/*

 * Copyright (c) 2002, 2018, 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.

 *

 * 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.

 *

 */

#include <objc/objc-runtime.h>

#import <Foundation/Foundation.h>

#import <JavaNativeFoundation/JavaNativeFoundation.h>

#import <JavaRuntimeSupport/JavaRuntimeSupport.h>

#include <jni.h>

#import <mach/mach.h>

#import <mach/mach_types.h>

#import <sys/sysctl.h>

#import <stdio.h>

#import <string.h>

#import <stdarg.h>

#import <stdlib.h>

#import <strings.h>

#import <dlfcn.h>

#import <limits.h>

#import <errno.h>

#import <sys/types.h>

#import <sys/ptrace.h>

#include "libproc_impl.h"

#define UNSUPPORTED_ARCH "Unsupported architecture!"

#if defined(x86_64) && !defined(amd64)

#define amd64 1

#endif

#if amd64

#include "sun_jvm_hotspot_debugger_amd64_AMD64ThreadContext.h"

#else

#error UNSUPPORTED_ARCH

#endif

static jfieldID symbolicatorID = 0; // set in _init0

static jfieldID taskID = 0; // set in _init0

static jfieldID p_ps_prochandle_ID = 0;

static jfieldID loadObjectList_ID = 0;

static jmethodID listAdd_ID = 0;

static jmethodID createClosestSymbol_ID = 0;

static jmethodID createLoadObject_ID = 0;

static jmethodID getJavaThreadsInfo_ID = 0;

// indicator if thread id (lwpid_t) was set

static bool _threads_filled = false;

// mach_exc_server defined in the generated mach_excServer.c

extern boolean_t mach_exc_server(mach_msg_header_t *input_msg_hdr,

                                 mach_msg_header_t *output_msg_hdr);

kern_return_t catch_mach_exception_raise(

  mach_port_t exception_port, mach_port_t thread,

  mach_port_t task, exception_type_t exception,

  mach_exception_data_t code,

  mach_msg_type_number_t code_cnt);

kern_return_t catch_mach_exception_raise_state(

  mach_port_t exception_port, exception_type_t exception,

  const mach_exception_data_t code, mach_msg_type_number_t code_cnt,

  int *flavor, const thread_state_t old_state,

  mach_msg_type_number_t old_state_cnt, thread_state_t new_state,

  mach_msg_type_number_t *new_state_cnt);

kern_return_t catch_mach_exception_raise_state_identity(

  mach_port_t exception_port, mach_port_t thread, mach_port_t task,

  exception_type_t exception, mach_exception_data_t code,

  mach_msg_type_number_t code_cnt, int *flavor, thread_state_t old_state,

  mach_msg_type_number_t old_state_cnt, thread_state_t new_state,

  mach_msg_type_number_t *new_state_cnt);

static struct exception_saved_state {

  exception_mask_t       saved_masks[EXC_TYPES_COUNT];

  mach_port_t            saved_ports[EXC_TYPES_COUNT];

  exception_behavior_t   saved_behaviors[EXC_TYPES_COUNT];

  thread_state_flavor_t  saved_flavors[EXC_TYPES_COUNT];

  mach_msg_type_number_t saved_exception_types_count;

} exception_saved_state;

static mach_port_t tgt_exception_port;

// Mirrors __Reply__mach_exception_raise_t generated in mach_excServer.c

static struct rep_msg {

  mach_msg_header_t header;

  NDR_record_t ndr;

  kern_return_t ret_code;

} rep_msg;

// Mirrors __Request__mach_exception_raise_t generated in mach_excServer.c

// with a large trailing pad to avoid MACH_MSG_RCV_TOO_LARGE

static struct exc_msg {

  mach_msg_header_t header;

  // start of the kernel processed data

  mach_msg_body_t msgh_body;

  mach_msg_port_descriptor_t thread;

  mach_msg_port_descriptor_t task;

  // end of the kernel processed data

  NDR_record_t ndr;

  exception_type_t exception;

  mach_msg_type_number_t code_cnt;

  mach_exception_data_t code; // an array of int64_t

  char pad[512];

} exc_msg;

static void putSymbolicator(JNIEnv *env, jobject this_obj, id symbolicator) {

  (*env)->SetLongField(env, this_obj, symbolicatorID, (jlong)(intptr_t)symbolicator);

}

static id getSymbolicator(JNIEnv *env, jobject this_obj) {

  jlong ptr = (*env)->GetLongField(env, this_obj, symbolicatorID);

  return (id)(intptr_t)ptr;

}

static void putTask(JNIEnv *env, jobject this_obj, task_t task) {

  (*env)->SetLongField(env, this_obj, taskID, (jlong)task);

}

static task_t getTask(JNIEnv *env, jobject this_obj) {

  jlong ptr = (*env)->GetLongField(env, this_obj, taskID);

  return (task_t)ptr;

}

#define CHECK_EXCEPTION_(value) if ((*env)->ExceptionOccurred(env)) { return value; }

#define CHECK_EXCEPTION if ((*env)->ExceptionOccurred(env)) { return;}

#define THROW_NEW_DEBUGGER_EXCEPTION_(str, value) { throw_new_debugger_exception(env, str); return value; }

#define THROW_NEW_DEBUGGER_EXCEPTION(str) { throw_new_debugger_exception(env, str); return;}

#define CHECK_EXCEPTION_CLEAR if ((*env)->ExceptionOccurred(env)) { (*env)->ExceptionClear(env); }

#define CHECK_EXCEPTION_CLEAR_VOID if ((*env)->ExceptionOccurred(env)) { (*env)->ExceptionClear(env); return; }

#define CHECK_EXCEPTION_CLEAR_(value) if ((*env)->ExceptionOccurred(env)) { (*env)->ExceptionClear(env); return value; }

static void throw_new_debugger_exception(JNIEnv* env, const char* errMsg) {

  jclass exceptionClass = (*env)->FindClass(env, "sun/jvm/hotspot/debugger/DebuggerException");

  CHECK_EXCEPTION;

  (*env)->ThrowNew(env, exceptionClass, errMsg);

}

static struct ps_prochandle* get_proc_handle(JNIEnv* env, jobject this_obj) {

  jlong ptr = (*env)->GetLongField(env, this_obj, p_ps_prochandle_ID);

  return (struct ps_prochandle*)(intptr_t)ptr;

}

#if defined(__i386__)

    #define hsdb_thread_state_t     x86_thread_state32_t

    #define hsdb_float_state_t      x86_float_state32_t

    #define HSDB_THREAD_STATE       x86_THREAD_STATE32

    #define HSDB_FLOAT_STATE        x86_FLOAT_STATE32

    #define HSDB_THREAD_STATE_COUNT x86_THREAD_STATE32_COUNT

    #define HSDB_FLOAT_STATE_COUNT  x86_FLOAT_STATE32_COUNT

#elif defined(__x86_64__)

    #define hsdb_thread_state_t     x86_thread_state64_t

    #define hsdb_float_state_t      x86_float_state64_t

    #define HSDB_THREAD_STATE       x86_THREAD_STATE64

    #define HSDB_FLOAT_STATE        x86_FLOAT_STATE64

    #define HSDB_THREAD_STATE_COUNT x86_THREAD_STATE64_COUNT

    #define HSDB_FLOAT_STATE_COUNT  x86_FLOAT_STATE64_COUNT

#else

    #error UNSUPPORTED_ARCH

#endif

/*

 * Class:     sun_jvm_hotspot_debugger_bsd_BsdDebuggerLocal

 * Method:    init0

 * Signature: ()V

 */

JNIEXPORT void JNICALL

Java_sun_jvm_hotspot_debugger_bsd_BsdDebuggerLocal_init0(JNIEnv *env, jclass cls) {

  symbolicatorID = (*env)->GetFieldID(env, cls, "symbolicator", "J");

  CHECK_EXCEPTION;

  taskID = (*env)->GetFieldID(env, cls, "task", "J");

  CHECK_EXCEPTION;

  // for core file

  p_ps_prochandle_ID = (*env)->GetFieldID(env, cls, "p_ps_prochandle", "J");

  CHECK_EXCEPTION;

  loadObjectList_ID = (*env)->GetFieldID(env, cls, "loadObjectList", "Ljava/util/List;");

  CHECK_EXCEPTION;

  // methods we use

  createClosestSymbol_ID = (*env)->GetMethodID(env, cls, "createClosestSymbol",

                    "(Ljava/lang/String;J)Lsun/jvm/hotspot/debugger/cdbg/ClosestSymbol;");

  CHECK_EXCEPTION;

  createLoadObject_ID = (*env)->GetMethodID(env, cls, "createLoadObject",

                    "(Ljava/lang/String;JJ)Lsun/jvm/hotspot/debugger/cdbg/LoadObject;");

  CHECK_EXCEPTION;

  // java.util.List method we call

  jclass listClass = (*env)->FindClass(env, "java/util/List");

  CHECK_EXCEPTION;

  listAdd_ID = (*env)->GetMethodID(env, listClass, "add", "(Ljava/lang/Object;)Z");

  CHECK_EXCEPTION;

  getJavaThreadsInfo_ID = (*env)->GetMethodID(env, cls, "getJavaThreadsInfo",

                                                     "()[J");

  CHECK_EXCEPTION;

  init_libproc(getenv("LIBSAPROC_DEBUG") != NULL);

}

JNIEXPORT jint JNICALL Java_sun_jvm_hotspot_debugger_bsd_BsdDebuggerLocal_getAddressSize

  (JNIEnv *env, jclass cls)

{

#ifdef _LP64

  return 8;

#else

  #error UNSUPPORTED_ARCH

#endif

}

/** called by Java_sun_jvm_hotspot_debugger_bsd_BsdDebuggerLocal_lookupByName0 */

jlong lookupByNameIncore(

  JNIEnv *env, struct ps_prochandle *ph, jobject this_obj, jstring objectName, jstring symbolName)

{

  const char *objectName_cstr, *symbolName_cstr;

  jlong addr;

  jboolean isCopy;

  objectName_cstr = NULL;

  if (objectName != NULL) {

    objectName_cstr = (*env)->GetStringUTFChars(env, objectName, &isCopy);

    CHECK_EXCEPTION_(0);

  }

  symbolName_cstr = (*env)->GetStringUTFChars(env, symbolName, &isCopy);

  CHECK_EXCEPTION_(0);

  print_debug("look for %s \n", symbolName_cstr);

  addr = (jlong) lookup_symbol(ph, objectName_cstr, symbolName_cstr);

  if (objectName_cstr != NULL) {

    (*env)->ReleaseStringUTFChars(env, objectName, objectName_cstr);

  }

  (*env)->ReleaseStringUTFChars(env, symbolName, symbolName_cstr);

  return addr;

}

/*

 * Class:     sun_jvm_hotspot_debugger_bsd_BsdDebuggerLocal

 * Method:    lookupByName0

 * Signature: (Ljava/lang/String;Ljava/lang/String;)J

 */

JNIEXPORT jlong JNICALL

Java_sun_jvm_hotspot_debugger_bsd_BsdDebuggerLocal_lookupByName0(

  JNIEnv *env, jobject this_obj,

  jstring objectName, jstring symbolName)

{

  struct ps_prochandle* ph = get_proc_handle(env, this_obj);

  if (ph != NULL && ph->core != NULL) {

    return lookupByNameIncore(env, ph, this_obj, objectName, symbolName);

  }

  jlong address = 0;

JNF_COCOA_ENTER(env);

  NSString *symbolNameString = JNFJavaToNSString(env, symbolName);

  print_debug("lookupInProcess called for %s\n", [symbolNameString UTF8String]);

  id symbolicator = getSymbolicator(env, this_obj);

  if (symbolicator != nil) {

    uint64_t (*dynamicCall)(id, SEL, NSString *) = (uint64_t (*)(id, SEL, NSString *))&objc_msgSend;

    address = (jlong) dynamicCall(symbolicator, @selector(addressForSymbol:), symbolNameString);

  }

  print_debug("address of symbol %s = %llx\n", [symbolNameString UTF8String], address);

JNF_COCOA_EXIT(env);

  return address;

}

/*

 * Class:     sun_jvm_hotspot_debugger_bsd_BsdDebuggerLocal

 * Method:    lookupByAddress0

 * Signature: (J)Lsun/jvm/hotspot/debugger/cdbg/ClosestSymbol;

 */

JNIEXPORT jobject JNICALL Java_sun_jvm_hotspot_debugger_bsd_BsdDebuggerLocal_lookupByAddress0

  (JNIEnv *env, jobject this_obj, jlong addr) {

  uintptr_t offset;

  const char* sym = NULL;

  jstring sym_string;

  struct ps_prochandle* ph = get_proc_handle(env, this_obj);

  if (ph != NULL && ph->core != NULL) {

    sym = symbol_for_pc(ph, (uintptr_t) addr, &offset);

    if (sym == NULL) return 0;

    sym_string = (*env)->NewStringUTF(env, sym);

    CHECK_EXCEPTION_(0);

    return (*env)->CallObjectMethod(env, this_obj, createClosestSymbol_ID,

                                                sym_string, (jlong)offset);

  }

  return 0;

}

/** called from Java_sun_jvm_hotspot_debugger_bsd_BsdDebuggerLocal_readBytesFromProcess0 */

jbyteArray readBytesFromCore(

  JNIEnv *env, struct ps_prochandle *ph, jobject this_obj, jlong addr, jlong numBytes)

{

  jboolean isCopy;

  jbyteArray array;

  jbyte *bufPtr;

  ps_err_e err;

  array = (*env)->NewByteArray(env, numBytes);

  CHECK_EXCEPTION_(0);

  bufPtr = (*env)->GetByteArrayElements(env, array, &isCopy);

  CHECK_EXCEPTION_(0);

  err = ps_pread(ph, (psaddr_t) (uintptr_t)addr, bufPtr, numBytes);

  (*env)->ReleaseByteArrayElements(env, array, bufPtr, 0);

  return (err == PS_OK)? array : 0;

}

/*

 * Class:     sun_jvm_hotspot_debugger_bsd_BsdDebuggerLocal

 * Method:    readBytesFromProcess0

 * Signature: (JJ)Lsun/jvm/hotspot/debugger/ReadResult;

 */

JNIEXPORT jbyteArray JNICALL

Java_sun_jvm_hotspot_debugger_bsd_BsdDebuggerLocal_readBytesFromProcess0(

  JNIEnv *env, jobject this_obj,

  jlong addr, jlong numBytes)

{

  print_debug("readBytesFromProcess called. addr = %llx numBytes = %lld\n", addr, numBytes);

  // must allocate storage instead of using former parameter buf

  jbyteArray array;

  struct ps_prochandle* ph = get_proc_handle(env, this_obj);

  if (ph != NULL && ph->core != NULL) {

    return readBytesFromCore(env, ph, this_obj, addr, numBytes);

  }

  array = (*env)->NewByteArray(env, numBytes);

  CHECK_EXCEPTION_(0);

  unsigned long alignedAddress;

  unsigned long alignedLength = 0;

  kern_return_t result;

  vm_offset_t *pages;

  int *mapped;

  long pageCount;

  uint byteCount;

  int i;

  unsigned long remaining;

  alignedAddress = trunc_page(addr);

  if (addr != alignedAddress) {

    alignedLength += addr - alignedAddress;

  }

  alignedLength = round_page(numBytes);

  pageCount = alignedLength/vm_page_size;

  // Allocate storage for pages and flags.

  pages = malloc(pageCount * sizeof(vm_offset_t));

  mapped = calloc(pageCount, sizeof(int));

  task_t gTask = getTask(env, this_obj);

  // Try to read each of the pages.

  for (i = 0; i < pageCount; i++) {

    result = vm_read(gTask, alignedAddress + i*vm_page_size, vm_page_size,

		     &pages[i], &byteCount);

    mapped[i] = (result == KERN_SUCCESS);

    // assume all failures are unmapped pages

  }

  print_debug("%ld pages\n", pageCount);

  remaining = numBytes;

  for (i = 0; i < pageCount; i++) {

    unsigned long len = vm_page_size;

    unsigned long start = 0;

    if (i == 0) {

      start = addr - alignedAddress;

      len = vm_page_size - start;

    }

    if (i == (pageCount - 1)) {

      len = remaining;

    }

    if (mapped[i]) {

      print_debug("page %d mapped (len %ld start %ld)\n", i, len, start);

      (*env)->SetByteArrayRegion(env, array, 0, len, ((jbyte *) pages[i] + start));

      vm_deallocate(mach_task_self(), pages[i], vm_page_size);

    }

    remaining -= len;

  }

  free (pages);

  free (mapped);

  return array;

}

/** Only used for core file reading, set thread_id for threads which is got after core file parsed.

  * Thread context is available in Mach-O core file but thread id is not. We can get thread id

  * from Threads which store all java threads information when they are created. Here we can identify

  * them as java threads by checking if a thread's rsp or rbp within a java thread's stack.

  * Note Macosx uses unique_thread_id which is different from other platforms though printed ids

  * are still pthread id. Function BsdDebuggerLocal.getJavaThreadsInfo returns an array of long

  * integers to host all java threads' id, stack_start, stack_end as:

  * [uid0, stack_start0, stack_end0, uid1, stack_start1, stack_end1, ...]

  *

  * The work cannot be done at init0 since Threads is not available yet(VM not initialized yet).

  * This function should be called only once if succeeded

  */

bool fill_java_threads(JNIEnv* env, jobject this_obj, struct ps_prochandle* ph) {

  int n = 0, i = 0, j;

  struct reg regs;

  jlongArray thrinfos = (*env)->CallObjectMethod(env, this_obj, getJavaThreadsInfo_ID);

  CHECK_EXCEPTION_(false);

  int len = (int)(*env)->GetArrayLength(env, thrinfos);

  uint64_t* cinfos = (uint64_t *)(*env)->GetLongArrayElements(env, thrinfos, NULL);

  CHECK_EXCEPTION_(false);

  n = get_num_threads(ph);

  print_debug("fill_java_threads called, num_of_thread = %d\n", n);

  for (i = 0; i < n; i++) {

    if (!get_nth_lwp_regs(ph, i, &regs)) {

      print_debug("Could not get regs of thread %d, already set!\n", i);

      return false;

    }

    for (j = 0; j < len; j += 3) {

      lwpid_t  uid = cinfos[j];

      uint64_t beg = cinfos[j + 1];

      uint64_t end = cinfos[j + 2];

      if ((regs.r_rsp < end && regs.r_rsp >= beg) ||

          (regs.r_rbp < end && regs.r_rbp >= beg)) {

        set_lwp_id(ph, i, uid);

        break;

      }

    }

  }

  (*env)->ReleaseLongArrayElements(env, thrinfos, (jlong*)cinfos, 0);

  CHECK_EXCEPTION_(false);

  return true;

}

/* For core file only, called from

 * Java_sun_jvm_hotspot_debugger_bsd_BsdDebuggerLocal_getThreadIntegerRegisterSet0

 */

jlongArray getThreadIntegerRegisterSetFromCore(JNIEnv *env, jobject this_obj, long lwp_id, struct ps_prochandle* ph) {

  if (!_threads_filled)  {

    if (!fill_java_threads(env, this_obj, ph)) {

      throw_new_debugger_exception(env, "Failed to fill in threads");

      return 0;

    } else {

      _threads_filled = true;

    }

  }

  struct reg gregs;

  jboolean isCopy;

  jlongArray array;

  jlong *regs;

  if (get_lwp_regs(ph, lwp_id, &gregs) != true) {

    THROW_NEW_DEBUGGER_EXCEPTION_("get_thread_regs failed for a lwp", 0);

  }

#undef NPRGREG

#undef REG_INDEX

#if amd64

#define NPRGREG sun_jvm_hotspot_debugger_amd64_AMD64ThreadContext_NPRGREG

#define REG_INDEX(reg) sun_jvm_hotspot_debugger_amd64_AMD64ThreadContext_##reg

  array = (*env)->NewLongArray(env, NPRGREG);

  CHECK_EXCEPTION_(0);

  regs = (*env)->GetLongArrayElements(env, array, &isCopy);

  regs[REG_INDEX(R15)] = gregs.r_r15;

  regs[REG_INDEX(R14)] = gregs.r_r14;

  regs[REG_INDEX(R13)] = gregs.r_r13;

  regs[REG_INDEX(R12)] = gregs.r_r12;

  regs[REG_INDEX(RBP)] = gregs.r_rbp;

  regs[REG_INDEX(RBX)] = gregs.r_rbx;

  regs[REG_INDEX(R11)] = gregs.r_r11;