gdb/ui-out.h

   1 /* Output generating routines for GDB.
   2
   3    Copyright (C) 1999-2019 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   /* For CLI output, this flag is set if unfiltered output is desired.
  57      This should only be used by low-level formatting functions.  */
  58   unfiltered_output = (1 << 2),
  59   /* This indicates that %pF should be disallowed in a printf format
  60      string.  */
  61   disallow_ui_out_field = (1 << 3)
  62 };
  63
  64 DEF_ENUM_FLAGS_TYPE (ui_out_flag, ui_out_flags);
  65
  66 /* Prototypes for ui-out API.  */
  67
  68 /* A result is a recursive data structure consisting of lists and
  69    tuples.  */
  70
  71 enum ui_out_type
  72   {
  73     ui_out_type_tuple,
  74     ui_out_type_list
  75   };
  76
  77 /* The possible kinds of fields.  */
  78 enum class field_kind
  79   {
  80     /* "FIELD_STRING" needs has a funny name to avoid clashes with
  81        tokens named "STRING".  See PR build/25250.  FIELD_SIGNED is
  82        given a similar name for consistency.  */
  83     FIELD_SIGNED,
  84     FIELD_STRING,
  85   };
  86
  87 /* The base type of all fields that can be emitted using %pF.  */
  88
  89 struct base_field_s
  90 {
  91   const char *name;
  92   field_kind kind;
  93 };
  94
  95 /* A signed integer field, to be passed to %pF in format strings.  */
  96
  97 struct signed_field_s : base_field_s
  98 {
  99   LONGEST val;
 100 };
 101
 102 /* Construct a temporary signed_field_s on the caller's stack and
 103    return a pointer to the constructed object.  We use this because
 104    it's not possible to pass a reference via va_args.  */
 105
 106 static inline signed_field_s *
 107 signed_field (const char *name, LONGEST val,
 108               signed_field_s &&tmp = {})
 109 {
 110   tmp.name = name;
 111   tmp.kind = field_kind::FIELD_SIGNED;
 112   tmp.val = val;
 113   return &tmp;
 114 }
 115
 116 /* A string field, to be passed to %pF in format strings.  */
 117
 118 struct string_field_s : base_field_s
 119 {
 120   const char *str;
 121 };
 122
 123 /* Construct a temporary string_field_s on the caller's stack and
 124    return a pointer to the constructed object.  We use this because
 125    it's not possible to pass a reference via va_args.  */
 126
 127 static inline string_field_s *
 128 string_field (const char *name, const char *str,
 129               string_field_s &&tmp = {})
 130 {
 131   tmp.name = name;
 132   tmp.kind = field_kind::FIELD_STRING;
 133   tmp.str = str;
 134   return &tmp;
 135 }
 136
 137 /* A styled string.  */
 138
 139 struct styled_string_s
 140 {
 141   /* The style.  */
 142   ui_file_style style;
 143
 144   /* The string.  */
 145   const char *str;
 146 };
 147
 148 /* Construct a temporary styled_string_s on the caller's stack and
 149    return a pointer to the constructed object.  We use this because
 150    it's not possible to pass a reference via va_args.  */
 151
 152 static inline styled_string_s *
 153 styled_string (const ui_file_style &style, const char *str,
 154                styled_string_s &&tmp = {})
 155 {
 156   tmp.style = style;
 157   tmp.str = str;
 158   return &tmp;
 159 }
 160
 161 class ui_out
 162 {
 163  public:
 164
 165   explicit ui_out (ui_out_flags flags = 0);
 166   virtual ~ui_out ();
 167
 168   void push_level (ui_out_type type);
 169   void pop_level (ui_out_type type);
 170
 171   /* A table can be considered a special tuple/list combination with the
 172      implied structure: ``table = { hdr = { header, ... } , body = [ {
 173      field, ... }, ... ] }''.  If NR_ROWS is negative then there is at
 174      least one row.  */
 175
 176   void table_begin (int nr_cols, int nr_rows, const std::string &tblid);
 177   void table_header (int width, ui_align align, const std::string &col_name,
 178                      const std::string &col_hdr);
 179   void table_body ();
 180   void table_end ();
 181
 182   void begin (ui_out_type type, const char *id);
 183   void end (ui_out_type type);
 184
 185   void field_signed (const char *fldname, LONGEST value);
 186   void field_fmt_signed (int width, ui_align align, const char *fldname,
 187                          LONGEST value);
 188   /* Like field_signed, but print an unsigned value.  */
 189   void field_unsigned (const char *fldname, ULONGEST value);
 190   void field_core_addr (const char *fldname, struct gdbarch *gdbarch,
 191                         CORE_ADDR address);
 192   void field_string (const char *fldname, const char *string,
 193                      const ui_file_style &style = ui_file_style ());
 194   void field_string (const char *fldname, const std::string &string);
 195   void field_stream (const char *fldname, string_file &stream,
 196                      const ui_file_style &style = ui_file_style ());
 197   void field_skip (const char *fldname);
 198   void field_fmt (const char *fldname, const char *format, ...)
 199     ATTRIBUTE_PRINTF (3, 4);
 200   void field_fmt (const char *fldname, const ui_file_style &style,
 201                   const char *format, ...)
 202     ATTRIBUTE_PRINTF (4, 5);
 203
 204   void spaces (int numspaces);
 205   void text (const char *string);
 206
 207   /* Output a printf-style formatted string.  In addition to the usual
 208      printf format specs, this supports a few GDB-specific
 209      formatters:
 210
 211      - '%pF' - output a field.
 212
 213        The argument is a field, wrapped in any of the base_field_s
 214        subclasses.  signed_field for integer fields, string_field for
 215        string fields.  This is preferred over separate
 216        uiout->field_signed(), uiout_>field_string() etc. calls when
 217        the formatted message is translatable.  E.g.:
 218
 219          uiout->message (_("\nWatchpoint %pF deleted because the program has "
 220                          "left the block in\n"
 221                          "which its expression is valid.\n"),
 222                          signed_field ("wpnum", b->number));
 223
 224      - '%p[' - output the following text in a specified style.
 225        '%p]' - output the following text in the default style.
 226
 227        The argument to '%p[' is a ui_file_style pointer.  The argument
 228        to '%p]' must be nullptr.
 229
 230        This is useful when you want to output some portion of a string
 231        literal in some style.  E.g.:
 232
 233          uiout->message (_(" %p[<repeats %u times>%p]"),
 234                          metadata_style.style ().ptr (),
 235                          reps, repeats, nullptr);
 236
 237      - '%ps' - output a styled string.
 238
 239        The argument is the result of a call to styled_string.  This is
 240        useful when you want to output some runtime-generated string in
 241        some style.  E.g.:
 242
 243          uiout->message (_("this is a target address %ps.\n"),
 244                          styled_string (address_style.style (),
 245                                         paddress (gdbarch, pc)));
 246
 247      Note that these all "abuse" the %p printf format spec, in order
 248      to be compatible with GCC's printf format checking.  This is OK
 249      because code in GDB that wants to print a host address should use
 250      host_address_to_string instead of %p.  */
 251   void message (const char *format, ...) ATTRIBUTE_PRINTF (2, 3);
 252   void vmessage (const ui_file_style &in_style,
 253                  const char *format, va_list args) ATTRIBUTE_PRINTF (3, 0);
 254
 255   void wrap_hint (const char *identstring);
 256
 257   void flush ();
 258
 259   /* Redirect the output of a ui_out object temporarily.  */
 260   void redirect (ui_file *outstream);
 261
 262   ui_out_flags test_flags (ui_out_flags mask);
 263
 264   /* HACK: Code in GDB is currently checking to see the type of ui_out
 265      builder when determining which output to produce.  This function is
 266      a hack to encapsulate that test.  Once GDB manages to separate the
 267      CLI/MI from the core of GDB the problem should just go away ....  */
 268
 269   bool is_mi_like_p () const;
 270
 271   bool query_table_field (int colno, int *width, int *alignment,
 272                           const char **col_name);
 273
 274   /* Return true if this stream is prepared to handle style
 275      escapes.  */
 276   virtual bool can_emit_style_escape () const = 0;
 277
 278  protected:
 279
 280   virtual void do_table_begin (int nbrofcols, int nr_rows, const char *tblid)
 281     = 0;
 282   virtual void do_table_body () = 0;
 283   virtual void do_table_end () = 0;
 284   virtual void do_table_header (int width, ui_align align,
 285                                 const std::string &col_name,
 286                                 const std::string &col_hdr) = 0;
 287
 288   virtual void do_begin (ui_out_type type, const char *id) = 0;
 289   virtual void do_end (ui_out_type type) = 0;
 290   virtual void do_field_signed (int fldno, int width, ui_align align,
 291                                 const char *fldname, LONGEST value) = 0;
 292   virtual void do_field_unsigned (int fldno, int width, ui_align align,
 293                                   const char *fldname, ULONGEST value) = 0;
 294   virtual void do_field_skip (int fldno, int width, ui_align align,
 295                               const char *fldname) = 0;
 296   virtual void do_field_string (int fldno, int width, ui_align align,
 297                                 const char *fldname, const char *string,
 298                                 const ui_file_style &style) = 0;
 299   virtual void do_field_fmt (int fldno, int width, ui_align align,
 300                              const char *fldname, const ui_file_style &style,
 301                              const char *format, va_list args)
 302     ATTRIBUTE_PRINTF (7, 0) = 0;
 303   virtual void do_spaces (int numspaces) = 0;
 304   virtual void do_text (const char *string) = 0;
 305   virtual void do_message (const ui_file_style &style,
 306                            const char *format, va_list args)
 307     ATTRIBUTE_PRINTF (3,0) = 0;
 308   virtual void do_wrap_hint (const char *identstring) = 0;
 309   virtual void do_flush () = 0;
 310   virtual void do_redirect (struct ui_file *outstream) = 0;
 311
 312   /* Set as not MI-like by default.  It is overridden in subclasses if
 313      necessary.  */
 314
 315   virtual bool do_is_mi_like_p () const
 316   { return false; }
 317
 318  private:
 319   void call_do_message (const ui_file_style &style, const char *format,
 320                         ...);
 321
 322   ui_out_flags m_flags;
 323
 324   /* Vector to store and track the ui-out levels.  */
 325   std::vector<std::unique_ptr<ui_out_level>> m_levels;
 326
 327   /* A table, if any.  At present only a single table is supported.  */
 328   std::unique_ptr<ui_out_table> m_table_up;
 329
 330   void verify_field (int *fldno, int *width, ui_align *align);
 331
 332   int level () const;
 333   ui_out_level *current_level () const;
 334 };
 335
 336 /* Start a new tuple or list on construction, and end it on
 337    destruction.  Normally this is used via the typedefs
 338    ui_out_emit_tuple and ui_out_emit_list.  */
 339 template<ui_out_type Type>
 340 class ui_out_emit_type
 341 {
 342 public:
 343
 344   ui_out_emit_type (struct ui_out *uiout, const char *id)
 345     : m_uiout (uiout)
 346   {
 347     uiout->begin (Type, id);
 348   }
 349
 350   ~ui_out_emit_type ()
 351   {
 352     m_uiout->end (Type);
 353   }
 354
 355   DISABLE_COPY_AND_ASSIGN (ui_out_emit_type<Type>);
 356
 357 private:
 358
 359   struct ui_out *m_uiout;
 360 };
 361
 362 typedef ui_out_emit_type<ui_out_type_tuple> ui_out_emit_tuple;
 363 typedef ui_out_emit_type<ui_out_type_list> ui_out_emit_list;
 364
 365 /* Start a new table on construction, and end the table on
 366    destruction.  */
 367 class ui_out_emit_table
 368 {
 369 public:
 370
 371   ui_out_emit_table (struct ui_out *uiout, int nr_cols, int nr_rows,
 372                      const char *tblid)
 373     : m_uiout (uiout)
 374   {
 375     m_uiout->table_begin (nr_cols, nr_rows, tblid);
 376   }
 377
 378   ~ui_out_emit_table ()
 379   {
 380     m_uiout->table_end ();
 381   }
 382
 383   ui_out_emit_table (const ui_out_emit_table &) = delete;
 384   ui_out_emit_table &operator= (const ui_out_emit_table &) = delete;
 385
 386 private:
 387
 388   struct ui_out *m_uiout;
 389 };
 390
 391 /* On destruction, pop the last redirection by calling the uiout's
 392    redirect method with a NULL parameter.  */
 393 class ui_out_redirect_pop
 394 {
 395 public:
 396
 397   ui_out_redirect_pop (ui_out *uiout)
 398     : m_uiout (uiout)
 399   {
 400   }
 401
 402   ~ui_out_redirect_pop ()
 403   {
 404     m_uiout->redirect (NULL);
 405   }
 406
 407   ui_out_redirect_pop (const ui_out_redirect_pop &) = delete;
 408   ui_out_redirect_pop &operator= (const ui_out_redirect_pop &) = delete;
 409
 410 private:
 411   struct ui_out *m_uiout;
 412 };
 413
 414 #endif /* UI_OUT_H */