illumos-port-bash/examples/loadables/dirname.c

120 lines
3.1 KiB
C

/* dirname - return directory portion of pathname */
/* See Makefile for compilation details. */
/*
Copyright (C) 1999-2009 Free Software Foundation, Inc.
This file is part of GNU Bash.
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)
# include <unistd.h>
#endif
#include <stdio.h>
#include "builtins.h"
#include "shell.h"
#include "common.h"
#include "bashgetopt.h"
int
dirname_builtin (list)
WORD_LIST *list;
{
int slen;
char *string;
if (no_options (list))
return (EX_USAGE);
list = loptend;
if (list == 0 || list->next)
{
builtin_usage ();
return (EX_USAGE);
}
string = list->word->word;
slen = strlen (string);
/* Strip trailing slashes */
while (slen > 0 && string[slen - 1] == '/')
slen--;
/* (2) If string consists entirely of slash characters, string shall be
set to a single slash character. In this case, skip steps (3)
through (8). */
if (slen == 0)
{
fputs ("/\n", stdout);
return (EXECUTION_SUCCESS);
}
/* (3) If there are any trailing slash characters in string, they
shall be removed. */
string[slen] = '\0';
/* (4) If there are no slash characters remaining in string, string
shall be set to a single period character. In this case, skip
steps (5) through (8).
(5) If there are any trailing nonslash characters in string,
they shall be removed. */
while (--slen >= 0)
if (string[slen] == '/')
break;
if (slen < 0)
{
fputs (".\n", stdout);
return (EXECUTION_SUCCESS);
}
/* (7) If there are any trailing slash characters in string, they
shall be removed. */
while (--slen >= 0)
if (string[slen] != '/')
break;
string[++slen] = '\0';
/* (8) If the remaining string is empty, string shall be set to a single
slash character. */
printf ("%s\n", (slen == 0) ? "/" : string);
return (EXECUTION_SUCCESS);
}
char *dirname_doc[] = {
"Display directory portion of pathname.",
"",
"The STRING is converted to the name of the directory containing",
"the filename corresponding to the last pathname component in STRING.",
(char *)NULL
};
/* The standard structure describing a builtin command. bash keeps an array
of these structures. */
struct builtin dirname_struct = {
"dirname", /* builtin name */
dirname_builtin, /* function implementing the builtin */
BUILTIN_ENABLED, /* initial flags for builtin */
dirname_doc, /* array of long documentation strings. */
"dirname string", /* usage synopsis */
0 /* reserved for internal use */
};