/*
* 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 "android-base/stringprintf.h"
#include "android-base/strings.h"
#include "dex/utf-inl.h"
namespace art {
using android::base::StringAppendF;
using android::base::StringPrintf;
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?
if (*c == 'L') {
// "[[La/b/C;" -> "a.b.C[][]".
c++; // Skip the 'L'.
} else {
// "[[B" -> "byte[][]".
// To make life easier, we make primitives look like unqualified
// reference types.
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;". Rewrite the type with '.' instead of '/':
const char* p = c;
while (*p != ';') {
char ch = *p++;
if (ch == '/') {
ch = '.';
}
result->push_back(ch);
}
// ...and replace the semicolon with '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 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 uint32_t DEX_MEMBER_VALID_LOW_ASCII[4] = {
0x00000000, // 00..1f low control characters; nothing valid
0x03ff2010, // 20..3f 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.
static bool IsValidPartOfMemberNameUtf8Slow(const char** pUtf8Ptr) {
/*
* It's a multibyte encoded character. Decode it and analyze. We
* accept anything that isn't (a) an improperly encoded low value,
* (b) an improper surrogate pair, (c) an encoded '\0', (d) a high
* control character, or (e) a high space, layout, or special
* character (U+00a0, U+2000..U+200f, U+2028..U+202f,
* U+fff0..U+ffff). 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 only valid if it's above the ISO-8859-1 high space (0xa0).
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 spaces, controls, and specials.
switch (leading & 0xfff8) {
case 0x2000:
case 0x2008:
case 0x2028:
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.
*/
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);
}
void Split(const std::string& s, char separator, std::vector<std::string>* result) {
const char* p = s.data();
const char* end = p + s.size();
while (p != end) {
if (*p == separator) {
++p;
} else {
const char* start = p;
while (++p != end && *p != separator) {
// Skip to the next occurrence of the separator.
}
result->push_back(std::string(start, p - start));
}
}
}
std::string PrettyDescriptor(Primitive::Type type) {
return PrettyDescriptor(Primitive::Descriptor(type));
}
} // namespace art