JDK14/Java14源码在线阅读
/*
* Copyright (c) 1994, 2019, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*-
* Verify that the code within a method block doesn't exploit any
* security holes.
*/
/*
Exported function:
jboolean
VerifyClassForMajorVersion(JNIEnv *env, jclass cb, char *message_buffer,
jint buffer_length, jint major_version)
This file now only uses the standard JNI and the following VM functions
exported in jvm.h:
JVM_FindClassFromClass
JVM_IsInterface
JVM_GetClassNameUTF
JVM_GetClassCPEntriesCount
JVM_GetClassCPTypes
JVM_GetClassFieldsCount
JVM_GetClassMethodsCount
JVM_GetFieldIxModifiers
JVM_GetMethodIxModifiers
JVM_GetMethodIxExceptionTableLength
JVM_GetMethodIxLocalsCount
JVM_GetMethodIxArgsSize
JVM_GetMethodIxMaxStack
JVM_GetMethodIxNameUTF
JVM_GetMethodIxSignatureUTF
JVM_GetMethodIxExceptionsCount
JVM_GetMethodIxExceptionIndexes
JVM_GetMethodIxByteCodeLength
JVM_GetMethodIxByteCode
JVM_GetMethodIxExceptionTableEntry
JVM_IsConstructorIx
JVM_GetCPClassNameUTF
JVM_GetCPFieldNameUTF
JVM_GetCPMethodNameUTF
JVM_GetCPFieldSignatureUTF
JVM_GetCPMethodSignatureUTF
JVM_GetCPFieldClassNameUTF
JVM_GetCPMethodClassNameUTF
JVM_GetCPFieldModifiers
JVM_GetCPMethodModifiers
JVM_ReleaseUTF
JVM_IsSameClassPackage
*/
#include <string.h>
#include <setjmp.h>
#include <assert.h>
#include <limits.h>
#include <stdlib.h>
#include "jni.h"
#include "jni_util.h"
#include "jvm.h"
#include "classfile_constants.h"
#include "opcodes.in_out"
/* On AIX malloc(0) and calloc(0, ...) return a NULL pointer, which is legal,
* but the code here does not handles it. So we wrap the methods and return non-NULL
* pointers even if we allocate 0 bytes.
*/
#ifdef _AIX
static int aix_dummy;
static void* aix_malloc(size_t len) {
if (len == 0) {
return &aix_dummy;
}
return malloc(len);
}
static void* aix_calloc(size_t n, size_t size) {
if (n == 0) {
return &aix_dummy;
}
return calloc(n, size);
}
static void aix_free(void* p) {
if (p == &aix_dummy) {
return;
}
free(p);
}
#undef malloc
#undef calloc
#undef free
#define malloc aix_malloc
#define calloc aix_calloc
#define free aix_free
#endif
#ifdef __APPLE__
/* use setjmp/longjmp versions that do not save/restore the signal mask */
#define setjmp _setjmp
#define longjmp _longjmp
#endif
#define MAX_ARRAY_DIMENSIONS 255
/* align byte code */
#ifndef ALIGN_UP
#define ALIGN_UP(n,align_grain) (((n) + ((align_grain) - 1)) & ~((align_grain)-1))
#endif /* ALIGN_UP */
#define UCALIGN(n) ((unsigned char *)ALIGN_UP((uintptr_t)(n),sizeof(int)))
#ifdef DEBUG
int verify_verbose = 0;
static struct context_type *GlobalContext;
#endif
enum {
ITEM_Bogus,
ITEM_Void, /* only as a function return value */
ITEM_Integer,
ITEM_Float,
ITEM_Double,
ITEM_Double_2, /* 2nd word of double in register */
ITEM_Long,
ITEM_Long_2, /* 2nd word of long in register */
ITEM_Array,
ITEM_Object, /* Extra info field gives name. */
ITEM_NewObject, /* Like object, but uninitialized. */
ITEM_InitObject, /* "this" is init method, before call
to super() */
ITEM_ReturnAddress, /* Extra info gives instr # of start pc */
/* The following four are only used within array types.
* Normally, we use ITEM_Integer, instead. */
ITEM_Byte,
ITEM_Short,
ITEM_Char,
ITEM_Boolean
};
#define UNKNOWN_STACK_SIZE -1
#define UNKNOWN_REGISTER_COUNT -1
#define UNKNOWN_RET_INSTRUCTION -1
#undef MAX
#undef MIN
#define MAX(a, b) ((a) > (b) ? (a) : (b))
#define MIN(a, b) ((a) < (b) ? (a) : (b))
#define BITS_PER_INT (CHAR_BIT * sizeof(int)/sizeof(char))
#define SET_BIT(flags, i) (flags[(i)/BITS_PER_INT] |= \
((unsigned)1 << ((i) % BITS_PER_INT)))
#define IS_BIT_SET(flags, i) (flags[(i)/BITS_PER_INT] & \
((unsigned)1 << ((i) % BITS_PER_INT)))
typedef unsigned int fullinfo_type;
typedef unsigned int *bitvector;
#define GET_ITEM_TYPE(thing) ((thing) & 0x1F)
#define GET_INDIRECTION(thing) (((thing) & 0xFFFF) >> 5)
#define GET_EXTRA_INFO(thing) ((thing) >> 16)
#define WITH_ZERO_INDIRECTION(thing) ((thing) & ~(0xFFE0))
#define WITH_ZERO_EXTRA_INFO(thing) ((thing) & 0xFFFF)
#define MAKE_FULLINFO(type, indirect, extra) \
((type) + ((indirect) << 5) + ((extra) << 16))
#define MAKE_Object_ARRAY(indirect) \
(context->object_info + ((indirect) << 5))
#define NULL_FULLINFO MAKE_FULLINFO(ITEM_Object, 0, 0)
/* JVM_OPC_invokespecial calls to <init> need to be treated special */
#define JVM_OPC_invokeinit 0x100
/* A hash mechanism used by the verifier.
* Maps class names to unique 16 bit integers.
*/
#define HASH_TABLE_SIZE 503
/* The buckets are managed as a 256 by 256 matrix. We allocate an entire
* row (256 buckets) at a time to minimize fragmentation. Rows are
* allocated on demand so that we don't waste too much space.
*/
#define MAX_HASH_ENTRIES 65536
#define HASH_ROW_SIZE 256
typedef struct hash_bucket_type {
char *name;
unsigned int hash;
jclass class;
unsigned short ID;
unsigned short next;
unsigned loadable:1; /* from context->class loader */
} hash_bucket_type;
typedef struct {
hash_bucket_type **buckets;
unsigned short *table;
int entries_used;
} hash_table_type;
#define GET_BUCKET(class_hash, ID)\
(class_hash->buckets[ID / HASH_ROW_SIZE] + ID % HASH_ROW_SIZE)
/*
* There are currently two types of resources that we need to keep
* track of (in addition to the CCalloc pool).
*/
enum {
VM_STRING_UTF, /* VM-allocated UTF strings */
VM_MALLOC_BLK /* malloc'ed blocks */
};
#define LDC_CLASS_MAJOR_VERSION 49
#define LDC_METHOD_HANDLE_MAJOR_VERSION 51
#define NONZERO_PADDING_BYTES_IN_SWITCH_MAJOR_VERSION 51
#define STATIC_METHOD_IN_INTERFACE_MAJOR_VERSION 52
#define ALLOC_STACK_SIZE 16 /* big enough */
typedef struct alloc_stack_type {
void *ptr;
int kind;
struct alloc_stack_type *next;
} alloc_stack_type;
/* The context type encapsulates the current invocation of the byte
* code verifier.
*/
struct context_type {
JNIEnv *env; /* current JNIEnv */
/* buffers etc. */
char *message;
jint message_buf_len;
jboolean err_code;
alloc_stack_type *allocated_memory; /* all memory blocks that we have not
had a chance to free */
/* Store up to ALLOC_STACK_SIZE number of handles to allocated memory
blocks here, to save mallocs. */
alloc_stack_type alloc_stack[ALLOC_STACK_SIZE];
int alloc_stack_top;
/* these fields are per class */
jclass class; /* current class */
jint major_version;
jint nconstants;
unsigned char *constant_types;
hash_table_type class_hash;
fullinfo_type object_info; /* fullinfo for java/lang/Object */
fullinfo_type string_info; /* fullinfo for java/lang/String */
fullinfo_type throwable_info; /* fullinfo for java/lang/Throwable */
fullinfo_type cloneable_info; /* fullinfo for java/lang/Cloneable */
fullinfo_type serializable_info; /* fullinfo for java/io/Serializable */
fullinfo_type currentclass_info; /* fullinfo for context->class */
fullinfo_type superclass_info; /* fullinfo for superclass */
/* these fields are per method */
int method_index; /* current method */
unsigned short *exceptions; /* exceptions */
unsigned char *code; /* current code object */
jint code_length;
int *code_data; /* offset to instruction number */
struct instruction_data_type *instruction_data; /* info about each */
struct handler_info_type *handler_info;
fullinfo_type *superclasses; /* null terminated superclasses */
int instruction_count; /* number of instructions */
fullinfo_type return_type; /* function return type */
fullinfo_type swap_table[4]; /* used for passing information */
int bitmask_size; /* words needed to hold bitmap of arguments */
/* these fields are per field */
int field_index;
/* Used by the space allocator */
struct CCpool *CCroot, *CCcurrent;
char *CCfree_ptr;
int CCfree_size;
/* Jump here on any error. */
jmp_buf jump_buffer;
#ifdef DEBUG
/* keep track of how many global refs are allocated. */
int n_globalrefs;
#endif
};
struct stack_info_type {
struct stack_item_type *stack;
int stack_size;
};
struct register_info_type {
int register_count; /* number of registers used */
fullinfo_type *registers;
int mask_count; /* number of masks in the following */
struct mask_type *masks;
};
struct mask_type {
int entry;
int *modifies;
};
typedef unsigned short flag_type;
struct instruction_data_type {
int opcode; /* may turn into "canonical" opcode */
unsigned changed:1; /* has it changed */
unsigned protected:1; /* must accessor be a subclass of "this" */
union {
int i; /* operand to the opcode */
int *ip;
fullinfo_type fi;
} operand, operand2;
fullinfo_type p;
struct stack_info_type stack_info;
struct register_info_type register_info;
#define FLAG_REACHED 0x01 /* instruction reached */
#define FLAG_NEED_CONSTRUCTOR 0x02 /* must call this.<init> or super.<init> */
#define FLAG_NO_RETURN 0x04 /* must throw out of method */
flag_type or_flags; /* true for at least one path to this inst */
#define FLAG_CONSTRUCTED 0x01 /* this.<init> or super.<init> called */
flag_type and_flags; /* true for all paths to this instruction */
};
struct handler_info_type {
int start, end, handler;
struct stack_info_type stack_info;
};
struct stack_item_type {
fullinfo_type item;
struct stack_item_type *next;
};
typedef struct context_type context_type;
typedef struct instruction_data_type instruction_data_type;
typedef struct stack_item_type stack_item_type;
typedef struct register_info_type register_info_type;
typedef struct stack_info_type stack_info_type;
typedef struct mask_type mask_type;
static void read_all_code(context_type *context, jclass cb, int num_methods,
int** code_lengths, unsigned char*** code);
static void verify_method(context_type *context, jclass cb, int index,
int code_length, unsigned char* code);
static void free_all_code(context_type* context, int num_methods,
unsigned char** code);
static void verify_field(context_type *context, jclass cb, int index);
static void verify_opcode_operands (context_type *, unsigned int inumber, int offset);
static void set_protected(context_type *, unsigned int inumber, int key, int);
static jboolean is_superclass(context_type *, fullinfo_type);
static void initialize_exception_table(context_type *);
static int instruction_length(unsigned char *iptr, unsigned char *end);
static jboolean isLegalTarget(context_type *, int offset);
static void verify_constant_pool_type(context_type *, int, unsigned);
static void initialize_dataflow(context_type *);
static void run_dataflow(context_type *context);
static void check_register_values(context_type *context, unsigned int inumber);
static void check_flags(context_type *context, unsigned int inumber);
static void pop_stack(context_type *, unsigned int inumber, stack_info_type *);
static void update_registers(context_type *, unsigned int inumber, register_info_type *);
static void update_flags(context_type *, unsigned int inumber,
flag_type *new_and_flags, flag_type *new_or_flags);
static void push_stack(context_type *, unsigned int inumber, stack_info_type *stack);
static void merge_into_successors(context_type *, unsigned int inumber,
register_info_type *register_info,
stack_info_type *stack_info,
flag_type and_flags, flag_type or_flags);
static void merge_into_one_successor(context_type *context,
unsigned int from_inumber,
unsigned int inumber,
register_info_type *register_info,
stack_info_type *stack_info,
flag_type and_flags, flag_type or_flags,
jboolean isException);
static void merge_stack(context_type *, unsigned int inumber,
unsigned int to_inumber, stack_info_type *);
static void merge_registers(context_type *, unsigned int inumber,
unsigned int to_inumber,
register_info_type *);
static void merge_flags(context_type *context, unsigned int from_inumber,
unsigned int to_inumber,
flag_type new_and_flags, flag_type new_or_flags);
static stack_item_type *copy_stack(context_type *, stack_item_type *);
static mask_type *copy_masks(context_type *, mask_type *masks, int mask_count);
static mask_type *add_to_masks(context_type *, mask_type *, int , int);
static fullinfo_type decrement_indirection(fullinfo_type);
static fullinfo_type merge_fullinfo_types(context_type *context,
fullinfo_type a,
fullinfo_type b,
jboolean assignment);
static jboolean isAssignableTo(context_type *,
fullinfo_type a,
fullinfo_type b);
static jclass object_fullinfo_to_classclass(context_type *, fullinfo_type);
#define NEW(type, count) \
((type *)CCalloc(context, (count)*(sizeof(type)), JNI_FALSE))
#define ZNEW(type, count) \
((type *)CCalloc(context, (count)*(sizeof(type)), JNI_TRUE))
static void CCinit(context_type *context);
static void CCreinit(context_type *context);
static void CCdestroy(context_type *context);
static void *CCalloc(context_type *context, int size, jboolean zero);
static fullinfo_type cp_index_to_class_fullinfo(context_type *, int, int);
static const char* get_result_signature(const char* signature);
static char signature_to_fieldtype(context_type *context,
const char **signature_p, fullinfo_type *info);
static void CCerror (context_type *, char *format, ...);
static void CFerror (context_type *, char *format, ...);
static void CCout_of_memory (context_type *);
/* Because we can longjmp any time, we need to be very careful about
* remembering what needs to be freed. */
static void check_and_push(context_type *context, const void *ptr, int kind);
static void pop_and_free(context_type *context);
static int signature_to_args_size(const char *method_signature);
#ifdef DEBUG
static void print_stack (context_type *, stack_info_type *stack_info);
static void print_registers(context_type *, register_info_type *register_info);
static void print_flags(context_type *, flag_type, flag_type);
static void print_formatted_fieldname(context_type *context, int index);
static void print_formatted_methodname(context_type *context, int index);
#endif
/*
* Declare library specific JNI_Onload entry if static build
*/
DEF_STATIC_JNI_OnLoad
void initialize_class_hash(context_type *context)
{
hash_table_type *class_hash = &(context->class_hash);
class_hash->buckets = (hash_bucket_type **)
calloc(MAX_HASH_ENTRIES / HASH_ROW_SIZE, sizeof(hash_bucket_type *));
class_hash->table = (unsigned short *)
calloc(HASH_TABLE_SIZE, sizeof(unsigned short));
if (class_hash->buckets == 0 ||
class_hash->table == 0)
CCout_of_memory(context);
class_hash->entries_used = 0;
}
static void finalize_class_hash(context_type *context)
{
hash_table_type *class_hash = &(context->class_hash);
JNIEnv *env = context->env;
int i;
/* 4296677: bucket index starts from 1. */
for (i=1;i<=class_hash->entries_used;i++) {
hash_bucket_type *bucket = GET_BUCKET(class_hash, i);
assert(bucket != NULL);
free(bucket->name);
if (bucket->class) {
(*env)->DeleteGlobalRef(env, bucket->class);
#ifdef DEBUG
context->n_globalrefs--;
#endif
}
}
if (class_hash->buckets) {
for (i=0;i<MAX_HASH_ENTRIES / HASH_ROW_SIZE; i++) {
if (class_hash->buckets[i] == 0)
break;
free(class_hash->buckets[i]);
}
}
free(class_hash->buckets);
free(class_hash->table);
}
static hash_bucket_type *
new_bucket(context_type *context, unsigned short *pID)
{
hash_table_type *class_hash = &(context->class_hash);
int i = *pID = class_hash->entries_used + 1;
int row = i / HASH_ROW_SIZE;
if (i >= MAX_HASH_ENTRIES)
CCerror(context, "Exceeded verifier's limit of 65535 referred classes");
if (class_hash->buckets[row] == 0) {
class_hash->buckets[row] = (hash_bucket_type*)
calloc(HASH_ROW_SIZE, sizeof(hash_bucket_type));
if (class_hash->buckets[row] == 0)
CCout_of_memory(context);
}
class_hash->entries_used++; /* only increment when we are sure there
is no overflow. */
return GET_BUCKET(class_hash, i);
}
static unsigned int
class_hash_fun(const char *s)
{
int i;
unsigned raw_hash;
for (raw_hash = 0; (i = *s) != '\0'; ++s)
raw_hash = raw_hash * 37 + i;
return raw_hash;
}
/*
* Find a class using the defining loader of the current class
* and return a local reference to it.
*/
static jclass load_class_local(context_type *context,const char *classname)
{
jclass cb = JVM_FindClassFromClass(context->env, classname,
JNI_FALSE, context->class);
if (cb == 0)
CCerror(context, "Cannot find class %s", classname);
return cb;
}
/*
* Find a class using the defining loader of the current class
* and return a global reference to it.
*/
static jclass load_class_global(context_type *context, const char *classname)
{
JNIEnv *env = context->env;
jclass local, global;
local = load_class_local(context, classname);
global = (*env)->NewGlobalRef(env, local);
if (global == 0)
CCout_of_memory(context);
#ifdef DEBUG
context->n_globalrefs++;
#endif
(*env)->DeleteLocalRef(env, local);
return global;
}
/*
* Return a unique ID given a local class reference. The loadable
* flag is true if the defining class loader of context->class
* is known to be capable of loading the class.
*/
static unsigned short
class_to_ID(context_type *context, jclass cb, jboolean loadable)
{
JNIEnv *env = context->env;
hash_table_type *class_hash = &(context->class_hash);
unsigned int hash;
hash_bucket_type *bucket;
unsigned short *pID;
const char *name = JVM_GetClassNameUTF(env, cb);
check_and_push(context, name, VM_STRING_UTF);
hash = class_hash_fun(name);
pID = &(class_hash->table[hash % HASH_TABLE_SIZE]);
while (*pID) {
bucket = GET_BUCKET(class_hash, *pID);
if (bucket->hash == hash && strcmp(name, bucket->name) == 0) {
/*
* There is an unresolved entry with our name
* so we're forced to load it in case it matches us.
*/
if (bucket->class == 0) {
assert(bucket->loadable == JNI_TRUE);
bucket->class = load_class_global(context, name);
}
/*
* It's already in the table. Update the loadable
* state if it's known and then we're done.
*/
if ((*env)->IsSameObject(env, cb, bucket->class)) {
if (loadable && !bucket->loadable)
bucket->loadable = JNI_TRUE;
goto done;
}
}
pID = &bucket->next;
}
bucket = new_bucket(context, pID);
bucket->next = 0;
bucket->hash = hash;
bucket->name = malloc(strlen(name) + 1);
if (bucket->name == 0)
CCout_of_memory(context);
strcpy(bucket->name, name);
bucket->loadable = loadable;
bucket->class = (*env)->NewGlobalRef(env, cb);
if (bucket->class == 0)
CCout_of_memory(context);
#ifdef DEBUG
context->n_globalrefs++;
#endif
done:
pop_and_free(context);
return *pID;
}
/*
* Return a unique ID given a class name from the constant pool.
* All classes are lazily loaded from the defining loader of
* context->class.
*/
static unsigned short
class_name_to_ID(context_type *context, const char *name)
{
hash_table_type *class_hash = &(context->class_hash);
unsigned int hash = class_hash_fun(name);
hash_bucket_type *bucket;
unsigned short *pID;
jboolean force_load = JNI_FALSE;
pID = &(class_hash->table[hash % HASH_TABLE_SIZE]);
while (*pID) {
bucket = GET_BUCKET(class_hash, *pID);
if (bucket->hash == hash && strcmp(name, bucket->name) == 0) {
if (bucket->loadable)
goto done;
force_load = JNI_TRUE;
}
pID = &bucket->next;
}
if (force_load) {
/*
* We found at least one matching named entry for a class that
* was not known to be loadable through the defining class loader
* of context->class. We must load our named class and update
* the hash table in case one these entries matches our class.
*/
JNIEnv *env = context->env;
jclass cb = load_class_local(context, name);
unsigned short id = class_to_ID(context, cb, JNI_TRUE);
(*env)->DeleteLocalRef(env, cb);
return id;
}
bucket = new_bucket(context, pID);
bucket->next = 0;
bucket->class = 0;
bucket->loadable = JNI_TRUE; /* name-only IDs are implicitly loadable */
bucket->hash = hash;
bucket->name = malloc(strlen(name) + 1);
if (bucket->name == 0)
CCout_of_memory(context);
strcpy(bucket->name, name);
done:
return *pID;
}
#ifdef DEBUG
static const char *
ID_to_class_name(context_type *context, unsigned short ID)
{
hash_table_type *class_hash = &(context->class_hash);
hash_bucket_type *bucket = GET_BUCKET(class_hash, ID);
return bucket->name;
}
#endif
static jclass
ID_to_class(context_type *context, unsigned short ID)
{
hash_table_type *class_hash = &(context->class_hash);
hash_bucket_type *bucket = GET_BUCKET(class_hash, ID);
if (bucket->class == 0) {
assert(bucket->loadable == JNI_TRUE);
bucket->class = load_class_global(context, bucket->name);
}
return bucket->class;
}
static fullinfo_type
make_loadable_class_info(context_type *context, jclass cb)
{
return MAKE_FULLINFO(ITEM_Object, 0,
class_to_ID(context, cb, JNI_TRUE));
}
static fullinfo_type
make_class_info(context_type *context, jclass cb)
{
return MAKE_FULLINFO(ITEM_Object, 0,
class_to_ID(context, cb, JNI_FALSE));
}
static fullinfo_type
make_class_info_from_name(context_type *context, const char *name)
{
return MAKE_FULLINFO(ITEM_Object, 0,
class_name_to_ID(context, name));
}
/* RETURNS
* 1: on success chosen to be consistent with previous VerifyClass
* 0: verify error
* 2: out of memory
* 3: class format error
*
* Called by verify_class. Verify the code of each of the methods
* in a class. Note that this function apparently can't be JNICALL,
* because if it is the dynamic linker doesn't appear to be able to
* find it on Win32.
*/
#define CC_OK 1
#define CC_VerifyError 0
#define CC_OutOfMemory 2
#define CC_ClassFormatError 3
JNIEXPORT jboolean
VerifyClassForMajorVersion(JNIEnv *env, jclass cb, char *buffer, jint len,
jint major_version)
{
context_type context_structure;
context_type *context = &context_structure;
jboolean result = CC_OK;
int i;
int num_methods;
int* code_lengths;
unsigned char** code;
#ifdef DEBUG
GlobalContext = context;
#endif
memset(context, 0, sizeof(context_type));
context->message = buffer;
context->message_buf_len = len;
context->env = env;
context->class = cb;
/* Set invalid method/field index of the context, in case anyone
calls CCerror */
context->method_index = -1;
context->field_index = -1;
/* Don't call CCerror or anything that can call it above the setjmp! */
if (!setjmp(context->jump_buffer)) {
jclass super;
CCinit(context); /* initialize heap; may throw */
initialize_class_hash(context);
context->major_version = major_version;
context->nconstants = JVM_GetClassCPEntriesCount(env, cb);
context->constant_types = (unsigned char *)
malloc(sizeof(unsigned char) * context->nconstants + 1);
if (context->constant_types == 0)
CCout_of_memory(context);
JVM_GetClassCPTypes(env, cb, context->constant_types);
if (context->constant_types == 0)
CCout_of_memory(context);
context->object_info =
make_class_info_from_name(context, "java/lang/Object");
context->string_info =
make_class_info_from_name(context, "java/lang/String");
context->throwable_info =
make_class_info_from_name(context, "java/lang/Throwable");
context->cloneable_info =
make_class_info_from_name(context, "java/lang/Cloneable");
context->serializable_info =
make_class_info_from_name(context, "java/io/Serializable");
context->currentclass_info = make_loadable_class_info(context, cb);
super = (*env)->GetSuperclass(env, cb);
if (super != 0) {
fullinfo_type *gptr;
int i = 0;
context->superclass_info = make_loadable_class_info(context, super);
while(super != 0) {
jclass tmp_cb = (*env)->GetSuperclass(env, super);
(*env)->DeleteLocalRef(env, super);
super = tmp_cb;
i++;
}
(*env)->DeleteLocalRef(env, super);
super = 0;
/* Can't go on context heap since it survives more than
one method */
context->superclasses = gptr =
malloc(sizeof(fullinfo_type)*(i + 1));
if (gptr == 0) {
CCout_of_memory(context);
}
super = (*env)->GetSuperclass(env, context->class);
while(super != 0) {
jclass tmp_cb;
*gptr++ = make_class_info(context, super);
tmp_cb = (*env)->GetSuperclass(env, super);
(*env)->DeleteLocalRef(env, super);
super = tmp_cb;
}
*gptr = 0;
} else {
context->superclass_info = 0;
}
(*env)->DeleteLocalRef(env, super);
/* Look at each method */
for (i = JVM_GetClassFieldsCount(env, cb); --i >= 0;)
verify_field(context, cb, i);
num_methods = JVM_GetClassMethodsCount(env, cb);
read_all_code(context, cb, num_methods, &code_lengths, &code);
for (i = num_methods - 1; i >= 0; --i)
verify_method(context, cb, i, code_lengths[i], code[i]);
free_all_code(context, num_methods, code);
result = CC_OK;
} else {
result = context->err_code;
}
/* Cleanup */
finalize_class_hash(context);
while(context->allocated_memory)
pop_and_free(context);
#ifdef DEBUG
GlobalContext = 0;
#endif
if (context->exceptions)
free(context->exceptions);
if (context->constant_types)
free(context->constant_types);
if (context->superclasses)
free(context->superclasses);
#ifdef DEBUG
/* Make sure all global refs created in the verifier are freed */
assert(context->n_globalrefs == 0);
#endif
CCdestroy(context); /* destroy heap */
return result;
}
static void
verify_field(context_type *context, jclass cb, int field_index)
{
JNIEnv *env = context->env;
int access_bits = JVM_GetFieldIxModifiers(env, cb, field_index);
context->field_index = field_index;
if ( ((access_bits & JVM_ACC_PUBLIC) != 0) &&
((access_bits & (JVM_ACC_PRIVATE | JVM_ACC_PROTECTED)) != 0)) {
CCerror(context, "Inconsistent access bits.");
}
context->field_index = -1;
}
/**
* We read all of the class's methods' code because it is possible that
* the verification of one method could resulting in linking further
* down the stack (due to class loading), which could end up rewriting
* some of the bytecode of methods we haven't verified yet. Since we
* don't want to see the rewritten bytecode, cache all the code and
* operate only on that.
*/
static void
read_all_code(context_type* context, jclass cb, int num_methods,
int** lengths_addr, unsigned char*** code_addr)
{
int* lengths;
unsigned char** code;
int i;
lengths = malloc(sizeof(int) * num_methods);
check_and_push(context, lengths, VM_MALLOC_BLK);
code = malloc(sizeof(unsigned char*) * num_methods);
check_and_push(context, code, VM_MALLOC_BLK);
*(lengths_addr) = lengths;
*(code_addr) = code;
for (i = 0; i < num_methods; ++i) {
lengths[i] = JVM_GetMethodIxByteCodeLength(context->env, cb, i);
if (lengths[i] > 0) {
code[i] = malloc(sizeof(unsigned char) * (lengths[i] + 1));
check_and_push(context, code[i], VM_MALLOC_BLK);
JVM_GetMethodIxByteCode(context->env, cb, i, code[i]);
} else {
code[i] = NULL;
}
}
}
static void
free_all_code(context_type* context, int num_methods, unsigned char** code)
{
int i;
for (i = 0; i < num_methods; ++i) {
if (code[i] != NULL) {
pop_and_free(context);
}
}
pop_and_free(context); /* code */
pop_and_free(context); /* lengths */
}
/* Verify the code of one method */
static void
verify_method(context_type *context, jclass cb, int method_index,
int code_length, unsigned char* code)
{
JNIEnv *env = context->env;
int access_bits = JVM_GetMethodIxModifiers(env, cb, method_index);
int *code_data;
instruction_data_type *idata = 0;
int instruction_count;
int i, offset;
unsigned int inumber;
jint nexceptions;
if ((access_bits & (JVM_ACC_NATIVE | JVM_ACC_ABSTRACT)) != 0) {
/* not much to do for abstract and native methods */
return;
}
context->code_length = code_length;
context->code = code;
/* CCerror can give method-specific info once this is set */
context->method_index = method_index;
CCreinit(context); /* initial heap */
code_data = NEW(int, code_length);
#ifdef DEBUG
if (verify_verbose) {
const char *classname = JVM_GetClassNameUTF(env, cb);
const char *methodname =
JVM_GetMethodIxNameUTF(env, cb, method_index);
const char *signature =
JVM_GetMethodIxSignatureUTF(env, cb, method_index);
jio_fprintf(stdout, "Looking at %s.%s%s\n",
(classname ? classname : ""),
(methodname ? methodname : ""),
(signature ? signature : ""));
JVM_ReleaseUTF(classname);
JVM_ReleaseUTF(methodname);
JVM_ReleaseUTF(signature);
}
#endif
if (((access_bits & JVM_ACC_PUBLIC) != 0) &&
((access_bits & (JVM_ACC_PRIVATE | JVM_ACC_PROTECTED)) != 0)) {
CCerror(context, "Inconsistent access bits.");
}
// If this method is an overpass method, which is generated by the VM,
// we trust the code and no check needs to be done.
if (JVM_IsVMGeneratedMethodIx(env, cb, method_index)) {
return;
}
/* Run through the code. Mark the start of each instruction, and give
* the instruction a number */
for (i = 0, offset = 0; offset < code_length; i++) {
int length = instruction_length(&code[offset], code + code_length);
int next_offset = offset + length;
if (length <= 0)
CCerror(context, "Illegal instruction found at offset %d", offset);
if (next_offset > code_length)
CCerror(context, "Code stops in the middle of instruction "
" starting at offset %d", offset);
code_data[offset] = i;
while (++offset < next_offset)
code_data[offset] = -1; /* illegal location */
}
instruction_count = i; /* number of instructions in code */
/* Allocate a structure to hold info about each instruction. */
idata = NEW(instruction_data_type, instruction_count);
/* Initialize the heap, and other info in the context structure. */
context->code = code;
context->instruction_data = idata;
context->code_data = code_data;
context->instruction_count = instruction_count;
context->handler_info =
NEW(struct handler_info_type,
JVM_GetMethodIxExceptionTableLength(env, cb, method_index));
context->bitmask_size =
(JVM_GetMethodIxLocalsCount(env, cb, method_index)
+ (BITS_PER_INT - 1))/BITS_PER_INT;
if (instruction_count == 0)
CCerror(context, "Empty code");
for (inumber = 0, offset = 0; offset < code_length; inumber++) {
int length = instruction_length(&code[offset], code + code_length);
instruction_data_type *this_idata = &idata[inumber];
this_idata->opcode = code[offset];
this_idata->stack_info.stack = NULL;
this_idata->stack_info.stack_size = UNKNOWN_STACK_SIZE;
this_idata->register_info.register_count = UNKNOWN_REGISTER_COUNT;
this_idata->changed = JNI_FALSE; /* no need to look at it yet. */
this_idata->protected = JNI_FALSE; /* no need to look at it yet. */
this_idata->and_flags = (flag_type) -1; /* "bottom" and value */
this_idata->or_flags = 0; /* "bottom" or value*/
/* This also sets up this_data->operand. It also makes the
* xload_x and xstore_x instructions look like the generic form. */
verify_opcode_operands(context, inumber, offset);
offset += length;
}
/* make sure exception table is reasonable. */
initialize_exception_table(context);
/* Set up first instruction, and start of exception handlers. */
initialize_dataflow(context);
/* Run data flow analysis on the instructions. */
run_dataflow(context);
/* verify checked exceptions, if any */
nexceptions = JVM_GetMethodIxExceptionsCount(env, cb, method_index);
context->exceptions = (unsigned short *)
malloc(sizeof(unsigned short) * nexceptions + 1);
if (context->exceptions == 0)
CCout_of_memory(context);
JVM_GetMethodIxExceptionIndexes(env, cb, method_index,
context->exceptions);
for (i = 0; i < nexceptions; i++) {
/* Make sure the constant pool item is JVM_CONSTANT_Class */
verify_constant_pool_type(context, (int)context->exceptions[i],
1 << JVM_CONSTANT_Class);
}
free(context->exceptions);
context->exceptions = 0;
context->code = 0;
context->method_index = -1;
}
/* Look at a single instruction, and verify its operands. Also, for
* simplicity, move the operand into the ->operand field.
* Make sure that branches don't go into the middle of nowhere.
*/
static jint _ck_ntohl(jint n)
{
unsigned char *p = (unsigned char *)&n;
return (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3];
}
static void
verify_opcode_operands(context_type *context, unsigned int inumber, int offset)
{
JNIEnv *env = context->env;
instruction_data_type *idata = context->instruction_data;
instruction_data_type *this_idata = &idata[inumber];
int *code_data = context->code_data;
int mi = context->method_index;
unsigned char *code = context->code;
int opcode = this_idata->opcode;
int var;
/*
* Set the ip fields to 0 not the i fields because the ip fields
* are 64 bits on 64 bit architectures, the i field is only 32
*/
this_idata->operand.ip = 0;
this_idata->operand2.ip = 0;
switch (opcode) {
case JVM_OPC_jsr:
/* instruction of ret statement */
this_idata->operand2.i = UNKNOWN_RET_INSTRUCTION;
/* FALLTHROUGH */
case JVM_OPC_ifeq: case JVM_OPC_ifne: case JVM_OPC_iflt:
case JVM_OPC_ifge: case JVM_OPC_ifgt: case JVM_OPC_ifle:
case JVM_OPC_ifnull: case JVM_OPC_ifnonnull:
case JVM_OPC_if_icmpeq: case JVM_OPC_if_icmpne: case JVM_OPC_if_icmplt:
case JVM_OPC_if_icmpge: case JVM_OPC_if_icmpgt: case JVM_OPC_if_icmple:
case JVM_OPC_if_acmpeq: case JVM_OPC_if_acmpne:
case JVM_OPC_goto: {
/* Set the ->operand to be the instruction number of the target. */
int jump = (((signed char)(code[offset+1])) << 8) + code[offset+2];
int target = offset + jump;
if (!isLegalTarget(context, target))
CCerror(context, "Illegal target of jump or branch");
this_idata->operand.i = code_data[target];
break;
}
case JVM_OPC_jsr_w:
/* instruction of ret statement */
this_idata->operand2.i = UNKNOWN_RET_INSTRUCTION;
/* FALLTHROUGH */
case JVM_OPC_goto_w: {
/* Set the ->operand to be the instruction number of the target. */
int jump = (((signed char)(code[offset+1])) << 24) +
(code[offset+2] << 16) + (code[offset+3] << 8) +
(code[offset + 4]);
int target = offset + jump;
if (!isLegalTarget(context, target))
CCerror(context, "Illegal target of jump or branch");
this_idata->operand.i = code_data[target];
break;
}
case JVM_OPC_tableswitch:
case JVM_OPC_lookupswitch: {
/* Set the ->operand to be a table of possible instruction targets. */
int *lpc = (int *) UCALIGN(code + offset + 1);
int *lptr;
int *saved_operand;
int keys;
int k, delta;
if (context->major_version < NONZERO_PADDING_BYTES_IN_SWITCH_MAJOR_VERSION) {
/* 4639449, 4647081: Padding bytes must be zero. */
unsigned char* bptr = (unsigned char*) (code + offset + 1);
for (; bptr < (unsigned char*)lpc; bptr++) {
if (*bptr != 0) {
CCerror(context, "Non zero padding bytes in switch");
}
}
}
if (opcode == JVM_OPC_tableswitch) {
keys = _ck_ntohl(lpc[2]) - _ck_ntohl(lpc[1]) + 1;
delta = 1;
} else {
keys = _ck_ntohl(lpc[1]); /* number of pairs */
delta = 2;
/* Make sure that the tableswitch items are sorted */
for (k = keys - 1, lptr = &lpc[2]; --k >= 0; lptr += 2) {
int this_key = _ck_ntohl(lptr[0]); /* NB: ntohl may be unsigned */
int next_key = _ck_ntohl(lptr[2]);
if (this_key >= next_key) {
CCerror(context, "Unsorted lookup switch");
}
}
}
saved_operand = NEW(int, keys + 2);
if (!isLegalTarget(context, offset + _ck_ntohl(lpc[0])))
CCerror(context, "Illegal default target in switch");
saved_operand[keys + 1] = code_data[offset + _ck_ntohl(lpc[0])];
for (k = keys, lptr = &lpc[3]; --k >= 0; lptr += delta) {
int target = offset + _ck_ntohl(lptr[0]);
if (!isLegalTarget(context, target))
CCerror(context, "Illegal branch in tableswitch");
saved_operand[k + 1] = code_data[target];
}
saved_operand[0] = keys + 1; /* number of successors */
this_idata->operand.ip = saved_operand;
break;
}
case JVM_OPC_ldc: {
/* Make sure the constant pool item is the right type. */
int key = code[offset + 1];
int types = (1 << JVM_CONSTANT_Integer) | (1 << JVM_CONSTANT_Float) |
(1 << JVM_CONSTANT_String);
if (context->major_version >= LDC_CLASS_MAJOR_VERSION) {
types |= 1 << JVM_CONSTANT_Class;
}
if (context->major_version >= LDC_METHOD_HANDLE_MAJOR_VERSION) {
types |= (1 << JVM_CONSTANT_MethodHandle) |
(1 << JVM_CONSTANT_MethodType);
}
this_idata->operand.i = key;
verify_constant_pool_type(context, key, types);
break;
}
case JVM_OPC_ldc_w: {
/* Make sure the constant pool item is the right type. */
int key = (code[offset + 1] << 8) + code[offset + 2];
int types = (1 << JVM_CONSTANT_Integer) | (1 << JVM_CONSTANT_Float) |
(1 << JVM_CONSTANT_String);
if (context->major_version >= LDC_CLASS_MAJOR_VERSION) {
types |= 1 << JVM_CONSTANT_Class;
}
if (context->major_version >= LDC_METHOD_HANDLE_MAJOR_VERSION) {
types |= (1 << JVM_CONSTANT_MethodHandle) |
(1 << JVM_CONSTANT_MethodType);
}
this_idata->operand.i = key;
verify_constant_pool_type(context, key, types);
break;
}
case JVM_OPC_ldc2_w: {
/* Make sure the constant pool item is the right type. */
int key = (code[offset + 1] << 8) + code[offset + 2];
int types = (1 << JVM_CONSTANT_Double) | (1 << JVM_CONSTANT_Long);
this_idata->operand.i = key;
verify_constant_pool_type(context, key, types);
break;
}
case JVM_OPC_getfield: case JVM_OPC_putfield:
case JVM_OPC_getstatic: case JVM_OPC_putstatic: {
/* Make sure the constant pool item is the right type. */
int key = (code[offset + 1] << 8) + code[offset + 2];
this_idata->operand.i = key;
verify_constant_pool_type(context, key, 1 << JVM_CONSTANT_Fieldref);
if (opcode == JVM_OPC_getfield || opcode == JVM_OPC_putfield)
set_protected(context, inumber, key, opcode);
break;
}
case JVM_OPC_invokevirtual:
case JVM_OPC_invokespecial:
case JVM_OPC_invokestatic:
case JVM_OPC_invokeinterface: {
/* Make sure the constant pool item is the right type. */
int key = (code[offset + 1] << 8) + code[offset + 2];
const char *methodname;
jclass cb = context->class;
fullinfo_type clazz_info;
int is_constructor, is_internal;
int kind;
switch (opcode ) {
case JVM_OPC_invokestatic:
kind = ((context->major_version < STATIC_METHOD_IN_INTERFACE_MAJOR_VERSION)
? (1 << JVM_CONSTANT_Methodref)
: ((1 << JVM_CONSTANT_InterfaceMethodref) | (1 << JVM_CONSTANT_Methodref)));
break;
case JVM_OPC_invokeinterface:
kind = 1 << JVM_CONSTANT_InterfaceMethodref;
break;
default:
kind = 1 << JVM_CONSTANT_Methodref;
}
/* Make sure the constant pool item is the right type. */
verify_constant_pool_type(context, key, kind);
methodname = JVM_GetCPMethodNameUTF(env, cb, key);
check_and_push(context, methodname, VM_STRING_UTF);
is_constructor = !strcmp(methodname, "<init>");
is_internal = methodname[0] == '<';
pop_and_free(context);
clazz_info = cp_index_to_class_fullinfo(context, key,
JVM_CONSTANT_Methodref);
this_idata->operand.i = key;
this_idata->operand2.fi = clazz_info;
if (is_constructor) {
if (opcode != JVM_OPC_invokespecial) {
CCerror(context,
"Must call initializers using invokespecial");
}
this_idata->opcode = JVM_OPC_invokeinit;
} else {
if (is_internal) {
CCerror(context, "Illegal call to internal method");
}
if (opcode == JVM_OPC_invokespecial
&& clazz_info != context->currentclass_info
&& clazz_info != context->superclass_info) {
int not_found = 1;
jclass super = (*env)->GetSuperclass(env, context->class);
while(super != 0) {
jclass tmp_cb;
fullinfo_type new_info = make_class_info(context, super);
if (clazz_info == new_info) {
not_found = 0;
break;
}
tmp_cb = (*env)->GetSuperclass(env, super);
(*env)->DeleteLocalRef(env, super);
super = tmp_cb;
}
(*env)->DeleteLocalRef(env, super);
/* The optimizer may cause this to happen on local code */
if (not_found) {
CCerror(context, "Illegal use of nonvirtual function call");
}
}
}
if (opcode == JVM_OPC_invokeinterface) {
unsigned int args1;
unsigned int args2;
const char *signature =
JVM_GetCPMethodSignatureUTF(env, context->class, key);
check_and_push(context, signature, VM_STRING_UTF);
args1 = signature_to_args_size(signature) + 1;
args2 = code[offset + 3];
if (args1 != args2) {
CCerror(context,
"Inconsistent args_size for invokeinterface");
}
if (code[offset + 4] != 0) {
CCerror(context,
"Fourth operand byte of invokeinterface must be zero");
}
pop_and_free(context);
} else if (opcode == JVM_OPC_invokevirtual
|| opcode == JVM_OPC_invokespecial)
set_protected(context, inumber, key, opcode);
break;
}
case JVM_OPC_invokedynamic:
CCerror(context,
"invokedynamic bytecode is not supported in this class file version");
break;
case JVM_OPC_instanceof:
case JVM_OPC_checkcast:
case JVM_OPC_new:
case JVM_OPC_anewarray:
case JVM_OPC_multianewarray: {
/* Make sure the constant pool item is a class */
int key = (code[offset + 1] << 8) + code[offset + 2];
fullinfo_type target;
verify_constant_pool_type(context, key, 1 << JVM_CONSTANT_Class);
target = cp_index_to_class_fullinfo(context, key, JVM_CONSTANT_Class);
if (GET_ITEM_TYPE(target) == ITEM_Bogus)
CCerror(context, "Illegal type");
switch(opcode) {
case JVM_OPC_anewarray:
if ((GET_INDIRECTION(target)) >= MAX_ARRAY_DIMENSIONS)
CCerror(context, "Array with too many dimensions");
this_idata->operand.fi = MAKE_FULLINFO(GET_ITEM_TYPE(target),
GET_INDIRECTION(target) + 1,
GET_EXTRA_INFO(target));
break;
case JVM_OPC_new:
if (WITH_ZERO_EXTRA_INFO(target) !=
MAKE_FULLINFO(ITEM_Object, 0, 0))
CCerror(context, "Illegal creation of multi-dimensional array");
/* operand gets set to the "unitialized object". operand2 gets
* set to what the value will be after it's initialized. */
this_idata->operand.fi = MAKE_FULLINFO(ITEM_NewObject, 0, inumber);
this_idata->operand2.fi = target;
break;
case JVM_OPC_multianewarray:
this_idata->operand.fi = target;
this_idata->operand2.i = code[offset + 3];
if ( (this_idata->operand2.i > (int)GET_INDIRECTION(target))
|| (this_idata->operand2.i == 0))
CCerror(context, "Illegal dimension argument");
break;
default:
this_idata->operand.fi = target;
}
break;
}
case JVM_OPC_newarray: {
/* Cache the result of the JVM_OPC_newarray into the operand slot */
fullinfo_type full_info;
switch (code[offset + 1]) {
case JVM_T_INT:
full_info = MAKE_FULLINFO(ITEM_Integer, 1, 0); break;
case JVM_T_LONG:
full_info = MAKE_FULLINFO(ITEM_Long, 1, 0); break;
case JVM_T_FLOAT:
full_info = MAKE_FULLINFO(ITEM_Float, 1, 0); break;
case JVM_T_DOUBLE:
full_info = MAKE_FULLINFO(ITEM_Double, 1, 0); break;
case JVM_T_BOOLEAN:
full_info = MAKE_FULLINFO(ITEM_Boolean, 1, 0); break;
case JVM_T_BYTE:
full_info = MAKE_FULLINFO(ITEM_Byte, 1, 0); break;
case JVM_T_CHAR:
full_info = MAKE_FULLINFO(ITEM_Char, 1, 0); break;
case JVM_T_SHORT:
full_info = MAKE_FULLINFO(ITEM_Short, 1, 0); break;
default:
full_info = 0; /* Keep lint happy */
CCerror(context, "Bad type passed to newarray");
}
this_idata->operand.fi = full_info;
break;
}
/* Fudge iload_x, aload_x, etc to look like their generic cousin. */
case JVM_OPC_iload_0: case JVM_OPC_iload_1: case JVM_OPC_iload_2: case JVM_OPC_iload_3:
this_idata->opcode = JVM_OPC_iload;
var = opcode - JVM_OPC_iload_0;
goto check_local_variable;
case JVM_OPC_fload_0: case JVM_OPC_fload_1: case JVM_OPC_fload_2: case JVM_OPC_fload_3:
this_idata->opcode = JVM_OPC_fload;
var = opcode - JVM_OPC_fload_0;
goto check_local_variable;
case JVM_OPC_aload_0: case JVM_OPC_aload_1: case JVM_OPC_aload_2: case JVM_OPC_aload_3:
this_idata->opcode = JVM_OPC_aload;
var = opcode - JVM_OPC_aload_0;
goto check_local_variable;
case JVM_OPC_lload_0: case JVM_OPC_lload_1: case JVM_OPC_lload_2: case JVM_OPC_lload_3:
this_idata->opcode = JVM_OPC_lload;
var = opcode - JVM_OPC_lload_0;
goto check_local_variable2;
case JVM_OPC_dload_0: case JVM_OPC_dload_1: case JVM_OPC_dload_2: case JVM_OPC_dload_3:
this_idata->opcode = JVM_OPC_dload;
var = opcode - JVM_OPC_dload_0;
goto check_local_variable2;
case JVM_OPC_istore_0: case JVM_OPC_istore_1: case JVM_OPC_istore_2: case JVM_OPC_istore_3:
this_idata->opcode = JVM_OPC_istore;
var = opcode - JVM_OPC_istore_0;
goto check_local_variable;
case JVM_OPC_fstore_0: case JVM_OPC_fstore_1: case JVM_OPC_fstore_2: case JVM_OPC_fstore_3:
this_idata->opcode = JVM_OPC_fstore;
var = opcode - JVM_OPC_fstore_0;
goto check_local_variable;
case JVM_OPC_astore_0: case JVM_OPC_astore_1: case JVM_OPC_astore_2: case JVM_OPC_astore_3:
this_idata->opcode = JVM_OPC_astore;
var = opcode - JVM_OPC_astore_0;
goto check_local_variable;
case JVM_OPC_lstore_0: case JVM_OPC_lstore_1: case JVM_OPC_lstore_2: case JVM_OPC_lstore_3:
this_idata->opcode = JVM_OPC_lstore;
var = opcode - JVM_OPC_lstore_0;
goto check_local_variable2;
case JVM_OPC_dstore_0: case JVM_OPC_dstore_1: case JVM_OPC_dstore_2: case JVM_OPC_dstore_3:
this_idata->opcode = JVM_OPC_dstore;
var = opcode - JVM_OPC_dstore_0;
goto check_local_variable2;
case JVM_OPC_wide:
this_idata->opcode = code[offset + 1];
var = (code[offset + 2] << 8) + code[offset + 3];
switch(this_idata->opcode) {
case JVM_OPC_lload: case JVM_OPC_dload:
case JVM_OPC_lstore: case JVM_OPC_dstore:
goto check_local_variable2;
default:
goto check_local_variable;
}
case JVM_OPC_iinc: /* the increment amount doesn't matter */
case JVM_OPC_ret:
case JVM_OPC_aload: case JVM_OPC_iload: case JVM_OPC_fload:
case JVM_OPC_astore: case JVM_OPC_istore: case JVM_OPC_fstore:
var = code[offset + 1];
check_local_variable:
/* Make sure that the variable number isn't illegal. */
this_idata->operand.i = var;
if (var >= JVM_GetMethodIxLocalsCount(env, context->class, mi))
CCerror(context, "Illegal local variable number");
break;
case JVM_OPC_lload: case JVM_OPC_dload: case JVM_OPC_lstore: case JVM_OPC_dstore:
var = code[offset + 1];
check_local_variable2:
/* Make sure that the variable number isn't illegal. */
this_idata->operand.i = var;
if ((var + 1) >= JVM_GetMethodIxLocalsCount(env, context->class, mi))
CCerror(context, "Illegal local variable number");
break;
default:
if (opcode > JVM_OPC_MAX)
CCerror(context, "Quick instructions shouldn't appear yet.");
break;
} /* of switch */
}
static void
set_protected(context_type *context, unsigned int inumber, int key, int opcode)
{
JNIEnv *env = context->env;
fullinfo_type clazz_info;
if (opcode != JVM_OPC_invokevirtual && opcode != JVM_OPC_invokespecial) {
clazz_info = cp_index_to_class_fullinfo(context, key,
JVM_CONSTANT_Fieldref);
} else {
clazz_info = cp_index_to_class_fullinfo(context, key,
JVM_CONSTANT_Methodref);
}
if (is_superclass(context, clazz_info)) {
jclass calledClass =
object_fullinfo_to_classclass(context, clazz_info);
int access;
/* 4734966: JVM_GetCPFieldModifiers() or JVM_GetCPMethodModifiers() only
searches the referenced field or method in calledClass. The following
while loop is added to search up the superclass chain to make this
symbolic resolution consistent with the field/method resolution
specified in VM spec 5.4.3. */
calledClass = (*env)->NewLocalRef(env, calledClass);
do {
jclass tmp_cb;
if (opcode != JVM_OPC_invokevirtual && opcode != JVM_OPC_invokespecial) {
access = JVM_GetCPFieldModifiers
(env, context->class, key, calledClass);
} else {
access = JVM_GetCPMethodModifiers
(env, context->class, key, calledClass);
}
if (access != -1) {
break;
}
tmp_cb = (*env)->GetSuperclass(env, calledClass);
(*env)->DeleteLocalRef(env, calledClass);
calledClass = tmp_cb;
} while (calledClass != 0);
if (access == -1) {
/* field/method not found, detected at runtime. */
} else if (access & JVM_ACC_PROTECTED) {
if (!JVM_IsSameClassPackage(env, calledClass, context->class))
context->instruction_data[inumber].protected = JNI_TRUE;
}
(*env)->DeleteLocalRef(env, calledClass);
}
}
static jboolean
is_superclass(context_type *context, fullinfo_type clazz_info) {
fullinfo_type *fptr = context->superclasses;
if (fptr == 0)
return JNI_FALSE;
for (; *fptr != 0; fptr++) {
if (*fptr == clazz_info)
return JNI_TRUE;
}
return JNI_FALSE;
}
/* Look through each item on the exception table. Each of the fields must
* refer to a legal instruction.
*/
static void
initialize_exception_table(context_type *context)
{
JNIEnv *env = context->env;
int mi = context->method_index;
struct handler_info_type *handler_info = context->handler_info;
int *code_data = context->code_data;
int code_length = context->code_length;
int max_stack_size = JVM_GetMethodIxMaxStack(env, context->class, mi);
int i = JVM_GetMethodIxExceptionTableLength(env, context->class, mi);
if (max_stack_size < 1 && i > 0) {
// If the method contains exception handlers, it must have room
// on the expression stack for the exception that the VM could push
CCerror(context, "Stack size too large");
}
for (; --i >= 0; handler_info++) {
JVM_ExceptionTableEntryType einfo;
stack_item_type *stack_item = NEW(stack_item_type, 1);
JVM_GetMethodIxExceptionTableEntry(env, context->class, mi,
i, &einfo);
if (!(einfo.start_pc < einfo.end_pc &&
einfo.start_pc >= 0 &&
isLegalTarget(context, einfo.start_pc) &&
(einfo.end_pc == code_length ||
isLegalTarget(context, einfo.end_pc)))) {
CFerror(context, "Illegal exception table range");
}
if (!((einfo.handler_pc > 0) &&
isLegalTarget(context, einfo.handler_pc))) {
CFerror(context, "Illegal exception table handler");
}
handler_info->start = code_data[einfo.start_pc];
/* einfo.end_pc may point to one byte beyond the end of bytecodes. */
handler_info->end = (einfo.end_pc == context->code_length) ?
context->instruction_count : code_data[einfo.end_pc];
handler_info->handler = code_data[einfo.handler_pc];
handler_info->stack_info.stack = stack_item;
handler_info->stack_info.stack_size = 1;
stack_item->next = NULL;
if (einfo.catchType != 0) {
const char *classname;
/* Constant pool entry type has been checked in format checker */
classname = JVM_GetCPClassNameUTF(env,
context->class,
einfo.catchType);
check_and_push(context, classname, VM_STRING_UTF);
stack_item->item = make_class_info_from_name(context, classname);
if (!isAssignableTo(context,
stack_item->item,
context->throwable_info))
CCerror(context, "catch_type not a subclass of Throwable");
pop_and_free(context);
} else {
stack_item->item = context->throwable_info;
}
}
}
/* Given a pointer to an instruction, return its length. Use the table
* opcode_length[] which is automatically built.
*/
static int instruction_length(unsigned char *iptr, unsigned char *end)
{
static unsigned char opcode_length[] = JVM_OPCODE_LENGTH_INITIALIZER;
int instruction = *iptr;
switch (instruction) {
case JVM_OPC_tableswitch: {
int *lpc = (int *)UCALIGN(iptr + 1);
int index;
if (lpc + 2 >= (int *)end) {
return -1; /* do not read pass the end */
}
index = _ck_ntohl(lpc[2]) - _ck_ntohl(lpc[1]);
if ((index < 0) || (index > 65535)) {
return -1; /* illegal */
} else {
unsigned char *finish = (unsigned char *)(&lpc[index + 4]);
assert(finish >= iptr);
return (int)(finish - iptr);
}
}
case JVM_OPC_lookupswitch: {
int *lpc = (int *) UCALIGN(iptr + 1);
int npairs;
if (lpc + 1 >= (int *)end)
return -1; /* do not read pass the end */
npairs = _ck_ntohl(lpc[1]);
/* There can't be more than 64K labels because of the limit
* on per-method byte code length.
*/
if (npairs < 0 || npairs >= 65536)
return -1;
else {
unsigned char *finish = (unsigned char *)(&lpc[2 * (npairs + 1)]);
assert(finish >= iptr);
return (int)(finish - iptr);
}
}
case JVM_OPC_wide:
if (iptr + 1 >= end)
return -1; /* do not read pass the end */
switch(iptr[1]) {
case JVM_OPC_ret:
case JVM_OPC_iload: case JVM_OPC_istore:
case JVM_OPC_fload: case JVM_OPC_fstore:
case JVM_OPC_aload: case JVM_OPC_astore:
case JVM_OPC_lload: case JVM_OPC_lstore:
case JVM_OPC_dload: case JVM_OPC_dstore:
return 4;
case JVM_OPC_iinc:
return 6;
default:
return -1;
}
default: {
if (instruction < 0 || instruction > JVM_OPC_MAX)
return -1;
/* A length of 0 indicates an error. */
if (opcode_length[instruction] <= 0)
return -1;
return opcode_length[instruction];
}
}
}
/* Given the target of a branch, make sure that it's a legal target. */
static jboolean
isLegalTarget(context_type *context, int offset)
{
int code_length = context->code_length;
int *code_data = context->code_data;
return (offset >= 0 && offset < code_length && code_data[offset] >= 0);
}
/* Make sure that an element of the constant pool really is of the indicated
* type.
*/
static void
verify_constant_pool_type(context_type *context, int index, unsigned mask)
{
int nconstants = context->nconstants;
unsigned char *type_table = context->constant_types;
unsigned type;
if ((index <= 0) || (index >= nconstants))
CCerror(context, "Illegal constant pool index");
type = type_table[index];
if ((mask & (1 << type)) == 0)
CCerror(context, "Illegal type in constant pool");
}
static void
initialize_dataflow(context_type *context)
{
JNIEnv *env = context->env;
instruction_data_type *idata = context->instruction_data;
int mi = context->method_index;
jclass cb = context->class;
int args_size = JVM_GetMethodIxArgsSize(env, cb, mi);
fullinfo_type *reg_ptr;
fullinfo_type full_info;
const char *p;
const char *signature;
/* Initialize the function entry, since we know everything about it. */
idata[0].stack_info.stack_size = 0;
idata[0].stack_info.stack = NULL;
idata[0].register_info.register_count = args_size;
idata[0].register_info.registers = NEW(fullinfo_type, args_size);
idata[0].register_info.mask_count = 0;
idata[0].register_info.masks = NULL;
idata[0].and_flags = 0; /* nothing needed */
idata[0].or_flags = FLAG_REACHED; /* instruction reached */
reg_ptr = idata[0].register_info.registers;
if ((JVM_GetMethodIxModifiers(env, cb, mi) & JVM_ACC_STATIC) == 0) {
/* A non static method. If this is an <init> method, the first
* argument is an uninitialized object. Otherwise it is an object of
* the given class type. java.lang.Object.<init> is special since
* we don't call its superclass <init> method.
*/
if (JVM_IsConstructorIx(env, cb, mi)
&& context->currentclass_info != context->object_info) {
*reg_ptr++ = MAKE_FULLINFO(ITEM_InitObject, 0, 0);
idata[0].or_flags |= FLAG_NEED_CONSTRUCTOR;
} else {
*reg_ptr++ = context->currentclass_info;
}
}
signature = JVM_GetMethodIxSignatureUTF(env, cb, mi);
check_and_push(context, signature, VM_STRING_UTF);
/* Fill in each of the arguments into the registers. */
for (p = signature + 1; *p != JVM_SIGNATURE_ENDFUNC; ) {
char fieldchar = signature_to_fieldtype(context, &p, &full_info);
switch (fieldchar) {
case 'D': case 'L':
*reg_ptr++ = full_info;
*reg_ptr++ = full_info + 1;
break;
default:
*reg_ptr++ = full_info;
break;
}
}
p++; /* skip over right parenthesis */
if (*p == 'V') {
context->return_type = MAKE_FULLINFO(ITEM_Void, 0, 0);
} else {
signature_to_fieldtype(context, &p, &full_info);
context->return_type = full_info;
}
pop_and_free(context);
/* Indicate that we need to look at the first instruction. */
idata[0].changed = JNI_TRUE;
}
/* Run the data flow analysis, as long as there are things to change. */
static void
run_dataflow(context_type *context) {
JNIEnv *env = context->env;
int mi = context->method_index;
jclass cb = context->class;
int max_stack_size = JVM_GetMethodIxMaxStack(env, cb, mi);
instruction_data_type *idata = context->instruction_data;
unsigned int icount = context->instruction_count;
jboolean work_to_do = JNI_TRUE;
unsigned int inumber;
/* Run through the loop, until there is nothing left to do. */
while (work_to_do) {
work_to_do = JNI_FALSE;
for (inumber = 0; inumber < icount; inumber++) {
instruction_data_type *this_idata = &idata[inumber];
if (this_idata->changed) {
register_info_type new_register_info;
stack_info_type new_stack_info;
flag_type new_and_flags, new_or_flags;
this_idata->changed = JNI_FALSE;
work_to_do = JNI_TRUE;
#ifdef DEBUG
if (verify_verbose) {
int opcode = this_idata->opcode;
jio_fprintf(stdout, "Instruction %d: ", inumber);
print_stack(context, &this_idata->stack_info);
print_registers(context, &this_idata->register_info);
print_flags(context,
this_idata->and_flags, this_idata->or_flags);
fflush(stdout);
}
#endif
/* Make sure the registers and flags are appropriate */
check_register_values(context, inumber);
check_flags(context, inumber);
/* Make sure the stack can deal with this instruction */
pop_stack(context, inumber, &new_stack_info);
/* Update the registers and flags */
update_registers(context, inumber, &new_register_info);
update_flags(context, inumber, &new_and_flags, &new_or_flags);
/* Update the stack. */
push_stack(context, inumber, &new_stack_info);
if (new_stack_info.stack_size > max_stack_size)
CCerror(context, "Stack size too large");
#ifdef DEBUG
if (verify_verbose) {
jio_fprintf(stdout, " ");
print_stack(context, &new_stack_info);
print_registers(context, &new_register_info);
print_flags(context, new_and_flags, new_or_flags);
fflush(stdout);
}
#endif
/* Add the new stack and register information to any
* instructions that can follow this instruction. */
merge_into_successors(context, inumber,
&new_register_info, &new_stack_info,
new_and_flags, new_or_flags);
}
}
}
}
/* Make sure that the registers contain a legitimate value for the given
* instruction.
*/
static void
check_register_values(context_type *context, unsigned int inumber)
{
instruction_data_type *idata = context->instruction_data;
instruction_data_type *this_idata = &idata[inumber];
int opcode = this_idata->opcode;
int operand = this_idata->operand.i;
int register_count = this_idata->register_info.register_count;
fullinfo_type *registers = this_idata->register_info.registers;
jboolean double_word = JNI_FALSE; /* default value */
int type;
switch (opcode) {
default:
return;
case JVM_OPC_iload: case JVM_OPC_iinc:
type = ITEM_Integer; break;
case JVM_OPC_fload:
type = ITEM_Float; break;
case JVM_OPC_aload:
type = ITEM_Object; break;
case JVM_OPC_ret:
type = ITEM_ReturnAddress; break;
case JVM_OPC_lload:
type = ITEM_Long; double_word = JNI_TRUE; break;
case JVM_OPC_dload:
type = ITEM_Double; double_word = JNI_TRUE; break;
}
if (!double_word) {
fullinfo_type reg;
/* Make sure we don't have an illegal register or one with wrong type */
if (operand >= register_count) {
CCerror(context,
"Accessing value from uninitialized register %d", operand);
}
reg = registers[operand];
if (WITH_ZERO_EXTRA_INFO(reg) == (unsigned)MAKE_FULLINFO(type, 0, 0)) {
/* the register is obviously of the given type */
return;
} else if (GET_INDIRECTION(reg) > 0 && type == ITEM_Object) {
/* address type stuff be used on all arrays */
return;
} else if (GET_ITEM_TYPE(reg) == ITEM_ReturnAddress) {
CCerror(context, "Cannot load return address from register %d",
operand);
/* alternatively
(GET_ITEM_TYPE(reg) == ITEM_ReturnAddress)
&& (opcode == JVM_OPC_iload)
&& (type == ITEM_Object || type == ITEM_Integer)
but this never occurs
*/
} else if (reg == ITEM_InitObject && type == ITEM_Object) {
return;
} else if (WITH_ZERO_EXTRA_INFO(reg) ==
MAKE_FULLINFO(ITEM_NewObject, 0, 0) &&
type == ITEM_Object) {
return;
} else {
CCerror(context, "Register %d contains wrong type", operand);
}
} else {
/* Make sure we don't have an illegal register or one with wrong type */
if ((operand + 1) >= register_count) {
CCerror(context,
"Accessing value from uninitialized register pair %d/%d",
operand, operand+1);
} else {
if ((registers[operand] == (unsigned)MAKE_FULLINFO(type, 0, 0)) &&
(registers[operand + 1] == (unsigned)MAKE_FULLINFO(type + 1, 0, 0))) {
return;
} else {
CCerror(context, "Register pair %d/%d contains wrong type",
operand, operand+1);
}
}
}
}
/* Make sure the flags contain legitimate values for this instruction.
*/
static void
check_flags(context_type *context, unsigned int inumber)
{
instruction_data_type *idata = context->instruction_data;
instruction_data_type *this_idata = &idata[inumber];
int opcode = this_idata->opcode;
switch (opcode) {
case JVM_OPC_return:
/* We need a constructor, but we aren't guaranteed it's called */
if ((this_idata->or_flags & FLAG_NEED_CONSTRUCTOR) &&
!(this_idata->and_flags & FLAG_CONSTRUCTED))
CCerror(context, "Constructor must call super() or this()");
/* fall through */
case JVM_OPC_ireturn: case JVM_OPC_lreturn:
case JVM_OPC_freturn: case JVM_OPC_dreturn: case JVM_OPC_areturn:
if (this_idata->or_flags & FLAG_NO_RETURN)
/* This method cannot exit normally */
CCerror(context, "Cannot return normally");
default:
break; /* nothing to do. */
}
}
/* Make sure that the top of the stack contains reasonable values for the
* given instruction. The post-pop values of the stack and its size are
* returned in *new_stack_info.
*/
static void
pop_stack(context_type *context, unsigned int inumber, stack_info_type *new_stack_info)
{
instruction_data_type *idata = context->instruction_data;
instruction_data_type *this_idata = &idata[inumber];
int opcode = this_idata->opcode;
stack_item_type *stack = this_idata->stack_info.stack;
int stack_size = this_idata->stack_info.stack_size;
char *stack_operands, *p;
char buffer[257]; /* for holding manufactured argument lists */
fullinfo_type stack_extra_info_buffer[256]; /* save info popped off stack */
fullinfo_type *stack_extra_info = &stack_extra_info_buffer[256];
fullinfo_type full_info; /* only used in case of invoke instructions */
fullinfo_type put_full_info; /* only used in case JVM_OPC_putstatic and JVM_OPC_putfield */
switch(opcode) {
default:
/* For most instructions, we just use a built-in table */
stack_operands = opcode_in_out[opcode][0];
break;
case JVM_OPC_putstatic: case JVM_OPC_putfield: {
/* The top thing on the stack depends on the signature of
* the object. */
int operand = this_idata->operand.i;
const char *signature =
JVM_GetCPFieldSignatureUTF(context->env,
context->class,
operand);
char *ip = buffer;
check_and_push(context, signature, VM_STRING_UTF);
#ifdef DEBUG
if (verify_verbose) {
print_formatted_fieldname(context, operand);
}
#endif
if (opcode == JVM_OPC_putfield)
*ip++ = 'A'; /* object for putfield */
*ip++ = signature_to_fieldtype(context, &signature, &put_full_info);
*ip = '\0';
stack_operands = buffer;
pop_and_free(context);
break;
}
case JVM_OPC_invokevirtual: case JVM_OPC_invokespecial:
case JVM_OPC_invokeinit: /* invokespecial call to <init> */
case JVM_OPC_invokestatic: case JVM_OPC_invokeinterface: {
/* The top stuff on the stack depends on the method signature */
int operand = this_idata->operand.i;
const char *signature =
JVM_GetCPMethodSignatureUTF(context->env,
context->class,
operand);
char *ip = buffer;
const char *p;
check_and_push(context, signature, VM_STRING_UTF);
#ifdef DEBUG
if (verify_verbose) {
print_formatted_methodname(context, operand);
}
#endif
if (opcode != JVM_OPC_invokestatic)
/* First, push the object */
*ip++ = (opcode == JVM_OPC_invokeinit ? '@' : 'A');
for (p = signature + 1; *p != JVM_SIGNATURE_ENDFUNC; ) {
*ip++ = signature_to_fieldtype(context, &p, &full_info);
if (ip >= buffer + sizeof(buffer) - 1)
CCerror(context, "Signature %s has too many arguments",
signature);
}
*ip = 0;
stack_operands = buffer;
pop_and_free(context);
break;
}
case JVM_OPC_multianewarray: {
/* Count can't be larger than 255. So can't overflow buffer */
int count = this_idata->operand2.i; /* number of ints on stack */
memset(buffer, 'I', count);
buffer[count] = '\0';
stack_operands = buffer;
break;
}
} /* of switch */
/* Run through the list of operands >>backwards<< */
for ( p = stack_operands + strlen(stack_operands);
p > stack_operands;
stack = stack->next) {
int type = *--p;
fullinfo_type top_type = stack ? stack->item : 0;
int size = (type == 'D' || type == 'L') ? 2 : 1;
*--stack_extra_info = top_type;
if (stack == NULL)
CCerror(context, "Unable to pop operand off an empty stack");
switch (type) {
case 'I':
if (top_type != MAKE_FULLINFO(ITEM_Integer, 0, 0))
CCerror(context, "Expecting to find integer on stack");
break;
case 'F':
if (top_type != MAKE_FULLINFO(ITEM_Float, 0, 0))
CCerror(context, "Expecting to find float on stack");
break;
case 'A': /* object or array */
if ( (GET_ITEM_TYPE(top_type) != ITEM_Object)
&& (GET_INDIRECTION(top_type) == 0)) {
/* The thing isn't an object or an array. Let's see if it's
* one of the special cases */
if ( (WITH_ZERO_EXTRA_INFO(top_type) ==
MAKE_FULLINFO(ITEM_ReturnAddress, 0, 0))
&& (opcode == JVM_OPC_astore))
break;
if ( (GET_ITEM_TYPE(top_type) == ITEM_NewObject
|| (GET_ITEM_TYPE(top_type) == ITEM_InitObject))
&& ((opcode == JVM_OPC_astore) || (opcode == JVM_OPC_aload)
|| (opcode == JVM_OPC_ifnull) || (opcode == JVM_OPC_ifnonnull)))
break;
/* The 2nd edition VM of the specification allows field
* initializations before the superclass initializer,
* if the field is defined within the current class.
*/
if ( (GET_ITEM_TYPE(top_type) == ITEM_InitObject)
&& (opcode == JVM_OPC_putfield)) {
int operand = this_idata->operand.i;
int access_bits = JVM_GetCPFieldModifiers(context->env,
context->class,
operand,
context->class);
/* Note: This relies on the fact that
* JVM_GetCPFieldModifiers retrieves only local fields,
* and does not respect inheritance.
*/
if (access_bits != -1) {
if ( cp_index_to_class_fullinfo(context, operand, JVM_CONSTANT_Fieldref) ==
context->currentclass_info ) {
top_type = context->currentclass_info;
*stack_extra_info = top_type;
break;
}
}
}
CCerror(context, "Expecting to find object/array on stack");
}
break;
case '@': { /* unitialized object, for call to <init> */
int item_type = GET_ITEM_TYPE(top_type);
if (item_type != ITEM_NewObject && item_type != ITEM_InitObject)
CCerror(context,
"Expecting to find unitialized object on stack");
break;
}
case 'O': /* object, not array */
if (WITH_ZERO_EXTRA_INFO(top_type) !=
MAKE_FULLINFO(ITEM_Object, 0, 0))
CCerror(context, "Expecting to find object on stack");
break;
case 'a': /* integer, object, or array */
if ( (top_type != MAKE_FULLINFO(ITEM_Integer, 0, 0))
&& (GET_ITEM_TYPE(top_type) != ITEM_Object)
&& (GET_INDIRECTION(top_type) == 0))
CCerror(context,
"Expecting to find object, array, or int on stack");
break;
case 'D': /* double */
if (top_type != MAKE_FULLINFO(ITEM_Double, 0, 0))
CCerror(context, "Expecting to find double on stack");
break;
case 'L': /* long */
if (top_type != MAKE_FULLINFO(ITEM_Long, 0, 0))
CCerror(context, "Expecting to find long on stack");
break;
case ']': /* array of some type */
if (top_type == NULL_FULLINFO) {
/* do nothing */
} else switch(p[-1]) {
case 'I': /* array of integers */
if (top_type != MAKE_FULLINFO(ITEM_Integer, 1, 0) &&
top_type != NULL_FULLINFO)
CCerror(context,
"Expecting to find array of ints on stack");
break;
case 'L': /* array of longs */
if (top_type != MAKE_FULLINFO(ITEM_Long, 1, 0))
CCerror(context,
"Expecting to find array of longs on stack");
break;
case 'F': /* array of floats */
if (top_type != MAKE_FULLINFO(ITEM_Float, 1, 0))
CCerror(context,
"Expecting to find array of floats on stack");
break;
case 'D': /* array of doubles */
if (top_type != MAKE_FULLINFO(ITEM_Double, 1, 0))
CCerror(context,
"Expecting to find array of doubles on stack");
break;
case 'A': { /* array of addresses (arrays or objects) */
int indirection = GET_INDIRECTION(top_type);
if ((indirection == 0) ||
((indirection == 1) &&
(GET_ITEM_TYPE(top_type) != ITEM_Object)))
CCerror(context,
"Expecting to find array of objects or arrays "
"on stack");
break;
}
case 'B': /* array of bytes or booleans */
if (top_type != MAKE_FULLINFO(ITEM_Byte, 1, 0) &&
top_type != MAKE_FULLINFO(ITEM_Boolean, 1, 0))
CCerror(context,
"Expecting to find array of bytes or Booleans on stack");
break;
case 'C': /* array of characters */
if (top_type != MAKE_FULLINFO(ITEM_Char, 1, 0))
CCerror(context,
"Expecting to find array of chars on stack");
break;
case 'S': /* array of shorts */
if (top_type != MAKE_FULLINFO(ITEM_Short, 1, 0))
CCerror(context,
"Expecting to find array of shorts on stack");
break;
case '?': /* any type of array is okay */
if (GET_INDIRECTION(top_type) == 0)
CCerror(context,
"Expecting to find array on stack");
break;
default:
CCerror(context, "Internal error #1");
break;
}
p -= 2; /* skip over [ <char> */
break;
case '1': case '2': case '3': case '4': /* stack swapping */
if (top_type == MAKE_FULLINFO(ITEM_Double, 0, 0)
|| top_type == MAKE_FULLINFO(ITEM_Long, 0, 0)) {
if ((p > stack_operands) && (p[-1] == '+')) {
context->swap_table[type - '1'] = top_type + 1;
context->swap_table[p[-2] - '1'] = top_type;
size = 2;
p -= 2;
} else {
CCerror(context,
"Attempt to split long or double on the stack");
}
} else {
context->swap_table[type - '1'] = stack->item;
if ((p > stack_operands) && (p[-1] == '+'))
p--; /* ignore */
}
break;
case '+': /* these should have been caught. */
default:
CCerror(context, "Internal error #2");
}
stack_size -= size;
}
/* For many of the opcodes that had an "A" in their field, we really
* need to go back and do a little bit more accurate testing. We can, of
* course, assume that the minimal type checking has already been done.
*/
switch (opcode) {
default: break;
case JVM_OPC_aastore: { /* array index object */
fullinfo_type array_type = stack_extra_info[0];
fullinfo_type object_type = stack_extra_info[2];
fullinfo_type target_type = decrement_indirection(array_type);
if ((GET_ITEM_TYPE(object_type) != ITEM_Object)
&& (GET_INDIRECTION(object_type) == 0)) {
CCerror(context, "Expecting reference type on operand stack in aastore");
}
if ((GET_ITEM_TYPE(target_type) != ITEM_Object)
&& (GET_INDIRECTION(target_type) == 0)) {
CCerror(context, "Component type of the array must be reference type in aastore");
}
break;
}
case JVM_OPC_putfield:
case JVM_OPC_getfield:
case JVM_OPC_putstatic: {
int operand = this_idata->operand.i;
fullinfo_type stack_object = stack_extra_info[0];
if (opcode == JVM_OPC_putfield || opcode == JVM_OPC_getfield) {
if (!isAssignableTo
(context,
stack_object,
cp_index_to_class_fullinfo
(context, operand, JVM_CONSTANT_Fieldref))) {
CCerror(context,
"Incompatible type for getting or setting field");
}
if (this_idata->protected &&
!isAssignableTo(context, stack_object,
context->currentclass_info)) {
CCerror(context, "Bad access to protected data");
}
}
if (opcode == JVM_OPC_putfield || opcode == JVM_OPC_putstatic) {
int item = (opcode == JVM_OPC_putfield ? 1 : 0);
if (!isAssignableTo(context,
stack_extra_info[item], put_full_info)) {
CCerror(context, "Bad type in putfield/putstatic");
}
}
break;
}
case JVM_OPC_athrow:
if (!isAssignableTo(context, stack_extra_info[0],
context->throwable_info)) {
CCerror(context, "Can only throw Throwable objects");
}
break;
case JVM_OPC_aaload: { /* array index */
/* We need to pass the information to the stack updater */
fullinfo_type array_type = stack_extra_info[0];
context->swap_table[0] = decrement_indirection(array_type);
break;
}
case JVM_OPC_invokevirtual: case JVM_OPC_invokespecial:
case JVM_OPC_invokeinit:
case JVM_OPC_invokeinterface: case JVM_OPC_invokestatic: {
int operand = this_idata->operand.i;
const char *signature =
JVM_GetCPMethodSignatureUTF(context->env,
context->class,
operand);
int item;
const char *p;
check_and_push(context, signature, VM_STRING_UTF);
if (opcode == JVM_OPC_invokestatic) {
item = 0;
} else if (opcode == JVM_OPC_invokeinit) {
fullinfo_type init_type = this_idata->operand2.fi;
fullinfo_type object_type = stack_extra_info[0];
context->swap_table[0] = object_type; /* save value */
if (GET_ITEM_TYPE(stack_extra_info[0]) == ITEM_NewObject) {
/* We better be calling the appropriate init. Find the
* inumber of the "JVM_OPC_new" instruction", and figure
* out what the type really is.
*/
unsigned int new_inumber = GET_EXTRA_INFO(stack_extra_info[0]);
fullinfo_type target_type = idata[new_inumber].operand2.fi;
context->swap_table[1] = target_type;
if (target_type != init_type) {
CCerror(context, "Call to wrong initialization method");
}
if (this_idata->protected
&& !isAssignableTo(context, object_type,
context->currentclass_info)) {
CCerror(context, "Bad access to protected data");
}
} else {
/* We better be calling super() or this(). */
if (init_type != context->superclass_info &&
init_type != context->currentclass_info) {
CCerror(context, "Call to wrong initialization method");
}
context->swap_table[1] = context->currentclass_info;
}
item = 1;
} else {
fullinfo_type target_type = this_idata->operand2.fi;
fullinfo_type object_type = stack_extra_info[0];
if (!isAssignableTo(context, object_type, target_type)){
CCerror(context,
"Incompatible object argument for function call");
}
if (opcode == JVM_OPC_invokespecial
&& !isAssignableTo(context, object_type,
context->currentclass_info)) {
/* Make sure object argument is assignment compatible to current class */
CCerror(context,
"Incompatible object argument for invokespecial");
}
if (this_idata->protected
&& !isAssignableTo(context, object_type,
context->currentclass_info)) {
/* This is ugly. Special dispensation. Arrays pretend to
implement public Object clone() even though they don't */
const char *utfName =
JVM_GetCPMethodNameUTF(context->env,
context->class,
this_idata->operand.i);
int is_clone = utfName && (strcmp(utfName, "clone") == 0);
JVM_ReleaseUTF(utfName);
if ((target_type == context->object_info) &&
(GET_INDIRECTION(object_type) > 0) &&
is_clone) {
} else {
CCerror(context, "Bad access to protected data");
}
}
item = 1;
}
for (p = signature + 1; *p != JVM_SIGNATURE_ENDFUNC; item++)
if (signature_to_fieldtype(context, &p, &full_info) == 'A') {
if (!isAssignableTo(context,
stack_extra_info[item], full_info)) {
CCerror(context, "Incompatible argument to function");
}
}
pop_and_free(context);
break;
}
case JVM_OPC_return:
if (context->return_type != MAKE_FULLINFO(ITEM_Void, 0, 0))
CCerror(context, "Wrong return type in function");
break;
case JVM_OPC_ireturn: case JVM_OPC_lreturn: case JVM_OPC_freturn:
case JVM_OPC_dreturn: case JVM_OPC_areturn: {
fullinfo_type target_type = context->return_type;
fullinfo_type object_type = stack_extra_info[0];
if (!isAssignableTo(context, object_type, target_type)) {
CCerror(context, "Wrong return type in function");
}
break;
}
case JVM_OPC_new: {
/* Make sure that nothing on the stack already looks like what
* we want to create. I can't image how this could possibly happen
* but we should test for it anyway, since if it could happen, the
* result would be an unitialized object being able to masquerade
* as an initialized one.
*/
stack_item_type *item;
for (item = stack; item != NULL; item = item->next) {
if (item->item == this_idata->operand.fi) {
CCerror(context,
"Uninitialized object on stack at creating point");
}
}
/* Info for update_registers */
context->swap_table[0] = this_idata->operand.fi;
context->swap_table[1] = MAKE_FULLINFO(ITEM_Bogus, 0, 0);
break;
}
}
new_stack_info->stack = stack;
new_stack_info->stack_size = stack_size;
}
/* We've already determined that the instruction is legal. Perform the
* operation on the registers, and return the updated results in
* new_register_count_p and new_registers.
*/
static void
update_registers(context_type *context, unsigned int inumber,
register_info_type *new_register_info)
{
instruction_data_type *idata = context->instruction_data;
instruction_data_type *this_idata = &idata[inumber];
int opcode = this_idata->opcode;
int operand = this_idata->operand.i;
int register_count = this_idata->register_info.register_count;
fullinfo_type *registers = this_idata->register_info.registers;
stack_item_type *stack = this_idata->stack_info.stack;
int mask_count = this_idata->register_info.mask_count;
mask_type *masks = this_idata->register_info.masks;
/* Use these as default new values. */
int new_register_count = register_count;
int new_mask_count = mask_count;
fullinfo_type *new_registers = registers;
mask_type *new_masks = masks;
enum { ACCESS_NONE, ACCESS_SINGLE, ACCESS_DOUBLE } access = ACCESS_NONE;
int i;
/* Remember, we've already verified the type at the top of the stack. */
switch (opcode) {
default: break;
case JVM_OPC_istore: case JVM_OPC_fstore: case JVM_OPC_astore:
access = ACCESS_SINGLE;
goto continue_store;
case JVM_OPC_lstore: case JVM_OPC_dstore:
access = ACCESS_DOUBLE;
goto continue_store;
continue_store: {
/* We have a modification to the registers. Copy them if needed. */
fullinfo_type stack_top_type = stack->item;
int max_operand = operand + ((access == ACCESS_DOUBLE) ? 1 : 0);
if ( max_operand < register_count
&& registers[operand] == stack_top_type
&& ((access == ACCESS_SINGLE) ||
(registers[operand + 1]== stack_top_type + 1)))
/* No changes have been made to the registers. */
break;
new_register_count = MAX(max_operand + 1, register_count);
new_registers = NEW(fullinfo_type, new_register_count);
for (i = 0; i < register_count; i++)
new_registers[i] = registers[i];
for (i = register_count; i < new_register_count; i++)
new_registers[i] = MAKE_FULLINFO(ITEM_Bogus, 0, 0);
new_registers[operand] = stack_top_type;
if (access == ACCESS_DOUBLE)
new_registers[operand + 1] = stack_top_type + 1;
break;
}
case JVM_OPC_iload: case JVM_OPC_fload: case JVM_OPC_aload:
case JVM_OPC_iinc: case JVM_OPC_ret:
access = ACCESS_SINGLE;
break;
case JVM_OPC_lload: case JVM_OPC_dload:
access = ACCESS_DOUBLE;
break;
case JVM_OPC_jsr: case JVM_OPC_jsr_w:
for (i = 0; i < new_mask_count; i++)
if (new_masks[i].entry == operand)
CCerror(context, "Recursive call to jsr entry");
new_masks = add_to_masks(context, masks, mask_count, operand);
new_mask_count++;
break;
case JVM_OPC_invokeinit:
case JVM_OPC_new: {
/* For invokeinit, an uninitialized object has been initialized.
* For new, all previous occurrences of an uninitialized object
* from the same instruction must be made bogus.
* We find all occurrences of swap_table[0] in the registers, and
* replace them with swap_table[1];
*/
fullinfo_type from = context->swap_table[0];
fullinfo_type to = context->swap_table[1];
int i;
for (i = 0; i < register_count; i++) {
if (new_registers[i] == from) {
/* Found a match */
break;
}
}
if (i < register_count) { /* We broke out loop for match */
/* We have to change registers, and possibly a mask */
jboolean copied_mask = JNI_FALSE;
int k;
new_registers = NEW(fullinfo_type, register_count);
memcpy(new_registers, registers,
register_count * sizeof(registers[0]));
for ( ; i < register_count; i++) {
if (new_registers[i] == from) {
new_registers[i] = to;
for (k = 0; k < new_mask_count; k++) {
if (!IS_BIT_SET(new_masks[k].modifies, i)) {
if (!copied_mask) {
new_masks = copy_masks(context, new_masks,
mask_count);
copied_mask = JNI_TRUE;
}
SET_BIT(new_masks[k].modifies, i);
}
}
}
}
}
break;
}
} /* of switch */
if ((access != ACCESS_NONE) && (new_mask_count > 0)) {
int i, j;
for (i = 0; i < new_mask_count; i++) {
int *mask = new_masks[i].modifies;
if ((!IS_BIT_SET(mask, operand)) ||
((access == ACCESS_DOUBLE) &&
!IS_BIT_SET(mask, operand + 1))) {
new_masks = copy_masks(context, new_masks, mask_count);
for (j = i; j < new_mask_count; j++) {
SET_BIT(new_masks[j].modifies, operand);
if (access == ACCESS_DOUBLE)
SET_BIT(new_masks[j].modifies, operand + 1);
}
break;
}
}
}
new_register_info->register_count = new_register_count;
new_register_info->registers = new_registers;
new_register_info->masks = new_masks;
new_register_info->mask_count = new_mask_count;
}
/* We've already determined that the instruction is legal, and have updated
* the registers. Update the flags, too.
*/
static void
update_flags(context_type *context, unsigned int inumber,
flag_type *new_and_flags, flag_type *new_or_flags)
{
instruction_data_type *idata = context->instruction_data;
instruction_data_type *this_idata = &idata[inumber];
flag_type and_flags = this_idata->and_flags;
flag_type or_flags = this_idata->or_flags;
/* Set the "we've done a constructor" flag */
if (this_idata->opcode == JVM_OPC_invokeinit) {
fullinfo_type from = context->swap_table[0];
if (from == MAKE_FULLINFO(ITEM_InitObject, 0, 0))
and_flags |= FLAG_CONSTRUCTED;
}
*new_and_flags = and_flags;
*new_or_flags = or_flags;
}
/* We've already determined that the instruction is legal. Perform the
* operation on the stack;
*
* new_stack_size_p and new_stack_p point to the results after the pops have
* already been done. Do the pushes, and then put the results back there.
*/
static void
push_stack(context_type *context, unsigned int inumber, stack_info_type *new_stack_info)
{
instruction_data_type *idata = context->instruction_data;
instruction_data_type *this_idata = &idata[inumber];
int opcode = this_idata->opcode;
int operand = this_idata->operand.i;
int stack_size = new_stack_info->stack_size;
stack_item_type *stack = new_stack_info->stack;
char *stack_results;
fullinfo_type full_info = 0;
char buffer[5], *p; /* actually [2] is big enough */
/* We need to look at all those opcodes in which either we can't tell the
* value pushed onto the stack from the opcode, or in which the value
* pushed onto the stack is an object or array. For the latter, we need
* to make sure that full_info is set to the right value.
*/
switch(opcode) {
default:
stack_results = opcode_in_out[opcode][1];
break;
case JVM_OPC_ldc: case JVM_OPC_ldc_w: case JVM_OPC_ldc2_w: {
/* Look to constant pool to determine correct result. */
unsigned char *type_table = context->constant_types;
switch (type_table[operand]) {
case JVM_CONSTANT_Integer:
stack_results = "I"; break;
case JVM_CONSTANT_Float:
stack_results = "F"; break;
case JVM_CONSTANT_Double:
stack_results = "D"; break;
case JVM_CONSTANT_Long:
stack_results = "L"; break;
case JVM_CONSTANT_String:
stack_results = "A";
full_info = context->string_info;
break;
case JVM_CONSTANT_Class:
if (context->major_version < LDC_CLASS_MAJOR_VERSION)
CCerror(context, "Internal error #3");
stack_results = "A";
full_info = make_class_info_from_name(context,
"java/lang/Class");
break;
case JVM_CONSTANT_MethodHandle:
case JVM_CONSTANT_MethodType:
if (context->major_version < LDC_METHOD_HANDLE_MAJOR_VERSION)
CCerror(context, "Internal error #3");
stack_results = "A";
switch (type_table[operand]) {
case JVM_CONSTANT_MethodType:
full_info = make_class_info_from_name(context,
"java/lang/invoke/MethodType");
break;
default: //JVM_CONSTANT_MethodHandle
full_info = make_class_info_from_name(context,
"java/lang/invoke/MethodHandle");
break;
}
break;
default:
CCerror(context, "Internal error #3");
stack_results = ""; /* Never reached: keep lint happy */
}
break;
}
case JVM_OPC_getstatic: case JVM_OPC_getfield: {
/* Look to signature to determine correct result. */
int operand = this_idata->operand.i;
const char *signature = JVM_GetCPFieldSignatureUTF(context->env,
context->class,
operand);
check_and_push(context, signature, VM_STRING_UTF);
#ifdef DEBUG
if (verify_verbose) {
print_formatted_fieldname(context, operand);
}
#endif
buffer[0] = signature_to_fieldtype(context, &signature, &full_info);
buffer[1] = '\0';
stack_results = buffer;
pop_and_free(context);
break;
}
case JVM_OPC_invokevirtual: case JVM_OPC_invokespecial:
case JVM_OPC_invokeinit:
case JVM_OPC_invokestatic: case JVM_OPC_invokeinterface: {
/* Look to signature to determine correct result. */
int operand = this_idata->operand.i;
const char *signature = JVM_GetCPMethodSignatureUTF(context->env,
context->class,
operand);
const char *result_signature;
check_and_push(context, signature, VM_STRING_UTF);
result_signature = get_result_signature(signature);
if (result_signature++ == NULL) {
CCerror(context, "Illegal signature %s", signature);
}
if (result_signature[0] == JVM_SIGNATURE_VOID) {
stack_results = "";
} else {
buffer[0] = signature_to_fieldtype(context, &result_signature,
&full_info);
buffer[1] = '\0';
stack_results = buffer;
}
pop_and_free(context);
break;
}
case JVM_OPC_aconst_null:
stack_results = opcode_in_out[opcode][1];
full_info = NULL_FULLINFO; /* special NULL */
break;
case JVM_OPC_new:
case JVM_OPC_checkcast:
case JVM_OPC_newarray:
case JVM_OPC_anewarray:
case JVM_OPC_multianewarray:
stack_results = opcode_in_out[opcode][1];
/* Conveniently, this result type is stored here */
full_info = this_idata->operand.fi;
break;
case JVM_OPC_aaload:
stack_results = opcode_in_out[opcode][1];
/* pop_stack() saved value for us. */
full_info = context->swap_table[0];
break;
case JVM_OPC_aload:
stack_results = opcode_in_out[opcode][1];
/* The register hasn't been modified, so we can use its value. */
full_info = this_idata->register_info.registers[operand];
break;
} /* of switch */
for (p = stack_results; *p != 0; p++) {
int type = *p;
stack_item_type *new_item = NEW(stack_item_type, 1);
new_item->next = stack;
stack = new_item;
switch (type) {
case 'I':
stack->item = MAKE_FULLINFO(ITEM_Integer, 0, 0); break;
case 'F':
stack->item = MAKE_FULLINFO(ITEM_Float, 0, 0); break;
case 'D':
stack->item = MAKE_FULLINFO(ITEM_Double, 0, 0);
stack_size++; break;
case 'L':
stack->item = MAKE_FULLINFO(ITEM_Long, 0, 0);
stack_size++; break;
case 'R':
stack->item = MAKE_FULLINFO(ITEM_ReturnAddress, 0, operand);
break;
case '1': case '2': case '3': case '4': {
/* Get the info saved in the swap_table */
fullinfo_type stype = context->swap_table[type - '1'];
stack->item = stype;
if (stype == MAKE_FULLINFO(ITEM_Long, 0, 0) ||
stype == MAKE_FULLINFO(ITEM_Double, 0, 0)) {
stack_size++; p++;
}
break;
}
case 'A':
/* full_info should have the appropriate value. */
assert(full_info != 0);
stack->item = full_info;
break;
default:
CCerror(context, "Internal error #4");
} /* switch type */
stack_size++;
} /* outer for loop */
if (opcode == JVM_OPC_invokeinit) {
/* If there are any instances of "from" on the stack, we need to
* replace it with "to", since calling <init> initializes all versions
* of the object, obviously. */
fullinfo_type from = context->swap_table[0];
stack_item_type *ptr;
for (ptr = stack; ptr != NULL; ptr = ptr->next) {
if (ptr->item == from) {
fullinfo_type to = context->swap_table[1];
stack = copy_stack(context, stack);
for (ptr = stack; ptr != NULL; ptr = ptr->next)
if (ptr->item == from) ptr->item = to;
break;
}
}
}
new_stack_info->stack_size = stack_size;
new_stack_info->stack = stack;
}
/* We've performed an instruction, and determined the new registers and stack
* value. Look at all of the possibly subsequent instructions, and merge
* this stack value into theirs.
*/
static void
merge_into_successors(context_type *context, unsigned int inumber,
register_info_type *register_info,
stack_info_type *stack_info,
flag_type and_flags, flag_type or_flags)
{
instruction_data_type *idata = context->instruction_data;
instruction_data_type *this_idata = &idata[inumber];
int opcode = this_idata->opcode;
int operand = this_idata->operand.i;
struct handler_info_type *handler_info = context->handler_info;
int handler_info_length =
JVM_GetMethodIxExceptionTableLength(context->env,
context->class,
context->method_index);
int buffer[2]; /* default value for successors */
int *successors = buffer; /* table of successors */
int successors_count;
int i;
switch (opcode) {
default:
successors_count = 1;
buffer[0] = inumber + 1;
break;
case JVM_OPC_ifeq: case JVM_OPC_ifne: case JVM_OPC_ifgt:
case JVM_OPC_ifge: case JVM_OPC_iflt: case JVM_OPC_ifle:
case JVM_OPC_ifnull: case JVM_OPC_ifnonnull:
case JVM_OPC_if_icmpeq: case JVM_OPC_if_icmpne: case JVM_OPC_if_icmpgt:
case JVM_OPC_if_icmpge: case JVM_OPC_if_icmplt: case JVM_OPC_if_icmple:
case JVM_OPC_if_acmpeq: case JVM_OPC_if_acmpne:
successors_count = 2;
buffer[0] = inumber + 1;
buffer[1] = operand;
break;
case JVM_OPC_jsr: case JVM_OPC_jsr_w:
if (this_idata->operand2.i != UNKNOWN_RET_INSTRUCTION)
idata[this_idata->operand2.i].changed = JNI_TRUE;
/* FALLTHROUGH */
case JVM_OPC_goto: case JVM_OPC_goto_w:
successors_count = 1;
buffer[0] = operand;
break;
case JVM_OPC_ireturn: case JVM_OPC_lreturn: case JVM_OPC_return:
case JVM_OPC_freturn: case JVM_OPC_dreturn: case JVM_OPC_areturn:
case JVM_OPC_athrow:
/* The testing for the returns is handled in pop_stack() */
successors_count = 0;
break;
case JVM_OPC_ret: {
/* This is slightly slow, but good enough for a seldom used instruction.
* The EXTRA_ITEM_INFO of the ITEM_ReturnAddress indicates the
* address of the first instruction of the subroutine. We can return
* to 1 after any instruction that jsr's to that instruction.
*/
if (this_idata->operand2.ip == NULL) {
fullinfo_type *registers = this_idata->register_info.registers;
int called_instruction = GET_EXTRA_INFO(registers[operand]);
int i, count, *ptr;;
for (i = context->instruction_count, count = 0; --i >= 0; ) {
if (((idata[i].opcode == JVM_OPC_jsr) ||
(idata[i].opcode == JVM_OPC_jsr_w)) &&
(idata[i].operand.i == called_instruction))
count++;
}
this_idata->operand2.ip = ptr = NEW(int, count + 1);
*ptr++ = count;
for (i = context->instruction_count, count = 0; --i >= 0; ) {
if (((idata[i].opcode == JVM_OPC_jsr) ||
(idata[i].opcode == JVM_OPC_jsr_w)) &&
(idata[i].operand.i == called_instruction))
*ptr++ = i + 1;
}
}
successors = this_idata->operand2.ip; /* use this instead */
successors_count = *successors++;
break;
}
case JVM_OPC_tableswitch:
case JVM_OPC_lookupswitch:
successors = this_idata->operand.ip; /* use this instead */
successors_count = *successors++;
break;
}
#ifdef DEBUG
if (verify_verbose) {
jio_fprintf(stdout, " [");
for (i = handler_info_length; --i >= 0; handler_info++)
if (handler_info->start <= (int)inumber && handler_info->end > (int)inumber)
jio_fprintf(stdout, "%d* ", handler_info->handler);
for (i = 0; i < successors_count; i++)
jio_fprintf(stdout, "%d ", successors[i]);
jio_fprintf(stdout, "]\n");
}
#endif
handler_info = context->handler_info;
for (i = handler_info_length; --i >= 0; handler_info++) {
if (handler_info->start <= (int)inumber && handler_info->end > (int)inumber) {
int handler = handler_info->handler;
if (opcode != JVM_OPC_invokeinit) {
merge_into_one_successor(context, inumber, handler,
&this_idata->register_info, /* old */
&handler_info->stack_info,
(flag_type) (and_flags
& this_idata->and_flags),
(flag_type) (or_flags
| this_idata->or_flags),
JNI_TRUE);
} else {
/* We need to be a little bit more careful with this
* instruction. Things could either be in the state before
* the instruction or in the state afterwards */
fullinfo_type from = context->swap_table[0];
flag_type temp_or_flags = or_flags;
if (from == MAKE_FULLINFO(ITEM_InitObject, 0, 0))
temp_or_flags |= FLAG_NO_RETURN;
merge_into_one_successor(context, inumber, handler,
&this_idata->register_info, /* old */
&handler_info->stack_info,
this_idata->and_flags,
this_idata->or_flags,
JNI_TRUE);
merge_into_one_successor(context, inumber, handler,
register_info,
&handler_info->stack_info,
and_flags, temp_or_flags, JNI_TRUE);
}
}
}
for (i = 0; i < successors_count; i++) {
int target = successors[i];
if (target >= context->instruction_count)
CCerror(context, "Falling off the end of the code");
merge_into_one_successor(context, inumber, target,
register_info, stack_info, and_flags, or_flags,
JNI_FALSE);
}
}
/* We have a new set of registers and stack values for a given instruction.
* Merge this new set into the values that are already there.
*/
static void
merge_into_one_successor(context_type *context,
unsigned int from_inumber, unsigned int to_inumber,
register_info_type *new_register_info,
stack_info_type *new_stack_info,
flag_type new_and_flags, flag_type new_or_flags,
jboolean isException)
{
instruction_data_type *idata = context->instruction_data;
register_info_type register_info_buf;
stack_info_type stack_info_buf;
#ifdef DEBUG
instruction_data_type *this_idata = &idata[to_inumber];
register_info_type old_reg_info;
stack_info_type old_stack_info;
flag_type old_and_flags = 0;
flag_type old_or_flags = 0;
#endif
#ifdef DEBUG
if (verify_verbose) {
old_reg_info = this_idata->register_info;
old_stack_info = this_idata->stack_info;
old_and_flags = this_idata->and_flags;
old_or_flags = this_idata->or_flags;
}
#endif
/* All uninitialized objects are set to "bogus" when jsr and
* ret are executed. Thus uninitialized objects can't propagate
* into or out of a subroutine.
*/
if (idata[from_inumber].opcode == JVM_OPC_ret ||
idata[from_inumber].opcode == JVM_OPC_jsr ||
idata[from_inumber].opcode == JVM_OPC_jsr_w) {
int new_register_count = new_register_info->register_count;
fullinfo_type *new_registers = new_register_info->registers;
int i;
stack_item_type *item;
for (item = new_stack_info->stack; item != NULL; item = item->next) {
if (GET_ITEM_TYPE(item->item) == ITEM_NewObject) {
/* This check only succeeds for hand-contrived code.
* Efficiency is not an issue.
*/
stack_info_buf.stack = copy_stack(context,
new_stack_info->stack);
stack_info_buf.stack_size = new_stack_info->stack_size;
new_stack_info = &stack_info_buf;
for (item = new_stack_info->stack; item != NULL;
item = item->next) {
if (GET_ITEM_TYPE(item->item) == ITEM_NewObject) {
item->item = MAKE_FULLINFO(ITEM_Bogus, 0, 0);
}
}
break;
}
}
for (i = 0; i < new_register_count; i++) {
if (GET_ITEM_TYPE(new_registers[i]) == ITEM_NewObject) {
/* This check only succeeds for hand-contrived code.
* Efficiency is not an issue.
*/
fullinfo_type *new_set = NEW(fullinfo_type,
new_register_count);
for (i = 0; i < new_register_count; i++) {
fullinfo_type t = new_registers[i];
new_set[i] = GET_ITEM_TYPE(t) != ITEM_NewObject ?
t : MAKE_FULLINFO(ITEM_Bogus, 0, 0);
}
register_info_buf.register_count = new_register_count;
register_info_buf.registers = new_set;
register_info_buf.mask_count = new_register_info->mask_count;
register_info_buf.masks = new_register_info->masks;
new_register_info = ®ister_info_buf;
break;
}
}
}
/* Returning from a subroutine is somewhat ugly. The actual thing
* that needs to get merged into the new instruction is a joining
* of info from the ret instruction with stuff in the jsr instruction
*/
if (idata[from_inumber].opcode == JVM_OPC_ret && !isException) {
int new_register_count = new_register_info->register_count;
fullinfo_type *new_registers = new_register_info->registers;
int new_mask_count = new_register_info->mask_count;
mask_type *new_masks = new_register_info->masks;
int operand = idata[from_inumber].operand.i;
int called_instruction = GET_EXTRA_INFO(new_registers[operand]);
instruction_data_type *jsr_idata = &idata[to_inumber - 1];
register_info_type *jsr_reginfo = &jsr_idata->register_info;
if (jsr_idata->operand2.i != (int)from_inumber) {
if (jsr_idata->operand2.i != UNKNOWN_RET_INSTRUCTION)
CCerror(context, "Multiple returns to single jsr");
jsr_idata->operand2.i = from_inumber;
}
if (jsr_reginfo->register_count == UNKNOWN_REGISTER_COUNT) {
/* We don't want to handle the returned-to instruction until
* we've dealt with the jsr instruction. When we get to the
* jsr instruction (if ever), we'll re-mark the ret instruction
*/
;
} else {
int register_count = jsr_reginfo->register_count;
fullinfo_type *registers = jsr_reginfo->registers;
int max_registers = MAX(register_count, new_register_count);
fullinfo_type *new_set = NEW(fullinfo_type, max_registers);
int *return_mask;
struct register_info_type new_new_register_info;
int i;
/* Make sure the place we're returning from is legal! */
for (i = new_mask_count; --i >= 0; )
if (new_masks[i].entry == called_instruction)
break;
if (i < 0)
CCerror(context, "Illegal return from subroutine");
/* pop the masks down to the indicated one. Remember the mask
* we're popping off. */
return_mask = new_masks[i].modifies;
new_mask_count = i;
for (i = 0; i < max_registers; i++) {
if (IS_BIT_SET(return_mask, i))
new_set[i] = i < new_register_count ?
new_registers[i] : MAKE_FULLINFO(ITEM_Bogus, 0, 0);
else
new_set[i] = i < register_count ?
registers[i] : MAKE_FULLINFO(ITEM_Bogus, 0, 0);
}
new_new_register_info.register_count = max_registers;
new_new_register_info.registers = new_set;
new_new_register_info.mask_count = new_mask_count;
new_new_register_info.masks = new_masks;
merge_stack(context, from_inumber, to_inumber, new_stack_info);
merge_registers(context, to_inumber - 1, to_inumber,
&new_new_register_info);
merge_flags(context, from_inumber, to_inumber, new_and_flags, new_or_flags);
}
} else {
merge_stack(context, from_inumber, to_inumber, new_stack_info);
merge_registers(context, from_inumber, to_inumber, new_register_info);
merge_flags(context, from_inumber, to_inumber,
new_and_flags, new_or_flags);
}
#ifdef DEBUG
if (verify_verbose && idata[to_inumber].changed) {
register_info_type *register_info = &this_idata->register_info;
stack_info_type *stack_info = &this_idata->stack_info;
if (memcmp(&old_reg_info, register_info, sizeof(old_reg_info)) ||
memcmp(&old_stack_info, stack_info, sizeof(old_stack_info)) ||
(old_and_flags != this_idata->and_flags) ||
(old_or_flags != this_idata->or_flags)) {
jio_fprintf(stdout, " %2d:", to_inumber);
print_stack(context, &old_stack_info);
print_registers(context, &old_reg_info);
print_flags(context, old_and_flags, old_or_flags);
jio_fprintf(stdout, " => ");
print_stack(context, &this_idata->stack_info);
print_registers(context, &this_idata->register_info);
print_flags(context, this_idata->and_flags, this_idata->or_flags);
jio_fprintf(stdout, "\n");
}
}
#endif
}
static void
merge_stack(context_type *context, unsigned int from_inumber,
unsigned int to_inumber, stack_info_type *new_stack_info)
{
instruction_data_type *idata = context->instruction_data;
instruction_data_type *this_idata = &idata[to_inumber];
int new_stack_size = new_stack_info->stack_size;
stack_item_type *new_stack = new_stack_info->stack;
int stack_size = this_idata->stack_info.stack_size;
if (stack_size == UNKNOWN_STACK_SIZE) {
/* First time at this instruction. Just copy. */
this_idata->stack_info.stack_size = new_stack_size;
this_idata->stack_info.stack = new_stack;
this_idata->changed = JNI_TRUE;
} else if (new_stack_size != stack_size) {
CCerror(context, "Inconsistent stack height %d != %d",
new_stack_size, stack_size);
} else {
stack_item_type *stack = this_idata->stack_info.stack;
stack_item_type *old, *new;
jboolean change = JNI_FALSE;
for (old = stack, new = new_stack; old != NULL;
old = old->next, new = new->next) {
if (!isAssignableTo(context, new->item, old->item)) {
change = JNI_TRUE;
break;
}
}
if (change) {
stack = copy_stack(context, stack);
for (old = stack, new = new_stack; old != NULL;
old = old->next, new = new->next) {
if (new == NULL) {
break;
}
old->item = merge_fullinfo_types(context, old->item, new->item,
JNI_FALSE);
if (GET_ITEM_TYPE(old->item) == ITEM_Bogus) {
CCerror(context, "Mismatched stack types");
}
}
if (old != NULL || new != NULL) {
CCerror(context, "Mismatched stack types");
}
this_idata->stack_info.stack = stack;
this_idata->changed = JNI_TRUE;
}
}
}
static void
merge_registers(context_type *context, unsigned int from_inumber,
unsigned int to_inumber, register_info_type *new_register_info)
{
instruction_data_type *idata = context->instruction_data;
instruction_data_type *this_idata = &idata[to_inumber];
register_info_type *this_reginfo = &this_idata->register_info;
int new_register_count = new_register_info->register_count;
fullinfo_type *new_registers = new_register_info->registers;
int new_mask_count = new_register_info->mask_count;
mask_type *new_masks = new_register_info->masks;
if (this_reginfo->register_count == UNKNOWN_REGISTER_COUNT) {
this_reginfo->register_count = new_register_count;
this_reginfo->registers = new_registers;
this_reginfo->mask_count = new_mask_count;
this_reginfo->masks = new_masks;
this_idata->changed = JNI_TRUE;
} else {
/* See if we've got new information on the register set. */
int register_count = this_reginfo->register_count;
fullinfo_type *registers = this_reginfo->registers;
int mask_count = this_reginfo->mask_count;
mask_type *masks = this_reginfo->masks;
jboolean copy = JNI_FALSE;
int i, j;
if (register_count > new_register_count) {
/* Any register larger than new_register_count is now bogus */
this_reginfo->register_count = new_register_count;
register_count = new_register_count;
this_idata->changed = JNI_TRUE;
}
for (i = 0; i < register_count; i++) {
fullinfo_type prev_value = registers[i];
if ((i < new_register_count)
? (!isAssignableTo(context, new_registers[i], prev_value))
: (prev_value != MAKE_FULLINFO(ITEM_Bogus, 0, 0))) {
copy = JNI_TRUE;
break;
}
}
if (copy) {
/* We need a copy. So do it. */
fullinfo_type *new_set = NEW(fullinfo_type, register_count);
for (j = 0; j < i; j++)
new_set[j] = registers[j];
for (j = i; j < register_count; j++) {
if (i >= new_register_count)
new_set[j] = MAKE_FULLINFO(ITEM_Bogus, 0, 0);
else
new_set[j] = merge_fullinfo_types(context,
new_registers[j],
registers[j], JNI_FALSE);
}
/* Some of the end items might now be bogus. This step isn't
* necessary, but it may save work later. */
while ( register_count > 0
&& GET_ITEM_TYPE(new_set[register_count-1]) == ITEM_Bogus)
register_count--;
this_reginfo->register_count = register_count;
this_reginfo->registers = new_set;
this_idata->changed = JNI_TRUE;
}
if (mask_count > 0) {
/* If the target instruction already has a sequence of masks, then
* we need to merge new_masks into it. We want the entries on
* the mask to be the longest common substring of the two.
* (e.g. a->b->d merged with a->c->d should give a->d)
* The bits set in the mask should be the or of the corresponding
* entries in each of the original masks.
*/
int i, j, k;
int matches = 0;
int last_match = -1;
jboolean copy_needed = JNI_FALSE;
for (i = 0; i < mask_count; i++) {
int entry = masks[i].entry;
for (j = last_match + 1; j < new_mask_count; j++) {
if (new_masks[j].entry == entry) {
/* We have a match */
int *prev = masks[i].modifies;
int *new = new_masks[j].modifies;
matches++;
/* See if new_mask has bits set for "entry" that
* weren't set for mask. If so, need to copy. */
for (k = context->bitmask_size - 1;
!copy_needed && k >= 0;
k--)
if (~prev[k] & new[k])
copy_needed = JNI_TRUE;
last_match = j;
break;
}
}
}
if ((matches < mask_count) || copy_needed) {
/* We need to make a copy for the new item, since either the
* size has decreased, or new bits are set. */
mask_type *copy = NEW(mask_type, matches);
for (i = 0; i < matches; i++) {
copy[i].modifies = NEW(int, context->bitmask_size);
}
this_reginfo->masks = copy;
this_reginfo->mask_count = matches;
this_idata->changed = JNI_TRUE;
matches = 0;
last_match = -1;
for (i = 0; i < mask_count; i++) {
int entry = masks[i].entry;
for (j = last_match + 1; j < new_mask_count; j++) {
if (new_masks[j].entry == entry) {
int *prev1 = masks[i].modifies;
int *prev2 = new_masks[j].modifies;
int *new = copy[matches].modifies;
copy[matches].entry = entry;
for (k = context->bitmask_size - 1; k >= 0; k--)
new[k] = prev1[k] | prev2[k];
matches++;
last_match = j;
break;
}
}
}
}
}
}
}
static void
merge_flags(context_type *context, unsigned int from_inumber,
unsigned int to_inumber,
flag_type new_and_flags, flag_type new_or_flags)
{
/* Set this_idata->and_flags &= new_and_flags
this_idata->or_flags |= new_or_flags
*/
instruction_data_type *idata = context->instruction_data;
instruction_data_type *this_idata = &idata[to_inumber];
flag_type this_and_flags = this_idata->and_flags;
flag_type this_or_flags = this_idata->or_flags;
flag_type merged_and = this_and_flags & new_and_flags;
flag_type merged_or = this_or_flags | new_or_flags;
if ((merged_and != this_and_flags) || (merged_or != this_or_flags)) {
this_idata->and_flags = merged_and;
this_idata->or_flags = merged_or;
this_idata->changed = JNI_TRUE;
}
}
/* Make a copy of a stack */
static stack_item_type *
copy_stack(context_type *context, stack_item_type *stack)
{
int length;
stack_item_type *ptr;
/* Find the length */
for (ptr = stack, length = 0; ptr != NULL; ptr = ptr->next, length++);
if (length > 0) {
stack_item_type *new_stack = NEW(stack_item_type, length);
stack_item_type *new_ptr;
for ( ptr = stack, new_ptr = new_stack;
ptr != NULL;
ptr = ptr->next, new_ptr++) {
new_ptr->item = ptr->item;
new_ptr->next = new_ptr + 1;
}
new_stack[length - 1].next = NULL;
return new_stack;
} else {
return NULL;
}
}
static mask_type *
copy_masks(context_type *context, mask_type *masks, int mask_count)
{
mask_type *result = NEW(mask_type, mask_count);
int bitmask_size = context->bitmask_size;
int *bitmaps = NEW(int, mask_count * bitmask_size);
int i;
for (i = 0; i < mask_count; i++) {
result[i].entry = masks[i].entry;
result[i].modifies = &bitmaps[i * bitmask_size];
memcpy(result[i].modifies, masks[i].modifies, bitmask_size * sizeof(int));
}
return result;
}
static mask_type *
add_to_masks(context_type *context, mask_type *masks, int mask_count, int d)
{
mask_type *result = NEW(mask_type, mask_count + 1);
int bitmask_size = context->bitmask_size;
int *bitmaps = NEW(int, (mask_count + 1) * bitmask_size);
int i;
for (i = 0; i < mask_count; i++) {
result[i].entry = masks[i].entry;
result[i].modifies = &bitmaps[i * bitmask_size];
memcpy(result[i].modifies, masks[i].modifies, bitmask_size * sizeof(int));
}
result[mask_count].entry = d;
result[mask_count].modifies = &bitmaps[mask_count * bitmask_size];
memset(result[mask_count].modifies, 0, bitmask_size * sizeof(int));
return result;
}
/* We create our own storage manager, since we malloc lots of little items,
* and I don't want to keep trace of when they become free. I sure wish that
* we had heaps, and I could just free the heap when done.
*/
#define CCSegSize 2000
struct CCpool { /* a segment of allocated memory in the pool */
struct CCpool *next;
int segSize; /* almost always CCSegSize */
int poolPad;
char space[CCSegSize];
};
/* Initialize the context's heap. */
static void CCinit(context_type *context)
{
struct CCpool *new = (struct CCpool *) malloc(sizeof(struct CCpool));
/* Set context->CCroot to 0 if new == 0 to tell CCdestroy to lay off */
context->CCroot = context->CCcurrent = new;
if (new == 0) {
CCout_of_memory(context);
}
new->next = NULL;
new->segSize = CCSegSize;
context->CCfree_size = CCSegSize;
context->CCfree_ptr = &new->space[0];
}
/* Reuse all the space that we have in the context's heap. */
static void CCreinit(context_type *context)
{
struct CCpool *first = context->CCroot;
context->CCcurrent = first;
context->CCfree_size = CCSegSize;
context->CCfree_ptr = &first->space[0];
}
/* Destroy the context's heap. */
static void CCdestroy(context_type *context)
{
struct CCpool *this = context->CCroot;
while (this) {
struct CCpool *next = this->next;
free(this);
this = next;
}
/* These two aren't necessary. But can't hurt either */
context->CCroot = context->CCcurrent = NULL;
context->CCfree_ptr = 0;
}
/* Allocate an object of the given size from the context's heap. */
static void *
CCalloc(context_type *context, int size, jboolean zero)
{
register char *p;
/* Round CC to the size of a pointer */
size = (size + (sizeof(void *) - 1)) & ~(sizeof(void *) - 1);
if (context->CCfree_size < size) {
struct CCpool *current = context->CCcurrent;
struct CCpool *new;
if (size > CCSegSize) { /* we need to allocate a special block */
new = (struct CCpool *)malloc(sizeof(struct CCpool) +
(size - CCSegSize));
if (new == 0) {
CCout_of_memory(context);
}
new->next = current->next;
new->segSize = size;
current->next = new;
} else {
new = current->next;
if (new == NULL) {
new = (struct CCpool *) malloc(sizeof(struct CCpool));
if (new == 0) {
CCout_of_memory(context);
}
current->next = new;
new->next = NULL;
new->segSize = CCSegSize;
}
}
context->CCcurrent = new;
context->CCfree_ptr = &new->space[0];
context->CCfree_size = new->segSize;
}
p = context->CCfree_ptr;
context->CCfree_ptr += size;
context->CCfree_size -= size;
if (zero)
memset(p, 0, size);
return p;
}
/* Get the class associated with a particular field or method or class in the
* constant pool. If is_field is true, we've got a field or method. If
* false, we've got a class.
*/
static fullinfo_type
cp_index_to_class_fullinfo(context_type *context, int cp_index, int kind)
{
JNIEnv *env = context->env;
fullinfo_type result;
const char *classname;
switch (kind) {
case JVM_CONSTANT_Class:
classname = JVM_GetCPClassNameUTF(env,
context->class,
cp_index);
break;
case JVM_CONSTANT_Methodref:
classname = JVM_GetCPMethodClassNameUTF(env,
context->class,
cp_index);
break;
case JVM_CONSTANT_Fieldref:
classname = JVM_GetCPFieldClassNameUTF(env,
context->class,
cp_index);
break;
default:
classname = NULL;
CCerror(context, "Internal error #5");
}
check_and_push(context, classname, VM_STRING_UTF);
if (classname[0] == JVM_SIGNATURE_ARRAY) {
/* This make recursively call us, in case of a class array */
signature_to_fieldtype(context, &classname, &result);
} else {
result = make_class_info_from_name(context, classname);
}
pop_and_free(context);
return result;
}
static int
print_CCerror_info(context_type *context)
{
JNIEnv *env = context->env;
jclass cb = context->class;
const char *classname = JVM_GetClassNameUTF(env, cb);
const char *name = 0;
const char *signature = 0;
int n = 0;
if (context->method_index != -1) {
name = JVM_GetMethodIxNameUTF(env, cb, context->method_index);
signature =
JVM_GetMethodIxSignatureUTF(env, cb, context->method_index);
n += jio_snprintf(context->message, context->message_buf_len,
"(class: %s, method: %s signature: %s) ",
(classname ? classname : ""),
(name ? name : ""),
(signature ? signature : ""));
} else if (context->field_index != -1 ) {
name = JVM_GetMethodIxNameUTF(env, cb, context->field_index);
n += jio_snprintf(context->message, context->message_buf_len,
"(class: %s, field: %s) ",
(classname ? classname : 0),
(name ? name : 0));
} else {
n += jio_snprintf(context->message, context->message_buf_len,
"(class: %s) ", classname ? classname : "");
}
JVM_ReleaseUTF(classname);
JVM_ReleaseUTF(name);
JVM_ReleaseUTF(signature);
return n;
}
static void
CCerror (context_type *context, char *format, ...)
{
int n = print_CCerror_info(context);
va_list args;
if (n >= 0 && n < context->message_buf_len) {
va_start(args, format);
jio_vsnprintf(context->message + n, context->message_buf_len - n,
format, args);
va_end(args);
}
context->err_code = CC_VerifyError;
longjmp(context->jump_buffer, 1);
}
static void
CCout_of_memory(context_type *context)
{
int n = print_CCerror_info(context);
context->err_code = CC_OutOfMemory;
longjmp(context->jump_buffer, 1);
}
static void
CFerror(context_type *context, char *format, ...)
{
int n = print_CCerror_info(context);
va_list args;
if (n >= 0 && n < context->message_buf_len) {
va_start(args, format);
jio_vsnprintf(context->message + n, context->message_buf_len - n,
format, args);
va_end(args);
}
context->err_code = CC_ClassFormatError;
longjmp(context->jump_buffer, 1);
}
/*
* Need to scan the entire signature to find the result type because
* types in the arg list and the result type could contain embedded ')'s.
*/
static const char* get_result_signature(const char* signature) {
const char *p;
for (p = signature; *p != JVM_SIGNATURE_ENDFUNC; p++) {
switch (*p) {
case JVM_SIGNATURE_BOOLEAN:
case JVM_SIGNATURE_BYTE:
case JVM_SIGNATURE_CHAR:
case JVM_SIGNATURE_SHORT:
case JVM_SIGNATURE_INT:
case JVM_SIGNATURE_FLOAT:
case JVM_SIGNATURE_DOUBLE:
case JVM_SIGNATURE_LONG:
case JVM_SIGNATURE_FUNC: /* ignore initial (, if given */
break;
case JVM_SIGNATURE_CLASS:
while (*p != JVM_SIGNATURE_ENDCLASS) p++;
break;
case JVM_SIGNATURE_ARRAY:
while (*p == JVM_SIGNATURE_ARRAY) p++;
/* If an array of classes, skip over class name, too. */
if (*p == JVM_SIGNATURE_CLASS) {
while (*p != JVM_SIGNATURE_ENDCLASS) p++;
}
break;
default:
/* Indicate an error. */
return NULL;
}
}
return p++; /* skip over ')'. */
}
static char
signature_to_fieldtype(context_type *context,
const char **signature_p, fullinfo_type *full_info_p)
{
const char *p = *signature_p;
fullinfo_type full_info = MAKE_FULLINFO(ITEM_Bogus, 0, 0);
char result;
int array_depth = 0;
for (;;) {
switch(*p++) {
default:
result = 0;
break;
case JVM_SIGNATURE_BOOLEAN:
full_info = (array_depth > 0)
? MAKE_FULLINFO(ITEM_Boolean, 0, 0)
: MAKE_FULLINFO(ITEM_Integer, 0, 0);
result = 'I';
break;
case JVM_SIGNATURE_BYTE:
full_info = (array_depth > 0)
? MAKE_FULLINFO(ITEM_Byte, 0, 0)
: MAKE_FULLINFO(ITEM_Integer, 0, 0);
result = 'I';
break;
case JVM_SIGNATURE_CHAR:
full_info = (array_depth > 0)
? MAKE_FULLINFO(ITEM_Char, 0, 0)
: MAKE_FULLINFO(ITEM_Integer, 0, 0);
result = 'I';
break;
case JVM_SIGNATURE_SHORT:
full_info = (array_depth > 0)
? MAKE_FULLINFO(ITEM_Short, 0, 0)
: MAKE_FULLINFO(ITEM_Integer, 0, 0);
result = 'I';
break;
case JVM_SIGNATURE_INT:
full_info = MAKE_FULLINFO(ITEM_Integer, 0, 0);
result = 'I';
break;
case JVM_SIGNATURE_FLOAT:
full_info = MAKE_FULLINFO(ITEM_Float, 0, 0);
result = 'F';
break;
case JVM_SIGNATURE_DOUBLE:
full_info = MAKE_FULLINFO(ITEM_Double, 0, 0);
result = 'D';
break;
case JVM_SIGNATURE_LONG:
full_info = MAKE_FULLINFO(ITEM_Long, 0, 0);
result = 'L';
break;
case JVM_SIGNATURE_ARRAY:
array_depth++;
continue; /* only time we ever do the loop > 1 */
case JVM_SIGNATURE_CLASS: {
char buffer_space[256];
char *buffer = buffer_space;
char *finish = strchr(p, JVM_SIGNATURE_ENDCLASS);
int length;
if (finish == NULL) {
/* Signature must have ';' after the class name.
* If it does not, return 0 and ITEM_Bogus in full_info. */
result = 0;
break;
}
assert(finish >= p);
length = (int)(finish - p);
if (length + 1 > (int)sizeof(buffer_space)) {
buffer = malloc(length + 1);
check_and_push(context, buffer, VM_MALLOC_BLK);
}
memcpy(buffer, p, length);
buffer[length] = '\0';
full_info = make_class_info_from_name(context, buffer);
result = 'A';
p = finish + 1;
if (buffer != buffer_space)
pop_and_free(context);
break;
}
} /* end of switch */
break;
}
*signature_p = p;
if (array_depth == 0 || result == 0) {
/* either not an array, or result is bogus */
*full_info_p = full_info;
return result;
} else {
if (array_depth > MAX_ARRAY_DIMENSIONS)
CCerror(context, "Array with too many dimensions");
*full_info_p = MAKE_FULLINFO(GET_ITEM_TYPE(full_info),
array_depth,
GET_EXTRA_INFO(full_info));
return 'A';
}
}
/* Given an array type, create the type that has one less level of
* indirection.
*/
static fullinfo_type
decrement_indirection(fullinfo_type array_info)
{
if (array_info == NULL_FULLINFO) {
return NULL_FULLINFO;
} else {
int type = GET_ITEM_TYPE(array_info);
int indirection = GET_INDIRECTION(array_info) - 1;
int extra_info = GET_EXTRA_INFO(array_info);
if ( (indirection == 0)
&& ((type == ITEM_Short || type == ITEM_Byte || type == ITEM_Boolean || type == ITEM_Char)))
type = ITEM_Integer;
return MAKE_FULLINFO(type, indirection, extra_info);
}
}
/* See if we can assign an object of the "from" type to an object
* of the "to" type.
*/
static jboolean isAssignableTo(context_type *context,
fullinfo_type from, fullinfo_type to)
{
return (merge_fullinfo_types(context, from, to, JNI_TRUE) == to);
}
/* Given two fullinfo_type's, find their lowest common denominator. If
* the assignable_p argument is non-null, we're really just calling to find
* out if "<target> := <value>" is a legitimate assignment.
*
* We treat all interfaces as if they were of type java/lang/Object, since the
* runtime will do the full checking.
*/
static fullinfo_type
merge_fullinfo_types(context_type *context,
fullinfo_type value, fullinfo_type target,
jboolean for_assignment)
{
JNIEnv *env = context->env;
if (value == target) {
/* If they're identical, clearly just return what we've got */
return value;
}
/* Both must be either arrays or objects to go further */
if (GET_INDIRECTION(value) == 0 && GET_ITEM_TYPE(value) != ITEM_Object)
return MAKE_FULLINFO(ITEM_Bogus, 0, 0);
if (GET_INDIRECTION(target) == 0 && GET_ITEM_TYPE(target) != ITEM_Object)
return MAKE_FULLINFO(ITEM_Bogus, 0, 0);
/* If either is NULL, return the other. */
if (value == NULL_FULLINFO)
return target;
else if (target == NULL_FULLINFO)
return value;
/* If either is java/lang/Object, that's the result. */
if (target == context->object_info)
return target;
else if (value == context->object_info) {
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