process.c 240 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, 2001-2018 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

Eli Zaretskii's avatar
Eli Zaretskii committed
43 44
#endif	/* subprocesses */

Paul Eggert's avatar
Paul Eggert committed
45 46
#ifdef HAVE_SETRLIMIT
# include <sys/resource.h>
47 48 49 50 51

/* 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
52 53
#endif

Eli Zaretskii's avatar
Eli Zaretskii committed
54 55
#ifdef subprocesses

56
/* Are local (unix) sockets supported?  */
57
#if defined (HAVE_SYS_UN_H)
58 59 60 61 62 63 64 65
#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
66 67

#include <sys/ioctl.h>
Juanma Barranquero's avatar
Juanma Barranquero committed
68
#if defined (HAVE_NET_IF_H)
69 70
#include <net/if.h>
#endif /* HAVE_NET_IF_H */
Jim Blandy's avatar
Jim Blandy committed
71

Juanma Barranquero's avatar
Juanma Barranquero committed
72
#if defined (HAVE_IFADDRS_H)
73 74 75 76
/* 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
77
#if defined (HAVE_NET_IF_DL_H)
78 79 80 81 82
#include <net/if_dl.h>
#endif

#endif

Jim Blandy's avatar
Jim Blandy committed
83 84 85 86
#ifdef NEED_BSDTTY
#include <bsdtty.h>
#endif

Paul Eggert's avatar
Paul Eggert committed
87 88 89 90 91
#ifdef USG5_4
# include <sys/stream.h>
# include <sys/stropts.h>
#endif

92 93 94 95
#ifdef HAVE_UTIL_H
#include <util.h>
#endif

Dan Nicolaescu's avatar
Dan Nicolaescu committed
96 97 98 99
#ifdef HAVE_PTY_H
#include <pty.h>
#endif

100
#include <c-ctype.h>
101
#include <flexmember.h>
102
#include <sig2str.h>
103
#include <verify.h>
104

105 106
#endif	/* subprocesses */

Jim Blandy's avatar
Jim Blandy committed
107
#include "systime.h"
108
#include "systty.h"
Jim Blandy's avatar
Jim Blandy committed
109 110

#include "window.h"
111
#include "character.h"
112
#include "buffer.h"
Karl Heuer's avatar
Karl Heuer committed
113
#include "coding.h"
Jim Blandy's avatar
Jim Blandy committed
114
#include "process.h"
115
#include "frame.h"
Jim Blandy's avatar
Jim Blandy committed
116
#include "termopts.h"
117
#include "keyboard.h"
Richard M. Stallman's avatar
Richard M. Stallman committed
118
#include "blockinput.h"
Gerd Moellmann's avatar
Gerd Moellmann committed
119
#include "atimer.h"
120 121 122
#include "sysselect.h"
#include "syssignal.h"
#include "syswait.h"
Ted Zlatanov's avatar
Ted Zlatanov committed
123 124 125
#ifdef HAVE_GNUTLS
#include "gnutls.h"
#endif
Jim Blandy's avatar
Jim Blandy committed
126

127 128 129 130
#ifdef HAVE_WINDOW_SYSTEM
#include TERM_HEADER
#endif /* HAVE_WINDOW_SYSTEM */

131
#ifdef HAVE_GLIB
132
#include "xgselect.h"
133 134 135
#ifndef WINDOWSNT
#include <glib.h>
#endif
136
#endif
Dan Nicolaescu's avatar
Dan Nicolaescu committed
137

138 139 140 141 142
#if defined HAVE_GETADDRINFO_A || defined HAVE_GNUTLS
/* This is 0.1s in nanoseconds. */
#define ASYNC_RETRY_NSEC 100000000
#endif

143
#ifdef WINDOWSNT
144
extern int sys_select (int, fd_set *, fd_set *, fd_set *,
145
                       const struct timespec *, const sigset_t *);
146 147
#endif

148
/* Work around GCC 4.3.0 bug with strict overflow checking; see
149
   <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52904>.
150
   This bug appears to be fixed in GCC 5.1, so don't work around it there.  */
151
#if GNUC_PREREQ (4, 3, 0) && ! GNUC_PREREQ (5, 1, 0)
Eli Zaretskii's avatar
Eli Zaretskii committed
152 153 154 155 156 157 158 159 160 161 162 163 164
# 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

165 166
#ifndef SOCK_CLOEXEC
# define SOCK_CLOEXEC 0
Paul Eggert's avatar
Paul Eggert committed
167
#endif
168
#ifndef SOCK_NONBLOCK
169
# define SOCK_NONBLOCK 0
170
#endif
Paul Eggert's avatar
Paul Eggert committed
171

172 173 174 175 176 177 178 179 180 181 182 183
/* 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
184
#ifndef HAVE_ACCEPT4
185 186 187 188 189 190 191 192 193 194 195

/* 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;
}

196 197 198
# undef accept4
# define accept4(sockfd, addr, addrlen, flags) \
    process_accept4 (sockfd, addr, addrlen, flags)
199 200 201 202 203 204 205 206 207 208 209 210 211 212 213
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

214 215 216 217
#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))
218 219
#define PIPECONN_P(p) (EQ (XPROCESS (p)->type, Qpipe))
#define PIPECONN1_P(p) (EQ (p->type, Qpipe))
Jim Blandy's avatar
Jim Blandy committed
220 221

/* Number of events of change of status of a process.  */
222
static EMACS_INT process_tick;
Jim Blandy's avatar
Jim Blandy committed
223
/* Number of events for which the user or sentinel has been notified.  */
224
static EMACS_INT update_tick;
Jim Blandy's avatar
Jim Blandy committed
225

226 227 228 229 230
/* 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
231 232 233 234 235 236 237
#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
238

Stefan Monnier's avatar
Stefan Monnier committed
239 240 241 242
#if defined HAVE_LOCAL_SOCKETS && defined DATAGRAM_SOCKETS
# define HAVE_SEQPACKET
#endif

243
#define READ_OUTPUT_DELAY_INCREMENT (TIMESPEC_RESOLUTION / 100)
Kenichi Handa's avatar
Kenichi Handa committed
244 245 246
#define READ_OUTPUT_DELAY_MAX       (READ_OUTPUT_DELAY_INCREMENT * 5)
#define READ_OUTPUT_DELAY_MAX_MAX   (READ_OUTPUT_DELAY_INCREMENT * 7)

247 248
/* 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
249 250 251

static int process_output_delay_count;

252
/* True if any process has non-nil read_output_skip.  */
Kenichi Handa's avatar
Kenichi Handa committed
253

254
static bool process_output_skip;
Kenichi Handa's avatar
Kenichi Handa committed
255

256
static void start_process_unwind (Lisp_Object);
257
static void create_process (Lisp_Object, char **, Lisp_Object);
Paul Eggert's avatar
Paul Eggert committed
258
#ifdef USABLE_SIGIO
259
static bool keyboard_bit_set (fd_set *);
260
#endif
261
static void deactivate_process (Lisp_Object);
262
static int status_notify (struct Lisp_Process *, struct Lisp_Process *);
263 264
static int read_process_output (Lisp_Object, int);
static void create_pty (Lisp_Object);
265
static void exec_sentinel (Lisp_Object, Lisp_Object);
266

267 268
/* Number of bits set in connect_wait_mask.  */
static int num_pending_connects;
269

Tom Tromey's avatar
Tom Tromey committed
270
/* The largest descriptor currently in use; -1 if none.  */
Tom Tromey's avatar
Tom Tromey committed
271
static int max_desc;
272

273 274 275 276
/* 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.  */
277
static int external_sock_fd;
278

279 280 281 282
/* The name (path) of the socket that was passed to Emacs, when
   `external_sock_fd' is not -1.  */
static const char *external_sock_name = NULL;

283
/* Indexed by descriptor, gives the process (if any) for that descriptor.  */
284
static Lisp_Object chan_process[FD_SETSIZE];
285
static void wait_for_socket_fds (Lisp_Object, char const *);
Jim Blandy's avatar
Jim Blandy committed
286

287
/* Alist of elements (NAME . PROCESS).  */
288
static Lisp_Object Vprocess_alist;
Jim Blandy's avatar
Jim Blandy committed
289 290 291 292 293 294 295

/* 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.  */

296
static int proc_buffered_char[FD_SETSIZE];
297

Karl Heuer's avatar
Karl Heuer committed
298
/* Table of `struct coding-system' for each process.  */
299 300
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
301

302 303
#ifdef DATAGRAM_SOCKETS
/* Table of `partner address' for datagram sockets.  */
304
static struct sockaddr_and_len {
305
  struct sockaddr *sa;
306
  ptrdiff_t len;
307
} datagram_address[FD_SETSIZE];
308
#define DATAGRAM_CHAN_P(chan)	(datagram_address[chan].sa != 0)
309 310 311 312
#define DATAGRAM_CONN_P(proc)                                           \
  (PROCESSP (proc) &&                                                   \
   XPROCESS (proc)->infd >= 0 &&                                        \
   datagram_address[XPROCESS (proc)->infd].sa != 0)
313 314 315 316
#else
#define DATAGRAM_CONN_P(proc)	(0)
#endif

317 318 319 320 321 322
/* 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
323
/* These setters are used only in this file, so they can be private.  */
324
static void
Paul Eggert's avatar
Paul Eggert committed
325 326 327 328
pset_buffer (struct Lisp_Process *p, Lisp_Object val)
{
  p->buffer = val;
}
329
static void
Paul Eggert's avatar
Paul Eggert committed
330 331 332 333
pset_command (struct Lisp_Process *p, Lisp_Object val)
{
  p->command = val;
}
334
static void
Paul Eggert's avatar
Paul Eggert committed
335 336 337 338
pset_decode_coding_system (struct Lisp_Process *p, Lisp_Object val)
{
  p->decode_coding_system = val;
}
339
static void
Paul Eggert's avatar
Paul Eggert committed
340 341 342 343
pset_decoding_buf (struct Lisp_Process *p, Lisp_Object val)
{
  p->decoding_buf = val;
}
344
static void
Paul Eggert's avatar
Paul Eggert committed
345 346 347 348
pset_encode_coding_system (struct Lisp_Process *p, Lisp_Object val)
{
  p->encode_coding_system = val;
}
349
static void
Paul Eggert's avatar
Paul Eggert committed
350 351 352 353
pset_encoding_buf (struct Lisp_Process *p, Lisp_Object val)
{
  p->encoding_buf = val;
}
354
static void
Paul Eggert's avatar
Paul Eggert committed
355 356
pset_filter (struct Lisp_Process *p, Lisp_Object val)
{
357
  p->filter = NILP (val) ? Qinternal_default_process_filter : val;
Paul Eggert's avatar
Paul Eggert committed
358
}
359
static void
Paul Eggert's avatar
Paul Eggert committed
360 361 362 363
pset_log (struct Lisp_Process *p, Lisp_Object val)
{
  p->log = val;
}
364
static void
Paul Eggert's avatar
Paul Eggert committed
365 366 367 368
pset_mark (struct Lisp_Process *p, Lisp_Object val)
{
  p->mark = val;
}
369
static void
Tom Tromey's avatar
Tom Tromey committed
370 371 372 373
pset_thread (struct Lisp_Process *p, Lisp_Object val)
{
  p->thread = val;
}
Tom Tromey's avatar
Tom Tromey committed
374
static void
Paul Eggert's avatar
Paul Eggert committed
375 376 377 378
pset_name (struct Lisp_Process *p, Lisp_Object val)
{
  p->name = val;
}
379
static void
Paul Eggert's avatar
Paul Eggert committed
380 381 382 383
pset_plist (struct Lisp_Process *p, Lisp_Object val)
{
  p->plist = val;
}
384
static void
Paul Eggert's avatar
Paul Eggert committed
385 386
pset_sentinel (struct Lisp_Process *p, Lisp_Object val)
{
387
  p->sentinel = NILP (val) ? Qinternal_default_process_sentinel : val;
Paul Eggert's avatar
Paul Eggert committed
388
}
389
static void
Paul Eggert's avatar
Paul Eggert committed
390 391 392 393
pset_tty_name (struct Lisp_Process *p, Lisp_Object val)
{
  p->tty_name = val;
}
394
static void
Paul Eggert's avatar
Paul Eggert committed
395 396 397 398
pset_type (struct Lisp_Process *p, Lisp_Object val)
{
  p->type = val;
}
399
static void
Paul Eggert's avatar
Paul Eggert committed
400 401 402 403
pset_write_queue (struct Lisp_Process *p, Lisp_Object val)
{
  p->write_queue = val;
}
404 405 406 407 408
static void
pset_stderrproc (struct Lisp_Process *p, Lisp_Object val)
{
  p->stderrproc = val;
}
Paul Eggert's avatar
Paul Eggert committed
409

410

Dmitry Antipov's avatar
Dmitry Antipov committed
411 412 413 414 415
static Lisp_Object
make_lisp_proc (struct Lisp_Process *p)
{
  return make_lisp_ptr (p, Lisp_Vectorlike);
}
416

417 418 419 420 421 422 423 424 425 426 427 428 429 430 431
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
};

432
static struct fd_callback_data
433 434 435
{
  fd_callback func;
  void *data;
436 437
  /* Flags from enum fd_bits.  */
  int flags;
Tom Tromey's avatar
Tom Tromey committed
438 439 440 441 442 443 444
  /* 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;
445
} fd_callback_info[FD_SETSIZE];
446 447 448 449 450 451 452 453 454 455 456 457


/* 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;
458 459
}

Tom Tromey's avatar
Tom Tromey committed
460
static void
461 462
add_non_keyboard_read_fd (int fd)
{
Ken Raeburn's avatar
Ken Raeburn committed
463
  eassert (fd >= 0 && fd < FD_SETSIZE);
464
  eassert (fd_callback_info[fd].func == NULL);
Eli Zaretskii's avatar
Eli Zaretskii committed
465 466

  fd_callback_info[fd].flags &= ~KEYBOARD_FD;
467
  fd_callback_info[fd].flags |= FOR_READ;
Tom Tromey's avatar
Tom Tromey committed
468 469
  if (fd > max_desc)
    max_desc = fd;
470 471
}

Tom Tromey's avatar
Tom Tromey committed
472
static void
473 474 475 476
add_process_read_fd (int fd)
{
  add_non_keyboard_read_fd (fd);
  fd_callback_info[fd].flags |= PROCESS_FD;
477 478 479 480 481 482 483 484 485
}

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

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

486
  if (fd_callback_info[fd].flags == 0)
487 488 489 490 491 492 493 494 495 496 497 498
    {
      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
499
  eassert (fd >= 0 && fd < FD_SETSIZE);
500 501 502

  fd_callback_info[fd].func = func;
  fd_callback_info[fd].data = data;
503
  fd_callback_info[fd].flags |= FOR_WRITE;
Eli Zaretskii's avatar
Eli Zaretskii committed
504 505
  if (fd > max_desc)
    max_desc = fd;
506 507
}

Tom Tromey's avatar
Tom Tromey committed
508
static void
509 510
add_non_blocking_write_fd (int fd)
{
Ken Raeburn's avatar
Ken Raeburn committed
511
  eassert (fd >= 0 && fd < FD_SETSIZE);
512 513 514
  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
515 516
  if (fd > max_desc)
    max_desc = fd;
517
  ++num_pending_connects;
518
}
519 520

static void
Tom Tromey's avatar
Tom Tromey committed
521
recompute_max_desc (void)
522
{
Tom Tromey's avatar
Tom Tromey committed
523
  int fd;
524

Tom Tromey's avatar
Tom Tromey committed
525 526 527 528 529 530 531
  for (fd = max_desc; fd >= 0; --fd)
    {
      if (fd_callback_info[fd].flags != 0)
	{
	  max_desc = fd;
	  break;
	}
532 533 534
    }
}

535 536 537 538 539
/* Stop monitoring file descriptor FD for when write is possible.  */

void
delete_write_fd (int fd)
{
540 541 542
  if ((fd_callback_info[fd].flags & NON_BLOCKING_CONNECT_FD) != 0)
    {
      if (--num_pending_connects < 0)
Eli Zaretskii's avatar
Eli Zaretskii committed
543
	emacs_abort ();
544 545 546
    }
  fd_callback_info[fd].flags &= ~(FOR_WRITE | NON_BLOCKING_CONNECT_FD);
  if (fd_callback_info[fd].flags == 0)
547 548 549 550
    {
      fd_callback_info[fd].func = 0;
      fd_callback_info[fd].data = 0;

Tom Tromey's avatar
Tom Tromey committed
551 552
      if (fd == max_desc)
	recompute_max_desc ();
553 554 555 556
    }
}

static void
Ken Raeburn's avatar
Ken Raeburn committed
557
compute_input_wait_mask (fd_set *mask)
558 559
{
  int fd;
560

561
  FD_ZERO (mask);
Tom Tromey's avatar
Tom Tromey committed
562
  for (fd = 0; fd <= max_desc; ++fd)
563
    {
Tom Tromey's avatar
Tom Tromey committed
564 565 566 567 568 569
      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;
570
      if ((fd_callback_info[fd].flags & FOR_READ) != 0)
Tom Tromey's avatar
Tom Tromey committed
571 572 573 574
	{
	  FD_SET (fd, mask);
	  fd_callback_info[fd].waiting_thread = current_thread;
	}
575 576 577
    }
}

578
static void
Ken Raeburn's avatar
Ken Raeburn committed
579
compute_non_process_wait_mask (fd_set *mask)
580 581 582 583
{
  int fd;

  FD_ZERO (mask);
Tom Tromey's avatar
Tom Tromey committed
584
  for (fd = 0; fd <= max_desc; ++fd)
585
    {
Tom Tromey's avatar
Tom Tromey committed
586 587 588 589 590 591
      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;
592 593
      if ((fd_callback_info[fd].flags & FOR_READ) != 0
	  && (fd_callback_info[fd].flags & PROCESS_FD) == 0)
Tom Tromey's avatar
Tom Tromey committed
594 595 596 597
	{
	  FD_SET (fd, mask);
	  fd_callback_info[fd].waiting_thread = current_thread;
	}
598 599 600 601
    }
}

static void
Ken Raeburn's avatar
Ken Raeburn committed
602
compute_non_keyboard_wait_mask (fd_set *mask)
603 604 605 606
{
  int fd;

  FD_ZERO (mask);
Tom Tromey's avatar
Tom Tromey committed
607
  for (fd = 0; fd <= max_desc; ++fd)
608
    {
Tom Tromey's avatar
Tom Tromey committed
609 610 611 612 613 614
      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;
615 616
      if ((fd_callback_info[fd].flags & FOR_READ) != 0
	  && (fd_callback_info[fd].flags & KEYBOARD_FD) == 0)
Tom Tromey's avatar
Tom Tromey committed
617 618 619 620
	{
	  FD_SET (fd, mask);
	  fd_callback_info[fd].waiting_thread = current_thread;
	}
621 622 623 624
    }
}

static void
Ken Raeburn's avatar
Ken Raeburn committed
625
compute_write_mask (fd_set *mask)
626 627 628 629
{
  int fd;

  FD_ZERO (mask);
Tom Tromey's avatar
Tom Tromey committed
630
  for (fd = 0; fd <= max_desc; ++fd)
631
    {
Tom Tromey's avatar
Tom Tromey committed
632 633 634 635 636 637
      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;
638
      if ((fd_callback_info[fd].flags & FOR_WRITE) != 0)
Tom Tromey's avatar
Tom Tromey committed
639 640 641 642
	{
	  FD_SET (fd, mask);
	  fd_callback_info[fd].waiting_thread = current_thread;
	}
643 644 645
    }
}

Tom Tromey's avatar
Tom Tromey committed
646 647 648 649
static void
clear_waiting_thread_info (void)
{
  int fd;
650

Tom Tromey's avatar
Tom Tromey committed
651
  for (fd = 0; fd <= max_desc; ++fd)
Tom Tromey's avatar
Tom Tromey committed
652 653 654
    {
      if (fd_callback_info[fd].waiting_thread == current_thread)
	fd_callback_info[fd].waiting_thread = NULL;
655 656 657
    }
}

Jim Blandy's avatar
Jim Blandy committed
658 659 660 661

/* Compute the Lisp form of the process status, p->status, from
   the numeric status that was returned by `wait'.  */

662
static Lisp_Object status_convert (int);
663

664
static void
665
update_status (struct Lisp_Process *p)
Jim Blandy's avatar
Jim Blandy committed
666
{
667
  eassert (p->raw_status_new);
Paul Eggert's avatar
Paul Eggert committed
668
  pset_status (p, status_convert (p->raw_status));
669
  p->raw_status_new = 0;
Jim Blandy's avatar
Jim Blandy committed
670 671
}

672
/*  Convert a process status word in Unix format to
Jim Blandy's avatar
Jim Blandy committed
673 674
    the list that we use internally.  */

675
static Lisp_Object
676
status_convert (int w)
Jim Blandy's avatar
Jim Blandy committed
677 678 679 680
{
  if (WIFSTOPPED (w))
    return Fcons (Qstop, Fcons (make_number (WSTOPSIG (w)), Qnil));
  else if (WIFEXITED (w))
Paul Eggert's avatar
Paul Eggert committed
681
    return Fcons (Qexit, Fcons (make_number (WEXITSTATUS (w)),
Jim Blandy's avatar
Jim Blandy committed
682 683 684 685 686 687 688 689
				WCOREDUMP (w) ? Qt : Qnil));
  else if (WIFSIGNALED (w))
    return Fcons (Qsignal, Fcons (make_number (WTERMSIG (w)),
				  WCOREDUMP (w) ? Qt : Qnil));
  else
    return Qrun;
}

690 691 692 693 694 695 696 697
/* 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
698 699 700
/* Given a status-list, extract the three pieces of information
   and store them individually through the three pointers.  */

701
static void
702 703
decode_status (Lisp_Object l, Lisp_Object *symbol, Lisp_Object *code,
	       bool *coredump)
Jim Blandy's avatar
Jim Blandy committed
704 705 706
{
  Lisp_Object tem;

707 708 709
  if (connecting_status (l))
    l = XCAR (l);

710
  if (SYMBOLP (l))
Jim Blandy's avatar
Jim Blandy committed
711 712
    {
      *symbol = l;
713
      *code = make_number (0);
Jim Blandy's avatar
Jim Blandy committed
714 715 716 717
      *coredump = 0;
    }
  else
    {
718 719
      *symbol = XCAR (l);
      tem = XCDR (l);
720
      *code = XCAR (tem);
721
      tem = XCDR (tem);
Jim Blandy's avatar
Jim Blandy committed
722 723 724 725 726 727
      *coredump = !NILP (tem);
    }
}

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

728
static Lisp_Object
729
status_message (struct Lisp_Process *p)
Jim Blandy's avatar
Jim Blandy committed
730
{
731
  Lisp_Object status = p->status;
732
  Lisp_Object symbol, code;
733
  bool coredump;
734
  Lisp_Object string;
Jim Blandy's avatar
Jim Blandy committed
735 736 737 738 739

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

  if (EQ (symbol, Qsignal) || EQ (symbol, Qstop))
    {
740
      char const *signame;
741
      synchronize_system_messages_locale ();
742
      signame = strsignal (XFASTINT (code));
743
      if (signame == 0)
744 745 746 747 748
	string = build_string ("unknown");
      else
	{
	  int c1, c2;

749
	  string = build_unibyte_string (signame);
750 751 752
	  if (! NILP (Vlocale_coding_system))
	    string = (code_convert_string_norecord
		      (string, Vlocale_coding_system, 0));
753
	  c1 = STRING_CHAR (SDATA (string));
754
	  c2 = downcase (c1);
755
	  if (c1 != c2)
756
	    Faset (string, make_number (0), make_number (c2));
757
	}
758 759
      AUTO_STRING (suffix, coredump ? " (core dumped)\n" : "\n");
      return concat2 (string, suffix);
Jim Blandy's avatar
Jim Blandy committed
760 761 762
    }
  else if (EQ (symbol, Qexit))
    {
763
      if (NETCONN1_P (p))
764 765 766 767
	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
768
	return build_string ("finished\n");
769
      AUTO_STRING (prefix, "exited abnormally with code ");
770
      string = Fnumber_to_string (code);
771 772
      AUTO_STRING (suffix, coredump ? " (core dumped)\n" : "\n");
      return concat3 (prefix, string, suffix);
Jim Blandy's avatar
Jim Blandy committed
773
    }
774 775
  else if (EQ (symbol, Qfailed))
    {
776 777
      AUTO_STRING (format, "failed with code %s\n");
      return CALLN (Fformat, format, code);
778
    }
Jim Blandy's avatar
Jim Blandy committed
779 780 781 782
  else
    return Fcopy_sequence (Fsymbol_name (symbol));
}

783
enum { PTY_NAME_SIZE = 24 };
Dan Nicolaescu's avatar
Dan Nicolaescu committed
784

785
/* Open an available pty, returning a file descriptor.
786 787
   Store into PTY_NAME the file name of the terminal corresponding to the pty.
   Return -1 on failure.  */
788

789
static int
790
allocate_pty (char pty_name[PTY_NAME_SIZE])
Jim Blandy's avatar
Jim Blandy committed
791
{
792
#ifdef HAVE_PTYS
Jim Blandy's avatar
Jim Blandy committed
793 794 795 796 797
  int fd;

#ifdef PTY_ITERATION
  PTY_ITERATION
#else
798
  register int c, i;
Jim Blandy's avatar
Jim Blandy committed
799 800 801 802 803 804 805 806 807 808
  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 */

809 810 811
#ifdef PTY_OPEN
	PTY_OPEN;
#else /* no PTY_OPEN */
812
	fd = emacs_open (pty_name, O_RDWR | O_NONBLOCK, 0);
813
#endif /* no PTY_OPEN */
Jim Blandy's avatar
Jim Blandy committed
814 815 816

	if (fd >= 0)
	  {
817 818 819 820 821 822
#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 */

823 824 825
	    /* 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.
826 827
	       Do this after PTY_TTY_NAME_SPRINTF, which on some platforms
	       doesn't work if the close-on-exec flag is set (Bug#20555).
828 829 830 831
	       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);
832 833 834

	    /* Check to make certain that both sides are available.
	       This avoids a nasty yet stupid bug in rlogins.  */
835
	    if (faccessat (AT_FDCWD, pty_name, R_OK | W_OK, AT_EACCESS) != 0)
Jim Blandy's avatar
Jim Blandy committed
836
	      {
837
		emacs_close (fd);
Jim Blandy's avatar
Jim Blandy committed
838 839 840 841 842 843
		continue;
	      }
	    setup_pty (fd);
	    return fd;
	  }
      }
844
#endif /* HAVE_PTYS */
Jim Blandy's avatar
Jim Blandy committed
845 846
  return -1;
}
847 848 849 850 851 852 853 854 855

/* Allocate basically initialized process.  */

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

856
static Lisp_Object
857
make_process (Lisp_Object name)
Jim Blandy's avatar
Jim Blandy committed
858
{
859
  struct Lisp_Process *p = allocate_process ();
860 861
  /* 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
862 863
  pset_status (p, Qrun);
  pset_mark (p, Fmake_marker ());
Tom Tromey's avatar
Tom Tromey committed
864
  pset_thread (p, Fcurrent_thread ());
Jim Blandy's avatar
Jim Blandy committed
865

866 867 868 869
  /* 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;
870
  for (int i = 0; i < PROCESS_OPEN_FDS; i++)
871
    p->open_fd[i] = -1;
Kenichi Handa's avatar
Kenichi Handa committed
872

Ted Zlatanov's avatar
Ted Zlatanov committed
873
#ifdef HAVE_GNUTLS
874 875 876
  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
877 878
#endif

Jim Blandy's avatar
Jim Blandy committed
879 880
  /* If name is already in use, modify it until it is unused.  */

881 882
  Lisp_Object name1 = name;
  for (printmax_t i = 1; ; i++)
Jim Blandy's avatar
Jim Blandy committed
883
    {
884 885 886 887 888 889 890
      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
891 892
    }
  name = name1;
Paul Eggert's avatar
Paul Eggert committed
893
  pset_name (p, name);
894 895
  pset_sentinel (p, Qinternal_default_process_sentinel);
  pset_filter (p, Qinternal_default_process_filter);
896
  Lisp_Object val;
897
  XSETPROCESS (val, p);
Jim Blandy's avatar
Jim Blandy committed
898 899 900 901
  Vprocess_alist = Fcons (Fcons (name, val), Vprocess_alist);
  return val;
}

902
static void
903
remove_process (register Lisp_Object proc)
Jim Blandy's avatar
Jim Blandy committed
904 905 906 907 908 909 910 911
{
  register Lisp_Object pair;

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

  deactivate_process (proc);
}
912

Tom Tromey's avatar
Tom Tromey committed
913 914 915 916 917 918 919 920 921 922 923 924
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
925
	  pset_thread (proc, Qnil);
Tom Tromey's avatar
Tom Tromey committed
926 927 928 929 930 931 932 933
	  if (proc->infd >= 0)
	    fd_callback_info[proc->infd].thread = NULL;
	  if (proc->outfd >= 0)
	    fd_callback_info[proc->outfd].thread = NULL;
	}
    }
}

934 935 936 937 938 939
#ifdef HAVE_GETADDRINFO_A
static void
free_dns_request (Lisp_Object proc)
{
  struct Lisp_Process *p = XPROCESS (proc);

940 941 942 943
  if (p->dns_request->ar_result)
    freeaddrinfo (p->dns_request->ar_result);
  xfree (p->dns_request);
  p->dns_request = NULL;
944 945 946
}
#endif

Jim Blandy's avatar
Jim Blandy committed
947 948

DEFUN ("processp", Fprocessp, Sprocessp, 1, 1, 0,
949
       doc: /* Return t if OBJECT is a process.  */)
Dan Nicolaescu's avatar
Dan Nicolaescu committed
950
  (Lisp_Object object)
Jim Blandy's avatar
Jim Blandy committed
951
{
952
  return PROCESSP (object) ? Qt : Qnil;
Jim Blandy's avatar
Jim Blandy committed
953 954 955
}

DEFUN ("get-process", Fget_process, Sget_process, 1, 1, 0,
956
       doc: /* Return the process named NAME, or nil if there is none.  */)
Dan Nicolaescu's avatar
Dan Nicolaescu committed
957
  (register Lisp_Object name)
Jim Blandy's avatar
Jim Blandy committed
958
{
959
  if (PROCESSP (name))
Jim Blandy's avatar
Jim Blandy committed
960
    return name;
961
  CHECK_STRING (name);
962
  return Fcdr (Fassoc (name, Vprocess_alist, Qnil));
Jim Blandy's avatar
Jim Blandy committed
963 964
}

Jim Blandy's avatar
Jim Blandy committed
965 966 967 968
/* 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
969

970
static Lisp_Object
971
get_process (register Lisp_Object name)
Jim Blandy's avatar
Jim Blandy committed
972
{
973 974 975 976 977 978 979
  register Lisp_Object proc, obj;
  if (STRINGP (name))
    {
      obj = Fget_process (name);
      if (NILP (obj))
	obj = Fget_buffer (name);
      if (NILP (obj))
980
	error ("Process %s does not exist", SDATA (name));
981 982 983
    }
  else if (NILP (name))
    obj = Fcurrent_buffer ();
Jim Blandy's avatar
Jim Blandy committed
984
  else
985 986
    obj = name;

987 988
  /* Now obj should be either a buffer object or a process object.  */
  if (BUFFERP (obj))
Jim Blandy's avatar
Jim Blandy committed
989
    {
990 991
      if (NILP (BVAR (XBUFFER (obj), name)))
        error ("Attempt to get process for a dead buffer");
992
      proc = Fget_buffer_process (obj);
Jim Blandy's avatar
Jim Blandy committed
993
      if (NILP (proc))
994
        error ("Buffer %s has no process", SDATA (BVAR (XBUFFER (obj), name)));
Jim Blandy's avatar
Jim Blandy committed
995 996
    }
  else
997
    {
998
      CHECK_PROCESS (obj);
999 1000 1001
      proc = obj;
    }
  return proc;
Jim Blandy's avatar
Jim Blandy committed
1002 1003
}

1004 1005 1006

/* Fdelete_process promises to immediately forget about the process, but in
   reality, Emacs needs to remember those processes until they have been
1007
   treated by the SIGCHLD handler and waitpid has been invoked on them;
1008 1009
   otherwise they might fill up the kernel's process table.

1010 1011 1012 1013 1014
   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.  */
1015 1016
static Lisp_Object deleted_pid_list;

1017
void
1018
record_deleted_pid (pid_t pid, Lisp_Object filename)
1019
{
1020
  deleted_pid_list = Fcons (Fcons (make_fixnum_or_float (pid), filename),
1021 1022 1023 1024 1025
			    /* GC treated elements set to nil.  */
			    Fdelq (Qnil, deleted_pid_list));

}

Jim Blandy's avatar
Jim Blandy committed
1026
DEFUN ("delete-process", Fdelete_process, Sdelete_process, 1, 1, 0,
1027 1028 1029
       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
1030
  (register Lisp_Object process)
Jim Blandy's avatar
Jim Blandy committed
1031
{
1032 1033
  register struct Lisp_Process *p;

1034
  process = get_process (process);
1035 1036
  p = XPROCESS (process);

1037
#ifdef HAVE_GETADDRINFO_A
1038
  if (p->dns_request)
1039
    {
1040 1041
      /* Cancel the request.  Unless shutting down, wait until
	 completion.  Free the request if completely canceled. */
1042

1043 1044
      bool canceled = gai_cancel (p->dns_request) != EAI_NOTCANCELED;
      if (!canceled && !inhibit_sentinels)
1045
	{
1046 1047 1048 1049
	  struct gaicb const *req = p->dns_request;
	  while (gai_suspend (&req, 1, NULL) != 0)
	    continue;
	  canceled = true;
1050
	}
1051 1052
      if (canceled)
	free_dns_request (process);