variable.h

   1 /* Definitions for using variables in GNU Make.
   2 Copyright (C) 1988, 1989, 1990, 1991, 1992 Free Software Foundation, Inc.
   3 This file is part of GNU Make.
   4
   5 GNU Make is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation; either version 2, or (at your option)
   8 any later version.
   9
  10 GNU Make is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with GNU Make; see the file COPYING.  If not, write to
  17 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  18
  19 /* Codes in a variable definition saying where the definition came from.
  20    Increasing numeric values signify less-overridable definitions.  */
  21 enum variable_origin
  22   {
  23     o_default,          /* Variable from the default set.  */
  24     o_env,              /* Variable from environment.  */
  25     o_file,             /* Variable given in a makefile.  */
  26     o_env_override,     /* Variable from environment, if -e.  */
  27     o_command,          /* Variable given by user.  */
  28     o_override,         /* Variable from an `override' directive.  */
  29     o_automatic,        /* Automatic variable -- cannot be set.  */
  30     o_invalid           /* Core dump time.  */
  31   };
  32
  33 /* Structure that represents one variable definition.
  34    Each bucket of the hash table is a chain of these,
  35    chained through `next'.  */
  36
  37 struct variable
  38   {
  39     struct variable *next;      /* Link in the chain.  */
  40     char *name;                 /* Variable name.  */
  41     char *value;                /* Variable value.  */
  42     enum variable_origin
  43       origin ENUM_BITFIELD (3); /* Variable origin.  */
  44     unsigned int recursive:1;   /* Gets recursively re-evaluated.  */
  45     unsigned int expanding:1;   /* Nonzero if currently being expanded.  */
  46     enum
  47       {
  48         v_export,               /* Export this variable.  */
  49         v_noexport,             /* Don't export this variable.  */
  50         v_ifset,                /* Export it if it has a non-default value.  */
  51         v_default               /* Decide in target_environment.  */
  52       } export ENUM_BITFIELD (2);
  53   };
  54
  55 /* Structure that represents a variable set.  */
  56
  57 struct variable_set
  58   {
  59     struct variable **table;    /* Hash table of variables.  */
  60     unsigned int buckets;       /* Number of hash buckets in `table'.  */
  61   };
  62
  63 /* Structure that represents a list of variable sets.  */
  64
  65 struct variable_set_list
  66   {
  67     struct variable_set_list *next;     /* Link in the chain.  */
  68     struct variable_set *set;           /* Variable set.  */
  69   };
  70
  71 extern struct variable_set_list *current_variable_set_list;
  72
  73
  74 extern void push_new_variable_scope (), pop_variable_scope ();
  75
  76 extern int handle_function ();
  77
  78 extern char *variable_buffer_output ();
  79 extern char *variable_expand (), *variable_expand_for_file ();
  80 extern char *allocated_variable_expand_for_file ();
  81 #define allocated_variable_expand(line) \
  82   allocated_variable_expand_for_file (line, (struct file *) 0)
  83 extern char *expand_argument ();
  84
  85 extern void define_automatic_variables ();
  86 extern void initialize_file_variables ();
  87 extern void print_file_variables ();
  88
  89 extern void merge_variable_set_lists ();
  90
  91 extern struct variable *try_variable_definition ();
  92
  93 extern struct variable *lookup_variable (), *define_variable ();
  94 extern struct variable *define_variable_for_file ();
  95
  96 extern int pattern_matches ();
  97 extern char *subst_expand (), *patsubst_expand (), *recursively_expand ();
  98
  99 extern char **target_environment ();
 100 extern int export_all_variables;