libcpp/include/line-map.h

   1 /* Map logical line numbers to (source file, line number) pairs.
   2    Copyright (C) 2001, 2003, 2004
   3    Free Software Foundation, Inc.
   4
   5 This program is free software; you can redistribute it and/or modify it
   6 under the terms of the GNU General Public License as published by the
   7 Free Software Foundation; either version 2, or (at your option) any
   8 later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18
  19  In other words, you are welcome to use, share and improve this program.
  20  You are forbidden to forbid anyone else to use, share and improve
  21  what you give them.   Help stamp out software-hoarding!  */
  22
  23 #ifndef LIBCPP_LINE_MAP_H
  24 #define LIBCPP_LINE_MAP_H
  25
  26 /* Reason for adding a line change with add_line_map ().  LC_ENTER is
  27    when including a new file, e.g. a #include directive in C.
  28    LC_LEAVE is when reaching a file's end.  LC_RENAME is when a file
  29    name or line number changes for neither of the above reasons
  30    (e.g. a #line directive in C).  */
  31 enum lc_reason {LC_ENTER = 0, LC_LEAVE, LC_RENAME};
  32
  33 /* A logical line/column number, i.e. an "index" into a line_map.  */
  34 /* Long-term, we want to use this to replace struct location_s (in input.h),
  35    and effectively typedef source_location location_t.  */
  36 typedef unsigned int source_location;
  37
  38 /* Physical source file TO_FILE at line TO_LINE at column 0 is represented
  39    by the logical START_LOCATION.  TO_LINE+L at column C is represented by
  40    START_LOCATION+(L*(1<<column_bits))+C, as long as C<(1<<column_bits),
  41    and the result_location is less than the next line_map's start_location.
  42    (The top line is line 1 and the leftmost column is column 1; line/column 0
  43    means "entire file/line" or "unknown line/column" or "not applicable".)
  44    INCLUDED_FROM is an index into the set that gives the line mapping
  45    at whose end the current one was included.  File(s) at the bottom
  46    of the include stack have this set to -1.  REASON is the reason for
  47    creation of this line map, SYSP is one for a system header, two for
  48    a C system header file that therefore needs to be extern "C"
  49    protected in C++, and zero otherwise.  */
  50 struct line_map
  51 {
  52   const char *to_file;
  53   unsigned int to_line;
  54   source_location start_location;
  55   int included_from;
  56   ENUM_BITFIELD (lc_reason) reason : CHAR_BIT;
  57   /* The sysp field isn't really needed now that it's in cpp_buffer.  */
  58   unsigned char sysp;
  59   /* Number of the low-order source_location bits used for a column number.  */
  60   unsigned int column_bits : 8;
  61 };
  62
  63 /* A set of chronological line_map structures.  */
  64 struct line_maps
  65 {
  66   struct line_map *maps;
  67   unsigned int allocated;
  68   unsigned int used;
  69
  70   unsigned int cache;
  71
  72   /* The most recently listed include stack, if any, starts with
  73      LAST_LISTED as the topmost including file.  -1 indicates nothing
  74      has been listed yet.  */
  75   int last_listed;
  76
  77   /* Depth of the include stack, including the current file.  */
  78   unsigned int depth;
  79
  80   /* If true, prints an include trace a la -H.  */
  81   bool trace_includes;
  82
  83   /* Highest source_location "given out".  */
  84   source_location highest_location;
  85
  86   /* Start of line of highest source_location "given out".  */
  87   source_location highest_line;
  88
  89   /* The maximum column number we can quickly allocate.  Higher numbers
  90      may require allocating a new line_map.  */
  91   unsigned int max_column_hint;
  92 };
  93
  94 /* Initialize a line map set.  */
  95 extern void linemap_init (struct line_maps *);
  96
  97 /* Free a line map set.  */
  98 extern void linemap_free (struct line_maps *);
  99
 100 /* Check for and warn about line_maps entered but not exited.  */
 101
 102 extern void linemap_check_files_exited (struct line_maps *);
 103
 104 /* Return a source_location for the start (i.e. column==0) of
 105    (physical) line TO_LINE in the current source file (as in the
 106    most recent linemap_add).   MAX_COLUMN_HINT is the highest column
 107    number we expect to use in this line (but it does not change
 108    the highest_location).  */
 109
 110 extern source_location linemap_line_start
 111 (struct line_maps *, unsigned int,  unsigned int);
 112
 113 /* Add a mapping of logical source line to physical source file and
 114    line number.
 115
 116    The text pointed to by TO_FILE must have a lifetime
 117    at least as long as the final call to lookup_line ().  An empty
 118    TO_FILE means standard input.  If reason is LC_LEAVE, and
 119    TO_FILE is NULL, then TO_FILE, TO_LINE and SYSP are given their
 120    natural values considering the file we are returning to.
 121
 122    START_LOCATION should be monotonic increasing across calls to this
 123    function.  A call to this function can relocate the previous set of
 124    maps, so any stored line_map pointers should not be used.  */
 125 extern const struct line_map *linemap_add
 126   (struct line_maps *, enum lc_reason, unsigned int sysp,
 127    const char *to_file, unsigned int to_line);
 128
 129 /* Given a logical line, returns the map from which the corresponding
 130    (source file, line) pair can be deduced.  */
 131 extern const struct line_map *linemap_lookup
 132   (struct line_maps *, source_location);
 133
 134 /* Print the file names and line numbers of the #include commands
 135    which led to the map MAP, if any, to stderr.  Nothing is output if
 136    the most recently listed stack is the same as the current one.  */
 137 extern void linemap_print_containing_files (struct line_maps *,
 138                                             const struct line_map *);
 139
 140 /* Converts a map and a source_location to source line.  */
 141 #define SOURCE_LINE(MAP, LINE) \
 142   ((((LINE) - (MAP)->start_location) >> (MAP)->column_bits) + (MAP)->to_line)
 143
 144 #define SOURCE_COLUMN(MAP, LINE) \
 145   (((LINE) - (MAP)->start_location) & ((1 << (MAP)->column_bits) - 1))
 146
 147 /* Returns the last source line within a map.  This is the (last) line
 148    of the #include, or other directive, that caused a map change.  */
 149 #define LAST_SOURCE_LINE(MAP) \
 150   SOURCE_LINE (MAP, LAST_SOURCE_LINE_LOCATION (MAP))
 151 #define LAST_SOURCE_LINE_LOCATION(MAP) \
 152   ((((MAP)[1].start_location - 1 - (MAP)->start_location) \
 153     & ~((1 << (MAP)->column_bits) - 1))                   \
 154    + (MAP)->start_location)
 155
 156 /* Returns the map a given map was included from.  */
 157 #define INCLUDED_FROM(SET, MAP) (&(SET)->maps[(MAP)->included_from])
 158
 159 /* Nonzero if the map is at the bottom of the include stack.  */
 160 #define MAIN_FILE_P(MAP) ((MAP)->included_from < 0)
 161
 162 /* Set LOC to a source position that is the same line as the most recent
 163    linemap_line_start, but with the specified TO_COLUMN column number.  */
 164
 165 #define LINEMAP_POSITION_FOR_COLUMN(LOC, SET, TO_COLUMN) { \
 166   unsigned int to_column = (TO_COLUMN); \
 167   struct line_maps *set = (SET); \
 168   if (__builtin_expect (to_column >= set->max_column_hint, 0)) \
 169     (LOC) = linemap_position_for_column (set, to_column); \
 170   else { \
 171     source_location r = set->highest_line; \
 172     r = r + to_column; \
 173     if (r >= set->highest_location) \
 174       set->highest_location = r; \
 175     (LOC) = r;                   \
 176   }}
 177
 178
 179 extern source_location
 180 linemap_position_for_column (struct line_maps *set, unsigned int to_column);
 181 #endif /* !LIBCPP_LINE_MAP_H  */