libdexfile/dex/descriptors_names.cc - LeafOS-Project/android_art - Gitiles

 /*
  * Copyright (C) 2011 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 "descriptors_names.h"

 #include <algorithm>

 #include "android-base/stringprintf.h"
 #include "android-base/strings.h"

 #include "base/macros.h"
 #include "dex/utf-inl.h"

 namespace art {

 using android::base::StringAppendF;

 void AppendPrettyDescriptor(const char* descriptor, std::string* result) {
   // Count the number of '['s to get the dimensionality.
   const char* c = descriptor;
   size_t dim = 0;
   while (*c == '[') {
     dim++;
     c++;
   }

   // Reference or primitive?
   bool primitive = false;
   if (*c == 'L') {
     // "[[La/b/C;" -> "a.b.C[][]".
     c++;  // Skip the 'L'.
   } else {
     primitive = true;
     // "[[B" -> "byte[][]".
     switch (*c) {
       case 'B':
         c = "byte";
         break;
       case 'C':
         c = "char";
         break;
       case 'D':
         c = "double";
         break;
       case 'F':
         c = "float";
         break;
       case 'I':
         c = "int";
         break;
       case 'J':
         c = "long";
         break;
       case 'S':
         c = "short";
         break;
       case 'Z':
         c = "boolean";
         break;
       case 'V':
         c = "void";
         break;  // Used when decoding return types.
       default: result->append(descriptor); return;
     }
   }

   // At this point, 'c' is a string of the form "fully/qualified/Type;" or
   // "primitive". In the former case, rewrite the type with '.' instead of '/':
   std::string temp(c);
   if (!primitive) {
     std::replace(temp.begin(), temp.end(), '/', '.');
     // ...and remove the semicolon:
     if (temp.back() == ';') {
       temp.pop_back();
     }
   }
   result->append(temp);

   // Finally, add 'dim' "[]" pairs:
   for (size_t i = 0; i < dim; ++i) {
     result->append("[]");
   }
 }

 std::string PrettyDescriptor(const char* descriptor) {
   std::string result;
   AppendPrettyDescriptor(descriptor, &result);
   return result;
 }

 std::string InversePrettyDescriptor(const std::string& pretty_descriptor) {
   std::string result;

   // Used to determine the length of the descriptor without trailing "[]"s.
   size_t l = pretty_descriptor.length();

   // Determine dimensionality, and append the necessary leading '['s.
   size_t dim = 0;
   size_t pos = 0;
   static const std::string array_indicator = "[]";
   while ((pos = pretty_descriptor.find(array_indicator, pos)) != std::string::npos) {
     if (dim == 0) {
       l = pos;
     }
     ++dim;
     pos += array_indicator.length();
   }
   for (size_t i = 0; i < dim; ++i) {
     result += '[';
   }

   // temp_descriptor is now in the form of "some.pretty.Type" or "primitive".
   std::string temp_descriptor(pretty_descriptor, 0, l);
   if (temp_descriptor == "byte") {
     result += 'B';
   } else if (temp_descriptor == "char") {
     result += 'C';
   } else if (temp_descriptor == "double") {
     result += 'D';
   } else if (temp_descriptor == "float") {
     result += 'F';
   } else if (temp_descriptor == "int") {
     result += 'I';
   } else if (temp_descriptor == "long") {
     result += 'J';
   } else if (temp_descriptor == "short") {
     result += 'S';
   } else if (temp_descriptor == "boolean") {
     result += 'Z';
   } else if (temp_descriptor == "void") {
     result += 'V';
   } else {
     result += 'L';
     std::replace(temp_descriptor.begin(), temp_descriptor.end(), '.', '/');
     result += temp_descriptor;
     result += ';';
   }
   return result;
 }

 std::string GetJniShortName(const std::string& class_descriptor, const std::string& method) {
   // Remove the leading 'L' and trailing ';'...
   std::string class_name(class_descriptor);
   CHECK_EQ(class_name[0], 'L') << class_name;
   CHECK_EQ(class_name[class_name.size() - 1], ';') << class_name;
   class_name.erase(0, 1);
   class_name.erase(class_name.size() - 1, 1);

   std::string short_name;
   short_name += "Java_";
   short_name += MangleForJni(class_name);
   short_name += "_";
   short_name += MangleForJni(method);
   return short_name;
 }

 // See http://java.sun.com/j2se/1.5.0/docs/guide/jni/spec/design.html#wp615 for the full rules.
 std::string MangleForJni(const std::string& s) {
   std::string result;
   size_t char_count = CountModifiedUtf8Chars(s.c_str());
   const char* cp = &s[0];
   for (size_t i = 0; i < char_count; ++i) {
     uint32_t ch = GetUtf16FromUtf8(&cp);
     if ((ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z') || (ch >= '0' && ch <= '9')) {
       result.push_back(ch);
     } else if (ch == '.' || ch == '/') {
       result += "_";
     } else if (ch == '_') {
       result += "_1";
     } else if (ch == ';') {
       result += "_2";
     } else if (ch == '[') {
       result += "_3";
     } else {
       const uint16_t leading = GetLeadingUtf16Char(ch);
       const uint32_t trailing = GetTrailingUtf16Char(ch);

       StringAppendF(&result, "_0%04x", leading);
       if (trailing != 0) {
         StringAppendF(&result, "_0%04x", trailing);
       }
     }
   }
   return result;
 }

 std::string DotToDescriptor(const char* class_name) {
   std::string descriptor(class_name);
   std::replace(descriptor.begin(), descriptor.end(), '.', '/');
   if (descriptor.length() > 0 && descriptor[0] != '[') {
     descriptor = "L" + descriptor + ";";
   }
   return descriptor;
 }

 std::string DescriptorToDot(const char* descriptor) {
   size_t length = strlen(descriptor);
   if (length > 1) {
     if (descriptor[0] == 'L' && descriptor[length - 1] == ';') {
       // Descriptors have the leading 'L' and trailing ';' stripped.
       std::string result(descriptor + 1, length - 2);
       std::replace(result.begin(), result.end(), '/', '.');
       return result;
     } else {
       // For arrays the 'L' and ';' remain intact.
       std::string result(descriptor);
       std::replace(result.begin(), result.end(), '/', '.');
       return result;
     }
   }
   // Do nothing for non-class/array descriptors.
   return descriptor;
 }

 std::string DescriptorToName(const char* descriptor) {
   size_t length = strlen(descriptor);
   if (descriptor[0] == 'L' && descriptor[length - 1] == ';') {
     std::string result(descriptor + 1, length - 2);
     return result;
   }
   return descriptor;
 }

 // Helper for IsValidPartOfMemberNameUtf8(), a bit vector indicating valid low ascii.
 static constexpr uint32_t DEX_MEMBER_VALID_LOW_ASCII[4] = {
   0x00000000,  // 00..1f low control characters; nothing valid
   0x03ff2011,  // 20..3f space, digits and symbols; valid: ' ', '0'..'9', '$', '-'
   0x87fffffe,  // 40..5f uppercase etc.; valid: 'A'..'Z', '_'
   0x07fffffe   // 60..7f lowercase etc.; valid: 'a'..'z'
 };

 // Helper for IsValidPartOfMemberNameUtf8(); do not call directly.
 COLD_ATTR
 static bool IsValidPartOfMemberNameUtf8Slow(const char** pUtf8Ptr) {
   /*
    * It's a multibyte encoded character. Decode it and analyze. We
    * accept anything that isn't:
    *   - an improperly encoded low value
    *   - an improper surrogate pair
    *   - an encoded '\0'
    *   - a C1 control character U+0080..U+009f
    *   - a format character U+200b..U+200f, U+2028..U+202e
    *   - a special character U+fff0..U+ffff
    * Prior to DEX format version 040, we also excluded some of the Unicode
    * space characters:
    *   - U+00a0, U+2000..U+200a, U+202f
    * This is all specified in the dex format document.
    */

   const uint32_t pair = GetUtf16FromUtf8(pUtf8Ptr);
   const uint16_t leading = GetLeadingUtf16Char(pair);

   // We have a surrogate pair resulting from a valid 4 byte UTF sequence.
   // No further checks are necessary because 4 byte sequences span code
   // points [U+10000, U+1FFFFF], which are valid codepoints in a dex
   // identifier. Furthermore, GetUtf16FromUtf8 guarantees that each of
   // the surrogate halves are valid and well formed in this instance.
   if (GetTrailingUtf16Char(pair) != 0) {
     return true;
   }


   // We've encountered a one, two or three byte UTF-8 sequence. The
   // three byte UTF-8 sequence could be one half of a surrogate pair.
   switch (leading >> 8) {
     case 0x00:
       // It's in the range that has C1 control characters.
       return (leading >= 0x00a0);
     case 0xd8:
     case 0xd9:
     case 0xda:
     case 0xdb:
       {
         // We found a three byte sequence encoding one half of a surrogate.
         // Look for the other half.
         const uint32_t pair2 = GetUtf16FromUtf8(pUtf8Ptr);
         const uint16_t trailing = GetLeadingUtf16Char(pair2);

         return (GetTrailingUtf16Char(pair2) == 0) && (0xdc00 <= trailing && trailing <= 0xdfff);
       }
     case 0xdc:
     case 0xdd:
     case 0xde:
     case 0xdf:
       // It's a trailing surrogate, which is not valid at this point.
       return false;
     case 0x20:
     case 0xff:
       // It's in the range that has format characters and specials.
       switch (leading & 0xfff8) {
         case 0x2008:
           return (leading <= 0x200a);
         case 0x2028:
           return (leading == 0x202f);
         case 0xfff0:
         case 0xfff8:
           return false;
       }
       return true;
     default:
       return true;
   }

   UNREACHABLE();
 }

 /* Return whether the pointed-at modified-UTF-8 encoded character is
  * valid as part of a member name, updating the pointer to point past
  * the consumed character. This will consume two encoded UTF-16 code
  * points if the character is encoded as a surrogate pair. Also, if
  * this function returns false, then the given pointer may only have
  * been partially advanced.
  */
 ALWAYS_INLINE
 static bool IsValidPartOfMemberNameUtf8(const char** pUtf8Ptr) {
   uint8_t c = (uint8_t) **pUtf8Ptr;
   if (LIKELY(c <= 0x7f)) {
     // It's low-ascii, so check the table.
     uint32_t wordIdx = c >> 5;
     uint32_t bitIdx = c & 0x1f;
     (*pUtf8Ptr)++;
     return (DEX_MEMBER_VALID_LOW_ASCII[wordIdx] & (1 << bitIdx)) != 0;
   }

   // It's a multibyte encoded character. Call a non-inline function
   // for the heavy lifting.
   return IsValidPartOfMemberNameUtf8Slow(pUtf8Ptr);
 }

 bool IsValidMemberName(const char* s) {
   bool angle_name = false;

   switch (*s) {
     case '\0':
       // The empty string is not a valid name.
       return false;
     case '<':
       angle_name = true;
       s++;
       break;
   }

   while (true) {
     switch (*s) {
       case '\0':
         return !angle_name;
       case '>':
         return angle_name && s[1] == '\0';
     }

     if (!IsValidPartOfMemberNameUtf8(&s)) {
       return false;
     }
   }
 }

 enum ClassNameType { kName, kDescriptor };
 template<ClassNameType kType, char kSeparator>
 static bool IsValidClassName(const char* s) {
   int arrayCount = 0;
   while (*s == '[') {
     arrayCount++;
     s++;
   }

   if (arrayCount > 255) {
     // Arrays may have no more than 255 dimensions.
     return false;
   }

   ClassNameType type = kType;
   if (type != kDescriptor && arrayCount != 0) {
     /*
      * If we're looking at an array of some sort, then it doesn't
      * matter if what is being asked for is a class name; the
      * format looks the same as a type descriptor in that case, so
      * treat it as such.
      */
     type = kDescriptor;
   }

   if (type == kDescriptor) {
     /*
      * We are looking for a descriptor. Either validate it as a
      * single-character primitive type, or continue on to check the
      * embedded class name (bracketed by "L" and ";").
      */
     switch (*(s++)) {
     case 'B':
     case 'C':
     case 'D':
     case 'F':
     case 'I':
     case 'J':
     case 'S':
     case 'Z':
       // These are all single-character descriptors for primitive types.
       return (*s == '\0');
     case 'V':
       // Non-array void is valid, but you can't have an array of void.
       return (arrayCount == 0) && (*s == '\0');
     case 'L':
       // Class name: Break out and continue below.
       break;
     default:
       // Oddball descriptor character.
       return false;
     }
   }

   /*
    * We just consumed the 'L' that introduces a class name as part
    * of a type descriptor, or we are looking for an unadorned class
    * name.
    */

   bool sepOrFirst = true;  // first character or just encountered a separator.
   for (;;) {
     uint8_t c = (uint8_t) *s;
     switch (c) {
     case '\0':
       /*
        * Premature end for a type descriptor, but valid for
        * a class name as long as we haven't encountered an
        * empty component (including the degenerate case of
        * the empty string "").
        */
       return (type == kName) && !sepOrFirst;
     case ';':
       /*
        * Invalid character for a class name, but the
        * legitimate end of a type descriptor. In the latter
        * case, make sure that this is the end of the string
        * and that it doesn't end with an empty component
        * (including the degenerate case of "L;").
        */
       return (type == kDescriptor) && !sepOrFirst && (s[1] == '\0');
     case '/':
     case '.':
       if (c != kSeparator) {
         // The wrong separator character.
         return false;
       }
       if (sepOrFirst) {
         // Separator at start or two separators in a row.
         return false;
       }
       sepOrFirst = true;
       s++;
       break;
     default:
       if (!IsValidPartOfMemberNameUtf8(&s)) {
         return false;
       }
       sepOrFirst = false;
       break;
     }
   }
 }

 bool IsValidBinaryClassName(const char* s) {
   return IsValidClassName<kName, '.'>(s);
 }

 bool IsValidJniClassName(const char* s) {
   return IsValidClassName<kName, '/'>(s);
 }

 bool IsValidDescriptor(const char* s) {
   return IsValidClassName<kDescriptor, '/'>(s);
 }

 std::string PrettyDescriptor(Primitive::Type type) {
   return PrettyDescriptor(Primitive::Descriptor(type));
 }

 }  // namespace art
	/*
	* Copyright (C) 2011 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 "descriptors_names.h"

	#include <algorithm>

	#include "android-base/stringprintf.h"
	#include "android-base/strings.h"

	#include "base/macros.h"
	#include "dex/utf-inl.h"

	namespace art {

	using android::base::StringAppendF;

	void AppendPrettyDescriptor(const char* descriptor, std::string* result) {
	// Count the number of '['s to get the dimensionality.
	const char* c = descriptor;
	size_t dim = 0;
	while (*c == '[') {
	dim++;
	c++;
	}

	// Reference or primitive?
	bool primitive = false;
	if (*c == 'L') {
	// "[[La/b/C;" -> "a.b.C[][]".
	c++; // Skip the 'L'.
	} else {
	primitive = true;
	// "[[B" -> "byte[][]".
	switch (*c) {
	case 'B':
	c = "byte";
	break;
	case 'C':
	c = "char";
	break;
	case 'D':
	c = "double";
	break;
	case 'F':
	c = "float";
	break;
	case 'I':
	c = "int";
	break;
	case 'J':
	c = "long";
	break;
	case 'S':
	c = "short";
	break;
	case 'Z':
	c = "boolean";
	break;
	case 'V':
	c = "void";
	break; // Used when decoding return types.
	default: result->append(descriptor); return;
	}
	}

	// At this point, 'c' is a string of the form "fully/qualified/Type;" or
	// "primitive". In the former case, rewrite the type with '.' instead of '/':
	std::string temp(c);
	if (!primitive) {
	std::replace(temp.begin(), temp.end(), '/', '.');
	// ...and remove the semicolon:
	if (temp.back() == ';') {
	temp.pop_back();
	}
	}
	result->append(temp);

	// Finally, add 'dim' "[]" pairs:
	for (size_t i = 0; i < dim; ++i) {
	result->append("[]");
	}
	}

	std::string PrettyDescriptor(const char* descriptor) {
	std::string result;
	AppendPrettyDescriptor(descriptor, &result);
	return result;
	}

	std::string InversePrettyDescriptor(const std::string& pretty_descriptor) {
	std::string result;

	// Used to determine the length of the descriptor without trailing "[]"s.
	size_t l = pretty_descriptor.length();

	// Determine dimensionality, and append the necessary leading '['s.
	size_t dim = 0;
	size_t pos = 0;
	static const std::string array_indicator = "[]";
	while ((pos = pretty_descriptor.find(array_indicator, pos)) != std::string::npos) {
	if (dim == 0) {
	l = pos;
	}
	++dim;
	pos += array_indicator.length();
	}
	for (size_t i = 0; i < dim; ++i) {
	result += '[';
	}

	// temp_descriptor is now in the form of "some.pretty.Type" or "primitive".
	std::string temp_descriptor(pretty_descriptor, 0, l);
	if (temp_descriptor == "byte") {
	result += 'B';
	} else if (temp_descriptor == "char") {
	result += 'C';
	} else if (temp_descriptor == "double") {
	result += 'D';
	} else if (temp_descriptor == "float") {
	result += 'F';
	} else if (temp_descriptor == "int") {
	result += 'I';
	} else if (temp_descriptor == "long") {
	result += 'J';
	} else if (temp_descriptor == "short") {
	result += 'S';
	} else if (temp_descriptor == "boolean") {
	result += 'Z';
	} else if (temp_descriptor == "void") {
	result += 'V';
	} else {
	result += 'L';
	std::replace(temp_descriptor.begin(), temp_descriptor.end(), '.', '/');
	result += temp_descriptor;
	result += ';';
	}
	return result;
	}

	std::string GetJniShortName(const std::string& class_descriptor, const std::string& method) {
	// Remove the leading 'L' and trailing ';'...
	std::string class_name(class_descriptor);
	CHECK_EQ(class_name[0], 'L') << class_name;
	CHECK_EQ(class_name[class_name.size() - 1], ';') << class_name;
	class_name.erase(0, 1);
	class_name.erase(class_name.size() - 1, 1);

	std::string short_name;
	short_name += "Java_";
	short_name += MangleForJni(class_name);
	short_name += "_";
	short_name += MangleForJni(method);
	return short_name;
	}

	// See http://java.sun.com/j2se/1.5.0/docs/guide/jni/spec/design.html#wp615 for the full rules.
	std::string MangleForJni(const std::string& s) {
	std::string result;
	size_t char_count = CountModifiedUtf8Chars(s.c_str());
	const char* cp = &s[0];
	for (size_t i = 0; i < char_count; ++i) {
	uint32_t ch = GetUtf16FromUtf8(&cp);
	if ((ch >= 'A' && ch <= 'Z') \|\| (ch >= 'a' && ch <= 'z') \|\| (ch >= '0' && ch <= '9')) {
	result.push_back(ch);
	} else if (ch == '.' \|\| ch == '/') {
	result += "_";
	} else if (ch == '_') {
	result += "_1";
	} else if (ch == ';') {
	result += "_2";
	} else if (ch == '[') {
	result += "_3";
	} else {
	const uint16_t leading = GetLeadingUtf16Char(ch);
	const uint32_t trailing = GetTrailingUtf16Char(ch);

	StringAppendF(&result, "_0%04x", leading);
	if (trailing != 0) {
	StringAppendF(&result, "_0%04x", trailing);
	}
	}
	}
	return result;
	}

	std::string DotToDescriptor(const char* class_name) {
	std::string descriptor(class_name);
	std::replace(descriptor.begin(), descriptor.end(), '.', '/');
	if (descriptor.length() > 0 && descriptor[0] != '[') {
	descriptor = "L" + descriptor + ";";
	}
	return descriptor;
	}

	std::string DescriptorToDot(const char* descriptor) {
	size_t length = strlen(descriptor);
	if (length > 1) {
	if (descriptor[0] == 'L' && descriptor[length - 1] == ';') {
	// Descriptors have the leading 'L' and trailing ';' stripped.
	std::string result(descriptor + 1, length - 2);
	std::replace(result.begin(), result.end(), '/', '.');
	return result;
	} else {
	// For arrays the 'L' and ';' remain intact.
	std::string result(descriptor);
	std::replace(result.begin(), result.end(), '/', '.');
	return result;
	}
	}
	// Do nothing for non-class/array descriptors.
	return descriptor;
	}

	std::string DescriptorToName(const char* descriptor) {
	size_t length = strlen(descriptor);
	if (descriptor[0] == 'L' && descriptor[length - 1] == ';') {
	std::string result(descriptor + 1, length - 2);
	return result;
	}
	return descriptor;
	}

	// Helper for IsValidPartOfMemberNameUtf8(), a bit vector indicating valid low ascii.
	static constexpr uint32_t DEX_MEMBER_VALID_LOW_ASCII[4] = {
	0x00000000, // 00..1f low control characters; nothing valid
	0x03ff2011, // 20..3f space, digits and symbols; valid: ' ', '0'..'9', '$', '-'
	0x87fffffe, // 40..5f uppercase etc.; valid: 'A'..'Z', '_'
	0x07fffffe // 60..7f lowercase etc.; valid: 'a'..'z'
	};

	// Helper for IsValidPartOfMemberNameUtf8(); do not call directly.
	COLD_ATTR
	static bool IsValidPartOfMemberNameUtf8Slow(const char** pUtf8Ptr) {
	/*
	* It's a multibyte encoded character. Decode it and analyze. We
	* accept anything that isn't:
	* - an improperly encoded low value
	* - an improper surrogate pair
	* - an encoded '\0'
	* - a C1 control character U+0080..U+009f
	* - a format character U+200b..U+200f, U+2028..U+202e
	* - a special character U+fff0..U+ffff
	* Prior to DEX format version 040, we also excluded some of the Unicode
	* space characters:
	* - U+00a0, U+2000..U+200a, U+202f
	* This is all specified in the dex format document.
	*/

	const uint32_t pair = GetUtf16FromUtf8(pUtf8Ptr);
	const uint16_t leading = GetLeadingUtf16Char(pair);

	// We have a surrogate pair resulting from a valid 4 byte UTF sequence.
	// No further checks are necessary because 4 byte sequences span code
	// points [U+10000, U+1FFFFF], which are valid codepoints in a dex
	// identifier. Furthermore, GetUtf16FromUtf8 guarantees that each of
	// the surrogate halves are valid and well formed in this instance.
	if (GetTrailingUtf16Char(pair) != 0) {
	return true;
	}


	// We've encountered a one, two or three byte UTF-8 sequence. The
	// three byte UTF-8 sequence could be one half of a surrogate pair.
	switch (leading >> 8) {
	case 0x00:
	// It's in the range that has C1 control characters.
	return (leading >= 0x00a0);
	case 0xd8:
	case 0xd9:
	case 0xda:
	case 0xdb:
	{
	// We found a three byte sequence encoding one half of a surrogate.
	// Look for the other half.
	const uint32_t pair2 = GetUtf16FromUtf8(pUtf8Ptr);
	const uint16_t trailing = GetLeadingUtf16Char(pair2);

	return (GetTrailingUtf16Char(pair2) == 0) && (0xdc00 <= trailing && trailing <= 0xdfff);
	}
	case 0xdc:
	case 0xdd:
	case 0xde:
	case 0xdf:
	// It's a trailing surrogate, which is not valid at this point.
	return false;
	case 0x20:
	case 0xff:
	// It's in the range that has format characters and specials.
	switch (leading & 0xfff8) {
	case 0x2008:
	return (leading <= 0x200a);
	case 0x2028:
	return (leading == 0x202f);
	case 0xfff0:
	case 0xfff8:
	return false;
	}
	return true;
	default:
	return true;
	}

	UNREACHABLE();
	}

	/* Return whether the pointed-at modified-UTF-8 encoded character is
	* valid as part of a member name, updating the pointer to point past
	* the consumed character. This will consume two encoded UTF-16 code
	* points if the character is encoded as a surrogate pair. Also, if
	* this function returns false, then the given pointer may only have
	* been partially advanced.
	*/
	ALWAYS_INLINE
	static bool IsValidPartOfMemberNameUtf8(const char** pUtf8Ptr) {
	uint8_t c = (uint8_t) **pUtf8Ptr;
	if (LIKELY(c <= 0x7f)) {
	// It's low-ascii, so check the table.
	uint32_t wordIdx = c >> 5;
	uint32_t bitIdx = c & 0x1f;
	(*pUtf8Ptr)++;
	return (DEX_MEMBER_VALID_LOW_ASCII[wordIdx] & (1 << bitIdx)) != 0;
	}

	// It's a multibyte encoded character. Call a non-inline function
	// for the heavy lifting.
	return IsValidPartOfMemberNameUtf8Slow(pUtf8Ptr);
	}

	bool IsValidMemberName(const char* s) {
	bool angle_name = false;

	switch (*s) {
	case '\0':
	// The empty string is not a valid name.
	return false;
	case '<':
	angle_name = true;
	s++;
	break;
	}

	while (true) {
	switch (*s) {
	case '\0':
	return !angle_name;
	case '>':
	return angle_name && s[1] == '\0';
	}

	if (!IsValidPartOfMemberNameUtf8(&s)) {
	return false;
	}
	}
	}

	enum ClassNameType { kName, kDescriptor };
	template<ClassNameType kType, char kSeparator>
	static bool IsValidClassName(const char* s) {
	int arrayCount = 0;
	while (*s == '[') {
	arrayCount++;
	s++;
	}

	if (arrayCount > 255) {
	// Arrays may have no more than 255 dimensions.
	return false;
	}

	ClassNameType type = kType;
	if (type != kDescriptor && arrayCount != 0) {
	/*
	* If we're looking at an array of some sort, then it doesn't
	* matter if what is being asked for is a class name; the
	* format looks the same as a type descriptor in that case, so
	* treat it as such.
	*/
	type = kDescriptor;
	}

	if (type == kDescriptor) {
	/*
	* We are looking for a descriptor. Either validate it as a
	* single-character primitive type, or continue on to check the
	* embedded class name (bracketed by "L" and ";").
	*/
	switch (*(s++)) {
	case 'B':
	case 'C':
	case 'D':
	case 'F':
	case 'I':
	case 'J':
	case 'S':
	case 'Z':
	// These are all single-character descriptors for primitive types.
	return (*s == '\0');
	case 'V':
	// Non-array void is valid, but you can't have an array of void.
	return (arrayCount == 0) && (*s == '\0');
	case 'L':
	// Class name: Break out and continue below.
	break;
	default:
	// Oddball descriptor character.
	return false;
	}
	}

	/*
	* We just consumed the 'L' that introduces a class name as part
	* of a type descriptor, or we are looking for an unadorned class
	* name.
	*/

	bool sepOrFirst = true; // first character or just encountered a separator.
	for (;;) {
	uint8_t c = (uint8_t) *s;
	switch (c) {
	case '\0':
	/*
	* Premature end for a type descriptor, but valid for
	* a class name as long as we haven't encountered an
	* empty component (including the degenerate case of
	* the empty string "").
	*/
	return (type == kName) && !sepOrFirst;
	case ';':
	/*
	* Invalid character for a class name, but the
	* legitimate end of a type descriptor. In the latter
	* case, make sure that this is the end of the string
	* and that it doesn't end with an empty component
	* (including the degenerate case of "L;").
	*/
	return (type == kDescriptor) && !sepOrFirst && (s[1] == '\0');
	case '/':
	case '.':
	if (c != kSeparator) {
	// The wrong separator character.
	return false;
	}
	if (sepOrFirst) {
	// Separator at start or two separators in a row.
	return false;
	}
	sepOrFirst = true;
	s++;
	break;
	default:
	if (!IsValidPartOfMemberNameUtf8(&s)) {
	return false;
	}
	sepOrFirst = false;
	break;
	}
	}
	}

	bool IsValidBinaryClassName(const char* s) {
	return IsValidClassName<kName, '.'>(s);
	}

	bool IsValidJniClassName(const char* s) {
	return IsValidClassName<kName, '/'>(s);
	}

	bool IsValidDescriptor(const char* s) {
	return IsValidClassName<kDescriptor, '/'>(s);
	}

	std::string PrettyDescriptor(Primitive::Type type) {
	return PrettyDescriptor(Primitive::Descriptor(type));
	}

	} // namespace art