1 /*
   2  * Copyright (c) 2003, 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef _LIBPROC_H_
  26 #define _LIBPROC_H_
  27 
  28 #include <jni.h>
  29 #include <unistd.h>
  30 #include <stdint.h>
  31 #include "proc_service.h"
  32 
  33 #ifdef ALT_SASRCDIR
  34 #include "libproc_md.h"
  35 #endif
  36 
  37 #include <sys/ptrace.h>
  38 
  39 /************************************************************************************
  40 
  41 0. This is very minimal subset of Solaris libproc just enough for current application.
  42 Please note that the bulk of the functionality is from proc_service interface. This
  43 adds Pgrab__ and some missing stuff. We hide the difference b/w live process and core
  44 file by this interface.
  45 
  46 1. pthread_id unique in both NPTL & LinuxThreads. We store this in
  47 OSThread::_pthread_id in JVM code.
  48 
  49 2. All threads see the same pid when they call getpid() under NPTL.
  50 Threads receive different pid under LinuxThreads. We used to save the result of
  51 ::getpid() call in OSThread::_thread_id. This way uniqueness of OSThread::_thread_id
  52 was lost under NPTL. Now, we store the result of ::gettid() call in
  53 OSThread::_thread_id. Because gettid returns actual pid of thread (lwp id), this is
  54 unique again. We therefore use OSThread::_thread_id as unique identifier.
  55 
  56 3. There is a unique LWP id under both thread libraries. libthread_db  maps pthread_id
  57 to its underlying lwp_id under both the thread libraries. thread_info.lwp_id stores
  58 lwp_id of the thread. The lwp id is nothing but the actual pid of clone'd processes. But
  59 unfortunately libthread_db does not work very well for core dumps. So, we get pthread_id
  60 only for processes. For core dumps, we don't use libthread_db at all (like gdb).
  61 
  62 4. ptrace operates on this LWP id under both the thread libraries. When we say 'pid' for
  63 ptrace call, we refer to lwp_id of the thread.
  64 
  65 5. for core file, we parse ELF files and read data from them. For processes we  use
  66 combination of ptrace and /proc calls.
  67 
  68 *************************************************************************************/
  69 
  70 
  71 #if defined(sparc) || defined(sparcv9) || defined(ppc64) || defined(ppc64le)
  72 #include <asm/ptrace.h>
  73 #define user_regs_struct  pt_regs
  74 #endif
  75 #if defined(aarch64) || defined(arm64)
  76 #include <asm/ptrace.h>
  77 #define user_regs_struct user_pt_regs
  78 #elif defined(arm)
  79 #include <asm/ptrace.h>
  80 #define user_regs_struct  pt_regs
  81 #endif
  82 #if defined(s390x)
  83 #include <asm/ptrace.h>
  84 #endif
  85 
  86 // This C bool type must be int for compatibility with Linux calls and
  87 // it would be a mistake to equivalence it to C++ bool on many platforms
  88 
  89 typedef int bool;
  90 #define true  1
  91 #define false 0
  92 
  93 struct ps_prochandle;
  94 
  95 // attach to a process
  96 struct ps_prochandle* Pgrab(pid_t pid, char* err_buf, size_t err_buf_len);
  97 
  98 // attach to a core dump
  99 struct ps_prochandle* Pgrab_core(const char* execfile, const char* corefile);
 100 
 101 // release a process or core
 102 void Prelease(struct ps_prochandle* ph);
 103 
 104 // functions not directly available in Solaris libproc
 105 
 106 // initialize libproc (call this only once per app)
 107 // pass true to make library verbose
 108 bool init_libproc(bool verbose);
 109 
 110 // get number of threads
 111 int get_num_threads(struct ps_prochandle* ph);
 112 
 113 // get lwp_id of n'th thread
 114 lwpid_t get_lwp_id(struct ps_prochandle* ph, int index);
 115 
 116 // get regs for a given lwp
 117 bool get_lwp_regs(struct ps_prochandle* ph, lwpid_t lid, struct user_regs_struct* regs);
 118 
 119 // get number of shared objects
 120 int get_num_libs(struct ps_prochandle* ph);
 121 
 122 // get name of n'th lib
 123 const char* get_lib_name(struct ps_prochandle* ph, int index);
 124 
 125 // get base of lib
 126 uintptr_t get_lib_base(struct ps_prochandle* ph, int index);
 127 
 128 // returns true if given library is found in lib list
 129 bool find_lib(struct ps_prochandle* ph, const char *lib_name);
 130 
 131 // symbol lookup
 132 uintptr_t lookup_symbol(struct ps_prochandle* ph,  const char* object_name,
 133                        const char* sym_name);
 134 
 135 // address->nearest symbol lookup. return NULL for no symbol
 136 const char* symbol_for_pc(struct ps_prochandle* ph, uintptr_t addr, uintptr_t* poffset);
 137 
 138 struct ps_prochandle* get_proc_handle(JNIEnv* env, jobject this_obj);
 139 
 140 void throw_new_debugger_exception(JNIEnv* env, const char* errMsg);
 141 
 142 #endif //__LIBPROC_H_