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