src/process.h

   1 /* Definitions for asynchronous process control in GNU Emacs.
   2    Copyright (C) 1985, 1994, 2001-2018 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software: you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation, either version 3 of the License, or (at
   9 your option) any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef EMACS_PROCESS_H
  20 #define EMACS_PROCESS_H
  21
  22 #ifdef HAVE_SYS_TYPES_H
  23 #include <sys/types.h>
  24 #endif
  25
  26 #include <unistd.h>
  27
  28 #ifdef HAVE_GNUTLS
  29 #include "gnutls.h"
  30 #endif
  31
  32 INLINE_HEADER_BEGIN
  33
  34 /* Bound on number of file descriptors opened on behalf of a process,
  35    that need to be closed.  */
  36
  37 enum { PROCESS_OPEN_FDS = 6 };
  38
  39 /* This structure records information about a subprocess
  40    or network connection.  */
  41
  42 struct Lisp_Process
  43   {
  44     union vectorlike_header header;
  45
  46     /* Name of subprocess terminal.  */
  47     Lisp_Object tty_name;
  48
  49     /* Name of this process.  */
  50     Lisp_Object name;
  51
  52     /* List of command arguments that this process was run with.
  53        Is set to t for a stopped network process; nil otherwise.  */
  54     Lisp_Object command;
  55
  56     /* (funcall FILTER PROC STRING)  (if FILTER is non-nil)
  57        to dispose of a bunch of chars from the process all at once.  */
  58     Lisp_Object filter;
  59
  60     /* (funcall SENTINEL PROCESS) when process state changes.  */
  61     Lisp_Object sentinel;
  62
  63     /* (funcall LOG SERVER CLIENT MESSAGE) when a server process
  64        accepts a connection from a client.  */
  65     Lisp_Object log;
  66
  67     /* Buffer that output is going to.  */
  68     Lisp_Object buffer;
  69
  70     /* t if this is a real child process.  For a network or serial
  71        connection, it is a plist based on the arguments to
  72        make-network-process or make-serial-process.  */
  73
  74     Lisp_Object childp;
  75
  76     /* Plist for programs to keep per-process state information, parameters, etc.  */
  77     Lisp_Object plist;
  78
  79     /* Symbol indicating the type of process: real, network, serial.  */
  80     Lisp_Object type;
  81
  82     /* Marker set to end of last buffer-inserted output from this process.  */
  83     Lisp_Object mark;
  84
  85     /* Symbol indicating status of process.
  86        This may be a symbol: run, open, closed, listen, or failed.
  87        Or it may be a pair (connect . ADDRINFOS) where ADDRINFOS is
  88        a list of remaining (PROTOCOL . ADDRINFO) pairs to try.
  89        Or it may be (failed ERR) where ERR is an integer, string or symbol.
  90        Or it may be a list, whose car is stop, exit or signal
  91        and whose cdr is a pair (EXIT_CODE . COREDUMP_FLAG)
  92        or (SIGNAL_NUMBER . COREDUMP_FLAG).  */
  93     Lisp_Object status;
  94
  95     /* Coding-system for decoding the input from this process.  */
  96     Lisp_Object decode_coding_system;
  97
  98     /* Working buffer for decoding.  */
  99     Lisp_Object decoding_buf;
 100
 101     /* Coding-system for encoding the output to this process.  */
 102     Lisp_Object encode_coding_system;
 103
 104     /* Working buffer for encoding.  */
 105     Lisp_Object encoding_buf;
 106
 107     /* Queue for storing waiting writes.  */
 108     Lisp_Object write_queue;
 109
 110 #ifdef HAVE_GNUTLS
 111     Lisp_Object gnutls_cred_type;
 112     Lisp_Object gnutls_boot_parameters;
 113 #endif
 114
 115     /* Pipe process attached to the standard error of this process.  */
 116     Lisp_Object stderrproc;
 117
 118     /* The thread a process is linked to, or nil for any thread.  */
 119     Lisp_Object thread;
 120
 121     /* After this point, there are no Lisp_Objects any more.  */
 122     /* alloc.c assumes that `pid' is the first such non-Lisp slot.  */
 123
 124     /* Process ID.  A positive value is a child process ID.
 125        Zero is for pseudo-processes such as network or serial connections,
 126        or for processes that have not been fully created yet.
 127        -1 is for a process that was not created successfully.
 128        -2 is for a pty with no process, e.g., for GDB.  */
 129     pid_t pid;
 130     /* Descriptor by which we read from this process.  */
 131     int infd;
 132     /* Byte-count modulo (UINTMAX_MAX + 1) for process output read from `infd'.  */
 133     uintmax_t nbytes_read;
 134     /* Descriptor by which we write to this process.  */
 135     int outfd;
 136     /* Descriptors that were created for this process and that need
 137        closing.  Unused entries are negative.  */
 138     int open_fd[PROCESS_OPEN_FDS];
 139     /* Event-count of last event in which this process changed status.  */
 140     EMACS_INT tick;
 141     /* Event-count of last such event reported.  */
 142     EMACS_INT update_tick;
 143     /* Size of carryover in decoding.  */
 144     int decoding_carryover;
 145     /* Hysteresis to try to read process output in larger blocks.
 146        On some systems, e.g. GNU/Linux, Emacs is seen as
 147        an interactive app also when reading process output, meaning
 148        that process output can be read in as little as 1 byte at a
 149        time.  Value is nanoseconds to delay reading output from
 150        this process.  Range is 0 .. 50 * 1000 * 1000.  */
 151     int read_output_delay;
 152     /* Should we delay reading output from this process.
 153        Initialized from `Vprocess_adaptive_read_buffering'.
 154        0 = nil, 1 = t, 2 = other.  */
 155     unsigned int adaptive_read_buffering : 2;
 156     /* Skip reading this process on next read.  */
 157     bool_bf read_output_skip : 1;
 158     /* True means kill silently if Emacs is exited.
 159        This is the inverse of the `query-on-exit' flag.  */
 160     bool_bf kill_without_query : 1;
 161     /* True if communicating through a pty.  */
 162     bool_bf pty_flag : 1;
 163     /* Flag to set coding-system of the process buffer from the
 164        coding_system used to decode process output.  */
 165     bool_bf inherit_coding_system_flag : 1;
 166     /* Whether the process is alive, i.e., can be waited for.  Running
 167        processes can be waited for, but exited and fake processes cannot.  */
 168     bool_bf alive : 1;
 169     /* Record the process status in the raw form in which it comes from `wait'.
 170        This is to avoid consing in a signal handler.  The `raw_status_new'
 171        flag indicates that `raw_status' contains a new status that still
 172        needs to be synced to `status'.  */
 173     bool_bf raw_status_new : 1;
 174     /* Whether this is a nonblocking socket. */
 175     bool_bf is_non_blocking_client : 1;
 176     /* Whether this is a server or a client socket. */
 177     bool_bf is_server : 1;
 178     int raw_status;
 179     /* The length of the socket backlog. */
 180     int backlog;
 181     /* The port number. */
 182     int port;
 183     /* The socket type. */
 184     int socktype;
 185
 186 #ifdef HAVE_GETADDRINFO_A
 187     /* Whether the socket is waiting for response from an asynchronous
 188        DNS call. */
 189     struct gaicb *dns_request;
 190 #endif
 191
 192 #ifdef HAVE_GNUTLS
 193     gnutls_initstage_t gnutls_initstage;
 194     gnutls_session_t gnutls_state;
 195     gnutls_certificate_client_credentials gnutls_x509_cred;
 196     gnutls_anon_client_credentials_t gnutls_anon_cred;
 197     gnutls_x509_crt_t gnutls_certificate;
 198     unsigned int gnutls_peer_verification;
 199     unsigned int gnutls_extra_peer_verification;
 200     int gnutls_log_level;
 201     int gnutls_handshakes_tried;
 202     bool_bf gnutls_p : 1;
 203     bool_bf gnutls_complete_negotiation_p : 1;
 204 #endif
 205 };
 206
 207 INLINE bool
 208 PROCESSP (Lisp_Object a)
 209 {
 210   return PSEUDOVECTORP (a, PVEC_PROCESS);
 211 }
 212
 213 INLINE void
 214 CHECK_PROCESS (Lisp_Object x)
 215 {
 216   CHECK_TYPE (PROCESSP (x), Qprocessp, x);
 217 }
 218
 219 INLINE struct Lisp_Process *
 220 XPROCESS (Lisp_Object a)
 221 {
 222   eassert (PROCESSP (a));
 223   return XUNTAG (a, Lisp_Vectorlike);
 224 }
 225
 226 /* Every field in the preceding structure except for the first two
 227    must be a Lisp_Object, for GC's sake.  */
 228
 229 #define ChannelMask(n) (1 << (n))
 230
 231 /* Most code should use these functions to set Lisp fields in struct
 232    process.  */
 233
 234 INLINE void
 235 pset_childp (struct Lisp_Process *p, Lisp_Object val)
 236 {
 237   p->childp = val;
 238 }
 239
 240 INLINE void
 241 pset_status (struct Lisp_Process *p, Lisp_Object val)
 242 {
 243   p->status = val;
 244 }
 245
 246 #ifdef HAVE_GNUTLS
 247 INLINE void
 248 pset_gnutls_cred_type (struct Lisp_Process *p, Lisp_Object val)
 249 {
 250   p->gnutls_cred_type = val;
 251 }
 252 #endif
 253
 254 /* True means don't run process sentinels.  This is used
 255    when exiting.  */
 256 extern bool inhibit_sentinels;
 257
 258 /* Exit statuses for GNU programs that exec other programs.  */
 259 enum
 260 {
 261   EXIT_CANCELED = 125, /* Internal error prior to exec attempt.  */
 262   EXIT_CANNOT_INVOKE = 126, /* Program located, but not usable.  */
 263   EXIT_ENOENT = 127 /* Could not find program to exec.  */
 264 };
 265
 266 /* Defined in callproc.c.  */
 267
 268 extern Lisp_Object encode_current_directory (void);
 269 extern void record_kill_process (struct Lisp_Process *, Lisp_Object);
 270
 271 /* Defined in sysdep.c.  */
 272
 273 extern Lisp_Object list_system_processes (void);
 274 extern Lisp_Object system_process_attributes (Lisp_Object);
 275
 276 /* Defined in process.c.  */
 277
 278 extern void record_deleted_pid (pid_t, Lisp_Object);
 279 struct sockaddr;
 280 extern Lisp_Object conv_sockaddr_to_lisp (struct sockaddr *, ptrdiff_t);
 281 extern void hold_keyboard_input (void);
 282 extern void unhold_keyboard_input (void);
 283 extern bool kbd_on_hold_p (void);
 284
 285 typedef void (*fd_callback) (int fd, void *data);
 286
 287 extern void add_read_fd (int fd, fd_callback func, void *data);
 288 extern void delete_read_fd (int fd);
 289 extern void add_write_fd (int fd, fd_callback func, void *data);
 290 extern void delete_write_fd (int fd);
 291 extern void catch_child_signal (void);
 292 extern void restore_nofile_limit (void);
 293
 294 #ifdef WINDOWSNT
 295 extern Lisp_Object network_interface_list (void);
 296 extern Lisp_Object network_interface_info (Lisp_Object);
 297 #endif
 298
 299 extern Lisp_Object remove_slash_colon (Lisp_Object);
 300
 301 extern void update_processes_for_thread_death (Lisp_Object);
 302
 303 INLINE_HEADER_END
 304
 305 #endif /* EMACS_PROCESS_H */