1 2 /*--------------------------------------------------------------------*/ 3 /*--- Handle remote gdb protocol. pub_tool_gdbserver.h ---*/ 4 /*--------------------------------------------------------------------*/ 5 6 /* 7 This file is part of Valgrind, a dynamic binary instrumentation 8 framework. 9 10 Copyright (C) 2011-2017 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_TOOL_GDBSERVER_H 31 #define __PUB_TOOL_GDBSERVER_H 32 33 #include "pub_tool_basics.h" // VG_ macro 34 35 //-------------------------------------------------------------------- 36 // PURPOSE: This module provides the support to have a gdb 37 // connecting to a valgrind process using remote gdb protocol. It provides 38 // * A function to allow a tool (or the valgrind core) to 39 // wait for a gdb to connect and then handle gdb commands. 40 // Typically, this can be used to let the user debug the process 41 // when valgrind reports an error. 42 // * A function allowing to instrument the code to support gdb breakpoints. 43 // * A function allowing the tool to support watchpoints. 44 // * A utility function to help implementing the processing of the 45 // gdb_monitor_command strings. 46 47 48 // Function to be used by tool or coregrind to allow a gdb to connect 49 // to this process. 50 // Calling VG_(gdbserver) with tid > 0 means to let a debugger attach 51 // to the valgrind process. gdbserver will report to gdb that the 52 // process stopped in thread tid. 53 // Calling VG_(gdbserver) with tid == 0 indicates to close 54 // the connection with GDB (if still open) and stop gdbserver. 55 //-------------------------------------------------------------------- 56 extern void VG_(gdbserver) ( ThreadId tid ); 57 58 /* VG_(dyn_vgdb_error) gets its initial value from 59 VG_(clo_vgdb_error). It can be changed after initial command 60 processing in order to enable/disable the call to VG_(gdbserver) in 61 m_errormgr.c. The main reasons to change the below is either 62 because the user updates it via a monitor command or to 63 (temporarily) avoid calling gdbserver for error reporting during 64 monitor command handling. 65 */ 66 extern Int VG_(dyn_vgdb_error); 67 68 /* defines the various kinds of breakpoints that gdbserver 69 might ask to insert/remove. Note that the below matches 70 the gdbserver protocol definition. The level of support 71 of the various breakpoint kinds depends on the tool. 72 73 For the moment, it is unclear how a tool would implement 74 hardware_breakpoint in valgrind :). 75 76 software_breakpoint implies some (small) specific 77 instrumentation to be done for gdbserver. This instrumentation 78 is implemented for all tools in m_translate.c. 79 80 write/read/access watchpoints can only be done by tools 81 which are maintaining some notion of address accessibility 82 as part of their instrumentation. watchpoints can then 83 be done by marking the watched address(es) as not accessible. 84 But instead of giving back an error (or whatever the tool 85 wants to do with unaccessible mechanism), the tool must then 86 just call gdbserver. See memcheck for an example of reusing 87 accessibility for watchpoint support. 88 */ 89 typedef 90 enum { 91 software_breakpoint, 92 hardware_breakpoint, 93 write_watchpoint, 94 read_watchpoint, 95 access_watchpoint } PointKind; 96 extern const HChar* VG_(ppPointKind) (PointKind kind); 97 98 99 /* watchpoint support --------------------------------------*/ 100 /* True if one or more bytes in [addr, addr+len[ are being watched by 101 gdbserver for write or read or access. 102 In addition, VG_(is_watched) will invoke gdbserver if 103 the access provided by the tool matches the watchpoint kind. 104 For this, the tool must pass the kind of access it has detected: 105 write_watchpoint indicates the tool has detected a write 106 read_watchpoint indicates the tool has detected a read 107 access_watchpoint indicates the tool has detected an access but does 108 not know if this is a read or a write 109 */ 110 extern Bool VG_(is_watched)(PointKind kind, Addr addr, Int szB); 111 112 extern void VG_(needs_watchpoint) ( 113 // indicates the given Addr/len is being watched (insert) 114 // or not watched anymore (! insert). 115 // gdbserver will maintain the list of watched addresses. 116 // The tool can use VG_(is_watched) to verify if an 117 // access to an Addr is in one of the watched intervals. 118 // Must return True if the watchpoint has been properly inserted or 119 // removed. False if not supported. 120 // Note that an address can only be watched for a single kind. 121 // The tool must be ready to be called successively with 122 // multiple kinds for the same addr and len and with 123 // different kinds. The last kind must replace the previous values. 124 // Behaviour with multiple watches having overlapping addr+len 125 // is undefined. 126 Bool (*watchpoint) (PointKind kind, Bool insert, Addr addr, SizeT len) 127 ); 128 129 130 // can be used during the processing of the VG_USERREQ__GDB_MONITOR_COMMAND 131 // tool client request to output information to gdb or vgdb. 132 // The output of VG_(gdb_printf) is not subject to 'output control' 133 // by the user: e.g. the monitor command 'v.set log_output' has no effect. 134 // The output of VG_(gdb_printf) is given to gdb/vgdb. The only case 135 // in which this output is not given to gdb/vgdb is when the connection 136 // with gdb/vgdb has been lost : in such a case, output is written 137 // to the valgrind log output. 138 // To produce some output which is subject to user output control via 139 // monitor command v.set gdb_output or mixed output, use VG_(printf) 140 // or VG_(umsg) or similar. 141 // Typically, VG_(gdb_printf) has to be used when there is no point 142 // having this output in the output log of Valgrind. Examples 143 // is the monitor help output, or if vgdb is used to implement 144 // 'tool control scripts' such as callgrind_control. 145 extern UInt VG_(gdb_printf) ( const HChar *format, ... ) PRINTF_CHECK(1, 2); 146 147 /* Utility functions to (e.g.) parse gdb monitor commands. 148 149 keywords is a set of keywords separated by a space 150 keyword_id will search for the keyword starting with the string input_word 151 and return its position. 152 It returns -1 if no keyword matches. 153 It returns -2 if two or more keywords are starting with input_word 154 and none of these matches exactly input_word 155 Example with keywords = "hello world here is hell" : 156 input_word result 157 ---------- ------ 158 paradise => -1 159 i => 3 160 hell => 4 161 hel => -2 162 ishtar => -1 163 164 report indicates when to output an error msg with VG_(gdb_printf). 165 kwd_report_none : no error is reported. 166 kwd_report_all : the error msg will show all possible keywords 167 kwd_report_duplicated_matches : the error msg will show only the 168 ambiguous matches. 169 */ 170 typedef 171 enum { 172 kwd_report_none, 173 kwd_report_all, 174 kwd_report_duplicated_matches } kwd_report_error; 175 extern Int VG_(keyword_id) (const HChar* keywords, const HChar* input_word, 176 kwd_report_error report); 177 178 /* Extract an address and (optionally) a size from the string 179 currently being parsed by strtok_r (see pub_tool_libcbase.h). 180 If no size in the string, keeps the current value of szB. 181 If parsing is ok, 182 returns True. 183 If parsing is not ok; 184 set *address and *szB to 0, 185 reports problem to the user using VG_(gdb_printf) 186 returns False. */ 187 extern Bool VG_(strtok_get_address_and_size) (Addr* address, 188 SizeT* szB, 189 HChar **ssaveptr); 190 191 /* Print various statistics about Valgrind core, 192 and optionally tool and memory statistics. */ 193 extern void VG_(print_all_stats) (Bool memory_stats, Bool tool_stats); 194 195 #endif // __PUB_TOOL_GDBSERVER_H 196 197 /*--------------------------------------------------------------------*/ 198 /*--- end ---*/ 199 /*--------------------------------------------------------------------*/ 200