iconv/gconv.h

   1 /* Copyright (C) 1997-2022 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 Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the 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    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 /* This header provides no interface for a user to the internals of
  19    the gconv implementation in the libc.  Therefore there is no use
  20    for these definitions beside for writing additional gconv modules.  */
  21
  22 #ifndef _GCONV_H
  23 #define _GCONV_H        1
  24
  25 #include <features.h>
  26 #include <bits/types/__mbstate_t.h>
  27 #include <bits/types/wint_t.h>
  28
  29 #define __need_size_t
  30 #define __need_wchar_t
  31 #include <stddef.h>
  32
  33 /* ISO 10646 value used to signal invalid value.  */
  34 #define __UNKNOWN_10646_CHAR    ((wchar_t) 0xfffd)
  35
  36 /* Error codes for gconv functions.  */
  37 enum
  38 {
  39   __GCONV_OK = 0,
  40   __GCONV_NOCONV,
  41   __GCONV_NODB,
  42   __GCONV_NOMEM,
  43
  44   __GCONV_EMPTY_INPUT,
  45   __GCONV_FULL_OUTPUT,
  46   __GCONV_ILLEGAL_INPUT,
  47   __GCONV_INCOMPLETE_INPUT,
  48
  49   __GCONV_ILLEGAL_DESCRIPTOR,
  50   __GCONV_INTERNAL_ERROR
  51 };
  52
  53
  54 /* Flags the `__gconv_open' function can set.  */
  55 enum
  56 {
  57   __GCONV_IS_LAST = 0x0001,
  58   __GCONV_IGNORE_ERRORS = 0x0002,
  59   __GCONV_SWAP = 0x0004,
  60   __GCONV_TRANSLIT = 0x0008
  61 };
  62
  63
  64 /* Forward declarations.  */
  65 struct __gconv_step;
  66 struct __gconv_step_data;
  67 struct __gconv_loaded_object;
  68
  69
  70 /* Type of a conversion function.  */
  71 typedef int (*__gconv_fct) (struct __gconv_step *, struct __gconv_step_data *,
  72                             const unsigned char **, const unsigned char *,
  73                             unsigned char **, size_t *, int, int);
  74
  75 /* Type of a specialized conversion function for a single byte to INTERNAL.  */
  76 typedef wint_t (*__gconv_btowc_fct) (struct __gconv_step *, unsigned char);
  77
  78 /* Constructor and destructor for local data for conversion step.  */
  79 typedef int (*__gconv_init_fct) (struct __gconv_step *);
  80 typedef void (*__gconv_end_fct) (struct __gconv_step *);
  81
  82
  83 /* Description of a conversion step.  */
  84 struct __gconv_step
  85 {
  86   struct __gconv_loaded_object *__shlib_handle;
  87   const char *__modname;
  88
  89   /* For internal use by glibc.  (Accesses to this member must occur
  90      when the internal __gconv_lock mutex is acquired).  */
  91   int __counter;
  92
  93   char *__from_name;
  94   char *__to_name;
  95
  96   __gconv_fct __fct;
  97   __gconv_btowc_fct __btowc_fct;
  98   __gconv_init_fct __init_fct;
  99   __gconv_end_fct __end_fct;
 100
 101   /* Information about the number of bytes needed or produced in this
 102      step.  This helps optimizing the buffer sizes.  */
 103   int __min_needed_from;
 104   int __max_needed_from;
 105   int __min_needed_to;
 106   int __max_needed_to;
 107
 108   /* Flag whether this is a stateful encoding or not.  */
 109   int __stateful;
 110
 111   void *__data;         /* Pointer to step-local data.  */
 112 };
 113
 114 /* Additional data for steps in use of conversion descriptor.  This is
 115    allocated by the `init' function.  */
 116 struct __gconv_step_data
 117 {
 118   unsigned char *__outbuf;    /* Output buffer for this step.  */
 119   unsigned char *__outbufend; /* Address of first byte after the output
 120                                  buffer.  */
 121
 122   /* Is this the last module in the chain.  */
 123   int __flags;
 124
 125   /* Counter for number of invocations of the module function for this
 126      descriptor.  */
 127   int __invocation_counter;
 128
 129   /* Flag whether this is an internal use of the module (in the mb*towc*
 130      and wc*tomb* functions) or regular with iconv(3).  */
 131   int __internal_use;
 132
 133   __mbstate_t *__statep;
 134   __mbstate_t __state;  /* This element must not be used directly by
 135                            any module; always use STATEP!  */
 136 };
 137
 138
 139 /* Combine conversion step description with data.  */
 140 typedef struct __gconv_info
 141 {
 142   size_t __nsteps;
 143   struct __gconv_step *__steps;
 144   __extension__ struct __gconv_step_data __data[0];
 145 } *__gconv_t;
 146
 147 #endif /* gconv.h */