467 lines
12 KiB
C
467 lines
12 KiB
C
/* tilde.c -- Tilde expansion code (~/foo := $HOME/foo). */
|
||
|
||
/* Copyright (C) 1988,1989 Free Software Foundation, Inc.
|
||
|
||
This file is part of GNU Readline, a library for reading lines
|
||
of text with interactive input and history editing.
|
||
|
||
Readline 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 1, or (at your option) any
|
||
later version.
|
||
|
||
Readline 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 Readline; see the file COPYING. If not, write to the Free
|
||
Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
|
||
|
||
#if defined (HAVE_CONFIG_H)
|
||
# include <config.h>
|
||
#endif
|
||
|
||
#if defined (HAVE_UNISTD_H)
|
||
# ifdef _MINIX
|
||
# include <sys/types.h>
|
||
# endif
|
||
# include <unistd.h>
|
||
#endif
|
||
|
||
#if defined (HAVE_STRING_H)
|
||
# include <string.h>
|
||
#else /* !HAVE_STRING_H */
|
||
# include <strings.h>
|
||
#endif /* !HAVE_STRING_H */
|
||
|
||
#if defined (HAVE_STDLIB_H)
|
||
# include <stdlib.h>
|
||
#else
|
||
# include "ansi_stdlib.h"
|
||
#endif /* HAVE_STDLIB_H */
|
||
|
||
#include <sys/types.h>
|
||
#include <pwd.h>
|
||
|
||
#include "tilde.h"
|
||
|
||
#ifdef SHELL
|
||
#include "shell.h"
|
||
#endif
|
||
|
||
#if !defined (HAVE_GETPW_DECLS)
|
||
extern struct passwd *getpwuid (), *getpwnam ();
|
||
#endif /* !HAVE_GETPW_DECLS */
|
||
|
||
#if !defined (savestring)
|
||
extern char *xmalloc ();
|
||
# ifndef strcpy
|
||
extern char *strcpy ();
|
||
# endif
|
||
#define savestring(x) strcpy (xmalloc (1 + strlen (x)), (x))
|
||
#endif /* !savestring */
|
||
|
||
#if !defined (NULL)
|
||
# if defined (__STDC__)
|
||
# define NULL ((void *) 0)
|
||
# else
|
||
# define NULL 0x0
|
||
# endif /* !__STDC__ */
|
||
#endif /* !NULL */
|
||
|
||
#if defined (TEST) || defined (STATIC_MALLOC)
|
||
static char *xmalloc (), *xrealloc ();
|
||
#else
|
||
extern char *xmalloc (), *xrealloc ();
|
||
#endif /* TEST || STATIC_MALLOC */
|
||
|
||
/* The default value of tilde_additional_prefixes. This is set to
|
||
whitespace preceding a tilde so that simple programs which do not
|
||
perform any word separation get desired behaviour. */
|
||
static char *default_prefixes[] =
|
||
{ " ~", "\t~", (char *)NULL };
|
||
|
||
/* The default value of tilde_additional_suffixes. This is set to
|
||
whitespace or newline so that simple programs which do not
|
||
perform any word separation get desired behaviour. */
|
||
static char *default_suffixes[] =
|
||
{ " ", "\n", (char *)NULL };
|
||
|
||
/* If non-null, this contains the address of a function that the application
|
||
wants called before trying the standard tilde expansions. The function
|
||
is called with the text sans tilde, and returns a malloc()'ed string
|
||
which is the expansion, or a NULL pointer if the expansion fails. */
|
||
CPFunction *tilde_expansion_preexpansion_hook = (CPFunction *)NULL;
|
||
|
||
/* If non-null, this contains the address of a function to call if the
|
||
standard meaning for expanding a tilde fails. The function is called
|
||
with the text (sans tilde, as in "foo"), and returns a malloc()'ed string
|
||
which is the expansion, or a NULL pointer if there is no expansion. */
|
||
CPFunction *tilde_expansion_failure_hook = (CPFunction *)NULL;
|
||
|
||
/* When non-null, this is a NULL terminated array of strings which
|
||
are duplicates for a tilde prefix. Bash uses this to expand
|
||
`=~' and `:~'. */
|
||
char **tilde_additional_prefixes = default_prefixes;
|
||
|
||
/* When non-null, this is a NULL terminated array of strings which match
|
||
the end of a username, instead of just "/". Bash sets this to
|
||
`:' and `=~'. */
|
||
char **tilde_additional_suffixes = default_suffixes;
|
||
|
||
/* Find the start of a tilde expansion in STRING, and return the index of
|
||
the tilde which starts the expansion. Place the length of the text
|
||
which identified this tilde starter in LEN, excluding the tilde itself. */
|
||
static int
|
||
tilde_find_prefix (string, len)
|
||
char *string;
|
||
int *len;
|
||
{
|
||
register int i, j, string_len;
|
||
register char **prefixes = tilde_additional_prefixes;
|
||
|
||
string_len = strlen (string);
|
||
*len = 0;
|
||
|
||
if (*string == '\0' || *string == '~')
|
||
return (0);
|
||
|
||
if (prefixes)
|
||
{
|
||
for (i = 0; i < string_len; i++)
|
||
{
|
||
for (j = 0; prefixes[j]; j++)
|
||
{
|
||
if (strncmp (string + i, prefixes[j], strlen (prefixes[j])) == 0)
|
||
{
|
||
*len = strlen (prefixes[j]) - 1;
|
||
return (i + *len);
|
||
}
|
||
}
|
||
}
|
||
}
|
||
return (string_len);
|
||
}
|
||
|
||
/* Find the end of a tilde expansion in STRING, and return the index of
|
||
the character which ends the tilde definition. */
|
||
static int
|
||
tilde_find_suffix (string)
|
||
char *string;
|
||
{
|
||
register int i, j, string_len;
|
||
register char **suffixes;
|
||
|
||
suffixes = tilde_additional_suffixes;
|
||
string_len = strlen (string);
|
||
|
||
for (i = 0; i < string_len; i++)
|
||
{
|
||
if (string[i] == '/' /* || !string[i] */)
|
||
break;
|
||
|
||
for (j = 0; suffixes && suffixes[j]; j++)
|
||
{
|
||
if (strncmp (string + i, suffixes[j], strlen (suffixes[j])) == 0)
|
||
return (i);
|
||
}
|
||
}
|
||
return (i);
|
||
}
|
||
|
||
#if !defined (SHELL)
|
||
static char *
|
||
get_string_value (varname)
|
||
char *varname;
|
||
{
|
||
return ((char *)getenv (varname));
|
||
}
|
||
#endif
|
||
|
||
/* Return a new string which is the result of tilde expanding STRING. */
|
||
char *
|
||
tilde_expand (string)
|
||
char *string;
|
||
{
|
||
char *result;
|
||
int result_size, result_index;
|
||
|
||
result_index = result_size = 0;
|
||
if (result = strchr (string, '~'))
|
||
result = xmalloc (result_size = (strlen (string) + 16));
|
||
else
|
||
result = xmalloc (result_size = (strlen (string) + 1));
|
||
|
||
/* Scan through STRING expanding tildes as we come to them. */
|
||
while (1)
|
||
{
|
||
register int start, end;
|
||
char *tilde_word, *expansion;
|
||
int len;
|
||
|
||
/* Make START point to the tilde which starts the expansion. */
|
||
start = tilde_find_prefix (string, &len);
|
||
|
||
/* Copy the skipped text into the result. */
|
||
if ((result_index + start + 1) > result_size)
|
||
result = xrealloc (result, 1 + (result_size += (start + 20)));
|
||
|
||
strncpy (result + result_index, string, start);
|
||
result_index += start;
|
||
|
||
/* Advance STRING to the starting tilde. */
|
||
string += start;
|
||
|
||
/* Make END be the index of one after the last character of the
|
||
username. */
|
||
end = tilde_find_suffix (string);
|
||
|
||
/* If both START and END are zero, we are all done. */
|
||
if (!start && !end)
|
||
break;
|
||
|
||
/* Expand the entire tilde word, and copy it into RESULT. */
|
||
tilde_word = xmalloc (1 + end);
|
||
strncpy (tilde_word, string, end);
|
||
tilde_word[end] = '\0';
|
||
string += end;
|
||
|
||
expansion = tilde_expand_word (tilde_word);
|
||
free (tilde_word);
|
||
|
||
len = strlen (expansion);
|
||
if ((result_index + len + 1) > result_size)
|
||
result = xrealloc (result, 1 + (result_size += (len + 20)));
|
||
|
||
strcpy (result + result_index, expansion);
|
||
result_index += len;
|
||
free (expansion);
|
||
}
|
||
|
||
result[result_index] = '\0';
|
||
|
||
return (result);
|
||
}
|
||
|
||
/* Take FNAME and return the tilde prefix we want expanded. If LENP is
|
||
non-null, the index of the end of the prefix into FNAME is returned in
|
||
the location it points to. */
|
||
static char *
|
||
isolate_tilde_prefix (fname, lenp)
|
||
char *fname;
|
||
int *lenp;
|
||
{
|
||
char *ret;
|
||
int i;
|
||
|
||
ret = xmalloc (strlen (fname));
|
||
for (i = 1; fname[i] && fname[i] != '/'; i++)
|
||
ret[i - 1] = fname[i];
|
||
ret[i - 1] = '\0';
|
||
if (lenp)
|
||
*lenp = i;
|
||
return ret;
|
||
}
|
||
|
||
/* Return a string that is PREFIX concatenated with SUFFIX starting at
|
||
SUFFIND. */
|
||
static char *
|
||
glue_prefix_and_suffix (prefix, suffix, suffind)
|
||
char *prefix, *suffix;
|
||
int suffind;
|
||
{
|
||
char *ret;
|
||
int plen, slen;
|
||
|
||
plen = (prefix && *prefix) ? strlen (prefix) : 0;
|
||
slen = strlen (suffix + suffind);
|
||
ret = xmalloc (plen + slen + 1);
|
||
if (prefix && *prefix)
|
||
strcpy (ret, prefix);
|
||
strcpy (ret + plen, suffix + suffind);
|
||
return ret;
|
||
}
|
||
|
||
static char *
|
||
get_home_dir ()
|
||
{
|
||
char *home_dir;
|
||
|
||
#ifdef SHELL
|
||
home_dir = (char *)NULL;
|
||
if (current_user.home_dir == 0)
|
||
get_current_user_info ();
|
||
home_dir = current_user.home_dir;
|
||
#else
|
||
struct passwd *entry;
|
||
|
||
home_dir = (char *)NULL;
|
||
entry = getpwuid (getuid ());
|
||
if (entry)
|
||
home_dir = entry->pw_dir;
|
||
#endif
|
||
return (home_dir);
|
||
}
|
||
|
||
/* Do the work of tilde expansion on FILENAME. FILENAME starts with a
|
||
tilde. If there is no expansion, call tilde_expansion_failure_hook.
|
||
This always returns a newly-allocated string, never static storage. */
|
||
char *
|
||
tilde_expand_word (filename)
|
||
char *filename;
|
||
{
|
||
char *dirname, *expansion, *username;
|
||
int user_len;
|
||
struct passwd *user_entry;
|
||
|
||
if (filename == 0)
|
||
return ((char *)NULL);
|
||
|
||
if (*filename != '~')
|
||
return (savestring (filename));
|
||
|
||
/* A leading `~/' or a bare `~' is *always* translated to the value of
|
||
$HOME or the home directory of the current user, regardless of any
|
||
preexpansion hook. */
|
||
if (filename[1] == '\0' || filename[1] == '/')
|
||
{
|
||
/* Prefix $HOME to the rest of the string. */
|
||
expansion = get_string_value ("HOME");
|
||
|
||
/* If there is no HOME variable, look up the directory in
|
||
the password database. */
|
||
if (expansion == 0)
|
||
expansion = get_home_dir ();
|
||
|
||
return (glue_prefix_and_suffix (expansion, filename, 1));
|
||
}
|
||
|
||
username = isolate_tilde_prefix (filename, &user_len);
|
||
|
||
if (tilde_expansion_preexpansion_hook)
|
||
{
|
||
expansion = (*tilde_expansion_preexpansion_hook) (username);
|
||
if (expansion)
|
||
{
|
||
dirname = glue_prefix_and_suffix (expansion, filename, user_len);
|
||
free (username);
|
||
free (expansion);
|
||
return (dirname);
|
||
}
|
||
}
|
||
|
||
/* No preexpansion hook, or the preexpansion hook failed. Look in the
|
||
password database. */
|
||
dirname = (char *)NULL;
|
||
user_entry = getpwnam (username);
|
||
if (user_entry == 0)
|
||
{
|
||
/* If the calling program has a special syntax for expanding tildes,
|
||
and we couldn't find a standard expansion, then let them try. */
|
||
if (tilde_expansion_failure_hook)
|
||
{
|
||
expansion = (*tilde_expansion_failure_hook) (username);
|
||
if (expansion)
|
||
{
|
||
dirname = glue_prefix_and_suffix (expansion, filename, user_len);
|
||
free (expansion);
|
||
}
|
||
}
|
||
free (username);
|
||
/* If we don't have a failure hook, or if the failure hook did not
|
||
expand the tilde, return a copy of what we were passed. */
|
||
if (dirname == 0)
|
||
dirname = savestring (filename);
|
||
}
|
||
else
|
||
{
|
||
free (username);
|
||
dirname = glue_prefix_and_suffix (user_entry->pw_dir, filename, user_len);
|
||
}
|
||
|
||
endpwent ();
|
||
return (dirname);
|
||
}
|
||
|
||
|
||
#if defined (TEST)
|
||
#undef NULL
|
||
#include <stdio.h>
|
||
|
||
main (argc, argv)
|
||
int argc;
|
||
char **argv;
|
||
{
|
||
char *result, line[512];
|
||
int done = 0;
|
||
|
||
while (!done)
|
||
{
|
||
printf ("~expand: ");
|
||
fflush (stdout);
|
||
|
||
if (!gets (line))
|
||
strcpy (line, "done");
|
||
|
||
if ((strcmp (line, "done") == 0) ||
|
||
(strcmp (line, "quit") == 0) ||
|
||
(strcmp (line, "exit") == 0))
|
||
{
|
||
done = 1;
|
||
break;
|
||
}
|
||
|
||
result = tilde_expand (line);
|
||
printf (" --> %s\n", result);
|
||
free (result);
|
||
}
|
||
exit (0);
|
||
}
|
||
|
||
static void memory_error_and_abort ();
|
||
|
||
static char *
|
||
xmalloc (bytes)
|
||
int bytes;
|
||
{
|
||
char *temp = (char *)malloc (bytes);
|
||
|
||
if (!temp)
|
||
memory_error_and_abort ();
|
||
return (temp);
|
||
}
|
||
|
||
static char *
|
||
xrealloc (pointer, bytes)
|
||
char *pointer;
|
||
int bytes;
|
||
{
|
||
char *temp;
|
||
|
||
if (!pointer)
|
||
temp = (char *)malloc (bytes);
|
||
else
|
||
temp = (char *)realloc (pointer, bytes);
|
||
|
||
if (!temp)
|
||
memory_error_and_abort ();
|
||
|
||
return (temp);
|
||
}
|
||
|
||
static void
|
||
memory_error_and_abort ()
|
||
{
|
||
fprintf (stderr, "readline: out of virtual memory\n");
|
||
abort ();
|
||
}
|
||
|
||
/*
|
||
* Local variables:
|
||
* compile-command: "gcc -g -DTEST -o tilde tilde.c"
|
||
* end:
|
||
*/
|
||
#endif /* TEST */
|