1/***********************************************************************
2*                                                                      *
3*               This software is part of the ast package               *
4*          Copyright (c) 1992-2010 AT&T Intellectual Property          *
5*                      and is licensed under the                       *
6*                  Common Public License, Version 1.0                  *
7*                    by AT&T Intellectual Property                     *
8*                                                                      *
9*                A copy of the License is available at                 *
10*            http://www.opensource.org/licenses/cpl1.0.txt             *
11*         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12*                                                                      *
13*              Information and Software Systems Research               *
14*                            AT&T Research                             *
15*                           Florham Park NJ                            *
16*                                                                      *
17*                 Glenn Fowler <gsf@research.att.com>                  *
18*                  David Korn <dgk@research.att.com>                   *
19*                                                                      *
20***********************************************************************/
21#pragma prototyped
22/*
23 * David Korn
24 * AT&T Bell Laboratories
25 *
26 * dirname path [suffix]
27 *
28 * print the dirname of a pathname
29 */
30
31static const char usage[] =
32"[-?\n@(#)$Id: dirname (AT&T Research) 2009-01-31 $\n]"
33USAGE_LICENSE
34"[+NAME?dirname - return directory portion of file name]"
35"[+DESCRIPTION?\bdirname\b treats \astring\a as a file name and returns "
36	"the name of the directory containing the file name by deleting "
37	"the last component from \astring\a.]"
38"[+?If \astring\a consists solely of \b/\b characters the output will "
39	"be a single \b/\b unless \bPATH_LEADING_SLASHES\b returned by "
40	"\bgetconf\b(1) is \b1\b and \astring\a consists of multiple "
41	"\b/\b characters in which case \b//\b will be output.  "
42	"Otherwise, trailing \b/\b characters are removed, and if "
43	"there are no remaining \b/\b characters in \astring\a, "
44	"the string \b.\b will be written to standard output.  "
45	"Otherwise, all characters following the last \b/\b are removed. "
46	"If the remaining string consists solely of \b/\b characters, "
47	"the output will be as if the original string had consisted solely "
48	"as \b/\b characters as described above.  Otherwise, all "
49	"trailing slashes are removed and the output will be this string "
50	"unless this string is empty.  If empty the output will be \b.\b.]"
51"[f:file?Print the \b$PATH\b relative regular file path for \astring\a.]"
52"[r:relative?Print the \b$PATH\b relative readable file path for \astring\a.]"
53"[x:executable?Print the \b$PATH\b relative executable file path for \astring\a.]"
54"\n"
55"\nstring\n"
56"\n"
57"[+EXIT STATUS?]{"
58        "[+0?Successful Completion.]"
59        "[+>0?An error occurred.]"
60"}"
61"[+SEE ALSO?\bbasename\b(1), \bgetconf\b(1), \bdirname\b(3), \bpathname\b(3)]"
62;
63
64#include <cmd.h>
65
66static void l_dirname(register Sfio_t *outfile, register const char *pathname)
67{
68	register const char  *last;
69	/* go to end of path */
70	for(last=pathname; *last; last++);
71	/* back over trailing '/' */
72	while(last>pathname && *--last=='/');
73	/* back over non-slash chars */
74	for(;last>pathname && *last!='/';last--);
75	if(last==pathname)
76	{
77		/* all '/' or "" */
78		if(*pathname!='/')
79			last = pathname = ".";
80	}
81	else
82	{
83		/* back over trailing '/' */
84		for(;*last=='/' && last > pathname; last--);
85	}
86	/* preserve // */
87	if(last!=pathname && pathname[0]=='/' && pathname[1]=='/')
88	{
89		while(pathname[2]=='/' && pathname<last)
90			pathname++;
91		if(last!=pathname && pathname[0]=='/' && pathname[1]=='/' && *astconf("PATH_LEADING_SLASHES",NiL,NiL)!='1')
92			pathname++;
93	}
94	sfwrite(outfile,pathname,last+1-pathname);
95	sfputc(outfile,'\n');
96}
97
98int
99b_dirname(int argc,register char *argv[], void* context)
100{
101	register int n;
102	int mode = 0;
103	char buf[PATH_MAX];
104
105	cmdinit(argc, argv, context, ERROR_CATALOG, 0);
106	while (n = optget(argv, usage)) switch (n)
107	{
108	case 'f':
109		mode |= PATH_REGULAR;
110		break;
111	case 'r':
112		mode &= ~PATH_REGULAR;
113		mode |= PATH_READ;
114		break;
115	case 'x':
116		mode |= PATH_EXECUTE;
117		break;
118	case ':':
119		error(2, "%s", opt_info.arg);
120		break;
121	case '?':
122		error(ERROR_usage(2), "%s", opt_info.arg);
123		break;
124	}
125	argv += opt_info.index;
126	argc -= opt_info.index;
127	if(error_info.errors || argc != 1)
128		error(ERROR_usage(2),"%s", optusage(NiL));
129	if(!mode)
130		l_dirname(sfstdout,argv[0]);
131	else if(pathpath(buf, argv[0], "", mode))
132		sfputr(sfstdout, buf, '\n');
133	else
134		error(1|ERROR_WARNING, "%s: relative path not found", argv[0]);
135	return(0);
136}
137