mirrors/php-src
0
0
Fork 0
mirror of https://github.com/php/php-src.git synced 2024-11-25 02:44:58 +08:00
Code Issues Packages Projects Releases Wiki Activity
f432c05c3f
php-src/php3_realpath.c
Zeev Suraski aceaabceff PHP 4.0
1999-04-07 21:05:13 +00:00

291 lines
8.3 KiB
C
Raw Blame History

/*
+----------------------------------------------------------------------+
| PHP HTML Embedded Scripting Language Version 3.0 |
+----------------------------------------------------------------------+
| Copyright (c) 1997,1998 PHP Development Team (See Credits file) |
+----------------------------------------------------------------------+
| This program is free software; you can redistribute it and/or modify |
| it under the terms of one of the following licenses: |
| |
| A) the GNU General Public License as published by the Free Software |
| Foundation; either version 2 of the License, or (at your option) |
| any later version. |
| |
| B) the PHP License as published by the PHP Development Team and |
| included in the distribution in the file: LICENSE |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of both licenses referred to here. |
| If you did not, or have any questions about PHP licensing, please |
| contact core@php.net. |
+----------------------------------------------------------------------+
| Author: Sander Steffann (sander@steffann.nl) |
+----------------------------------------------------------------------+
*/
#ifdef THREAD_SAFE
#include "tls.h"
#endif
#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 *_php3_realpath(char *path, char resolved_path[]);
char *_php3_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 !(WIN32|WINNT)
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 */
#if WIN32|WINNT
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;
#if WIN32|WINNT
/* Find out where we start - Windows version */
if ((*workpos == '\\') || (*workpos == '/')) {
/* We start at the root of the current drive */
/* Get the current directory */
if (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 (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 (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 */
#if WIN32|WINNT
while(*workpos == '\\') workpos++;
#else
while(*workpos == '/') workpos++;
#endif
#if WIN32|WINNT
/* 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 /* WIN32|WINNT */
/* 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 /* WIN32|WINNT */
}
/* Check if the resolved path is a directory */
if (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:
*/
Reference in New Issue View Git Blame Copy Permalink