1 /* Target operations for the Valgrind remote server for GDB. 2 Copyright (C) 2002, 2003, 2004, 2005, 2012 3 Free Software Foundation, Inc. 4 Philippe Waroquiers. 5 6 Contributed by MontaVista Software. 7 8 This file is part of GDB. 9 It has been modified to integrate it in valgrind 10 11 This program is free software; you can redistribute it and/or modify 12 it under the terms of the GNU General Public License as published by 13 the Free Software Foundation; either version 2 of the License, or 14 (at your option) any later version. 15 16 This program is distributed in the hope that it will be useful, 17 but WITHOUT ANY WARRANTY; without even the implied warranty of 18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 GNU General Public License for more details. 20 21 You should have received a copy of the GNU General Public License 22 along with this program; if not, write to the Free Software 23 Foundation, Inc., 51 Franklin Street, Fifth Floor, 24 Boston, MA 02110-1301, USA. */ 25 26 #ifndef TARGET_H 27 #define TARGET_H 28 29 #include "pub_core_basics.h" // Addr 30 #include "server.h" // CORE_ADDR 31 32 /* This file defines the architecture independent Valgrind gdbserver 33 high level operations such as read memory, get/set registers, ... 34 35 These high level operations are called by the gdbserver 36 protocol implementation (e.g. typically server.c). 37 38 For some of these high level operations, target.c will call 39 low level operations dependent on the architecture. 40 41 For example, getting or setting the registers will work on a 42 register cache. The exact details of the registers (how much, 43 their size, etc) is not defined by target.c or the register cache. 44 45 Such architecture dependent information is defined by 46 valgrind_low.h/valgrind-low-xxxxx.c providing 'low level operations' 47 specific to the xxxxx architecture (for example, 48 valgrind-low-x86.c, valgrind-low-armc.c). */ 49 50 /* -------------------------------------------------------------------------- */ 51 /* ------------------------ Initialisation ---------------------------------- */ 52 /* -------------------------------------------------------------------------- */ 53 54 /* Initialize the Valgrind high target. This will in turn 55 initialise the low (architecture specific) target. */ 56 extern void valgrind_initialize_target(void); 57 58 /* initialize or re-initialize the register set of the low target. 59 if shadow_mode, then (re-)define the normal and valgrind shadow registers 60 else (re-)define only the normal registers. */ 61 extern void initialize_shadow_low (Bool shadow_mode); 62 63 /* Returns the name of the xml target description file. 64 returns NULL if no xml target description available. 65 if shadow_mode, then returns the xml target description 66 with the shadow registers 67 else returns the xml target description only for 68 the normal registers. */ 69 extern const char* valgrind_target_xml (Bool shadow_mode); 70 71 72 /* -------------------------------------------------------------------------- */ 73 /* --------------------------- Execution control ---------------------------- */ 74 /* -------------------------------------------------------------------------- */ 75 76 /* This structure describes how to resume the execution. 77 Currently, there is no way to resume only a specific thread. */ 78 struct thread_resume 79 { 80 /* If non-zero, we want to single-step. */ 81 int step; 82 83 /* If non-zero, send this signal when we resume. */ 84 int sig; 85 }; 86 87 /* Prepare to Resume (i.e. restart) the guest. 88 The resume info indicates how the resume will be done. 89 In case GDB has changed the program counter, valgrind_resume 90 will also ensure that the execution will be resumed at this 91 new program counter. 92 The Resume is really only executed once the gdbserver 93 returns (giving back the control to Valgrind). */ 94 extern void valgrind_resume (struct thread_resume *resume_info); 95 96 /* When Valgrind gets the control, it will execute the guest 97 process till there is a reason to call the gdbserver 98 again (e.g. because a breakpoint is encountered or the 99 tool reports an error). 100 In such case, the executionof guest code stops, and the 101 control is given to gdbserver. Gdbserver will send a resume 102 reply packet to GDB. 103 104 valgrind_wait gets from Valgrind data structures the 105 information needed produce the resume reply for GDB: 106 a.o. OURSTATUS will be filled in with a response code to send to GDB. 107 108 Returns the signal which caused the process to stop, in the 109 remote protocol numbering (e.g. TARGET_SIGNAL_STOP), or the 110 exit code as an integer if *OURSTATUS is 'W'. */ 111 extern unsigned char valgrind_wait (char *outstatus); 112 113 /* When execution is stopped and gdbserver has control, more 114 info about the stop reason can be retrieved using the following 115 functions. */ 116 117 /* gets the addr at which a (possible) break must be ignored once. 118 If there is no such break to be ignored once, 0 is returned. 119 This is needed for the following case: 120 The user sets a break at address AAA. 121 The break is encountered. Then the user does stepi 122 (i.e. step one instruction). 123 In such a case, the already encountered break must be ignored 124 to ensure the stepi will advance by one instruction: a "break" 125 is implemented in valgrind by some helper code just after the 126 instruction mark at which the break is set. This helper code 127 verifies if either there is a break at the current PC 128 or if we are in stepping mode. If we are in stepping mode, 129 the already encountered break must be ignored once to advance 130 to the next instruction. 131 ??? need to check if this is *really* needed. */ 132 extern Addr valgrind_get_ignore_break_once(void); 133 134 /* When addr > 0, ensures the next resume reply packet informs 135 gdb about the encountered watchpoint. 136 valgrind_stopped_by_watchpoint() will return 1 till reset. 137 Use addr 0x0 to reset. */ 138 extern void VG_(set_watchpoint_stop_address) (Addr addr); 139 140 /* Returns 1 if target was stopped due to a watchpoint hit, 0 otherwise. */ 141 extern int valgrind_stopped_by_watchpoint (void); 142 143 /* Returns the address associated with the watchpoint that hit, if any; 144 returns 0 otherwise. */ 145 extern CORE_ADDR valgrind_stopped_data_address (void); 146 147 148 /* Inform GDB (if needed) that client is before (or after) syscall sysno. 149 sysno -1 is used to clear the fact that a syscall has been encountered. */ 150 extern void gdbserver_syscall_encountered (Bool before, Int sysno); 151 152 /* >= 0 if valgrind stopped due to syscall, -1 if not stopped due to syscall. */ 153 extern Int valgrind_stopped_by_syscall (void); 154 155 /* if valgrind_stopped_by_syscall() >= 0, tells if stopped before or after 156 syscall. */ 157 extern Bool valgrind_stopped_before_syscall (void); 158 159 /* True if gdbserver is single stepping the valgrind process */ 160 extern Bool valgrind_single_stepping (void); 161 162 /* Set Valgrind in single stepping mode or not according to Bool. */ 163 extern void valgrind_set_single_stepping (Bool); 164 165 /* -------------------------------------------------------------------------- */ 166 /* ----------------- Examining/modifying data while stopped ----------------- */ 167 /* -------------------------------------------------------------------------- */ 168 169 /* Return 1 iff the thread with ID tid is alive. */ 170 extern int valgrind_thread_alive (unsigned long tid); 171 172 /* Allows to controls the thread (current_inferior) used for following 173 valgrind_(fetch|store)_registers calls. 174 If USE_GENERAL, 175 current_inferior is set to general_thread 176 else 177 current_inferior is set to step_thread or else cont_thread. 178 If the above gives no valid thread, then current_inferior is 179 set to the first valid thread. */ 180 extern void set_desired_inferior (int use_general); 181 182 /* Fetch registers from the current_inferior thread. 183 If REGNO is -1, fetch all registers; otherwise, fetch at least REGNO. */ 184 extern void valgrind_fetch_registers (int regno); 185 186 /* Store registers to the current_inferior thread. 187 If REGNO is -1, store all registers; otherwise, store at least REGNO. */ 188 extern void valgrind_store_registers (int regno); 189 190 191 192 /* Read memory from the inferior process. 193 Read LEN bytes at MEMADDR into a buffer at MYADDR. 194 Returns 0 on success and errno on failure. */ 195 extern int valgrind_read_memory (CORE_ADDR memaddr, 196 unsigned char *myaddr, int len); 197 198 /* Write memory to the inferior process. 199 Write LEN bytes from the buffer at MYADDR to MEMADDR. 200 Returns 0 on success and errno on failure. */ 201 extern int valgrind_write_memory (CORE_ADDR memaddr, 202 const unsigned char *myaddr, int len); 203 204 205 /* Insert and remove a hardware watchpoint. 206 Returns 0 on success, -1 on failure and 1 on unsupported. 207 The type is coded as follows: 208 2 = write watchpoint 209 3 = read watchpoint 210 4 = access watchpoint 211 */ 212 extern int valgrind_insert_watchpoint (char type, CORE_ADDR addr, int len); 213 extern int valgrind_remove_watchpoint (char type, CORE_ADDR addr, int len); 214 215 /* Get the address of a thread local variable. 216 'tst' is the thread for which thread local address is searched for. 217 'offset' is the offset of the variable in the tls data of the load 218 module identified by 'lm'. 219 'lm' is the link_map address of the loaded module : it is the address 220 of the data structure used by the dynamic linker to maintain various 221 information about a loaded object. 222 223 Returns True if the address of the variable could be found. 224 *tls_addr is then set to this address. 225 Returns False if tls support is not available for this arch, or 226 if an error occurred. *tls_addr is set to NULL. */ 227 extern Bool valgrind_get_tls_addr (ThreadState *tst, 228 CORE_ADDR offset, 229 CORE_ADDR lm, 230 CORE_ADDR *tls_addr); 231 232 233 /* -------------------------------------------------------------------------- */ 234 /* ----------- Utils functions for low level arch specific files ------------ */ 235 /* -------------------------------------------------------------------------- */ 236 237 238 /* returns a pointer to the architecture state corresponding to 239 the provided register set: 0 => normal guest registers, 240 1 => shadow1 241 2 => shadow2 242 */ 243 extern VexGuestArchState* get_arch (int set, ThreadState* tst); 244 245 /* like memcpy but first check if content of destination and source 246 differs. If no difference, no copy is done, *mod set to False. 247 If different; copy is done, *mod set to True. */ 248 extern void* VG_(dmemcpy) ( void *d, const void *s, SizeT sz, Bool *mod ); 249 250 typedef 251 enum { 252 valgrind_to_gdbserver, 253 gdbserver_to_valgrind} transfer_direction; 254 255 // According to dir, calls VG_(dmemcpy) 256 // to copy data from/to valgrind to/from gdbserver. 257 // If the transferred data differs from what is currently stored, 258 // sets *mod to True otherwise set *mod to False. 259 extern void VG_(transfer) (void *valgrind, 260 void *gdbserver, 261 transfer_direction dir, 262 SizeT sz, 263 Bool *mod); 264 265 266 // True means gdbserver can access (internal) Valgrind memory. 267 // Otherwise, only the client memory can be accessed. 268 extern Bool hostvisibility; 269 270 #endif /* TARGET_H */ 271