pretty-print.h

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/* Various declarations for language-independent pretty-print subroutines.
   Copyright (C) 2002-2024 Free Software Foundation, Inc.
   Contributed by Gabriel Dos Reis <gdr@integrable-solutions.net>
 
This file is part of GCC.
 
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
 
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.
 
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  */
 
#ifndef GCC_PRETTY_PRINT_H
#define GCC_PRETTY_PRINT_H
 
#include "obstack.h"
#include "rich-location.h"
#include "diagnostic-url.h"
 
/* Maximum number of format string arguments.  */
#define PP_NL_ARGMAX   30
 
/* The type of a text to be formatted according a format specification
   along with a list of things.  */
struct text_info
{
  text_info () = default;
  text_info (const char *format_spec,
             va_list *args_ptr,
             int err_no,
             void **data = nullptr,
             rich_location *rich_loc = nullptr)
  : m_format_spec (format_spec),
    m_args_ptr (args_ptr),
    m_err_no (err_no),
    m_data (data),
    m_richloc (rich_loc)
  {
  }
 
  void set_location (unsigned int idx, location_t loc,
                     enum range_display_kind range_display_kind);
  location_t get_location (unsigned int index_of_location) const;
 
  const char *m_format_spec;
  va_list *m_args_ptr;
  int m_err_no;  /* for %m */
  void **m_data;
  rich_location *m_richloc;
};
 
/* How often diagnostics are prefixed by their locations:
   o DIAGNOSTICS_SHOW_PREFIX_NEVER: never - not yet supported;
   o DIAGNOSTICS_SHOW_PREFIX_ONCE: emit only once;
   o DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE: emit each time a physical
   line is started.  */
enum diagnostic_prefixing_rule_t
{
  DIAGNOSTICS_SHOW_PREFIX_ONCE       = 0x0,
  DIAGNOSTICS_SHOW_PREFIX_NEVER      = 0x1,
  DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE = 0x2
};
 
class quoting_info;
class output_buffer;
class urlifier;
 
namespace pp_markup {
  class context;
} // namespace pp_markup
 
/* The chunk_info data structure forms a stack of the results from the
   first phase of formatting (pp_format) which have not yet been
   output (pp_output_formatted_text).  A stack is necessary because
   the diagnostic starter may decide to generate its own output by way
   of the formatter.  */
class chunk_info
{
  friend class pretty_printer;
  friend class pp_markup::context;
 
public:
  const char * const *get_args () const { return m_args; }
  quoting_info *get_quoting_info () const { return m_quotes; }
 
  void append_formatted_chunk (const char *content);
 
  void pop_from_output_buffer (output_buffer &buf);
 
private:
  void on_begin_quote (const output_buffer &buf,
                       unsigned chunk_idx,
                       const urlifier *urlifier);
 
  void on_end_quote (pretty_printer *pp,
                     output_buffer &buf,
                     unsigned chunk_idx,
                     const urlifier *urlifier);
 
  /* Pointer to previous chunk on the stack.  */
  chunk_info *m_prev;
 
  /* Array of chunks to output.  Each chunk is a NUL-terminated string.
     In the first phase of formatting, even-numbered chunks are
     to be output verbatim, odd-numbered chunks are format specifiers.
     The second phase replaces all odd-numbered chunks with formatted
     text, and the third phase simply emits all the chunks in sequence
     with appropriate line-wrapping.  */
  const char *m_args[PP_NL_ARGMAX * 2];
 
  /* If non-null, information on quoted text runs within the chunks
     for use by a urlifier.  */
  quoting_info *m_quotes;
};
 
/* The output buffer datatype.  This is best seen as an abstract datatype
   whose fields should not be accessed directly by clients.  */
class output_buffer
{
public:
  output_buffer ();
  ~output_buffer ();
 
  /* Obstack where the text is built up.  */
  struct obstack formatted_obstack;
 
  /* Obstack containing a chunked representation of the format
     specification plus arguments.  */
  struct obstack chunk_obstack;
 
  /* Currently active obstack: one of the above two.  This is used so
     that the text formatters don't need to know which phase we're in.  */
  struct obstack *obstack;
 
  /* Stack of chunk arrays.  These come from the chunk_obstack.  */
  chunk_info *cur_chunk_array;
 
  /* Where to output formatted text.  */
  FILE *stream;
 
  /* The amount of characters output so far.  */
  int line_length;
 
  /* This must be large enough to hold any printed integer or
     floating-point value.  */
  char digit_buffer[128];
 
  /* Nonzero means that text should be flushed when
     appropriate. Otherwise, text is buffered until either
     pp_really_flush or pp_clear_output_area are called.  */
  bool flush_p;
};
 
/* Finishes constructing a NULL-terminated character string representing
   the buffered text.  */
inline const char *
output_buffer_formatted_text (output_buffer *buff)
{
  obstack_1grow (buff->obstack, '\0');
  return (const char *) obstack_base (buff->obstack);
}
 
/* Append to the output buffer a string specified by its
   STARTing character and LENGTH.  */
inline void
output_buffer_append_r (output_buffer *buff, const char *start, int length)
{
  gcc_checking_assert (start);
  obstack_grow (buff->obstack, start, length);
  for (int i = 0; i < length; i++)
    if (start[i] == '\n')
      buff->line_length = 0;
    else
      buff->line_length++;
}
 
/*  Return a pointer to the last character emitted in the
    output_buffer.  A NULL pointer means no character available.  */
inline const char *
output_buffer_last_position_in_text (const output_buffer *buff)
{
  const char *p = NULL;
  struct obstack *text = buff->obstack;
 
  if (obstack_base (text) != obstack_next_free (text))
    p = ((const char *) obstack_next_free (text)) - 1;
  return p;
}
 
 
/* The type of pretty-printer flags passed to clients.  */
typedef unsigned int pp_flags;
 
enum pp_padding
{
  pp_none, pp_before, pp_after
};
 
/* Structure for switching in and out of verbatim mode in a convenient
   manner.  */
struct pp_wrapping_mode_t
{
  /* Current prefixing rule.  */
  diagnostic_prefixing_rule_t rule;
 
  /* The ideal upper bound of number of characters per line, as suggested
     by front-end.  */
  int line_cutoff;
};
 
/* The type of a hook that formats client-specific data onto a pretty_printer.
   A client-supplied formatter returns true if everything goes well,
   otherwise it returns false.  */
typedef bool (*printer_fn) (pretty_printer *, text_info *, const char *,
                            int, bool, bool, bool, bool *, const char **);
 
/* Base class for an optional client-supplied object for doing additional
   processing between stages 2 and 3 of formatted printing.  */
class format_postprocessor
{
 public:
  virtual ~format_postprocessor () {}
  virtual format_postprocessor *clone() const = 0;
  virtual void handle (pretty_printer *) = 0;
};
 
inline bool & pp_needs_newline (pretty_printer *pp);
 
/* True if PRETTY-PRINTER is in line-wrapping mode.  */
#define pp_is_wrapping_line(PP) (pp_line_cutoff (PP) > 0)
 
inline output_buffer *&pp_buffer (pretty_printer *pp);
inline output_buffer *pp_buffer (const pretty_printer *pp);
inline const char *pp_get_prefix (const pretty_printer *pp);
extern char *pp_take_prefix (pretty_printer *);
extern void pp_destroy_prefix (pretty_printer *);
inline int &pp_line_cutoff (pretty_printer *pp);
inline diagnostic_prefixing_rule_t &pp_prefixing_rule (pretty_printer *pp);
inline pp_wrapping_mode_t &pp_wrapping_mode (pretty_printer *pp);
inline int & pp_indentation (pretty_printer *pp);
inline bool & pp_translate_identifiers (pretty_printer *pp);
inline bool & pp_show_color (pretty_printer *pp);
inline printer_fn &pp_format_decoder (pretty_printer *pp);
inline format_postprocessor *& pp_format_postprocessor (pretty_printer *pp);
inline bool & pp_show_highlight_colors (pretty_printer *pp);
 
class urlifier;
 
/* The data structure that contains the bare minimum required to do
   proper pretty-printing.  Clients may derive from this structure
   and add additional fields they need.  */
class pretty_printer
{
public:
  friend inline output_buffer *&pp_buffer (pretty_printer *pp);
  friend inline output_buffer *pp_buffer (const pretty_printer *pp);
  friend inline const char *pp_get_prefix (const pretty_printer *pp);
  friend char *pp_take_prefix (pretty_printer *);
  friend void pp_destroy_prefix (pretty_printer *);
  friend inline int &pp_line_cutoff (pretty_printer *pp);
  friend inline diagnostic_prefixing_rule_t &
  pp_prefixing_rule (pretty_printer *pp);
  friend inline const diagnostic_prefixing_rule_t &
  pp_prefixing_rule (const pretty_printer *pp);
  friend inline pp_wrapping_mode_t &pp_wrapping_mode (pretty_printer *pp);
  friend bool & pp_needs_newline (pretty_printer *pp);
  friend int & pp_indentation (pretty_printer *pp);
  friend bool & pp_translate_identifiers (pretty_printer *pp);
  friend bool & pp_show_color (pretty_printer *pp);
  friend printer_fn &pp_format_decoder (pretty_printer *pp);
  friend format_postprocessor *& pp_format_postprocessor (pretty_printer *pp);
  friend bool & pp_show_highlight_colors (pretty_printer *pp);
 
  /* Default construct a pretty printer with specified
     maximum line length cut off limit.  */
  explicit pretty_printer (int = 0);
  explicit pretty_printer (const pretty_printer &other);
 
  virtual ~pretty_printer ();
 
  virtual pretty_printer *clone () const;
 
  void set_output_stream (FILE *outfile)
  {
    m_buffer->stream = outfile;
  }
 
  void set_prefix (char *prefix);
 
  void emit_prefix ();
 
  void format (text_info *text,
               const urlifier *urlifier);
 
  void maybe_space ();
 
  bool supports_urls_p () const { return m_url_format != URL_FORMAT_NONE; }
  diagnostic_url_format get_url_format () const { return m_url_format; }
  void set_url_format (diagnostic_url_format url_format)
  {
    m_url_format = url_format;
  }
 
  void begin_url (const char *url);
  void end_url ();
 
  /* Switch into verbatim mode and return the old mode.  */
  pp_wrapping_mode_t
  set_verbatim_wrapping ()
  {
    const pp_wrapping_mode_t oldmode = pp_wrapping_mode (this);
    pp_line_cutoff (this) = 0;
    pp_prefixing_rule (this) = DIAGNOSTICS_SHOW_PREFIX_NEVER;
    return oldmode;
  }
 
  void set_padding (pp_padding padding) { m_padding = padding; }
  pp_padding get_padding () const { return m_padding; }
 
  void clear_state ();
  void set_real_maximum_length ();
  int remaining_character_count_for_line ();
 
private:
  /* Where we print external representation of ENTITY.  */
  output_buffer *m_buffer;
 
  /* The prefix for each new line.  If non-NULL, this is "owned" by the
     pretty_printer, and will eventually be free-ed.  */
  char *m_prefix;
 
  /* Where to put whitespace around the entity being formatted.  */
  pp_padding m_padding;
 
  /* The real upper bound of number of characters per line, taking into
     account the case of a very very looong prefix.  */
  int m_maximum_length;
 
  /* Indentation count.  */
  int m_indent_skip;
 
  /* Current wrapping mode.  */
  pp_wrapping_mode_t m_wrapping;
 
  /* If non-NULL, this function formats a TEXT into the BUFFER.  When called,
     TEXT->format_spec points to a format code.  FORMAT_DECODER should call
     pp_string (and related functions) to add data to the BUFFER.
     FORMAT_DECODER can read arguments from *TEXT->args_pts using VA_ARG.
     If the BUFFER needs additional characters from the format string, it
     should advance the TEXT->format_spec as it goes.  When FORMAT_DECODER
     returns, TEXT->format_spec should point to the last character processed.
     The QUOTE and BUFFER_PTR are passed in, to allow for deferring-handling
     of format codes (e.g. %H and %I in the C++ frontend).  */
  printer_fn m_format_decoder;
 
  /* If non-NULL, this is called by pp_format once after all format codes
     have been processed, to allow for client-specific postprocessing.
     This is used by the C++ frontend for handling the %H and %I
     format codes (which interract with each other).  */
  format_postprocessor *m_format_postprocessor;
 
  /* Nonzero if current PREFIX was emitted at least once.  */
  bool m_emitted_prefix;
 
  /* Nonzero means one should emit a newline before outputting anything.  */
  bool m_need_newline;
 
  /* Nonzero means identifiers are translated to the locale character
     set on output.  */
  bool m_translate_identifiers;
 
  /* Nonzero means that text should be colorized.  */
  bool m_show_color;
 
  /* True means that pertinent sections within the text should be
     highlighted with color.  */
  bool m_show_highlight_colors;
 
  /* Whether URLs should be emitted, and which terminator to use.  */
  diagnostic_url_format m_url_format;
 
  /* If true, then we've had a begin_url (nullptr), and so the
     next end_url should be a no-op.  */
  bool m_skipping_null_url;
};
 
inline output_buffer *&
pp_buffer (pretty_printer *pp)
{
  return pp->m_buffer;
}
 
inline output_buffer *
pp_buffer (const pretty_printer *pp)
{
  return pp->m_buffer;
}
 
inline const char *
pp_get_prefix (const pretty_printer *pp)
{
  return pp->m_prefix;
}
 
/* TRUE if a newline character needs to be added before further
   formatting.  */
inline bool &
pp_needs_newline (pretty_printer *pp)
{
  return pp->m_need_newline;
}
 
/* The amount of whitespace to be emitted when starting a new line.  */
inline int &
pp_indentation (pretty_printer *pp)
{
  return pp->m_indent_skip;
}
 
/* True if identifiers are translated to the locale character set on
   output.  */
inline bool &
pp_translate_identifiers (pretty_printer *pp)
{
  return pp->m_translate_identifiers;
}
 
/* True if colors should be shown.  */
inline bool &
pp_show_color (pretty_printer *pp)
{
  return pp->m_show_color;
}
 
inline printer_fn &
pp_format_decoder (pretty_printer *pp)
{
  return pp->m_format_decoder;
}
 
inline format_postprocessor *&
pp_format_postprocessor (pretty_printer *pp)
{
  return pp->m_format_postprocessor;
}
 
inline bool &
pp_show_highlight_colors (pretty_printer *pp)
{
  return pp->m_show_highlight_colors;
}
 
/* Maximum characters per line in automatic line wrapping mode.
   Zero means don't wrap lines.  */
inline int &
pp_line_cutoff (pretty_printer *pp)
{
  return pp->m_wrapping.line_cutoff;
}
 
/* Prefixing rule used in formatting a diagnostic message.  */
inline diagnostic_prefixing_rule_t &
pp_prefixing_rule (pretty_printer *pp)
{
  return pp->m_wrapping.rule;
}
inline const diagnostic_prefixing_rule_t &
pp_prefixing_rule (const pretty_printer *pp)
{
  return pp->m_wrapping.rule;
}
 
/* Get or set the wrapping mode as a single entity.  */
inline pp_wrapping_mode_t &
pp_wrapping_mode (pretty_printer *pp)
{
  return pp->m_wrapping;
}
 
#define pp_space(PP)            pp_character (PP, ' ')
#define pp_left_paren(PP)       pp_character (PP, '(')
#define pp_right_paren(PP)      pp_character (PP, ')')
#define pp_left_bracket(PP)     pp_character (PP, '[')
#define pp_right_bracket(PP)    pp_character (PP, ']')
#define pp_left_brace(PP)       pp_character (PP, '{')
#define pp_right_brace(PP)      pp_character (PP, '}')
#define pp_semicolon(PP)        pp_character (PP, ';')
#define pp_comma(PP)            pp_character (PP, ',')
#define pp_dot(PP)              pp_character (PP, '.')
#define pp_colon(PP)            pp_character (PP, ':')
#define pp_colon_colon(PP)      pp_string (PP, "::")
#define pp_arrow(PP)            pp_string (PP, "->")
#define pp_equal(PP)            pp_character (PP, '=')
#define pp_question(PP)         pp_character (PP, '?')
#define pp_bar(PP)              pp_character (PP, '|')
#define pp_bar_bar(PP)          pp_string (PP, "||")
#define pp_carret(PP)           pp_character (PP, '^')
#define pp_ampersand(PP)        pp_character (PP, '&')
#define pp_ampersand_ampersand(PP) pp_string (PP, "&&")
#define pp_less(PP)             pp_character (PP, '<')
#define pp_less_equal(PP)       pp_string (PP, "<=")
#define pp_greater(PP)          pp_character (PP, '>')
#define pp_greater_equal(PP)    pp_string (PP, ">=")
#define pp_plus(PP)             pp_character (PP, '+')
#define pp_minus(PP)            pp_character (PP, '-')
#define pp_star(PP)             pp_character (PP, '*')
#define pp_slash(PP)            pp_character (PP, '/')
#define pp_modulo(PP)           pp_character (PP, '%')
#define pp_exclamation(PP)      pp_character (PP, '!')
#define pp_complement(PP)       pp_character (PP, '~')
#define pp_quote(PP)            pp_character (PP, '\'')
#define pp_backquote(PP)        pp_character (PP, '`')
#define pp_doublequote(PP)      pp_character (PP, '"')
#define pp_underscore(PP)       pp_character (PP, '_')
#define pp_maybe_newline_and_indent(PP, N) \
  if (pp_needs_newline (PP)) pp_newline_and_indent (PP, N)
#define pp_scalar(PP, FORMAT, SCALAR)                         \
  do                                                          \
    {                                                         \
      sprintf (pp_buffer (PP)->digit_buffer, FORMAT, SCALAR); \
      pp_string (PP, pp_buffer (PP)->digit_buffer);           \
    }                                                         \
  while (0)
#define pp_decimal_int(PP, I)  pp_scalar (PP, "%d", I)
#define pp_unsigned_wide_integer(PP, I) \
   pp_scalar (PP, HOST_WIDE_INT_PRINT_UNSIGNED, (unsigned HOST_WIDE_INT) I)
#define pp_vrange(PP, R)                                        \
  do                                                            \
    {                                                           \
      vrange_printer vrange_pp (PP);                            \
      (R)->accept (vrange_pp);                                  \
    }                                                           \
  while (0)
#define pp_double(PP, F)       pp_scalar (PP, "%f", F)
#define pp_pointer(PP, P)      pp_scalar (PP, "%p", P)
 
#define pp_identifier(PP, ID)  pp_string (PP, (pp_translate_identifiers (PP) \
                                          ? identifier_to_locale (ID)   \
                                          : (ID)))
 
 
extern void pp_set_line_maximum_length (pretty_printer *, int);
inline void pp_set_prefix (pretty_printer *pp, char *prefix)
{
  pp->set_prefix (prefix);
}
extern void pp_clear_output_area (pretty_printer *);
extern const char *pp_formatted_text (pretty_printer *);
extern const char *pp_last_position_in_text (const pretty_printer *);
inline void pp_emit_prefix (pretty_printer *pp)
{
  pp->emit_prefix ();
}
extern void pp_append_text (pretty_printer *, const char *, const char *);
extern void pp_newline_and_flush (pretty_printer *);
extern void pp_newline_and_indent (pretty_printer *, int);
extern void pp_separate_with (pretty_printer *, char);
 
/* If we haven't already defined a front-end-specific diagnostics
   style, use the generic one.  */
#ifdef GCC_DIAG_STYLE
#define GCC_PPDIAG_STYLE GCC_DIAG_STYLE
#else
#define GCC_PPDIAG_STYLE __gcc_diag__
#endif
 
/* This header may be included before diagnostics-core.h, hence the duplicate
   definitions to allow for GCC-specific formats.  */
#if GCC_VERSION >= 3005
#define ATTRIBUTE_GCC_PPDIAG(m, n) __attribute__ ((__format__ (GCC_PPDIAG_STYLE, m ,n))) ATTRIBUTE_NONNULL(m)
#else
#define ATTRIBUTE_GCC_PPDIAG(m, n) ATTRIBUTE_NONNULL(m)
#endif
extern void pp_printf (pretty_printer *, const char *, ...)
     ATTRIBUTE_GCC_PPDIAG(2,3);
 
extern void pp_verbatim (pretty_printer *, const char *, ...)
     ATTRIBUTE_GCC_PPDIAG(2,3);
extern void pp_flush (pretty_printer *);
extern void pp_really_flush (pretty_printer *);
inline void pp_format (pretty_printer *pp, text_info *text,
                       const urlifier *urlifier = nullptr)
{
  pp->format (text, urlifier);
}
extern void pp_output_formatted_text (pretty_printer *,
                                      const urlifier * = nullptr);
extern void pp_format_verbatim (pretty_printer *, text_info *);
 
extern void pp_indent (pretty_printer *);
extern void pp_newline (pretty_printer *);
extern void pp_character (pretty_printer *, int);
extern void pp_string (pretty_printer *, const char *);
extern void pp_string_n (pretty_printer *, const char *, size_t);
extern void pp_unicode_character (pretty_printer *, unsigned);
 
extern void pp_write_text_to_stream (pretty_printer *);
extern void pp_write_text_as_dot_label_to_stream (pretty_printer *, bool);
extern void pp_write_text_as_html_like_dot_to_stream (pretty_printer *pp);
 
inline void pp_maybe_space (pretty_printer *pp)
{
  pp->maybe_space ();
}
 
extern void pp_begin_quote (pretty_printer *, bool);
extern void pp_end_quote (pretty_printer *, bool);
 
inline void
pp_begin_url (pretty_printer *pp, const char *url)
{
  pp->begin_url (url);
}
 
inline void
pp_end_url (pretty_printer *pp)
{
  pp->end_url ();
}
 
/* Switch into verbatim mode and return the old mode.  */
inline pp_wrapping_mode_t
pp_set_verbatim_wrapping (pretty_printer *pp)
{
  return pp->set_verbatim_wrapping ();
}
 
extern const char *identifier_to_locale (const char *);
extern void *(*identifier_to_locale_alloc) (size_t);
extern void (*identifier_to_locale_free) (void *);
 
/* Print I to PP in decimal.  */
 
inline void
pp_wide_integer (pretty_printer *pp, HOST_WIDE_INT i)
{
  pp_scalar (pp, HOST_WIDE_INT_PRINT_DEC, i);
}
 
inline void
pp_wide_int (pretty_printer *pp, const wide_int_ref &w, signop sgn)
{
  unsigned int len;
  print_dec_buf_size (w, sgn, &len);
  if (UNLIKELY (len > sizeof (pp_buffer (pp)->digit_buffer)))
    pp_wide_int_large (pp, w, sgn);
  else
    {
      print_dec (w, pp_buffer (pp)->digit_buffer, sgn);
      pp_string (pp, pp_buffer (pp)->digit_buffer);
    }
}
 
template<unsigned int N, typename T>
void pp_wide_integer (pretty_printer *pp, const poly_int<N, T> &);
 
#endif /* GCC_PRETTY_PRINT_H */