1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
|
/*
+----------------------------------------------------------------------+
| PHP version 4.0 |
+----------------------------------------------------------------------+
| Copyright (c) 1997, 1998, 1999, 2000 The PHP Group |
+----------------------------------------------------------------------+
| This source file is subject to version 2.01 of the PHP license, |
| that is bundled with this package in the file LICENSE, and is |
| available at through the world-wide-web at |
| http://www.php.net/license/2_01.txt. |
| If you did not receive a copy of the PHP license and are unable to |
| obtain it through the world-wide-web, please send a note to |
| license@php.net so we can mail you a copy immediately. |
+----------------------------------------------------------------------+
| Author: Sander Steffann (sander@steffann.nl) |
+----------------------------------------------------------------------+
*/
#include "php.h"
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/stat.h>
#ifndef MAXSYMLINKS
#define MAXSYMLINKS 32
#endif
#ifndef S_ISDIR
#define S_ISDIR(mode) (((mode)&S_IFMT) == S_IFDIR)
#endif
char *php_realpath(char *path, char resolved_path[]);
char *php_realpath(char *path, char resolved_path []) {
char path_construction[MAXPATHLEN]; /* We build the result in here */
char *writepos; /* Position to write next char */
char path_copy[MAXPATHLEN]; /* A work-copy of the path */
char *workpos; /* working position in *path */
#if !defined(PHP_WIN32)
char buf[MAXPATHLEN]; /* Buffer for readlink */
int linklength; /* The result from readlink */
#endif
int linkcount = 0; /* Count symlinks to avoid loops */
struct stat filestat; /* result from stat */
#ifdef PHP_WIN32
char *temppos; /* position while counting '.' */
int dotcount; /* number of '.' */
int t; /* counter */
#endif
/* Set the work-position to the beginning of the given path */
strcpy(path_copy, path);
workpos = path_copy;
#ifdef PHP_WIN32
/* Find out where we start - Windows version */
if ((*workpos == '\\') || (*workpos == '/')) {
/* We start at the root of the current drive */
/* Get the current directory */
if (V_GETCWD(path_construction, MAXPATHLEN-1) == NULL) {
/* Unable to get cwd */
resolved_path[0] = 0;
return NULL;
}
/* We only need the first three chars (for example "C:\") */
path_construction[3] = 0;
workpos++;
} else if (workpos[1] == ':') {
/* A drive-letter is specified, copy it */
strncpy(path_construction, path, 2);
strcat(path_construction, "\\");
workpos++;
workpos++;
} else {
/* Use the current directory */
if (V_GETCWD(path_construction, MAXPATHLEN-1) == NULL) {
/* Unable to get cwd */
resolved_path[0] = 0;
return NULL;
}
strcat(path_construction, "\\");
}
#else
/* Find out where we start - Unix version */
if (*workpos == '/') {
/* We start at the root */
strcpy(path_construction, "/");
workpos++;
} else {
/* Use the current directory */
if (V_GETCWD(path_construction, MAXPATHLEN-1) == NULL) {
/* Unable to get cwd */
resolved_path[0] = 0;
return NULL;
}
strcat(path_construction, "/");
}
#endif
/* Set the next-char-position */
writepos = &path_construction[strlen(path_construction)];
/* Go to the end, then stop */
while(*workpos != 0) {
/* Strip (back)slashes */
#ifdef PHP_WIN32
while(*workpos == '\\') workpos++;
#else
while(*workpos == '/') workpos++;
#endif
#ifdef PHP_WIN32
/* reset dotcount */
dotcount = 0;
/* Look for .. */
if ((workpos[0] == '.') && (workpos[1] != 0)) {
/* Windows accepts \...\ as \..\..\, \....\ as \..\..\..\, etc */
/* At least Win98 does */
temppos = workpos;
while(*temppos++ == '.') {
dotcount++;
if ((*temppos != '\\') && (*temppos != 0) && (*temppos != '.')) {
/* This is not a /../ component, but a filename that starts with '.' */
dotcount = 0;
}
}
/* Go back dotcount-1 times */
for (t=0 ; t<(dotcount-1) ; t++) {
workpos++; /* move to next '.' */
/* Can we still go back? */
if ((writepos-3) <= path_construction) return NULL;
/* Go back */
writepos--; /* move to '\' */
while(*--writepos != '\\') ; /* skip until previous '\\' */
}
}
/* No special case */
if (dotcount == 0) {
/* Append */
while((*workpos != '\\') && (*workpos != 0)) {
*writepos++ = *workpos++;
}
}
/* Just one '.', go to next element */
if (dotcount == 1) {
while((*workpos != '\\') && (*workpos != 0)) {
*workpos++;
}
/* Avoid double \ in the result */
writepos--;
}
/* If it was a directory, append a slash */
if (*workpos == '\\') {
*writepos++ = *workpos++;
}
*writepos = 0;
#else /* defined(PHP_WIN32) */
/* Look for .. */
if ((workpos[0] == '.') && (workpos[1] != 0)) {
if ((workpos[1] == '.') && ((workpos[2] == '/') || (workpos[2] == 0))) {
/* One directory back */
/* Set pointers to right position */
workpos++; /* move to second '.' */
workpos++; /* move to '/' */
/* Only apply .. if not in root */
if ((writepos-1) > path_construction) {
writepos--; /* move to '/' */
while(*--writepos != '/') ; /* skip until previous '/' */
}
} else {
if (workpos[1] == '/') {
/* Found a /./ skip it */
workpos++; /* move to '/' */
/* Avoid double / in the result */
writepos--;
} else {
/* No special case, the name just started with a . */
/* Append */
while((*workpos != '/') && (*workpos != 0)) {
*writepos++ = *workpos++;
}
}
}
} else {
/* No special case */
/* Append */
while((*workpos != '/') && (*workpos != 0)) {
*writepos++ = *workpos++;
}
}
#if HAVE_SYMLINK
/* We are going to use path_construction, so close it */
*writepos = 0;
/* Check the current location to see if it is a symlink */
if((linklength = readlink(path_construction, buf, MAXPATHLEN)) != -1) {
/* Check linkcount */
if (linkcount > MAXSYMLINKS) return NULL;
/* Count this symlink */
linkcount++;
/* Set end of buf */
buf[linklength] = 0;
/* Check for overflow */
if ((strlen(workpos) + strlen(buf) + 1) >= MAXPATHLEN) return NULL;
/* Remove the symlink-component wrom path_construction */
writepos--; /* move to '/' */
while(*--writepos != '/') ; /* skip until previous '/' */
*++writepos = 0; /* end of string after '/' */
/* If the symlink starts with a '/', empty path_construction */
if (*buf == '/') {
*path_construction = 0;
writepos = path_construction;
}
/* Insert symlink into path_copy */
strcat(buf, workpos);
strcpy(path_copy, buf);
workpos = path_copy;
}
#endif /* HAVE_SYMLINK */
/* If it was a directory, append a slash */
if (*workpos == '/') {
*writepos++ = *workpos++;
}
*writepos = 0;
#endif /* defined(PHP_WIN32) */
}
/* Check if the resolved path is a directory */
if (V_STAT(path_construction, &filestat) != 0) return NULL;
if (S_ISDIR(filestat.st_mode)) {
/* It's a directory, append a / if needed */
if (*(writepos-1) != '/') {
/* Check for overflow */
if ((strlen(workpos) + 2) >= MAXPATHLEN) return NULL;
*writepos++ = '/';
*writepos = 0;
}
}
strcpy(resolved_path, path_construction);
return resolved_path;
}
/*
* Local variables:
* tab-width: 4
* c-basic-offset: 4
* End:
*/
|
