variables.h

   1 /* variables.h -- data structures for shell variables. */
   2
   3 /* Copyright (C) 1987-2005 Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bash, the Bourne Again SHell.
   6
   7    Bash is free software; you can redistribute it and/or modify it
   8    under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2, or (at your option)
  10    any later version.
  11
  12    Bash is distributed in the hope that it will be useful, but WITHOUT
  13    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  14    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  15    License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with Bash; see the file COPYING.  If not, write to the Free
  19    Software Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */
  20
  21 #if !defined (_VARIABLES_H_)
  22 #define _VARIABLES_H_
  23
  24 #include "stdc.h"
  25 #include "array.h"
  26
  27 /* Shell variables and functions are stored in hash tables. */
  28 #include "hashlib.h"
  29
  30 #include "conftypes.h"
  31
  32 /* A variable context. */
  33 typedef struct var_context {
  34   char *name;           /* empty or NULL means global context */
  35   int scope;            /* 0 means global context */
  36   int flags;
  37   struct var_context *up;       /* previous function calls */
  38   struct var_context *down;     /* down towards global context */
  39   HASH_TABLE *table;            /* variables at this scope */
  40 } VAR_CONTEXT;
  41
  42 /* Flags for var_context->flags */
  43 #define VC_HASLOCAL     0x01
  44 #define VC_HASTMPVAR    0x02
  45 #define VC_FUNCENV      0x04    /* also function if name != NULL */
  46 #define VC_BLTNENV      0x08    /* builtin_env */
  47 #define VC_TEMPENV      0x10    /* temporary_env */
  48
  49 #define VC_TEMPFLAGS    (VC_FUNCENV|VC_BLTNENV|VC_TEMPENV)
  50
  51 /* Accessing macros */
  52 #define vc_isfuncenv(vc)        (((vc)->flags & VC_FUNCENV) != 0)
  53 #define vc_isbltnenv(vc)        (((vc)->flags & VC_BLTNENV) != 0)
  54 #define vc_istempenv(vc)        (((vc)->flags & (VC_TEMPFLAGS)) == VC_TEMPENV)
  55
  56 #define vc_istempscope(vc)      (((vc)->flags & (VC_TEMPENV|VC_BLTNENV)) != 0)
  57
  58 #define vc_haslocals(vc)        (((vc)->flags & VC_HASLOCAL) != 0)
  59 #define vc_hastmpvars(vc)       (((vc)->flags & VC_HASTMPVAR) != 0)
  60
  61 /* What a shell variable looks like. */
  62
  63 typedef struct variable *sh_var_value_func_t __P((struct variable *));
  64 typedef struct variable *sh_var_assign_func_t __P((struct variable *, char *, arrayind_t));
  65
  66 /* For the future */
  67 union _value {
  68   char *s;                      /* string value */
  69   intmax_t i;                   /* int value */
  70   COMMAND *f;                   /* function */
  71   ARRAY *a;                     /* array */
  72   HASH_TABLE *h;                /* associative array */
  73   double d;                     /* floating point number */
  74 #if defined (HAVE_LONG_DOUBLE)
  75   long double ld;               /* long double */
  76 #endif
  77   struct variable *v;           /* possible indirect variable use */
  78   void *opaque;                 /* opaque data for future use */
  79 };
  80
  81 typedef struct variable {
  82   char *name;                   /* Symbol that the user types. */
  83   char *value;                  /* Value that is returned. */
  84   char *exportstr;              /* String for the environment. */
  85   sh_var_value_func_t *dynamic_value;   /* Function called to return a `dynamic'
  86                                    value for a variable, like $SECONDS
  87                                    or $RANDOM. */
  88   sh_var_assign_func_t *assign_func; /* Function called when this `special
  89                                    variable' is assigned a value in
  90                                    bind_variable. */
  91   int attributes;               /* export, readonly, array, invisible... */
  92   int context;                  /* Which context this variable belongs to. */
  93 } SHELL_VAR;
  94
  95 typedef struct _vlist {
  96   SHELL_VAR **list;
  97   int list_size;        /* allocated size */
  98   int list_len;         /* current number of entries */
  99 } VARLIST;
 100
 101 /* The various attributes that a given variable can have. */
 102 /* First, the user-visible attributes */
 103 #define att_exported    0x0000001       /* export to environment */
 104 #define att_readonly    0x0000002       /* cannot change */
 105 #define att_array       0x0000004       /* value is an array */
 106 #define att_function    0x0000008       /* value is a function */
 107 #define att_integer     0x0000010       /* internal representation is int */
 108 #define att_local       0x0000020       /* variable is local to a function */
 109 #define att_assoc       0x0000040       /* variable is an associative array */
 110 #define att_trace       0x0000080       /* function is traced with DEBUG trap */
 111
 112 #define attmask_user    0x0000fff
 113
 114 /* Internal attributes used for bookkeeping */
 115 #define att_invisible   0x0001000       /* cannot see */
 116 #define att_nounset     0x0002000       /* cannot unset */
 117 #define att_noassign    0x0004000       /* assignment not allowed */
 118 #define att_imported    0x0008000       /* came from environment */
 119 #define att_special     0x0010000       /* requires special handling */
 120
 121 #define attmask_int     0x00ff000
 122
 123 /* Internal attributes used for variable scoping. */
 124 #define att_tempvar     0x0100000       /* variable came from the temp environment */
 125 #define att_propagate   0x0200000       /* propagate to previous scope */
 126
 127 #define attmask_scope   0x0f00000
 128
 129 #define exported_p(var)         ((((var)->attributes) & (att_exported)))
 130 #define readonly_p(var)         ((((var)->attributes) & (att_readonly)))
 131 #define array_p(var)            ((((var)->attributes) & (att_array)))
 132 #define function_p(var)         ((((var)->attributes) & (att_function)))
 133 #define integer_p(var)          ((((var)->attributes) & (att_integer)))
 134 #define local_p(var)            ((((var)->attributes) & (att_local)))
 135 #define assoc_p(var)            ((((var)->attributes) & (att_assoc)))
 136 #define trace_p(var)            ((((var)->attributes) & (att_trace)))
 137
 138 #define invisible_p(var)        ((((var)->attributes) & (att_invisible)))
 139 #define non_unsettable_p(var)   ((((var)->attributes) & (att_nounset)))
 140 #define noassign_p(var)         ((((var)->attributes) & (att_noassign)))
 141 #define imported_p(var)         ((((var)->attributes) & (att_imported)))
 142 #define specialvar_p(var)       ((((var)->attributes) & (att_special)))
 143
 144 #define tempvar_p(var)          ((((var)->attributes) & (att_tempvar)))
 145
 146 /* Acessing variable values: rvalues */
 147 #define value_cell(var)         ((var)->value)
 148 #define function_cell(var)      (COMMAND *)((var)->value)
 149 #define array_cell(var)         (ARRAY *)((var)->value)
 150
 151 #define var_isnull(var)         ((var)->value == 0)
 152 #define var_isset(var)          ((var)->value != 0)
 153
 154 /* Assigning variable values: lvalues */
 155 #define var_setvalue(var, str)  ((var)->value = (str))
 156 #define var_setfunc(var, func)  ((var)->value = (char *)(func))
 157 #define var_setarray(var, arr)  ((var)->value = (char *)(arr))
 158
 159 /* Make VAR be auto-exported. */
 160 #define set_auto_export(var) \
 161   do { (var)->attributes |= att_exported; array_needs_making = 1; } while (0)
 162
 163 #define SETVARATTR(var, attr, undo) \
 164         ((undo == 0) ? ((var)->attributes |= (attr)) \
 165                      : ((var)->attributes &= ~(attr)))
 166
 167 #define VSETATTR(var, attr)     ((var)->attributes |= (attr))
 168 #define VUNSETATTR(var, attr)   ((var)->attributes &= ~(attr))
 169
 170 #define VGETFLAGS(var)          ((var)->attributes)
 171
 172 #define VSETFLAGS(var, flags)   ((var)->attributes = (flags))
 173 #define VCLRFLAGS(var)          ((var)->attributes = 0)
 174
 175 /* Macros to perform various operations on `exportstr' member of a SHELL_VAR. */
 176 #define CLEAR_EXPORTSTR(var)    (var)->exportstr = (char *)NULL
 177 #define COPY_EXPORTSTR(var)     ((var)->exportstr) ? savestring ((var)->exportstr) : (char *)NULL
 178 #define SET_EXPORTSTR(var, value)  (var)->exportstr = (value)
 179 #define SAVE_EXPORTSTR(var, value) (var)->exportstr = (value) ? savestring (value) : (char *)NULL
 180
 181 #define FREE_EXPORTSTR(var) \
 182         do { if ((var)->exportstr) free ((var)->exportstr); } while (0)
 183
 184 #define CACHE_IMPORTSTR(var, value) \
 185         (var)->exportstr = savestring (value)
 186
 187 #define INVALIDATE_EXPORTSTR(var) \
 188         do { \
 189           if ((var)->exportstr) \
 190             { \
 191               free ((var)->exportstr); \
 192               (var)->exportstr = (char *)NULL; \
 193             } \
 194         } while (0)
 195
 196 /* Stuff for hacking variables. */
 197 typedef int sh_var_map_func_t __P((SHELL_VAR *));
 198
 199 /* Where we keep the variables and functions */
 200 extern VAR_CONTEXT *global_variables;
 201 extern VAR_CONTEXT *shell_variables;
 202
 203 extern HASH_TABLE *shell_functions;
 204 extern HASH_TABLE *temporary_env;
 205
 206 extern int variable_context;
 207 extern char *dollar_vars[];
 208 extern char **export_env;
 209
 210 extern void initialize_shell_variables __P((char **, int));
 211 extern SHELL_VAR *set_if_not __P((char *, char *));
 212
 213 extern void sh_set_lines_and_columns __P((int, int));
 214 extern void set_pwd __P((void));
 215 extern void set_ppid __P((void));
 216 extern void make_funcname_visible __P((int));
 217
 218 extern SHELL_VAR *var_lookup __P((const char *, VAR_CONTEXT *));
 219
 220 extern SHELL_VAR *find_function __P((const char *));
 221 extern FUNCTION_DEF *find_function_def __P((const char *));
 222 extern SHELL_VAR *find_variable __P((const char *));
 223 extern SHELL_VAR *find_variable_internal __P((const char *, int));
 224 extern SHELL_VAR *find_tempenv_variable __P((const char *));
 225 extern SHELL_VAR *copy_variable __P((SHELL_VAR *));
 226 extern SHELL_VAR *make_local_variable __P((const char *));
 227 extern SHELL_VAR *bind_variable __P((const char *, char *, int));
 228 extern SHELL_VAR *bind_function __P((const char *, COMMAND *));
 229
 230 extern void bind_function_def __P((const char *, FUNCTION_DEF *));
 231
 232 extern SHELL_VAR **map_over __P((sh_var_map_func_t *, VAR_CONTEXT *));
 233 SHELL_VAR **map_over_funcs __P((sh_var_map_func_t *));
 234
 235 extern SHELL_VAR **all_shell_variables __P((void));
 236 extern SHELL_VAR **all_shell_functions __P((void));
 237 extern SHELL_VAR **all_visible_variables __P((void));
 238 extern SHELL_VAR **all_visible_functions __P((void));
 239 extern SHELL_VAR **all_exported_variables __P((void));
 240 extern SHELL_VAR **local_exported_variables __P((void));
 241 extern SHELL_VAR **all_local_variables __P((void));
 242 #if defined (ARRAY_VARS)
 243 extern SHELL_VAR **all_array_variables __P((void));
 244 #endif
 245 extern char **all_variables_matching_prefix __P((const char *));
 246
 247 extern char **make_var_array __P((HASH_TABLE *));
 248 extern char **add_or_supercede_exported_var __P((char *, int));
 249
 250 extern char *get_variable_value __P((SHELL_VAR *));
 251 extern char *get_string_value __P((const char *));
 252 extern char *sh_get_env_value __P((const char *));
 253 extern char *make_variable_value __P((SHELL_VAR *, char *, int));
 254
 255 extern SHELL_VAR *bind_variable_value __P((SHELL_VAR *, char *, int));
 256 extern SHELL_VAR *bind_int_variable __P((char *, char *));
 257 extern SHELL_VAR *bind_var_to_int __P((char *, intmax_t));
 258
 259 extern int assign_in_env __P((WORD_DESC *));
 260
 261 extern int unbind_variable __P((const char *));
 262 extern int unbind_func __P((const char *));
 263 extern int unbind_function_def __P((const char *));
 264 extern int makunbound __P((const char *, VAR_CONTEXT *));
 265 extern int kill_local_variable __P((const char *));
 266 extern void delete_all_variables __P((HASH_TABLE *));
 267 extern void delete_all_contexts __P((VAR_CONTEXT *));
 268
 269 extern VAR_CONTEXT *new_var_context __P((char *, int));
 270 extern void dispose_var_context __P((VAR_CONTEXT *));
 271 extern VAR_CONTEXT *push_var_context __P((char *, int, HASH_TABLE *));
 272 extern void pop_var_context __P((void));
 273 extern VAR_CONTEXT *push_scope __P((int, HASH_TABLE *));
 274 extern void pop_scope __P((int));
 275
 276 extern void push_context __P((char *, int, HASH_TABLE *));
 277 extern void pop_context __P((void));
 278 extern void push_dollar_vars __P((void));
 279 extern void pop_dollar_vars __P((void));
 280 extern void dispose_saved_dollar_vars __P((void));
 281
 282 extern void push_args __P((WORD_LIST *));
 283 extern void pop_args __P((void));
 284
 285 extern void adjust_shell_level __P((int));
 286 extern void non_unsettable __P((char *));
 287 extern void dispose_variable __P((SHELL_VAR *));
 288 extern void dispose_used_env_vars __P((void));
 289 extern void dispose_function_env __P((void));
 290 extern void dispose_builtin_env __P((void));
 291 extern void merge_temporary_env __P((void));
 292 extern void merge_builtin_env __P((void));
 293 extern void kill_all_local_variables __P((void));
 294
 295 extern void set_var_read_only __P((char *));
 296 extern void set_func_read_only __P((const char *));
 297 extern void set_var_auto_export __P((char *));
 298 extern void set_func_auto_export __P((const char *));
 299
 300 extern void sort_variables __P((SHELL_VAR **));
 301
 302 extern void maybe_make_export_env __P((void));
 303 extern void update_export_env_inplace __P((char *, int, char *));
 304 extern void put_command_name_into_env __P((char *));
 305 extern void put_gnu_argv_flags_into_env __P((intmax_t, char *));
 306
 307 extern void print_var_list __P((SHELL_VAR **));
 308 extern void print_func_list __P((SHELL_VAR **));
 309 extern void print_assignment __P((SHELL_VAR *));
 310 extern void print_var_value __P((SHELL_VAR *, int));
 311 extern void print_var_function __P((SHELL_VAR *));
 312
 313 #if defined (ARRAY_VARS)
 314 extern SHELL_VAR *make_new_array_variable __P((char *));
 315 extern SHELL_VAR *make_local_array_variable __P((char *));
 316
 317 extern void set_pipestatus_array __P((int *, int));
 318 #endif
 319
 320 extern void set_pipestatus_from_exit __P((int));
 321
 322 /* The variable in NAME has just had its state changed.  Check to see if it
 323    is one of the special ones where something special happens. */
 324 extern void stupidly_hack_special_variables __P((char *));
 325
 326 extern int get_random_number __P((void));
 327
 328 /* The `special variable' functions that get called when a particular
 329    variable is set. */
 330 extern void sv_ifs __P((char *));
 331 extern void sv_path __P((char *));
 332 extern void sv_mail __P((char *));
 333 extern void sv_globignore __P((char *));
 334 extern void sv_ignoreeof __P((char *));
 335 extern void sv_strict_posix __P((char *));
 336 extern void sv_optind __P((char *));
 337 extern void sv_opterr __P((char *));
 338 extern void sv_locale __P((char *));
 339
 340 #if defined (READLINE)
 341 extern void sv_comp_wordbreaks __P((char *));
 342 extern void sv_terminal __P((char *));
 343 extern void sv_hostfile __P((char *));
 344 extern void sv_winsize __P((char *));
 345 #endif
 346
 347 #if defined (__CYGWIN__)
 348 extern void sv_home __P((char *));
 349 #endif
 350
 351 #if defined (HISTORY)
 352 extern void sv_histsize __P((char *));
 353 extern void sv_histignore __P((char *));
 354 extern void sv_history_control __P((char *));
 355 #  if defined (BANG_HISTORY)
 356 extern void sv_histchars __P((char *));
 357 #  endif
 358 extern void sv_histtimefmt __P((char *));
 359 #endif /* HISTORY */
 360
 361 #if defined (HAVE_TZSET) && defined (PROMPT_STRING_DECODE)
 362 extern void sv_tz __P((char *));
 363 #endif
 364
 365 #endif /* !_VARIABLES_H_ */