libio/bits/stdio.h

   1 /* Optimizing macros and inline functions for stdio functions.
   2    Copyright (C) 1998-2024 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 #ifndef _BITS_STDIO_H
  20 #define _BITS_STDIO_H 1
  21
  22 #ifndef _STDIO_H
  23 # error "Never include <bits/stdio.h> directly; use <stdio.h> instead."
  24 #endif
  25
  26 #ifndef __extern_inline
  27 # define __STDIO_INLINE inline
  28 #else
  29 # define __STDIO_INLINE __extern_inline
  30 #endif
  31
  32
  33 #ifdef __USE_EXTERN_INLINES
  34 /* For -D_FORTIFY_SOURCE{,=2,=3} bits/stdio2.h will define a different
  35    inline.  */
  36 # if !(__USE_FORTIFY_LEVEL > 0 && defined __fortify_function)
  37 /* Write formatted output to stdout from argument list ARG.  */
  38 __STDIO_INLINE int
  39 vprintf (const char *__restrict __fmt, __gnuc_va_list __arg)
  40 {
  41   return vfprintf (stdout, __fmt, __arg);
  42 }
  43 # endif
  44
  45 /* Read a character from stdin.  */
  46 __STDIO_INLINE int
  47 getchar (void)
  48 {
  49   return getc (stdin);
  50 }
  51
  52
  53 # ifdef __USE_MISC
  54 /* Faster version when locking is not necessary.  */
  55 __STDIO_INLINE int
  56 fgetc_unlocked (FILE *__fp)
  57 {
  58   return __getc_unlocked_body (__fp);
  59 }
  60 # endif /* misc */
  61
  62
  63 # ifdef __USE_POSIX199506
  64 /* This is defined in POSIX.1:1996.  */
  65 __STDIO_INLINE int
  66 getc_unlocked (FILE *__fp)
  67 {
  68   return __getc_unlocked_body (__fp);
  69 }
  70
  71 /* This is defined in POSIX.1:1996.  */
  72 __STDIO_INLINE int
  73 getchar_unlocked (void)
  74 {
  75   return __getc_unlocked_body (stdin);
  76 }
  77 # endif /* POSIX */
  78
  79
  80 /* Write a character to stdout.  */
  81 __STDIO_INLINE int
  82 putchar (int __c)
  83 {
  84   return putc (__c, stdout);
  85 }
  86
  87
  88 # ifdef __USE_MISC
  89 /* Faster version when locking is not necessary.  */
  90 __STDIO_INLINE int
  91 fputc_unlocked (int __c, FILE *__stream)
  92 {
  93   return __putc_unlocked_body (__c, __stream);
  94 }
  95 # endif /* misc */
  96
  97
  98 # ifdef __USE_POSIX199506
  99 /* This is defined in POSIX.1:1996.  */
 100 __STDIO_INLINE int
 101 putc_unlocked (int __c, FILE *__stream)
 102 {
 103   return __putc_unlocked_body (__c, __stream);
 104 }
 105
 106 /* This is defined in POSIX.1:1996.  */
 107 __STDIO_INLINE int
 108 putchar_unlocked (int __c)
 109 {
 110   return __putc_unlocked_body (__c, stdout);
 111 }
 112 # endif /* POSIX */
 113
 114
 115 # ifdef __USE_GNU
 116 /* Like `getdelim', but reads up to a newline.  */
 117 __STDIO_INLINE __ssize_t
 118 getline (char **__lineptr, size_t *__n, FILE *__stream)
 119 {
 120   return __getdelim (__lineptr, __n, '\n', __stream);
 121 }
 122 # endif /* GNU */
 123
 124
 125 # ifdef __USE_MISC
 126 /* Faster versions when locking is not required.  */
 127 __STDIO_INLINE int
 128 __NTH (feof_unlocked (FILE *__stream))
 129 {
 130   return __feof_unlocked_body (__stream);
 131 }
 132
 133 /* Faster versions when locking is not required.  */
 134 __STDIO_INLINE int
 135 __NTH (ferror_unlocked (FILE *__stream))
 136 {
 137   return __ferror_unlocked_body (__stream);
 138 }
 139 # endif /* misc */
 140
 141 #endif /* Use extern inlines.  */
 142
 143
 144 #if defined __USE_MISC && defined __GNUC__ && defined __OPTIMIZE__ \
 145     && !defined __cplusplus
 146 /* Perform some simple optimizations.  */
 147 # define fread_unlocked(ptr, size, n, stream) \
 148   (__extension__ ((__builtin_constant_p (size) && __builtin_constant_p (n)    \
 149                    && (size_t) (size) * (size_t) (n) <= 8                     \
 150                    && (size_t) (size) != 0)                                   \
 151                   ? ({ char *__ptr = (char *) (ptr);                          \
 152                        FILE *__stream = (stream);                             \
 153                        size_t __cnt;                                          \
 154                        for (__cnt = (size_t) (size) * (size_t) (n);           \
 155                             __cnt > 0; --__cnt)                               \
 156                          {                                                    \
 157                            int __c = getc_unlocked (__stream);                \
 158                            if (__c == EOF)                                    \
 159                              break;                                           \
 160                            *__ptr++ = __c;                                    \
 161                          }                                                    \
 162                        ((size_t) (size) * (size_t) (n) - __cnt)               \
 163                         / (size_t) (size); })                                 \
 164                   : (((__builtin_constant_p (size) && (size_t) (size) == 0)   \
 165                       || (__builtin_constant_p (n) && (size_t) (n) == 0))     \
 166                         /* Evaluate all parameters once.  */                  \
 167                      ? ((void) (ptr), (void) (stream), (void) (size),         \
 168                         (void) (n), (size_t) 0)                               \
 169                      : fread_unlocked (ptr, size, n, stream))))
 170
 171 # define fwrite_unlocked(ptr, size, n, stream) \
 172   (__extension__ ((__builtin_constant_p (size) && __builtin_constant_p (n)    \
 173                    && (size_t) (size) * (size_t) (n) <= 8                     \
 174                    && (size_t) (size) != 0)                                   \
 175                   ? ({ const char *__ptr = (const char *) (ptr);              \
 176                        FILE *__stream = (stream);                             \
 177                        size_t __cnt;                                          \
 178                        for (__cnt = (size_t) (size) * (size_t) (n);           \
 179                             __cnt > 0; --__cnt)                               \
 180                          if (putc_unlocked (*__ptr++, __stream) == EOF)       \
 181                            break;                                             \
 182                        ((size_t) (size) * (size_t) (n) - __cnt)               \
 183                         / (size_t) (size); })                                 \
 184                   : (((__builtin_constant_p (size) && (size_t) (size) == 0)   \
 185                       || (__builtin_constant_p (n) && (size_t) (n) == 0))     \
 186                         /* Evaluate all parameters once.  */                  \
 187                      ? ((void) (ptr), (void) (stream), (void) (size),         \
 188                         (void) (n), (size_t) 0)                               \
 189                      : fwrite_unlocked (ptr, size, n, stream))))
 190 #endif
 191
 192 /* Define helper macro.  */
 193 #undef __STDIO_INLINE
 194
 195 #endif /* bits/stdio.h.  */