dist/gcc/diagnostic.h

/* Various declarations for language-independent diagnostics subroutines.
   Copyright (C) 2000-2022 Free Software Foundation, Inc.
   Contributed by Gabriel Dos Reis <gdr (at) codesourcery.com>

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_DIAGNOSTIC_H
#define GCC_DIAGNOSTIC_H

#include "pretty-print.h"
#include "diagnostic-core.h"

/* An enum for controlling what units to use for the column number
   when diagnostics are output, used by the -fdiagnostics-column-unit option.
   Tabs will be expanded or not according to the value of -ftabstop.  The origin
   (default 1) is controlled by -fdiagnostics-column-origin.  */

enum diagnostics_column_unit
{
  /* The default from GCC 11 onwards: display columns.  */
  DIAGNOSTICS_COLUMN_UNIT_DISPLAY,

  /* The behavior in GCC 10 and earlier: simple bytes.  */
  DIAGNOSTICS_COLUMN_UNIT_BYTE
};

/* An enum for controlling how to print non-ASCII characters/bytes when
   a diagnostic suggests escaping the source code on output.  */

enum diagnostics_escape_format
{
  /* Escape non-ASCII Unicode characters in the form <U+XXXX> and
     non-UTF-8 bytes in the form <XX>.  */
  DIAGNOSTICS_ESCAPE_FORMAT_UNICODE,

  /* Escape non-ASCII bytes in the form <XX> (thus showing the underlying
     encoding of non-ASCII Unicode characters).  */
  DIAGNOSTICS_ESCAPE_FORMAT_BYTES
};

/* Enum for overriding the standard output format.  */

enum diagnostics_output_format
{
  /* The default: textual output.  */
  DIAGNOSTICS_OUTPUT_FORMAT_TEXT,

  /* JSON-based output.  */
  DIAGNOSTICS_OUTPUT_FORMAT_JSON
};

/* An enum for controlling how diagnostic_paths should be printed.  */
enum diagnostic_path_format
{
  /* Don't print diagnostic_paths.  */
  DPF_NONE,

  /* Print diagnostic_paths by emitting a separate "note" for every event
     in the path.  */
  DPF_SEPARATE_EVENTS,

  /* Print diagnostic_paths by consolidating events together where they
     are close enough, and printing such runs of events with multiple
     calls to diagnostic_show_locus, showing the individual events in
     each run via labels in the source.  */
  DPF_INLINE_EVENTS
};

/* An enum for capturing values of GCC_EXTRA_DIAGNOSTIC_OUTPUT,
   and for -fdiagnostics-parseable-fixits.  */

enum diagnostics_extra_output_kind
{
  /* No extra output, or an unrecognized value.  */
  EXTRA_DIAGNOSTIC_OUTPUT_none,

  /* Emit fix-it hints using the "fixits-v1" format, equivalent to
     -fdiagnostics-parseable-fixits.  */
  EXTRA_DIAGNOSTIC_OUTPUT_fixits_v1,

  /* Emit fix-it hints using the "fixits-v2" format.  */
  EXTRA_DIAGNOSTIC_OUTPUT_fixits_v2
};

/* A diagnostic is described by the MESSAGE to send, the FILE and LINE of
   its context and its KIND (ice, error, warning, note, ...)  See complete
   list in diagnostic.def.  */
struct diagnostic_info
{
  diagnostic_info ()
    : message (), richloc (), metadata (), x_data (), kind (), option_index (),
      m_iinfo ()
  { }

  /* Text to be formatted.  */
  text_info message;

  /* The location at which the diagnostic is to be reported.  */
  rich_location *richloc;

  /* An optional bundle of metadata associated with the diagnostic
     (or NULL).  */
  const diagnostic_metadata *metadata;

  /* Auxiliary data for client.  */
  void *x_data;
  /* The kind of diagnostic it is about.  */
  diagnostic_t kind;
  /* Which OPT_* directly controls this diagnostic.  */
  int option_index;

  /* Inlining context containing locations for each call site along
     the inlining stack.  */
  struct inlining_info
  {
    /* Locations along the inlining stack.  */
    auto_vec<location_t, 8> m_ilocs;
    /* The abstract origin of the location.  */
    void *m_ao;
    /* Set if every M_ILOCS element is in a system header.  */
    bool m_allsyslocs;
  } m_iinfo;
};

/* Each time a diagnostic's classification is changed with a pragma,
   we record the change and the location of the change in an array of
   these structs.  */
struct diagnostic_classification_change_t
{
  location_t location;
  int option;
  diagnostic_t kind;
};

/*  Forward declarations.  */
typedef void (*diagnostic_starter_fn) (diagnostic_context *,
				       diagnostic_info *);

typedef void (*diagnostic_start_span_fn) (diagnostic_context *,
					  expanded_location);

typedef void (*diagnostic_finalizer_fn) (diagnostic_context *,
					 diagnostic_info *,
					 diagnostic_t);

class edit_context;
namespace json { class value; }

/* This data structure bundles altogether any information relevant to
   the context of a diagnostic message.  */
struct diagnostic_context
{
  /* Where most of the diagnostic formatting work is done.  */
  pretty_printer *printer;

  /* Cache of source code.  */
  file_cache *m_file_cache;

  /* The number of times we have issued diagnostics.  */
  int diagnostic_count[DK_LAST_DIAGNOSTIC_KIND];

  /* True if it has been requested that warnings be treated as errors.  */
  bool warning_as_error_requested;

  /* The number of option indexes that can be passed to warning() et
     al.  */
  int n_opts;

  /* For each option index that can be passed to warning() et al
     (OPT_* from options.h when using this code with the core GCC
     options), this array may contain a new kind that the diagnostic
     should be changed to before reporting, or DK_UNSPECIFIED to leave
     it as the reported kind, or DK_IGNORED to not report it at
     all.  */
  diagnostic_t *classify_diagnostic;

  /* History of all changes to the classifications above.  This list
     is stored in location-order, so we can search it, either
     binary-wise or end-to-front, to find the most recent
     classification for a given diagnostic, given the location of the
     diagnostic.  */
  diagnostic_classification_change_t *classification_history;

  /* The size of the above array.  */
  int n_classification_history;

  /* For pragma push/pop.  */
  int *push_list;
  int n_push;

  /* True if we should print the source line with a caret indicating
     the location.  */
  bool show_caret;

  /* Maximum width of the source line printed.  */
  int caret_max_width;

  /* Character used for caret diagnostics.  */
  char caret_chars[rich_location::STATICALLY_ALLOCATED_RANGES];

  /* True if we should print any CWE identifiers associated with
     diagnostics.  */
  bool show_cwe;

  /* How should diagnostic_path objects be printed.  */
  enum diagnostic_path_format path_format;

  /* True if we should print stack depths when printing diagnostic paths.  */
  bool show_path_depths;

  /* True if we should print the command line option which controls
     each diagnostic, if known.  */
  bool show_option_requested;

  /* True if we should raise a SIGABRT on errors.  */
  bool abort_on_error;

  /* True if we should show the column number on diagnostics.  */
  bool show_column;

  /* True if pedwarns are errors.  */
  bool pedantic_errors;

  /* True if permerrors are warnings.  */
  bool permissive;

  /* The index of the option to associate with turning permerrors into
     warnings.  */
  int opt_permissive;

  /* True if errors are fatal.  */
  bool fatal_errors;

  /* True if all warnings should be disabled.  */
  bool dc_inhibit_warnings;

  /* True if warnings should be given in system headers.  */
  bool dc_warn_system_headers;

  /* Maximum number of errors to report.  */
  int max_errors;

  /* This function is called before any message is printed out.  It is
     responsible for preparing message prefix and such.  For example, it
     might say:
     In file included from "/usr/local/include/curses.h:5:
                      from "/home/gdr/src/nifty_printer.h:56:
                      ...
  */
  diagnostic_starter_fn begin_diagnostic;

  /* This function is called by diagnostic_show_locus in between
     disjoint spans of source code, so that the context can print
     something to indicate that a new span of source code has begun.  */
  diagnostic_start_span_fn start_span;

  /* This function is called after the diagnostic message is printed.  */
  diagnostic_finalizer_fn end_diagnostic;

  /* Client hook to report an internal error.  */
  void (*internal_error) (diagnostic_context *, const char *, va_list *);

  /* Client hook to say whether the option controlling a diagnostic is
     enabled.  Returns nonzero if enabled, zero if disabled.  */
  int (*option_enabled) (int, unsigned, void *);

  /* Client information to pass as second argument to
     option_enabled.  */
  void *option_state;

  /* Client hook to return the name of an option that controls a
     diagnostic.  Returns malloced memory.  The first diagnostic_t
     argument is the kind of diagnostic before any reclassification
     (of warnings as errors, etc.); the second is the kind after any
     reclassification.  May return NULL if no name is to be printed.
     May be passed 0 as well as the index of a particular option.  */
  char *(*option_name) (diagnostic_context *, int, diagnostic_t, diagnostic_t);

  /* Client hook to return a URL describing the option that controls
     a diagnostic.  Returns malloced memory.  May return NULL if no URL
     is available.  May be passed 0 as well as the index of a
     particular option.  */
  char *(*get_option_url) (diagnostic_context *, int);

  void (*print_path) (diagnostic_context *, const diagnostic_path *);
  json::value *(*make_json_for_path) (diagnostic_context *, const diagnostic_path *);

  /* Auxiliary data for client.  */
  void *x_data;

  /* Used to detect that the last caret was printed at the same location.  */
  location_t last_location;

  /* Used to detect when the input file stack has changed since last
     described.  */
  const line_map_ordinary *last_module;

  int lock;

  /* A copy of lang_hooks.option_lang_mask ().  */
  unsigned lang_mask;

  bool inhibit_notes_p;

  /* When printing source code, should the characters at carets and ranges
     be colorized? (assuming colorization is on at all).
     This should be true for frontends that generate range information
     (so that the ranges of code are colorized),
     and false for frontends that merely specify points within the
     source code (to avoid e.g. colorizing just the first character in
     a token, which would look strange).  */
  bool colorize_source_p;

  /* When printing source code, should labelled ranges be printed?  */
  bool show_labels_p;

  /* When printing source code, should there be a left-hand margin
     showing line numbers?  */
  bool show_line_numbers_p;

  /* If printing source code, what should the minimum width of the margin
     be?  Line numbers will be right-aligned, and padded to this width.  */
  int min_margin_width;

  /* Usable by plugins; if true, print a debugging ruler above the
     source output.  */
  bool show_ruler_p;

  /* True if -freport-bug option is used.  */
  bool report_bug;

  /* Used to specify additional diagnostic output to be emitted after the
     rest of the diagnostic.  This is for implementing
     -fdiagnostics-parseable-fixits and GCC_EXTRA_DIAGNOSTIC_OUTPUT.  */
  enum diagnostics_extra_output_kind extra_output_kind;

  /* What units to use when outputting the column number.  */
  enum diagnostics_column_unit column_unit;

  /* The origin for the column number (1-based or 0-based typically).  */
  int column_origin;

  /* The size of the tabstop for tab expansion.  */
  int tabstop;

  /* How should non-ASCII/non-printable bytes be escaped when
     a diagnostic suggests escaping the source code on output.  */
  enum diagnostics_escape_format escape_format;

  /* If non-NULL, an edit_context to which fix-it hints should be
     applied, for generating patches.  */
  edit_context *edit_context_ptr;

  /* How many diagnostic_group instances are currently alive.  */
  int diagnostic_group_nesting_depth;

  /* How many diagnostics have been emitted since the bottommost
     diagnostic_group was pushed.  */
  int diagnostic_group_emission_count;

  /* Optional callbacks for handling diagnostic groups.  */

  /* If non-NULL, this will be called immediately before the first
     time a diagnostic is emitted within a stack of groups.  */
  void (*begin_group_cb) (diagnostic_context * context);

  /* If non-NULL, this will be called when a stack of groups is
     popped if any diagnostics were emitted within that group.  */
  void (*end_group_cb) (diagnostic_context * context);

  /* Callback for final cleanup.  */
  void (*final_cb) (diagnostic_context *context);

  /* Callback to set the locations of call sites along the inlining
     stack corresponding to a diagnostic location.  Needed to traverse
     the BLOCK_SUPERCONTEXT() chain hanging off the LOCATION_BLOCK()
     of a diagnostic's location.  */
  void (*set_locations_cb)(diagnostic_context *, diagnostic_info *);

  /* Include files that diagnostic_report_current_module has already listed the
     include path for.  */
  hash_set<location_t, false, location_hash> *includes_seen;
};

static inline void
diagnostic_inhibit_notes (diagnostic_context * context)
{
  context->inhibit_notes_p = true;
}


/* Client supplied function to announce a diagnostic.  */
#define diagnostic_starter(DC) (DC)->begin_diagnostic

/* Client supplied function called after a diagnostic message is
   displayed.  */
#define diagnostic_finalizer(DC) (DC)->end_diagnostic

/* Extension hooks for client.  */
#define diagnostic_context_auxiliary_data(DC) (DC)->x_data
#define diagnostic_info_auxiliary_data(DI) (DI)->x_data

/* Same as pp_format_decoder.  Works on 'diagnostic_context *'.  */
#define diagnostic_format_decoder(DC) ((DC)->printer->format_decoder)

/* Same as output_prefixing_rule.  Works on 'diagnostic_context *'.  */
#define diagnostic_prefixing_rule(DC) ((DC)->printer->wrapping.rule)

/* Raise SIGABRT on any diagnostic of severity DK_ERROR or higher.  */
#define diagnostic_abort_on_error(DC) \
  (DC)->abort_on_error = true

/* This diagnostic_context is used by front-ends that directly output
   diagnostic messages without going through `error', `warning',
   and similar functions.  */
extern diagnostic_context *global_dc;

/* Returns whether the diagnostic framework has been intialized already and is
   ready for use.  */
#define diagnostic_ready_p() (global_dc->printer != NULL)

/* The total count of a KIND of diagnostics emitted so far.  */
#define diagnostic_kind_count(DC, DK) (DC)->diagnostic_count[(int) (DK)]

/* The number of errors that have been issued so far.  Ideally, these
   would take a diagnostic_context as an argument.  */
#define errorcount diagnostic_kind_count (global_dc, DK_ERROR)
/* Similarly, but for warnings.  */
#define warningcount diagnostic_kind_count (global_dc, DK_WARNING)
/* Similarly, but for warnings promoted to errors.  */
#define werrorcount diagnostic_kind_count (global_dc, DK_WERROR)
/* Similarly, but for sorrys.  */
#define sorrycount diagnostic_kind_count (global_dc, DK_SORRY)

/* Returns nonzero if warnings should be emitted.  */
#define diagnostic_report_warnings_p(DC, LOC)				\
  (!(DC)->dc_inhibit_warnings						\
   && !(in_system_header_at (LOC) && !(DC)->dc_warn_system_headers))

/* Override the option index to be used for reporting a
   diagnostic.  */

static inline void
diagnostic_override_option_index (diagnostic_info *info, int optidx)
{
  info->option_index = optidx;
}

/* Diagnostic related functions.  */
extern void diagnostic_initialize (diagnostic_context *, int);
extern void diagnostic_color_init (diagnostic_context *, int value = -1);
extern void diagnostic_urls_init (diagnostic_context *, int value = -1);
extern void diagnostic_finish (diagnostic_context *);
extern void diagnostic_report_current_module (diagnostic_context *, location_t);
extern void diagnostic_show_locus (diagnostic_context *,
				   rich_location *richloc,
				   diagnostic_t diagnostic_kind);
extern void diagnostic_show_any_path (diagnostic_context *, diagnostic_info *);

/* Because we read source files a second time after the frontend did it the
   first time, we need to know how the frontend handled things like character
   set conversion and UTF-8 BOM stripping, in order to make everything
   consistent.  This function needs to be called by each frontend that requires
   non-default behavior, to inform the diagnostics infrastructure how input is
   to be processed.  The default behavior is to do no conversion and not to
   strip a UTF-8 BOM.

   The callback should return the input charset to be used to convert the given
   file's contents to UTF-8, or it should return NULL if no conversion is needed
   for this file.  SHOULD_SKIP_BOM only applies in case no conversion was
   performed, and if true, it will cause a UTF-8 BOM to be skipped at the
   beginning of the file.  (In case a conversion was performed, the BOM is
   rather skipped as part of the conversion process.)  */

void diagnostic_initialize_input_context (diagnostic_context *context,
					  diagnostic_input_charset_callback ccb,
					  bool should_skip_bom);

/* Force diagnostics controlled by OPTIDX to be kind KIND.  */
extern diagnostic_t diagnostic_classify_diagnostic (diagnostic_context *,
						    int /* optidx */,
						    diagnostic_t /* kind */,
						    location_t);
extern void diagnostic_push_diagnostics (diagnostic_context *, location_t);
extern void diagnostic_pop_diagnostics (diagnostic_context *, location_t);
extern bool diagnostic_report_diagnostic (diagnostic_context *,
					  diagnostic_info *);
#ifdef ATTRIBUTE_GCC_DIAG
extern void diagnostic_set_info (diagnostic_info *, const char *, va_list *,
				 rich_location *, diagnostic_t) ATTRIBUTE_GCC_DIAG(2,0);
extern void diagnostic_set_info_translated (diagnostic_info *, const char *,
					    va_list *, rich_location *,
					    diagnostic_t)
     ATTRIBUTE_GCC_DIAG(2,0);
extern void diagnostic_append_note (diagnostic_context *, location_t,
                                    const char *, ...) ATTRIBUTE_GCC_DIAG(3,4);
#endif
extern char *diagnostic_build_prefix (diagnostic_context *, const diagnostic_info *);
void default_diagnostic_starter (diagnostic_context *, diagnostic_info *);
void default_diagnostic_start_span_fn (diagnostic_context *,
				       expanded_location);
void default_diagnostic_finalizer (diagnostic_context *, diagnostic_info *,
				   diagnostic_t);
void diagnostic_set_caret_max_width (diagnostic_context *context, int value);
void diagnostic_action_after_output (diagnostic_context *, diagnostic_t);
void diagnostic_check_max_errors (diagnostic_context *, bool flush = false);

void diagnostic_file_cache_fini (void);

int get_terminal_width (void);

/* Return the location associated to this diagnostic. Parameter WHICH
   specifies which location. By default, expand the first one.  */

static inline location_t
diagnostic_location (const diagnostic_info * diagnostic, int which = 0)
{
  return diagnostic->message.get_location (which);
}

/* Return the number of locations to be printed in DIAGNOSTIC.  */

static inline unsigned int
diagnostic_num_locations (const diagnostic_info * diagnostic)
{
  return diagnostic->message.m_richloc->get_num_locations ();
}

/* Expand the location of this diagnostic. Use this function for
   consistency.  Parameter WHICH specifies which location. By default,
   expand the first one.  */

static inline expanded_location
diagnostic_expand_location (const diagnostic_info * diagnostic, int which = 0)
{
  return diagnostic->richloc->get_expanded_location (which);
}

/* This is somehow the right-side margin of a caret line, that is, we
   print at least these many characters after the position pointed at
   by the caret.  */
const int CARET_LINE_MARGIN = 10;

/* Return true if the two locations can be represented within the same
   caret line.  This is used to build a prefix and also to determine
   whether to print one or two caret lines.  */

static inline bool
diagnostic_same_line (const diagnostic_context *context,
		       expanded_location s1, expanded_location s2)
{
  return s2.column && s1.line == s2.line
    && context->caret_max_width - CARET_LINE_MARGIN > abs (s1.column - s2.column);
}

extern const char *diagnostic_get_color_for_kind (diagnostic_t kind);
extern int diagnostic_converted_column (diagnostic_context *context,
					expanded_location s);

/* Pure text formatting support functions.  */
extern char *file_name_as_prefix (diagnostic_context *, const char *);

extern char *build_message_string (const char *, ...) ATTRIBUTE_PRINTF_1;

extern void diagnostic_output_format_init (diagnostic_context *,
					   enum diagnostics_output_format);

/* Compute the number of digits in the decimal representation of an integer.  */
extern int num_digits (int);

extern json::value *json_from_expanded_location (diagnostic_context *context,
						 location_t loc);

extern bool warning_enabled_at (location_t, int);

#endif /* ! GCC_DIAGNOSTIC_H */