lib/error.in.h

   1 /* Declarations for error-reporting functions.
   2    Copyright (C) 1995-1997, 2003, 2006, 2008-2024 Free Software Foundation,
   3    Inc.
   4    This file is part of the GNU C Library.
   5
   6    This file is free software: you can redistribute it and/or modify
   7    it under the terms of the GNU Lesser General Public License as
   8    published by the Free Software Foundation; either version 2.1 of the
   9    License, or (at your option) any later version.
  10
  11    This file 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 Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public License
  17    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _@GUARD_PREFIX@_ERROR_H
  20
  21 /* No @PRAGMA_SYSTEM_HEADER@ here, because it would prevent
  22    -Wimplicit-fallthrough warnings for missing FALLTHROUGH after error(...)
  23    or error_at_line(...) invocations.  */
  24
  25 /* The include_next requires a split double-inclusion guard.  */
  26 #if @HAVE_ERROR_H@
  27 # @INCLUDE_NEXT@ @NEXT_ERROR_H@
  28 #endif
  29
  30 #ifndef _@GUARD_PREFIX@_ERROR_H
  31 #define _@GUARD_PREFIX@_ERROR_H
  32
  33 /* This file uses _GL_ATTRIBUTE_ALWAYS_INLINE, _GL_ATTRIBUTE_FORMAT,
  34   _GL_ATTRIBUTE_MAYBE_UNUSED.  */
  35 #if !_GL_CONFIG_H_INCLUDED
  36  #error "Please include config.h first."
  37 #endif
  38
  39 /* Get 'unreachable'.  */
  40 #include <stddef.h>
  41
  42 /* Get _GL_ATTRIBUTE_SPEC_PRINTF_STANDARD, _GL_ATTRIBUTE_SPEC_PRINTF_SYSTEM.  */
  43 #include <stdio.h>
  44
  45 /* The definitions of _GL_FUNCDECL_RPL etc. are copied here.  */
  46
  47 #if GNULIB_VFPRINTF_POSIX
  48 # define _GL_ATTRIBUTE_SPEC_PRINTF_ERROR _GL_ATTRIBUTE_SPEC_PRINTF_STANDARD
  49 #else
  50 # define _GL_ATTRIBUTE_SPEC_PRINTF_ERROR _GL_ATTRIBUTE_SPEC_PRINTF_SYSTEM
  51 #endif
  52
  53 /* Helper macro for supporting the compiler's control flow analysis better.
  54    It evaluates its arguments only once.
  55    Test case: Compile copy-file.c with "gcc -Wimplicit-fallthrough".  */
  56 #if defined __GNUC__ || defined __clang__
  57 /* Use 'unreachable' to tell the compiler when the function call does not
  58    return.  */
  59 # define __gl_error_call1(function, status, ...) \
  60     ((function) (status, __VA_ARGS__), \
  61      (status) != 0 ? unreachable () : (void) 0)
  62 /* If STATUS is a not a constant, the function call may or may not return;
  63    therefore -Wimplicit-fallthrough will produce a warning.  Use a compound
  64    statement in order to evaluate STATUS only once.
  65    If STATUS is a constant, we don't use a compound statement, because that
  66    would trigger a -Wimplicit-fallthrough warning even when STATUS is != 0,
  67    when not optimizing.  This causes STATUS to be evaluated twice, but
  68    that's OK since it does not have side effects.  */
  69 # define __gl_error_call(function, status, ...)                 \
  70     (__builtin_constant_p (status)                              \
  71      ? __gl_error_call1 (function, status, __VA_ARGS__)         \
  72      : __extension__                                            \
  73        ({                                                       \
  74          int const __errstatus = status;                        \
  75          __gl_error_call1 (function, __errstatus, __VA_ARGS__); \
  76        }))
  77 #else
  78 # define __gl_error_call(function, status, ...) \
  79     (function) (status, __VA_ARGS__)
  80 #endif
  81
  82 #ifdef __cplusplus
  83 extern "C" {
  84 #endif
  85
  86 /* Print a message with 'fprintf (stderr, FORMAT, ...)';
  87    if ERRNUM is nonzero, follow it with ": " and strerror (ERRNUM).
  88    If STATUS is nonzero, terminate the program with 'exit (STATUS)'.  */
  89 #if @REPLACE_ERROR@
  90 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
  91 #  undef error
  92 #  define error rpl_error
  93 # endif
  94 _GL_FUNCDECL_RPL (error, void,
  95                   (int __status, int __errnum, const char *__format, ...)
  96                   _GL_ATTRIBUTE_FORMAT ((_GL_ATTRIBUTE_SPEC_PRINTF_ERROR, 3, 4)));
  97 _GL_CXXALIAS_RPL (error, void,
  98                   (int __status, int __errnum, const char *__format, ...));
  99 # ifndef _GL_NO_INLINE_ERROR
 100 #  undef error
 101 #  define error(status, ...) \
 102      __gl_error_call (rpl_error, status, __VA_ARGS__)
 103 # endif
 104 #else
 105 # if ! @HAVE_ERROR@
 106 _GL_FUNCDECL_SYS (error, void,
 107                   (int __status, int __errnum, const char *__format, ...)
 108                   _GL_ATTRIBUTE_FORMAT ((_GL_ATTRIBUTE_SPEC_PRINTF_ERROR, 3, 4)));
 109 # endif
 110 _GL_CXXALIAS_SYS (error, void,
 111                   (int __status, int __errnum, const char *__format, ...));
 112 # ifndef _GL_NO_INLINE_ERROR
 113 #  ifdef error
 114 /* Only gcc ≥ 4.7 has __builtin_va_arg_pack.  */
 115 #   if _GL_GNUC_PREREQ (4, 7)
 116 #    pragma GCC diagnostic push
 117 #    pragma GCC diagnostic ignored "-Wattributes"
 118 _GL_ATTRIBUTE_MAYBE_UNUSED
 119 static void
 120 _GL_ATTRIBUTE_ALWAYS_INLINE
 121 _GL_ATTRIBUTE_FORMAT ((_GL_ATTRIBUTE_SPEC_PRINTF_ERROR, 3, 4))
 122 _gl_inline_error (int __status, int __errnum, const char *__format, ...)
 123 {
 124   return error (__status, __errnum, __format, __builtin_va_arg_pack ());
 125 }
 126 #    pragma GCC diagnostic pop
 127 #    undef error
 128 #    define error(status, ...) \
 129        __gl_error_call (_gl_inline_error, status, __VA_ARGS__)
 130 #   endif
 131 #  else
 132 #   define error(status, ...) \
 133       __gl_error_call (error, status, __VA_ARGS__)
 134 #  endif
 135 # endif
 136 #endif
 137 #if __GLIBC__ >= 2
 138 _GL_CXXALIASWARN (error);
 139 #endif
 140
 141 /* Likewise.  If FILENAME is non-NULL, include FILENAME:LINENO: in the
 142    message.  */
 143 #if @REPLACE_ERROR_AT_LINE@
 144 # if !(defined __cplusplus && defined GNULIB_NAMESPACE)
 145 #  undef error_at_line
 146 #  define error_at_line rpl_error_at_line
 147 # endif
 148 _GL_FUNCDECL_RPL (error_at_line, void,
 149                   (int __status, int __errnum, const char *__filename,
 150                    unsigned int __lineno, const char *__format, ...)
 151                   _GL_ATTRIBUTE_FORMAT ((_GL_ATTRIBUTE_SPEC_PRINTF_ERROR, 5, 6)));
 152 _GL_CXXALIAS_RPL (error_at_line, void,
 153                   (int __status, int __errnum, const char *__filename,
 154                    unsigned int __lineno, const char *__format, ...));
 155 # ifndef _GL_NO_INLINE_ERROR
 156 #  undef error_at_line
 157 #  define error_at_line(status, ...) \
 158      __gl_error_call (rpl_error_at_line, status, __VA_ARGS__)
 159 # endif
 160 #else
 161 # if ! @HAVE_ERROR_AT_LINE@
 162 _GL_FUNCDECL_SYS (error_at_line, void,
 163                   (int __status, int __errnum, const char *__filename,
 164                    unsigned int __lineno, const char *__format, ...)
 165                   _GL_ATTRIBUTE_FORMAT ((_GL_ATTRIBUTE_SPEC_PRINTF_ERROR, 5, 6)));
 166 # endif
 167 _GL_CXXALIAS_SYS (error_at_line, void,
 168                   (int __status, int __errnum, const char *__filename,
 169                    unsigned int __lineno, const char *__format, ...));
 170 # ifndef _GL_NO_INLINE_ERROR
 171 #  ifdef error_at_line
 172 /* Only gcc ≥ 4.7 has __builtin_va_arg_pack.  */
 173 #   if _GL_GNUC_PREREQ (4, 7)
 174 #    pragma GCC diagnostic push
 175 #    pragma GCC diagnostic ignored "-Wattributes"
 176 _GL_ATTRIBUTE_MAYBE_UNUSED
 177 static void
 178 _GL_ATTRIBUTE_ALWAYS_INLINE
 179 _GL_ATTRIBUTE_FORMAT ((_GL_ATTRIBUTE_SPEC_PRINTF_ERROR, 5, 6))
 180 _gl_inline_error_at_line (int __status, int __errnum, const char *__filename,
 181                           unsigned int __lineno, const char *__format, ...)
 182 {
 183   return error_at_line (__status, __errnum, __filename, __lineno, __format,
 184                         __builtin_va_arg_pack ());
 185 }
 186 #    pragma GCC diagnostic pop
 187 #    undef error_at_line
 188 #    define error_at_line(status, ...) \
 189        __gl_error_call (_gl_inline_error_at_line, status, __VA_ARGS__)
 190 #   endif
 191 #  else
 192 #   define error_at_line(status, ...) \
 193       __gl_error_call (error_at_line, status, __VA_ARGS__)
 194 #  endif
 195 # endif
 196 #endif
 197 _GL_CXXALIASWARN (error_at_line);
 198
 199 /* If NULL, error will flush stdout, then print on stderr the program
 200    name, a colon and a space.  Otherwise, error will call this
 201    function without parameters instead.  */
 202 extern void (*error_print_progname) (void);
 203
 204 /* This variable is incremented each time 'error' is called.  */
 205 extern unsigned int error_message_count;
 206
 207 /* Sometimes we want to have at most one error per line.  This
 208    variable controls whether this mode is selected or not.  */
 209 extern int error_one_per_line;
 210
 211 #ifdef __cplusplus
 212 }
 213 #endif
 214
 215 #endif /* _@GUARD_PREFIX@_ERROR_H */
 216 #endif /* _@GUARD_PREFIX@_ERROR_H */