gdb/ui-out.c

   1 /* Output generating routines for GDB.
   2
   3    Copyright (C) 1999-2016 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 #include "defs.h"
  24 #include "expression.h"         /* For language.h */
  25 #include "language.h"
  26 #include "ui-out.h"
  27
  28 /* table header structures */
  29
  30 struct ui_out_hdr
  31   {
  32     int colno;
  33     int width;
  34     enum ui_align alignment;
  35     char *col_name;
  36     char *colhdr;
  37     struct ui_out_hdr *next;
  38   };
  39
  40 struct ui_out_level
  41   {
  42     /* Count each field; the first element is for non-list fields.  */
  43     int field_count;
  44     /* The type of this level.  */
  45     enum ui_out_type type;
  46   };
  47
  48 /* Define uiout->level vector types and operations.  */
  49 typedef struct ui_out_level *ui_out_level_p;
  50 DEF_VEC_P (ui_out_level_p);
  51
  52 /* Tables are special.  Maintain a separate structure that tracks
  53    their state.  At present an output can only contain a single table
  54    but that restriction might eventually be lifted.  */
  55
  56 struct ui_out_table
  57 {
  58   /* If on, a table is being generated.  */
  59   int flag;
  60
  61   /* If on, the body of a table is being generated.  If off, the table
  62      header is being generated.  */
  63   int body_flag;
  64
  65   /* The level at which each entry of the table is to be found.  A row
  66      (a tuple) is made up of entries.  Consequently ENTRY_LEVEL is one
  67      above that of the table.  */
  68   int entry_level;
  69
  70   /* Number of table columns (as specified in the table_begin call).  */
  71   int columns;
  72
  73   /* String identifying the table (as specified in the table_begin
  74      call).  */
  75   char *id;
  76
  77   /* Points to the first table header (if any).  */
  78   struct ui_out_hdr *header_first;
  79
  80   /* Points to the last table header (if any).  */
  81   struct ui_out_hdr *header_last;
  82
  83   /* Points to header of NEXT column to format.  */
  84   struct ui_out_hdr *header_next;
  85
  86 };
  87
  88
  89 /* The ui_out structure */
  90 /* Any change here requires a corresponding one in the initialization
  91    of the default uiout, which is statically initialized.  */
  92
  93 struct ui_out
  94   {
  95     int flags;
  96     /* Specific implementation of ui-out.  */
  97     const struct ui_out_impl *impl;
  98     void *data;
  99
 100     /* Current level.  */
 101     int level;
 102
 103     /* Vector to store and track the ui-out levels.  */
 104     VEC (ui_out_level_p) *levels;
 105
 106     /* A table, if any.  At present only a single table is supported.  */
 107     struct ui_out_table table;
 108   };
 109
 110 /* The current (inner most) level.  */
 111 static struct ui_out_level *
 112 current_level (struct ui_out *uiout)
 113 {
 114   return VEC_index (ui_out_level_p, uiout->levels, uiout->level);
 115 }
 116
 117 /* Create a new level, of TYPE.  Return the new level's index.  */
 118 static int
 119 push_level (struct ui_out *uiout,
 120             enum ui_out_type type)
 121 {
 122   struct ui_out_level *current;
 123
 124   uiout->level++;
 125   current = XNEW (struct ui_out_level);
 126   current->field_count = 0;
 127   current->type = type;
 128   VEC_safe_push (ui_out_level_p, uiout->levels, current);
 129   return uiout->level;
 130 }
 131
 132 /* Discard the current level, return the discarded level's index.
 133    TYPE is the type of the level being discarded.  */
 134 static int
 135 pop_level (struct ui_out *uiout,
 136            enum ui_out_type type)
 137 {
 138   struct ui_out_level *current;
 139
 140   /* We had better not underflow the buffer.  */
 141   gdb_assert (uiout->level > 0);
 142   gdb_assert (current_level (uiout)->type == type);
 143   current = VEC_pop (ui_out_level_p, uiout->levels);
 144   xfree (current);
 145   uiout->level--;
 146   return uiout->level + 1;
 147 }
 148
 149 /* These are the interfaces to implementation functions.  */
 150
 151 static void uo_table_begin (struct ui_out *uiout, int nbrofcols,
 152                             int nr_rows, const char *tblid);
 153 static void uo_table_body (struct ui_out *uiout);
 154 static void uo_table_end (struct ui_out *uiout);
 155 static void uo_table_header (struct ui_out *uiout, int width,
 156                              enum ui_align align, const char *col_name,
 157                              const char *colhdr);
 158 static void uo_begin (struct ui_out *uiout,
 159                       enum ui_out_type type,
 160                       int level, const char *id);
 161 static void uo_end (struct ui_out *uiout,
 162                     enum ui_out_type type,
 163                     int level);
 164 static void uo_field_int (struct ui_out *uiout, int fldno, int width,
 165                           enum ui_align align, const char *fldname, int value);
 166 static void uo_field_skip (struct ui_out *uiout, int fldno, int width,
 167                            enum ui_align align, const char *fldname);
 168 static void uo_field_fmt (struct ui_out *uiout, int fldno, int width,
 169                           enum ui_align align, const char *fldname,
 170                           const char *format, va_list args)
 171      ATTRIBUTE_PRINTF (6, 0);
 172 static void uo_spaces (struct ui_out *uiout, int numspaces);
 173 static void uo_text (struct ui_out *uiout, const char *string);
 174 static void uo_message (struct ui_out *uiout, int verbosity,
 175                         const char *format, va_list args)
 176      ATTRIBUTE_PRINTF (3, 0);
 177 static void uo_wrap_hint (struct ui_out *uiout, char *identstring);
 178 static void uo_flush (struct ui_out *uiout);
 179 static int uo_redirect (struct ui_out *uiout, struct ui_file *outstream);
 180 static void uo_data_destroy (struct ui_out *uiout);
 181
 182 /* Prototypes for local functions */
 183
 184 extern void _initialize_ui_out (void);
 185 static void append_header_to_list (struct ui_out *uiout, int width,
 186                                    enum ui_align alignment, const char *col_name,
 187                                    const char *colhdr);
 188 static int get_next_header (struct ui_out *uiout, int *colno, int *width,
 189                             enum ui_align *alignment, char **colhdr);
 190 static void clear_header_list (struct ui_out *uiout);
 191 static void clear_table (struct ui_out *uiout);
 192 static void verify_field (struct ui_out *uiout, int *fldno, int *width,
 193                           enum ui_align *align);
 194
 195 /* exported functions (ui_out API) */
 196
 197 /* Mark beginning of a table.  */
 198
 199 static void
 200 ui_out_table_begin (struct ui_out *uiout, int nbrofcols,
 201                     int nr_rows,
 202                     const char *tblid)
 203 {
 204   if (uiout->table.flag)
 205     internal_error (__FILE__, __LINE__,
 206                     _("tables cannot be nested; table_begin found before \
 207 previous table_end."));
 208
 209   uiout->table.flag = 1;
 210   uiout->table.body_flag = 0;
 211   uiout->table.entry_level = uiout->level + 1;
 212   uiout->table.columns = nbrofcols;
 213   if (tblid != NULL)
 214     uiout->table.id = xstrdup (tblid);
 215   else
 216     uiout->table.id = NULL;
 217   clear_header_list (uiout);
 218
 219   uo_table_begin (uiout, nbrofcols, nr_rows, uiout->table.id);
 220 }
 221
 222 void
 223 ui_out_table_body (struct ui_out *uiout)
 224 {
 225   if (!uiout->table.flag)
 226     internal_error (__FILE__, __LINE__,
 227                     _("table_body outside a table is not valid; it must be \
 228 after a table_begin and before a table_end."));
 229   if (uiout->table.body_flag)
 230     internal_error (__FILE__, __LINE__,
 231                     _("extra table_body call not allowed; there must be \
 232 only one table_body after a table_begin and before a table_end."));
 233   if (uiout->table.header_next->colno != uiout->table.columns)
 234     internal_error (__FILE__, __LINE__,
 235                     _("number of headers differ from number of table \
 236 columns."));
 237
 238   uiout->table.body_flag = 1;
 239   uiout->table.header_next = uiout->table.header_first;
 240
 241   uo_table_body (uiout);
 242 }
 243
 244 static void
 245 ui_out_table_end (struct ui_out *uiout)
 246 {
 247   if (!uiout->table.flag)
 248     internal_error (__FILE__, __LINE__,
 249                     _("misplaced table_end or missing table_begin."));
 250
 251   uiout->table.entry_level = 0;
 252   uiout->table.body_flag = 0;
 253   uiout->table.flag = 0;
 254
 255   uo_table_end (uiout);
 256   clear_table (uiout);
 257 }
 258
 259 void
 260 ui_out_table_header (struct ui_out *uiout, int width, enum ui_align alignment,
 261                      const char *col_name,
 262                      const char *colhdr)
 263 {
 264   if (!uiout->table.flag || uiout->table.body_flag)
 265     internal_error (__FILE__, __LINE__,
 266                     _("table header must be specified after table_begin \
 267 and before table_body."));
 268
 269   append_header_to_list (uiout, width, alignment, col_name, colhdr);
 270
 271   uo_table_header (uiout, width, alignment, col_name, colhdr);
 272 }
 273
 274 static void
 275 do_cleanup_table_end (void *data)
 276 {
 277   struct ui_out *ui_out = (struct ui_out *) data;
 278
 279   ui_out_table_end (ui_out);
 280 }
 281
 282 struct cleanup *
 283 make_cleanup_ui_out_table_begin_end (struct ui_out *ui_out, int nr_cols,
 284                                      int nr_rows, const char *tblid)
 285 {
 286   ui_out_table_begin (ui_out, nr_cols, nr_rows, tblid);
 287   return make_cleanup (do_cleanup_table_end, ui_out);
 288 }
 289
 290 void
 291 ui_out_begin (struct ui_out *uiout,
 292               enum ui_out_type type,
 293               const char *id)
 294 {
 295   int new_level;
 296
 297   if (uiout->table.flag && !uiout->table.body_flag)
 298     internal_error (__FILE__, __LINE__,
 299                     _("table header or table_body expected; lists must be \
 300 specified after table_body."));
 301
 302   /* Be careful to verify the ``field'' before the new tuple/list is
 303      pushed onto the stack.  That way the containing list/table/row is
 304      verified and not the newly created tuple/list.  This verification
 305      is needed (at least) for the case where a table row entry
 306      contains either a tuple/list.  For that case bookkeeping such as
 307      updating the column count or advancing to the next heading still
 308      needs to be performed.  */
 309   {
 310     int fldno;
 311     int width;
 312     enum ui_align align;
 313
 314     verify_field (uiout, &fldno, &width, &align);
 315   }
 316
 317   new_level = push_level (uiout, type);
 318
 319   /* If the push puts us at the same level as a table row entry, we've
 320      got a new table row.  Put the header pointer back to the start.  */
 321   if (uiout->table.body_flag
 322       && uiout->table.entry_level == new_level)
 323     uiout->table.header_next = uiout->table.header_first;
 324
 325   uo_begin (uiout, type, new_level, id);
 326 }
 327
 328 void
 329 ui_out_end (struct ui_out *uiout,
 330             enum ui_out_type type)
 331 {
 332   int old_level = pop_level (uiout, type);
 333
 334   uo_end (uiout, type, old_level);
 335 }
 336
 337 struct ui_out_end_cleanup_data
 338 {
 339   struct ui_out *uiout;
 340   enum ui_out_type type;
 341 };
 342
 343 static void
 344 do_cleanup_end (void *data)
 345 {
 346   struct ui_out_end_cleanup_data *end_cleanup_data
 347     = (struct ui_out_end_cleanup_data *) data;
 348
 349   ui_out_end (end_cleanup_data->uiout, end_cleanup_data->type);
 350   xfree (end_cleanup_data);
 351 }
 352
 353 static struct cleanup *
 354 make_cleanup_ui_out_end (struct ui_out *uiout,
 355                          enum ui_out_type type)
 356 {
 357   struct ui_out_end_cleanup_data *end_cleanup_data;
 358
 359   end_cleanup_data = XNEW (struct ui_out_end_cleanup_data);
 360   end_cleanup_data->uiout = uiout;
 361   end_cleanup_data->type = type;
 362   return make_cleanup (do_cleanup_end, end_cleanup_data);
 363 }
 364
 365 struct cleanup *
 366 make_cleanup_ui_out_tuple_begin_end (struct ui_out *uiout,
 367                                      const char *id)
 368 {
 369   ui_out_begin (uiout, ui_out_type_tuple, id);
 370   return make_cleanup_ui_out_end (uiout, ui_out_type_tuple);
 371 }
 372
 373 struct cleanup *
 374 make_cleanup_ui_out_list_begin_end (struct ui_out *uiout,
 375                                     const char *id)
 376 {
 377   ui_out_begin (uiout, ui_out_type_list, id);
 378   return make_cleanup_ui_out_end (uiout, ui_out_type_list);
 379 }
 380
 381 void
 382 ui_out_field_int (struct ui_out *uiout,
 383                   const char *fldname,
 384                   int value)
 385 {
 386   int fldno;
 387   int width;
 388   enum ui_align align;
 389
 390   verify_field (uiout, &fldno, &width, &align);
 391
 392   uo_field_int (uiout, fldno, width, align, fldname, value);
 393 }
 394
 395 void
 396 ui_out_field_fmt_int (struct ui_out *uiout,
 397                       int input_width,
 398                       enum ui_align input_align,
 399                       const char *fldname,
 400                       int value)
 401 {
 402   int fldno;
 403   int width;
 404   enum ui_align align;
 405
 406   verify_field (uiout, &fldno, &width, &align);
 407
 408   uo_field_int (uiout, fldno, input_width, input_align, fldname, value);
 409 }
 410
 411 /* Documented in ui-out.h.  */
 412
 413 void
 414 ui_out_field_core_addr (struct ui_out *uiout,
 415                         const char *fldname,
 416                         struct gdbarch *gdbarch,
 417                         CORE_ADDR address)
 418 {
 419   ui_out_field_string (uiout, fldname,
 420                        print_core_address (gdbarch, address));
 421 }
 422
 423 void
 424 ui_out_field_stream (struct ui_out *uiout,
 425                      const char *fldname,
 426                      struct ui_file *stream)
 427 {
 428   std::string buffer = ui_file_as_string (stream);
 429
 430   if (!buffer.empty ())
 431     ui_out_field_string (uiout, fldname, buffer.c_str ());
 432   else
 433     ui_out_field_skip (uiout, fldname);
 434   ui_file_rewind (stream);
 435 }
 436
 437 /* Used to omit a field.  */
 438
 439 void
 440 ui_out_field_skip (struct ui_out *uiout,
 441                    const char *fldname)
 442 {
 443   int fldno;
 444   int width;
 445   enum ui_align align;
 446
 447   verify_field (uiout, &fldno, &width, &align);
 448
 449   uo_field_skip (uiout, fldno, width, align, fldname);
 450 }
 451
 452 void
 453 ui_out_field_string (struct ui_out *uiout,
 454                      const char *fldname,
 455                      const char *string)
 456 {
 457   int fldno;
 458   int width;
 459   enum ui_align align;
 460
 461   verify_field (uiout, &fldno, &width, &align);
 462
 463   uo_field_string (uiout, fldno, width, align, fldname, string);
 464 }
 465
 466 /* VARARGS */
 467 void
 468 ui_out_field_fmt (struct ui_out *uiout,
 469                   const char *fldname,
 470                   const char *format, ...)
 471 {
 472   va_list args;
 473   int fldno;
 474   int width;
 475   enum ui_align align;
 476
 477   /* Will not align, but has to call anyway.  */
 478   verify_field (uiout, &fldno, &width, &align);
 479
 480   va_start (args, format);
 481
 482   uo_field_fmt (uiout, fldno, width, align, fldname, format, args);
 483
 484   va_end (args);
 485 }
 486
 487 void
 488 ui_out_spaces (struct ui_out *uiout, int numspaces)
 489 {
 490   uo_spaces (uiout, numspaces);
 491 }
 492
 493 void
 494 ui_out_text (struct ui_out *uiout,
 495              const char *string)
 496 {
 497   uo_text (uiout, string);
 498 }
 499
 500 void
 501 ui_out_message (struct ui_out *uiout, int verbosity,
 502                 const char *format,...)
 503 {
 504   va_list args;
 505
 506   va_start (args, format);
 507   uo_message (uiout, verbosity, format, args);
 508   va_end (args);
 509 }
 510
 511 void
 512 ui_out_wrap_hint (struct ui_out *uiout, char *identstring)
 513 {
 514   uo_wrap_hint (uiout, identstring);
 515 }
 516
 517 void
 518 ui_out_flush (struct ui_out *uiout)
 519 {
 520   uo_flush (uiout);
 521 }
 522
 523 int
 524 ui_out_redirect (struct ui_out *uiout, struct ui_file *outstream)
 525 {
 526   return uo_redirect (uiout, outstream);
 527 }
 528
 529 /* Set the flags specified by the mask given.  */
 530 int
 531 ui_out_set_flags (struct ui_out *uiout, int mask)
 532 {
 533   int oldflags = uiout->flags;
 534
 535   uiout->flags |= mask;
 536   return oldflags;
 537 }
 538
 539 /* Clear the flags specified by the mask given.  */
 540 int
 541 ui_out_clear_flags (struct ui_out *uiout, int mask)
 542 {
 543   int oldflags = uiout->flags;
 544
 545   uiout->flags &= ~mask;
 546   return oldflags;
 547 }
 548
 549 /* Test the flags against the mask given.  */
 550 int
 551 ui_out_test_flags (struct ui_out *uiout, int mask)
 552 {
 553   return (uiout->flags & mask);
 554 }
 555
 556 /* Obtain the current verbosity level (as stablished by the
 557    'set verbositylevel' command.  */
 558
 559 int
 560 ui_out_get_verblvl (struct ui_out *uiout)
 561 {
 562   /* FIXME: not implemented yet.  */
 563   return 0;
 564 }
 565
 566 int
 567 ui_out_is_mi_like_p (struct ui_out *uiout)
 568 {
 569   return uiout->impl->is_mi_like_p;
 570 }
 571
 572 /* Interface to the implementation functions.  */
 573
 574 void
 575 uo_table_begin (struct ui_out *uiout, int nbrofcols,
 576                 int nr_rows,
 577                 const char *tblid)
 578 {
 579   if (!uiout->impl->table_begin)
 580     return;
 581   uiout->impl->table_begin (uiout, nbrofcols, nr_rows, tblid);
 582 }
 583
 584 void
 585 uo_table_body (struct ui_out *uiout)
 586 {
 587   if (!uiout->impl->table_body)
 588     return;
 589   uiout->impl->table_body (uiout);
 590 }
 591
 592 void
 593 uo_table_end (struct ui_out *uiout)
 594 {
 595   if (!uiout->impl->table_end)
 596     return;
 597   uiout->impl->table_end (uiout);
 598 }
 599
 600 void
 601 uo_table_header (struct ui_out *uiout, int width, enum ui_align align,
 602                  const char *col_name,
 603                  const char *colhdr)
 604 {
 605   if (!uiout->impl->table_header)
 606     return;
 607   uiout->impl->table_header (uiout, width, align, col_name, colhdr);
 608 }
 609
 610 /* Clear the table associated with UIOUT.  */
 611
 612 static void
 613 clear_table (struct ui_out *uiout)
 614 {
 615   xfree (uiout->table.id);
 616   uiout->table.id = NULL;
 617   clear_header_list (uiout);
 618 }
 619
 620 void
 621 uo_begin (struct ui_out *uiout,
 622           enum ui_out_type type,
 623           int level,
 624           const char *id)
 625 {
 626   if (uiout->impl->begin == NULL)
 627     return;
 628   uiout->impl->begin (uiout, type, level, id);
 629 }
 630
 631 void
 632 uo_end (struct ui_out *uiout,
 633         enum ui_out_type type,
 634         int level)
 635 {
 636   if (uiout->impl->end == NULL)
 637     return;
 638   uiout->impl->end (uiout, type, level);
 639 }
 640
 641 void
 642 uo_field_int (struct ui_out *uiout, int fldno, int width, enum ui_align align,
 643               const char *fldname,
 644               int value)
 645 {
 646   if (!uiout->impl->field_int)
 647     return;
 648   uiout->impl->field_int (uiout, fldno, width, align, fldname, value);
 649 }
 650
 651 void
 652 uo_field_skip (struct ui_out *uiout, int fldno, int width, enum ui_align align,
 653                const char *fldname)
 654 {
 655   if (!uiout->impl->field_skip)
 656     return;
 657   uiout->impl->field_skip (uiout, fldno, width, align, fldname);
 658 }
 659
 660 void
 661 uo_field_string (struct ui_out *uiout, int fldno, int width,
 662                  enum ui_align align,
 663                  const char *fldname,
 664                  const char *string)
 665 {
 666   if (!uiout->impl->field_string)
 667     return;
 668   uiout->impl->field_string (uiout, fldno, width, align, fldname, string);
 669 }
 670
 671 void
 672 uo_field_fmt (struct ui_out *uiout, int fldno, int width, enum ui_align align,
 673               const char *fldname,
 674               const char *format,
 675               va_list args)
 676 {
 677   if (!uiout->impl->field_fmt)
 678     return;
 679   uiout->impl->field_fmt (uiout, fldno, width, align, fldname, format, args);
 680 }
 681
 682 void
 683 uo_spaces (struct ui_out *uiout, int numspaces)
 684 {
 685   if (!uiout->impl->spaces)
 686     return;
 687   uiout->impl->spaces (uiout, numspaces);
 688 }
 689
 690 void
 691 uo_text (struct ui_out *uiout,
 692          const char *string)
 693 {
 694   if (!uiout->impl->text)
 695     return;
 696   uiout->impl->text (uiout, string);
 697 }
 698
 699 void
 700 uo_message (struct ui_out *uiout, int verbosity,
 701             const char *format,
 702             va_list args)
 703 {
 704   if (!uiout->impl->message)
 705     return;
 706   uiout->impl->message (uiout, verbosity, format, args);
 707 }
 708
 709 void
 710 uo_wrap_hint (struct ui_out *uiout, char *identstring)
 711 {
 712   if (!uiout->impl->wrap_hint)
 713     return;
 714   uiout->impl->wrap_hint (uiout, identstring);
 715 }
 716
 717 void
 718 uo_flush (struct ui_out *uiout)
 719 {
 720   if (!uiout->impl->flush)
 721     return;
 722   uiout->impl->flush (uiout);
 723 }
 724
 725 int
 726 uo_redirect (struct ui_out *uiout, struct ui_file *outstream)
 727 {
 728   if (!uiout->impl->redirect)
 729     return -1;
 730   uiout->impl->redirect (uiout, outstream);
 731   return 0;
 732 }
 733
 734 void
 735 uo_data_destroy (struct ui_out *uiout)
 736 {
 737   if (!uiout->impl->data_destroy)
 738     return;
 739
 740   uiout->impl->data_destroy (uiout);
 741 }
 742
 743 /* local functions */
 744
 745 /* List of column headers manipulation routines.  */
 746
 747 static void
 748 clear_header_list (struct ui_out *uiout)
 749 {
 750   while (uiout->table.header_first != NULL)
 751     {
 752       uiout->table.header_next = uiout->table.header_first;
 753       uiout->table.header_first = uiout->table.header_first->next;
 754       xfree (uiout->table.header_next->colhdr);
 755       xfree (uiout->table.header_next->col_name);
 756       xfree (uiout->table.header_next);
 757     }
 758   gdb_assert (uiout->table.header_first == NULL);
 759   uiout->table.header_last = NULL;
 760   uiout->table.header_next = NULL;
 761 }
 762
 763 static void
 764 append_header_to_list (struct ui_out *uiout,
 765                        int width,
 766                        enum ui_align alignment,
 767                        const char *col_name,
 768                        const char *colhdr)
 769 {
 770   struct ui_out_hdr *temphdr;
 771
 772   temphdr = XNEW (struct ui_out_hdr);
 773   temphdr->width = width;
 774   temphdr->alignment = alignment;
 775   /* We have to copy the column title as the original may be an
 776      automatic.  */
 777   if (colhdr != NULL)
 778     temphdr->colhdr = xstrdup (colhdr);
 779   else
 780     temphdr->colhdr = NULL;
 781
 782   if (col_name != NULL)
 783     temphdr->col_name = xstrdup (col_name);
 784   else if (colhdr != NULL)
 785     temphdr->col_name = xstrdup (colhdr);
 786   else
 787     temphdr->col_name = NULL;
 788
 789   temphdr->next = NULL;
 790   if (uiout->table.header_first == NULL)
 791     {
 792       temphdr->colno = 1;
 793       uiout->table.header_first = temphdr;
 794       uiout->table.header_last = temphdr;
 795     }
 796   else
 797     {
 798       temphdr->colno = uiout->table.header_last->colno + 1;
 799       uiout->table.header_last->next = temphdr;
 800       uiout->table.header_last = temphdr;
 801     }
 802   uiout->table.header_next = uiout->table.header_last;
 803 }
 804
 805 /* Extract the format information for the NEXT header and advance
 806    the header pointer.  Return 0 if there was no next header.  */
 807
 808 static int
 809 get_next_header (struct ui_out *uiout,
 810                  int *colno,
 811                  int *width,
 812                  enum ui_align *alignment,
 813                  char **colhdr)
 814 {
 815   /* There may be no headers at all or we may have used all columns.  */
 816   if (uiout->table.header_next == NULL)
 817     return 0;
 818   *colno = uiout->table.header_next->colno;
 819   *width = uiout->table.header_next->width;
 820   *alignment = uiout->table.header_next->alignment;
 821   *colhdr = uiout->table.header_next->colhdr;
 822   /* Advance the header pointer to the next entry.  */
 823   uiout->table.header_next = uiout->table.header_next->next;
 824   return 1;
 825 }
 826
 827
 828 /* Verify that the field/tuple/list is correctly positioned.  Return
 829    the field number and corresponding alignment (if
 830    available/applicable).  */
 831
 832 static void
 833 verify_field (struct ui_out *uiout, int *fldno, int *width,
 834               enum ui_align *align)
 835 {
 836   struct ui_out_level *current = current_level (uiout);
 837   char *text;
 838
 839   if (uiout->table.flag)
 840     {
 841       if (!uiout->table.body_flag)
 842         internal_error (__FILE__, __LINE__,
 843                         _("table_body missing; table fields must be \
 844 specified after table_body and inside a list."));
 845       /* NOTE: cagney/2001-12-08: There was a check here to ensure
 846          that this code was only executed when uiout->level was
 847          greater than zero.  That no longer applies - this code is run
 848          before each table row tuple is started and at that point the
 849          level is zero.  */
 850     }
 851
 852   current->field_count += 1;
 853
 854   if (uiout->table.body_flag
 855       && uiout->table.entry_level == uiout->level
 856       && get_next_header (uiout, fldno, width, align, &text))
 857     {
 858       if (*fldno != current->field_count)
 859         internal_error (__FILE__, __LINE__,
 860                         _("ui-out internal error in handling headers."));
 861     }
 862   else
 863     {
 864       *width = 0;
 865       *align = ui_noalign;
 866       *fldno = current->field_count;
 867     }
 868 }
 869
 870
 871 /* Access to ui-out members data.  */
 872
 873 void *
 874 ui_out_data (struct ui_out *uiout)
 875 {
 876   return uiout->data;
 877 }
 878
 879 /* Access table field parameters.  */
 880 int
 881 ui_out_query_field (struct ui_out *uiout, int colno,
 882                     int *width, int *alignment, char **col_name)
 883 {
 884   struct ui_out_hdr *hdr;
 885
 886   if (!uiout->table.flag)
 887     return 0;
 888
 889   for (hdr = uiout->table.header_first; hdr; hdr = hdr->next)
 890     if (hdr->colno == colno)
 891       {
 892         *width = hdr->width;
 893         *alignment = hdr->alignment;
 894         *col_name = hdr->col_name;
 895         return 1;
 896       }
 897
 898   return 0;
 899 }
 900
 901 /* Initialize private members at startup.  */
 902
 903 struct ui_out *
 904 ui_out_new (const struct ui_out_impl *impl, void *data,
 905             int flags)
 906 {
 907   struct ui_out *uiout = XNEW (struct ui_out);
 908   struct ui_out_level *current = XNEW (struct ui_out_level);
 909
 910   uiout->data = data;
 911   uiout->impl = impl;
 912   uiout->flags = flags;
 913   uiout->table.flag = 0;
 914   uiout->table.body_flag = 0;
 915   uiout->level = 0;
 916   uiout->levels = NULL;
 917
 918   /* Create uiout->level 0, the default level.  */
 919   current->type = ui_out_type_tuple;
 920   current->field_count = 0;
 921   VEC_safe_push (ui_out_level_p, uiout->levels, current);
 922
 923   uiout->table.id = NULL;
 924   uiout->table.header_first = NULL;
 925   uiout->table.header_last = NULL;
 926   uiout->table.header_next = NULL;
 927   return uiout;
 928 }
 929
 930 /* Free  UIOUT and the memory areas it references.  */
 931
 932 void
 933 ui_out_destroy (struct ui_out *uiout)
 934 {
 935   int i;
 936   struct ui_out_level *current;
 937
 938   /* Make sure that all levels are freed in the case where levels have
 939      been pushed, but not popped before the ui_out object is
 940      destroyed.  */
 941   for (i = 0;
 942        VEC_iterate (ui_out_level_p, uiout->levels, i, current);
 943        ++i)
 944     xfree (current);
 945
 946   VEC_free (ui_out_level_p, uiout->levels);
 947   uo_data_destroy (uiout);
 948   clear_table (uiout);
 949   xfree (uiout);
 950 }
 951
 952 /* Standard gdb initialization hook.  */
 953
 954 void
 955 _initialize_ui_out (void)
 956 {
 957   /* nothing needs to be done */
 958 }