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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	lib/libc/stdlib/realpath.c	Lines:	0	95	0.0 %
Date:	2017-11-13	Branches:	0	63	0.0 %


/*	$OpenBSD: realpath.c,v 1.21 2016/08/28 04:08:59 guenther Exp $ */
/*
 * Copyright (c) 2003 Constantin S. Svintsoff <kostik@iclub.nsu.ru>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The names of the authors may not be used to endorse or promote
 *    products derived from this software without specific prior written
 *    permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <limits.h>

/* A slightly modified copy of this file exists in libexec/ld.so */

/*
 * char *realpath(const char *path, char resolved[PATH_MAX]);
 *
 * Find the real name of path, by removing all ".", ".." and symlink
 * components.  Returns (resolved) on success, or (NULL) on failure,
 * in which case the path which caused trouble is left in (resolved).
 */
char *
realpath(const char *path, char *resolved)
{
	char *p, *q, *s;
	size_t left_len, resolved_len;
	unsigned symlinks;
	int serrno, slen, mem_allocated;
	char left[PATH_MAX], next_token[PATH_MAX], symlink[PATH_MAX];

	if (path[0] == '\0') {
		errno = ENOENT;
		return (NULL);
	}

	serrno = errno;

	if (resolved == NULL) {
		resolved = malloc(PATH_MAX);
		if (resolved == NULL)
			return (NULL);
		mem_allocated = 1;
	} else
		mem_allocated = 0;

	symlinks = 0;
	if (path[0] == '/') {
		resolved[0] = '/';
		resolved[1] = '\0';
		if (path[1] == '\0')
			return (resolved);
		resolved_len = 1;
		left_len = strlcpy(left, path + 1, sizeof(left));
	} else {
		if (getcwd(resolved, PATH_MAX) == NULL) {
			if (mem_allocated)
				free(resolved);
			else
				strlcpy(resolved, ".", PATH_MAX);
			return (NULL);
		}
		resolved_len = strlen(resolved);
		left_len = strlcpy(left, path, sizeof(left));
	}
	if (left_len >= sizeof(left) || resolved_len >= PATH_MAX) {
		errno = ENAMETOOLONG;
		goto err;
	}

	/*
	 * Iterate over path components in `left'.
	 */
	while (left_len != 0) {
		/*
		 * Extract the next path component and adjust `left'
		 * and its length.
		 */
		p = strchr(left, '/');
		s = p ? p : left + left_len;
		if (s - left >= sizeof(next_token)) {
			errno = ENAMETOOLONG;
			goto err;
		}
		memcpy(next_token, left, s - left);
		next_token[s - left] = '\0';
		left_len -= s - left;
		if (p != NULL)
			memmove(left, s + 1, left_len + 1);
		if (resolved[resolved_len - 1] != '/') {
			if (resolved_len + 1 >= PATH_MAX) {
				errno = ENAMETOOLONG;
				goto err;
			}
			resolved[resolved_len++] = '/';
			resolved[resolved_len] = '\0';
		}
		if (next_token[0] == '\0')
			continue;
		else if (strcmp(next_token, ".") == 0)
			continue;
		else if (strcmp(next_token, "..") == 0) {
			/*
			 * Strip the last path component except when we have
			 * single "/"
			 */
			if (resolved_len > 1) {
				resolved[resolved_len - 1] = '\0';
				q = strrchr(resolved, '/') + 1;
				*q = '\0';
				resolved_len = q - resolved;
			}
			continue;
		}

		/*
		 * Append the next path component and lstat() it. If
		 * lstat() fails we still can return successfully if
		 * there are no more path components left.
		 */
		resolved_len = strlcat(resolved, next_token, PATH_MAX);
		if (resolved_len >= PATH_MAX) {
			errno = ENAMETOOLONG;
			goto err;
		}
		slen = readlink(resolved, symlink, sizeof(symlink) - 1);
		if (slen < 0) {
			switch (errno) {
			case EINVAL:
				/* not a symlink, continue to next component */
				continue;
			case ENOENT:
				if (p == NULL) {
					errno = serrno;
					return (resolved);
				}
				/* FALLTHROUGH */
			default:
				goto err;
			}
		} else {
			if (symlinks++ > SYMLOOP_MAX) {
				errno = ELOOP;
				goto err;
			}

			symlink[slen] = '\0';
			if (symlink[0] == '/') {
				resolved[1] = 0;
				resolved_len = 1;
			} else if (resolved_len > 1) {
				/* Strip the last path component. */
				resolved[resolved_len - 1] = '\0';
				q = strrchr(resolved, '/') + 1;
				*q = '\0';
				resolved_len = q - resolved;
			}

			/*
			 * If there are any path components left, then
			 * append them to symlink. The result is placed
			 * in `left'.
			 */
			if (p != NULL) {
				if (symlink[slen - 1] != '/') {
					if (slen + 1 >= sizeof(symlink)) {
						errno = ENAMETOOLONG;
						goto err;
					}
					symlink[slen] = '/';
					symlink[slen + 1] = 0;
				}
				left_len = strlcat(symlink, left, sizeof(symlink));
				if (left_len >= sizeof(symlink)) {
					errno = ENAMETOOLONG;
					goto err;
				}
			}
			left_len = strlcpy(left, symlink, sizeof(left));
		}
	}

	/*
	 * Remove trailing slash except when the resolved pathname
	 * is a single "/".
	 */
	if (resolved_len > 1 && resolved[resolved_len - 1] == '/')
		resolved[resolved_len - 1] = '\0';
	return (resolved);

err:
	if (mem_allocated)
		free(resolved);
	return (NULL);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: realpath.c,v 1.21 2016/08/28 04:08:59 guenther Exp $ */
2			/*
3			* Copyright (c) 2003 Constantin S. Svintsoff <kostik@iclub.nsu.ru>
4			*
5			* Redistribution and use in source and binary forms, with or without
6			* modification, are permitted provided that the following conditions
7			* are met:
8			* 1. Redistributions of source code must retain the above copyright
9			* notice, this list of conditions and the following disclaimer.
10			* 2. Redistributions in binary form must reproduce the above copyright
11			* notice, this list of conditions and the following disclaimer in the
12			* documentation and/or other materials provided with the distribution.
13			* 3. The names of the authors may not be used to endorse or promote
14			* products derived from this software without specific prior written
15			* permission.
16			*
17			* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18			* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20			* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21			* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23			* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27			* SUCH DAMAGE.
28			*/
29
30			#include <errno.h>
31			#include <stdlib.h>
32			#include <string.h>
33			#include <unistd.h>
34			#include <limits.h>
35
36			/* A slightly modified copy of this file exists in libexec/ld.so */
37
38			/*
39			* char realpath(const char path, char resolved[PATH_MAX]);
40			*
41			* Find the real name of path, by removing all ".", ".." and symlink
42			* components. Returns (resolved) on success, or (NULL) on failure,
43			* in which case the path which caused trouble is left in (resolved).
44			*/
45			char *
46			realpath(const char path, char resolved)
47			{
48			char p, q, *s;
49			size_t left_len, resolved_len;
50			unsigned symlinks;
51			int serrno, slen, mem_allocated;
52			char left[PATH_MAX], next_token[PATH_MAX], symlink[PATH_MAX];
53
54			if (path[0] == '\0') {
55			errno = ENOENT;
56			return (NULL);
57			}
58
59			serrno = errno;
60
61			if (resolved == NULL) {
62			resolved = malloc(PATH_MAX);
63			if (resolved == NULL)
64			return (NULL);
65			mem_allocated = 1;
66			} else
67			mem_allocated = 0;
68
69			symlinks = 0;
70			if (path[0] == '/') {
71			resolved[0] = '/';
72			resolved[1] = '\0';
73			if (path[1] == '\0')
74			return (resolved);
75			resolved_len = 1;
76			left_len = strlcpy(left, path + 1, sizeof(left));
77			} else {
78			if (getcwd(resolved, PATH_MAX) == NULL) {
79			if (mem_allocated)
80			free(resolved);
81			else
82			strlcpy(resolved, ".", PATH_MAX);
83			return (NULL);
84			}
85			resolved_len = strlen(resolved);
86			left_len = strlcpy(left, path, sizeof(left));
87			}
88			if (left_len >= sizeof(left) \|\| resolved_len >= PATH_MAX) {
89			errno = ENAMETOOLONG;
90			goto err;
91			}
92
93			/*
94			* Iterate over path components in `left'.
95			*/
96			while (left_len != 0) {
97			/*
98			* Extract the next path component and adjust `left'
99			* and its length.
100			*/
101			p = strchr(left, '/');
102			s = p ? p : left + left_len;
103			if (s - left >= sizeof(next_token)) {
104			errno = ENAMETOOLONG;
105			goto err;
106			}
107			memcpy(next_token, left, s - left);
108			next_token[s - left] = '\0';
109			left_len -= s - left;
110			if (p != NULL)
111			memmove(left, s + 1, left_len + 1);
112			if (resolved[resolved_len - 1] != '/') {
113			if (resolved_len + 1 >= PATH_MAX) {
114			errno = ENAMETOOLONG;
115			goto err;
116			}
117			resolved[resolved_len++] = '/';
118			resolved[resolved_len] = '\0';
119			}
120			if (next_token[0] == '\0')
121			continue;
122			else if (strcmp(next_token, ".") == 0)
123			continue;
124			else if (strcmp(next_token, "..") == 0) {
125			/*
126			* Strip the last path component except when we have
127			* single "/"
128			*/
129			if (resolved_len > 1) {
130			resolved[resolved_len - 1] = '\0';
131			q = strrchr(resolved, '/') + 1;
132			*q = '\0';
133			resolved_len = q - resolved;
134			}
135			continue;
136			}
137
138			/*
139			* Append the next path component and lstat() it. If
140			* lstat() fails we still can return successfully if
141			* there are no more path components left.
142			*/
143			resolved_len = strlcat(resolved, next_token, PATH_MAX);
144			if (resolved_len >= PATH_MAX) {
145			errno = ENAMETOOLONG;
146			goto err;
147			}
148			slen = readlink(resolved, symlink, sizeof(symlink) - 1);
149			if (slen < 0) {
150			switch (errno) {
151			case EINVAL:
152			/* not a symlink, continue to next component */
153			continue;
154			case ENOENT:
155			if (p == NULL) {
156			errno = serrno;
157			return (resolved);
158			}
159			/* FALLTHROUGH */
160			default:
161			goto err;
162			}
163			} else {
164			if (symlinks++ > SYMLOOP_MAX) {
165			errno = ELOOP;
166			goto err;
167			}
168
169			symlink[slen] = '\0';
170			if (symlink[0] == '/') {
171			resolved[1] = 0;
172			resolved_len = 1;
173			} else if (resolved_len > 1) {
174			/* Strip the last path component. */
175			resolved[resolved_len - 1] = '\0';
176			q = strrchr(resolved, '/') + 1;
177			*q = '\0';
178			resolved_len = q - resolved;
179			}
180
181			/*
182			* If there are any path components left, then
183			* append them to symlink. The result is placed
184			* in `left'.
185			*/
186			if (p != NULL) {
187			if (symlink[slen - 1] != '/') {
188			if (slen + 1 >= sizeof(symlink)) {
189			errno = ENAMETOOLONG;
190			goto err;
191			}
192			symlink[slen] = '/';
193			symlink[slen + 1] = 0;
194			}
195			left_len = strlcat(symlink, left, sizeof(symlink));
196			if (left_len >= sizeof(symlink)) {
197			errno = ENAMETOOLONG;
198			goto err;
199			}
200			}
201			left_len = strlcpy(left, symlink, sizeof(left));
202			}
203			}
204
205			/*
206			* Remove trailing slash except when the resolved pathname
207			* is a single "/".
208			*/
209			if (resolved_len > 1 && resolved[resolved_len - 1] == '/')
210			resolved[resolved_len - 1] = '\0';
211			return (resolved);
212
213			err:
214			if (mem_allocated)
215			free(resolved);
216			return (NULL);
217			}