summaryrefslogtreecommitdiff
path: root/gdb/inf-child.c
blob: 3db09c9e3accb9431ab835308484d69ce132d571 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
/* Default child (native) target interface, for GDB when running under
   Unix.

   Copyright (C) 1988-2013 Free Software Foundation, Inc.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"
#include "regcache.h"
#include "memattr.h"
#include "symtab.h"
#include "target.h"
#include "inferior.h"
#include <string.h>
#include <sys/stat.h>
#include "inf-child.h"
#include "gdb/fileio.h"
#include "agent.h"
#include "gdb_wait.h"
#include "filestuff.h"

#include <sys/types.h>
#include <fcntl.h>
#include <unistd.h>

/* Helper function for child_wait and the derivatives of child_wait.
   HOSTSTATUS is the waitstatus from wait() or the equivalent; store our
   translation of that in OURSTATUS.  */
void
store_waitstatus (struct target_waitstatus *ourstatus, int hoststatus)
{
  if (WIFEXITED (hoststatus))
    {
      ourstatus->kind = TARGET_WAITKIND_EXITED;
      ourstatus->value.integer = WEXITSTATUS (hoststatus);
    }
  else if (!WIFSTOPPED (hoststatus))
    {
      ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
      ourstatus->value.sig = gdb_signal_from_host (WTERMSIG (hoststatus));
    }
  else
    {
      ourstatus->kind = TARGET_WAITKIND_STOPPED;
      ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (hoststatus));
    }
}

/* Fetch register REGNUM from the inferior.  If REGNUM is -1, do this
   for all registers.  */

static void
inf_child_fetch_inferior_registers (struct target_ops *ops,
				    struct regcache *regcache, int regnum)
{
  if (regnum == -1)
    {
      for (regnum = 0;
	   regnum < gdbarch_num_regs (get_regcache_arch (regcache));
	   regnum++)
	regcache_raw_supply (regcache, regnum, NULL);
    }
  else
    regcache_raw_supply (regcache, regnum, NULL);
}

/* Store register REGNUM back into the inferior.  If REGNUM is -1, do
   this for all registers (including the floating point registers).  */

static void
inf_child_store_inferior_registers (struct target_ops *ops,
				    struct regcache *regcache, int regnum)
{
}

static void
inf_child_post_attach (int pid)
{
  /* This version of Unix doesn't require a meaningful "post attach"
     operation by a debugger.  */
}

/* Get ready to modify the registers array.  On machines which store
   individual registers, this doesn't need to do anything.  On
   machines which store all the registers in one fell swoop, this
   makes sure that registers contains all the registers from the
   program being debugged.  */

static void
inf_child_prepare_to_store (struct regcache *regcache)
{
}

static void
inf_child_open (char *arg, int from_tty)
{
  error (_("Use the \"run\" command to start a Unix child process."));
}

static void
inf_child_post_startup_inferior (ptid_t ptid)
{
  /* This version of Unix doesn't require a meaningful "post startup
     inferior" operation by a debugger.  */
}

static int
inf_child_follow_fork (struct target_ops *ops, int follow_child,
		       int detach_fork)
{
  /* This version of Unix doesn't support following fork or vfork
     events.  */
  return 0;
}

static int
inf_child_can_run (void)
{
  return 1;
}

static char *
inf_child_pid_to_exec_file (int pid)
{
  /* This version of Unix doesn't support translation of a process ID
     to the filename of the executable file.  */
  return NULL;
}


/* Target file operations.  */

static int
inf_child_fileio_open_flags_to_host (int fileio_open_flags, int *open_flags_p)
{
  int open_flags = 0;

  if (fileio_open_flags & ~FILEIO_O_SUPPORTED)
    return -1;

  if (fileio_open_flags & FILEIO_O_CREAT)
    open_flags |= O_CREAT;
  if (fileio_open_flags & FILEIO_O_EXCL)
    open_flags |= O_EXCL;
  if (fileio_open_flags & FILEIO_O_TRUNC)
    open_flags |= O_TRUNC;
  if (fileio_open_flags & FILEIO_O_APPEND)
    open_flags |= O_APPEND;
  if (fileio_open_flags & FILEIO_O_RDONLY)
    open_flags |= O_RDONLY;
  if (fileio_open_flags & FILEIO_O_WRONLY)
    open_flags |= O_WRONLY;
  if (fileio_open_flags & FILEIO_O_RDWR)
    open_flags |= O_RDWR;
/* On systems supporting binary and text mode, always open files in
   binary mode. */
#ifdef O_BINARY
  open_flags |= O_BINARY;
#endif

  *open_flags_p = open_flags;
  return 0;
}

static int
inf_child_errno_to_fileio_error (int errnum)
{
  switch (errnum)
    {
      case EPERM:
        return FILEIO_EPERM;
      case ENOENT:
        return FILEIO_ENOENT;
      case EINTR:
        return FILEIO_EINTR;
      case EIO:
        return FILEIO_EIO;
      case EBADF:
        return FILEIO_EBADF;
      case EACCES:
        return FILEIO_EACCES;
      case EFAULT:
        return FILEIO_EFAULT;
      case EBUSY:
        return FILEIO_EBUSY;
      case EEXIST:
        return FILEIO_EEXIST;
      case ENODEV:
        return FILEIO_ENODEV;
      case ENOTDIR:
        return FILEIO_ENOTDIR;
      case EISDIR:
        return FILEIO_EISDIR;
      case EINVAL:
        return FILEIO_EINVAL;
      case ENFILE:
        return FILEIO_ENFILE;
      case EMFILE:
        return FILEIO_EMFILE;
      case EFBIG:
        return FILEIO_EFBIG;
      case ENOSPC:
        return FILEIO_ENOSPC;
      case ESPIPE:
        return FILEIO_ESPIPE;
      case EROFS:
        return FILEIO_EROFS;
      case ENOSYS:
        return FILEIO_ENOSYS;
      case ENAMETOOLONG:
        return FILEIO_ENAMETOOLONG;
    }
  return FILEIO_EUNKNOWN;
}

/* Open FILENAME on the target, using FLAGS and MODE.  Return a
   target file descriptor, or -1 if an error occurs (and set
   *TARGET_ERRNO).  */
static int
inf_child_fileio_open (const char *filename, int flags, int mode,
		       int *target_errno)
{
  int nat_flags;
  int fd;

  if (inf_child_fileio_open_flags_to_host (flags, &nat_flags) == -1)
    {
      *target_errno = FILEIO_EINVAL;
      return -1;
    }

  /* We do not need to convert MODE, since the fileio protocol uses
     the standard values.  */
  fd = gdb_open_cloexec (filename, nat_flags, mode);
  if (fd == -1)
    *target_errno = inf_child_errno_to_fileio_error (errno);

  return fd;
}

/* Write up to LEN bytes from WRITE_BUF to FD on the target.
   Return the number of bytes written, or -1 if an error occurs
   (and set *TARGET_ERRNO).  */
static int
inf_child_fileio_pwrite (int fd, const gdb_byte *write_buf, int len,
			 ULONGEST offset, int *target_errno)
{
  int ret;

#ifdef HAVE_PWRITE
  ret = pwrite (fd, write_buf, len, (long) offset);
#else
  ret = -1;
#endif
  /* If we have no pwrite or it failed for this file, use lseek/write.  */
  if (ret == -1)
    {
      ret = lseek (fd, (long) offset, SEEK_SET);
      if (ret != -1)
	ret = write (fd, write_buf, len);
    }

  if (ret == -1)
    *target_errno = inf_child_errno_to_fileio_error (errno);

  return ret;
}

/* Read up to LEN bytes FD on the target into READ_BUF.
   Return the number of bytes read, or -1 if an error occurs
   (and set *TARGET_ERRNO).  */
static int
inf_child_fileio_pread (int fd, gdb_byte *read_buf, int len,
			ULONGEST offset, int *target_errno)
{
  int ret;

#ifdef HAVE_PREAD
  ret = pread (fd, read_buf, len, (long) offset);
#else
  ret = -1;
#endif
  /* If we have no pread or it failed for this file, use lseek/read.  */
  if (ret == -1)
    {
      ret = lseek (fd, (long) offset, SEEK_SET);
      if (ret != -1)
	ret = read (fd, read_buf, len);
    }

  if (ret == -1)
    *target_errno = inf_child_errno_to_fileio_error (errno);

  return ret;
}

/* Close FD on the target.  Return 0, or -1 if an error occurs
   (and set *TARGET_ERRNO).  */
static int
inf_child_fileio_close (int fd, int *target_errno)
{
  int ret;

  ret = close (fd);
  if (ret == -1)
    *target_errno = inf_child_errno_to_fileio_error (errno);

  return ret;
}

/* Unlink FILENAME on the target.  Return 0, or -1 if an error
   occurs (and set *TARGET_ERRNO).  */
static int
inf_child_fileio_unlink (const char *filename, int *target_errno)
{
  int ret;

  ret = unlink (filename);
  if (ret == -1)
    *target_errno = inf_child_errno_to_fileio_error (errno);

  return ret;
}

/* Read value of symbolic link FILENAME on the target.  Return a
   null-terminated string allocated via xmalloc, or NULL if an error
   occurs (and set *TARGET_ERRNO).  */
static char *
inf_child_fileio_readlink (const char *filename, int *target_errno)
{
  /* We support readlink only on systems that also provide a compile-time
     maximum path length (PATH_MAX), at least for now.  */
#if defined (HAVE_READLINK) && defined (PATH_MAX)
  char buf[PATH_MAX];
  int len;
  char *ret;

  len = readlink (filename, buf, sizeof buf);
  if (len < 0)
    {
      *target_errno = inf_child_errno_to_fileio_error (errno);
      return NULL;
    }

  ret = xmalloc (len + 1);
  memcpy (ret, buf, len);
  ret[len] = '\0';
  return ret;
#else
  *target_errno = FILEIO_ENOSYS;
  return NULL;
#endif
}

static int
inf_child_use_agent (int use)
{
  if (agent_loaded_p ())
    {
      use_agent = use;
      return 1;
    }
  else
    return 0;
}

static int
inf_child_can_use_agent (void)
{
  return agent_loaded_p ();
}

struct target_ops *
inf_child_target (void)
{
  struct target_ops *t = XZALLOC (struct target_ops);

  t->to_shortname = "child";
  t->to_longname = "Unix child process";
  t->to_doc = "Unix child process (started by the \"run\" command).";
  t->to_open = inf_child_open;
  t->to_post_attach = inf_child_post_attach;
  t->to_fetch_registers = inf_child_fetch_inferior_registers;
  t->to_store_registers = inf_child_store_inferior_registers;
  t->to_prepare_to_store = inf_child_prepare_to_store;
  t->to_insert_breakpoint = memory_insert_breakpoint;
  t->to_remove_breakpoint = memory_remove_breakpoint;
  t->to_terminal_init = terminal_init_inferior;
  t->to_terminal_inferior = terminal_inferior;
  t->to_terminal_ours_for_output = terminal_ours_for_output;
  t->to_terminal_save_ours = terminal_save_ours;
  t->to_terminal_ours = terminal_ours;
  t->to_terminal_info = child_terminal_info;
  t->to_post_startup_inferior = inf_child_post_startup_inferior;
  t->to_follow_fork = inf_child_follow_fork;
  t->to_can_run = inf_child_can_run;
  t->to_pid_to_exec_file = inf_child_pid_to_exec_file;
  t->to_stratum = process_stratum;
  t->to_has_all_memory = default_child_has_all_memory;
  t->to_has_memory = default_child_has_memory;
  t->to_has_stack = default_child_has_stack;
  t->to_has_registers = default_child_has_registers;
  t->to_has_execution = default_child_has_execution;
  t->to_fileio_open = inf_child_fileio_open;
  t->to_fileio_pwrite = inf_child_fileio_pwrite;
  t->to_fileio_pread = inf_child_fileio_pread;
  t->to_fileio_close = inf_child_fileio_close;
  t->to_fileio_unlink = inf_child_fileio_unlink;
  t->to_fileio_readlink = inf_child_fileio_readlink;
  t->to_magic = OPS_MAGIC;
  t->to_use_agent = inf_child_use_agent;
  t->to_can_use_agent = inf_child_can_use_agent;
  return t;
}