subst.h

   1 /* subst.h -- Names of externally visible functions in subst.c. */
   2
   3 /* Copyright (C) 1993-2017 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
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation, either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    Bash is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with Bash.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #if !defined (_SUBST_H_)
  22 #define _SUBST_H_
  23
  24 #include "stdc.h"
  25
  26 /* Constants which specify how to handle backslashes and quoting in
  27    expand_word_internal ().  Q_DOUBLE_QUOTES means to use the function
  28    slashify_in_quotes () to decide whether the backslash should be
  29    retained.  Q_HERE_DOCUMENT means slashify_in_here_document () to
  30    decide whether to retain the backslash.  Q_KEEP_BACKSLASH means
  31    to unconditionally retain the backslash.  Q_PATQUOTE means that we're
  32    expanding a pattern ${var%#[#%]pattern} in an expansion surrounded
  33    by double quotes. Q_DOLBRACE means we are expanding a ${...} word, so
  34    backslashes should also escape { and } and be removed. */
  35 #define Q_DOUBLE_QUOTES  0x001
  36 #define Q_HERE_DOCUMENT  0x002
  37 #define Q_KEEP_BACKSLASH 0x004
  38 #define Q_PATQUOTE       0x008
  39 #define Q_QUOTED         0x010
  40 #define Q_ADDEDQUOTES    0x020
  41 #define Q_QUOTEDNULL     0x040
  42 #define Q_DOLBRACE       0x080
  43 #define Q_ARITH          0x100  /* expanding string for arithmetic evaluation */
  44 #define Q_ARRAYSUB       0x200  /* expanding indexed array subscript */
  45
  46 /* Flag values controlling how assignment statements are treated. */
  47 #define ASS_APPEND      0x0001
  48 #define ASS_MKLOCAL     0x0002
  49 #define ASS_MKASSOC     0x0004
  50 #define ASS_MKGLOBAL    0x0008  /* force global assignment */
  51 #define ASS_NAMEREF     0x0010  /* assigning to nameref variable */
  52 #define ASS_FORCE       0x0020  /* force assignment even to readonly variable */
  53 #define ASS_CHKLOCAL    0x0040  /* check local variable before assignment */
  54 #define ASS_NOEXPAND    0x0080  /* don't expand associative array subscripts */
  55 #define ASS_NOEVAL      0x0100  /* don't evaluate value as expression */
  56 #define ASS_NOLONGJMP   0x0200  /* don't longjmp on fatal assignment error */
  57
  58 /* Flags for the string extraction functions. */
  59 #define SX_NOALLOC      0x0001  /* just skip; don't return substring */
  60 #define SX_VARNAME      0x0002  /* variable name; for string_extract () */
  61 #define SX_REQMATCH     0x0004  /* closing/matching delimiter required */
  62 #define SX_COMMAND      0x0008  /* extracting a shell script/command */
  63 #define SX_NOCTLESC     0x0010  /* don't honor CTLESC quoting */
  64 #define SX_NOESCCTLNUL  0x0020  /* don't let CTLESC quote CTLNUL */
  65 #define SX_NOLONGJMP    0x0040  /* don't longjmp on fatal error */
  66 #define SX_ARITHSUB     0x0080  /* extracting $(( ... )) (currently unused) */
  67 #define SX_POSIXEXP     0x0100  /* extracting new Posix pattern removal expansions in extract_dollar_brace_string */
  68 #define SX_WORD         0x0200  /* extracting word in ${param op word} */
  69 #define SX_COMPLETE     0x0400  /* extracting word for completion */
  70 #define SX_STRIPDQ      0x0800  /* strip double quotes when extracting double-quoted string */
  71
  72 /* Remove backslashes which are quoting backquotes from STRING.  Modifies
  73    STRING, and returns a pointer to it. */
  74 extern char * de_backslash __P((char *));
  75
  76 /* Replace instances of \! in a string with !. */
  77 extern void unquote_bang __P((char *));
  78
  79 /* Extract the $( construct in STRING, and return a new string.
  80    Start extracting at (SINDEX) as if we had just seen "$(".
  81    Make (SINDEX) get the position just after the matching ")".
  82    XFLAGS is additional flags to pass to other extraction functions, */
  83 extern char *extract_command_subst __P((char *, int *, int));
  84
  85 /* Extract the $[ construct in STRING, and return a new string.
  86    Start extracting at (SINDEX) as if we had just seen "$[".
  87    Make (SINDEX) get the position just after the matching "]". */
  88 extern char *extract_arithmetic_subst __P((char *, int *));
  89
  90 #if defined (PROCESS_SUBSTITUTION)
  91 /* Extract the <( or >( construct in STRING, and return a new string.
  92    Start extracting at (SINDEX) as if we had just seen "<(".
  93    Make (SINDEX) get the position just after the matching ")". */
  94 extern char *extract_process_subst __P((char *, char *, int *, int));
  95 #endif /* PROCESS_SUBSTITUTION */
  96
  97 /* Extract the name of the variable to bind to from the assignment string. */
  98 extern char *assignment_name __P((char *));
  99
 100 /* Return a single string of all the words present in LIST, separating
 101    each word with SEP. */
 102 extern char *string_list_internal __P((WORD_LIST *, char *));
 103
 104 /* Return a single string of all the words present in LIST, separating
 105    each word with a space. */
 106 extern char *string_list __P((WORD_LIST *));
 107
 108 /* Turn $* into a single string, obeying POSIX rules. */
 109 extern char *string_list_dollar_star __P((WORD_LIST *, int, int));
 110
 111 /* Expand $@ into a single string, obeying POSIX rules. */
 112 extern char *string_list_dollar_at __P((WORD_LIST *, int, int));
 113
 114 /* Turn the positional paramters into a string, understanding quoting and
 115    the various subtleties of using the first character of $IFS as the
 116    separator.  Calls string_list_dollar_at, string_list_dollar_star, and
 117    string_list as appropriate. */
 118 extern char *string_list_pos_params __P((int, WORD_LIST *, int));
 119
 120 /* Perform quoted null character removal on each element of LIST.
 121    This modifies LIST. */
 122 extern void word_list_remove_quoted_nulls __P((WORD_LIST *));
 123
 124 /* This performs word splitting and quoted null character removal on
 125    STRING. */
 126 extern WORD_LIST *list_string __P((char *, char *, int));
 127
 128 extern char *ifs_firstchar  __P((int *));
 129 extern char *get_word_from_string __P((char **, char *, char **));
 130 extern char *strip_trailing_ifs_whitespace __P((char *, char *, int));
 131
 132 /* Given STRING, an assignment string, get the value of the right side
 133    of the `=', and bind it to the left side.  If EXPAND is true, then
 134    perform tilde expansion, parameter expansion, command substitution,
 135    and arithmetic expansion on the right-hand side.  Do not perform word
 136    splitting on the result of expansion. */
 137 extern int do_assignment __P((char *));
 138 extern int do_assignment_no_expand __P((char *));
 139 extern int do_word_assignment __P((WORD_DESC *, int));
 140
 141 /* Append SOURCE to TARGET at INDEX.  SIZE is the current amount
 142    of space allocated to TARGET.  SOURCE can be NULL, in which
 143    case nothing happens.  Gets rid of SOURCE by free ()ing it.
 144    Returns TARGET in case the location has changed. */
 145 extern char *sub_append_string __P((char *, char *, int *, size_t *));
 146
 147 /* Append the textual representation of NUMBER to TARGET.
 148    INDEX and SIZE are as in SUB_APPEND_STRING. */
 149 extern char *sub_append_number __P((intmax_t, char *, int *, int *));
 150
 151 /* Return the word list that corresponds to `$*'. */
 152 extern WORD_LIST *list_rest_of_args __P((void));
 153
 154 /* Make a single large string out of the dollar digit variables,
 155    and the rest_of_args.  If DOLLAR_STAR is 1, then obey the special
 156    case of "$*" with respect to IFS. */
 157 extern char *string_rest_of_args __P((int));
 158
 159 extern int number_of_args __P((void));
 160
 161 /* Expand STRING by performing parameter expansion, command substitution,
 162    and arithmetic expansion.  Dequote the resulting WORD_LIST before
 163    returning it, but do not perform word splitting.  The call to
 164    remove_quoted_nulls () is made here because word splitting normally
 165    takes care of quote removal. */
 166 extern WORD_LIST *expand_string_unsplit __P((char *, int));
 167
 168 /* Expand the rhs of an assignment statement. */
 169 extern WORD_LIST *expand_string_assignment __P((char *, int));
 170
 171 /* Expand a prompt string. */
 172 extern WORD_LIST *expand_prompt_string __P((char *, int, int));
 173
 174 /* Expand STRING just as if you were expanding a word.  This also returns
 175    a list of words.  Note that filename globbing is *NOT* done for word
 176    or string expansion, just when the shell is expanding a command.  This
 177    does parameter expansion, command substitution, arithmetic expansion,
 178    and word splitting.  Dequote the resultant WORD_LIST before returning. */
 179 extern WORD_LIST *expand_string __P((char *, int));
 180
 181 /* Convenience functions that expand strings to strings, taking care of
 182    converting the WORD_LIST * returned by the expand_string* functions
 183    to a string and deallocating the WORD_LIST *. */
 184 extern char *expand_string_to_string __P((char *, int));
 185 extern char *expand_string_unsplit_to_string __P((char *, int));
 186 extern char *expand_assignment_string_to_string __P((char *, int));
 187
 188 /* Expand an arithmetic expression string */
 189 extern char *expand_arith_string __P((char *, int));
 190
 191 /* De-quote quoted characters in STRING. */
 192 extern char *dequote_string __P((char *));
 193
 194 /* De-quote CTLESC-escaped CTLESC or CTLNUL characters in STRING. */
 195 extern char *dequote_escapes __P((const char *));
 196
 197 extern WORD_DESC *dequote_word __P((WORD_DESC *));
 198
 199 /* De-quote quoted characters in each word in LIST. */
 200 extern WORD_LIST *dequote_list __P((WORD_LIST *));
 201
 202 /* Expand WORD, performing word splitting on the result.  This does
 203    parameter expansion, command substitution, arithmetic expansion,
 204    word splitting, and quote removal. */
 205 extern WORD_LIST *expand_word __P((WORD_DESC *, int));
 206
 207 /* Expand WORD, but do not perform word splitting on the result.  This
 208    does parameter expansion, command substitution, arithmetic expansion,
 209    and quote removal. */
 210 extern WORD_LIST *expand_word_unsplit __P((WORD_DESC *, int));
 211 extern WORD_LIST *expand_word_leave_quoted __P((WORD_DESC *, int));
 212
 213 /* Return the value of a positional parameter.  This handles values > 10. */
 214 extern char *get_dollar_var_value __P((intmax_t));
 215
 216 /* Quote a string to protect it from word splitting. */
 217 extern char *quote_string __P((char *));
 218
 219 /* Quote escape characters (characters special to interals of expansion)
 220    in a string. */
 221 extern char *quote_escapes __P((const char *));
 222
 223 /* And remove such quoted special characters. */
 224 extern char *remove_quoted_escapes __P((char *));
 225
 226 /* Remove CTLNUL characters from STRING unless they are quoted with CTLESC. */
 227 extern char *remove_quoted_nulls __P((char *));
 228
 229 /* Perform quote removal on STRING.  If QUOTED > 0, assume we are obeying the
 230    backslash quoting rules for within double quotes. */
 231 extern char *string_quote_removal __P((char *, int));
 232
 233 /* Perform quote removal on word WORD.  This allocates and returns a new
 234    WORD_DESC *. */
 235 extern WORD_DESC *word_quote_removal __P((WORD_DESC *, int));
 236
 237 /* Perform quote removal on all words in LIST.  If QUOTED is non-zero,
 238    the members of the list are treated as if they are surrounded by
 239    double quotes.  Return a new list, or NULL if LIST is NULL. */
 240 extern WORD_LIST *word_list_quote_removal __P((WORD_LIST *, int));
 241
 242 /* Called when IFS is changed to maintain some private variables. */
 243 extern void setifs __P((SHELL_VAR *));
 244
 245 /* Return the value of $IFS, or " \t\n" if IFS is unset. */
 246 extern char *getifs __P((void));
 247
 248 /* This splits a single word into a WORD LIST on $IFS, but only if the word
 249    is not quoted.  list_string () performs quote removal for us, even if we
 250    don't do any splitting. */
 251 extern WORD_LIST *word_split __P((WORD_DESC *, char *));
 252
 253 /* Take the list of words in LIST and do the various substitutions.  Return
 254    a new list of words which is the expanded list, and without things like
 255    variable assignments. */
 256 extern WORD_LIST *expand_words __P((WORD_LIST *));
 257
 258 /* Same as expand_words (), but doesn't hack variable or environment
 259    variables. */
 260 extern WORD_LIST *expand_words_no_vars __P((WORD_LIST *));
 261
 262 /* Perform the `normal shell expansions' on a WORD_LIST.  These are
 263    brace expansion, tilde expansion, parameter and variable substitution,
 264    command substitution, arithmetic expansion, and word splitting. */
 265 extern WORD_LIST *expand_words_shellexp __P((WORD_LIST *));
 266
 267 extern WORD_DESC *command_substitute __P((char *, int, int));
 268 extern char *pat_subst __P((char *, char *, char *, int));
 269
 270 #if defined (PROCESS_SUBSTITUTION)
 271 extern int fifos_pending __P((void));
 272 extern int num_fifos __P((void));
 273 extern void unlink_fifo_list __P((void));
 274 extern void unlink_fifo __P((int));
 275
 276 extern char *copy_fifo_list __P((int *));
 277 extern void unlink_new_fifos __P((char *, int));
 278 extern void close_new_fifos __P((char *, int));
 279
 280 extern void clear_fifo_list __P((void));
 281
 282 extern int find_procsub_child __P((pid_t));
 283 extern void set_procsub_status __P((int, pid_t, int));
 284
 285 extern void wait_procsubs __P((void));
 286 extern void reap_procsubs __P((void));
 287 #endif
 288
 289 extern WORD_LIST *list_string_with_quotes __P((char *));
 290
 291 #if defined (ARRAY_VARS)
 292 extern char *extract_array_assignment_list __P((char *, int *));
 293 #endif
 294
 295 #if defined (COND_COMMAND)
 296 extern char *remove_backslashes __P((char *));
 297 extern char *cond_expand_word __P((WORD_DESC *, int));
 298 #endif
 299
 300 /* Flags for skip_to_delim */
 301 #define SD_NOJMP        0x001   /* don't longjmp on fatal error. */
 302 #define SD_INVERT       0x002   /* look for chars NOT in passed set */
 303 #define SD_NOQUOTEDELIM 0x004   /* don't let single or double quotes act as delimiters */
 304 #define SD_NOSKIPCMD    0x008   /* don't skip over $(, <(, or >( command/process substitution; parse them as commands */
 305 #define SD_EXTGLOB      0x010   /* skip over extended globbing patterns if appropriate */
 306 #define SD_IGNOREQUOTE  0x020   /* single and double quotes are not special */
 307 #define SD_GLOB         0x040   /* skip over glob patterns like bracket expressions */
 308 #define SD_NOPROCSUB    0x080   /* don't parse process substitutions as commands */
 309 #define SD_COMPLETE     0x100   /* skip_to_delim during completion */
 310 #define SD_HISTEXP      0x200   /* skip_to_delim during history expansion */
 311 #define SD_ARITHEXP     0x400   /* skip_to_delim during arithmetic expansion */
 312
 313 extern int skip_to_delim __P((char *, int, char *, int));
 314
 315 #if defined (BANG_HISTORY)
 316 extern int skip_to_histexp __P((char *, int, char *, int));
 317 #endif
 318
 319 #if defined (READLINE)
 320 extern int char_is_quoted __P((char *, int));
 321 extern int unclosed_pair __P((char *, int, char *));
 322 extern WORD_LIST *split_at_delims __P((char *, int, char *, int, int, int *, int *));
 323 #endif
 324
 325 /* Variables used to keep track of the characters in IFS. */
 326 extern SHELL_VAR *ifs_var;
 327 extern char *ifs_value;
 328 extern unsigned char ifs_cmap[];
 329 extern int ifs_is_set, ifs_is_null;
 330
 331 #if defined (HANDLE_MULTIBYTE)
 332 extern unsigned char ifs_firstc[];
 333 extern size_t ifs_firstc_len;
 334 #else
 335 extern unsigned char ifs_firstc;
 336 #endif
 337
 338 extern int assigning_in_environment;
 339 extern int expanding_redir;
 340 extern int inherit_errexit;
 341
 342 extern pid_t last_command_subst_pid;
 343
 344 /* Evaluates to 1 if C is a character in $IFS. */
 345 #define isifs(c)        (ifs_cmap[(unsigned char)(c)] != 0)
 346
 347 /* How to determine the quoted state of the character C. */
 348 #define QUOTED_CHAR(c)  ((c) == CTLESC)
 349
 350 /* Is the first character of STRING a quoted NULL character? */
 351 #define QUOTED_NULL(string) ((string)[0] == CTLNUL && (string)[1] == '\0')
 352
 353 extern void invalidate_cached_quoted_dollar_at __P((void));
 354
 355 #endif /* !_SUBST_H_ */