lib/textstyle.in.h

   1 /* Dummy replacement for part of the public API of the libtextstyle library.
   2    Copyright (C) 2006-2007, 2019-2020 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program 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
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Bruno Haible <bruno@clisp.org>, 2019.  */
  18
  19 /* This file is used as replacement when libtextstyle with its include file
  20    <textstyle.h> is not found.
  21    It supports the essential API and implements it in a way that does not
  22    provide text styling.  That is, it produces plain text output via <stdio.h>
  23    FILE objects.
  24    Thus, it allows a package to be build with or without a dependency to
  25    libtextstyle, with very few occurrences of '#if HAVE_LIBTEXTSTYLE'.
  26
  27    Restriction:
  28    It assumes that freopen() is not being called on stdout and stderr.  */
  29
  30 #ifndef _TEXTSTYLE_H
  31 #define _TEXTSTYLE_H
  32
  33 #include <errno.h>
  34 #include <stdarg.h>
  35 #include <stdbool.h>
  36 #include <stddef.h>
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <string.h>
  40 #include <unistd.h>
  41 #if HAVE_TCDRAIN
  42 # include <termios.h>
  43 #endif
  44
  45 /* ----------------------------- From ostream.h ----------------------------- */
  46
  47 /* Describes the scope of a flush operation.  */
  48 typedef enum
  49 {
  50   /* Flushes buffers in this ostream_t.
  51      Use this value if you want to write to the underlying ostream_t.  */
  52   FLUSH_THIS_STREAM = 0,
  53   /* Flushes all buffers in the current process.
  54      Use this value if you want to write to the same target through a
  55      different file descriptor or a FILE stream.  */
  56   FLUSH_THIS_PROCESS = 1,
  57   /* Flushes buffers in the current process and attempts to flush the buffers
  58      in the kernel.
  59      Use this value so that some other process (or the kernel itself)
  60      may write to the same target.  */
  61   FLUSH_ALL = 2
  62 } ostream_flush_scope_t;
  63
  64
  65 /* An output stream is an object to which one can feed a sequence of bytes.  */
  66
  67 typedef FILE * ostream_t;
  68
  69 static inline void
  70 ostream_write_mem (ostream_t stream, const void *data, size_t len)
  71 {
  72   if (len > 0)
  73     fwrite (data, 1, len, stream);
  74 }
  75
  76 static inline void
  77 ostream_flush (ostream_t stream, ostream_flush_scope_t scope)
  78 {
  79   fflush (stream);
  80   if (scope == FLUSH_ALL)
  81     {
  82       int fd = fileno (stream);
  83       if (fd >= 0)
  84         {
  85           /* For streams connected to a disk file:  */
  86           fsync (fd);
  87           #if HAVE_TCDRAIN
  88           /* For streams connected to a terminal:  */
  89           {
  90             int retval;
  91
  92             do
  93               retval = tcdrain (fd);
  94             while (retval < 0 && errno == EINTR);
  95           }
  96           #endif
  97         }
  98     }
  99 }
 100
 101 static inline void
 102 ostream_free (ostream_t stream)
 103 {
 104   if (stream == stdin || stream == stderr)
 105     fflush (stream);
 106   else
 107     fclose (stream);
 108 }
 109
 110 static inline void
 111 ostream_write_str (ostream_t stream, const char *string)
 112 {
 113   ostream_write_mem (stream, string, strlen (string));
 114 }
 115
 116 static inline ptrdiff_t ostream_printf (ostream_t stream,
 117                                         const char *format, ...)
 118 #if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1) || defined __clang__
 119   __attribute__ ((__format__ (__printf__, 2, 3)))
 120 #endif
 121   ;
 122 static inline ptrdiff_t
 123 ostream_printf (ostream_t stream, const char *format, ...)
 124 {
 125   va_list args;
 126   char *temp_string;
 127   ptrdiff_t ret;
 128
 129   va_start (args, format);
 130   ret = vasprintf (&temp_string, format, args);
 131   va_end (args);
 132   if (ret >= 0)
 133     {
 134       if (ret > 0)
 135         ostream_write_str (stream, temp_string);
 136       free (temp_string);
 137     }
 138   return ret;
 139 }
 140
 141 static inline ptrdiff_t ostream_vprintf (ostream_t stream,
 142                                          const char *format, va_list args)
 143 #if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1) || defined __clang__
 144   __attribute__ ((__format__ (__printf__, 2, 0)))
 145 #endif
 146   ;
 147 static inline ptrdiff_t
 148 ostream_vprintf (ostream_t stream, const char *format, va_list args)
 149 {
 150   char *temp_string;
 151   ptrdiff_t ret = vasprintf (&temp_string, format, args);
 152   if (ret >= 0)
 153     {
 154       if (ret > 0)
 155         ostream_write_str (stream, temp_string);
 156       free (temp_string);
 157     }
 158   return ret;
 159 }
 160
 161 /* ------------------------- From styled-ostream.h ------------------------- */
 162
 163 typedef ostream_t styled_ostream_t;
 164
 165 #define styled_ostream_write_mem ostream_write_mem
 166 #define styled_ostream_flush ostream_flush
 167 #define styled_ostream_free ostream_free
 168
 169 static inline void
 170 styled_ostream_begin_use_class (styled_ostream_t stream _GL_UNUSED,
 171                                 const char *classname _GL_UNUSED)
 172 {
 173 }
 174
 175 static inline void
 176 styled_ostream_end_use_class (styled_ostream_t stream _GL_UNUSED,
 177                               const char *classname _GL_UNUSED)
 178 {
 179 }
 180
 181 static inline const char *
 182 styled_ostream_get_hyperlink_ref (styled_ostream_t stream _GL_UNUSED)
 183 {
 184   return NULL;
 185 }
 186
 187 static inline const char *
 188 styled_ostream_get_hyperlink_id (styled_ostream_t stream _GL_UNUSED)
 189 {
 190   return NULL;
 191 }
 192
 193 static inline void
 194 styled_ostream_set_hyperlink (styled_ostream_t stream _GL_UNUSED,
 195                               const char *ref _GL_UNUSED,
 196                               const char *id _GL_UNUSED)
 197 {
 198 }
 199
 200 static inline void
 201 styled_ostream_flush_to_current_style (styled_ostream_t stream _GL_UNUSED)
 202 {
 203 }
 204
 205 /* -------------------------- From file-ostream.h -------------------------- */
 206
 207 typedef ostream_t file_ostream_t;
 208
 209 #define file_ostream_write_mem ostream_write_mem
 210 #define file_ostream_flush ostream_flush
 211 #define file_ostream_free ostream_free
 212
 213 static inline file_ostream_t
 214 file_ostream_create (FILE *fp)
 215 {
 216   return fp;
 217 }
 218
 219 /* --------------------------- From fd-ostream.h --------------------------- */
 220
 221 typedef ostream_t fd_ostream_t;
 222
 223 #define fd_ostream_write_mem ostream_write_mem
 224 #define fd_ostream_flush ostream_flush
 225 #define fd_ostream_free ostream_free
 226
 227 static inline fd_ostream_t
 228 fd_ostream_create (int fd, const char *filename _GL_UNUSED,
 229                    bool buffered _GL_UNUSED)
 230 {
 231   if (fd == 1)
 232     return stdout;
 233   else if (fd == 2)
 234     return stderr;
 235   else
 236     return fdopen (fd, "w");
 237 }
 238
 239 /* -------------------------- From term-ostream.h -------------------------- */
 240
 241 typedef int term_color_t;
 242 enum
 243 {
 244   COLOR_DEFAULT = -1  /* unknown */
 245 };
 246
 247 typedef enum
 248 {
 249   WEIGHT_NORMAL = 0,
 250   WEIGHT_BOLD,
 251   WEIGHT_DEFAULT = WEIGHT_NORMAL
 252 } term_weight_t;
 253
 254 typedef enum
 255 {
 256   POSTURE_NORMAL = 0,
 257   POSTURE_ITALIC, /* same as oblique */
 258   POSTURE_DEFAULT = POSTURE_NORMAL
 259 } term_posture_t;
 260
 261 typedef enum
 262 {
 263   UNDERLINE_OFF = 0,
 264   UNDERLINE_ON,
 265   UNDERLINE_DEFAULT = UNDERLINE_OFF
 266 } term_underline_t;
 267
 268 typedef ostream_t term_ostream_t;
 269
 270 #define term_ostream_write_mem ostream_write_mem
 271 #define term_ostream_flush ostream_flush
 272 #define term_ostream_free ostream_free
 273
 274 static inline term_color_t
 275 term_ostream_get_color (term_ostream_t stream _GL_UNUSED)
 276 {
 277   return COLOR_DEFAULT;
 278 }
 279
 280 static inline void
 281 term_ostream_set_color (term_ostream_t stream _GL_UNUSED,
 282                         term_color_t color _GL_UNUSED)
 283 {
 284 }
 285
 286 static inline term_color_t
 287 term_ostream_get_bgcolor (term_ostream_t stream _GL_UNUSED)
 288 {
 289   return COLOR_DEFAULT;
 290 }
 291
 292 static inline void
 293 term_ostream_set_bgcolor (term_ostream_t stream _GL_UNUSED,
 294                           term_color_t color _GL_UNUSED)
 295 {
 296 }
 297
 298 static inline term_weight_t
 299 term_ostream_get_weight (term_ostream_t stream _GL_UNUSED)
 300 {
 301   return WEIGHT_DEFAULT;
 302 }
 303
 304 static inline void
 305 term_ostream_set_weight (term_ostream_t stream _GL_UNUSED,
 306                          term_weight_t weight _GL_UNUSED)
 307 {
 308 }
 309
 310 static inline term_posture_t
 311 term_ostream_get_posture (term_ostream_t stream _GL_UNUSED)
 312 {
 313   return POSTURE_DEFAULT;
 314 }
 315
 316 static inline void
 317 term_ostream_set_posture (term_ostream_t stream _GL_UNUSED,
 318                           term_posture_t posture _GL_UNUSED)
 319 {
 320 }
 321
 322 static inline term_underline_t
 323 term_ostream_get_underline (term_ostream_t stream _GL_UNUSED)
 324 {
 325   return UNDERLINE_DEFAULT;
 326 }
 327
 328 static inline void
 329 term_ostream_set_underline (term_ostream_t stream _GL_UNUSED,
 330                             term_underline_t underline _GL_UNUSED)
 331 {
 332 }
 333
 334 static inline const char *
 335 term_ostream_get_hyperlink_ref (term_ostream_t stream _GL_UNUSED)
 336 {
 337   return NULL;
 338 }
 339
 340 static inline const char *
 341 term_ostream_get_hyperlink_id (term_ostream_t stream _GL_UNUSED)
 342 {
 343   return NULL;
 344 }
 345
 346 static inline void
 347 term_ostream_set_hyperlink (term_ostream_t stream _GL_UNUSED,
 348                             const char *ref _GL_UNUSED,
 349                             const char *id _GL_UNUSED)
 350 {
 351 }
 352
 353 static inline void
 354 term_ostream_flush_to_current_style (term_ostream_t stream)
 355 {
 356   fflush (stream);
 357 }
 358
 359 typedef enum
 360 {
 361   TTYCTL_AUTO = 0,  /* Automatic best-possible choice.  */
 362   TTYCTL_NONE,      /* No control.
 363                        Result: Garbled output can occur, and the terminal can
 364                        be left in any state when the program is interrupted.  */
 365   TTYCTL_PARTIAL,   /* Signal handling.
 366                        Result: Garbled output can occur, but the terminal will
 367                        be left in the default state when the program is
 368                        interrupted.  */
 369   TTYCTL_FULL       /* Signal handling and disabling echo and flush-upon-signal.
 370                        Result: No garbled output, and the the terminal will
 371                        be left in the default state when the program is
 372                        interrupted.  */
 373 } ttyctl_t;
 374
 375 static inline term_ostream_t
 376 term_ostream_create (int fd, const char *filename,
 377                      ttyctl_t tty_control _GL_UNUSED)
 378 {
 379   return fd_ostream_create (fd, filename, true);
 380 }
 381
 382 /* ----------------------- From term-styled-ostream.h ----------------------- */
 383
 384 typedef styled_ostream_t term_styled_ostream_t;
 385
 386 #define term_styled_ostream_write_mem ostream_write_mem
 387 #define term_styled_ostream_flush ostream_flush
 388 #define term_styled_ostream_free ostream_free
 389 #define term_styled_ostream_begin_use_class styled_ostream_begin_use_class
 390 #define term_styled_ostream_end_use_class styled_ostream_end_use_class
 391 #define term_styled_ostream_get_hyperlink_ref styled_ostream_get_hyperlink_ref
 392 #define term_styled_ostream_get_hyperlink_id styled_ostream_get_hyperlink_id
 393 #define term_styled_ostream_set_hyperlink styled_ostream_set_hyperlink
 394 #define term_styled_ostream_flush_to_current_style styled_ostream_flush_to_current_style
 395
 396 static inline term_styled_ostream_t
 397 term_styled_ostream_create (int fd, const char *filename,
 398                             ttyctl_t tty_control _GL_UNUSED,
 399                             const char *css_filename _GL_UNUSED)
 400 {
 401   return fd_ostream_create (fd, filename, true);
 402 }
 403
 404 /* ----------------------- From html-styled-ostream.h ----------------------- */
 405
 406 typedef styled_ostream_t html_styled_ostream_t;
 407
 408 static inline html_styled_ostream_t
 409 html_styled_ostream_create (ostream_t destination _GL_UNUSED,
 410                             const char *css_filename _GL_UNUSED)
 411 {
 412   abort ();
 413   return NULL;
 414 }
 415
 416 /* ------------------------------ From color.h ------------------------------ */
 417
 418 #define color_test_mode false
 419
 420 enum color_option { color_no, color_tty, color_yes, color_html };
 421 #define color_mode color_no
 422
 423 #define style_file_name NULL
 424
 425 static inline bool
 426 handle_color_option (const char *option _GL_UNUSED)
 427 {
 428   return false;
 429 }
 430
 431 static inline void
 432 handle_style_option (const char *option _GL_UNUSED)
 433 {
 434 }
 435
 436 static inline void
 437 print_color_test (void)
 438 {
 439   abort ();
 440 }
 441
 442 static inline void
 443 style_file_prepare (const char *style_file_envvar _GL_UNUSED,
 444                     const char *stylesdir_envvar _GL_UNUSED,
 445                     const char *stylesdir_after_install _GL_UNUSED,
 446                     const char *default_style_file _GL_UNUSED)
 447 {
 448 }
 449
 450 /* ------------------------------ From misc.h ------------------------------ */
 451
 452 static inline styled_ostream_t
 453 styled_ostream_create (int fd, const char *filename,
 454                        ttyctl_t tty_control _GL_UNUSED,
 455                        const char *css_filename _GL_UNUSED)
 456 {
 457   return fd_ostream_create (fd, filename, true);
 458 }
 459
 460 static inline void
 461 libtextstyle_set_failure_exit_code (int exit_code _GL_UNUSED)
 462 {
 463 }
 464
 465 #endif /* _TEXTSTYLE_H */