/* Remap file names for debug info for GNU assembler.
  Copyright (C) 2007-2024 Free Software Foundation, Inc.

  This file is part of GAS, the GNU Assembler.

  GAS 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.

  GAS 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 GAS; see the file COPYING.  If not, write to the Free
  Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
  02110-1301, USA.  */

#include "as.h"
#include "filenames.h"

/* Structure recording the mapping from source file and directory
  names at compile time to those to be embedded in debug
  information.  */
typedef struct debug_prefix_map
{
 const char *old_prefix;
 const char *new_prefix;
 size_t old_len;
 size_t new_len;
 struct debug_prefix_map *next;
} debug_prefix_map;

/* Linked list of such structures.  */
debug_prefix_map *debug_prefix_maps;


/* Record a debug file prefix mapping.  ARG is the argument to
  -fdebug-prefix-map and must be of the form OLD=NEW.  */

void
add_debug_prefix_map (const char *arg)
{
 debug_prefix_map *map;
 const char *p;
 char *o;

 p = strchr (arg, '=');
 if (!p)
   {
     as_fatal (_("invalid argument '%s' to -fdebug-prefix-map"), arg);
     return;
   }
 map = XNEW (debug_prefix_map);
 o = xstrdup (arg);
 map->old_prefix = o;
 map->old_len = p - arg;
 o[map->old_len] = 0;
 p++;
 map->new_prefix = xstrdup (p);
 map->new_len = strlen (p);
 map->next = debug_prefix_maps;
 debug_prefix_maps = map;
}

/* Perform user-specified mapping of debug filename prefixes.  Returns
  a newly allocated buffer containing the name corresponding to FILENAME.
  It is the caller's responsibility to free the buffer.  */

char *
remap_debug_filename (const char *filename)
{
 debug_prefix_map *map;

 for (map = debug_prefix_maps; map; map = map->next)
   if (filename_ncmp (filename, map->old_prefix, map->old_len) == 0)
     {
       const char *name = filename + map->old_len;
       return concat (map->new_prefix, name, NULL);
     }

 return xstrdup (filename);
}