gdb/fbsd-nat.c

   1 /* Native-dependent code for FreeBSD.
   2
   3    Copyright (C) 2002, 2003, 2004, 2007, 2008 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   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 3 of the License, or
  10    (at your option) any later version.
  11
  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.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "gdbcore.h"
  22 #include "inferior.h"
  23 #include "regcache.h"
  24 #include "regset.h"
  25 #include "gdbthread.h"
  26
  27 #include "gdb_assert.h"
  28 #include "gdb_string.h"
  29 #include <sys/types.h>
  30 #include <sys/procfs.h>
  31 #include <sys/sysctl.h>
  32
  33 #include "elf-bfd.h"
  34 #include "fbsd-nat.h"
  35
  36 /* Return a the name of file that can be opened to get the symbols for
  37    the child process identified by PID.  */
  38
  39 char *
  40 fbsd_pid_to_exec_file (int pid)
  41 {
  42   size_t len = MAXPATHLEN;
  43   char *buf = xcalloc (len, sizeof (char));
  44   char *path;
  45
  46 #ifdef KERN_PROC_PATHNAME
  47   int mib[4];
  48
  49   mib[0] = CTL_KERN;
  50   mib[1] = KERN_PROC;
  51   mib[2] = KERN_PROC_PATHNAME;
  52   mib[3] = pid;
  53   if (sysctl (mib, 4, buf, &len, NULL, 0) == 0)
  54     return buf;
  55 #endif
  56
  57   path = xstrprintf ("/proc/%d/file", pid);
  58   if (readlink (path, buf, MAXPATHLEN) == -1)
  59     {
  60       xfree (buf);
  61       buf = NULL;
  62     }
  63
  64   xfree (path);
  65   return buf;
  66 }
  67
  68 static int
  69 fbsd_read_mapping (FILE *mapfile, unsigned long *start, unsigned long *end,
  70                    char *protection)
  71 {
  72   /* FreeBSD 5.1-RELEASE uses a 256-byte buffer.  */
  73   char buf[256];
  74   int resident, privateresident;
  75   unsigned long obj;
  76   int ret = EOF;
  77
  78   /* As of FreeBSD 5.0-RELEASE, the layout is described in
  79      /usr/src/sys/fs/procfs/procfs_map.c.  Somewhere in 5.1-CURRENT a
  80      new column was added to the procfs map.  Therefore we can't use
  81      fscanf since we need to support older releases too.  */
  82   if (fgets (buf, sizeof buf, mapfile) != NULL)
  83     ret = sscanf (buf, "%lx %lx %d %d %lx %s", start, end,
  84                   &resident, &privateresident, &obj, protection);
  85
  86   return (ret != 0 && ret != EOF);
  87 }
  88
  89 /* Iterate over all the memory regions in the current inferior,
  90    calling FUNC for each memory region.  OBFD is passed as the last
  91    argument to FUNC.  */
  92
  93 int
  94 fbsd_find_memory_regions (int (*func) (CORE_ADDR, unsigned long,
  95                                        int, int, int, void *),
  96                           void *obfd)
  97 {
  98   pid_t pid = ptid_get_pid (inferior_ptid);
  99   char *mapfilename;
 100   FILE *mapfile;
 101   unsigned long start, end, size;
 102   char protection[4];
 103   int read, write, exec;
 104
 105   mapfilename = xstrprintf ("/proc/%ld/map", (long) pid);
 106   mapfile = fopen (mapfilename, "r");
 107   if (mapfile == NULL)
 108     error (_("Couldn't open %s."), mapfilename);
 109
 110   if (info_verbose)
 111     fprintf_filtered (gdb_stdout,
 112                       "Reading memory regions from %s\n", mapfilename);
 113
 114   /* Now iterate until end-of-file.  */
 115   while (fbsd_read_mapping (mapfile, &start, &end, &protection[0]))
 116     {
 117       size = end - start;
 118
 119       read = (strchr (protection, 'r') != 0);
 120       write = (strchr (protection, 'w') != 0);
 121       exec = (strchr (protection, 'x') != 0);
 122
 123       if (info_verbose)
 124         {
 125           fprintf_filtered (gdb_stdout,
 126                             "Save segment, %ld bytes at 0x%s (%c%c%c)\n",
 127                             size, paddr_nz (start),
 128                             read ? 'r' : '-',
 129                             write ? 'w' : '-',
 130                             exec ? 'x' : '-');
 131         }
 132
 133       /* Invoke the callback function to create the corefile segment. */
 134       func (start, size, read, write, exec, obfd);
 135     }
 136
 137   fclose (mapfile);
 138   return 0;
 139 }
 140
 141 static int
 142 find_signalled_thread (struct thread_info *info, void *data)
 143 {
 144   if (info->stop_signal != TARGET_SIGNAL_0
 145       && ptid_get_pid (info->ptid) == ptid_get_pid (inferior_ptid))
 146     return 1;
 147
 148   return 0;
 149 }
 150
 151 static enum target_signal
 152 find_stop_signal (void)
 153 {
 154   struct thread_info *info =
 155     iterate_over_threads (find_signalled_thread, NULL);
 156
 157   if (info)
 158     return info->stop_signal;
 159   else
 160     return TARGET_SIGNAL_0;
 161 }
 162
 163 /* Create appropriate note sections for a corefile, returning them in
 164    allocated memory.  */
 165
 166 char *
 167 fbsd_make_corefile_notes (bfd *obfd, int *note_size)
 168 {
 169   const struct regcache *regcache = get_current_regcache ();
 170   struct gdbarch *gdbarch = get_regcache_arch (regcache);
 171   gregset_t gregs;
 172   fpregset_t fpregs;
 173   char *note_data = NULL;
 174   Elf_Internal_Ehdr *i_ehdrp;
 175   const struct regset *regset;
 176   size_t size;
 177
 178   /* Put a "FreeBSD" label in the ELF header.  */
 179   i_ehdrp = elf_elfheader (obfd);
 180   i_ehdrp->e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
 181
 182   gdb_assert (gdbarch_regset_from_core_section_p (gdbarch));
 183
 184   size = sizeof gregs;
 185   regset = gdbarch_regset_from_core_section (gdbarch, ".reg", size);
 186   gdb_assert (regset && regset->collect_regset);
 187   regset->collect_regset (regset, regcache, -1, &gregs, size);
 188
 189   note_data = elfcore_write_prstatus (obfd, note_data, note_size,
 190                                       ptid_get_pid (inferior_ptid),
 191                                       find_stop_signal (), &gregs);
 192
 193   size = sizeof fpregs;
 194   regset = gdbarch_regset_from_core_section (gdbarch, ".reg2", size);
 195   gdb_assert (regset && regset->collect_regset);
 196   regset->collect_regset (regset, regcache, -1, &fpregs, size);
 197
 198   note_data = elfcore_write_prfpreg (obfd, note_data, note_size,
 199                                      &fpregs, sizeof (fpregs));
 200
 201   if (get_exec_file (0))
 202     {
 203       char *fname = strrchr (get_exec_file (0), '/') + 1;
 204       char *psargs = xstrdup (fname);
 205
 206       if (get_inferior_args ())
 207         psargs = reconcat (psargs, psargs, " ", get_inferior_args (), NULL);
 208
 209       note_data = elfcore_write_prpsinfo (obfd, note_data, note_size,
 210                                           fname, psargs);
 211     }
 212
 213   make_cleanup (xfree, note_data);
 214   return note_data;
 215 }