stdio-common/printf.h

   1 /* Copyright (C) 1991, 92, 93, 95, 96 Free Software Foundation, Inc.
   2 This file is part of the GNU C Library.
   3
   4 The GNU C Library is free software; you can redistribute it and/or
   5 modify it under the terms of the GNU Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 License, or (at your option) any later version.
   8
   9 The GNU C Library is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #ifndef _PRINTF_H
  20
  21 #define _PRINTF_H       1
  22 #include <features.h>
  23
  24 __BEGIN_DECLS
  25
  26 #define __need_FILE
  27 #include <stdio.h>
  28 #define __need_size_t
  29 #define __need_wchar_t
  30 #include <stddef.h>
  31
  32
  33 struct printf_info
  34 {
  35   int prec;                     /* Precision.  */
  36   int width;                    /* Width.  */
  37   wchar_t spec;                 /* Format letter.  */
  38   unsigned int is_long_double:1;/* L flag.  */
  39   unsigned int is_short:1;      /* h flag.  */
  40   unsigned int is_long:1;       /* l flag.  */
  41   unsigned int alt:1;           /* # flag.  */
  42   unsigned int space:1;         /* Space flag.  */
  43   unsigned int left:1;          /* - flag.  */
  44   unsigned int showsign:1;      /* + flag.  */
  45   unsigned int group:1;         /* ' flag.  */
  46   unsigned int extra:1;         /* For special use.  */
  47   char pad;                     /* Padding character.  */
  48 };
  49
  50
  51 /* Type of a printf specifier-handler function.
  52    STREAM is the FILE on which to write output.
  53    INFO gives information about the format specification.
  54    ARGS is a vector of pointers to the argument data;
  55    the number of pointers will be the number returned
  56    by the associated arginfo function for the same INFO.
  57
  58    The function should return the number of characters written,
  59    or -1 for errors.  */
  60
  61 typedef int printf_function __P ((FILE *__stream,
  62                                   __const struct printf_info *__info,
  63                                   __const void *__const *__args));
  64
  65 /* Type of a printf specifier-arginfo function.
  66    INFO gives information about the format specification.
  67    N, ARGTYPES, and return value are as for printf_parse_format.  */
  68
  69 typedef int printf_arginfo_function __P ((__const struct printf_info * __info,
  70                                           size_t __n,
  71                                           int *__argtypes));
  72
  73
  74 /* Register FUNC to be called to format SPEC specifiers; ARGINFO must be
  75    specified to determine how many arguments a SPEC conversion requires and
  76    what their types are, even if your program never calls
  77    `parse_printf_format'.  */
  78
  79 extern int register_printf_function __P ((int __spec, printf_function __func,
  80                                           printf_arginfo_function __arginfo));
  81
  82
  83 /* Parse FMT, and fill in N elements of ARGTYPES with the
  84    types needed for the conversions FMT specifies.  Returns
  85    the number of arguments required by FMT.
  86
  87    The ARGINFO function registered with a user-defined format is passed a
  88    `struct printf_info' describing the format spec being parsed.  A width
  89    or precision of INT_MIN means a `*' was used to indicate that the
  90    width/precision will come from an arg.  The function should fill in the
  91    array it is passed with the types of the arguments it wants, and return
  92    the number of arguments it wants.  */
  93
  94 extern size_t parse_printf_format __P ((__const char *__fmt,
  95                                         size_t __n,
  96                                         int *__argtypes));
  97
  98
  99 /* Codes returned by `parse_printf_format' for basic types.
 100
 101    These values cover all the standard format specifications.
 102    Users can add new values after PA_LAST for their own types.  */
 103
 104 enum
 105 {                               /* C type: */
 106   PA_INT,                       /* int */
 107   PA_CHAR,                      /* int, cast to char */
 108   PA_STRING,                    /* const char *, a '\0'-terminated string */
 109   PA_POINTER,                   /* void * */
 110   PA_FLOAT,                     /* float */
 111   PA_DOUBLE,                    /* double */
 112   PA_LAST
 113 };
 114
 115 /* Flag bits that can be set in a type returned by `parse_printf_format'.  */
 116 #define PA_FLAG_MASK            0xff00
 117 #define PA_FLAG_LONG_LONG       (1 << 8)
 118 #define PA_FLAG_LONG_DOUBLE     PA_FLAG_LONG_LONG
 119 #define PA_FLAG_LONG            (1 << 9)
 120 #define PA_FLAG_SHORT           (1 << 10)
 121 #define PA_FLAG_PTR             (1 << 11)
 122
 123
 124 __END_DECLS
 125
 126 #endif /* printf.h  */