src/s/gnu-linux.h

   1 /* This file is the configuration file for Linux-based GNU systems
   2
   3 Copyright (C) 1985-1986, 1992, 1994, 1996, 1999, 2001-2012
   4   Free Software Foundation, Inc.
   5
   6 This file was put together by Michael K. Johnson and Rik Faith.
   7
   8 This file is part of GNU Emacs.
   9
  10 GNU Emacs is free software: you can redistribute it and/or modify
  11 it under the terms of the GNU General Public License as published by
  12 the Free Software Foundation, either version 3 of the License, or
  13 (at your option) any later version.
  14
  15 GNU Emacs is distributed in the hope that it will be useful,
  16 but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 GNU General Public License for more details.
  19
  20 You should have received a copy of the GNU General Public License
  21 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  22
  23 /* Define symbols to identify the version of Unix this is.
  24    Define all the symbols that apply correctly.  */
  25 #define USG
  26 #define GNU_LINUX
  27
  28 #if defined HAVE_GRANTPT
  29 #define UNIX98_PTYS
  30
  31 /* Run only once.  We need a `for'-loop because the code uses `continue'.  */
  32 #define PTY_ITERATION   int i; for (i = 0; i < 1; i++)
  33
  34 #ifdef HAVE_GETPT
  35 #define PTY_NAME_SPRINTF
  36 #define PTY_OPEN fd = getpt ()
  37 #else /* not HAVE_GETPT */
  38 #define PTY_NAME_SPRINTF strcpy (pty_name, "/dev/ptmx");
  39 #endif /* not HAVE_GETPT */
  40
  41 /* Note that grantpt and unlockpt may fork.  We must block SIGCHLD to
  42    prevent sigchld_handler from intercepting the child's death.  */
  43 #define PTY_TTY_NAME_SPRINTF                            \
  44   {                                                     \
  45     char *ptyname;                                      \
  46                                                         \
  47     sigblock (sigmask (SIGCHLD));                       \
  48     if (grantpt (fd) == -1 || unlockpt (fd) == -1       \
  49         || !(ptyname = ptsname(fd)))                    \
  50       {                                                 \
  51         sigunblock (sigmask (SIGCHLD));                 \
  52         close (fd);                                     \
  53         return -1;                                      \
  54       }                                                 \
  55     snprintf (pty_name, sizeof pty_name, "%s", ptyname); \
  56     sigunblock (sigmask (SIGCHLD));                     \
  57   }
  58
  59 #else /* not HAVE_GRANTPT */
  60
  61 /* Letter to use in finding device name of first pty,
  62    if system supports pty's.  'p' means it is /dev/ptyp0  */
  63 #define FIRST_PTY_LETTER 'p'
  64
  65 #endif  /* not HAVE_GRANTPT */
  66
  67 /* Define HAVE_PTYS if the system supports pty devices.  */
  68 #define HAVE_PTYS
  69
  70 #define HAVE_SOCKETS
  71
  72 /* Here, on a separate page, add any special hacks needed
  73    to make Emacs work on this system.  For example,
  74    you might define certain system call names that don't
  75    exist on your system, or that do different things on
  76    your system and must be used only through an encapsulation
  77    (Which you should place, by convention, in sysdep.c).  */
  78 \f
  79 #define POSIX                 /* affects getpagesize.h and systty.h */
  80
  81 /* This is to work around mysterious gcc failures in some system versions.
  82    It is unlikely that Emacs changes will work around this problem;
  83    therefore, this should remain permanently.  */
  84 #ifndef HAVE_XRMSETDATABASE
  85 #define HAVE_XRMSETDATABASE
  86 #endif
  87
  88 #define NARROWPROTO 1
  89
  90 #ifdef __ia64__
  91 #define GC_MARK_SECONDARY_STACK()                               \
  92   do {                                                          \
  93     extern void *__libc_ia64_register_backing_store_base;       \
  94     __builtin_ia64_flushrs ();                                  \
  95     mark_memory (__libc_ia64_register_backing_store_base,       \
  96                  __builtin_ia64_bsp ());                        \
  97   } while (0)
  98 #endif
  99
 100 /* Tell that garbage collector that setjmp is known to save all
 101    registers relevant for conservative garbage collection in the jmp_buf.
 102    Not all the architectures are tested, but there are Debian packages
 103    for SCM and/or Guile on them, so the technique must work.  See also
 104    comments in alloc.c concerning setjmp and gcc.  Fixme:  it's
 105    probably safe to just let the GCC conditional in AH_BOTTOM handle this.
 106 */
 107 #if defined __i386__ || defined __sparc__ || defined __mc68000__ \
 108     || defined __alpha__ || defined __mips__ || defined __s390__ \
 109     || defined __arm__ || defined __powerpc__ || defined __amd64__ \
 110     || defined __ia64__ || defined __sh__
 111 #define GC_SETJMP_WORKS 1
 112 #else
 113 #define GC_MARK_STACK GC_USE_GCPROS_AS_BEFORE
 114 #endif
 115
 116 #ifdef __i386__
 117 /* libc-linux/sysdeps/linux/i386/ulimit.c says that due to shared library, */
 118 /* we cannot get the maximum address for brk */
 119 # define ULIMIT_BREAK_VALUE (32*1024*1024)
 120 #endif