gdb/ui-file.c

   1 /* UI_FILE - a generic STDIO like output stream.
   2
   3    Copyright (C) 1999-2021 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 "gdbsupport/gdb_select.h"
  26 #include "gdbsupport/filestuff.h"
  27 #include "cli/cli-style.h"
  28
  29 null_file null_stream;
  30
  31 ui_file::ui_file ()
  32 {}
  33
  34 ui_file::~ui_file ()
  35 {}
  36
  37 void
  38 ui_file::printf (const char *format, ...)
  39 {
  40   va_list args;
  41
  42   va_start (args, format);
  43   vfprintf_unfiltered (this, format, args);
  44   va_end (args);
  45 }
  46
  47 void
  48 ui_file::putstr (const char *str, int quoter)
  49 {
  50   fputstr_unfiltered (str, quoter, this);
  51 }
  52
  53 void
  54 ui_file::putstrn (const char *str, int n, int quoter)
  55 {
  56   fputstrn_unfiltered (str, n, quoter, fputc_unfiltered, this);
  57 }
  58
  59 int
  60 ui_file::putc (int c)
  61 {
  62   return fputc_unfiltered (c, this);
  63 }
  64
  65 void
  66 ui_file::vprintf (const char *format, va_list args)
  67 {
  68   vfprintf_unfiltered (this, format, args);
  69 }
  70
  71 \f
  72
  73 void
  74 null_file::write (const char *buf, long sizeof_buf)
  75 {
  76   /* Discard the request.  */
  77 }
  78
  79 void
  80 null_file::puts (const char *)
  81 {
  82   /* Discard the request.  */
  83 }
  84
  85 void
  86 null_file::write_async_safe (const char *buf, long sizeof_buf)
  87 {
  88   /* Discard the request.  */
  89 }
  90
  91 \f
  92
  93 /* true if the gdb terminal supports styling, and styling is enabled.  */
  94
  95 static bool
  96 term_cli_styling ()
  97 {
  98   if (!cli_styling)
  99     return false;
 100
 101   const char *term = getenv ("TERM");
 102   /* Windows doesn't by default define $TERM, but can support styles
 103      regardless.  */
 104 #ifndef _WIN32
 105   if (term == nullptr || !strcmp (term, "dumb"))
 106     return false;
 107 #else
 108   /* But if they do define $TERM, let us behave the same as on Posix
 109      platforms, for the benefit of programs which invoke GDB as their
 110      back-end.  */
 111   if (term && !strcmp (term, "dumb"))
 112     return false;
 113 #endif
 114   return true;
 115 }
 116
 117 \f
 118
 119 string_file::~string_file ()
 120 {}
 121
 122 void
 123 string_file::write (const char *buf, long length_buf)
 124 {
 125   m_string.append (buf, length_buf);
 126 }
 127
 128 /* See ui-file.h.  */
 129
 130 bool
 131 string_file::term_out ()
 132 {
 133   return m_term_out;
 134 }
 135
 136 /* See ui-file.h.  */
 137
 138 bool
 139 string_file::can_emit_style_escape ()
 140 {
 141   return m_term_out && term_cli_styling ();
 142 }
 143
 144 \f
 145
 146 stdio_file::stdio_file (FILE *file, bool close_p)
 147 {
 148   set_stream (file);
 149   m_close_p = close_p;
 150 }
 151
 152 stdio_file::stdio_file ()
 153   : m_file (NULL),
 154     m_fd (-1),
 155     m_close_p (false)
 156 {}
 157
 158 stdio_file::~stdio_file ()
 159 {
 160   if (m_close_p)
 161     fclose (m_file);
 162 }
 163
 164 void
 165 stdio_file::set_stream (FILE *file)
 166 {
 167   m_file = file;
 168   m_fd = fileno (file);
 169 }
 170
 171 bool
 172 stdio_file::open (const char *name, const char *mode)
 173 {
 174   /* Close the previous stream, if we own it.  */
 175   if (m_close_p)
 176     {
 177       fclose (m_file);
 178       m_close_p = false;
 179     }
 180
 181   gdb_file_up f = gdb_fopen_cloexec (name, mode);
 182
 183   if (f == NULL)
 184     return false;
 185
 186   set_stream (f.release ());
 187   m_close_p = true;
 188
 189   return true;
 190 }
 191
 192 void
 193 stdio_file::flush ()
 194 {
 195   fflush (m_file);
 196 }
 197
 198 long
 199 stdio_file::read (char *buf, long length_buf)
 200 {
 201   /* Wait until at least one byte of data is available, or we get
 202      interrupted with Control-C.  */
 203   {
 204     fd_set readfds;
 205
 206     FD_ZERO (&readfds);
 207     FD_SET (m_fd, &readfds);
 208     if (interruptible_select (m_fd + 1, &readfds, NULL, NULL, NULL) == -1)
 209       return -1;
 210   }
 211
 212   return ::read (m_fd, buf, length_buf);
 213 }
 214
 215 void
 216 stdio_file::write (const char *buf, long length_buf)
 217 {
 218   /* Calling error crashes when we are called from the exception framework.  */
 219   if (fwrite (buf, length_buf, 1, m_file))
 220     {
 221       /* Nothing.  */
 222     }
 223 }
 224
 225 void
 226 stdio_file::write_async_safe (const char *buf, long length_buf)
 227 {
 228   /* This is written the way it is to avoid a warning from gcc about not using the
 229      result of write (since it can be declared with attribute warn_unused_result).
 230      Alas casting to void doesn't work for this.  */
 231   if (::write (m_fd, buf, length_buf))
 232     {
 233       /* Nothing.  */
 234     }
 235 }
 236
 237 void
 238 stdio_file::puts (const char *linebuffer)
 239 {
 240   /* This host-dependent function (with implementations in
 241      posix-hdep.c and mingw-hdep.c) is given the opportunity to
 242      process the output first in host-dependent way.  If it does, it
 243      should return non-zero, to avoid calling fputs below.  */
 244   if (gdb_console_fputs (linebuffer, m_file))
 245     return;
 246   /* Calling error crashes when we are called from the exception framework.  */
 247   if (fputs (linebuffer, m_file))
 248     {
 249       /* Nothing.  */
 250     }
 251 }
 252
 253 bool
 254 stdio_file::isatty ()
 255 {
 256   return ::isatty (m_fd);
 257 }
 258
 259 /* See ui-file.h.  */
 260
 261 bool
 262 stdio_file::can_emit_style_escape ()
 263 {
 264   return ((this == gdb_stdout || this == gdb_stderr)
 265           && this->isatty ()
 266           && term_cli_styling ());
 267 }
 268
 269 \f
 270
 271 /* This is the implementation of ui_file method 'write' for stderr.
 272    gdb_stdout is flushed before writing to gdb_stderr.  */
 273
 274 void
 275 stderr_file::write (const char *buf, long length_buf)
 276 {
 277   gdb_stdout->flush ();
 278   stdio_file::write (buf, length_buf);
 279 }
 280
 281 /* This is the implementation of ui_file method 'puts' for stderr.
 282    gdb_stdout is flushed before writing to gdb_stderr.  */
 283
 284 void
 285 stderr_file::puts (const char *linebuffer)
 286 {
 287   gdb_stdout->flush ();
 288   stdio_file::puts (linebuffer);
 289 }
 290
 291 stderr_file::stderr_file (FILE *stream)
 292   : stdio_file (stream)
 293 {}
 294
 295 \f
 296
 297 tee_file::tee_file (ui_file *one, ui_file_up &&two)
 298   : m_one (one),
 299     m_two (std::move (two))
 300 {}
 301
 302 tee_file::~tee_file ()
 303 {
 304 }
 305
 306 void
 307 tee_file::flush ()
 308 {
 309   m_one->flush ();
 310   m_two->flush ();
 311 }
 312
 313 void
 314 tee_file::write (const char *buf, long length_buf)
 315 {
 316   m_one->write (buf, length_buf);
 317   m_two->write (buf, length_buf);
 318 }
 319
 320 void
 321 tee_file::write_async_safe (const char *buf, long length_buf)
 322 {
 323   m_one->write_async_safe (buf, length_buf);
 324   m_two->write_async_safe (buf, length_buf);
 325 }
 326
 327 void
 328 tee_file::puts (const char *linebuffer)
 329 {
 330   m_one->puts (linebuffer);
 331   m_two->puts (linebuffer);
 332 }
 333
 334 bool
 335 tee_file::isatty ()
 336 {
 337   return m_one->isatty ();
 338 }
 339
 340 /* See ui-file.h.  */
 341
 342 bool
 343 tee_file::term_out ()
 344 {
 345   return m_one->term_out ();
 346 }
 347
 348 /* See ui-file.h.  */
 349
 350 bool
 351 tee_file::can_emit_style_escape ()
 352 {
 353   return ((this == gdb_stdout || this == gdb_stderr)
 354           && m_one->term_out ()
 355           && term_cli_styling ());
 356 }
 357
 358 /* See ui-file.h.  */
 359
 360 void
 361 no_terminal_escape_file::write (const char *buf, long length_buf)
 362 {
 363   std::string copy (buf, length_buf);
 364   this->puts (copy.c_str ());
 365 }
 366
 367 /* See ui-file.h.  */
 368
 369 void
 370 no_terminal_escape_file::puts (const char *buf)
 371 {
 372   while (*buf != '\0')
 373     {
 374       const char *esc = strchr (buf, '\033');
 375       if (esc == nullptr)
 376         break;
 377
 378       int n_read = 0;
 379       if (!skip_ansi_escape (esc, &n_read))
 380         ++esc;
 381
 382       this->stdio_file::write (buf, esc - buf);
 383       buf = esc + n_read;
 384     }
 385
 386   if (*buf != '\0')
 387     this->stdio_file::write (buf, strlen (buf));
 388 }