dim;
 124   return element_type;
 125 }