1 /* UI_FILE - a generic STDIO like output stream.
2 
3    Copyright (C) 1999-2024 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 "ui-file.h"
23 #include "gdbsupport/gdb_obstack.h"
24 #include "gdbsupport/gdb_select.h"
25 #include "gdbsupport/filestuff.h"
26 #include "cli-out.h"
27 #include "cli/cli-style.h"
28 #include <chrono>
29 
30 null_file null_stream;
31 
ui_file()32 ui_file::ui_file ()
33 {}
34 
~ui_file()35 ui_file::~ui_file ()
36 {}
37 
38 void
printf(const char * format,...)39 ui_file::printf (const char *format, ...)
40 {
41   va_list args;
42 
43   va_start (args, format);
44   vprintf (format, args);
45   va_end (args);
46 }
47 
48 void
putstr(const char * str,int quoter)49 ui_file::putstr (const char *str, int quoter)
50 {
51   while (*str)
52     printchar (*str++, quoter, false);
53 }
54 
55 void
putstrn(const char * str,int n,int quoter,bool async_safe)56 ui_file::putstrn (const char *str, int n, int quoter, bool async_safe)
57 {
58   for (int i = 0; i < n; i++)
59     printchar (str[i], quoter, async_safe);
60 }
61 
62 void
putc(int c)63 ui_file::putc (int c)
64 {
65   char copy = (char) c;
66   write (&copy, 1);
67 }
68 
69 void
vprintf(const char * format,va_list args)70 ui_file::vprintf (const char *format, va_list args)
71 {
72   ui_out_flags flags = disallow_ui_out_field;
73   cli_ui_out (this, flags).vmessage (m_applied_style, format, args);
74 }
75 
76 /* See ui-file.h.  */
77 
78 void
emit_style_escape(const ui_file_style & style)79 ui_file::emit_style_escape (const ui_file_style &style)
80 {
81   if (can_emit_style_escape () && style != m_applied_style)
82     {
83       m_applied_style = style;
84       this->puts (style.to_ansi ().c_str ());
85     }
86 }
87 
88 /* See ui-file.h.  */
89 
90 void
reset_style()91 ui_file::reset_style ()
92 {
93   if (can_emit_style_escape ())
94     {
95       m_applied_style = ui_file_style ();
96       this->puts (m_applied_style.to_ansi ().c_str ());
97     }
98 }
99 
100 /* See ui-file.h.  */
101 
102 void
printchar(int c,int quoter,bool async_safe)103 ui_file::printchar (int c, int quoter, bool async_safe)
104 {
105   char buf[4];
106   int out = 0;
107 
108   c &= 0xFF;                            /* Avoid sign bit follies */
109 
110   if (c < 0x20                           /* Low control chars */
111       || (c >= 0x7F && c < 0xA0) /* DEL, High controls */
112       || (sevenbit_strings && c >= 0x80))
113     {                                   /* high order bit set */
114       buf[out++] = '\\';
115 
116       switch (c)
117           {
118           case '\n':
119             buf[out++] = 'n';
120             break;
121           case '\b':
122             buf[out++] = 'b';
123             break;
124           case '\t':
125             buf[out++] = 't';
126             break;
127           case '\f':
128             buf[out++] = 'f';
129             break;
130           case '\r':
131             buf[out++] = 'r';
132             break;
133           case '\033':
134             buf[out++] = 'e';
135             break;
136           case '\007':
137             buf[out++] = 'a';
138             break;
139           default:
140             {
141               buf[out++] = '0' + ((c >> 6) & 0x7);
142               buf[out++] = '0' + ((c >> 3) & 0x7);
143               buf[out++] = '0' + ((c >> 0) & 0x7);
144               break;
145             }
146           }
147     }
148   else
149     {
150       if (quoter != 0 && (c == '\\' || c == quoter))
151           buf[out++] = '\\';
152       buf[out++] = c;
153     }
154 
155   if (async_safe)
156     this->write_async_safe (buf, out);
157   else
158     this->write (buf, out);
159 }
160 
161 
162 
163 void
write(const char * buf,long sizeof_buf)164 null_file::write (const char *buf, long sizeof_buf)
165 {
166   /* Discard the request.  */
167 }
168 
169 void
puts(const char *)170 null_file::puts (const char *)
171 {
172   /* Discard the request.  */
173 }
174 
175 void
write_async_safe(const char * buf,long sizeof_buf)176 null_file::write_async_safe (const char *buf, long sizeof_buf)
177 {
178   /* Discard the request.  */
179 }
180 
181 
182 
183 /* true if the gdb terminal supports styling, and styling is enabled.  */
184 
185 static bool
term_cli_styling()186 term_cli_styling ()
187 {
188   if (!cli_styling)
189     return false;
190 
191   const char *term = getenv ("TERM");
192   /* Windows doesn't by default define $TERM, but can support styles
193      regardless.  */
194 #ifndef _WIN32
195   if (term == nullptr || !strcmp (term, "dumb"))
196     return false;
197 #else
198   /* But if they do define $TERM, let us behave the same as on Posix
199      platforms, for the benefit of programs which invoke GDB as their
200      back-end.  */
201   if (term && !strcmp (term, "dumb"))
202     return false;
203 #endif
204   return true;
205 }
206 
207 
208 
~string_file()209 string_file::~string_file ()
210 {}
211 
212 void
write(const char * buf,long length_buf)213 string_file::write (const char *buf, long length_buf)
214 {
215   m_string.append (buf, length_buf);
216 }
217 
218 /* See ui-file.h.  */
219 
220 bool
term_out()221 string_file::term_out ()
222 {
223   return m_term_out;
224 }
225 
226 /* See ui-file.h.  */
227 
228 bool
can_emit_style_escape()229 string_file::can_emit_style_escape ()
230 {
231   return m_term_out && term_cli_styling ();
232 }
233 
234 
235 
stdio_file(FILE * file,bool close_p)236 stdio_file::stdio_file (FILE *file, bool close_p)
237 {
238   set_stream (file);
239   m_close_p = close_p;
240 }
241 
stdio_file()242 stdio_file::stdio_file ()
243   : m_file (NULL),
244     m_fd (-1),
245     m_close_p (false)
246 {}
247 
~stdio_file()248 stdio_file::~stdio_file ()
249 {
250   if (m_close_p)
251     fclose (m_file);
252 }
253 
254 void
set_stream(FILE * file)255 stdio_file::set_stream (FILE *file)
256 {
257   m_file = file;
258   m_fd = fileno (file);
259 }
260 
261 bool
open(const char * name,const char * mode)262 stdio_file::open (const char *name, const char *mode)
263 {
264   /* Close the previous stream, if we own it.  */
265   if (m_close_p)
266     {
267       fclose (m_file);
268       m_close_p = false;
269     }
270 
271   gdb_file_up f = gdb_fopen_cloexec (name, mode);
272 
273   if (f == NULL)
274     return false;
275 
276   set_stream (f.release ());
277   m_close_p = true;
278 
279   return true;
280 }
281 
282 void
flush()283 stdio_file::flush ()
284 {
285   fflush (m_file);
286 }
287 
288 long
read(char * buf,long length_buf)289 stdio_file::read (char *buf, long length_buf)
290 {
291   /* Wait until at least one byte of data is available, or we get
292      interrupted with Control-C.  */
293   {
294     fd_set readfds;
295 
296     FD_ZERO (&readfds);
297     FD_SET (m_fd, &readfds);
298     if (interruptible_select (m_fd + 1, &readfds, NULL, NULL, NULL) == -1)
299       return -1;
300   }
301 
302   return ::read (m_fd, buf, length_buf);
303 }
304 
305 void
write(const char * buf,long length_buf)306 stdio_file::write (const char *buf, long length_buf)
307 {
308   /* Calling error crashes when we are called from the exception framework.  */
309   if (fwrite (buf, length_buf, 1, m_file))
310     {
311       /* Nothing.  */
312     }
313 }
314 
315 void
write_async_safe(const char * buf,long length_buf)316 stdio_file::write_async_safe (const char *buf, long length_buf)
317 {
318   /* This is written the way it is to avoid a warning from gcc about not using the
319      result of write (since it can be declared with attribute warn_unused_result).
320      Alas casting to void doesn't work for this.  */
321   if (::write (m_fd, buf, length_buf))
322     {
323       /* Nothing.  */
324     }
325 }
326 
327 void
puts(const char * linebuffer)328 stdio_file::puts (const char *linebuffer)
329 {
330   /* This host-dependent function (with implementations in
331      posix-hdep.c and mingw-hdep.c) is given the opportunity to
332      process the output first in host-dependent way.  If it does, it
333      should return non-zero, to avoid calling fputs below.  */
334   if (gdb_console_fputs (linebuffer, m_file))
335     return;
336   /* Calling error crashes when we are called from the exception framework.  */
337   if (fputs (linebuffer, m_file))
338     {
339       /* Nothing.  */
340     }
341 }
342 
343 bool
isatty()344 stdio_file::isatty ()
345 {
346   return ::isatty (m_fd);
347 }
348 
349 /* See ui-file.h.  */
350 
351 bool
can_emit_style_escape()352 stdio_file::can_emit_style_escape ()
353 {
354   return (this->isatty ()
355             && term_cli_styling ());
356 }
357 
358 
359 
360 /* This is the implementation of ui_file method 'write' for stderr.
361    gdb_stdout is flushed before writing to gdb_stderr.  */
362 
363 void
write(const char * buf,long length_buf)364 stderr_file::write (const char *buf, long length_buf)
365 {
366   gdb_stdout->flush ();
367   stdio_file::write (buf, length_buf);
368 }
369 
370 /* This is the implementation of ui_file method 'puts' for stderr.
371    gdb_stdout is flushed before writing to gdb_stderr.  */
372 
373 void
puts(const char * linebuffer)374 stderr_file::puts (const char *linebuffer)
375 {
376   gdb_stdout->flush ();
377   stdio_file::puts (linebuffer);
378 }
379 
stderr_file(FILE * stream)380 stderr_file::stderr_file (FILE *stream)
381   : stdio_file (stream)
382 {}
383 
384 
385 
tee_file(ui_file * one,ui_file * two)386 tee_file::tee_file (ui_file *one, ui_file *two)
387   : m_one (one),
388     m_two (two)
389 {}
390 
~tee_file()391 tee_file::~tee_file ()
392 {
393 }
394 
395 void
flush()396 tee_file::flush ()
397 {
398   m_one->flush ();
399   m_two->flush ();
400 }
401 
402 void
write(const char * buf,long length_buf)403 tee_file::write (const char *buf, long length_buf)
404 {
405   m_one->write (buf, length_buf);
406   m_two->write (buf, length_buf);
407 }
408 
409 void
write_async_safe(const char * buf,long length_buf)410 tee_file::write_async_safe (const char *buf, long length_buf)
411 {
412   m_one->write_async_safe (buf, length_buf);
413   m_two->write_async_safe (buf, length_buf);
414 }
415 
416 void
puts(const char * linebuffer)417 tee_file::puts (const char *linebuffer)
418 {
419   m_one->puts (linebuffer);
420   m_two->puts (linebuffer);
421 }
422 
423 bool
isatty()424 tee_file::isatty ()
425 {
426   return m_one->isatty ();
427 }
428 
429 /* See ui-file.h.  */
430 
431 bool
term_out()432 tee_file::term_out ()
433 {
434   return m_one->term_out ();
435 }
436 
437 /* See ui-file.h.  */
438 
439 bool
can_emit_style_escape()440 tee_file::can_emit_style_escape ()
441 {
442   return (m_one->term_out ()
443             && term_cli_styling ());
444 }
445 
446 /* See ui-file.h.  */
447 
448 void
write(const char * buf,long length_buf)449 no_terminal_escape_file::write (const char *buf, long length_buf)
450 {
451   std::string copy (buf, length_buf);
452   this->puts (copy.c_str ());
453 }
454 
455 /* See ui-file.h.  */
456 
457 void
puts(const char * buf)458 no_terminal_escape_file::puts (const char *buf)
459 {
460   while (*buf != '\0')
461     {
462       const char *esc = strchr (buf, '\033');
463       if (esc == nullptr)
464           break;
465 
466       int n_read = 0;
467       if (!skip_ansi_escape (esc, &n_read))
468           ++esc;
469 
470       this->stdio_file::write (buf, esc - buf);
471       buf = esc + n_read;
472     }
473 
474   if (*buf != '\0')
475     this->stdio_file::write (buf, strlen (buf));
476 }
477 
478 void
write(const char * buf,long len)479 timestamped_file::write (const char *buf, long len)
480 {
481   if (debug_timestamp)
482     {
483       /* Print timestamp if previous print ended with a \n.  */
484       if (m_needs_timestamp)
485           {
486             using namespace std::chrono;
487 
488             steady_clock::time_point now = steady_clock::now ();
489             seconds s = duration_cast<seconds> (now.time_since_epoch ());
490             microseconds us = duration_cast<microseconds> (now.time_since_epoch () - s);
491             std::string timestamp = string_printf ("%ld.%06ld ",
492                                                              (long) s.count (),
493                                                              (long) us.count ());
494             m_stream->puts (timestamp.c_str ());
495           }
496 
497       /* Print the message.  */
498       m_stream->write (buf, len);
499 
500       m_needs_timestamp = (len > 0 && buf[len - 1] == '\n');
501     }
502   else
503     m_stream->write (buf, len);
504 }
505