subst.h

   1 /* subst.h -- Names of externally visible functions in subst.c. */
   2
   3 /* Copyright (C) 1993-2010 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  0x01
  36 #define Q_HERE_DOCUMENT  0x02
  37 #define Q_KEEP_BACKSLASH 0x04
  38 #define Q_PATQUOTE       0x08
  39 #define Q_QUOTED         0x10
  40 #define Q_ADDEDQUOTES    0x20
  41 #define Q_QUOTEDNULL     0x40
  42 #define Q_DOLBRACE       0x80
  43
  44 /* Flag values controlling how assignment statements are treated. */
  45 #define ASS_APPEND      0x0001
  46 #define ASS_MKLOCAL     0x0002
  47 #define ASS_MKASSOC     0x0004
  48 #define ASS_MKGLOBAL    0x0008  /* force global assignment */
  49 #define ASS_NAMEREF     0x0010  /* assigning to nameref variable */
  50 #define ASS_FROMREF     0x0020  /* assigning from value of nameref variable */
  51
  52 /* Flags for the string extraction functions. */
  53 #define SX_NOALLOC      0x0001  /* just skip; don't return substring */
  54 #define SX_VARNAME      0x0002  /* variable name; for string_extract () */
  55 #define SX_REQMATCH     0x0004  /* closing/matching delimiter required */
  56 #define SX_COMMAND      0x0008  /* extracting a shell script/command */
  57 #define SX_NOCTLESC     0x0010  /* don't honor CTLESC quoting */
  58 #define SX_NOESCCTLNUL  0x0020  /* don't let CTLESC quote CTLNUL */
  59 #define SX_NOLONGJMP    0x0040  /* don't longjmp on fatal error */
  60 #define SX_ARITHSUB     0x0080  /* extracting $(( ... )) (currently unused) */
  61 #define SX_POSIXEXP     0x0100  /* extracting new Posix pattern removal expansions in extract_dollar_brace_string */
  62 #define SX_WORD         0x0200  /* extracting word in ${param op word} */
  63
  64 /* Remove backslashes which are quoting backquotes from STRING.  Modifies
  65    STRING, and returns a pointer to it. */
  66 extern char * de_backslash __P((char *));
  67
  68 /* Replace instances of \! in a string with !. */
  69 extern void unquote_bang __P((char *));
  70
  71 /* Extract the $( construct in STRING, and return a new string.
  72    Start extracting at (SINDEX) as if we had just seen "$(".
  73    Make (SINDEX) get the position just after the matching ")".
  74    XFLAGS is additional flags to pass to other extraction functions, */
  75 extern char *extract_command_subst __P((char *, int *, int));
  76
  77 /* Extract the $[ construct in STRING, and return a new string.
  78    Start extracting at (SINDEX) as if we had just seen "$[".
  79    Make (SINDEX) get the position just after the matching "]". */
  80 extern char *extract_arithmetic_subst __P((char *, int *));
  81
  82 #if defined (PROCESS_SUBSTITUTION)
  83 /* Extract the <( or >( construct in STRING, and return a new string.
  84    Start extracting at (SINDEX) as if we had just seen "<(".
  85    Make (SINDEX) get the position just after the matching ")". */
  86 extern char *extract_process_subst __P((char *, char *, int *, int));
  87 #endif /* PROCESS_SUBSTITUTION */
  88
  89 /* Extract the name of the variable to bind to from the assignment string. */
  90 extern char *assignment_name __P((char *));
  91
  92 /* Return a single string of all the words present in LIST, separating
  93    each word with SEP. */
  94 extern char *string_list_internal __P((WORD_LIST *, char *));
  95
  96 /* Return a single string of all the words present in LIST, separating
  97    each word with a space. */
  98 extern char *string_list __P((WORD_LIST *));
  99
 100 /* Turn $* into a single string, obeying POSIX rules. */
 101 extern char *string_list_dollar_star __P((WORD_LIST *));
 102
 103 /* Expand $@ into a single string, obeying POSIX rules. */
 104 extern char *string_list_dollar_at __P((WORD_LIST *, int));
 105
 106 /* Turn the positional paramters into a string, understanding quoting and
 107    the various subtleties of using the first character of $IFS as the
 108    separator.  Calls string_list_dollar_at, string_list_dollar_star, and
 109    string_list as appropriate. */
 110 extern char *string_list_pos_params __P((int, WORD_LIST *, int));
 111
 112 /* Perform quoted null character removal on each element of LIST.
 113    This modifies LIST. */
 114 extern void word_list_remove_quoted_nulls __P((WORD_LIST *));
 115
 116 /* This performs word splitting and quoted null character removal on
 117    STRING. */
 118 extern WORD_LIST *list_string __P((char *, char *, int));
 119
 120 extern char *ifs_firstchar  __P((int *));
 121 extern char *get_word_from_string __P((char **, char *, char **));
 122 extern char *strip_trailing_ifs_whitespace __P((char *, char *, int));
 123
 124 /* Given STRING, an assignment string, get the value of the right side
 125    of the `=', and bind it to the left side.  If EXPAND is true, then
 126    perform tilde expansion, parameter expansion, command substitution,
 127    and arithmetic expansion on the right-hand side.  Do not perform word
 128    splitting on the result of expansion. */
 129 extern int do_assignment __P((char *));
 130 extern int do_assignment_no_expand __P((char *));
 131 extern int do_word_assignment __P((WORD_DESC *, int));
 132
 133 /* Append SOURCE to TARGET at INDEX.  SIZE is the current amount
 134    of space allocated to TARGET.  SOURCE can be NULL, in which
 135    case nothing happens.  Gets rid of SOURCE by free ()ing it.
 136    Returns TARGET in case the location has changed. */
 137 extern char *sub_append_string __P((char *, char *, int *, int *));
 138
 139 /* Append the textual representation of NUMBER to TARGET.
 140    INDEX and SIZE are as in SUB_APPEND_STRING. */
 141 extern char *sub_append_number __P((intmax_t, char *, int *, int *));
 142
 143 /* Return the word list that corresponds to `$*'. */
 144 extern WORD_LIST *list_rest_of_args __P((void));
 145
 146 /* Make a single large string out of the dollar digit variables,
 147    and the rest_of_args.  If DOLLAR_STAR is 1, then obey the special
 148    case of "$*" with respect to IFS. */
 149 extern char *string_rest_of_args __P((int));
 150
 151 extern int number_of_args __P((void));
 152
 153 /* Expand STRING by performing parameter expansion, command substitution,
 154    and arithmetic expansion.  Dequote the resulting WORD_LIST before
 155    returning it, but do not perform word splitting.  The call to
 156    remove_quoted_nulls () is made here because word splitting normally
 157    takes care of quote removal. */
 158 extern WORD_LIST *expand_string_unsplit __P((char *, int));
 159
 160 /* Expand the rhs of an assignment statement. */
 161 extern WORD_LIST *expand_string_assignment __P((char *, int));
 162
 163 /* Expand a prompt string. */
 164 extern WORD_LIST *expand_prompt_string __P((char *, int, int));
 165
 166 /* Expand STRING just as if you were expanding a word.  This also returns
 167    a list of words.  Note that filename globbing is *NOT* done for word
 168    or string expansion, just when the shell is expanding a command.  This
 169    does parameter expansion, command substitution, arithmetic expansion,
 170    and word splitting.  Dequote the resultant WORD_LIST before returning. */
 171 extern WORD_LIST *expand_string __P((char *, int));
 172
 173 /* Convenience functions that expand strings to strings, taking care of
 174    converting the WORD_LIST * returned by the expand_string* functions
 175    to a string and deallocating the WORD_LIST *. */
 176 extern char *expand_string_to_string __P((char *, int));
 177 extern char *expand_string_unsplit_to_string __P((char *, int));
 178 extern char *expand_assignment_string_to_string __P((char *, int));
 179
 180 /* Expand an arithmetic expression string */
 181 extern char *expand_arith_string __P((char *, int));
 182
 183 /* De-quote quoted characters in STRING. */
 184 extern char *dequote_string __P((char *));
 185
 186 /* De-quote CTLESC-escaped CTLESC or CTLNUL characters in STRING. */
 187 extern char *dequote_escapes __P((char *));
 188
 189 /* De-quote quoted characters in each word in LIST. */
 190 extern WORD_LIST *dequote_list __P((WORD_LIST *));
 191
 192 /* Expand WORD, performing word splitting on the result.  This does
 193    parameter expansion, command substitution, arithmetic expansion,
 194    word splitting, and quote removal. */
 195 extern WORD_LIST *expand_word __P((WORD_DESC *, int));
 196
 197 /* Expand WORD, but do not perform word splitting on the result.  This
 198    does parameter expansion, command substitution, arithmetic expansion,
 199    and quote removal. */
 200 extern WORD_LIST *expand_word_unsplit __P((WORD_DESC *, int));
 201 extern WORD_LIST *expand_word_leave_quoted __P((WORD_DESC *, int));
 202
 203 /* Return the value of a positional parameter.  This handles values > 10. */
 204 extern char *get_dollar_var_value __P((intmax_t));
 205
 206 /* Quote a string to protect it from word splitting. */
 207 extern char *quote_string __P((char *));
 208
 209 /* Quote escape characters (characters special to interals of expansion)
 210    in a string. */
 211 extern char *quote_escapes __P((char *));
 212
 213 /* And remove such quoted special characters. */
 214 extern char *remove_quoted_escapes __P((char *));
 215
 216 /* Remove CTLNUL characters from STRING unless they are quoted with CTLESC. */
 217 extern char *remove_quoted_nulls __P((char *));
 218
 219 /* Perform quote removal on STRING.  If QUOTED > 0, assume we are obeying the
 220    backslash quoting rules for within double quotes. */
 221 extern char *string_quote_removal __P((char *, int));
 222
 223 /* Perform quote removal on word WORD.  This allocates and returns a new
 224    WORD_DESC *. */
 225 extern WORD_DESC *word_quote_removal __P((WORD_DESC *, int));
 226
 227 /* Perform quote removal on all words in LIST.  If QUOTED is non-zero,
 228    the members of the list are treated as if they are surrounded by
 229    double quotes.  Return a new list, or NULL if LIST is NULL. */
 230 extern WORD_LIST *word_list_quote_removal __P((WORD_LIST *, int));
 231
 232 /* Called when IFS is changed to maintain some private variables. */
 233 extern void setifs __P((SHELL_VAR *));
 234
 235 /* Return the value of $IFS, or " \t\n" if IFS is unset. */
 236 extern char *getifs __P((void));
 237
 238 /* This splits a single word into a WORD LIST on $IFS, but only if the word
 239    is not quoted.  list_string () performs quote removal for us, even if we
 240    don't do any splitting. */
 241 extern WORD_LIST *word_split __P((WORD_DESC *, char *));
 242
 243 /* Take the list of words in LIST and do the various substitutions.  Return
 244    a new list of words which is the expanded list, and without things like
 245    variable assignments. */
 246 extern WORD_LIST *expand_words __P((WORD_LIST *));
 247
 248 /* Same as expand_words (), but doesn't hack variable or environment
 249    variables. */
 250 extern WORD_LIST *expand_words_no_vars __P((WORD_LIST *));
 251
 252 /* Perform the `normal shell expansions' on a WORD_LIST.  These are
 253    brace expansion, tilde expansion, parameter and variable substitution,
 254    command substitution, arithmetic expansion, and word splitting. */
 255 extern WORD_LIST *expand_words_shellexp __P((WORD_LIST *));
 256
 257 extern WORD_DESC *command_substitute __P((char *, int));
 258 extern char *pat_subst __P((char *, char *, char *, int));
 259
 260 extern int fifos_pending __P((void));
 261 extern int num_fifos __P((void));
 262 extern void unlink_fifo_list __P((void));
 263 extern void unlink_fifo __P((int));
 264
 265 extern char *copy_fifo_list __P((int *));
 266 extern void unlink_new_fifos __P((char *, int));
 267 extern void close_new_fifos __P((char *, int));
 268
 269 extern WORD_LIST *list_string_with_quotes __P((char *));
 270
 271 #if defined (ARRAY_VARS)
 272 extern char *extract_array_assignment_list __P((char *, int *));
 273 #endif
 274
 275 #if defined (COND_COMMAND)
 276 extern char *remove_backslashes __P((char *));
 277 extern char *cond_expand_word __P((WORD_DESC *, int));
 278 #endif
 279
 280 /* Flags for skip_to_delim */
 281 #define SD_NOJMP        0x01    /* don't longjmp on fatal error. */
 282 #define SD_INVERT       0x02    /* look for chars NOT in passed set */
 283 #define SD_NOQUOTEDELIM 0x04    /* don't let single or double quotes act as delimiters */
 284 #define SD_NOSKIPCMD    0x08    /* don't skip over $(, <(, or >( command/process substitution */
 285 #define SD_EXTGLOB      0x10    /* skip over extended globbing patterns if appropriate */
 286 #define SD_IGNOREQUOTE  0x20    /* single and double quotes are not special */
 287 #define SD_GLOB         0x40    /* skip over glob patterns like bracket expressions */
 288
 289 extern int skip_to_delim __P((char *, int, char *, int));
 290
 291 #if defined (READLINE)
 292 extern int char_is_quoted __P((char *, int));
 293 extern int unclosed_pair __P((char *, int, char *));
 294 extern WORD_LIST *split_at_delims __P((char *, int, char *, int, int, int *, int *));
 295 #endif
 296
 297 /* Variables used to keep track of the characters in IFS. */
 298 extern SHELL_VAR *ifs_var;
 299 extern char *ifs_value;
 300 extern unsigned char ifs_cmap[];
 301
 302 #if defined (HANDLE_MULTIBYTE)
 303 extern unsigned char ifs_firstc[];
 304 extern size_t ifs_firstc_len;
 305 #else
 306 extern unsigned char ifs_firstc;
 307 #endif
 308
 309 /* Evaluates to 1 if C is a character in $IFS. */
 310 #define isifs(c)        (ifs_cmap[(unsigned char)(c)] != 0)
 311
 312 /* How to determine the quoted state of the character C. */
 313 #define QUOTED_CHAR(c)  ((c) == CTLESC)
 314
 315 /* Is the first character of STRING a quoted NULL character? */
 316 #define QUOTED_NULL(string) ((string)[0] == CTLNUL && (string)[1] == '\0')
 317
 318 #endif /* !_SUBST_H_ */