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