gdb/namespace.h

   1 /* Code dealing with "using" directives for GDB.
   2    Copyright (C) 2003-2024 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   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 #ifndef GDB_NAMESPACE_H
  20 #define GDB_NAMESPACE_H
  21
  22 #include "gdbsupport/gdb_obstack.h"
  23
  24 /* This struct is designed to store data from using directives.  It
  25    says that names from namespace IMPORT_SRC should be visible within
  26    namespace IMPORT_DEST.  These form a linked list; NEXT is the next
  27    element of the list.  If the imported namespace or declaration has
  28    been aliased within the IMPORT_DEST namespace, ALIAS is set to a
  29    string representing the alias.  Otherwise, ALIAS is NULL.
  30    DECLARATION is the name of the imported declaration, if this import
  31    statement represents one.  Otherwise DECLARATION is NULL and this
  32    import statement represents a namespace.  DECL_LINE is the line
  33    where the using directive is written in the source code.
  34
  35    C++:      using namespace A;
  36    Fortran:  use A
  37    import_src = "A"
  38    import_dest = local scope of the import statement even such as ""
  39    alias = NULL
  40    declaration = NULL
  41    excludes = NULL
  42
  43    C++:      using A::x;
  44    Fortran:  use A, only: x
  45    import_src = "A"
  46    import_dest = local scope of the import statement even such as ""
  47    alias = NULL
  48    declaration = "x"
  49    excludes = NULL
  50    The declaration will get imported as import_dest::x.
  51
  52    C++ has no way to import all names except those listed ones.
  53    Fortran:  use A, localname => x
  54    import_src = "A"
  55    import_dest = local scope of the import statement even such as ""
  56    alias = "localname"
  57    declaration = "x"
  58    excludes = NULL
  59    +
  60    import_src = "A"
  61    import_dest = local scope of the import statement even such as ""
  62    alias = NULL
  63    declaration = NULL
  64    excludes = ["x"]
  65    All the entries of A get imported except of "x".  "x" gets imported as
  66    "localname".  "x" is not defined as a local name by this statement.
  67
  68    C++:      namespace LOCALNS = A;
  69    Fortran has no way to address non-local namespace/module.
  70    import_src = "A"
  71    import_dest = local scope of the import statement even such as ""
  72    alias = "LOCALNS"
  73    declaration = NULL
  74    excludes = NULL
  75    The namespace will get imported as the import_dest::LOCALNS
  76    namespace.
  77
  78    C++ cannot express it, it would be something like: using localname
  79    = A::x;
  80    Fortran:  use A, only localname => x
  81    import_src = "A"
  82    import_dest = local scope of the import statement even such as ""
  83    alias = "localname"
  84    declaration = "x"
  85    excludes = NULL
  86    The declaration will get imported as localname or
  87    `import_dest`localname.  */
  88
  89 struct using_direct
  90 {
  91   const char *import_src;
  92   const char *import_dest;
  93
  94   const char *alias;
  95   const char *declaration;
  96
  97   struct using_direct *next;
  98
  99   /* The line where the using directive was declared on the source file.
 100      This is used to check if the using directive is already active at the
 101      point where the inferior is stopped.  */
 102   unsigned int decl_line;
 103
 104   /* Used during import search to temporarily mark this node as
 105      searched.  */
 106   int searched;
 107
 108   /* USING_DIRECT has variable allocation size according to the number of
 109      EXCLUDES entries, the last entry is NULL.  */
 110   const char *excludes[1];
 111
 112   /* Returns true if the using_directive USING_DIR is valid in CURR_LINE.
 113      Because current GCC (at least version 12.2) sets the decl_line as
 114      the last line in the current block, we need to take this into
 115      consideration when checking the validity, by comparing it to
 116      BOUNDARY, the last line of the current block.  */
 117   bool valid_line (unsigned int boundary) const;
 118 };
 119
 120 extern void add_using_directive (struct using_direct **using_directives,
 121                                  const char *dest,
 122                                  const char *src,
 123                                  const char *alias,
 124                                  const char *declaration,
 125                                  const std::vector<const char *> &excludes,
 126                                  const unsigned int decl_line,
 127                                  struct obstack *obstack);
 128
 129 #endif /* GDB_NAMESPACE_H */