lib/argp-fmtstream.h

   1 /* Word-wrapping and line-truncating streams.
   2    Copyright (C) 1997-2024 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Written by Miles Bader <miles@gnu.ai.mit.edu>.
   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 3 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 /* This package emulates glibc 'line_wrap_stream' semantics for systems that
  20    don't have that.  If the system does have it, it is just a wrapper for
  21    that.  This header file is only used internally while compiling argp, and
  22    shouldn't be installed.  */
  23
  24 #ifndef _ARGP_FMTSTREAM_H
  25 #define _ARGP_FMTSTREAM_H
  26
  27 /* This file uses _GL_INLINE_HEADER_BEGIN, __GL_INLINE, _GL_ATTRIBUTE_DEALLOC,
  28    _GL_ATTRIBUTE_FORMAT.  */
  29 #if !_LIBC && !_GL_CONFIG_H_INCLUDED
  30  #error "Please include config.h first."
  31 #endif
  32
  33 #include <stdio.h>
  34 #include <string.h>
  35 #include <unistd.h>
  36
  37 #if defined (__GNU_LIBRARY__) && defined (HAVE_LINEWRAP_H)
  38 /* line_wrap_stream is available, so use that.  */
  39 #define ARGP_FMTSTREAM_USE_LINEWRAP
  40 #endif
  41
  42 #ifdef ARGP_FMTSTREAM_USE_LINEWRAP
  43 /* Just be a simple wrapper for line_wrap_stream; the semantics are
  44    *slightly* different, as line_wrap_stream doesn't actually make a new
  45    object, it just modifies the given stream (reversibly) to do
  46    line-wrapping.  Since we control who uses this code, it doesn't matter.  */
  47
  48 #include <linewrap.h>
  49
  50 typedef FILE *argp_fmtstream_t;
  51
  52 #define argp_make_fmtstream line_wrap_stream
  53 #define __argp_make_fmtstream line_wrap_stream
  54 #define argp_fmtstream_free line_unwrap_stream
  55 #define __argp_fmtstream_free line_unwrap_stream
  56
  57 #define __argp_fmtstream_putc(fs,ch) putc(ch,fs)
  58 #define argp_fmtstream_putc(fs,ch) putc(ch,fs)
  59 #define __argp_fmtstream_puts(fs,str) fputs(str,fs)
  60 #define argp_fmtstream_puts(fs,str) fputs(str,fs)
  61 #define __argp_fmtstream_write(fs,str,len) fwrite(str,1,len,fs)
  62 #define argp_fmtstream_write(fs,str,len) fwrite(str,1,len,fs)
  63 #define __argp_fmtstream_printf fprintf
  64 #define argp_fmtstream_printf fprintf
  65
  66 #define __argp_fmtstream_lmargin line_wrap_lmargin
  67 #define argp_fmtstream_lmargin line_wrap_lmargin
  68 #define __argp_fmtstream_set_lmargin line_wrap_set_lmargin
  69 #define argp_fmtstream_set_lmargin line_wrap_set_lmargin
  70 #define __argp_fmtstream_rmargin line_wrap_rmargin
  71 #define argp_fmtstream_rmargin line_wrap_rmargin
  72 #define __argp_fmtstream_set_rmargin line_wrap_set_rmargin
  73 #define argp_fmtstream_set_rmargin line_wrap_set_rmargin
  74 #define __argp_fmtstream_wmargin line_wrap_wmargin
  75 #define argp_fmtstream_wmargin line_wrap_wmargin
  76 #define __argp_fmtstream_set_wmargin line_wrap_set_wmargin
  77 #define argp_fmtstream_set_wmargin line_wrap_set_wmargin
  78 #define __argp_fmtstream_point line_wrap_point
  79 #define argp_fmtstream_point line_wrap_point
  80
  81 #else /* !ARGP_FMTSTREAM_USE_LINEWRAP */
  82 /* Guess we have to define our own version.  */
  83
  84 \f
  85 struct argp_fmtstream
  86 {
  87   FILE *stream;                 /* The stream we're outputting to.  */
  88
  89   size_t lmargin, rmargin;      /* Left and right margins.  */
  90   ssize_t wmargin;              /* Margin to wrap to, or -1 to truncate.  */
  91
  92   /* Point in buffer to which we've processed for wrapping, but not output.  */
  93   size_t point_offs;
  94   /* Output column at POINT_OFFS, or -1 meaning 0 but don't add lmargin.  */
  95   ssize_t point_col;
  96
  97   char *buf;                    /* Output buffer.  */
  98   char *p;                      /* Current end of text in BUF. */
  99   char *end;                    /* Absolute end of BUF.  */
 100 };
 101
 102 typedef struct argp_fmtstream *argp_fmtstream_t;
 103
 104 /* Flush __FS to its stream, and free it (but don't close the stream).  */
 105 extern void __argp_fmtstream_free (argp_fmtstream_t __fs);
 106 extern void argp_fmtstream_free (argp_fmtstream_t __fs);
 107
 108 /* Return an argp_fmtstream that outputs to STREAM, and which prefixes lines
 109    written on it with LMARGIN spaces and limits them to RMARGIN columns
 110    total.  If WMARGIN >= 0, words that extend past RMARGIN are wrapped by
 111    replacing the whitespace before them with a newline and WMARGIN spaces.
 112    Otherwise, chars beyond RMARGIN are simply dropped until a newline.
 113    Returns NULL if there was an error.  */
 114 extern argp_fmtstream_t __argp_make_fmtstream (FILE *__stream,
 115                                                size_t __lmargin,
 116                                                size_t __rmargin,
 117                                                ssize_t __wmargin)
 118   _GL_ATTRIBUTE_DEALLOC (__argp_fmtstream_free, 1);
 119 extern argp_fmtstream_t argp_make_fmtstream (FILE *__stream,
 120                                              size_t __lmargin,
 121                                              size_t __rmargin,
 122                                              ssize_t __wmargin)
 123   _GL_ATTRIBUTE_DEALLOC (argp_fmtstream_free, 1);
 124
 125 extern ssize_t __argp_fmtstream_printf (argp_fmtstream_t __fs,
 126                                         const char *__fmt, ...)
 127      _GL_ATTRIBUTE_FORMAT ((printf, 2, 3));
 128 extern ssize_t argp_fmtstream_printf (argp_fmtstream_t __fs,
 129                                       const char *__fmt, ...)
 130      _GL_ATTRIBUTE_FORMAT ((printf, 2, 3));
 131
 132 #if _LIBC
 133 extern int __argp_fmtstream_putc (argp_fmtstream_t __fs, int __ch);
 134 extern int argp_fmtstream_putc (argp_fmtstream_t __fs, int __ch);
 135
 136 extern int __argp_fmtstream_puts (argp_fmtstream_t __fs, const char *__str);
 137 extern int argp_fmtstream_puts (argp_fmtstream_t __fs, const char *__str);
 138
 139 extern size_t __argp_fmtstream_write (argp_fmtstream_t __fs,
 140                                       const char *__str, size_t __len);
 141 extern size_t argp_fmtstream_write (argp_fmtstream_t __fs,
 142                                     const char *__str, size_t __len);
 143 #endif
 144 \f
 145 /* Access macros for various bits of state.  */
 146 #define argp_fmtstream_lmargin(__fs) ((__fs)->lmargin)
 147 #define argp_fmtstream_rmargin(__fs) ((__fs)->rmargin)
 148 #define argp_fmtstream_wmargin(__fs) ((__fs)->wmargin)
 149 #define __argp_fmtstream_lmargin argp_fmtstream_lmargin
 150 #define __argp_fmtstream_rmargin argp_fmtstream_rmargin
 151 #define __argp_fmtstream_wmargin argp_fmtstream_wmargin
 152
 153 #if _LIBC
 154 /* Set __FS's left margin to LMARGIN and return the old value.  */
 155 extern size_t argp_fmtstream_set_lmargin (argp_fmtstream_t __fs,
 156                                           size_t __lmargin);
 157 extern size_t __argp_fmtstream_set_lmargin (argp_fmtstream_t __fs,
 158                                             size_t __lmargin);
 159
 160 /* Set __FS's right margin to __RMARGIN and return the old value.  */
 161 extern size_t argp_fmtstream_set_rmargin (argp_fmtstream_t __fs,
 162                                           size_t __rmargin);
 163 extern size_t __argp_fmtstream_set_rmargin (argp_fmtstream_t __fs,
 164                                             size_t __rmargin);
 165
 166 /* Set __FS's wrap margin to __WMARGIN and return the old value.  */
 167 extern size_t argp_fmtstream_set_wmargin (argp_fmtstream_t __fs,
 168                                           size_t __wmargin);
 169 extern size_t __argp_fmtstream_set_wmargin (argp_fmtstream_t __fs,
 170                                             size_t __wmargin);
 171
 172 /* Return the column number of the current output point in __FS.  */
 173 extern size_t argp_fmtstream_point (argp_fmtstream_t __fs);
 174 extern size_t __argp_fmtstream_point (argp_fmtstream_t __fs);
 175 #endif
 176
 177 /* Internal routines.  */
 178 extern void _argp_fmtstream_update (argp_fmtstream_t __fs);
 179 extern void __argp_fmtstream_update (argp_fmtstream_t __fs);
 180 extern int _argp_fmtstream_ensure (argp_fmtstream_t __fs, size_t __amount);
 181 extern int __argp_fmtstream_ensure (argp_fmtstream_t __fs, size_t __amount);
 182 \f
 183 #if !_LIBC || defined __OPTIMIZE__
 184 /* Inline versions of above routines.  */
 185
 186 #if !_LIBC
 187 #define __argp_fmtstream_putc argp_fmtstream_putc
 188 #define __argp_fmtstream_puts argp_fmtstream_puts
 189 #define __argp_fmtstream_write argp_fmtstream_write
 190 #define __argp_fmtstream_set_lmargin argp_fmtstream_set_lmargin
 191 #define __argp_fmtstream_set_rmargin argp_fmtstream_set_rmargin
 192 #define __argp_fmtstream_set_wmargin argp_fmtstream_set_wmargin
 193 #define __argp_fmtstream_point argp_fmtstream_point
 194 #define __argp_fmtstream_update _argp_fmtstream_update
 195 #define __argp_fmtstream_ensure _argp_fmtstream_ensure
 196 _GL_INLINE_HEADER_BEGIN
 197 #ifndef ARGP_FS_EI
 198 # define ARGP_FS_EI _GL_INLINE
 199 #endif
 200 #endif
 201
 202 #ifndef ARGP_FS_EI
 203 #define ARGP_FS_EI extern inline
 204 #endif
 205
 206 ARGP_FS_EI size_t
 207 __argp_fmtstream_write (argp_fmtstream_t __fs, const char *__str, size_t __len)
 208 {
 209   if (__fs->p + __len <= __fs->end || __argp_fmtstream_ensure (__fs, __len))
 210     {
 211       memcpy (__fs->p, __str, __len);
 212       __fs->p += __len;
 213       return __len;
 214     }
 215   else
 216     return 0;
 217 }
 218
 219 ARGP_FS_EI int
 220 __argp_fmtstream_puts (argp_fmtstream_t __fs, const char *__str)
 221 {
 222   size_t __len = strlen (__str);
 223   if (__len)
 224     {
 225       size_t __wrote = __argp_fmtstream_write (__fs, __str, __len);
 226       return __wrote == __len ? 0 : -1;
 227     }
 228   else
 229     return 0;
 230 }
 231
 232 ARGP_FS_EI int
 233 __argp_fmtstream_putc (argp_fmtstream_t __fs, int __ch)
 234 {
 235   if (__fs->p < __fs->end || __argp_fmtstream_ensure (__fs, 1))
 236     return *__fs->p++ = __ch;
 237   else
 238     return EOF;
 239 }
 240
 241 /* Set __FS's left margin to __LMARGIN and return the old value.  */
 242 ARGP_FS_EI size_t
 243 __argp_fmtstream_set_lmargin (argp_fmtstream_t __fs, size_t __lmargin)
 244 {
 245   size_t __old;
 246   if ((size_t) (__fs->p - __fs->buf) > __fs->point_offs)
 247     __argp_fmtstream_update (__fs);
 248   __old = __fs->lmargin;
 249   __fs->lmargin = __lmargin;
 250   return __old;
 251 }
 252
 253 /* Set __FS's right margin to __RMARGIN and return the old value.  */
 254 ARGP_FS_EI size_t
 255 __argp_fmtstream_set_rmargin (argp_fmtstream_t __fs, size_t __rmargin)
 256 {
 257   size_t __old;
 258   if ((size_t) (__fs->p - __fs->buf) > __fs->point_offs)
 259     __argp_fmtstream_update (__fs);
 260   __old = __fs->rmargin;
 261   __fs->rmargin = __rmargin;
 262   return __old;
 263 }
 264
 265 /* Set FS's wrap margin to __WMARGIN and return the old value.  */
 266 ARGP_FS_EI size_t
 267 __argp_fmtstream_set_wmargin (argp_fmtstream_t __fs, size_t __wmargin)
 268 {
 269   size_t __old;
 270   if ((size_t) (__fs->p - __fs->buf) > __fs->point_offs)
 271     __argp_fmtstream_update (__fs);
 272   __old = __fs->wmargin;
 273   __fs->wmargin = __wmargin;
 274   return __old;
 275 }
 276
 277 /* Return the column number of the current output point in __FS.  */
 278 ARGP_FS_EI size_t
 279 __argp_fmtstream_point (argp_fmtstream_t __fs)
 280 {
 281   if ((size_t) (__fs->p - __fs->buf) > __fs->point_offs)
 282     __argp_fmtstream_update (__fs);
 283   return __fs->point_col >= 0 ? __fs->point_col : 0;
 284 }
 285
 286 #if !_LIBC
 287 #undef __argp_fmtstream_putc
 288 #undef __argp_fmtstream_puts
 289 #undef __argp_fmtstream_write
 290 #undef __argp_fmtstream_set_lmargin
 291 #undef __argp_fmtstream_set_rmargin
 292 #undef __argp_fmtstream_set_wmargin
 293 #undef __argp_fmtstream_point
 294 #undef __argp_fmtstream_update
 295 #undef __argp_fmtstream_ensure
 296 _GL_INLINE_HEADER_END
 297 #endif
 298
 299 #endif /* !_LIBC || __OPTIMIZE__ */
 300
 301 #endif /* ARGP_FMTSTREAM_USE_LINEWRAP */
 302
 303 #endif /* argp-fmtstream.h */