xref: /dragonfly/contrib/gdb-7/gdb/fbsd-nat.c (revision fcf53d9b)
1 /* Native-dependent code for FreeBSD.
2 
3    Copyright (C) 2002, 2003, 2004, 2007, 2008, 2009
4    Free Software Foundation, Inc.
5 
6    This file is part of GDB.
7 
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 3 of the License, or
11    (at your option) any later version.
12 
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17 
18    You should have received a copy of the GNU General Public License
19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
20 
21 #include "defs.h"
22 #include "gdbcore.h"
23 #include "inferior.h"
24 #include "regcache.h"
25 #include "regset.h"
26 #include "gdbthread.h"
27 
28 #include "gdb_assert.h"
29 #include "gdb_string.h"
30 #include <sys/types.h>
31 #include <sys/procfs.h>
32 #include <sys/sysctl.h>
33 
34 #include "elf-bfd.h"
35 #include "fbsd-nat.h"
36 
37 /* Return a the name of file that can be opened to get the symbols for
38    the child process identified by PID.  */
39 
40 char *
41 fbsd_pid_to_exec_file (int pid)
42 {
43   size_t len = MAXPATHLEN;
44   char *buf = xcalloc (len, sizeof (char));
45   char *path;
46 
47 #ifdef KERN_PROC_PATHNAME
48   int mib[4];
49 
50   mib[0] = CTL_KERN;
51   mib[1] = KERN_PROC;
52   mib[2] = KERN_PROC_PATHNAME;
53   mib[3] = pid;
54   if (sysctl (mib, 4, buf, &len, NULL, 0) == 0)
55     return buf;
56 #endif
57 
58   path = xstrprintf ("/proc/%d/file", pid);
59   if (readlink (path, buf, MAXPATHLEN) == -1)
60     {
61       xfree (buf);
62       buf = NULL;
63     }
64 
65   xfree (path);
66   return buf;
67 }
68 
69 static int
70 fbsd_read_mapping (FILE *mapfile, unsigned long *start, unsigned long *end,
71 		   char *protection)
72 {
73   /* FreeBSD 5.1-RELEASE uses a 256-byte buffer.  */
74   char buf[256];
75   int resident, privateresident;
76   unsigned long obj;
77   int ret = EOF;
78 
79   /* As of FreeBSD 5.0-RELEASE, the layout is described in
80      /usr/src/sys/fs/procfs/procfs_map.c.  Somewhere in 5.1-CURRENT a
81      new column was added to the procfs map.  Therefore we can't use
82      fscanf since we need to support older releases too.  */
83   if (fgets (buf, sizeof buf, mapfile) != NULL)
84     ret = sscanf (buf, "%lx %lx %d %d %lx %s", start, end,
85 		  &resident, &privateresident, &obj, protection);
86 
87   return (ret != 0 && ret != EOF);
88 }
89 
90 /* Iterate over all the memory regions in the current inferior,
91    calling FUNC for each memory region.  OBFD is passed as the last
92    argument to FUNC.  */
93 
94 int
95 fbsd_find_memory_regions (int (*func) (CORE_ADDR, unsigned long,
96 				       int, int, int, void *),
97 			  void *obfd)
98 {
99   pid_t pid = ptid_get_pid (inferior_ptid);
100   char *mapfilename;
101   FILE *mapfile;
102   unsigned long start, end, size;
103   char protection[4];
104   int read, write, exec;
105   struct cleanup *cleanup;
106 
107   mapfilename = xstrprintf ("/proc/%ld/map", (long) pid);
108   cleanup = make_cleanup (xfree, mapfilename);
109   mapfile = fopen (mapfilename, "r");
110   if (mapfile == NULL)
111     error (_("Couldn't open %s."), mapfilename);
112   make_cleanup_fclose (mapfile);
113 
114   if (info_verbose)
115     fprintf_filtered (gdb_stdout,
116 		      "Reading memory regions from %s\n", mapfilename);
117 
118   /* Now iterate until end-of-file.  */
119   while (fbsd_read_mapping (mapfile, &start, &end, &protection[0]))
120     {
121       size = end - start;
122 
123       read = (strchr (protection, 'r') != 0);
124       write = (strchr (protection, 'w') != 0);
125       exec = (strchr (protection, 'x') != 0);
126 
127       if (info_verbose)
128 	{
129 	  fprintf_filtered (gdb_stdout,
130 			    "Save segment, %ld bytes at %s (%c%c%c)\n",
131 			    size, paddress (target_gdbarch, start),
132 			    read ? 'r' : '-',
133 			    write ? 'w' : '-',
134 			    exec ? 'x' : '-');
135 	}
136 
137       /* Invoke the callback function to create the corefile segment. */
138       func (start, size, read, write, exec, obfd);
139     }
140 
141   do_cleanups (cleanup);
142   return 0;
143 }
144 
145 static int
146 find_signalled_thread (struct thread_info *info, void *data)
147 {
148   if (info->stop_signal != TARGET_SIGNAL_0
149       && ptid_get_pid (info->ptid) == ptid_get_pid (inferior_ptid))
150     return 1;
151 
152   return 0;
153 }
154 
155 static enum target_signal
156 find_stop_signal (void)
157 {
158   struct thread_info *info =
159     iterate_over_threads (find_signalled_thread, NULL);
160 
161   if (info)
162     return info->stop_signal;
163   else
164     return TARGET_SIGNAL_0;
165 }
166 
167 /* Create appropriate note sections for a corefile, returning them in
168    allocated memory.  */
169 
170 char *
171 fbsd_make_corefile_notes (bfd *obfd, int *note_size)
172 {
173   const struct regcache *regcache = get_current_regcache ();
174   struct gdbarch *gdbarch = get_regcache_arch (regcache);
175   gregset_t gregs;
176   fpregset_t fpregs;
177   char *note_data = NULL;
178   Elf_Internal_Ehdr *i_ehdrp;
179   const struct regset *regset;
180   size_t size;
181 
182   /* Put a "FreeBSD" label in the ELF header.  */
183   i_ehdrp = elf_elfheader (obfd);
184   i_ehdrp->e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
185 
186   gdb_assert (gdbarch_regset_from_core_section_p (gdbarch));
187 
188   size = sizeof gregs;
189   regset = gdbarch_regset_from_core_section (gdbarch, ".reg", size);
190   gdb_assert (regset && regset->collect_regset);
191   regset->collect_regset (regset, regcache, -1, &gregs, size);
192 
193   note_data = elfcore_write_prstatus (obfd, note_data, note_size,
194 				      ptid_get_pid (inferior_ptid),
195 				      find_stop_signal (), &gregs);
196 
197   size = sizeof fpregs;
198   regset = gdbarch_regset_from_core_section (gdbarch, ".reg2", size);
199   gdb_assert (regset && regset->collect_regset);
200   regset->collect_regset (regset, regcache, -1, &fpregs, size);
201 
202   note_data = elfcore_write_prfpreg (obfd, note_data, note_size,
203 				     &fpregs, sizeof (fpregs));
204 
205   if (get_exec_file (0))
206     {
207       char *fname = strrchr (get_exec_file (0), '/') + 1;
208       char *psargs = xstrdup (fname);
209 
210       if (get_inferior_args ())
211 	psargs = reconcat (psargs, psargs, " ", get_inferior_args (), NULL);
212 
213       note_data = elfcore_write_prpsinfo (obfd, note_data, note_size,
214 					  fname, psargs);
215     }
216 
217   make_cleanup (xfree, note_data);
218   return note_data;
219 }
220