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