gcc/pretty-print.h

   1 /* Various declarations for language-independent pretty-print subroutines.
   2    Copyright (C) 2002-2017 Free Software Foundation, Inc.
   3    Contributed by Gabriel Dos Reis <gdr@integrable-solutions.net>
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 3, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #ifndef GCC_PRETTY_PRINT_H
  22 #define GCC_PRETTY_PRINT_H
  23
  24 #include "obstack.h"
  25
  26 /* Maximum number of format string arguments.  */
  27 #define PP_NL_ARGMAX   30
  28
  29 /* The type of a text to be formatted according a format specification
  30    along with a list of things.  */
  31 struct text_info
  32 {
  33   const char *format_spec;
  34   va_list *args_ptr;
  35   int err_no;  /* for %m */
  36   void **x_data;
  37   rich_location *m_richloc;
  38
  39   void set_location (unsigned int idx, location_t loc, bool caret_p);
  40   location_t get_location (unsigned int index_of_location) const;
  41 };
  42
  43 /* How often diagnostics are prefixed by their locations:
  44    o DIAGNOSTICS_SHOW_PREFIX_NEVER: never - not yet supported;
  45    o DIAGNOSTICS_SHOW_PREFIX_ONCE: emit only once;
  46    o DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE: emit each time a physical
  47    line is started.  */
  48 enum diagnostic_prefixing_rule_t
  49 {
  50   DIAGNOSTICS_SHOW_PREFIX_ONCE       = 0x0,
  51   DIAGNOSTICS_SHOW_PREFIX_NEVER      = 0x1,
  52   DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE = 0x2
  53 };
  54
  55 /* The chunk_info data structure forms a stack of the results from the
  56    first phase of formatting (pp_format) which have not yet been
  57    output (pp_output_formatted_text).  A stack is necessary because
  58    the diagnostic starter may decide to generate its own output by way
  59    of the formatter.  */
  60 struct chunk_info
  61 {
  62   /* Pointer to previous chunk on the stack.  */
  63   struct chunk_info *prev;
  64
  65   /* Array of chunks to output.  Each chunk is a NUL-terminated string.
  66      In the first phase of formatting, even-numbered chunks are
  67      to be output verbatim, odd-numbered chunks are format specifiers.
  68      The second phase replaces all odd-numbered chunks with formatted
  69      text, and the third phase simply emits all the chunks in sequence
  70      with appropriate line-wrapping.  */
  71   const char *args[PP_NL_ARGMAX * 2];
  72 };
  73
  74 /* The output buffer datatype.  This is best seen as an abstract datatype
  75    whose fields should not be accessed directly by clients.  */
  76 struct output_buffer
  77 {
  78   output_buffer ();
  79   ~output_buffer ();
  80
  81   /* Obstack where the text is built up.  */
  82   struct obstack formatted_obstack;
  83
  84   /* Obstack containing a chunked representation of the format
  85      specification plus arguments.  */
  86   struct obstack chunk_obstack;
  87
  88   /* Currently active obstack: one of the above two.  This is used so
  89      that the text formatters don't need to know which phase we're in.  */
  90   struct obstack *obstack;
  91
  92   /* Stack of chunk arrays.  These come from the chunk_obstack.  */
  93   struct chunk_info *cur_chunk_array;
  94
  95   /* Where to output formatted text.  */
  96   FILE *stream;
  97
  98   /* The amount of characters output so far.  */
  99   int line_length;
 100
 101   /* This must be large enough to hold any printed integer or
 102      floating-point value.  */
 103   char digit_buffer[128];
 104
 105   /* Nonzero means that text should be flushed when
 106      appropriate. Otherwise, text is buffered until either
 107      pp_really_flush or pp_clear_output_area are called.  */
 108   bool flush_p;
 109 };
 110
 111 /* Finishes constructing a NULL-terminated character string representing
 112    the buffered text.  */
 113 static inline const char *
 114 output_buffer_formatted_text (output_buffer *buff)
 115 {
 116   obstack_1grow (buff->obstack, '\0');
 117   return (const char *) obstack_base (buff->obstack);
 118 }
 119
 120 /* Append to the output buffer a string specified by its
 121    STARTing character and LENGTH.  */
 122 static inline void
 123 output_buffer_append_r (output_buffer *buff, const char *start, int length)
 124 {
 125   gcc_checking_assert (start);
 126   obstack_grow (buff->obstack, start, length);
 127   for (int i = 0; i < length; i++)
 128     if (start[i] == '\n')
 129       buff->line_length = 0;
 130     else
 131       buff->line_length++;
 132 }
 133
 134 /*  Return a pointer to the last character emitted in the
 135     output_buffer.  A NULL pointer means no character available.  */
 136 static inline const char *
 137 output_buffer_last_position_in_text (const output_buffer *buff)
 138 {
 139   const char *p = NULL;
 140   struct obstack *text = buff->obstack;
 141
 142   if (obstack_base (text) != obstack_next_free (text))
 143     p = ((const char *) obstack_next_free (text)) - 1;
 144   return p;
 145 }
 146
 147
 148 /* The type of pretty-printer flags passed to clients.  */
 149 typedef unsigned int pp_flags;
 150
 151 enum pp_padding
 152 {
 153   pp_none, pp_before, pp_after
 154 };
 155
 156 /* Structure for switching in and out of verbatim mode in a convenient
 157    manner.  */
 158 struct pp_wrapping_mode_t
 159 {
 160   /* Current prefixing rule.  */
 161   diagnostic_prefixing_rule_t rule;
 162
 163   /* The ideal upper bound of number of characters per line, as suggested
 164      by front-end.  */
 165   int line_cutoff;
 166 };
 167
 168 /* Maximum characters per line in automatic line wrapping mode.
 169    Zero means don't wrap lines.  */
 170 #define pp_line_cutoff(PP)  (PP)->wrapping.line_cutoff
 171
 172 /* Prefixing rule used in formatting a diagnostic message.  */
 173 #define pp_prefixing_rule(PP)  (PP)->wrapping.rule
 174
 175 /* Get or set the wrapping mode as a single entity.  */
 176 #define pp_wrapping_mode(PP) (PP)->wrapping
 177
 178 /* The type of a hook that formats client-specific data onto a pretty_printer.
 179    A client-supplied formatter returns true if everything goes well,
 180    otherwise it returns false.  */
 181 typedef bool (*printer_fn) (pretty_printer *, text_info *, const char *,
 182                             int, bool, bool, bool, bool, const char **);
 183
 184 /* Client supplied function used to decode formats.  */
 185 #define pp_format_decoder(PP) (PP)->format_decoder
 186
 187 /* Base class for an optional client-supplied object for doing additional
 188    processing between stages 2 and 3 of formatted printing.  */
 189 class format_postprocessor
 190 {
 191  public:
 192   virtual ~format_postprocessor () {}
 193   virtual void handle (pretty_printer *) = 0;
 194 };
 195
 196 /* TRUE if a newline character needs to be added before further
 197    formatting.  */
 198 #define pp_needs_newline(PP)  (PP)->need_newline
 199
 200 /* True if PRETTY-PRINTER is in line-wrapping mode.  */
 201 #define pp_is_wrapping_line(PP) (pp_line_cutoff (PP) > 0)
 202
 203 /* The amount of whitespace to be emitted when starting a new line.  */
 204 #define pp_indentation(PP) (PP)->indent_skip
 205
 206 /* True if identifiers are translated to the locale character set on
 207    output.  */
 208 #define pp_translate_identifiers(PP) (PP)->translate_identifiers
 209
 210 /* True if colors should be shown.  */
 211 #define pp_show_color(PP) (PP)->show_color
 212
 213 /* The data structure that contains the bare minimum required to do
 214    proper pretty-printing.  Clients may derived from this structure
 215    and add additional fields they need.  */
 216 struct pretty_printer
 217 {
 218   // Default construct a pretty printer with specified prefix
 219   // and a maximum line length cut off limit.
 220   explicit pretty_printer (const char* = NULL, int = 0);
 221
 222   virtual ~pretty_printer ();
 223
 224   /* Where we print external representation of ENTITY.  */
 225   output_buffer *buffer;
 226
 227   /* The prefix for each new line.  */
 228   const char *prefix;
 229
 230   /* Where to put whitespace around the entity being formatted.  */
 231   pp_padding padding;
 232
 233   /* The real upper bound of number of characters per line, taking into
 234      account the case of a very very looong prefix.  */
 235   int maximum_length;
 236
 237   /* Indentation count.  */
 238   int indent_skip;
 239
 240   /* Current wrapping mode.  */
 241   pp_wrapping_mode_t wrapping;
 242
 243   /* If non-NULL, this function formats a TEXT into the BUFFER.  When called,
 244      TEXT->format_spec points to a format code.  FORMAT_DECODER should call
 245      pp_string (and related functions) to add data to the BUFFER.
 246      FORMAT_DECODER can read arguments from *TEXT->args_pts using VA_ARG.
 247      If the BUFFER needs additional characters from the format string, it
 248      should advance the TEXT->format_spec as it goes.  When FORMAT_DECODER
 249      returns, TEXT->format_spec should point to the last character processed.
 250      The QUOTE and BUFFER_PTR are passed in, to allow for deferring-handling
 251      of format codes (e.g. %H and %I in the C++ frontend).  */
 252   printer_fn format_decoder;
 253
 254   /* If non-NULL, this is called by pp_format once after all format codes
 255      have been processed, to allow for client-specific postprocessing.
 256      This is used by the C++ frontend for handling the %H and %I
 257      format codes (which interract with each other).  */
 258   format_postprocessor *m_format_postprocessor;
 259
 260   /* Nonzero if current PREFIX was emitted at least once.  */
 261   bool emitted_prefix;
 262
 263   /* Nonzero means one should emit a newline before outputting anything.  */
 264   bool need_newline;
 265
 266   /* Nonzero means identifiers are translated to the locale character
 267      set on output.  */
 268   bool translate_identifiers;
 269
 270   /* Nonzero means that text should be colorized.  */
 271   bool show_color;
 272 };
 273
 274 static inline const char *
 275 pp_get_prefix (const pretty_printer *pp) { return pp->prefix; }
 276
 277 #define pp_space(PP)            pp_character (PP, ' ')
 278 #define pp_left_paren(PP)       pp_character (PP, '(')
 279 #define pp_right_paren(PP)      pp_character (PP, ')')
 280 #define pp_left_bracket(PP)     pp_character (PP, '[')
 281 #define pp_right_bracket(PP)    pp_character (PP, ']')
 282 #define pp_left_brace(PP)       pp_character (PP, '{')
 283 #define pp_right_brace(PP)      pp_character (PP, '}')
 284 #define pp_semicolon(PP)        pp_character (PP, ';')
 285 #define pp_comma(PP)            pp_character (PP, ',')
 286 #define pp_dot(PP)              pp_character (PP, '.')
 287 #define pp_colon(PP)            pp_character (PP, ':')
 288 #define pp_colon_colon(PP)      pp_string (PP, "::")
 289 #define pp_arrow(PP)            pp_string (PP, "->")
 290 #define pp_equal(PP)            pp_character (PP, '=')
 291 #define pp_question(PP)         pp_character (PP, '?')
 292 #define pp_bar(PP)              pp_character (PP, '|')
 293 #define pp_bar_bar(PP)          pp_string (PP, "||")
 294 #define pp_carret(PP)           pp_character (PP, '^')
 295 #define pp_ampersand(PP)        pp_character (PP, '&')
 296 #define pp_ampersand_ampersand(PP) pp_string (PP, "&&")
 297 #define pp_less(PP)             pp_character (PP, '<')
 298 #define pp_less_equal(PP)       pp_string (PP, "<=")
 299 #define pp_greater(PP)          pp_character (PP, '>')
 300 #define pp_greater_equal(PP)    pp_string (PP, ">=")
 301 #define pp_plus(PP)             pp_character (PP, '+')
 302 #define pp_minus(PP)            pp_character (PP, '-')
 303 #define pp_star(PP)             pp_character (PP, '*')
 304 #define pp_slash(PP)            pp_character (PP, '/')
 305 #define pp_modulo(PP)           pp_character (PP, '%')
 306 #define pp_exclamation(PP)      pp_character (PP, '!')
 307 #define pp_complement(PP)       pp_character (PP, '~')
 308 #define pp_quote(PP)            pp_character (PP, '\'')
 309 #define pp_backquote(PP)        pp_character (PP, '`')
 310 #define pp_doublequote(PP)      pp_character (PP, '"')
 311 #define pp_underscore(PP)       pp_character (PP, '_')
 312 #define pp_maybe_newline_and_indent(PP, N) \
 313   if (pp_needs_newline (PP)) pp_newline_and_indent (PP, N)
 314 #define pp_scalar(PP, FORMAT, SCALAR)                         \
 315   do                                                          \
 316     {                                                         \
 317       sprintf (pp_buffer (PP)->digit_buffer, FORMAT, SCALAR); \
 318       pp_string (PP, pp_buffer (PP)->digit_buffer);           \
 319     }                                                         \
 320   while (0)
 321 #define pp_decimal_int(PP, I)  pp_scalar (PP, "%d", I)
 322 #define pp_unsigned_wide_integer(PP, I) \
 323    pp_scalar (PP, HOST_WIDE_INT_PRINT_UNSIGNED, (unsigned HOST_WIDE_INT) I)
 324 #define pp_wide_int(PP, W, SGN)                                 \
 325   do                                                            \
 326     {                                                           \
 327       print_dec (W, pp_buffer (PP)->digit_buffer, SGN);         \
 328       pp_string (PP, pp_buffer (PP)->digit_buffer);             \
 329     }                                                           \
 330   while (0)
 331 #define pp_wide_integer(PP, I) \
 332    pp_scalar (PP, HOST_WIDE_INT_PRINT_DEC, (HOST_WIDE_INT) I)
 333 #define pp_pointer(PP, P)      pp_scalar (PP, "%p", P)
 334
 335 #define pp_identifier(PP, ID)  pp_string (PP, (pp_translate_identifiers (PP) \
 336                                           ? identifier_to_locale (ID)   \
 337                                           : (ID)))
 338
 339
 340 #define pp_buffer(PP) (PP)->buffer
 341
 342 extern void pp_set_line_maximum_length (pretty_printer *, int);
 343 extern void pp_set_prefix (pretty_printer *, const char *);
 344 extern void pp_destroy_prefix (pretty_printer *);
 345 extern int pp_remaining_character_count_for_line (pretty_printer *);
 346 extern void pp_clear_output_area (pretty_printer *);
 347 extern const char *pp_formatted_text (pretty_printer *);
 348 extern const char *pp_last_position_in_text (const pretty_printer *);
 349 extern void pp_emit_prefix (pretty_printer *);
 350 extern void pp_append_text (pretty_printer *, const char *, const char *);
 351 extern void pp_newline_and_flush (pretty_printer *);
 352 extern void pp_newline_and_indent (pretty_printer *, int);
 353 extern void pp_separate_with (pretty_printer *, char);
 354
 355 /* If we haven't already defined a front-end-specific diagnostics
 356    style, use the generic one.  */
 357 #ifdef GCC_DIAG_STYLE
 358 #define GCC_PPDIAG_STYLE GCC_DIAG_STYLE
 359 #else
 360 #define GCC_PPDIAG_STYLE __gcc_diag__
 361 #endif
 362
 363 /* This header may be included before diagnostics-core.h, hence the duplicate
 364    definitions to allow for GCC-specific formats.  */
 365 #if GCC_VERSION >= 3005
 366 #define ATTRIBUTE_GCC_PPDIAG(m, n) __attribute__ ((__format__ (GCC_PPDIAG_STYLE, m ,n))) ATTRIBUTE_NONNULL(m)
 367 #else
 368 #define ATTRIBUTE_GCC_PPDIAG(m, n) ATTRIBUTE_NONNULL(m)
 369 #endif
 370 extern void pp_printf (pretty_printer *, const char *, ...)
 371      ATTRIBUTE_GCC_PPDIAG(2,3);
 372
 373 extern void pp_verbatim (pretty_printer *, const char *, ...)
 374      ATTRIBUTE_GCC_PPDIAG(2,3);
 375 extern void pp_flush (pretty_printer *);
 376 extern void pp_really_flush (pretty_printer *);
 377 extern void pp_format (pretty_printer *, text_info *);
 378 extern void pp_output_formatted_text (pretty_printer *);
 379 extern void pp_format_verbatim (pretty_printer *, text_info *);
 380
 381 extern void pp_indent (pretty_printer *);
 382 extern void pp_newline (pretty_printer *);
 383 extern void pp_character (pretty_printer *, int);
 384 extern void pp_string (pretty_printer *, const char *);
 385 extern void pp_write_text_to_stream (pretty_printer *);
 386 extern void pp_write_text_as_dot_label_to_stream (pretty_printer *, bool);
 387 extern void pp_maybe_space (pretty_printer *);
 388
 389 /* Switch into verbatim mode and return the old mode.  */
 390 static inline pp_wrapping_mode_t
 391 pp_set_verbatim_wrapping_ (pretty_printer *pp)
 392 {
 393   pp_wrapping_mode_t oldmode = pp_wrapping_mode (pp);
 394   pp_line_cutoff (pp) = 0;
 395   pp_prefixing_rule (pp) = DIAGNOSTICS_SHOW_PREFIX_NEVER;
 396   return oldmode;
 397 }
 398 #define pp_set_verbatim_wrapping(PP) pp_set_verbatim_wrapping_ (PP)
 399
 400 extern const char *identifier_to_locale (const char *);
 401 extern void *(*identifier_to_locale_alloc) (size_t);
 402 extern void (*identifier_to_locale_free) (void *);
 403
 404 #endif /* GCC_PRETTY_PRINT_H */