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, Inc., 59 Temple Place - Suite 330,
  18 Boston, MA 02111-1307, USA.  */
  19
  20 /* Codes in a variable definition saying where the definition came from.
  21    Increasing numeric values signify less-overridable definitions.  */
  22 enum variable_origin
  23   {
  24     o_default,          /* Variable from the default set.  */
  25     o_env,              /* Variable from environment.  */
  26     o_file,             /* Variable given in a makefile.  */
  27     o_env_override,     /* Variable from environment, if -e.  */
  28     o_command,          /* Variable given by user.  */
  29     o_override,         /* Variable from an `override' directive.  */
  30     o_automatic,        /* Automatic variable -- cannot be set.  */
  31     o_invalid           /* Core dump time.  */
  32   };
  33
  34 /* Structure that represents one variable definition.
  35    Each bucket of the hash table is a chain of these,
  36    chained through `next'.  */
  37
  38 #define EXP_COUNT_BITS  15      /* This gets all the bitfields into 32 bits */
  39
  40 #define EXP_COUNT_MAX   ((1<<EXP_COUNT_BITS)-1)
  41
  42 struct variable
  43   {
  44     struct variable *next;      /* Link in the chain.  */
  45     char *name;                 /* Variable name.  */
  46     char *value;                /* Variable value.  */
  47     struct floc fileinfo;       /* Where the variable was defined.  */
  48     unsigned int recursive:1;   /* Gets recursively re-evaluated.  */
  49     unsigned int expanding:1;   /* Nonzero if currently being expanded.  */
  50     unsigned int exp_count:EXP_COUNT_BITS;
  51                                 /* If >1, allow this many self-referential
  52                                    expansions */
  53     unsigned int per_target:1;  /* Nonzero if a target-specific variable.  */
  54     unsigned int append:1;      /* Nonzero if an appending target-specific
  55                                    variable.  */
  56
  57     enum variable_origin
  58       origin ENUM_BITFIELD (3); /* Variable origin.  */
  59
  60     enum variable_export
  61       {
  62         v_export,               /* Export this variable.  */
  63         v_noexport,             /* Don't export this variable.  */
  64         v_ifset,                /* Export it if it has a non-default value.  */
  65         v_default               /* Decide in target_environment.  */
  66       } export ENUM_BITFIELD (2);
  67   };
  68
  69 /* Structure that represents a variable set.  */
  70
  71 struct variable_set
  72   {
  73     struct variable **table;    /* Hash table of variables.  */
  74     unsigned int buckets;       /* Number of hash buckets in `table'.  */
  75   };
  76
  77 /* Structure that represents a list of variable sets.  */
  78
  79 struct variable_set_list
  80   {
  81     struct variable_set_list *next;     /* Link in the chain.  */
  82     struct variable_set *set;           /* Variable set.  */
  83   };
  84
  85 extern char *variable_buffer;
  86 extern struct variable_set_list *current_variable_set_list;
  87
  88 /* expand.c */
  89 extern char *variable_buffer_output PARAMS ((char *ptr, char *string, unsigned int length));
  90 extern char *variable_expand PARAMS ((char *line));
  91 extern char *allocated_variable_expand_for_file PARAMS ((char *line, struct file *file));
  92 #define allocated_variable_expand(line) \
  93   allocated_variable_expand_for_file (line, (struct file *) 0)
  94 extern char *expand_argument PARAMS ((char *str, char *end));
  95 extern char *variable_expand_string PARAMS ((char *line, char *string,
  96                                              long length));
  97
  98 /* function.c */
  99 extern int handle_function PARAMS ((char **op, char **stringp));
 100 extern int pattern_matches PARAMS ((char *pattern, char *percent, char *str));
 101 extern char *subst_expand PARAMS ((char *o, char *text, char *subst, char *replace,
 102                 unsigned int slen, unsigned int rlen, int by_word, int suffix_only));
 103 extern char *patsubst_expand PARAMS ((char *o, char *text, char *pattern, char *replace,
 104                 char *pattern_percent, char *replace_percent));
 105
 106 /* expand.c */
 107 extern char *recursively_expand_for_file PARAMS ((struct variable *v,
 108                                                   struct file *file));
 109 #define recursively_expand(v)   recursively_expand_for_file (v, NULL)
 110
 111 /* variable.c */
 112 extern struct variable_set_list *create_new_variable_set PARAMS ((void));
 113 extern struct variable_set_list *push_new_variable_scope PARAMS ((void));
 114 extern void pop_variable_scope PARAMS ((void));
 115 extern void define_automatic_variables PARAMS ((void));
 116 extern void initialize_file_variables PARAMS ((struct file *file, int read));
 117 extern void print_file_variables PARAMS ((struct file *file));
 118 extern void print_variable_set PARAMS ((struct variable_set *set, char *prefix));
 119 extern void merge_variable_set_lists PARAMS ((struct variable_set_list **setlist0, struct variable_set_list *setlist1));
 120 extern struct variable *try_variable_definition PARAMS ((const struct floc *flocp, char *line, enum variable_origin origin, int target_var));
 121
 122 extern struct variable *lookup_variable PARAMS ((const char *name, unsigned int length));
 123 extern struct variable *lookup_variable_in_set PARAMS ((const char *name,
 124                                                         unsigned int length,
 125                                                         const struct variable_set *set));
 126
 127 extern struct variable *define_variable_in_set
 128     PARAMS ((char *name, unsigned int length, char *value,
 129              enum variable_origin origin, int recursive,
 130              struct variable_set *set, const struct floc *flocp));
 131
 132 /* Define a variable in the current variable set.  */
 133
 134 #define define_variable(n,l,v,o,r) \
 135           define_variable_in_set((n),(l),(v),(o),(r),\
 136                                  current_variable_set_list->set,NILF)
 137
 138 /* Define a variable with a location in the current variable set.  */
 139
 140 #define define_variable_loc(n,l,v,o,r,f) \
 141           define_variable_in_set((n),(l),(v),(o),(r),\
 142                                  current_variable_set_list->set,(f))
 143
 144 /* Define a variable in FILE's variable set.  */
 145
 146 #define define_variable_for_file(n,l,v,o,r,f) \
 147           define_variable_in_set((n),(l),(v),(o),(r),(f)->variables->set,NILF)
 148
 149 /* Warn that NAME is an undefined variable.  */
 150
 151 #define warn_undefined(n,l) do{\
 152                               if (warn_undefined_variables_flag) \
 153                                 error (reading_file, \
 154                                        _("warning: undefined variable `%.*s'"), \
 155                                 (int)(l), (n)); \
 156                               }while(0)
 157
 158 extern char **target_environment PARAMS ((struct file *file));
 159
 160 extern int export_all_variables;