1 /* Select target systems and architectures at runtime for GDB.
2 Copyright 1990, 1992, 1993 Free Software Foundation, Inc.
3 Contributed by Cygnus Support.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
35 target_info PARAMS ((char *, int));
38 cleanup_target PARAMS ((struct target_ops *));
41 maybe_kill_then_create_inferior PARAMS ((char *, char *, char **));
44 maybe_kill_then_attach PARAMS ((char *, int));
47 kill_or_be_killed PARAMS ((int));
50 default_terminal_info PARAMS ((char *, int));
53 nosymbol PARAMS ((char *, CORE_ADDR *));
56 tcomplain PARAMS ((void));
59 nomemory PARAMS ((CORE_ADDR, char *, int, int));
62 return_zero PARAMS ((void));
65 ignore PARAMS ((void));
68 target_command PARAMS ((char *, int));
70 static struct target_ops *
71 find_default_run_target PARAMS ((char *));
73 /* Pointer to array of target architecture structures; the size of the
74 array; the current index into the array; the allocated size of the
76 struct target_ops **target_structs;
77 unsigned target_struct_size;
78 unsigned target_struct_index;
79 unsigned target_struct_allocsize;
80 #define DEFAULT_ALLOCSIZE 10
82 /* The initial current target, so that there is always a semi-valid
85 struct target_ops dummy_target = {"None", "None", "",
86 0, 0, /* open, close */
87 find_default_attach, 0, /* attach, detach */
88 0, 0, /* resume, wait */
89 0, 0, 0, /* registers */
92 0, 0, 0, 0, 0, /* terminal */
93 0, 0, /* kill, load */
94 0, /* lookup_symbol */
95 find_default_create_inferior, /* create_inferior */
96 0, /* mourn_inferior */
98 0, /* notice_signals */
99 dummy_stratum, 0, /* stratum, next */
100 0, 0, 0, 0, 0, /* all mem, mem, stack, regs, exec */
101 0, 0, /* section pointers */
105 /* The target structure we are currently using to talk to a process
106 or file or whatever "inferior" we have. */
108 struct target_ops *current_target;
110 /* The stack of target structures that have been pushed. */
112 struct target_ops **current_target_stack;
114 /* Command list for target. */
116 static struct cmd_list_element *targetlist = NULL;
118 /* The user just typed 'target' without the name of a target. */
122 target_command (arg, from_tty)
126 fputs_filtered ("Argument required (target name). Try `help target'\n",
130 /* Add a possible target architecture to the list. */
134 struct target_ops *t;
136 if (t->to_magic != OPS_MAGIC)
138 fprintf(stderr, "Magic number of %s target struct wrong\n",
145 target_struct_allocsize = DEFAULT_ALLOCSIZE;
146 target_structs = (struct target_ops **) xmalloc
147 (target_struct_allocsize * sizeof (*target_structs));
149 if (target_struct_size >= target_struct_allocsize)
151 target_struct_allocsize *= 2;
152 target_structs = (struct target_ops **)
153 xrealloc ((char *) target_structs,
154 target_struct_allocsize * sizeof (*target_structs));
156 target_structs[target_struct_size++] = t;
159 if (targetlist == NULL)
160 add_prefix_cmd ("target", class_run, target_command,
161 "Connect to a target machine or process.\n\
162 The first argument is the type or protocol of the target machine.\n\
163 Remaining arguments are interpreted by the target protocol. For more\n\
164 information on the arguments for a particular protocol, type\n\
165 `help target ' followed by the protocol name.",
166 &targetlist, "target ", 0, &cmdlist);
167 add_cmd (t->to_shortname, no_class, t->to_open, t->to_doc, &targetlist);
179 nomemory (memaddr, myaddr, len, write)
185 errno = EIO; /* Can't read/write this location */
186 return 0; /* No bytes handled */
192 error ("You can't do that when your target is `%s'",
193 current_target->to_shortname);
199 error ("You can't do that without a process to debug");
204 nosymbol (name, addrp)
208 return 1; /* Symbol does not exist in target env */
213 default_terminal_info (args, from_tty)
217 printf("No saved terminal information.\n");
221 /* With strata, this function is no longer needed. FIXME. */
222 /* This is the default target_create_inferior function. It looks up
223 the stack for some target that cares to create inferiors, then
224 calls it -- or complains if not found. */
227 upstack_create_inferior (exec, args, env)
232 struct target_ops *t;
234 for (t = current_target;
238 if (t->to_create_inferior != upstack_create_inferior)
240 t->to_create_inferior (exec, args, env);
249 /* This is the default target_create_inferior and target_attach function.
250 If the current target is executing, it asks whether to kill it off.
251 If this function returns without calling error(), it has killed off
252 the target, and the operation should be attempted. */
255 kill_or_be_killed (from_tty)
258 if (target_has_execution)
260 printf ("You are already running a program:\n");
261 target_files_info ();
262 if (query ("Kill it? ")) {
264 if (target_has_execution)
265 error ("Killing the program did not help.");
268 error ("Program not killed.");
275 maybe_kill_then_attach (args, from_tty)
279 kill_or_be_killed (from_tty);
280 target_attach (args, from_tty);
284 maybe_kill_then_create_inferior (exec, args, env)
289 kill_or_be_killed (0);
290 target_create_inferior (exec, args, env);
293 /* Clean up a target struct so it no longer has any zero pointers in it.
294 We default entries, at least to stubs that print error messages. */
298 struct target_ops *t;
301 /* Check magic number. If wrong, it probably means someone changed
302 the struct definition, but not all the places that initialize one. */
303 if (t->to_magic != OPS_MAGIC)
305 fprintf(stderr, "Magic number of %s target struct wrong\n",
310 #define de_fault(field, value) \
311 if (!t->field) t->field = value
313 /* FIELD DEFAULT VALUE */
315 de_fault (to_open, (void (*)())tcomplain);
316 de_fault (to_close, (void (*)())ignore);
317 de_fault (to_attach, maybe_kill_then_attach);
318 de_fault (to_detach, (void (*)())ignore);
319 de_fault (to_resume, (void (*)())noprocess);
320 de_fault (to_wait, (int (*)())noprocess);
321 de_fault (to_fetch_registers, (void (*)())ignore);
322 de_fault (to_store_registers, (void (*)())noprocess);
323 de_fault (to_prepare_to_store, (void (*)())noprocess);
324 de_fault (to_xfer_memory, (int (*)())nomemory);
325 de_fault (to_files_info, (void (*)())ignore);
326 de_fault (to_insert_breakpoint, memory_insert_breakpoint);
327 de_fault (to_remove_breakpoint, memory_remove_breakpoint);
328 de_fault (to_terminal_init, ignore);
329 de_fault (to_terminal_inferior, ignore);
330 de_fault (to_terminal_ours_for_output,ignore);
331 de_fault (to_terminal_ours, ignore);
332 de_fault (to_terminal_info, default_terminal_info);
333 de_fault (to_kill, (void (*)())noprocess);
334 de_fault (to_load, (void (*)())tcomplain);
335 de_fault (to_lookup_symbol, nosymbol);
336 de_fault (to_create_inferior, maybe_kill_then_create_inferior);
337 de_fault (to_mourn_inferior, (void (*)())noprocess);
338 de_fault (to_can_run, return_zero);
339 de_fault (to_notice_signals, (void (*)())ignore);
340 de_fault (to_next, 0);
341 de_fault (to_has_all_memory, 0);
342 de_fault (to_has_memory, 0);
343 de_fault (to_has_stack, 0);
344 de_fault (to_has_registers, 0);
345 de_fault (to_has_execution, 0);
350 /* Push a new target type into the stack of the existing target accessors,
351 possibly superseding some of the existing accessors.
353 Result is zero if the pushed target ended up on top of the stack,
354 nonzero if at least one target is on top of it.
356 Rather than allow an empty stack, we always have the dummy target at
357 the bottom stratum, so we can call the function vectors without
362 struct target_ops *t;
364 struct target_ops *st, *prev;
366 for (prev = 0, st = current_target;
368 prev = st, st = st->to_next) {
369 if ((int)(t->to_stratum) >= (int)(st->to_stratum))
373 while (t->to_stratum == st->to_stratum) {
374 /* There's already something on this stratum. Close it off. */
377 prev->to_next = st->to_next; /* Unchain old target_ops */
379 current_target = st->to_next; /* Unchain first on list */
383 /* We have removed all targets in our stratum, now add ourself. */
390 cleanup_target (current_target);
394 /* Remove a target_ops vector from the stack, wherever it may be.
395 Return how many times it was removed (0 or 1 unless bug). */
399 struct target_ops *t;
401 struct target_ops *u, *v;
404 for (u = current_target, v = 0;
406 v = u, u = u->to_next)
410 pop_target(); /* unchain top copy */
412 (t->to_close)(0); /* Let it clean up */
413 v->to_next = t->to_next; /* unchain middle copy */
423 (current_target->to_close)(0); /* Let it clean up */
424 current_target = current_target->to_next;
426 /* This will dump core if ever called--push_target expects current_target
427 to be non-NULL. But I don't think it's needed; I don't see how the
428 dummy_target could ever be removed from the stack. */
429 if (!current_target) /* At bottom, push dummy. */
430 push_target (&dummy_target);
435 #define MIN(A, B) (((A) <= (B)) ? (A) : (B))
437 /* target_read_string -- read a null terminated string from MEMADDR in target.
438 The read may also be terminated early by getting an error from target_xfer_
440 LEN is the size of the buffer pointed to by MYADDR. Note that a terminating
441 null will only be written if there is sufficient room. The return value is
442 is the number of bytes (including the null) actually transferred.
446 target_read_string (memaddr, myaddr, len)
451 int tlen, origlen, offset, i;
458 tlen = MIN (len, 4 - (memaddr & 3));
459 offset = memaddr & 3;
461 if (target_xfer_memory (memaddr & ~3, buf, 4, 0))
462 return origlen - len;
464 for (i = 0; i < tlen; i++)
466 *myaddr++ = buf[i + offset];
467 if (buf[i + offset] == '\000')
468 return (origlen - len) + i + 1;
477 /* Read LEN bytes of target memory at address MEMADDR, placing the results in
478 GDB's memory at MYADDR. Returns either 0 for success or an errno value
481 If an error occurs, no guarantee is made about the contents of the data at
482 MYADDR. In particular, the caller should not depend upon partial reads
483 filling the buffer with good data. There is no way for the caller to know
484 how much good data might have been transfered anyway. Callers that can
485 deal with partial reads should call target_read_memory_partial. */
488 target_read_memory (memaddr, myaddr, len)
493 return target_xfer_memory (memaddr, myaddr, len, 0);
496 /* Read LEN bytes of target memory at address MEMADDR, placing the results
497 in GDB's memory at MYADDR. Returns a count of the bytes actually read,
498 and optionally an errno value in the location pointed to by ERRNOPTR
499 if ERRNOPTR is non-null. */
502 target_read_memory_partial (memaddr, myaddr, len, errnoptr)
508 int nread; /* Number of bytes actually read. */
509 int errcode; /* Error from last read. */
511 /* First try a complete read. */
512 errcode = target_xfer_memory (memaddr, myaddr, len, 0);
520 /* Loop, reading one byte at a time until we get as much as we can. */
521 for (errcode = 0, nread = 0; len > 0 && errcode == 0; nread++, len--)
523 errcode = target_xfer_memory (memaddr++, myaddr++, 1, 0);
525 /* If an error, the last read was unsuccessful, so adjust count. */
531 if (errnoptr != NULL)
539 target_write_memory (memaddr, myaddr, len)
544 return target_xfer_memory (memaddr, myaddr, len, 1);
547 /* Move memory to or from the targets. Iterate until all of it has
548 been moved, if necessary. The top target gets priority; anything
549 it doesn't want, is offered to the next one down, etc. Note the
550 business with curlen: if an early target says "no, but I have a
551 boundary overlapping this xfer" then we shorten what we offer to
552 the subsequent targets so the early guy will get a chance at the
553 tail before the subsequent ones do.
555 Result is 0 or errno value. */
558 target_xfer_memory (memaddr, myaddr, len, write)
566 struct target_ops *t;
568 /* to_xfer_memory is not guaranteed to set errno, even when it returns
572 /* The quick case is that the top target does it all. */
573 res = current_target->to_xfer_memory
574 (memaddr, myaddr, len, write, current_target);
580 /* If res <= 0 then we call it again in the loop. Ah well. */
584 curlen = len; /* Want to do it all */
585 for (t = current_target;
587 t = t->to_has_all_memory? 0: t->to_next)
589 res = t->to_xfer_memory(memaddr, myaddr, curlen, write, t);
590 if (res > 0) break; /* Handled all or part of xfer */
591 if (res == 0) continue; /* Handled none */
592 curlen = -res; /* Could handle once we get past res bytes */
596 /* If this address is for nonexistent memory,
597 read zeros if reading, or do nothing if writing. Return error. */
599 memset (myaddr, 0, len);
610 return 0; /* We managed to cover it all somehow. */
616 target_info (args, from_tty)
620 struct target_ops *t;
623 if (symfile_objfile != NULL)
624 printf ("Symbols from \"%s\".\n", symfile_objfile->name);
626 #ifdef FILES_INFO_HOOK
627 if (FILES_INFO_HOOK ())
631 for (t = current_target;
635 if ((int)(t->to_stratum) <= (int)dummy_stratum)
638 printf("\tWhile running this, gdb does not access memory from...\n");
639 printf("%s:\n", t->to_longname);
640 (t->to_files_info)(t);
641 has_all_mem = t->to_has_all_memory;
645 /* This is to be called by the open routine before it does
649 target_preopen (from_tty)
654 if (target_has_execution)
656 if (query ("A program is being debugged already. Kill it? "))
659 error ("Program not killed.");
663 /* Detach a target after doing deferred register stores. */
666 target_detach (args, from_tty)
670 /* Handle any optimized stores to the inferior. */
671 #ifdef DO_DEFERRED_STORES
674 (current_target->to_detach) (args, from_tty);
676 /* It is correct to do this because the top process can never be as high
677 as process_stratum now. This is needed at least in the case where
678 we detach a corefile, and thus need to flush the frame cache. */
679 generic_mourn_inferior ();
682 /* Look through the list of possible targets for a target that can
683 execute a run or attach command without any other data. This is
684 used to locate the default process stratum.
686 Result is always valid (error() is called for errors). */
688 static struct target_ops *
689 find_default_run_target (do_mesg)
692 struct target_ops **t;
693 struct target_ops *runable = NULL;
698 for (t = target_structs; t < target_structs + target_struct_size;
701 if (target_can_run(*t))
709 error ("Don't know how to %s. Try \"help target\".", do_mesg);
715 find_default_attach (args, from_tty)
719 struct target_ops *t;
721 t = find_default_run_target("attach");
722 (t->to_attach) (args, from_tty);
727 find_default_create_inferior (exec_file, allargs, env)
732 struct target_ops *t;
734 t = find_default_run_target("run");
735 (t->to_create_inferior) (exec_file, allargs, env);
748 struct target_ops **t;
749 struct target_ops *runable = NULL;
754 for (t = target_structs; t < target_structs + target_struct_size;
757 if ((*t)->to_stratum == core_stratum)
764 return(count == 1 ? runable : NULL);
767 /* Convert a normal process ID to a string. Returns the string in a static
771 normal_pid_to_str (pid)
776 sprintf (buf, "process %d", pid);
781 static char targ_desc[] =
782 "Names of targets and files being debugged.\n\
783 Shows the entire stack of targets currently in use (including the exec-file,\n\
784 core-file, and process, if any), as well as the symbol file name.";
787 _initialize_targets ()
789 current_target = &dummy_target;
790 cleanup_target (current_target);
792 add_info ("target", target_info, targ_desc);
793 add_info ("files", target_info, targ_desc);