gdb/namespace.h

   1 /* Code dealing with "using" directives for GDB.
   2    Copyright (C) 2003-2023 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 NAMESPACE_H
  20 #define NAMESPACE_H
  21
  22 #include "gdbsupport/gdb_vecs.h"
  23 #include "gdbsupport/gdb_obstack.h"
  24
  25 /* This struct is designed to store data from using directives.  It
  26    says that names from namespace IMPORT_SRC should be visible within
  27    namespace IMPORT_DEST.  These form a linked list; NEXT is the next
  28    element of the list.  If the imported namespace or declaration has
  29    been aliased within the IMPORT_DEST namespace, ALIAS is set to a
  30    string representing the alias.  Otherwise, ALIAS is NULL.
  31    DECLARATION is the name of the imported declaration, if this import
  32    statement represents one.  Otherwise DECLARATION is NULL and this
  33    import statement represents a namespace.  DECL_LINE is the line
  34    where the using directive is written in the source code.
  35
  36    C++:      using namespace A;
  37    Fortran:  use A
  38    import_src = "A"
  39    import_dest = local scope of the import statement even such as ""
  40    alias = NULL
  41    declaration = NULL
  42    excludes = NULL
  43
  44    C++:      using A::x;
  45    Fortran:  use A, only: x
  46    import_src = "A"
  47    import_dest = local scope of the import statement even such as ""
  48    alias = NULL
  49    declaration = "x"
  50    excludes = NULL
  51    The declaration will get imported as import_dest::x.
  52
  53    C++ has no way to import all names except those listed ones.
  54    Fortran:  use A, localname => x
  55    import_src = "A"
  56    import_dest = local scope of the import statement even such as ""
  57    alias = "localname"
  58    declaration = "x"
  59    excludes = NULL
  60    +
  61    import_src = "A"
  62    import_dest = local scope of the import statement even such as ""
  63    alias = NULL
  64    declaration = NULL
  65    excludes = ["x"]
  66    All the entries of A get imported except of "x".  "x" gets imported as
  67    "localname".  "x" is not defined as a local name by this statement.
  68
  69    C++:      namespace LOCALNS = A;
  70    Fortran has no way to address non-local namespace/module.
  71    import_src = "A"
  72    import_dest = local scope of the import statement even such as ""
  73    alias = "LOCALNS"
  74    declaration = NULL
  75    excludes = NULL
  76    The namespace will get imported as the import_dest::LOCALNS
  77    namespace.
  78
  79    C++ cannot express it, it would be something like: using localname
  80    = A::x;
  81    Fortran:  use A, only localname => x
  82    import_src = "A"
  83    import_dest = local scope of the import statement even such as ""
  84    alias = "localname"
  85    declaration = "x"
  86    excludes = NULL
  87    The declaration will get imported as localname or
  88    `import_dest`localname.  */
  89
  90 struct using_direct
  91 {
  92   const char *import_src;
  93   const char *import_dest;
  94
  95   const char *alias;
  96   const char *declaration;
  97
  98   struct using_direct *next;
  99
 100   /* The line where the using directive was declared on the source file.
 101      This is used to check if the using directive is already active at the
 102      point where the inferior is stopped.  */
 103   unsigned int decl_line;
 104
 105   /* Used during import search to temporarily mark this node as
 106      searched.  */
 107   int searched;
 108
 109   /* USING_DIRECT has variable allocation size according to the number of
 110      EXCLUDES entries, the last entry is NULL.  */
 111   const char *excludes[1];
 112
 113   /* Returns true if the using_directive USING_DIR is valid in CURR_LINE.
 114      Because current GCC (at least version 12.2) sets the decl_line as
 115      the last line in the current block, we need to take this into
 116      consideration when checking the validity, by comparing it to
 117      BOUNDARY, the last line of the current block.  */
 118   bool valid_line (unsigned int boundary) const;
 119 };
 120
 121 extern void add_using_directive (struct using_direct **using_directives,
 122                                  const char *dest,
 123                                  const char *src,
 124                                  const char *alias,
 125                                  const char *declaration,
 126                                  const std::vector<const char *> &excludes,
 127                                  const unsigned int decl_line,
 128                                  int copy_names,
 129                                  struct obstack *obstack);
 130
 131 #endif /* NAMESPACE_H */