gdb/ui-file.c

   1 /* UI_FILE - a generic STDIO like output stream.
   2
   3    Copyright (C) 1999-2022 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 "gdbsupport/gdb_obstack.h"
  25 #include "gdbsupport/gdb_select.h"
  26 #include "gdbsupport/filestuff.h"
  27 #include "cli-out.h"
  28 #include "cli/cli-style.h"
  29 #include <chrono>
  30
  31 null_file null_stream;
  32
  33 ui_file::ui_file ()
  34 {}
  35
  36 ui_file::~ui_file ()
  37 {}
  38
  39 void
  40 ui_file::printf (const char *format, ...)
  41 {
  42   va_list args;
  43
  44   va_start (args, format);
  45   vprintf (format, args);
  46   va_end (args);
  47 }
  48
  49 void
  50 ui_file::putstr (const char *str, int quoter)
  51 {
  52   while (*str)
  53     printchar (*str++, quoter, false);
  54 }
  55
  56 void
  57 ui_file::putstrn (const char *str, int n, int quoter, bool async_safe)
  58 {
  59   for (int i = 0; i < n; i++)
  60     printchar (str[i], quoter, async_safe);
  61 }
  62
  63 int
  64 ui_file::putc (int c)
  65 {
  66   char copy = (char) c;
  67   write (&copy, 1);
  68   return c;
  69 }
  70
  71 void
  72 ui_file::vprintf (const char *format, va_list args)
  73 {
  74   ui_out_flags flags = disallow_ui_out_field;
  75   cli_ui_out (this, flags).vmessage (m_applied_style, format, args);
  76 }
  77
  78 /* See ui-file.h.  */
  79
  80 void
  81 ui_file::emit_style_escape (const ui_file_style &style)
  82 {
  83   if (can_emit_style_escape () && style != m_applied_style)
  84     {
  85       m_applied_style = style;
  86       this->puts (style.to_ansi ().c_str ());
  87     }
  88 }
  89
  90 /* See ui-file.h.  */
  91
  92 void
  93 ui_file::reset_style ()
  94 {
  95   if (can_emit_style_escape ())
  96     {
  97       m_applied_style = ui_file_style ();
  98       this->puts (m_applied_style.to_ansi ().c_str ());
  99     }
 100 }
 101
 102 /* See ui-file.h.  */
 103
 104 void
 105 ui_file::printchar (int c, int quoter, bool async_safe)
 106 {
 107   char buf[4];
 108   int out = 0;
 109
 110   c &= 0xFF;                    /* Avoid sign bit follies */
 111
 112   if (c < 0x20                   /* Low control chars */
 113       || (c >= 0x7F && c < 0xA0) /* DEL, High controls */
 114       || (sevenbit_strings && c >= 0x80))
 115     {                           /* high order bit set */
 116       buf[out++] = '\\';
 117
 118       switch (c)
 119         {
 120         case '\n':
 121           buf[out++] = 'n';
 122           break;
 123         case '\b':
 124           buf[out++] = 'b';
 125           break;
 126         case '\t':
 127           buf[out++] = 't';
 128           break;
 129         case '\f':
 130           buf[out++] = 'f';
 131           break;
 132         case '\r':
 133           buf[out++] = 'r';
 134           break;
 135         case '\033':
 136           buf[out++] = 'e';
 137           break;
 138         case '\007':
 139           buf[out++] = 'a';
 140           break;
 141         default:
 142           {
 143             buf[out++] = '0' + ((c >> 6) & 0x7);
 144             buf[out++] = '0' + ((c >> 3) & 0x7);
 145             buf[out++] = '0' + ((c >> 0) & 0x7);
 146             break;
 147           }
 148         }
 149     }
 150   else
 151     {
 152       if (quoter != 0 && (c == '\\' || c == quoter))
 153         buf[out++] = '\\';
 154       buf[out++] = c;
 155     }
 156
 157   if (async_safe)
 158     this->write_async_safe (buf, out);
 159   else
 160     this->write (buf, out);
 161 }
 162
 163 \f
 164
 165 void
 166 null_file::write (const char *buf, long sizeof_buf)
 167 {
 168   /* Discard the request.  */
 169 }
 170
 171 void
 172 null_file::puts (const char *)
 173 {
 174   /* Discard the request.  */
 175 }
 176
 177 void
 178 null_file::write_async_safe (const char *buf, long sizeof_buf)
 179 {
 180   /* Discard the request.  */
 181 }
 182
 183 \f
 184
 185 /* true if the gdb terminal supports styling, and styling is enabled.  */
 186
 187 static bool
 188 term_cli_styling ()
 189 {
 190   if (!cli_styling)
 191     return false;
 192
 193   const char *term = getenv ("TERM");
 194   /* Windows doesn't by default define $TERM, but can support styles
 195      regardless.  */
 196 #ifndef _WIN32
 197   if (term == nullptr || !strcmp (term, "dumb"))
 198     return false;
 199 #else
 200   /* But if they do define $TERM, let us behave the same as on Posix
 201      platforms, for the benefit of programs which invoke GDB as their
 202      back-end.  */
 203   if (term && !strcmp (term, "dumb"))
 204     return false;
 205 #endif
 206   return true;
 207 }
 208
 209 \f
 210
 211 string_file::~string_file ()
 212 {}
 213
 214 void
 215 string_file::write (const char *buf, long length_buf)
 216 {
 217   m_string.append (buf, length_buf);
 218 }
 219
 220 /* See ui-file.h.  */
 221
 222 bool
 223 string_file::term_out ()
 224 {
 225   return m_term_out;
 226 }
 227
 228 /* See ui-file.h.  */
 229
 230 bool
 231 string_file::can_emit_style_escape ()
 232 {
 233   return m_term_out && term_cli_styling ();
 234 }
 235
 236 \f
 237
 238 stdio_file::stdio_file (FILE *file, bool close_p)
 239 {
 240   set_stream (file);
 241   m_close_p = close_p;
 242 }
 243
 244 stdio_file::stdio_file ()
 245   : m_file (NULL),
 246     m_fd (-1),
 247     m_close_p (false)
 248 {}
 249
 250 stdio_file::~stdio_file ()
 251 {
 252   if (m_close_p)
 253     fclose (m_file);
 254 }
 255
 256 void
 257 stdio_file::set_stream (FILE *file)
 258 {
 259   m_file = file;
 260   m_fd = fileno (file);
 261 }
 262
 263 bool
 264 stdio_file::open (const char *name, const char *mode)
 265 {
 266   /* Close the previous stream, if we own it.  */
 267   if (m_close_p)
 268     {
 269       fclose (m_file);
 270       m_close_p = false;
 271     }
 272
 273   gdb_file_up f = gdb_fopen_cloexec (name, mode);
 274
 275   if (f == NULL)
 276     return false;
 277
 278   set_stream (f.release ());
 279   m_close_p = true;
 280
 281   return true;
 282 }
 283
 284 void
 285 stdio_file::flush ()
 286 {
 287   fflush (m_file);
 288 }
 289
 290 long
 291 stdio_file::read (char *buf, long length_buf)
 292 {
 293   /* Wait until at least one byte of data is available, or we get
 294      interrupted with Control-C.  */
 295   {
 296     fd_set readfds;
 297
 298     FD_ZERO (&readfds);
 299     FD_SET (m_fd, &readfds);
 300     if (interruptible_select (m_fd + 1, &readfds, NULL, NULL, NULL) == -1)
 301       return -1;
 302   }
 303
 304   return ::read (m_fd, buf, length_buf);
 305 }
 306
 307 void
 308 stdio_file::write (const char *buf, long length_buf)
 309 {
 310   /* Calling error crashes when we are called from the exception framework.  */
 311   if (fwrite (buf, length_buf, 1, m_file))
 312     {
 313       /* Nothing.  */
 314     }
 315 }
 316
 317 void
 318 stdio_file::write_async_safe (const char *buf, long length_buf)
 319 {
 320   /* This is written the way it is to avoid a warning from gcc about not using the
 321      result of write (since it can be declared with attribute warn_unused_result).
 322      Alas casting to void doesn't work for this.  */
 323   if (::write (m_fd, buf, length_buf))
 324     {
 325       /* Nothing.  */
 326     }
 327 }
 328
 329 void
 330 stdio_file::puts (const char *linebuffer)
 331 {
 332   /* This host-dependent function (with implementations in
 333      posix-hdep.c and mingw-hdep.c) is given the opportunity to
 334      process the output first in host-dependent way.  If it does, it
 335      should return non-zero, to avoid calling fputs below.  */
 336   if (gdb_console_fputs (linebuffer, m_file))
 337     return;
 338   /* Calling error crashes when we are called from the exception framework.  */
 339   if (fputs (linebuffer, m_file))
 340     {
 341       /* Nothing.  */
 342     }
 343 }
 344
 345 bool
 346 stdio_file::isatty ()
 347 {
 348   return ::isatty (m_fd);
 349 }
 350
 351 /* See ui-file.h.  */
 352
 353 bool
 354 stdio_file::can_emit_style_escape ()
 355 {
 356   return (this->isatty ()
 357           && term_cli_styling ());
 358 }
 359
 360 \f
 361
 362 /* This is the implementation of ui_file method 'write' for stderr.
 363    gdb_stdout is flushed before writing to gdb_stderr.  */
 364
 365 void
 366 stderr_file::write (const char *buf, long length_buf)
 367 {
 368   gdb_stdout->flush ();
 369   stdio_file::write (buf, length_buf);
 370 }
 371
 372 /* This is the implementation of ui_file method 'puts' for stderr.
 373    gdb_stdout is flushed before writing to gdb_stderr.  */
 374
 375 void
 376 stderr_file::puts (const char *linebuffer)
 377 {
 378   gdb_stdout->flush ();
 379   stdio_file::puts (linebuffer);
 380 }
 381
 382 stderr_file::stderr_file (FILE *stream)
 383   : stdio_file (stream)
 384 {}
 385
 386 \f
 387
 388 tee_file::tee_file (ui_file *one, ui_file_up &&two)
 389   : m_one (one),
 390     m_two (std::move (two))
 391 {}
 392
 393 tee_file::~tee_file ()
 394 {
 395 }
 396
 397 void
 398 tee_file::flush ()
 399 {
 400   m_one->flush ();
 401   m_two->flush ();
 402 }
 403
 404 void
 405 tee_file::write (const char *buf, long length_buf)
 406 {
 407   m_one->write (buf, length_buf);
 408   m_two->write (buf, length_buf);
 409 }
 410
 411 void
 412 tee_file::write_async_safe (const char *buf, long length_buf)
 413 {
 414   m_one->write_async_safe (buf, length_buf);
 415   m_two->write_async_safe (buf, length_buf);
 416 }
 417
 418 void
 419 tee_file::puts (const char *linebuffer)
 420 {
 421   m_one->puts (linebuffer);
 422   m_two->puts (linebuffer);
 423 }
 424
 425 bool
 426 tee_file::isatty ()
 427 {
 428   return m_one->isatty ();
 429 }
 430
 431 /* See ui-file.h.  */
 432
 433 bool
 434 tee_file::term_out ()
 435 {
 436   return m_one->term_out ();
 437 }
 438
 439 /* See ui-file.h.  */
 440
 441 bool
 442 tee_file::can_emit_style_escape ()
 443 {
 444   return (m_one->term_out ()
 445           && term_cli_styling ());
 446 }
 447
 448 /* See ui-file.h.  */
 449
 450 void
 451 no_terminal_escape_file::write (const char *buf, long length_buf)
 452 {
 453   std::string copy (buf, length_buf);
 454   this->puts (copy.c_str ());
 455 }
 456
 457 /* See ui-file.h.  */
 458
 459 void
 460 no_terminal_escape_file::puts (const char *buf)
 461 {
 462   while (*buf != '\0')
 463     {
 464       const char *esc = strchr (buf, '\033');
 465       if (esc == nullptr)
 466         break;
 467
 468       int n_read = 0;
 469       if (!skip_ansi_escape (esc, &n_read))
 470         ++esc;
 471
 472       this->stdio_file::write (buf, esc - buf);
 473       buf = esc + n_read;
 474     }
 475
 476   if (*buf != '\0')
 477     this->stdio_file::write (buf, strlen (buf));
 478 }
 479
 480 void
 481 timestamped_file::write (const char *buf, long len)
 482 {
 483   if (debug_timestamp)
 484     {
 485       /* Print timestamp if previous print ended with a \n.  */
 486       if (m_needs_timestamp)
 487         {
 488           using namespace std::chrono;
 489
 490           steady_clock::time_point now = steady_clock::now ();
 491           seconds s = duration_cast<seconds> (now.time_since_epoch ());
 492           microseconds us = duration_cast<microseconds> (now.time_since_epoch () - s);
 493           std::string timestamp = string_printf ("%ld.%06ld ",
 494                                                  (long) s.count (),
 495                                                  (long) us.count ());
 496           m_stream->puts (timestamp.c_str ());
 497         }
 498
 499       /* Print the message.  */
 500       m_stream->write (buf, len);
 501
 502       m_needs_timestamp = (len > 0 && buf[len - 1] == '\n');
 503     }
 504   else
 505     m_stream->write (buf, len);
 506 }