support/support.h

   1 /* Common extra functions.
   2    Copyright (C) 2016-2020 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    <https://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 /* For mode_t.  */
  29 #include <sys/stat.h>
  30 /* For ssize_t and off64_t.  */
  31 #include <sys/types.h>
  32 /* For locale_t.  */
  33 #include <locale.h>
  34
  35 __BEGIN_DECLS
  36
  37 /* Write a message to standard output.  Can be used in signal
  38    handlers.  */
  39 void write_message (const char *message) __attribute__ ((nonnull (1)));
  40
  41 /* Avoid all the buffer overflow messages on stderr.  */
  42 void ignore_stderr (void);
  43
  44 /* Set fortification error handler.  Used when tests want to verify that bad
  45    code is caught by the library.  */
  46 void set_fortify_handler (void (*handler) (int sig));
  47
  48 /* Report an out-of-memory error for the allocation of SIZE bytes in
  49    FUNCTION, terminating the process.  */
  50 void oom_error (const char *function, size_t size)
  51   __attribute__ ((nonnull (1)));
  52
  53 /* Return a pointer to a memory region of SIZE bytes.  The memory is
  54    initialized to zero and will be shared with subprocesses (across
  55    fork).  The returned pointer must be freed using
  56    support_shared_free; it is not compatible with the malloc
  57    functions.  */
  58 void *support_shared_allocate (size_t size);
  59
  60 /* Deallocate a pointer returned by support_shared_allocate.  */
  61 void support_shared_free (void *);
  62
  63 /* Write CONTENTS to the file PATH.  Create or truncate the file as
  64    needed.  The file mode is 0666 masked by the umask.  Terminate the
  65    process on error.  */
  66 void support_write_file_string (const char *path, const char *contents);
  67
  68 /* Quote the contents of the byte array starting at BLOB, of LENGTH
  69    bytes, in such a way that the result string can be included in a C
  70    literal (in single/double quotes, without putting the quotes into
  71    the result).  */
  72 char *support_quote_blob (const void *blob, size_t length);
  73
  74 /* Quote the contents of the string, in such a way that the result
  75    string can be included in a C literal (in single/double quotes,
  76    without putting the quotes into the result).  */
  77 char *support_quote_string (const char *);
  78
  79 /* Returns non-zero if the file descriptor is a regular file on a file
  80    system which supports holes (that is, seeking and writing does not
  81    allocate storage for the range of zeros).  FD must refer to a
  82    regular file open for writing, and initially empty.  */
  83 int support_descriptor_supports_holes (int fd);
  84
  85 /* Error-checking wrapper functions which terminate the process on
  86    error.  */
  87
  88 void *xmalloc (size_t) __attribute__ ((malloc));
  89 void *xcalloc (size_t n, size_t s) __attribute__ ((malloc));
  90 void *xrealloc (void *p, size_t n);
  91 void *xposix_memalign (size_t alignment, size_t n);
  92 char *xasprintf (const char *format, ...)
  93   __attribute__ ((format (printf, 1, 2), malloc));
  94 char *xstrdup (const char *);
  95 char *xstrndup (const char *, size_t);
  96 char *xsetlocale (int category, const char *locale);
  97 locale_t xnewlocale (int category_mask, const char *locale, locale_t base);
  98 char *xuselocale (locale_t newloc);
  99
 100 /* These point to the TOP of the source/build tree, not your (or
 101    support's) subdirectory.  */
 102 extern const char support_srcdir_root[];
 103 extern const char support_objdir_root[];
 104
 105 /* Corresponds to the path to the runtime linker used by the testsuite,
 106    e.g. OBJDIR_PATH/elf/ld-linux-x86-64.so.2  */
 107 extern const char support_objdir_elf_ldso[];
 108
 109 /* Corresponds to the --prefix= passed to configure.  */
 110 extern const char support_install_prefix[];
 111 /* Corresponds to the install's lib/ or lib64/ directory.  */
 112 extern const char support_libdir_prefix[];
 113 /* Corresponds to the install's bin/ directory.  */
 114 extern const char support_bindir_prefix[];
 115 /* Corresponds to the install's sbin/ directory.  */
 116 extern const char support_sbindir_prefix[];
 117 /* Corresponds to the install's system /lib or /lib64 directory.  */
 118 extern const char support_slibdir_prefix[];
 119 /* Corresponds to the install's sbin/ directory (without prefix).  */
 120 extern const char support_install_rootsbindir[];
 121 /* Corresponds to the install's compiled locale directory.  */
 122 extern const char support_complocaledir_prefix[];
 123
 124 /* Copies the file at the path FROM to TO.  If TO does not exist, it
 125    is created.  If TO is a regular file, it is truncated before
 126    copying.  The file mode is copied, but the permissions are not.  */
 127 extern void support_copy_file (const char *from, const char *to);
 128
 129 extern ssize_t support_copy_file_range (int, off64_t *, int, off64_t *,
 130                                         size_t, unsigned int);
 131
 132 __END_DECLS
 133
 134 #endif /* SUPPORT_H */