gdb/ui-out.h

   1 /* Output generating routines for GDB.
   2
   3    Copyright (C) 1999-2024 Free Software Foundation, Inc.
   4
   5    Contributed by Cygnus Solutions.
   6    Written by Fernando Nasser for Cygnus.
   7
   8    This file is part of GDB.
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  22
  23 #ifndef UI_OUT_H
  24 #define UI_OUT_H 1
  25
  26 #include <vector>
  27
  28 #include "gdbsupport/enum-flags.h"
  29 #include "ui-style.h"
  30
  31 class ui_out_level;
  32 class ui_out_table;
  33 struct ui_file;
  34
  35 /* the current ui_out */
  36
  37 /* FIXME: This should not be a global but something passed down from main.c
  38    or top.c.  */
  39 extern struct ui_out **current_ui_current_uiout_ptr (void);
  40 #define current_uiout (*current_ui_current_uiout_ptr ())
  41
  42 /* alignment enum */
  43 enum ui_align
  44   {
  45     ui_left = -1,
  46     ui_center,
  47     ui_right,
  48     ui_noalign
  49   };
  50
  51 /* flags enum */
  52 enum ui_out_flag
  53 {
  54   ui_source_list = (1 << 0),
  55   fix_multi_location_breakpoint_output = (1 << 1),
  56   /* This indicates that %pF should be disallowed in a printf format
  57      string.  */
  58   disallow_ui_out_field = (1 << 2),
  59   fix_breakpoint_script_output = (1 << 3),
  60 };
  61
  62 DEF_ENUM_FLAGS_TYPE (ui_out_flag, ui_out_flags);
  63
  64 /* Prototypes for ui-out API.  */
  65
  66 /* A result is a recursive data structure consisting of lists and
  67    tuples.  */
  68
  69 enum ui_out_type
  70   {
  71     ui_out_type_tuple,
  72     ui_out_type_list
  73   };
  74
  75 /* The possible kinds of fields.  */
  76 enum class field_kind
  77   {
  78     /* "FIELD_STRING" needs a funny name to avoid clashes with tokens
  79        named "STRING".  See PR build/25250.  FIELD_SIGNED is given a
  80        similar name for consistency.  */
  81     FIELD_SIGNED,
  82     FIELD_STRING,
  83   };
  84
  85 /* The base type of all fields that can be emitted using %pF.  */
  86
  87 struct base_field_s
  88 {
  89   const char *name;
  90   field_kind kind;
  91 };
  92
  93 /* A signed integer field, to be passed to %pF in format strings.  */
  94
  95 struct signed_field_s : base_field_s
  96 {
  97   LONGEST val;
  98 };
  99
 100 /* Construct a temporary signed_field_s on the caller's stack and
 101    return a pointer to the constructed object.  We use this because
 102    it's not possible to pass a reference via va_args.  */
 103
 104 static inline signed_field_s *
 105 signed_field (const char *name, LONGEST val,
 106               signed_field_s &&tmp = {})
 107 {
 108   tmp.name = name;
 109   tmp.kind = field_kind::FIELD_SIGNED;
 110   tmp.val = val;
 111   return &tmp;
 112 }
 113
 114 /* A string field, to be passed to %pF in format strings.  */
 115
 116 struct string_field_s : base_field_s
 117 {
 118   const char *str;
 119 };
 120
 121 /* Construct a temporary string_field_s on the caller's stack and
 122    return a pointer to the constructed object.  We use this because
 123    it's not possible to pass a reference via va_args.  */
 124
 125 static inline string_field_s *
 126 string_field (const char *name, const char *str,
 127               string_field_s &&tmp = {})
 128 {
 129   tmp.name = name;
 130   tmp.kind = field_kind::FIELD_STRING;
 131   tmp.str = str;
 132   return &tmp;
 133 }
 134
 135 /* A styled string.  */
 136
 137 struct styled_string_s
 138 {
 139   /* The style.  */
 140   ui_file_style style;
 141
 142   /* The string.  */
 143   const char *str;
 144 };
 145
 146 /* Construct a temporary styled_string_s on the caller's stack and
 147    return a pointer to the constructed object.  We use this because
 148    it's not possible to pass a reference via va_args.  */
 149
 150 static inline styled_string_s *
 151 styled_string (const ui_file_style &style, const char *str,
 152                styled_string_s &&tmp = {})
 153 {
 154   tmp.style = style;
 155   tmp.str = str;
 156   return &tmp;
 157 }
 158
 159 class ui_out
 160 {
 161  public:
 162
 163   explicit ui_out (ui_out_flags flags = 0);
 164   virtual ~ui_out ();
 165
 166   void push_level (ui_out_type type);
 167   void pop_level (ui_out_type type);
 168
 169   /* A table can be considered a special tuple/list combination with the
 170      implied structure: ``table = { hdr = { header, ... } , body = [ {
 171      field, ... }, ... ] }''.  If NR_ROWS is negative then there is at
 172      least one row.  */
 173
 174   void table_begin (int nr_cols, int nr_rows, const std::string &tblid);
 175   void table_header (int width, ui_align align, const std::string &col_name,
 176                      const std::string &col_hdr);
 177   void table_body ();
 178   void table_end ();
 179
 180   void begin (ui_out_type type, const char *id);
 181   void end (ui_out_type type);
 182
 183   void field_signed (const char *fldname, LONGEST value);
 184   void field_fmt_signed (int width, ui_align align, const char *fldname,
 185                          LONGEST value);
 186   /* Like field_signed, but print an unsigned value.  */
 187   void field_unsigned (const char *fldname, ULONGEST value);
 188   void field_core_addr (const char *fldname, struct gdbarch *gdbarch,
 189                         CORE_ADDR address);
 190   void field_string (const char *fldname, const char *string,
 191                      const ui_file_style &style = ui_file_style ());
 192   void field_string (const char *fldname, const std::string &string,
 193                      const ui_file_style &style = ui_file_style ())
 194   {
 195     field_string (fldname, string.c_str (), style);
 196   }
 197   void field_stream (const char *fldname, string_file &stream,
 198                      const ui_file_style &style = ui_file_style ());
 199   void field_skip (const char *fldname);
 200   void field_fmt (const char *fldname, const char *format, ...)
 201     ATTRIBUTE_PRINTF (3, 4);
 202   void field_fmt (const char *fldname, const ui_file_style &style,
 203                   const char *format, ...)
 204     ATTRIBUTE_PRINTF (4, 5);
 205
 206   void spaces (int numspaces);
 207   void text (const char *string);
 208   void text (const std::string &string) { text (string.c_str ()); }
 209
 210   /* Output a printf-style formatted string.  In addition to the usual
 211      printf format specs, this supports a few GDB-specific
 212      formatters:
 213
 214      - '%pF' - output a field.
 215
 216        The argument is a field, wrapped in any of the base_field_s
 217        subclasses.  signed_field for integer fields, string_field for
 218        string fields.  This is preferred over separate
 219        uiout->field_signed(), uiout_>field_string() etc. calls when
 220        the formatted message is translatable.  E.g.:
 221
 222          uiout->message (_("\nWatchpoint %pF deleted because the program has "
 223                          "left the block in\n"
 224                          "which its expression is valid.\n"),
 225                          signed_field ("wpnum", b->number));
 226
 227      - '%p[' - output the following text in a specified style.
 228        '%p]' - output the following text in the default style.
 229
 230        The argument to '%p[' is a ui_file_style pointer.  The argument
 231        to '%p]' must be nullptr.
 232
 233        This is useful when you want to output some portion of a string
 234        literal in some style.  E.g.:
 235
 236          uiout->message (_(" %p[<repeats %u times>%p]"),
 237                          metadata_style.style ().ptr (),
 238                          reps, repeats, nullptr);
 239
 240      - '%ps' - output a styled string.
 241
 242        The argument is the result of a call to styled_string.  This is
 243        useful when you want to output some runtime-generated string in
 244        some style.  E.g.:
 245
 246          uiout->message (_("this is a target address %ps.\n"),
 247                          styled_string (address_style.style (),
 248                                         paddress (gdbarch, pc)));
 249
 250      Note that these all "abuse" the %p printf format spec, in order
 251      to be compatible with GCC's printf format checking.  This is OK
 252      because code in GDB that wants to print a host address should use
 253      host_address_to_string instead of %p.  */
 254   void message (const char *format, ...) ATTRIBUTE_PRINTF (2, 3);
 255   void vmessage (const ui_file_style &in_style,
 256                  const char *format, va_list args) ATTRIBUTE_PRINTF (3, 0);
 257
 258   void wrap_hint (int indent);
 259
 260   void flush ();
 261
 262   /* Redirect the output of a ui_out object temporarily.  */
 263   void redirect (ui_file *outstream);
 264
 265   ui_out_flags test_flags (ui_out_flags mask);
 266
 267   /* HACK: Code in GDB is currently checking to see the type of ui_out
 268      builder when determining which output to produce.  This function is
 269      a hack to encapsulate that test.  Once GDB manages to separate the
 270      CLI/MI from the core of GDB the problem should just go away ....  */
 271
 272   bool is_mi_like_p () const;
 273
 274   bool query_table_field (int colno, int *width, int *alignment,
 275                           const char **col_name);
 276
 277   /* Return true if this stream is prepared to handle style
 278      escapes.  */
 279   virtual bool can_emit_style_escape () const = 0;
 280
 281   /* Return the ui_file currently used for output.  */
 282   virtual ui_file *current_stream () const = 0;
 283
 284   /* An object that starts and finishes displaying progress updates.  */
 285   class progress_update
 286   {
 287   public:
 288     /* Represents the printing state of a progress update.  */
 289     enum state
 290     {
 291       /* Printing will start with the next update.  */
 292       START,
 293       /* Printing has already started.  */
 294       WORKING,
 295       /* Progress bar printing has already started.  */
 296       BAR
 297     };
 298
 299     /* SHOULD_PRINT indicates whether something should be printed for a tty.  */
 300     progress_update ()
 301     {
 302       m_uiout = current_uiout;
 303       m_uiout->do_progress_start ();
 304     }
 305
 306     ~progress_update ()
 307     {
 308       m_uiout->do_progress_end ();
 309     }
 310
 311     progress_update (const progress_update &) = delete;
 312     progress_update &operator= (const progress_update &) = delete;
 313
 314     /* Emit some progress for this progress meter.  Includes current
 315        amount of progress made and total amount in the display.  */
 316     void update_progress (const std::string& msg, const char *unit,
 317                           double cur, double total)
 318     {
 319       m_uiout->do_progress_notify (msg, unit, cur, total);
 320     }
 321
 322     /* Emit some progress for this progress meter.  */
 323     void update_progress (const std::string& msg)
 324     {
 325       m_uiout->do_progress_notify (msg, "", -1, -1);
 326     }
 327
 328   private:
 329
 330     struct ui_out *m_uiout;
 331   };
 332
 333 protected:
 334
 335   virtual void do_table_begin (int nbrofcols, int nr_rows, const char *tblid)
 336     = 0;
 337   virtual void do_table_body () = 0;
 338   virtual void do_table_end () = 0;
 339   virtual void do_table_header (int width, ui_align align,
 340                                 const std::string &col_name,
 341                                 const std::string &col_hdr) = 0;
 342
 343   virtual void do_begin (ui_out_type type, const char *id) = 0;
 344   virtual void do_end (ui_out_type type) = 0;
 345   virtual void do_field_signed (int fldno, int width, ui_align align,
 346                                 const char *fldname, LONGEST value) = 0;
 347   virtual void do_field_unsigned (int fldno, int width, ui_align align,
 348                                   const char *fldname, ULONGEST value) = 0;
 349   virtual void do_field_skip (int fldno, int width, ui_align align,
 350                               const char *fldname) = 0;
 351   virtual void do_field_string (int fldno, int width, ui_align align,
 352                                 const char *fldname, const char *string,
 353                                 const ui_file_style &style) = 0;
 354   virtual void do_field_fmt (int fldno, int width, ui_align align,
 355                              const char *fldname, const ui_file_style &style,
 356                              const char *format, va_list args)
 357     ATTRIBUTE_PRINTF (7, 0) = 0;
 358   virtual void do_spaces (int numspaces) = 0;
 359   virtual void do_text (const char *string) = 0;
 360   virtual void do_message (const ui_file_style &style,
 361                            const char *format, va_list args)
 362     ATTRIBUTE_PRINTF (3,0) = 0;
 363   virtual void do_wrap_hint (int indent) = 0;
 364   virtual void do_flush () = 0;
 365   virtual void do_redirect (struct ui_file *outstream) = 0;
 366
 367   virtual void do_progress_start () = 0;
 368   virtual void do_progress_notify (const std::string &, const char *,
 369                                    double, double) = 0;
 370   virtual void do_progress_end () = 0;
 371
 372   /* Set as not MI-like by default.  It is overridden in subclasses if
 373      necessary.  */
 374
 375   virtual bool do_is_mi_like_p () const
 376   { return false; }
 377
 378  private:
 379   void call_do_message (const ui_file_style &style, const char *format,
 380                         ...);
 381
 382   ui_out_flags m_flags;
 383
 384   /* Vector to store and track the ui-out levels.  */
 385   std::vector<std::unique_ptr<ui_out_level>> m_levels;
 386
 387   /* A table, if any.  At present only a single table is supported.  */
 388   std::unique_ptr<ui_out_table> m_table_up;
 389
 390   void verify_field (int *fldno, int *width, ui_align *align);
 391
 392   int level () const;
 393   ui_out_level *current_level () const;
 394 };
 395
 396 /* Start a new tuple or list on construction, and end it on
 397    destruction.  Normally this is used via the typedefs
 398    ui_out_emit_tuple and ui_out_emit_list.  */
 399 template<ui_out_type Type>
 400 class ui_out_emit_type
 401 {
 402 public:
 403
 404   ui_out_emit_type (struct ui_out *uiout, const char *id)
 405     : m_uiout (uiout)
 406   {
 407     uiout->begin (Type, id);
 408   }
 409
 410   ~ui_out_emit_type ()
 411   {
 412     m_uiout->end (Type);
 413   }
 414
 415   DISABLE_COPY_AND_ASSIGN (ui_out_emit_type);
 416
 417 private:
 418
 419   struct ui_out *m_uiout;
 420 };
 421
 422 typedef ui_out_emit_type<ui_out_type_tuple> ui_out_emit_tuple;
 423 typedef ui_out_emit_type<ui_out_type_list> ui_out_emit_list;
 424
 425 /* Start a new table on construction, and end the table on
 426    destruction.  */
 427 class ui_out_emit_table
 428 {
 429 public:
 430
 431   ui_out_emit_table (struct ui_out *uiout, int nr_cols, int nr_rows,
 432                      const char *tblid)
 433     : m_uiout (uiout)
 434   {
 435     m_uiout->table_begin (nr_cols, nr_rows, tblid);
 436   }
 437
 438   ~ui_out_emit_table ()
 439   {
 440     m_uiout->table_end ();
 441   }
 442
 443   ui_out_emit_table (const ui_out_emit_table &) = delete;
 444   ui_out_emit_table &operator= (const ui_out_emit_table &) = delete;
 445
 446 private:
 447
 448   struct ui_out *m_uiout;
 449 };
 450
 451 /* On construction, redirect a uiout to a given stream.  On
 452    destruction, pop the last redirection by calling the uiout's
 453    redirect method with a NULL parameter.  */
 454 class ui_out_redirect_pop
 455 {
 456 public:
 457
 458   ui_out_redirect_pop (ui_out *uiout, ui_file *stream)
 459     : m_uiout (uiout)
 460   {
 461     m_uiout->redirect (stream);
 462   }
 463
 464   ~ui_out_redirect_pop ()
 465   {
 466     m_uiout->redirect (NULL);
 467   }
 468
 469   ui_out_redirect_pop (const ui_out_redirect_pop &) = delete;
 470   ui_out_redirect_pop &operator= (const ui_out_redirect_pop &) = delete;
 471
 472 private:
 473   struct ui_out *m_uiout;
 474 };
 475
 476 struct buffered_streams;
 477
 478 /* Organizes writes to a collection of buffered output streams
 479    so that when flushed, output is written to all streams in
 480    chronological order.  */
 481
 482 struct buffer_group
 483 {
 484   buffer_group (ui_out *uiout);
 485
 486   /* Flush all buffered writes to the underlying output streams.  */
 487   void flush () const;
 488
 489   /* Record contents of BUF and associate it with STREAM.  */
 490   void write (const char *buf, long length_buf, ui_file *stream);
 491
 492   /* Record a wrap_here and associate it with STREAM.  */
 493   void wrap_here (int indent, ui_file *stream);
 494
 495   /* Record a call to flush and associate it with STREAM.  */
 496   void flush_here (ui_file *stream);
 497
 498 private:
 499
 500   struct output_unit
 501   {
 502     output_unit (std::string msg, int wrap_hint = -1, bool flush = false)
 503       : m_msg (msg), m_wrap_hint (wrap_hint), m_flush (flush)
 504     {}
 505
 506     /* Write contents of this output_unit to the underlying stream.  */
 507     void flush () const;
 508
 509     /* Underlying stream for which this output unit will be written to.  */
 510     ui_file *m_stream;
 511
 512     /* String to be written to underlying buffer.  */
 513     std::string m_msg;
 514
 515     /* Argument to wrap_here.  -1 indicates no wrap.  Used to call wrap_here
 516        during buffer flush.  */
 517     int m_wrap_hint;
 518
 519     /* Indicate that the underlying output stream's flush should be called.  */
 520     bool m_flush;
 521   };
 522
 523   /* Output_units to be written to buffered output streams.  */
 524   std::vector<output_unit> m_buffered_output;
 525
 526   /* Buffered output streams.  */
 527   std::unique_ptr<buffered_streams> m_buffered_streams;
 528 };
 529
 530 /* If FILE is a buffering_file, return it's underlying stream.  */
 531
 532 extern ui_file *get_unbuffered (ui_file *file);
 533
 534 /* Buffer output to gdb_stdout and gdb_stderr for the duration of FUNC.  */
 535
 536 template<typename F, typename... Arg>
 537 void
 538 do_with_buffered_output (F func, ui_out *uiout, Arg... args)
 539 {
 540   buffer_group g (uiout);
 541
 542   try
 543     {
 544       func (uiout, std::forward<Arg> (args)...);
 545     }
 546   catch (gdb_exception &ex)
 547     {
 548       /* Ideally flush would be called in the destructor of buffer_group,
 549          however flushing might cause an exception to be thrown.  Catch it
 550          and ensure the first exception propagates.  */
 551       try
 552         {
 553           g.flush ();
 554         }
 555       catch (const gdb_exception &)
 556         {
 557         }
 558
 559       throw_exception (std::move (ex));
 560     }
 561
 562   /* Try was successful.  Let any further exceptions propagate.  */
 563   g.flush ();
 564 }
 565
 566 /* Accumulate writes to an underlying ui_file.  Output to the
 567    underlying file is deferred until required.  */
 568
 569 struct buffering_file : public ui_file
 570 {
 571   buffering_file (buffer_group *group, ui_file *stream)
 572     : m_group (group),
 573       m_stream (stream)
 574   { /* Nothing.  */ }
 575
 576   /* Return the underlying output stream.  */
 577   ui_file *stream () const
 578   {
 579     return m_stream;
 580   }
 581
 582   /* Record the contents of BUF.  */
 583   void write (const char *buf, long length_buf) override
 584   {
 585     m_group->write (buf, length_buf, m_stream);
 586   }
 587
 588   /* Record a wrap_here call with argument INDENT.  */
 589   void wrap_here (int indent) override
 590   {
 591     m_group->wrap_here (indent, m_stream);
 592   }
 593
 594   /* Return true if the underlying stream is a tty.  */
 595   bool isatty () override
 596   {
 597     return m_stream->isatty ();
 598   }
 599
 600   /* Return true if ANSI escapes can be used on the underlying stream.  */
 601   bool can_emit_style_escape () override
 602   {
 603     return m_stream->can_emit_style_escape ();
 604   }
 605
 606   /* Flush the underlying output stream.  */
 607   void flush () override
 608   {
 609     return m_group->flush_here (m_stream);
 610   }
 611
 612 private:
 613
 614   /* Coordinates buffering across multiple buffering_files.  */
 615   buffer_group *m_group;
 616
 617   /* The underlying output stream.  */
 618   ui_file *m_stream;
 619 };
 620
 621 /* Attaches and detaches buffers for each of the gdb_std* streams.  */
 622
 623 struct buffered_streams
 624 {
 625   buffered_streams (buffer_group *group, ui_out *uiout);
 626
 627   ~buffered_streams ()
 628   {
 629     this->remove_buffers ();
 630   }
 631
 632   /* Remove buffering_files from all underlying streams.  */
 633   void remove_buffers ();
 634
 635 private:
 636
 637   /* True if buffers are still attached to each underlying output stream.  */
 638   bool m_buffers_in_place;
 639
 640   /* Buffers for each gdb_std* output stream.  */
 641   buffering_file m_buffered_stdout;
 642   buffering_file m_buffered_stderr;
 643   buffering_file m_buffered_stdlog;
 644   buffering_file m_buffered_stdtarg;
 645   buffering_file m_buffered_stdtargerr;
 646
 647   /* Buffer for current_uiout's output stream.  */
 648   std::optional<buffering_file> m_buffered_current_uiout;
 649
 650   /* Additional ui_out being buffered.  */
 651   ui_out *m_uiout;
 652
 653   /* Buffer for m_uiout's output stream.  */
 654   std::optional<buffering_file> m_buffered_uiout;
 655 };
 656
 657 #endif /* UI_OUT_H */