gdb/ui-file.c

   1 /* UI_FILE - a generic STDIO like output stream.
   2
   3    Copyright (C) 1999-2019 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 /* Implement the ``struct ui_file'' object.  */
  21
  22 #include "defs.h"
  23 #include "ui-file.h"
  24 #include "gdb_obstack.h"
  25 #include "gdb_select.h"
  26 #include "common/filestuff.h"
  27
  28 null_file null_stream;
  29
  30 ui_file::ui_file ()
  31 {}
  32
  33 ui_file::~ui_file ()
  34 {}
  35
  36 void
  37 ui_file::printf (const char *format, ...)
  38 {
  39   va_list args;
  40
  41   va_start (args, format);
  42   vfprintf_unfiltered (this, format, args);
  43   va_end (args);
  44 }
  45
  46 void
  47 ui_file::putstr (const char *str, int quoter)
  48 {
  49   fputstr_unfiltered (str, quoter, this);
  50 }
  51
  52 void
  53 ui_file::putstrn (const char *str, int n, int quoter)
  54 {
  55   fputstrn_unfiltered (str, n, quoter, fputc_unfiltered, this);
  56 }
  57
  58 int
  59 ui_file::putc (int c)
  60 {
  61   return fputc_unfiltered (c, this);
  62 }
  63
  64 void
  65 ui_file::vprintf (const char *format, va_list args)
  66 {
  67   vfprintf_unfiltered (this, format, args);
  68 }
  69
  70 \f
  71
  72 void
  73 null_file::write (const char *buf, long sizeof_buf)
  74 {
  75   /* Discard the request.  */
  76 }
  77
  78 void
  79 null_file::puts (const char *)
  80 {
  81   /* Discard the request.  */
  82 }
  83
  84 void
  85 null_file::write_async_safe (const char *buf, long sizeof_buf)
  86 {
  87   /* Discard the request.  */
  88 }
  89
  90 \f
  91
  92 void
  93 gdb_flush (struct ui_file *file)
  94 {
  95   file->flush ();
  96 }
  97
  98 int
  99 ui_file_isatty (struct ui_file *file)
 100 {
 101   return file->isatty ();
 102 }
 103
 104 /* true if the gdb terminal supports styling, and styling is enabled.  */
 105
 106 static bool
 107 term_cli_styling ()
 108 {
 109   extern int cli_styling;
 110
 111   if (!cli_styling)
 112     return false;
 113
 114   const char *term = getenv ("TERM");
 115   /* Windows doesn't by default define $TERM, but can support styles
 116      regardless.  */
 117 #ifndef _WIN32
 118   if (term == nullptr || !strcmp (term, "dumb"))
 119     return false;
 120 #else
 121   /* But if they do define $TERM, let us behave the same as on Posix
 122      platforms, for the benefit of programs which invoke GDB as their
 123      back-end.  */
 124   if (term && !strcmp (term, "dumb"))
 125     return false;
 126 #endif
 127   return true;
 128 }
 129
 130
 131 void
 132 ui_file_write (struct ui_file *file,
 133                 const char *buf,
 134                 long length_buf)
 135 {
 136   file->write (buf, length_buf);
 137 }
 138
 139 void
 140 ui_file_write_async_safe (struct ui_file *file,
 141                           const char *buf,
 142                           long length_buf)
 143 {
 144   file->write_async_safe (buf, length_buf);
 145 }
 146
 147 long
 148 ui_file_read (struct ui_file *file, char *buf, long length_buf)
 149 {
 150   return file->read (buf, length_buf);
 151 }
 152
 153 void
 154 fputs_unfiltered (const char *buf, struct ui_file *file)
 155 {
 156   file->puts (buf);
 157 }
 158
 159 \f
 160
 161 string_file::~string_file ()
 162 {}
 163
 164 void
 165 string_file::write (const char *buf, long length_buf)
 166 {
 167   m_string.append (buf, length_buf);
 168 }
 169
 170 /* See ui-file.h.  */
 171
 172 bool
 173 string_file::term_out ()
 174 {
 175   return m_term_out;
 176 }
 177
 178 /* See ui-file.h.  */
 179
 180 bool
 181 string_file::can_emit_style_escape ()
 182 {
 183   return m_term_out && term_cli_styling ();
 184 }
 185
 186 \f
 187
 188 stdio_file::stdio_file (FILE *file, bool close_p)
 189 {
 190   set_stream (file);
 191   m_close_p = close_p;
 192 }
 193
 194 stdio_file::stdio_file ()
 195   : m_file (NULL),
 196     m_fd (-1),
 197     m_close_p (false)
 198 {}
 199
 200 stdio_file::~stdio_file ()
 201 {
 202   if (m_close_p)
 203     fclose (m_file);
 204 }
 205
 206 void
 207 stdio_file::set_stream (FILE *file)
 208 {
 209   m_file = file;
 210   m_fd = fileno (file);
 211 }
 212
 213 bool
 214 stdio_file::open (const char *name, const char *mode)
 215 {
 216   /* Close the previous stream, if we own it.  */
 217   if (m_close_p)
 218     {
 219       fclose (m_file);
 220       m_close_p = false;
 221     }
 222
 223   gdb_file_up f = gdb_fopen_cloexec (name, mode);
 224
 225   if (f == NULL)
 226     return false;
 227
 228   set_stream (f.release ());
 229   m_close_p = true;
 230
 231   return true;
 232 }
 233
 234 void
 235 stdio_file::flush ()
 236 {
 237   fflush (m_file);
 238 }
 239
 240 long
 241 stdio_file::read (char *buf, long length_buf)
 242 {
 243   /* Wait until at least one byte of data is available, or we get
 244      interrupted with Control-C.  */
 245   {
 246     fd_set readfds;
 247
 248     FD_ZERO (&readfds);
 249     FD_SET (m_fd, &readfds);
 250     if (interruptible_select (m_fd + 1, &readfds, NULL, NULL, NULL) == -1)
 251       return -1;
 252   }
 253
 254   return ::read (m_fd, buf, length_buf);
 255 }
 256
 257 void
 258 stdio_file::write (const char *buf, long length_buf)
 259 {
 260   /* Calling error crashes when we are called from the exception framework.  */
 261   if (fwrite (buf, length_buf, 1, m_file))
 262     {
 263       /* Nothing.  */
 264     }
 265 }
 266
 267 void
 268 stdio_file::write_async_safe (const char *buf, long length_buf)
 269 {
 270   /* This is written the way it is to avoid a warning from gcc about not using the
 271      result of write (since it can be declared with attribute warn_unused_result).
 272      Alas casting to void doesn't work for this.  */
 273   if (::write (m_fd, buf, length_buf))
 274     {
 275       /* Nothing.  */
 276     }
 277 }
 278
 279 void
 280 stdio_file::puts (const char *linebuffer)
 281 {
 282   /* This host-dependent function (with implementations in
 283      posix-hdep.c and mingw-hdep.c) is given the opportunity to
 284      process the output first in host-dependent way.  If it does, it
 285      should return non-zero, to avoid calling fputs below.  */
 286   if (gdb_console_fputs (linebuffer, m_file))
 287     return;
 288   /* Calling error crashes when we are called from the exception framework.  */
 289   if (fputs (linebuffer, m_file))
 290     {
 291       /* Nothing.  */
 292     }
 293 }
 294
 295 bool
 296 stdio_file::isatty ()
 297 {
 298   return ::isatty (m_fd);
 299 }
 300
 301 /* See ui-file.h.  */
 302
 303 bool
 304 stdio_file::can_emit_style_escape ()
 305 {
 306   return (this == gdb_stdout
 307           && this->isatty ()
 308           && term_cli_styling ());
 309 }
 310
 311 \f
 312
 313 /* This is the implementation of ui_file method 'write' for stderr.
 314    gdb_stdout is flushed before writing to gdb_stderr.  */
 315
 316 void
 317 stderr_file::write (const char *buf, long length_buf)
 318 {
 319   gdb_flush (gdb_stdout);
 320   stdio_file::write (buf, length_buf);
 321 }
 322
 323 /* This is the implementation of ui_file method 'puts' for stderr.
 324    gdb_stdout is flushed before writing to gdb_stderr.  */
 325
 326 void
 327 stderr_file::puts (const char *linebuffer)
 328 {
 329   gdb_flush (gdb_stdout);
 330   stdio_file::puts (linebuffer);
 331 }
 332
 333 stderr_file::stderr_file (FILE *stream)
 334   : stdio_file (stream)
 335 {}
 336
 337 \f
 338
 339 tee_file::tee_file (ui_file *one, bool close_one,
 340                     ui_file *two, bool close_two)
 341   : m_one (one),
 342     m_two (two),
 343     m_close_one (close_one),
 344     m_close_two (close_two)
 345 {}
 346
 347 tee_file::~tee_file ()
 348 {
 349   if (m_close_one)
 350     delete m_one;
 351   if (m_close_two)
 352     delete m_two;
 353 }
 354
 355 void
 356 tee_file::flush ()
 357 {
 358   m_one->flush ();
 359   m_two->flush ();
 360 }
 361
 362 void
 363 tee_file::write (const char *buf, long length_buf)
 364 {
 365   m_one->write (buf, length_buf);
 366   m_two->write (buf, length_buf);
 367 }
 368
 369 void
 370 tee_file::write_async_safe (const char *buf, long length_buf)
 371 {
 372   m_one->write_async_safe (buf, length_buf);
 373   m_two->write_async_safe (buf, length_buf);
 374 }
 375
 376 void
 377 tee_file::puts (const char *linebuffer)
 378 {
 379   m_one->puts (linebuffer);
 380   m_two->puts (linebuffer);
 381 }
 382
 383 bool
 384 tee_file::isatty ()
 385 {
 386   return m_one->isatty ();
 387 }
 388
 389 /* See ui-file.h.  */
 390
 391 bool
 392 tee_file::term_out ()
 393 {
 394   return m_one->term_out ();
 395 }
 396
 397 /* See ui-file.h.  */
 398
 399 bool
 400 tee_file::can_emit_style_escape ()
 401 {
 402   return (this == gdb_stdout
 403           && m_one->term_out ()
 404           && term_cli_styling ());
 405 }