variable.h

   1 /* Definitions for using variables in GNU Make.
   2 Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
   3 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software
   4 Foundation, Inc.
   5 This file is part of GNU Make.
   6
   7 GNU Make is free software; you can redistribute it and/or modify it under the
   8 terms of the GNU General Public License as published by the Free Software
   9 Foundation; either version 2, or (at your option) any later version.
  10
  11 GNU Make is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  13 A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License along with
  16 GNU Make; see the file COPYING.  If not, write to the Free Software
  17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.  */
  18
  19 #include "hash.h"
  20
  21 /* Codes in a variable definition saying where the definition came from.
  22    Increasing numeric values signify less-overridable definitions.  */
  23 enum variable_origin
  24   {
  25     o_default,          /* Variable from the default set.  */
  26     o_env,              /* Variable from environment.  */
  27     o_file,             /* Variable given in a makefile.  */
  28     o_env_override,     /* Variable from environment, if -e.  */
  29     o_command,          /* Variable given by user.  */
  30     o_override,         /* Variable from an `override' directive.  */
  31     o_automatic,        /* Automatic variable -- cannot be set.  */
  32     o_invalid           /* Core dump time.  */
  33   };
  34
  35 enum variable_flavor
  36   {
  37     f_bogus,            /* Bogus (error) */
  38     f_simple,           /* Simple definition (:=) */
  39     f_recursive,        /* Recursive definition (=) */
  40     f_append,           /* Appending definition (+=) */
  41     f_conditional       /* Conditional definition (?=) */
  42   };
  43
  44 /* Structure that represents one variable definition.
  45    Each bucket of the hash table is a chain of these,
  46    chained through `next'.  */
  47
  48 #define EXP_COUNT_BITS  15      /* This gets all the bitfields into 32 bits */
  49 #define EXP_COUNT_MAX   ((1<<EXP_COUNT_BITS)-1)
  50
  51 struct variable
  52   {
  53     char *name;                 /* Variable name.  */
  54     int length;                 /* strlen (name) */
  55     char *value;                /* Variable value.  */
  56     struct floc fileinfo;       /* Where the variable was defined.  */
  57     unsigned int recursive:1;   /* Gets recursively re-evaluated.  */
  58     unsigned int append:1;      /* Nonzero if an appending target-specific
  59                                    variable.  */
  60     unsigned int conditional:1; /* Nonzero if set with a ?=. */
  61     unsigned int per_target:1;  /* Nonzero if a target-specific variable.  */
  62     unsigned int special:1;     /* Nonzero if this is a special variable. */
  63     unsigned int exportable:1;  /* Nonzero if the variable _could_ be
  64                                    exported.  */
  65     unsigned int expanding:1;   /* Nonzero if currently being expanded.  */
  66     unsigned int exp_count:EXP_COUNT_BITS;
  67                                 /* If >1, allow this many self-referential
  68                                    expansions.  */
  69     enum variable_flavor
  70       flavor ENUM_BITFIELD (3); /* Variable flavor.  */
  71     enum variable_origin
  72       origin ENUM_BITFIELD (3); /* Variable origin.  */
  73     enum variable_export
  74       {
  75         v_export,               /* Export this variable.  */
  76         v_noexport,             /* Don't export this variable.  */
  77         v_ifset,                /* Export it if it has a non-default value.  */
  78         v_default               /* Decide in target_environment.  */
  79       } export ENUM_BITFIELD (2);
  80   };
  81
  82 /* Structure that represents a variable set.  */
  83
  84 struct variable_set
  85   {
  86     struct hash_table table;    /* Hash table of variables.  */
  87   };
  88
  89 /* Structure that represents a list of variable sets.  */
  90
  91 struct variable_set_list
  92   {
  93     struct variable_set_list *next;     /* Link in the chain.  */
  94     struct variable_set *set;           /* Variable set.  */
  95   };
  96
  97 /* Structure used for pattern-specific variables.  */
  98
  99 struct pattern_var
 100   {
 101     struct pattern_var *next;
 102     const char *suffix;
 103     const char *target;
 104     unsigned int len;
 105     struct variable variable;
 106   };
 107
 108 extern char *variable_buffer;
 109 extern struct variable_set_list *current_variable_set_list;
 110
 111 /* expand.c */
 112 char *variable_buffer_output (char *ptr, const char *string, unsigned int length);
 113 char *variable_expand (const char *line);
 114 char *variable_expand_for_file (const char *line, struct file *file);
 115 char *allocated_variable_expand_for_file (const char *line, struct file *file);
 116 #define allocated_variable_expand(line) \
 117   allocated_variable_expand_for_file (line, (struct file *) 0)
 118 char *expand_argument (const char *str, const char *end);
 119 char *variable_expand_string (char *line, const char *string, long length);
 120 void install_variable_buffer (char **bufp, unsigned int *lenp);
 121 void restore_variable_buffer (char *buf, unsigned int len);
 122
 123 /* function.c */
 124 int handle_function (char **op, const char **stringp);
 125 int pattern_matches (const char *pattern, const char *percent, const char *str);
 126 char *subst_expand (char *o, const char *text, const char *subst,
 127                     const char *replace, unsigned int slen, unsigned int rlen,
 128                     int by_word);
 129 char *patsubst_expand_pat (char *o, const char *text, const char *pattern,
 130                            const char *replace, const char *pattern_percent,
 131                            const char *replace_percent);
 132 char *patsubst_expand (char *o, const char *text, char *pattern, char *replace);
 133
 134 /* expand.c */
 135 char *recursively_expand_for_file (struct variable *v, struct file *file);
 136 #define recursively_expand(v)   recursively_expand_for_file (v, NULL)
 137
 138 /* variable.c */
 139 struct variable_set_list *create_new_variable_set (void);
 140 void free_variable_set (struct variable_set_list *);
 141 struct variable_set_list *push_new_variable_scope (void);
 142 void pop_variable_scope (void);
 143 void define_automatic_variables (void);
 144 void initialize_file_variables (struct file *file, int reading);
 145 void print_file_variables (const struct file *file);
 146 void print_variable_set (struct variable_set *set, char *prefix);
 147 void merge_variable_set_lists (struct variable_set_list **to_list,
 148                                struct variable_set_list *from_list);
 149 struct variable *do_variable_definition (const struct floc *flocp,
 150                                          const char *name, const char *value,
 151                                          enum variable_origin origin,
 152                                          enum variable_flavor flavor,
 153                                          int target_var);
 154 struct variable *parse_variable_definition (struct variable *v, char *line);
 155 struct variable *try_variable_definition (const struct floc *flocp, char *line,
 156                                           enum variable_origin origin,
 157                                           int target_var);
 158 void init_hash_global_variable_set (void);
 159 void hash_init_function_table (void);
 160 struct variable *lookup_variable (const char *name, unsigned int length);
 161 struct variable *lookup_variable_in_set (const char *name, unsigned int length,
 162                                          const struct variable_set *set);
 163
 164 struct variable *define_variable_in_set (const char *name, unsigned int length,
 165                                          const char *value,
 166                                          enum variable_origin origin,
 167                                          int recursive,
 168                                          struct variable_set *set,
 169                                          const struct floc *flocp);
 170
 171 /* Define a variable in the current variable set.  */
 172
 173 #define define_variable(n,l,v,o,r) \
 174           define_variable_in_set((n),(l),(v),(o),(r),\
 175                                  current_variable_set_list->set,NILF)
 176
 177 /* Define a variable with a location in the current variable set.  */
 178
 179 #define define_variable_loc(n,l,v,o,r,f) \
 180           define_variable_in_set((n),(l),(v),(o),(r),\
 181                                  current_variable_set_list->set,(f))
 182
 183 /* Define a variable with a location in the global variable set.  */
 184
 185 #define define_variable_global(n,l,v,o,r,f) \
 186           define_variable_in_set((n),(l),(v),(o),(r),NULL,(f))
 187
 188 /* Define a variable in FILE's variable set.  */
 189
 190 #define define_variable_for_file(n,l,v,o,r,f) \
 191           define_variable_in_set((n),(l),(v),(o),(r),(f)->variables->set,NILF)
 192
 193 /* Warn that NAME is an undefined variable.  */
 194
 195 #define warn_undefined(n,l) do{\
 196                               if (warn_undefined_variables_flag) \
 197                                 error (reading_file, \
 198                                        _("warning: undefined variable `%.*s'"), \
 199                                 (int)(l), (n)); \
 200                               }while(0)
 201
 202 char **target_environment (struct file *file);
 203
 204 struct pattern_var *create_pattern_var (const char *target,
 205                                         const char *suffix);
 206
 207 extern int export_all_variables;
 208
 209 #define MAKELEVEL_NAME "MAKELEVEL"
 210 #define MAKELEVEL_LENGTH (sizeof (MAKELEVEL_NAME) - 1)