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
  27 #include <sys/cdefs.h>
  28 __FBSDID("$FreeBSD$");
  29
  30 #include <sys/param.h>
  31 #include <sys/proc.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
  54 #include "kgdb.h"
  55
  56 static void     kgdb_core_cleanup(void *);
  57
  58 static char *vmcore;
  59 static struct target_ops kgdb_trgt_ops;
  60
  61 kvm_t *kvm;
  62 static char kvm_err[_POSIX2_LINE_MAX];
  63
  64 #define KERNOFF         (kgdb_kernbase ())
  65 #define INKERNEL(x)     ((x) >= KERNOFF)
  66
  67 static CORE_ADDR
  68 kgdb_kernbase (void)
  69 {
  70         static CORE_ADDR kernbase;
  71         struct minimal_symbol *sym;
  72
  73         if (kernbase == 0) {
  74                 sym = lookup_minimal_symbol ("kernbase", NULL, NULL);
  75                 if (sym == NULL) {
  76                         kernbase = KERNBASE;
  77                 } else {
  78                         kernbase = SYMBOL_VALUE_ADDRESS (sym);
  79                 }
  80         }
  81         return kernbase;
  82 }
  83
  84 static void
  85 kgdb_trgt_open(char *filename, int from_tty)
  86 {
  87         struct cleanup *old_chain;
  88         struct thread_info *ti;
  89         struct kthr *kt;
  90         kvm_t *nkvm;
  91         char *temp;
  92         int ontop;
  93
  94         target_preopen (from_tty);
  95         if (!filename)
  96                 error ("No vmcore file specified.");
  97         if (!exec_bfd)
  98                 error ("Can't open a vmcore without a kernel");
  99
 100         filename = tilde_expand (filename);
 101         if (filename[0] != '/') {
 102                 temp = concat (current_directory, "/", filename, NULL);
 103                 xfree(filename);
 104                 filename = temp;
 105         }
 106
 107         old_chain = make_cleanup (xfree, filename);
 108
 109         nkvm = kvm_openfiles(bfd_get_filename(exec_bfd), filename, NULL,
 110             write_files ? O_RDWR : O_RDONLY, kvm_err);
 111         if (nkvm == NULL)
 112                 error ("Failed to open vmcore: %s", kvm_err);
 113
 114         /* Don't free the filename now and close any previous vmcore. */
 115         discard_cleanups(old_chain);
 116         unpush_target(&kgdb_trgt_ops);
 117
 118         kvm = nkvm;
 119         vmcore = filename;
 120         old_chain = make_cleanup(kgdb_core_cleanup, NULL);
 121
 122         ontop = !push_target (&kgdb_trgt_ops);
 123         discard_cleanups (old_chain);
 124
 125         kgdb_dmesg();
 126
 127         init_thread_list();
 128         kt = kgdb_thr_init();
 129         while (kt != NULL) {
 130                 ti = add_thread(pid_to_ptid(kt->tid));
 131                 kt = kgdb_thr_next(kt);
 132         }
 133         if (curkthr != 0)
 134                 inferior_ptid = pid_to_ptid(curkthr->tid);
 135
 136         if (ontop) {
 137                 /* XXX: fetch registers? */
 138                 kld_init();
 139                 flush_cached_frames();
 140                 select_frame (get_current_frame());
 141                 print_stack_frame(get_selected_frame(),
 142                     frame_relative_level(get_selected_frame()), 1);
 143         } else
 144                 warning(
 145         "you won't be able to access this vmcore until you terminate\n\
 146 your %s; do ``info files''", target_longname);
 147 }
 148
 149 static void
 150 kgdb_trgt_close(int quitting)
 151 {
 152
 153         if (kvm != NULL) {
 154                 inferior_ptid = null_ptid;
 155                 CLEAR_SOLIB();
 156                 if (kvm_close(kvm) != 0)
 157                         warning("cannot close \"%s\": %s", vmcore,
 158                             kvm_geterr(kvm));
 159                 kvm = NULL;
 160                 xfree(vmcore);
 161                 vmcore = NULL;
 162                 if (kgdb_trgt_ops.to_sections) {
 163                         xfree(kgdb_trgt_ops.to_sections);
 164                         kgdb_trgt_ops.to_sections = NULL;
 165                         kgdb_trgt_ops.to_sections_end = NULL;
 166                 }
 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(char *args, int from_tty)
 179 {
 180
 181         if (args)
 182                 error ("Too many arguments");
 183         unpush_target(&kgdb_trgt_ops);
 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_pid(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", "FreeBSD kernel vmcore");
 203 }
 204
 205 static void
 206 kgdb_trgt_find_new_threads(void)
 207 {
 208         struct target_ops *tb;
 209
 210         if (kvm != NULL)
 211                 return;
 212
 213         tb = find_target_beneath(&kgdb_trgt_ops);
 214         if (tb->to_find_new_threads != NULL)
 215                 tb->to_find_new_threads();
 216 }
 217
 218 static char *
 219 kgdb_trgt_pid_to_str(ptid_t ptid)
 220 {
 221         static char buf[33];
 222
 223         snprintf(buf, sizeof(buf), "Thread %d", ptid_get_pid(ptid));
 224         return (buf);
 225 }
 226
 227 static int
 228 kgdb_trgt_thread_alive(ptid_t ptid)
 229 {
 230         return (kgdb_thr_lookup_tid(ptid_get_pid(ptid)) != NULL);
 231 }
 232
 233 static int
 234 kgdb_trgt_xfer_memory(CORE_ADDR memaddr, char *myaddr, int len, int write,
 235     struct mem_attrib *attrib, struct target_ops *target)
 236 {
 237         struct target_ops *tb;
 238
 239         if (kvm != NULL) {
 240                 if (len == 0)
 241                         return (0);
 242                 if (!write)
 243                         return (kvm_read(kvm, memaddr, myaddr, len));
 244                 else
 245                         return (kvm_write(kvm, memaddr, myaddr, len));
 246         }
 247         tb = find_target_beneath(target);
 248         return (tb->to_xfer_memory(memaddr, myaddr, len, write, attrib, tb));
 249 }
 250
 251 static int
 252 kgdb_trgt_ignore_breakpoints(CORE_ADDR addr, char *contents)
 253 {
 254
 255         return 0;
 256 }
 257
 258 static void
 259 kgdb_switch_to_thread(int tid)
 260 {
 261         char buf[16];
 262         int thread_id;
 263
 264         thread_id = pid_to_thread_id(pid_to_ptid(tid));
 265         if (thread_id == 0)
 266                 error ("invalid tid");
 267         snprintf(buf, sizeof(buf), "%d", thread_id);
 268         gdb_thread_select(uiout, buf);
 269 }
 270
 271 static void
 272 kgdb_set_proc_cmd (char *arg, int from_tty)
 273 {
 274         CORE_ADDR addr;
 275         struct kthr *thr;
 276
 277         if (!arg)
 278                 error_no_arg ("proc address for the new context");
 279
 280         if (kvm == NULL)
 281                 error ("only supported for core file target");
 282
 283         addr = (CORE_ADDR) parse_and_eval_address (arg);
 284
 285         if (!INKERNEL (addr)) {
 286                 thr = kgdb_thr_lookup_pid((int)addr);
 287                 if (thr == NULL)
 288                         error ("invalid pid");
 289         } else {
 290                 thr = kgdb_thr_lookup_paddr(addr);
 291                 if (thr == NULL)
 292                         error("invalid proc address");
 293         }
 294         kgdb_switch_to_thread(thr->tid);
 295 }
 296
 297 static void
 298 kgdb_set_tid_cmd (char *arg, int from_tty)
 299 {
 300         CORE_ADDR addr;
 301         struct kthr *thr;
 302
 303         if (!arg)
 304                 error_no_arg ("TID or thread address for the new context");
 305
 306         addr = (CORE_ADDR) parse_and_eval_address (arg);
 307
 308         if (kvm != NULL && INKERNEL (addr)) {
 309                 thr = kgdb_thr_lookup_taddr(addr);
 310                 if (thr == NULL)
 311                         error("invalid thread address");
 312                 addr = thr->tid;
 313         }
 314         kgdb_switch_to_thread(addr);
 315 }
 316
 317 int fbsdcoreops_suppress_target = 1;
 318
 319 void
 320 initialize_kgdb_target(void)
 321 {
 322
 323         kgdb_trgt_ops.to_magic = OPS_MAGIC;
 324         kgdb_trgt_ops.to_shortname = "kernel";
 325         kgdb_trgt_ops.to_longname = "kernel core dump file";
 326         kgdb_trgt_ops.to_doc =
 327     "Use a vmcore file as a target.  Specify the filename of the vmcore file.";
 328         kgdb_trgt_ops.to_stratum = core_stratum;
 329         kgdb_trgt_ops.to_has_memory = 1;
 330         kgdb_trgt_ops.to_has_registers = 1;
 331         kgdb_trgt_ops.to_has_stack = 1;
 332
 333         kgdb_trgt_ops.to_open = kgdb_trgt_open;
 334         kgdb_trgt_ops.to_close = kgdb_trgt_close;
 335         kgdb_trgt_ops.to_attach = find_default_attach;
 336         kgdb_trgt_ops.to_detach = kgdb_trgt_detach;
 337         kgdb_trgt_ops.to_extra_thread_info = kgdb_trgt_extra_thread_info;
 338         kgdb_trgt_ops.to_fetch_registers = kgdb_trgt_fetch_registers;
 339         kgdb_trgt_ops.to_files_info = kgdb_trgt_files_info;
 340         kgdb_trgt_ops.to_find_new_threads = kgdb_trgt_find_new_threads;
 341         kgdb_trgt_ops.to_pid_to_str = kgdb_trgt_pid_to_str;
 342         kgdb_trgt_ops.to_store_registers = kgdb_trgt_store_registers;
 343         kgdb_trgt_ops.to_thread_alive = kgdb_trgt_thread_alive;
 344         kgdb_trgt_ops.to_xfer_memory = kgdb_trgt_xfer_memory;
 345         kgdb_trgt_ops.to_insert_breakpoint = kgdb_trgt_ignore_breakpoints;
 346         kgdb_trgt_ops.to_remove_breakpoint = kgdb_trgt_ignore_breakpoints;
 347
 348         add_target(&kgdb_trgt_ops);
 349
 350         add_com ("proc", class_obscure, kgdb_set_proc_cmd,
 351            "Set current process context");
 352         add_com ("tid", class_obscure, kgdb_set_tid_cmd,
 353            "Set current thread context");
 354 }