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Diffstat (limited to 'libcpp/line-map.c')
| -rw-r--r-- | libcpp/line-map.c | 319 |
1 files changed, 319 insertions, 0 deletions
diff --git a/libcpp/line-map.c b/libcpp/line-map.c new file mode 100644 index 000000000..a82c4286f --- /dev/null +++ b/libcpp/line-map.c @@ -0,0 +1,319 @@ +/* Map logical line numbers to (source file, line number) pairs. + Copyright (C) 2001, 2003, 2004, 2007, 2008, 2009 + Free Software Foundation, Inc. + +This program 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. + +This program 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 this program; see the file COPYING3. If not see +<http://www.gnu.org/licenses/>. + + In other words, you are welcome to use, share and improve this program. + You are forbidden to forbid anyone else to use, share and improve + what you give them. Help stamp out software-hoarding! */ + +#include "config.h" +#include "system.h" +#include "line-map.h" + +static void trace_include (const struct line_maps *, const struct line_map *); + +/* Initialize a line map set. */ + +void +linemap_init (struct line_maps *set) +{ + set->maps = NULL; + set->allocated = 0; + set->used = 0; + set->last_listed = -1; + set->trace_includes = false; + set->depth = 0; + set->cache = 0; + set->highest_location = RESERVED_LOCATION_COUNT - 1; + set->highest_line = RESERVED_LOCATION_COUNT - 1; + set->max_column_hint = 0; + set->reallocator = 0; +} + +/* Check for and warn about line_maps entered but not exited. */ + +void +linemap_check_files_exited (struct line_maps *set) +{ + struct line_map *map; + /* Depending upon whether we are handling preprocessed input or + not, this can be a user error or an ICE. */ + for (map = &set->maps[set->used - 1]; ! MAIN_FILE_P (map); + map = INCLUDED_FROM (set, map)) + fprintf (stderr, "line-map.c: file \"%s\" entered but not left\n", + map->to_file); +} + +/* Free a line map set. */ + +void +linemap_free (struct line_maps *set) +{ + if (set->maps) + { + linemap_check_files_exited (set); + + free (set->maps); + } +} + +/* Add a mapping of logical source line to physical source file and + line number. + + The text pointed to by TO_FILE must have a lifetime + at least as long as the final call to lookup_line (). An empty + TO_FILE means standard input. If reason is LC_LEAVE, and + TO_FILE is NULL, then TO_FILE, TO_LINE and SYSP are given their + natural values considering the file we are returning to. + + FROM_LINE should be monotonic increasing across calls to this + function. A call to this function can relocate the previous set of + maps, so any stored line_map pointers should not be used. */ + +const struct line_map * +linemap_add (struct line_maps *set, enum lc_reason reason, + unsigned int sysp, const char *to_file, linenum_type to_line) +{ + struct line_map *map; + source_location start_location = set->highest_location + 1; + + if (set->used && start_location < set->maps[set->used - 1].start_location) + abort (); + + if (set->used == set->allocated) + { + line_map_realloc reallocator + = set->reallocator ? set->reallocator : xrealloc; + set->allocated = 2 * set->allocated + 256; + set->maps + = (struct line_map *) (*reallocator) (set->maps, + set->allocated + * sizeof (struct line_map)); + memset (&set->maps[set->used], 0, ((set->allocated - set->used) + * sizeof (struct line_map))); + } + + map = &set->maps[set->used]; + + if (to_file && *to_file == '\0' && reason != LC_RENAME_VERBATIM) + to_file = "<stdin>"; + + if (reason == LC_RENAME_VERBATIM) + reason = LC_RENAME; + + /* If we don't keep our line maps consistent, we can easily + segfault. Don't rely on the client to do it for us. */ + if (set->depth == 0) + reason = LC_ENTER; + else if (reason == LC_LEAVE) + { + struct line_map *from; + bool error; + + if (MAIN_FILE_P (map - 1)) + { + if (to_file == NULL) + { + set->depth--; + return NULL; + } + error = true; + reason = LC_RENAME; + from = map - 1; + } + else + { + from = INCLUDED_FROM (set, map - 1); + error = to_file && strcmp (from->to_file, to_file); + } + + /* Depending upon whether we are handling preprocessed input or + not, this can be a user error or an ICE. */ + if (error) + fprintf (stderr, "line-map.c: file \"%s\" left but not entered\n", + to_file); + + /* A TO_FILE of NULL is special - we use the natural values. */ + if (error || to_file == NULL) + { + to_file = from->to_file; + to_line = SOURCE_LINE (from, from[1].start_location); + sysp = from->sysp; + } + } + + map->reason = reason; + map->sysp = sysp; + map->start_location = start_location; + map->to_file = to_file; + map->to_line = to_line; + set->cache = set->used++; + map->column_bits = 0; + set->highest_location = start_location; + set->highest_line = start_location; + set->max_column_hint = 0; + + if (reason == LC_ENTER) + { + map->included_from = set->depth == 0 ? -1 : (int) (set->used - 2); + set->depth++; + if (set->trace_includes) + trace_include (set, map); + } + else if (reason == LC_RENAME) + map->included_from = map[-1].included_from; + else if (reason == LC_LEAVE) + { + set->depth--; + map->included_from = INCLUDED_FROM (set, map - 1)->included_from; + } + + return map; +} + +source_location +linemap_line_start (struct line_maps *set, linenum_type to_line, + unsigned int max_column_hint) +{ + struct line_map *map = &set->maps[set->used - 1]; + source_location highest = set->highest_location; + source_location r; + linenum_type last_line = SOURCE_LINE (map, set->highest_line); + int line_delta = to_line - last_line; + bool add_map = false; + if (line_delta < 0 + || (line_delta > 10 && line_delta * map->column_bits > 1000) + || (max_column_hint >= (1U << map->column_bits)) + || (max_column_hint <= 80 && map->column_bits >= 10)) + { + add_map = true; + } + else + max_column_hint = set->max_column_hint; + if (add_map) + { + int column_bits; + if (max_column_hint > 100000 || highest > 0xC0000000) + { + /* If the column number is ridiculous or we've allocated a huge + number of source_locations, give up on column numbers. */ + max_column_hint = 0; + if (highest >0xF0000000) + return 0; + column_bits = 0; + } + else + { + column_bits = 7; + while (max_column_hint >= (1U << column_bits)) + column_bits++; + max_column_hint = 1U << column_bits; + } + /* Allocate the new line_map. However, if the current map only has a + single line we can sometimes just increase its column_bits instead. */ + if (line_delta < 0 + || last_line != map->to_line + || SOURCE_COLUMN (map, highest) >= (1U << column_bits)) + map = (struct line_map *) linemap_add (set, LC_RENAME, map->sysp, + map->to_file, to_line); + map->column_bits = column_bits; + r = map->start_location + ((to_line - map->to_line) << column_bits); + } + else + r = highest - SOURCE_COLUMN (map, highest) + + (line_delta << map->column_bits); + set->highest_line = r; + if (r > set->highest_location) + set->highest_location = r; + set->max_column_hint = max_column_hint; + return r; +} + +source_location +linemap_position_for_column (struct line_maps *set, unsigned int to_column) +{ + source_location r = set->highest_line; + if (to_column >= set->max_column_hint) + { + if (r >= 0xC000000 || to_column > 100000) + { + /* Running low on source_locations - disable column numbers. */ + return r; + } + else + { + struct line_map *map = &set->maps[set->used - 1]; + r = linemap_line_start (set, SOURCE_LINE (map, r), to_column + 50); + } + } + r = r + to_column; + if (r >= set->highest_location) + set->highest_location = r; + return r; +} + +/* Given a logical line, returns the map from which the corresponding + (source file, line) pair can be deduced. Since the set is built + chronologically, the logical lines are monotonic increasing, and so + the list is sorted and we can use a binary search. */ + +const struct line_map * +linemap_lookup (struct line_maps *set, source_location line) +{ + unsigned int md, mn, mx; + const struct line_map *cached; + + mn = set->cache; + mx = set->used; + + cached = &set->maps[mn]; + /* We should get a segfault if no line_maps have been added yet. */ + if (line >= cached->start_location) + { + if (mn + 1 == mx || line < cached[1].start_location) + return cached; + } + else + { + mx = mn; + mn = 0; + } + + while (mx - mn > 1) + { + md = (mn + mx) / 2; + if (set->maps[md].start_location > line) + mx = md; + else + mn = md; + } + + set->cache = mn; + return &set->maps[mn]; +} + +/* Print an include trace, for e.g. the -H option of the preprocessor. */ + +static void +trace_include (const struct line_maps *set, const struct line_map *map) +{ + unsigned int i = set->depth; + + while (--i) + putc ('.', stderr); + fprintf (stderr, " %s\n", map->to_file); +} |