1  /* Remap file names for debug info for GNU assembler.
       2     Copyright (C) 2007-2023 Free Software Foundation, Inc.
       3  
       4     This file is part of GAS, the GNU Assembler.
       5  
       6     GAS 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, or (at your option)
       9     any later version.
      10  
      11     GAS 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 GAS; see the file COPYING.  If not, write to the Free
      18     Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
      19     02110-1301, USA.  */
      20  
      21  #include "as.h"
      22  #include "filenames.h"
      23  
      24  /* Structure recording the mapping from source file and directory
      25     names at compile time to those to be embedded in debug
      26     information.  */
      27  typedef struct debug_prefix_map
      28  {
      29    const char *old_prefix;
      30    const char *new_prefix;
      31    size_t old_len;
      32    size_t new_len;
      33    struct debug_prefix_map *next;
      34  } debug_prefix_map;
      35  
      36  /* Linked list of such structures.  */
      37  debug_prefix_map *debug_prefix_maps;
      38  
      39  
      40  /* Record a debug file prefix mapping.  ARG is the argument to
      41     -fdebug-prefix-map and must be of the form OLD=NEW.  */
      42  
      43  void
      44  add_debug_prefix_map (const char *arg)
      45  {
      46    debug_prefix_map *map;
      47    const char *p;
      48    char *o;
      49  
      50    p = strchr (arg, '=');
      51    if (!p)
      52      {
      53        as_fatal (_("invalid argument '%s' to -fdebug-prefix-map"), arg);
      54        return;
      55      }
      56    map = XNEW (debug_prefix_map);
      57    o = xstrdup (arg);
      58    map->old_prefix = o;
      59    map->old_len = p - arg;
      60    o[map->old_len] = 0;
      61    p++;
      62    map->new_prefix = xstrdup (p);
      63    map->new_len = strlen (p);
      64    map->next = debug_prefix_maps;
      65    debug_prefix_maps = map;
      66  }
      67  
      68  /* Perform user-specified mapping of debug filename prefixes.  Returns
      69     a newly allocated buffer containing the name corresponding to FILENAME.
      70     It is the caller's responsibility to free the buffer.  */
      71  
      72  char *
      73  remap_debug_filename (const char *filename)
      74  {
      75    debug_prefix_map *map;
      76  
      77    for (map = debug_prefix_maps; map; map = map->next)
      78      if (filename_ncmp (filename, map->old_prefix, map->old_len) == 0)
      79        {
      80  	const char *name = filename + map->old_len;
      81  	return concat (map->new_prefix, name, NULL);
      82        }
      83  	
      84    return xstrdup (filename);
      85  }