diff options
Diffstat (limited to 'libraries/classparser/src/constants.h')
| -rw-r--r-- | libraries/classparser/src/constants.h | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/libraries/classparser/src/constants.h b/libraries/classparser/src/constants.h new file mode 100644 index 00000000..242b943e --- /dev/null +++ b/libraries/classparser/src/constants.h @@ -0,0 +1,220 @@ +#pragma once +#include "errors.h" +#include <sstream> + +namespace java +{ +class constant +{ +public: + enum type_t : uint8_t + { + j_hole = 0, // HACK: this is a hole in the array, because java is crazy + j_string_data = 1, + j_int = 3, + j_float = 4, + j_long = 5, + j_double = 6, + j_class = 7, + j_string = 8, + j_fieldref = 9, + j_methodref = 10, + j_interface_methodref = 11, + j_nameandtype = 12 + } type; + + constant(util::membuffer &buf) + { + buf.read(type); + // invalid constant type! + if (type > j_nameandtype || type == (type_t)0 || type == (type_t)2) + throw new classfile_exception(); + + // load data depending on type + switch (type) + { + case j_float: + case j_int: + buf.read_be(int_data); // same as float data really + break; + case j_double: + case j_long: + buf.read_be(long_data); // same as double + break; + case j_class: + buf.read_be(ref_type.class_idx); + break; + case j_fieldref: + case j_methodref: + case j_interface_methodref: + buf.read_be(ref_type.class_idx); + buf.read_be(ref_type.name_and_type_idx); + break; + case j_string: + buf.read_be(index); + break; + case j_string_data: + // HACK HACK: for now, we call these UTF-8 and do no further processing. + // Later, we should do some decoding. It's really modified UTF-8 + // * U+0000 is represented as 0xC0,0x80 invalid character + // * any single zero byte ends the string + // * characters above U+10000 are encoded like in CESU-8 + buf.read_jstr(str_data); + break; + case j_nameandtype: + buf.read_be(name_and_type.name_index); + buf.read_be(name_and_type.descriptor_index); + break; + } + } + + constant(int fake) + { + type = j_hole; + } + + std::string toString() + { + std::ostringstream ss; + switch (type) + { + case j_hole: + ss << "Fake legacy entry"; + break; + case j_float: + ss << "Float: " << float_data; + break; + case j_double: + ss << "Double: " << double_data; + break; + case j_int: + ss << "Int: " << int_data; + break; + case j_long: + ss << "Long: " << long_data; + break; + case j_string_data: + ss << "StrData: " << str_data; + break; + case j_string: + ss << "Str: " << index; + break; + case j_fieldref: + ss << "FieldRef: " << ref_type.class_idx << " " << ref_type.name_and_type_idx; + break; + case j_methodref: + ss << "MethodRef: " << ref_type.class_idx << " " << ref_type.name_and_type_idx; + break; + case j_interface_methodref: + ss << "IfMethodRef: " << ref_type.class_idx << " " << ref_type.name_and_type_idx; + break; + case j_class: + ss << "Class: " << ref_type.class_idx; + break; + case j_nameandtype: + ss << "NameAndType: " << name_and_type.name_index << " " + << name_and_type.descriptor_index; + break; + } + return ss.str(); + } + + std::string str_data; /** String data in 'modified utf-8'.*/ + // store everything here. + union + { + int32_t int_data; + int64_t long_data; + float float_data; + double double_data; + uint16_t index; + struct + { + /** + * Class reference: + * an index within the constant pool to a UTF-8 string containing + * the fully qualified class name (in internal format) + * Used for j_class, j_fieldref, j_methodref and j_interface_methodref + */ + uint16_t class_idx; + // used for j_fieldref, j_methodref and j_interface_methodref + uint16_t name_and_type_idx; + } ref_type; + struct + { + uint16_t name_index; + uint16_t descriptor_index; + } name_and_type; + }; +}; + +/** + * A helper class that represents the custom container used in Java class file for storage of + * constants + */ +class constant_pool +{ +public: + /** + * Create a pool of constants + */ + constant_pool() + { + } + /** + * Load a java constant pool + */ + void load(util::membuffer &buf) + { + uint16_t length = 0; + buf.read_be(length); + length--; + uint16_t index = 1; + const constant *last_constant = nullptr; + while (length) + { + const constant &cnst = constant(buf); + constants.push_back(cnst); + last_constant = &constants[constants.size() - 1]; + if (last_constant->type == constant::j_double || + last_constant->type == constant::j_long) + { + // push in a fake constant to preserve indexing + constants.push_back(constant(0)); + length -= 2; + index += 2; + } + else + { + length--; + index++; + } + } + } + typedef std::vector<java::constant> container_type; + /** + * Access constants based on jar file index numbers (index of the first element is 1) + */ + java::constant &operator[](std::size_t constant_index) + { + if (constant_index == 0 || constant_index > constants.size()) + { + throw new classfile_exception(); + } + return constants[constant_index - 1]; + } + ; + container_type::const_iterator begin() const + { + return constants.begin(); + } + ; + container_type::const_iterator end() const + { + return constants.end(); + } + +private: + container_type constants; +}; +} |