process.c 239 KB
Newer Older
Jim Blandy's avatar
Jim Blandy committed
1
/* Asynchronous subprocess control for GNU Emacs.
2

Paul Eggert's avatar
Paul Eggert committed
3
Copyright (C) 1985-1988, 1993-1996, 1998-1999, 2001-2017 Free Software
Paul Eggert's avatar
Paul Eggert committed
4
Foundation, Inc.
Jim Blandy's avatar
Jim Blandy committed
5 6 7

This file is part of GNU Emacs.

8
GNU Emacs is free software: you can redistribute it and/or modify
Jim Blandy's avatar
Jim Blandy committed
9
it under the terms of the GNU General Public License as published by
10 11
the Free Software Foundation, either version 3 of the License, or (at
your option) any later version.
Jim Blandy's avatar
Jim Blandy committed
12 13 14 15 16 17 18

GNU Emacs 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
19
along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
Jim Blandy's avatar
Jim Blandy committed
20 21


22
#include <config.h>
Paul Eggert's avatar
Paul Eggert committed
23

Jim Blandy's avatar
Jim Blandy committed
24
#include <stdio.h>
Paul Eggert's avatar
Paul Eggert committed
25
#include <stdlib.h>
Jim Blandy's avatar
Jim Blandy committed
26
#include <errno.h>
27
#include <sys/types.h>		/* Some typedefs are used in sys/file.h.  */
Jim Blandy's avatar
Jim Blandy committed
28 29
#include <sys/file.h>
#include <sys/stat.h>
Richard M. Stallman's avatar
Richard M. Stallman committed
30
#include <unistd.h>
31 32
#include <fcntl.h>

33 34
#include "lisp.h"

35 36 37
/* Only MS-DOS does not define `subprocesses'.  */
#ifdef subprocesses

Jim Blandy's avatar
Jim Blandy committed
38 39 40 41
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>
42

Paul Eggert's avatar
Paul Eggert committed
43 44
#ifdef HAVE_SETRLIMIT
# include <sys/resource.h>
45 46 47 48 49

/* If NOFILE_LIMIT.rlim_cur is greater than FD_SETSIZE, then
   NOFILE_LIMIT is the initial limit on the number of open files,
   which should be restored in child processes.  */
static struct rlimit nofile_limit;
Paul Eggert's avatar
Paul Eggert committed
50 51
#endif

52
/* Are local (unix) sockets supported?  */
53
#if defined (HAVE_SYS_UN_H)
54 55 56 57 58 59 60 61
#if !defined (AF_LOCAL) && defined (AF_UNIX)
#define AF_LOCAL AF_UNIX
#endif
#ifdef AF_LOCAL
#define HAVE_LOCAL_SOCKETS
#include <sys/un.h>
#endif
#endif
Jim Blandy's avatar
Jim Blandy committed
62 63

#include <sys/ioctl.h>
Juanma Barranquero's avatar
Juanma Barranquero committed
64
#if defined (HAVE_NET_IF_H)
65 66
#include <net/if.h>
#endif /* HAVE_NET_IF_H */
Jim Blandy's avatar
Jim Blandy committed
67

Juanma Barranquero's avatar
Juanma Barranquero committed
68
#if defined (HAVE_IFADDRS_H)
69 70 71 72
/* Must be after net/if.h */
#include <ifaddrs.h>

/* We only use structs from this header when we use getifaddrs.  */
Juanma Barranquero's avatar
Juanma Barranquero committed
73
#if defined (HAVE_NET_IF_DL_H)
74 75 76 77 78
#include <net/if_dl.h>
#endif

#endif

Jim Blandy's avatar
Jim Blandy committed
79 80 81 82
#ifdef NEED_BSDTTY
#include <bsdtty.h>
#endif

Paul Eggert's avatar
Paul Eggert committed
83 84 85 86 87
#ifdef USG5_4
# include <sys/stream.h>
# include <sys/stropts.h>
#endif

88 89 90 91
#ifdef HAVE_UTIL_H
#include <util.h>
#endif

Dan Nicolaescu's avatar
Dan Nicolaescu committed
92 93 94 95
#ifdef HAVE_PTY_H
#include <pty.h>
#endif

96
#include <c-ctype.h>
97
#include <flexmember.h>
98
#include <sig2str.h>
99
#include <verify.h>
100

101 102
#endif	/* subprocesses */

Jim Blandy's avatar
Jim Blandy committed
103
#include "systime.h"
104
#include "systty.h"
Jim Blandy's avatar
Jim Blandy committed
105 106

#include "window.h"
107
#include "character.h"
108
#include "buffer.h"
Karl Heuer's avatar
Karl Heuer committed
109
#include "coding.h"
Jim Blandy's avatar
Jim Blandy committed
110
#include "process.h"
111
#include "frame.h"
Jim Blandy's avatar
Jim Blandy committed
112
#include "termopts.h"
113
#include "keyboard.h"
Richard M. Stallman's avatar
Richard M. Stallman committed
114
#include "blockinput.h"
Gerd Moellmann's avatar
Gerd Moellmann committed
115
#include "atimer.h"
116 117 118
#include "sysselect.h"
#include "syssignal.h"
#include "syswait.h"
Ted Zlatanov's avatar
Ted Zlatanov committed
119 120 121
#ifdef HAVE_GNUTLS
#include "gnutls.h"
#endif
Jim Blandy's avatar
Jim Blandy committed
122

123 124 125 126
#ifdef HAVE_WINDOW_SYSTEM
#include TERM_HEADER
#endif /* HAVE_WINDOW_SYSTEM */

127
#ifdef HAVE_GLIB
128
#include "xgselect.h"
129 130 131
#ifndef WINDOWSNT
#include <glib.h>
#endif
132
#endif
Dan Nicolaescu's avatar
Dan Nicolaescu committed
133

134 135 136 137 138
#if defined HAVE_GETADDRINFO_A || defined HAVE_GNUTLS
/* This is 0.1s in nanoseconds. */
#define ASYNC_RETRY_NSEC 100000000
#endif

139
#ifdef WINDOWSNT
140
extern int sys_select (int, fd_set *, fd_set *, fd_set *,
141
                       const struct timespec *, const sigset_t *);
142 143
#endif

144
/* Work around GCC 4.3.0 bug with strict overflow checking; see
145
   <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52904>.
146
   This bug appears to be fixed in GCC 5.1, so don't work around it there.  */
147
#if GNUC_PREREQ (4, 3, 0) && ! GNUC_PREREQ (5, 1, 0)
Eli Zaretskii's avatar
Eli Zaretskii committed
148 149 150 151 152 153 154 155 156 157 158 159 160
# pragma GCC diagnostic ignored "-Wstrict-overflow"
#endif

/* True if keyboard input is on hold, zero otherwise.  */

static bool kbd_is_on_hold;

/* Nonzero means don't run process sentinels.  This is used
   when exiting.  */
bool inhibit_sentinels;

#ifdef subprocesses

161 162
#ifndef SOCK_CLOEXEC
# define SOCK_CLOEXEC 0
Paul Eggert's avatar
Paul Eggert committed
163
#endif
164
#ifndef SOCK_NONBLOCK
165
# define SOCK_NONBLOCK 0
166
#endif
Paul Eggert's avatar
Paul Eggert committed
167

168 169 170 171 172 173 174 175 176 177 178 179
/* True if ERRNUM represents an error where the system call would
   block if a blocking variant were used.  */
static bool
would_block (int errnum)
{
#ifdef EWOULDBLOCK
  if (EWOULDBLOCK != EAGAIN && errnum == EWOULDBLOCK)
    return true;
#endif
  return errnum == EAGAIN;
}

Paul Eggert's avatar
Paul Eggert committed
180
#ifndef HAVE_ACCEPT4
181 182 183 184 185 186 187 188 189 190 191

/* Emulate GNU/Linux accept4 and socket well enough for this module.  */

static int
close_on_exec (int fd)
{
  if (0 <= fd)
    fcntl (fd, F_SETFD, FD_CLOEXEC);
  return fd;
}

192 193 194
# undef accept4
# define accept4(sockfd, addr, addrlen, flags) \
    process_accept4 (sockfd, addr, addrlen, flags)
195 196 197 198 199 200 201 202 203 204 205 206 207 208 209
static int
accept4 (int sockfd, struct sockaddr *addr, socklen_t *addrlen, int flags)
{
  return close_on_exec (accept (sockfd, addr, addrlen));
}

static int
process_socket (int domain, int type, int protocol)
{
  return close_on_exec (socket (domain, type, protocol));
}
# undef socket
# define socket(domain, type, protocol) process_socket (domain, type, protocol)
#endif

210 211 212 213
#define NETCONN_P(p) (EQ (XPROCESS (p)->type, Qnetwork))
#define NETCONN1_P(p) (EQ (p->type, Qnetwork))
#define SERIALCONN_P(p) (EQ (XPROCESS (p)->type, Qserial))
#define SERIALCONN1_P(p) (EQ (p->type, Qserial))
214 215
#define PIPECONN_P(p) (EQ (XPROCESS (p)->type, Qpipe))
#define PIPECONN1_P(p) (EQ (p->type, Qpipe))
Jim Blandy's avatar
Jim Blandy committed
216 217

/* Number of events of change of status of a process.  */
218
static EMACS_INT process_tick;
Jim Blandy's avatar
Jim Blandy committed
219
/* Number of events for which the user or sentinel has been notified.  */
220
static EMACS_INT update_tick;
Jim Blandy's avatar
Jim Blandy committed
221

222 223 224 225 226
/* Define DATAGRAM_SOCKETS if datagrams can be used safely on
   this system.  We need to read full packets, so we need a
   "non-destructive" select.  So we require either native select,
   or emulation of select using FIONREAD.  */

Paul Eggert's avatar
Paul Eggert committed
227 228 229 230 231 232 233
#ifndef BROKEN_DATAGRAM_SOCKETS
# if defined HAVE_SELECT || defined USABLE_FIONREAD
#  if defined HAVE_SENDTO && defined HAVE_RECVFROM && defined EMSGSIZE
#   define DATAGRAM_SOCKETS
#  endif
# endif
#endif
234

Stefan Monnier's avatar
Stefan Monnier committed
235 236 237 238
#if defined HAVE_LOCAL_SOCKETS && defined DATAGRAM_SOCKETS
# define HAVE_SEQPACKET
#endif

239
#define READ_OUTPUT_DELAY_INCREMENT (TIMESPEC_RESOLUTION / 100)
Kenichi Handa's avatar
Kenichi Handa committed
240 241 242
#define READ_OUTPUT_DELAY_MAX       (READ_OUTPUT_DELAY_INCREMENT * 5)
#define READ_OUTPUT_DELAY_MAX_MAX   (READ_OUTPUT_DELAY_INCREMENT * 7)

243 244
/* Number of processes which have a non-zero read_output_delay,
   and therefore might be delayed for adaptive read buffering.  */
Kenichi Handa's avatar
Kenichi Handa committed
245 246 247

static int process_output_delay_count;

248
/* True if any process has non-nil read_output_skip.  */
Kenichi Handa's avatar
Kenichi Handa committed
249

250
static bool process_output_skip;
Kenichi Handa's avatar
Kenichi Handa committed
251

252
static void start_process_unwind (Lisp_Object);
253
static void create_process (Lisp_Object, char **, Lisp_Object);
Paul Eggert's avatar
Paul Eggert committed
254
#ifdef USABLE_SIGIO
255
static bool keyboard_bit_set (fd_set *);
256
#endif
257
static void deactivate_process (Lisp_Object);
258
static int status_notify (struct Lisp_Process *, struct Lisp_Process *);
259 260
static int read_process_output (Lisp_Object, int);
static void create_pty (Lisp_Object);
261
static void exec_sentinel (Lisp_Object, Lisp_Object);
262

263 264
/* Number of bits set in connect_wait_mask.  */
static int num_pending_connects;
265

Tom Tromey's avatar
Tom Tromey committed
266
/* The largest descriptor currently in use; -1 if none.  */
Tom Tromey's avatar
Tom Tromey committed
267
static int max_desc;
268

269 270 271 272
/* Set the external socket descriptor for Emacs to use when
   `make-network-process' is called with a non-nil
   `:use-external-socket' option.  The value should be either -1, or
   the file descriptor of a socket that is already bound.  */
273
static int external_sock_fd;
274

275
/* Indexed by descriptor, gives the process (if any) for that descriptor.  */
276
static Lisp_Object chan_process[FD_SETSIZE];
277
static void wait_for_socket_fds (Lisp_Object, char const *);
Jim Blandy's avatar
Jim Blandy committed
278

279
/* Alist of elements (NAME . PROCESS).  */
280
static Lisp_Object Vprocess_alist;
Jim Blandy's avatar
Jim Blandy committed
281 282 283 284 285 286 287

/* Buffered-ahead input char from process, indexed by channel.
   -1 means empty (no char is buffered).
   Used on sys V where the only way to tell if there is any
   output from the process is to read at least one char.
   Always -1 on systems that support FIONREAD.  */

288
static int proc_buffered_char[FD_SETSIZE];
289

Karl Heuer's avatar
Karl Heuer committed
290
/* Table of `struct coding-system' for each process.  */
291 292
static struct coding_system *proc_decode_coding_system[FD_SETSIZE];
static struct coding_system *proc_encode_coding_system[FD_SETSIZE];
Karl Heuer's avatar
Karl Heuer committed
293

294 295
#ifdef DATAGRAM_SOCKETS
/* Table of `partner address' for datagram sockets.  */
296
static struct sockaddr_and_len {
297
  struct sockaddr *sa;
298
  ptrdiff_t len;
299
} datagram_address[FD_SETSIZE];
300
#define DATAGRAM_CHAN_P(chan)	(datagram_address[chan].sa != 0)
301 302 303 304
#define DATAGRAM_CONN_P(proc)                                           \
  (PROCESSP (proc) &&                                                   \
   XPROCESS (proc)->infd >= 0 &&                                        \
   datagram_address[XPROCESS (proc)->infd].sa != 0)
305 306 307 308
#else
#define DATAGRAM_CONN_P(proc)	(0)
#endif

309 310 311 312 313 314
/* FOR_EACH_PROCESS (LIST_VAR, PROC_VAR) followed by a statement is
   a `for' loop which iterates over processes from Vprocess_alist.  */

#define FOR_EACH_PROCESS(list_var, proc_var)			\
  FOR_EACH_ALIST_VALUE (Vprocess_alist, list_var, proc_var)

Paul Eggert's avatar
Paul Eggert committed
315
/* These setters are used only in this file, so they can be private.  */
316
static void
Paul Eggert's avatar
Paul Eggert committed
317 318 319 320
pset_buffer (struct Lisp_Process *p, Lisp_Object val)
{
  p->buffer = val;
}
321
static void
Paul Eggert's avatar
Paul Eggert committed
322 323 324 325
pset_command (struct Lisp_Process *p, Lisp_Object val)
{
  p->command = val;
}
326
static void
Paul Eggert's avatar
Paul Eggert committed
327 328 329 330
pset_decode_coding_system (struct Lisp_Process *p, Lisp_Object val)
{
  p->decode_coding_system = val;
}
331
static void
Paul Eggert's avatar
Paul Eggert committed
332 333 334 335
pset_decoding_buf (struct Lisp_Process *p, Lisp_Object val)
{
  p->decoding_buf = val;
}
336
static void
Paul Eggert's avatar
Paul Eggert committed
337 338 339 340
pset_encode_coding_system (struct Lisp_Process *p, Lisp_Object val)
{
  p->encode_coding_system = val;
}
341
static void
Paul Eggert's avatar
Paul Eggert committed
342 343 344 345
pset_encoding_buf (struct Lisp_Process *p, Lisp_Object val)
{
  p->encoding_buf = val;
}
346
static void
Paul Eggert's avatar
Paul Eggert committed
347 348
pset_filter (struct Lisp_Process *p, Lisp_Object val)
{
349
  p->filter = NILP (val) ? Qinternal_default_process_filter : val;
Paul Eggert's avatar
Paul Eggert committed
350
}
351
static void
Paul Eggert's avatar
Paul Eggert committed
352 353 354 355
pset_log (struct Lisp_Process *p, Lisp_Object val)
{
  p->log = val;
}
356
static void
Paul Eggert's avatar
Paul Eggert committed
357 358 359 360
pset_mark (struct Lisp_Process *p, Lisp_Object val)
{
  p->mark = val;
}
361
static void
Tom Tromey's avatar
Tom Tromey committed
362 363 364 365
pset_thread (struct Lisp_Process *p, Lisp_Object val)
{
  p->thread = val;
}
Tom Tromey's avatar
Tom Tromey committed
366
static void
Paul Eggert's avatar
Paul Eggert committed
367 368 369 370
pset_name (struct Lisp_Process *p, Lisp_Object val)
{
  p->name = val;
}
371
static void
Paul Eggert's avatar
Paul Eggert committed
372 373 374 375
pset_plist (struct Lisp_Process *p, Lisp_Object val)
{
  p->plist = val;
}
376
static void
Paul Eggert's avatar
Paul Eggert committed
377 378
pset_sentinel (struct Lisp_Process *p, Lisp_Object val)
{
379
  p->sentinel = NILP (val) ? Qinternal_default_process_sentinel : val;
Paul Eggert's avatar
Paul Eggert committed
380
}
381
static void
Paul Eggert's avatar
Paul Eggert committed
382 383 384 385
pset_tty_name (struct Lisp_Process *p, Lisp_Object val)
{
  p->tty_name = val;
}
386
static void
Paul Eggert's avatar
Paul Eggert committed
387 388 389 390
pset_type (struct Lisp_Process *p, Lisp_Object val)
{
  p->type = val;
}
391
static void
Paul Eggert's avatar
Paul Eggert committed
392 393 394 395
pset_write_queue (struct Lisp_Process *p, Lisp_Object val)
{
  p->write_queue = val;
}
396 397 398 399 400
static void
pset_stderrproc (struct Lisp_Process *p, Lisp_Object val)
{
  p->stderrproc = val;
}
Paul Eggert's avatar
Paul Eggert committed
401

402

Dmitry Antipov's avatar
Dmitry Antipov committed
403 404 405 406 407
static Lisp_Object
make_lisp_proc (struct Lisp_Process *p)
{
  return make_lisp_ptr (p, Lisp_Vectorlike);
}
408

409 410 411 412 413 414 415 416 417 418 419 420 421 422 423
enum fd_bits
{
  /* Read from file descriptor.  */
  FOR_READ = 1,
  /* Write to file descriptor.  */
  FOR_WRITE = 2,
  /* This descriptor refers to a keyboard.  Only valid if FOR_READ is
     set.  */
  KEYBOARD_FD = 4,
  /* This descriptor refers to a process.  */
  PROCESS_FD = 8,
  /* A non-blocking connect.  Only valid if FOR_WRITE is set.  */
  NON_BLOCKING_CONNECT_FD = 16
};

424
static struct fd_callback_data
425 426 427
{
  fd_callback func;
  void *data;
428 429
  /* Flags from enum fd_bits.  */
  int flags;
Tom Tromey's avatar
Tom Tromey committed
430 431 432 433 434 435 436
  /* If this fd is locked to a certain thread, this points to it.
     Otherwise, this is NULL.  If an fd is locked to a thread, then
     only that thread is permitted to wait on it.  */
  struct thread_state *thread;
  /* If this fd is currently being selected on by a thread, this
     points to the thread.  Otherwise it is NULL.  */
  struct thread_state *waiting_thread;
437
} fd_callback_info[FD_SETSIZE];
438 439 440 441 442 443 444 445 446 447 448 449


/* Add a file descriptor FD to be monitored for when read is possible.
   When read is possible, call FUNC with argument DATA.  */

void
add_read_fd (int fd, fd_callback func, void *data)
{
  add_keyboard_wait_descriptor (fd);

  fd_callback_info[fd].func = func;
  fd_callback_info[fd].data = data;
450 451
}

Tom Tromey's avatar
Tom Tromey committed
452
static void
453 454
add_non_keyboard_read_fd (int fd)
{
Ken Raeburn's avatar
Ken Raeburn committed
455
  eassert (fd >= 0 && fd < FD_SETSIZE);
456
  eassert (fd_callback_info[fd].func == NULL);
Eli Zaretskii's avatar
Eli Zaretskii committed
457 458

  fd_callback_info[fd].flags &= ~KEYBOARD_FD;
459
  fd_callback_info[fd].flags |= FOR_READ;
Tom Tromey's avatar
Tom Tromey committed
460 461
  if (fd > max_desc)
    max_desc = fd;
462 463
}

Tom Tromey's avatar
Tom Tromey committed
464
static void
465 466 467 468
add_process_read_fd (int fd)
{
  add_non_keyboard_read_fd (fd);
  fd_callback_info[fd].flags |= PROCESS_FD;
469 470 471 472 473 474 475 476 477
}

/* Stop monitoring file descriptor FD for when read is possible.  */

void
delete_read_fd (int fd)
{
  delete_keyboard_wait_descriptor (fd);

478
  if (fd_callback_info[fd].flags == 0)
479 480 481 482 483 484 485 486 487 488 489 490
    {
      fd_callback_info[fd].func = 0;
      fd_callback_info[fd].data = 0;
    }
}

/* Add a file descriptor FD to be monitored for when write is possible.
   When write is possible, call FUNC with argument DATA.  */

void
add_write_fd (int fd, fd_callback func, void *data)
{
Eli Zaretskii's avatar
Eli Zaretskii committed
491
  eassert (fd >= 0 && fd < FD_SETSIZE);
492 493 494

  fd_callback_info[fd].func = func;
  fd_callback_info[fd].data = data;
495
  fd_callback_info[fd].flags |= FOR_WRITE;
Eli Zaretskii's avatar
Eli Zaretskii committed
496 497
  if (fd > max_desc)
    max_desc = fd;
498 499
}

Tom Tromey's avatar
Tom Tromey committed
500
static void
501 502
add_non_blocking_write_fd (int fd)
{
Ken Raeburn's avatar
Ken Raeburn committed
503
  eassert (fd >= 0 && fd < FD_SETSIZE);
504 505 506
  eassert (fd_callback_info[fd].func == NULL);

  fd_callback_info[fd].flags |= FOR_WRITE | NON_BLOCKING_CONNECT_FD;
Tom Tromey's avatar
Tom Tromey committed
507 508
  if (fd > max_desc)
    max_desc = fd;
509
  ++num_pending_connects;
510
}
511 512

static void
Tom Tromey's avatar
Tom Tromey committed
513
recompute_max_desc (void)
514
{
Tom Tromey's avatar
Tom Tromey committed
515
  int fd;
516

Tom Tromey's avatar
Tom Tromey committed
517 518 519 520 521 522 523
  for (fd = max_desc; fd >= 0; --fd)
    {
      if (fd_callback_info[fd].flags != 0)
	{
	  max_desc = fd;
	  break;
	}
524 525 526
    }
}

527 528 529 530 531
/* Stop monitoring file descriptor FD for when write is possible.  */

void
delete_write_fd (int fd)
{
532 533 534
  if ((fd_callback_info[fd].flags & NON_BLOCKING_CONNECT_FD) != 0)
    {
      if (--num_pending_connects < 0)
Eli Zaretskii's avatar
Eli Zaretskii committed
535
	emacs_abort ();
536 537 538
    }
  fd_callback_info[fd].flags &= ~(FOR_WRITE | NON_BLOCKING_CONNECT_FD);
  if (fd_callback_info[fd].flags == 0)
539 540 541 542
    {
      fd_callback_info[fd].func = 0;
      fd_callback_info[fd].data = 0;

Tom Tromey's avatar
Tom Tromey committed
543 544
      if (fd == max_desc)
	recompute_max_desc ();
545 546 547 548
    }
}

static void
Ken Raeburn's avatar
Ken Raeburn committed
549
compute_input_wait_mask (fd_set *mask)
550 551
{
  int fd;
552

553
  FD_ZERO (mask);
Tom Tromey's avatar
Tom Tromey committed
554
  for (fd = 0; fd <= max_desc; ++fd)
555
    {
Tom Tromey's avatar
Tom Tromey committed
556 557 558 559 560 561
      if (fd_callback_info[fd].thread != NULL
	  && fd_callback_info[fd].thread != current_thread)
	continue;
      if (fd_callback_info[fd].waiting_thread != NULL
	  && fd_callback_info[fd].waiting_thread != current_thread)
	continue;
562
      if ((fd_callback_info[fd].flags & FOR_READ) != 0)
Tom Tromey's avatar
Tom Tromey committed
563 564 565 566
	{
	  FD_SET (fd, mask);
	  fd_callback_info[fd].waiting_thread = current_thread;
	}
567 568 569
    }
}

570
static void
Ken Raeburn's avatar
Ken Raeburn committed
571
compute_non_process_wait_mask (fd_set *mask)
572 573 574 575
{
  int fd;

  FD_ZERO (mask);
Tom Tromey's avatar
Tom Tromey committed
576
  for (fd = 0; fd <= max_desc; ++fd)
577
    {
Tom Tromey's avatar
Tom Tromey committed
578 579 580 581 582 583
      if (fd_callback_info[fd].thread != NULL
	  && fd_callback_info[fd].thread != current_thread)
	continue;
      if (fd_callback_info[fd].waiting_thread != NULL
	  && fd_callback_info[fd].waiting_thread != current_thread)
	continue;
584 585
      if ((fd_callback_info[fd].flags & FOR_READ) != 0
	  && (fd_callback_info[fd].flags & PROCESS_FD) == 0)
Tom Tromey's avatar
Tom Tromey committed
586 587 588 589
	{
	  FD_SET (fd, mask);
	  fd_callback_info[fd].waiting_thread = current_thread;
	}
590 591 592 593
    }
}

static void
Ken Raeburn's avatar
Ken Raeburn committed
594
compute_non_keyboard_wait_mask (fd_set *mask)
595 596 597 598
{
  int fd;

  FD_ZERO (mask);
Tom Tromey's avatar
Tom Tromey committed
599
  for (fd = 0; fd <= max_desc; ++fd)
600
    {
Tom Tromey's avatar
Tom Tromey committed
601 602 603 604 605 606
      if (fd_callback_info[fd].thread != NULL
	  && fd_callback_info[fd].thread != current_thread)
	continue;
      if (fd_callback_info[fd].waiting_thread != NULL
	  && fd_callback_info[fd].waiting_thread != current_thread)
	continue;
607 608
      if ((fd_callback_info[fd].flags & FOR_READ) != 0
	  && (fd_callback_info[fd].flags & KEYBOARD_FD) == 0)
Tom Tromey's avatar
Tom Tromey committed
609 610 611 612
	{
	  FD_SET (fd, mask);
	  fd_callback_info[fd].waiting_thread = current_thread;
	}
613 614 615 616
    }
}

static void
Ken Raeburn's avatar
Ken Raeburn committed
617
compute_write_mask (fd_set *mask)
618 619 620 621
{
  int fd;

  FD_ZERO (mask);
Tom Tromey's avatar
Tom Tromey committed
622
  for (fd = 0; fd <= max_desc; ++fd)
623
    {
Tom Tromey's avatar
Tom Tromey committed
624 625 626 627 628 629
      if (fd_callback_info[fd].thread != NULL
	  && fd_callback_info[fd].thread != current_thread)
	continue;
      if (fd_callback_info[fd].waiting_thread != NULL
	  && fd_callback_info[fd].waiting_thread != current_thread)
	continue;
630
      if ((fd_callback_info[fd].flags & FOR_WRITE) != 0)
Tom Tromey's avatar
Tom Tromey committed
631 632 633 634
	{
	  FD_SET (fd, mask);
	  fd_callback_info[fd].waiting_thread = current_thread;
	}
635 636 637
    }
}

Tom Tromey's avatar
Tom Tromey committed
638 639 640 641
static void
clear_waiting_thread_info (void)
{
  int fd;
642

Tom Tromey's avatar
Tom Tromey committed
643
  for (fd = 0; fd <= max_desc; ++fd)
Tom Tromey's avatar
Tom Tromey committed
644 645 646
    {
      if (fd_callback_info[fd].waiting_thread == current_thread)
	fd_callback_info[fd].waiting_thread = NULL;
647 648 649
    }
}

Jim Blandy's avatar
Jim Blandy committed
650 651 652 653

/* Compute the Lisp form of the process status, p->status, from
   the numeric status that was returned by `wait'.  */

654
static Lisp_Object status_convert (int);
655

656
static void
657
update_status (struct Lisp_Process *p)
Jim Blandy's avatar
Jim Blandy committed
658
{
659
  eassert (p->raw_status_new);
Paul Eggert's avatar
Paul Eggert committed
660
  pset_status (p, status_convert (p->raw_status));
661
  p->raw_status_new = 0;
Jim Blandy's avatar
Jim Blandy committed
662 663
}

664
/*  Convert a process status word in Unix format to
Jim Blandy's avatar
Jim Blandy committed
665 666
    the list that we use internally.  */

667
static Lisp_Object
668
status_convert (int w)
Jim Blandy's avatar
Jim Blandy committed
669 670 671 672
{
  if (WIFSTOPPED (w))
    return Fcons (Qstop, Fcons (make_number (WSTOPSIG (w)), Qnil));
  else if (WIFEXITED (w))
Paul Eggert's avatar
Paul Eggert committed
673
    return Fcons (Qexit, Fcons (make_number (WEXITSTATUS (w)),
Jim Blandy's avatar
Jim Blandy committed
674 675 676 677 678 679 680 681
				WCOREDUMP (w) ? Qt : Qnil));
  else if (WIFSIGNALED (w))
    return Fcons (Qsignal, Fcons (make_number (WTERMSIG (w)),
				  WCOREDUMP (w) ? Qt : Qnil));
  else
    return Qrun;
}

682 683 684 685 686 687 688 689
/* True if STATUS is that of a process attempting connection.  */

static bool
connecting_status (Lisp_Object status)
{
  return CONSP (status) && EQ (XCAR (status), Qconnect);
}

Jim Blandy's avatar
Jim Blandy committed
690 691 692
/* Given a status-list, extract the three pieces of information
   and store them individually through the three pointers.  */

693
static void
694 695
decode_status (Lisp_Object l, Lisp_Object *symbol, Lisp_Object *code,
	       bool *coredump)
Jim Blandy's avatar
Jim Blandy committed
696 697 698
{
  Lisp_Object tem;

699 700 701
  if (connecting_status (l))
    l = XCAR (l);

702
  if (SYMBOLP (l))
Jim Blandy's avatar
Jim Blandy committed
703 704
    {
      *symbol = l;
705
      *code = make_number (0);
Jim Blandy's avatar
Jim Blandy committed
706 707 708 709
      *coredump = 0;
    }
  else
    {
710 711
      *symbol = XCAR (l);
      tem = XCDR (l);
712
      *code = XCAR (tem);
713
      tem = XCDR (tem);
Jim Blandy's avatar
Jim Blandy committed
714 715 716 717 718 719
      *coredump = !NILP (tem);
    }
}

/* Return a string describing a process status list.  */

720
static Lisp_Object
721
status_message (struct Lisp_Process *p)
Jim Blandy's avatar
Jim Blandy committed
722
{
723
  Lisp_Object status = p->status;
724
  Lisp_Object symbol, code;
725
  bool coredump;
726
  Lisp_Object string;
Jim Blandy's avatar
Jim Blandy committed
727 728 729 730 731

  decode_status (status, &symbol, &code, &coredump);

  if (EQ (symbol, Qsignal) || EQ (symbol, Qstop))
    {
732
      char const *signame;
733
      synchronize_system_messages_locale ();
734
      signame = strsignal (XFASTINT (code));
735
      if (signame == 0)
736 737 738 739 740
	string = build_string ("unknown");
      else
	{
	  int c1, c2;

741
	  string = build_unibyte_string (signame);
742 743 744
	  if (! NILP (Vlocale_coding_system))
	    string = (code_convert_string_norecord
		      (string, Vlocale_coding_system, 0));
745
	  c1 = STRING_CHAR (SDATA (string));
746
	  c2 = downcase (c1);
747
	  if (c1 != c2)
748
	    Faset (string, make_number (0), make_number (c2));
749
	}
750 751
      AUTO_STRING (suffix, coredump ? " (core dumped)\n" : "\n");
      return concat2 (string, suffix);
Jim Blandy's avatar
Jim Blandy committed
752 753 754
    }
  else if (EQ (symbol, Qexit))
    {
755
      if (NETCONN1_P (p))
756 757 758 759
	return build_string (XFASTINT (code) == 0
			     ? "deleted\n"
			     : "connection broken by remote peer\n");
      if (XFASTINT (code) == 0)
Jim Blandy's avatar
Jim Blandy committed
760
	return build_string ("finished\n");
761
      AUTO_STRING (prefix, "exited abnormally with code ");
762
      string = Fnumber_to_string (code);
763 764
      AUTO_STRING (suffix, coredump ? " (core dumped)\n" : "\n");
      return concat3 (prefix, string, suffix);
Jim Blandy's avatar
Jim Blandy committed
765
    }
766 767
  else if (EQ (symbol, Qfailed))
    {
768 769
      AUTO_STRING (format, "failed with code %s\n");
      return CALLN (Fformat, format, code);
770
    }
Jim Blandy's avatar
Jim Blandy committed
771 772 773 774
  else
    return Fcopy_sequence (Fsymbol_name (symbol));
}

775
enum { PTY_NAME_SIZE = 24 };
Dan Nicolaescu's avatar
Dan Nicolaescu committed
776

777
/* Open an available pty, returning a file descriptor.
778 779
   Store into PTY_NAME the file name of the terminal corresponding to the pty.
   Return -1 on failure.  */
780

781
static int
782
allocate_pty (char pty_name[PTY_NAME_SIZE])
Jim Blandy's avatar
Jim Blandy committed
783
{
784
#ifdef HAVE_PTYS
Jim Blandy's avatar
Jim Blandy committed
785 786 787 788 789
  int fd;

#ifdef PTY_ITERATION
  PTY_ITERATION
#else
790
  register int c, i;
Jim Blandy's avatar
Jim Blandy committed
791 792 793 794 795 796 797 798 799 800
  for (c = FIRST_PTY_LETTER; c <= 'z'; c++)
    for (i = 0; i < 16; i++)
#endif
      {
#ifdef PTY_NAME_SPRINTF
	PTY_NAME_SPRINTF
#else
	sprintf (pty_name, "/dev/pty%c%x", c, i);
#endif /* no PTY_NAME_SPRINTF */

801 802 803
#ifdef PTY_OPEN
	PTY_OPEN;
#else /* no PTY_OPEN */
804
	fd = emacs_open (pty_name, O_RDWR | O_NONBLOCK, 0);
805
#endif /* no PTY_OPEN */
Jim Blandy's avatar
Jim Blandy committed
806 807 808

	if (fd >= 0)
	  {
809 810 811 812 813 814
#ifdef PTY_TTY_NAME_SPRINTF
	    PTY_TTY_NAME_SPRINTF
#else
	    sprintf (pty_name, "/dev/tty%c%x", c, i);
#endif /* no PTY_TTY_NAME_SPRINTF */

815 816 817
	    /* Set FD's close-on-exec flag.  This is needed even if
	       PT_OPEN calls posix_openpt with O_CLOEXEC, since POSIX
	       doesn't require support for that combination.
818 819
	       Do this after PTY_TTY_NAME_SPRINTF, which on some platforms
	       doesn't work if the close-on-exec flag is set (Bug#20555).
820 821 822 823
	       Multithreaded platforms where posix_openpt ignores
	       O_CLOEXEC (or where PTY_OPEN doesn't call posix_openpt)
	       have a race condition between the PTY_OPEN and here.  */
	    fcntl (fd, F_SETFD, FD_CLOEXEC);
824 825 826

	    /* Check to make certain that both sides are available.
	       This avoids a nasty yet stupid bug in rlogins.  */
827
	    if (faccessat (AT_FDCWD, pty_name, R_OK | W_OK, AT_EACCESS) != 0)
Jim Blandy's avatar
Jim Blandy committed
828
	      {
829
		emacs_close (fd);
Jim Blandy's avatar
Jim Blandy committed
830 831 832 833 834 835
		continue;
	      }
	    setup_pty (fd);
	    return fd;
	  }
      }
836
#endif /* HAVE_PTYS */
Jim Blandy's avatar
Jim Blandy committed
837 838
  return -1;
}
839 840 841 842 843 844 845 846 847

/* Allocate basically initialized process.  */

static struct Lisp_Process *
allocate_process (void)
{
  return ALLOCATE_ZEROED_PSEUDOVECTOR (struct Lisp_Process, pid, PVEC_PROCESS);
}

848
static Lisp_Object
849
make_process (Lisp_Object name)
Jim Blandy's avatar
Jim Blandy committed
850
{
851
  struct Lisp_Process *p = allocate_process ();
852 853
  /* Initialize Lisp data.  Note that allocate_process initializes all
     Lisp data to nil, so do it only for slots which should not be nil.  */
Paul Eggert's avatar
Paul Eggert committed
854 855
  pset_status (p, Qrun);
  pset_mark (p, Fmake_marker ());
Tom Tromey's avatar
Tom Tromey committed
856
  pset_thread (p, Fcurrent_thread ());
Jim Blandy's avatar
Jim Blandy committed
857

858 859 860 861
  /* Initialize non-Lisp data.  Note that allocate_process zeroes out all
     non-Lisp data, so do it only for slots which should not be zero.  */
  p->infd = -1;
  p->outfd = -1;
862
  for (int i = 0; i < PROCESS_OPEN_FDS; i++)
863
    p->open_fd[i] = -1;
Kenichi Handa's avatar
Kenichi Handa committed
864

Ted Zlatanov's avatar
Ted Zlatanov committed
865
#ifdef HAVE_GNUTLS
866 867 868
  verify (GNUTLS_STAGE_EMPTY == 0);
  eassert (p->gnutls_initstage == GNUTLS_STAGE_EMPTY);
  eassert (NILP (p->gnutls_boot_parameters));
Ted Zlatanov's avatar
Ted Zlatanov committed
869 870
#endif

Jim Blandy's avatar
Jim Blandy committed
871 872
  /* If name is already in use, modify it until it is unused.  */

873 874
  Lisp_Object name1 = name;
  for (printmax_t i = 1; ; i++)
Jim Blandy's avatar
Jim Blandy committed
875
    {
876 877 878 879 880 881 882
      Lisp_Object tem = Fget_process (name1);
      if (NILP (tem))
	break;
      char const suffix_fmt[] = "<%"pMd">";
      char suffix[sizeof suffix_fmt + INT_STRLEN_BOUND (printmax_t)];
      AUTO_STRING_WITH_LEN (lsuffix, suffix, sprintf (suffix, suffix_fmt, i));
      name1 = concat2 (name, lsuffix);
Jim Blandy's avatar
Jim Blandy committed
883 884
    }
  name = name1;
Paul Eggert's avatar
Paul Eggert committed
885
  pset_name (p, name);
886 887
  pset_sentinel (p, Qinternal_default_process_sentinel);
  pset_filter (p, Qinternal_default_process_filter);
888
  Lisp_Object val;
889
  XSETPROCESS (val, p);
Jim Blandy's avatar
Jim Blandy committed
890 891 892 893
  Vprocess_alist = Fcons (Fcons (name, val), Vprocess_alist);
  return val;
}

894
static void
895
remove_process (register Lisp_Object proc)
Jim Blandy's avatar
Jim Blandy committed
896 897 898 899 900 901 902 903
{
  register Lisp_Object pair;

  pair = Frassq (proc, Vprocess_alist);
  Vprocess_alist = Fdelq (pair, Vprocess_alist);

  deactivate_process (proc);
}
904

Tom Tromey's avatar
Tom Tromey committed
905 906 907 908 909 910 911 912 913 914 915 916
void
update_processes_for_thread_death (Lisp_Object dying_thread)
{
  Lisp_Object pair;

  for (pair = Vprocess_alist; !NILP (pair); pair = XCDR (pair))
    {
      Lisp_Object process = XCDR (XCAR (pair));
      if (EQ (XPROCESS (process)->thread, dying_thread))
	{
	  struct Lisp_Process *proc = XPROCESS (process);

Eli Zaretskii's avatar
Eli Zaretskii committed
917
	  pset_thread (proc, Qnil);
Tom Tromey's avatar
Tom Tromey committed
918 919 920 921 922 923 924 925
	  if (proc->infd >= 0)
	    fd_callback_info[proc->infd].thread = NULL;
	  if (proc->outfd >= 0)
	    fd_callback_info[proc->outfd].thread = NULL;
	}
    }
}

926 927 928 929 930 931
#ifdef HAVE_GETADDRINFO_A
static void
free_dns_request (Lisp_Object proc)
{
  struct Lisp_Process *p = XPROCESS (proc);

932 933 934 935
  if (p->dns_request->ar_result)
    freeaddrinfo (p->dns_request->ar_result);
  xfree (p->dns_request);
  p->dns_request = NULL;
936 937 938
}
#endif

Jim Blandy's avatar
Jim Blandy committed
939 940

DEFUN ("processp", Fprocessp, Sprocessp, 1, 1, 0,
941
       doc: /* Return t if OBJECT is a process.  */)
Dan Nicolaescu's avatar
Dan Nicolaescu committed
942
  (Lisp_Object object)
Jim Blandy's avatar
Jim Blandy committed
943
{
944
  return PROCESSP (object) ? Qt : Qnil;
Jim Blandy's avatar
Jim Blandy committed
945 946 947
}

DEFUN ("get-process", Fget_process, Sget_process, 1, 1, 0,
948
       doc: /* Return the process named NAME, or nil if there is none.  */)
Dan Nicolaescu's avatar
Dan Nicolaescu committed
949
  (register Lisp_Object name)
Jim Blandy's avatar
Jim Blandy committed
950
{
951
  if (PROCESSP (name))
Jim Blandy's avatar
Jim Blandy committed
952
    return name;
953
  CHECK_STRING (name);
954
  return Fcdr (Fassoc (name, Vprocess_alist, Qnil));
Jim Blandy's avatar
Jim Blandy committed
955 956
}

Jim Blandy's avatar
Jim Blandy committed
957 958 959 960
/* This is how commands for the user decode process arguments.  It
   accepts a process, a process name, a buffer, a buffer name, or nil.
   Buffers denote the first process in the buffer, and nil denotes the
   current buffer.  */
Jim Blandy's avatar
Jim Blandy committed
961

962
static Lisp_Object
963
get_process (register Lisp_Object name)
Jim Blandy's avatar
Jim Blandy committed
964
{
965 966 967 968 969 970 971
  register Lisp_Object proc, obj;
  if (STRINGP (name))
    {
      obj = Fget_process (name);
      if (NILP (obj))
	obj = Fget_buffer (name);
      if (NILP (obj))
972
	error ("Process %s does not exist", SDATA (name));
973 974 975
    }
  else if (NILP (name))
    obj = Fcurrent_buffer ();
Jim Blandy's avatar
Jim Blandy committed
976
  else
977 978
    obj = name;

979 980
  /* Now obj should be either a buffer object or a process object.  */
  if (BUFFERP (obj))
Jim Blandy's avatar
Jim Blandy committed
981
    {
982 983
      if (NILP (BVAR (XBUFFER (obj), name)))
        error ("Attempt to get process for a dead buffer");
984
      proc = Fget_buffer_process (obj);
Jim Blandy's avatar
Jim Blandy committed
985
      if (NILP (proc))
986
        error ("Buffer %s has no process", SDATA (BVAR (XBUFFER (obj), name)));
Jim Blandy's avatar
Jim Blandy committed
987 988
    }
  else
989
    {
990
      CHECK_PROCESS (obj);
991 992 993
      proc = obj;
    }
  return proc;
Jim Blandy's avatar
Jim Blandy committed
994 995
}

996 997 998

/* Fdelete_process promises to immediately forget about the process, but in
   reality, Emacs needs to remember those processes until they have been
999
   treated by the SIGCHLD handler and waitpid has been invoked on them;
1000 1001
   otherwise they might fill up the kernel's process table.

1002 1003 1004 1005 1006
   Some processes created by call-process are also put onto this list.

   Members of this list are (process-ID . filename) pairs.  The
   process-ID is a number; the filename, if a string, is a file that
   needs to be removed after the process exits.  */
1007 1008
static Lisp_Object deleted_pid_list;

1009
void
1010
record_deleted_pid (pid_t pid, Lisp_Object filename)
1011
{
1012
  deleted_pid_list = Fcons (Fcons (make_fixnum_or_float (pid), filename),
1013 1014 1015 1016 1017
			    /* GC treated elements set to nil.  */
			    Fdelq (Qnil, deleted_pid_list));

}

Jim Blandy's avatar
Jim Blandy committed
1018
DEFUN ("delete-process", Fdelete_process, Sdelete_process, 1, 1, 0,
1019 1020 1021
       doc: /* Delete PROCESS: kill it and forget about it immediately.
PROCESS may be a process, a buffer, the name of a process or buffer, or
nil, indicating the current buffer's process.  */)
Dan Nicolaescu's avatar
Dan Nicolaescu committed
1022
  (register Lisp_Object process)
Jim Blandy's avatar
Jim Blandy committed
1023
{
1024 1025
  register struct Lisp_Process *p;

1026
  process = get_process (process);
1027 1028
  p = XPROCESS (process);

1029
#ifdef HAVE_GETADDRINFO_A
1030
  if (p->dns_request)
1031
    {
1032 1033
      /* Cancel the request.  Unless shutting down, wait until
	 completion.  Free the request if completely canceled. */
1034

1035 1036
      bool canceled = gai_cancel (p->dns_request) != EAI_NOTCANCELED;
      if (!canceled && !inhibit_sentinels)
1037
	{
1038 1039 1040 1041
	  struct gaicb const *req = p->dns_request;
	  while (gai_suspend (&req, 1, NULL) != 0)
	    continue;
	  canceled = true;
1042
	}
1043 1044
      if (canceled)
	free_dns_request (process);
1045 1046 1047
    }
#endif

1048
  p->raw_status_new = 0;
1049
  if (NETCONN1_P (p) || SERIALCONN1_P (p) || PIPECONN1_P (p))
Jim Blandy's avatar
Jim Blandy committed
1050