xref: /titanic_41/usr/src/lib/libast/common/path/pathprog.c (revision d2b5b2d357ee3172eacb6860be1891259902203d)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1985-2010 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 *                   Phong Vo <kpv@research.att.com>                    *
20 *                                                                      *
21 ***********************************************************************/
22 #pragma prototyped
23 /*
24  * Glenn Fowler
25  * AT&T Research
26  *
27  * return the full path of the current program in path
28  * command!=0 is used as a default
29  */
30 
31 #include <ast.h>
32 
33 #if _WINIX
34 #include <ast_windows.h>
35 #include <ctype.h>
36 #endif
37 
38 #include "FEATURE/prog"
39 
40 static size_t
41 prog(const char* command, char* path, size_t size)
42 {
43 	ssize_t		n;
44 #if _WINIX || _lib_getexecname
45 	char*		s;
46 #endif
47 #if _WINIX
48 	char*		t;
49 	char*		e;
50 	int		c;
51 	int		q;
52 #endif
53 
54 #ifdef _PROC_PROG
55 	if ((n = readlink(_PROC_PROG, path, size)) > 0)
56 	{
57 		if (n < size)
58 			path[n] = 0;
59 		return n;
60 	}
61 #endif
62 #if _lib_getexecname
63 	if (s = (char*)getexecname())
64 	{
65 		n = strlen(s);
66 		if (n < size)
67 			strcpy(path, s);
68 		return n;
69 	}
70 #endif
71 #if _WINIX
72 	if (s = GetCommandLine())
73 	{
74 		n = 0;
75 		q = 0;
76 		t = path;
77 		e = path + size - 1;
78 		while (c = *s++)
79 		{
80 			if (c == q)
81 				q = 0;
82 			else if (!q && c == '"')
83 				q = c;
84 			else if (!q && isspace(c))
85 				break;
86 			else if (t < e)
87 				*t++ = c == '\\' ? '/' : c;
88 			else
89 				n++;
90 		}
91 		if (t < e)
92 			*t = 0;
93 		return (t - path) + n;
94 	}
95 #endif
96 	if (command)
97 	{
98 		if ((n = strlen(command) + 1) <= size)
99 			memcpy(path, command, n);
100 		return n;
101 	}
102 	return 0;
103 }
104 
105 size_t
106 pathprog(const char* command, char* path, size_t size)
107 {
108 	ssize_t		n;
109 	char		buf[PATH_MAX];
110 
111 	if ((n = prog(command, path, size)) > 0 && n <= size && *path != '/')
112 	{
113 		if (!pathpath(buf, path, NiL, PATH_REGULAR|PATH_EXECUTE))
114 			n = 0;
115 		else if ((n = strlen(buf) + 1) <= size)
116 			memcpy(path, buf, n);
117 	}
118 	return n;
119 }
120