xref: /titanic_41/usr/src/lib/libcmd/common/dirname.c (revision 634e26ec75c89095090605284938356a3145f2b8)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1992-2009 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 
31 static const char usage[] =
32 "[-?\n@(#)$Id: dirname (AT&T Research) 2009-01-31 $\n]"
33 USAGE_LICENSE
34 "[+NAME?dirname - return directory portion of file name]"
35 "[+DESCRIPTION?\bdirname\b treats \astring\a as a file name and returns "
36 	"the name of the directory containing the file name by deleting "
37 	"the last component from \astring\a.]"
38 "[+?If \astring\a consists solely of \b/\b characters the output will "
39 	"be a single \b/\b unless \bPATH_LEADING_SLASHES\b returned by "
40 	"\bgetconf\b(1) is \b1\b and \astring\a consists of multiple "
41 	"\b/\b characters in which case \b//\b will be output.  "
42 	"Otherwise, trailing \b/\b characters are removed, and if "
43 	"there are no remaining \b/\b characters in \astring\a, "
44 	"the string \b.\b will be written to standard output.  "
45 	"Otherwise, all characters following the last \b/\b are removed. "
46 	"If the remaining string consists solely of \b/\b characters, "
47 	"the output will be as if the original string had consisted solely "
48 	"as \b/\b characters as described above.  Otherwise, all "
49 	"trailing slashes are removed and the output will be this string "
50 	"unless this string is empty.  If empty the output will be \b.\b.]"
51 "[f:file?Print the \b$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 
66 static 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 
98 int
99 b_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