gnu/usr.bin/gdb/kgdb/trgt.c

   1 /*
   2  * Copyright (c) 2004 Marcel Moolenaar
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  *
  26  * $FreeBSD: src/gnu/usr.bin/gdb/kgdb/trgt.c,v 1.12 2008/05/01 20:36:48 jhb Exp $
  27  */
  28
  29 #include <sys/cdefs.h>
  30
  31 #include <sys/param.h>
  32 #include <sys/sysctl.h>
  33 #include <sys/user.h>
  34 #include <err.h>
  35 #include <fcntl.h>
  36 #include <kvm.h>
  37
  38 #include <defs.h>
  39 #include <readline/readline.h>
  40 #include <readline/tilde.h>
  41 #include <command.h>
  42 #include <exec.h>
  43 #include <frame-unwind.h>
  44 #include <gdb.h>
  45 #include <gdbcore.h>
  46 #include <gdbthread.h>
  47 #include <inferior.h>
  48 #include <language.h>
  49 #include <regcache.h>
  50 #include <solib.h>
  51 #include <target.h>
  52 #include <ui-out.h>
  53 #include <observer.h>
  54
  55 #include "kgdb.h"
  56
  57 static void     kgdb_core_cleanup(void *);
  58
  59 static char *vmcore;
  60 static struct target_ops kgdb_trgt_ops;
  61
  62 kvm_t *kvm;
  63 static char kvm_err[_POSIX2_LINE_MAX];
  64
  65 #define KERNOFF         (kgdb_kernbase ())
  66 #define INKERNEL(x)     ((x) >= KERNOFF)
  67
  68 static CORE_ADDR
  69 kgdb_kernbase (void)
  70 {
  71         static CORE_ADDR kernbase;
  72         struct minimal_symbol *sym;
  73
  74         if (kernbase == 0) {
  75                 sym = lookup_minimal_symbol ("kernbase", NULL, NULL);
  76                 if (sym == NULL) {
  77                         kernbase = KERNBASE;
  78                 } else {
  79                         kernbase = SYMBOL_VALUE_ADDRESS (sym);
  80                 }
  81         }
  82         return kernbase;
  83 }
  84
  85 static void
  86 kgdb_trgt_open(char *filename, int from_tty)
  87 {
  88         struct cleanup *old_chain;
  89         struct thread_info *ti;
  90         struct kthr *kt;
  91         kvm_t *nkvm;
  92         char *temp;
  93         int ontop;
  94
  95         target_preopen (from_tty);
  96         if (!filename)
  97                 error ("No vmcore file specified.");
  98         if (!exec_bfd)
  99                 error ("Can't open a vmcore without a kernel");
 100
 101         filename = tilde_expand (filename);
 102         if (filename[0] != '/') {
 103                 temp = concat (current_directory, "/", filename, NULL);
 104                 xfree(filename);
 105                 filename = temp;
 106         }
 107
 108         old_chain = make_cleanup (xfree, filename);
 109
 110         nkvm = kvm_openfiles(bfd_get_filename(exec_bfd), filename, NULL,
 111             write_files ? O_RDWR : O_RDONLY, kvm_err);
 112         if (nkvm == NULL)
 113                 error ("Failed to open vmcore: %s", kvm_err);
 114
 115         /* Don't free the filename now and close any previous vmcore. */
 116         discard_cleanups(old_chain);
 117         unpush_target(&kgdb_trgt_ops);
 118
 119         kvm = nkvm;
 120         vmcore = filename;
 121         old_chain = make_cleanup(kgdb_core_cleanup, NULL);
 122
 123         ontop = !push_target (&kgdb_trgt_ops);
 124         discard_cleanups (old_chain);
 125
 126         kgdb_dmesg();
 127
 128         init_thread_list();
 129         kt = kgdb_thr_init();
 130         while (kt != NULL) {
 131                 if (!in_inferior_list(kt->pid))
 132                         add_inferior(kt->pid);
 133                 ti = add_thread_silent(ptid_build(kt->pid, 0, kt->tid));
 134                 kt = kgdb_thr_next(kt);
 135         }
 136         if (curkthr != 0)
 137                 inferior_ptid = ptid_build(curkthr->pid, 0, curkthr->tid);
 138
 139         frame_unwind_prepend_unwinder(get_frame_arch(get_current_frame()), &kgdb_trgt_trapframe_unwind);
 140
 141         if (ontop) {
 142                 /* XXX: fetch registers? */
 143                 kld_init();
 144                 reinit_frame_cache();
 145                 select_frame (get_current_frame());
 146                 print_stack_frame(get_selected_frame(NULL),
 147                     frame_relative_level(get_selected_frame(NULL)), 1);
 148         } else
 149                 warning(
 150         "you won't be able to access this vmcore until you terminate\n\
 151 your %s; do ``info files''", target_longname);
 152 }
 153
 154 static void
 155 kgdb_trgt_close(int quitting)
 156 {
 157
 158         if (kvm != NULL) {
 159                 inferior_ptid = null_ptid;
 160                 clear_solib();
 161                 if (kvm_close(kvm) != 0)
 162                         warning("cannot close \"%s\": %s", vmcore,
 163                             kvm_geterr(kvm));
 164                 kvm = NULL;
 165                 xfree(vmcore);
 166                 vmcore = NULL;
 167         }
 168 }
 169
 170 static void
 171 kgdb_core_cleanup(void *arg)
 172 {
 173
 174         kgdb_trgt_close(0);
 175 }
 176
 177 static void
 178 kgdb_trgt_detach(struct target_ops *target, char *args, int from_tty)
 179 {
 180
 181         if (args)
 182                 error ("Too many arguments");
 183         unpush_target(target);
 184         reinit_frame_cache();
 185         if (from_tty)
 186                 printf_filtered("No vmcore file now.\n");
 187 }
 188
 189 static char *
 190 kgdb_trgt_extra_thread_info(struct thread_info *ti)
 191 {
 192
 193         return (kgdb_thr_extra_thread_info(ptid_get_tid(ti->ptid)));
 194 }
 195
 196 static void
 197 kgdb_trgt_files_info(struct target_ops *target)
 198 {
 199
 200         printf_filtered ("\t`%s', ", vmcore);
 201         wrap_here ("        ");
 202         printf_filtered ("file type %s.\n", "DragonFly kernel vmcore");
 203 }
 204
 205 static void
 206 kgdb_trgt_find_new_threads(struct target_ops *target_ops)
 207 {
 208         struct target_ops *tb;
 209
 210         if (kvm != NULL)
 211                 return;
 212
 213         tb = find_target_beneath(target_ops);
 214         if (tb->to_find_new_threads != NULL)
 215                 tb->to_find_new_threads(target_ops);
 216 }
 217
 218 static char *
 219 kgdb_trgt_pid_to_str(struct target_ops *target_ops __unused, ptid_t ptid)
 220 {
 221         return (kgdb_thr_pid_to_str(ptid));
 222 }
 223
 224 static int
 225 kgdb_trgt_thread_alive(struct target_ops *target_ops __unused, ptid_t ptid)
 226 {
 227         return (kgdb_thr_lookup_tid(ptid_get_tid(ptid)) != NULL);
 228 }
 229
 230 static LONGEST
 231 kgdb_trgt_xfer_partial(struct target_ops *ops, enum target_object object,
 232                        const char *annex, gdb_byte *readbuf,
 233                        const gdb_byte *writebuf,
 234                        ULONGEST offset, LONGEST len)
 235 {
 236         if (kvm != NULL) {
 237                 if (len == 0)
 238                         return (0);
 239                 if (writebuf != NULL)
 240                         return (kvm_write(kvm, offset, writebuf, len));
 241                 if (readbuf != NULL)
 242                         return (kvm_read(kvm, offset, readbuf, len));
 243         }
 244         return (ops->beneath->to_xfer_partial(ops->beneath, object, annex,
 245                                               readbuf, writebuf, offset, len));
 246 }
 247
 248 static void
 249 kgdb_switch_to_thread(struct kthr *thr)
 250 {
 251         char buf[16];
 252         int thread_id;
 253         char *err;
 254
 255         thread_id = pid_to_thread_id(ptid_build(thr->pid, 0, thr->tid));
 256         if (thread_id == 0)
 257                 error ("invalid tid");
 258         snprintf(buf, sizeof(buf), "%d", thread_id);
 259         if (!gdb_thread_select(uiout, buf, &err))
 260                 error ("%s", err);
 261 }
 262
 263 static void
 264 kgdb_set_proc_cmd (char *arg, int from_tty)
 265 {
 266         CORE_ADDR addr;
 267         struct kthr *thr;
 268
 269         if (!arg)
 270                 error_no_arg ("proc address for the new context");
 271
 272         if (kvm == NULL)
 273                 error ("only supported for core file target");
 274
 275         addr = (CORE_ADDR) parse_and_eval_address (arg);
 276
 277         if (!INKERNEL (addr)) {
 278                 thr = kgdb_thr_lookup_pid((int)addr);
 279                 if (thr == NULL)
 280                         error ("invalid pid");
 281         } else {
 282                 thr = kgdb_thr_lookup_paddr(addr);
 283                 if (thr == NULL)
 284                         error("invalid proc address");
 285         }
 286         kgdb_switch_to_thread(thr);
 287 }
 288
 289 static void
 290 kgdb_set_tid_cmd (char *arg, int from_tty)
 291 {
 292         CORE_ADDR addr;
 293         struct kthr *thr;
 294
 295         if (!arg)
 296                 error_no_arg ("Thread address for the new context");
 297
 298         addr = (CORE_ADDR) parse_and_eval_address (arg);
 299         thr = kgdb_thr_lookup_taddr(addr);
 300
 301         if (thr == NULL)
 302                 error("invalid thread address");
 303
 304         kgdb_switch_to_thread(thr);
 305 }
 306
 307 int fbsdcoreops_suppress_target = 1;
 308
 309 void
 310 initialize_kgdb_target(void)
 311 {
 312         kgdb_trgt_ops.to_magic = OPS_MAGIC;
 313         kgdb_trgt_ops.to_shortname = "kernel";
 314         kgdb_trgt_ops.to_longname = "kernel core dump file";
 315         kgdb_trgt_ops.to_doc =
 316     "Use a vmcore file as a target.  Specify the filename of the vmcore file.";
 317         kgdb_trgt_ops.to_stratum = core_stratum;
 318         kgdb_trgt_ops.to_has_registers = default_child_has_registers;
 319         kgdb_trgt_ops.to_has_memory = default_child_has_memory;
 320         kgdb_trgt_ops.to_has_stack = default_child_has_stack;
 321
 322         kgdb_trgt_ops.to_open = kgdb_trgt_open;
 323         kgdb_trgt_ops.to_close = kgdb_trgt_close;
 324         kgdb_trgt_ops.to_attach = find_default_attach;
 325         kgdb_trgt_ops.to_detach = kgdb_trgt_detach;
 326         kgdb_trgt_ops.to_extra_thread_info = kgdb_trgt_extra_thread_info;
 327         kgdb_trgt_ops.to_fetch_registers = kgdb_trgt_fetch_registers;
 328         kgdb_trgt_ops.to_files_info = kgdb_trgt_files_info;
 329         kgdb_trgt_ops.to_find_new_threads = kgdb_trgt_find_new_threads;
 330         kgdb_trgt_ops.to_pid_to_str = kgdb_trgt_pid_to_str;
 331         /*
 332         kgdb_trgt_ops.to_store_registers = NULL;
 333         */
 334         kgdb_trgt_ops.to_thread_alive = kgdb_trgt_thread_alive;
 335         kgdb_trgt_ops.to_xfer_partial = kgdb_trgt_xfer_partial;
 336         add_target(&kgdb_trgt_ops);
 337
 338         add_com ("proc", class_obscure, kgdb_set_proc_cmd,
 339            "Set current process context");
 340         add_com ("tid", class_obscure, kgdb_set_tid_cmd,
 341            "Set current thread context");
 342 }