support/support.h

   1 /* Common extra functions.
   2    Copyright (C) 2016-2017 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 /* This header file should only contain definitions compatible with
  20    C90.  (Using __attribute__ is fine because <features.h> provides a
  21    fallback.)  */
  22
  23 #ifndef SUPPORT_H
  24 #define SUPPORT_H
  25
  26 #include <stddef.h>
  27 #include <sys/cdefs.h>
  28
  29 __BEGIN_DECLS
  30
  31 /* Write a message to standard output.  Can be used in signal
  32    handlers.  */
  33 void write_message (const char *message) __attribute__ ((nonnull (1)));
  34
  35 /* Avoid all the buffer overflow messages on stderr.  */
  36 void ignore_stderr (void);
  37
  38 /* Set fortification error handler.  Used when tests want to verify that bad
  39    code is caught by the library.  */
  40 void set_fortify_handler (void (*handler) (int sig));
  41
  42 /* Report an out-of-memory error for the allocation of SIZE bytes in
  43    FUNCTION, terminating the process.  */
  44 void oom_error (const char *function, size_t size)
  45   __attribute__ ((nonnull (1)));
  46
  47 /* Return a pointer to a memory region of SIZE bytes.  The memory is
  48    initialized to zero and will be shared with subprocesses (across
  49    fork).  The returned pointer must be freed using
  50    support_shared_free; it is not compatible with the malloc
  51    functions.  */
  52 void *support_shared_allocate (size_t size);
  53
  54 /* Deallocate a pointer returned by support_shared_allocate.  */
  55 void support_shared_free (void *);
  56
  57 /* Write CONTENTS to the file PATH.  Create or truncate the file as
  58    needed.  The file mode is 0666 masked by the umask.  Terminate the
  59    process on error.  */
  60 void support_write_file_string (const char *path, const char *contents);
  61
  62 /* Error-checking wrapper functions which terminate the process on
  63    error.  */
  64
  65 void *xmalloc (size_t) __attribute__ ((malloc));
  66 void *xcalloc (size_t n, size_t s) __attribute__ ((malloc));
  67 void *xrealloc (void *p, size_t n);
  68 char *xasprintf (const char *format, ...)
  69   __attribute__ ((format (printf, 1, 2), malloc));
  70 char *xstrdup (const char *);
  71 char *xstrndup (const char *, size_t);
  72
  73 __END_DECLS
  74
  75 #endif /* SUPPORT_H */