src/location.c

   1 /* Locations for Bison
   2    Copyright (C) 2002, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
   3
   4    This file is part of Bison, the GNU Compiler Compiler.
   5
   6    This program is free software: you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation, either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #include <config.h>
  20 #include "system.h"
  21
  22 #include <mbswidth.h>
  23 #include <quotearg.h>
  24
  25 #include "complain.h"
  26 #include "location.h"
  27
  28 location const empty_location = EMPTY_LOCATION_INIT;
  29
  30 /* If BUF is null, add BUFSIZE (which in this case must be less than
  31    INT_MAX) to COLUMN; otherwise, add mbsnwidth (BUF, BUFSIZE, 0) to
  32    COLUMN.  If an overflow occurs, or might occur but is undetectable,
  33    return INT_MAX.  Assume COLUMN is nonnegative.  */
  34
  35 static inline int
  36 add_column_width (int column, char const *buf, size_t bufsize)
  37 {
  38   size_t width;
  39   unsigned int remaining_columns = INT_MAX - column;
  40
  41   if (buf)
  42     {
  43       if (INT_MAX / 2 <= bufsize)
  44         return INT_MAX;
  45       width = mbsnwidth (buf, bufsize, 0);
  46     }
  47   else
  48     width = bufsize;
  49
  50   return width <= remaining_columns ? column + width : INT_MAX;
  51 }
  52
  53 /* Set *LOC and adjust scanner cursor to account for token TOKEN of
  54    size SIZE.  */
  55
  56 void
  57 location_compute (location *loc, boundary *cur, char const *token, size_t size)
  58 {
  59   int line = cur->line;
  60   int column = cur->column;
  61   char const *p0 = token;
  62   char const *p = token;
  63   char const *lim = token + size;
  64
  65   loc->start = *cur;
  66
  67   for (p = token; p < lim; p++)
  68     switch (*p)
  69       {
  70       case '\n':
  71         line += line < INT_MAX;
  72         column = 1;
  73         p0 = p + 1;
  74         break;
  75
  76       case '\t':
  77         column = add_column_width (column, p0, p - p0);
  78         column = add_column_width (column, NULL, 8 - ((column - 1) & 7));
  79         p0 = p + 1;
  80         break;
  81
  82       default:
  83         break;
  84       }
  85
  86   cur->line = line;
  87   cur->column = column = add_column_width (column, p0, p - p0);
  88
  89   loc->end = *cur;
  90
  91   if (line == INT_MAX && loc->start.line != INT_MAX)
  92     warn_at (*loc, _("line number overflow"));
  93   if (column == INT_MAX && loc->start.column != INT_MAX)
  94     warn_at (*loc, _("column number overflow"));
  95 }
  96
  97
  98 /* Output to OUT the location LOC.
  99    Warning: it uses quotearg's slot 3.  */
 100 void
 101 location_print (FILE *out, location loc)
 102 {
 103   int end_col = 0 < loc.end.column ? loc.end.column - 1 : 0;
 104   fprintf (out, "%s:%d",
 105            quotearg_n_style (3, escape_quoting_style, loc.start.file),
 106            loc.start.line);
 107   if (0 <= loc.start.column)
 108     fprintf (out, ".%d", loc.start.column);
 109
 110   if (loc.start.file != loc.end.file)
 111     fprintf (out, "-%s:%d.%d",
 112              quotearg_n_style (3, escape_quoting_style, loc.end.file),
 113              loc.end.line, end_col);
 114   else if (loc.start.line < loc.end.line)
 115     fprintf (out, "-%d.%d", loc.end.line, end_col);
 116   else if (0 <= loc.start.column && loc.start.column < end_col)
 117     fprintf (out, "-%d", end_col);
 118 }
 119
 120 void
 121 boundary_set_from_string (boundary *bound, char *loc_str)
 122 {
 123   /* Must search in reverse since the file name field may
 124    * contain `.' or `:'.  */
 125   char *delim = strrchr (loc_str, '.');
 126   aver (delim);
 127   *delim = '\0';
 128   bound->column = atoi (delim+1);
 129   delim = strrchr (loc_str, ':');
 130   aver (delim);
 131   *delim = '\0';
 132   bound->line = atoi (delim+1);
 133   bound->file = uniqstr_new (loc_str);
 134 }