1 2 /*--------------------------------------------------------------------*/ 3 /*--- Handle remote gdb protocol. pub_core_gdbserver.h ---*/ 4 /*--------------------------------------------------------------------*/ 5 6 /* 7 This file is part of Valgrind, a dynamic binary instrumentation 8 framework. 9 10 Copyright (C) 2011-2013 Philippe Waroquiers 11 12 This program is free software; you can redistribute it and/or 13 modify it under the terms of the GNU General Public License as 14 published by the Free Software Foundation; either version 2 of the 15 License, or (at your option) any later version. 16 17 This program is distributed in the hope that it will be useful, but 18 WITHOUT ANY WARRANTY; without even the implied warranty of 19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 20 General Public License for more details. 21 22 You should have received a copy of the GNU General Public License 23 along with this program; if not, write to the Free Software 24 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 25 02111-1307, USA. 26 27 The GNU General Public License is contained in the file COPYING. 28 */ 29 30 #ifndef __PUB_CORE_GDBSERVER_H 31 #define __PUB_CORE_GDBSERVER_H 32 33 #include "pub_tool_gdbserver.h" 34 #include "pub_core_options.h" 35 #include "pub_core_threadstate.h" // VgSchedReturnCode 36 37 /* Return the default path prefix for the named pipes (FIFOs) used by vgdb/gdb 38 to communicate with valgrind */ 39 HChar* VG_(vgdb_prefix_default)(void); 40 41 // After a fork or after an exec, call the below to (possibly) terminate 42 // the previous gdbserver and then activate a new gdbserver 43 // before any guest code execution, to e.g. allow the user to set 44 // breakpoints before execution. 45 // If VG_(clo_vgdb) == No, the below has no effect. 46 void VG_(gdbserver_prerun_action) (ThreadId tid); 47 48 // True if the initialisation of gdbserver was done, 49 // i.e. VG_(gdbserver_prerun_action) was called. 50 Bool VG_(gdbserver_init_done) (void); 51 52 // True if gdbserver should stop execution for the specified stop at reason 53 Bool VG_(gdbserver_stop_at) (VgdbStopAt stopat); 54 55 // True if there is some activity from vgdb 56 // If it returns True, then extern void VG_(gdbserver) can be called 57 // to handle this incoming vgdb request. 58 extern Bool VG_(gdbserver_activity) (ThreadId tid); 59 60 // If connected to GDB, VG_(gdbserver_exit) reports to GDB that the process 61 // is about to exit. 62 // gdbserver is then stopped (using VG_(gdbserver) (0)) 63 void VG_(gdbserver_exit) (ThreadId tid, VgSchedReturnCode tids_schedretcode); 64 65 /* On systems that defines PR_SET_PTRACER, verify if ptrace_scope is 66 is permissive enough for vgdb or --db-attach=yes. 67 Otherwise, call set_ptracer. 68 This is especially aimed at Ubuntu >= 10.10 which has added 69 the ptrace_scope context. */ 70 void VG_(set_ptracer)(void); 71 72 /* Called by low level to insert or remove a break or watch point. 73 Break or watch point implementation is done using help from the tool. 74 break point support implies some (small) specific instrumentation 75 taken in charge for all tools by m_translate.c. 76 77 Write/read/access watchpoint can only be provided by tools which are 78 tracking addressability and/or accessibility of memory 79 (so typically memcheck can provide it). Note that memcheck addressability 80 bits do not differentiate between read and write accessibility. 81 However, when accessing unaddressable byte, memcheck can differentiate 82 reads from write, thereby providing read/write or access watchpoints. 83 84 Note that gdbserver assumes that software breakpoint is supported 85 (as this will be done by re-instrumenting the code). 86 Note that len is ignored for sofware breakpoints. hardware_breakpoint 87 are not supported. 88 89 Returns True if the point has properly been inserted or removed 90 Returns False otherwise. */ 91 Bool VG_(gdbserver_point) (PointKind kind, Bool insert, 92 Addr addr, int len); 93 94 /* True if there is a breakpoint at addr. */ 95 Bool VG_(has_gdbserver_breakpoint) (Addr addr); 96 97 /* Entry point invoked by vgdb when it uses ptrace to cause a gdbserver 98 invocation. A magic value is passed by vgdb in check as a verification 99 that the call has been properly pushed by vgdb. */ 100 extern void VG_(invoke_gdbserver) ( int check ); 101 102 // To be called by core (m_signals.c) before delivering a signal. 103 // Returns True unless gdb user asks to not pass the signal to the client. 104 // Note that if the below returns True, the signal might 105 // still be ignored if this is the action desired by the 106 // guest program. 107 extern Bool VG_(gdbserver_report_signal) (Int signo, ThreadId tid); 108 109 /* Entry point invoked by scheduler.c to execute the request 110 VALGRIND_CLIENT_MONITOR_COMMAND. 111 Returns True if command was not recognised. */ 112 extern Bool VG_(client_monitor_command) (HChar* cmd); 113 114 /* software_breakpoint, single step and jump support ------------------------*/ 115 /* VG_(instrument_for_gdbserver_if_needed) allows to do "standard and easy" 116 instrumentation for gdbserver. 117 VG_(instrument_for_gdbserver_if_needed) does the following: 118 * checks if gdbserver instrumentation is needed for vge. 119 * if no gdbserver instrumentation needed, 120 returns sb_in 121 * otherwise 122 It will instrument sb_in to allow gdbserver to properly 123 handle breakpoints and single_stepping in sb_in. 124 All the target jumps of sb_in will also be invalidated 125 if these are not yet instrumented for gdbserver. 126 This allows to have single_step working, using a lazily 127 translation of the blocks which are being single stepped 128 in. 129 130 The typical usage of this function is to call it on the block 131 instrumented by the tool instrument function i.e. : 132 return VG_(instrument_for_gdbserver_if_needed) (sb_out, 133 layout, 134 vge, 135 gWordTy, 136 hWordTy); 137 where sb_out is the block instrumented by the tool. 138 139 If the block contains a call to a dirty helper that indirectly 140 calls gdbserver, then this dirty helper can (indirectly) change 141 the IP. This implies to jump to this IP after the call to 142 gdbserver. */ 143 extern IRSB* VG_(instrument_for_gdbserver_if_needed) 144 (IRSB* sb_in, /* block to be instrumented */ 145 VexGuestLayout* layout, 146 VexGuestExtents* vge, 147 IRType gWordTy, IRType hWordTy); 148 149 /* reason for which gdbserver connection must be finished */ 150 typedef 151 enum { 152 orderly_finish, 153 reset_after_error, 154 reset_after_fork} FinishReason; 155 156 /* output various gdbserver statistics and status. */ 157 extern void VG_(gdbserver_status_output)(void); 158 159 /* Shared structure between vgdb and the process running 160 under valgrind. 161 We define two variants: a 32 bit and a 64 bit. 162 The valgrind process will use the appropriate size, 163 according to the architecture. 164 vgdb will use what the valgrind process is using. */ 165 /* The below takes care that sizes will be 32 or 64 bits, 166 whatever the architecture. A.o., vgdb.c cannot use directly 167 the types from pub_core_threadstate.h as we want vgdb.c to 168 be independent of the arch it is debugging in case of bi-arch 169 Valgrind (e.g. x86 and amd64). So, the valgrind process must 170 give all the needed info/offset to vgdb in the below structure. */ 171 172 typedef 173 struct { 174 // nr of bytes vgdb has written to valgrind 175 volatile int written_by_vgdb; 176 // nr of bytes seen by valgrind 177 volatile int seen_by_valgrind; 178 179 // address at which gdbserver can be invoked 180 Addr32 invoke_gdbserver; 181 182 // address of VG_(threads) and various sizes 183 // and offset needed by vgdb. 184 Addr32 threads; 185 int sizeof_ThreadState; 186 int offset_status; 187 int offset_lwpid; 188 189 // PID of the vgdb that last connected to the Valgrind gdbserver. 190 // It will be set by vgdb after connecting. 191 int vgdb_pid; 192 } VgdbShared32; 193 194 /* Same as VgdbShared32 but for 64 bits arch. */ 195 typedef 196 struct { 197 volatile int written_by_vgdb; 198 volatile int seen_by_valgrind; 199 200 Addr64 invoke_gdbserver; 201 202 Addr64 threads; 203 int sizeof_ThreadState; 204 int offset_status; 205 int offset_lwpid; 206 207 int vgdb_pid; 208 } VgdbShared64; 209 210 // The below typedef makes the life of valgrind easier. 211 // vgdb must however work explicitely with the specific 32 or 64 bits version. 212 213 #if VEX_HOST_WORDSIZE == 8 214 typedef VgdbShared64 VgdbShared; 215 #elif VEX_HOST_WORDSIZE == 4 216 typedef VgdbShared32 VgdbShared; 217 #else 218 # error "unexpected wordsize" 219 #endif 220 221 222 #endif // __PUB_CORE_GDBSERVER_H 223 /*--------------------------------------------------------------------*/ 224 /*--- end ---*/ 225 /*--------------------------------------------------------------------*/ 226
