[thirdparty/bash.git] / lib / sh / shquote.c

/* shquote - functions to quote and dequote strings */

/* Copyright (C) 1999 Free Software Foundation, Inc.

   This file is part of GNU Bash, the Bourne Again SHell.

   Bash is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   Bash is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with Bash.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <config.h>

#if defined (HAVE_UNISTD_H)
#  ifdef _MINIX
#    include <sys/types.h>
#  endif
#  include <unistd.h>
#endif

#include <stdio.h>

#include "syntax.h"
#include <xmalloc.h>

/* Default set of characters that should be backslash-quoted in strings */
static const char bstab[256] =
  {
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 1, 1, 0, 0, 0, 0, 0,	/* TAB, NL */
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,

    1, 1, 1, 0, 1, 0, 1, 1,	/* SPACE, !, DQUOTE, DOL, AMP, SQUOTE */
    1, 1, 1, 0, 1, 0, 0, 0,	/* LPAR, RPAR, STAR, COMMA */
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 1, 1, 0, 1, 1,	/* SEMI, LESSTHAN, GREATERTHAN, QUEST */

    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 1, 1, 1, 1, 0,	/* LBRACK, BS, RBRACK, CARAT */

    1, 0, 0, 0, 0, 0, 0, 0,	/* BACKQ */
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 1, 1, 1, 0, 0,	/* LBRACE, BAR, RBRACE */

    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,

    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,

    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,

    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,
  };

/* **************************************************************** */
/*								    */
/*	 Functions for quoting strings to be re-read as input	    */
/*								    */
/* **************************************************************** */

/* Return a new string which is the single-quoted version of STRING.
   Used by alias and trap, among others. */
char *
sh_single_quote (string)
     const char *string;
{
  register int c;
  char *result, *r;
  const char *s;

  result = (char *)xmalloc (3 + (4 * strlen (string)));
  r = result;

  if (string[0] == '\'' && string[1] == 0)
    {
      *r++ = '\\';
      *r++ = '\'';
      *r++ = 0;
      return result;
    }

  *r++ = '\'';

  for (s = string; s && (c = *s); s++)
    {
      *r++ = c;

      if (c == '\'')
	{
	  *r++ = '\\';	/* insert escaped single quote */
	  *r++ = '\'';
	  *r++ = '\'';	/* start new quoted string */
	}
    }

  *r++ = '\'';
  *r = '\0';

  return (result);
}

/* Quote STRING using double quotes.  Return a new string. */
char *
sh_double_quote (string)
     const char *string;
{
  register unsigned char c;
  char *result, *r;
  const char *s;

  result = (char *)xmalloc (3 + (2 * strlen (string)));
  r = result;
  *r++ = '"';

  for (s = string; s && (c = *s); s++)
    {
      /* Backslash-newline disappears within double quotes, so don't add one. */
      if ((sh_syntaxtab[c] & CBSDQUOTE) && c != '\n')
	*r++ = '\\';
      else if (c == CTLESC || c == CTLNUL)
	*r++ = CTLESC;		/* could be '\\'? */

      *r++ = c;
    }

  *r++ = '"';
  *r = '\0';

  return (result);
}

/* Turn S into a simple double-quoted string.  If FLAGS is non-zero, quote
   double quote characters in S with backslashes. */
char *
sh_mkdoublequoted (s, slen, flags)
     const char *s;
     int slen, flags;
{
  char *r, *ret;
  int rlen;

  rlen = (flags == 0) ? slen + 3 : (2 * slen) + 1;
  ret = r = (char *)xmalloc (rlen);
  
  *r++ = '"';
  while (*s)
    {
      if (flags && *s == '"')
	*r++ = '\\';
      *r++ = *s++;
    }
  *r++ = '"';
  *r = '\0';

  return ret;
}

/* Remove backslashes that are quoting characters that are special between
   double quotes.  Return a new string.  XXX - should this handle CTLESC
   and CTLNUL? */
char *
sh_un_double_quote (string)
     char *string;
{
  register int c, pass_next;
  char *result, *r, *s;

  r = result = (char *)xmalloc (strlen (string) + 1);

  for (pass_next = 0, s = string; s && (c = *s); s++)
    {
      if (pass_next)
	{
	  *r++ = c;
	  pass_next = 0;
	  continue;
	}
      if (c == '\\' && (sh_syntaxtab[(unsigned char) s[1]] & CBSDQUOTE))
	{
	  pass_next = 1;
	  continue;
	}
      *r++ = c;
    }

  *r = '\0';
  return result;
}

/* Quote special characters in STRING using backslashes.  Return a new
   string.  NOTE:  if the string is to be further expanded, we need a
   way to protect the CTLESC and CTLNUL characters.  As I write this,
   the current callers will never cause the string to be expanded without
   going through the shell parser, which will protect the internal
   quoting characters.  TABLE, if set, points to a map of the ascii code
   set with char needing to be backslash-quoted if table[char]==1.  FLAGS,
   if 1, causes tildes to be quoted as well. */
   
char *
sh_backslash_quote (string, table, flags)
     char *string;
     char *table;
     int flags;
{
  int c;
  char *result, *r, *s, *backslash_table;

  result = (char *)xmalloc (2 * strlen (string) + 1);

  backslash_table = table ? table : (char *)bstab;
  for (r = result, s = string; s && (c = *s); s++)
    {
      if (backslash_table[c] == 1)
	*r++ = '\\';
      else if (c == '#' && s == string)			/* comment char */
	*r++ = '\\';
      else if ((flags&1) && c == '~' && (s == string || s[-1] == ':' || s[-1] == '='))
        /* Tildes are special at the start of a word or after a `:' or `='
	   (technically unquoted, but it doesn't make a difference in practice) */
	*r++ = '\\';
      *r++ = c;
    }

  *r = '\0';
  return (result);
}

#if defined (PROMPT_STRING_DECODE)
/* Quote characters that get special treatment when in double quotes in STRING
   using backslashes.  Return a new string. */
char *
sh_backslash_quote_for_double_quotes (string)
     char *string;
{
  unsigned char c;
  char *result, *r, *s;

  result = (char *)xmalloc (2 * strlen (string) + 1);

  for (r = result, s = string; s && (c = *s); s++)
    {
      if (sh_syntaxtab[c] & CBSDQUOTE)
	*r++ = '\\';
      /* I should probably add flags for these to sh_syntaxtab[] */
      else if (c == CTLESC || c == CTLNUL)
	*r++ = CTLESC;		/* could be '\\'? */

      *r++ = c;
    }

  *r = '\0';
  return (result);
}
#endif /* PROMPT_STRING_DECODE */

int
sh_contains_shell_metas (string)
     char *string;
{
  char *s;

  for (s = string; s && *s; s++)
    {
      switch (*s)
	{
	case ' ': case '\t': case '\n':		/* IFS white space */
	case '\'': case '"': case '\\':		/* quoting chars */
	case '|': case '&': case ';':		/* shell metacharacters */
	case '(': case ')': case '<': case '>':
	case '!': case '{': case '}':		/* reserved words */
	case '*': case '[': case '?': case ']':	/* globbing chars */
	case '^':
	case '$': case '`':			/* expansion chars */
	  return (1);
	case '~':				/* tilde expansion */
	  if (s == string || s[-1] == '=' || s[-1] == ':')
	    return (1);
	  break;
	case '#':
	  if (s == string)			/* comment char */
	    return (1);
	  /* FALLTHROUGH */
	default:
	  break;
	}
    }

  return (0);
}
Commit	Line	Data
2e4498b3 CR	1	/* shquote - functions to quote and dequote strings */
2e4498b3 CR	2
bb70624e JA	3	/* Copyright (C) 1999 Free Software Foundation, Inc.
	4
	5	This file is part of GNU Bash, the Bourne Again SHell.
	6
2e4498b3 CR	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	*/
bb70624e JA	20
	21	#include <config.h>
	22
	23	#if defined (HAVE_UNISTD_H)
	24	# ifdef _MINIX
	25	# include <sys/types.h>
	26	# endif
	27	# include <unistd.h>
	28	#endif
	29
	30	#include <stdio.h>
	31
28ef6c31	32	#include "syntax.h"
f73dda09	33	#include <xmalloc.h>
bb70624e	34
ddef12ff CR	35	/* Default set of characters that should be backslash-quoted in strings */
	36	static const char bstab[256] =
	37	{
	38	0, 0, 0, 0, 0, 0, 0, 0,
	39	0, 1, 1, 0, 0, 0, 0, 0, /* TAB, NL */
	40	0, 0, 0, 0, 0, 0, 0, 0,
	41	0, 0, 0, 0, 0, 0, 0, 0,
	42
	43	1, 1, 1, 0, 1, 0, 1, 1, /* SPACE, !, DQUOTE, DOL, AMP, SQUOTE */
	44	1, 1, 1, 0, 1, 0, 0, 0, /* LPAR, RPAR, STAR, COMMA */
	45	0, 0, 0, 0, 0, 0, 0, 0,
	46	0, 0, 0, 1, 1, 0, 1, 1, /* SEMI, LESSTHAN, GREATERTHAN, QUEST */
	47
	48	0, 0, 0, 0, 0, 0, 0, 0,
	49	0, 0, 0, 0, 0, 0, 0, 0,
	50	0, 0, 0, 0, 0, 0, 0, 0,
	51	0, 0, 0, 1, 1, 1, 1, 0, /* LBRACK, BS, RBRACK, CARAT */
	52
	53	1, 0, 0, 0, 0, 0, 0, 0, /* BACKQ */
	54	0, 0, 0, 0, 0, 0, 0, 0,
	55	0, 0, 0, 0, 0, 0, 0, 0,
	56	0, 0, 0, 1, 1, 1, 0, 0, /* LBRACE, BAR, RBRACE */
	57
	58	0, 0, 0, 0, 0, 0, 0, 0,
	59	0, 0, 0, 0, 0, 0, 0, 0,
	60	0, 0, 0, 0, 0, 0, 0, 0,
	61	0, 0, 0, 0, 0, 0, 0, 0,
	62
	63	0, 0, 0, 0, 0, 0, 0, 0,
	64	0, 0, 0, 0, 0, 0, 0, 0,
	65	0, 0, 0, 0, 0, 0, 0, 0,
	66	0, 0, 0, 0, 0, 0, 0, 0,
	67
	68	0, 0, 0, 0, 0, 0, 0, 0,
	69	0, 0, 0, 0, 0, 0, 0, 0,
	70	0, 0, 0, 0, 0, 0, 0, 0,
	71	0, 0, 0, 0, 0, 0, 0, 0,
	72
	73	0, 0, 0, 0, 0, 0, 0, 0,
	74	0, 0, 0, 0, 0, 0, 0, 0,
	75	0, 0, 0, 0, 0, 0, 0, 0,
	76	0, 0, 0, 0, 0, 0, 0, 0,
	77	};
	78
bb70624e JA	79	/* **************************************************************** */
	80	/* */
	81	/* Functions for quoting strings to be re-read as input */
	82	/* */
	83	/* **************************************************************** */
	84
	85	/* Return a new string which is the single-quoted version of STRING.
	86	Used by alias and trap, among others. */
	87	char *
28ef6c31	88	sh_single_quote (string)
18d2df91	89	const char *string;
bb70624e JA	90	{
bb70624e JA	91	register int c;
89c77bc7 CR	92	char result, r;
89c77bc7 CR	93	const char *s;
bb70624e	94
f73dda09	95	result = (char )xmalloc (3 + (4 strlen (string)));
bb70624e	96	r = result;
1442f67c CR	97
	98	if (string[0] == '\'' && string[1] == 0)
	99	{
	100	*r++ = '\\';
	101	*r++ = '\'';
	102	*r++ = 0;
	103	return result;
	104	}
	105
bb70624e JA	106	*r++ = '\'';
	107
	108	for (s = string; s && (c = *s); s++)
	109	{
	110	*r++ = c;
	111
	112	if (c == '\'')
	113	{
	114	r++ = '\\'; / insert escaped single quote */
	115	*r++ = '\'';
	116	r++ = '\''; / start new quoted string */
	117	}
	118	}
	119
	120	*r++ = '\'';
	121	*r = '\0';
	122
	123	return (result);
	124	}
	125
	126	/* Quote STRING using double quotes. Return a new string. */
	127	char *
28ef6c31	128	sh_double_quote (string)
18d2df91	129	const char *string;
bb70624e	130	{
f73dda09	131	register unsigned char c;
89c77bc7 CR	132	char result, r;
89c77bc7 CR	133	const char *s;
bb70624e	134
f73dda09	135	result = (char )xmalloc (3 + (2 strlen (string)));
bb70624e JA	136	r = result;
	137	*r++ = '"';
	138
	139	for (s = string; s && (c = *s); s++)
	140	{
da719982 CR	141	/* Backslash-newline disappears within double quotes, so don't add one. */
da719982 CR	142	if ((sh_syntaxtab[c] & CBSDQUOTE) && c != '\n')
28ef6c31	143	*r++ = '\\';
d3a24ed2 CR	144	else if (c == CTLESC \|\| c == CTLNUL)
d3a24ed2 CR	145	r++ = CTLESC; / could be '\\'? */
28ef6c31 JA	146
28ef6c31 JA	147	*r++ = c;
bb70624e JA	148	}
	149
	150	*r++ = '"';
	151	*r = '\0';
	152
	153	return (result);
	154	}
	155
c3271763 CR	156	/* Turn S into a simple double-quoted string. If FLAGS is non-zero, quote
	157	double quote characters in S with backslashes. */
	158	char *
	159	sh_mkdoublequoted (s, slen, flags)
	160	const char *s;
	161	int slen, flags;
	162	{
	163	char r, ret;
	164	int rlen;
	165
	166	rlen = (flags == 0) ? slen + 3 : (2 * slen) + 1;
	167	ret = r = (char *)xmalloc (rlen);
	168
	169	*r++ = '"';
	170	while (*s)
	171	{
	172	if (flags && *s == '"')
	173	*r++ = '\\';
	174	r++ = s++;
	175	}
	176	*r++ = '"';
	177	*r = '\0';
	178
	179	return ret;
	180	}
	181
bb70624e	182	/* Remove backslashes that are quoting characters that are special between
d3a24ed2 CR	183	double quotes. Return a new string. XXX - should this handle CTLESC
d3a24ed2 CR	184	and CTLNUL? */
bb70624e	185	char *
28ef6c31	186	sh_un_double_quote (string)
bb70624e JA	187	char *string;
	188	{
	189	register int c, pass_next;
	190	char result, r, *s;
	191
f73dda09	192	r = result = (char *)xmalloc (strlen (string) + 1);
bb70624e JA	193
	194	for (pass_next = 0, s = string; s && (c = *s); s++)
	195	{
	196	if (pass_next)
	197	{
	198	*r++ = c;
	199	pass_next = 0;
	200	continue;
	201	}
f73dda09	202	if (c == '\\' && (sh_syntaxtab[(unsigned char) s[1]] & CBSDQUOTE))
bb70624e JA	203	{
	204	pass_next = 1;
	205	continue;
	206	}
	207	*r++ = c;
	208	}
	209
	210	*r = '\0';
	211	return result;
	212	}
	213
	214	/* Quote special characters in STRING using backslashes. Return a new
633e5c6d CR	215	string. NOTE: if the string is to be further expanded, we need a
	216	way to protect the CTLESC and CTLNUL characters. As I write this,
	217	the current callers will never cause the string to be expanded without
	218	going through the shell parser, which will protect the internal
8360b906 CR	219	quoting characters. TABLE, if set, points to a map of the ascii code
	220	set with char needing to be backslash-quoted if table[char]==1. FLAGS,
	221	if 1, causes tildes to be quoted as well. */
	222
bb70624e	223	char *
8360b906	224	sh_backslash_quote (string, table, flags)
bb70624e	225	char *string;
ddef12ff	226	char *table;
8360b906	227	int flags;
bb70624e JA	228	{
bb70624e JA	229	int c;
ddef12ff	230	char result, r, s, backslash_table;
bb70624e	231
f73dda09	232	result = (char )xmalloc (2 strlen (string) + 1);
bb70624e	233
f14388d3	234	backslash_table = table ? table : (char *)bstab;
bb70624e JA	235	for (r = result, s = string; s && (c = *s); s++)
bb70624e JA	236	{
ddef12ff CR	237	if (backslash_table[c] == 1)
	238	*r++ = '\\';
	239	else if (c == '#' && s == string) /* comment char */
	240	*r++ = '\\';
8360b906	241	else if ((flags&1) && c == '~' && (s == string \|\| s[-1] == ':' \|\| s[-1] == '='))
863d31ae CR	242	/* Tildes are special at the start of a word or after a `:' or `='
	243	(technically unquoted, but it doesn't make a difference in practice) */
	244	*r++ = '\\';
ddef12ff	245	*r++ = c;
bb70624e JA	246	}
	247
	248	*r = '\0';
	249	return (result);
	250	}
	251
28ef6c31 JA	252	#if defined (PROMPT_STRING_DECODE)
	253	/* Quote characters that get special treatment when in double quotes in STRING
	254	using backslashes. Return a new string. */
	255	char *
	256	sh_backslash_quote_for_double_quotes (string)
	257	char *string;
	258	{
f73dda09	259	unsigned char c;
28ef6c31 JA	260	char result, r, *s;
28ef6c31 JA	261
f73dda09	262	result = (char )xmalloc (2 strlen (string) + 1);
28ef6c31 JA	263
	264	for (r = result, s = string; s && (c = *s); s++)
	265	{
	266	if (sh_syntaxtab[c] & CBSDQUOTE)
	267	*r++ = '\\';
d3a24ed2 CR	268	/* I should probably add flags for these to sh_syntaxtab[] */
	269	else if (c == CTLESC \|\| c == CTLNUL)
	270	r++ = CTLESC; / could be '\\'? */
28ef6c31 JA	271
	272	*r++ = c;
	273	}
	274
	275	*r = '\0';
	276	return (result);
	277	}
	278	#endif /* PROMPT_STRING_DECODE */
	279
bb70624e	280	int
28ef6c31	281	sh_contains_shell_metas (string)
bb70624e JA	282	char *string;
	283	{
	284	char *s;
	285
	286	for (s = string; s && *s; s++)
	287	{
	288	switch (*s)
	289	{
	290	case ' ': case '\t': case '\n': /* IFS white space */
	291	case '\'': case '"': case '\\': /* quoting chars */
	292	case '\|': case '&': case ';': /* shell metacharacters */
	293	case '(': case ')': case '<': case '>':
	294	case '!': case '{': case '}': /* reserved words */
	295	case '': case '[': case '?': case ']': / globbing chars */
	296	case '^':
	297	case '$': case '`': /* expansion chars */
	298	return (1);
	299	case '~': /* tilde expansion */
	300	if (s == string \|\| s[-1] == '=' \|\| s[-1] == ':')
	301	return (1);
f73dda09	302	break;
bb70624e JA	303	case '#':
	304	if (s == string) /* comment char */
	305	return (1);
	306	/* FALLTHROUGH */
	307	default:
	308	break;
	309	}
	310	}
	311
	312	return (0);
	313	}