1// Copyright 2016 The Fuchsia Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#include <fcntl.h> 6#include <limits.h> 7#include <stdint.h> 8#include <stdio.h> 9#include <stdlib.h> 10#include <sys/stat.h> 11#include <unistd.h> 12 13#include <zircon/syscalls.h> 14#include <unittest/unittest.h> 15 16#include "filesystems.h" 17 18constexpr char kName[] = "::my_file"; 19constexpr char kTestNameDotDot[] = "::foo/../bar/../my_file"; 20constexpr char kTestNameDot[] = "::././././my_file"; 21constexpr char kTestNameBothDots[] = "::foo//.././/./././my_file"; 22 23static bool terminator(char c) { return c == 0 || c == '/'; } 24 25static bool is_resolved(const char* path) { 26 // Check that there are no ".", "//", or ".." components. 27 // We assume there are no symlinks, since symlinks are not 28 // yet supported on Fuchsia. 29 while (true) { 30 if (path[0] == 0) { 31 return true; 32 } else if (path[0] == '.' && terminator(path[1])) { 33 return false; 34 } else if (path[0] == '/' && path[1] == '/') { 35 return false; 36 } else if (path[0] == '.' && path[1] == '.' && terminator(path[2])) { 37 return false; 38 } 39 if ((path = strchr(path, '/')) == NULL) { 40 return true; 41 } 42 path += 1; 43 } 44} 45 46bool test_realpath_absolute(void) { 47 BEGIN_TEST; 48 49 int fd = open(kName, O_RDWR | O_CREAT, 0644); 50 ASSERT_GT(fd, 0); 51 52 struct stat sb; 53 ASSERT_EQ(stat(kName, &sb), 0); 54 55 // Find the real path of the file (since, due to linker magic, we 56 // actually don't know it). 57 char buf[PATH_MAX]; 58 ASSERT_EQ(realpath(kName, buf), buf); 59 60 // Confirm that for (resolvable) cases of realpath, the name 61 // can be cleaned. 62 char buf2[PATH_MAX]; 63 ASSERT_EQ(realpath(kTestNameDotDot, buf2), buf2); 64 ASSERT_EQ(strcmp(buf, buf2), 0, "Name (with ..) did not resolve"); 65 ASSERT_TRUE(is_resolved(buf2)); 66 67 ASSERT_EQ(realpath(kTestNameDot, buf2), buf2); 68 ASSERT_EQ(strcmp(buf, buf2), 0, "Name (with .) did not resolve"); 69 ASSERT_TRUE(is_resolved(buf2)); 70 71 ASSERT_EQ(realpath(kTestNameBothDots, buf2), buf2); 72 ASSERT_EQ(strcmp(buf, buf2), 0, "Name (with . and ..) did not resolve"); 73 ASSERT_TRUE(is_resolved(buf2)); 74 75 // Clean up 76 ASSERT_EQ(close(fd), 0); 77 ASSERT_EQ(unlink(kName), 0); 78 END_TEST; 79} 80 81constexpr char kNameDir[] = "::my_dir"; 82constexpr char kNameFile[] = "::my_dir/my_file"; 83constexpr char kTestRelativeDotDot[] = "../my_dir/../my_dir/my_file"; 84constexpr char kTestRelativeDot[] = "./././my_file"; 85constexpr char kTestRelativeBothDots[] = "./..//my_dir/.././///././my_dir/./my_file"; 86 87bool test_realpath_relative(void) { 88 BEGIN_TEST; 89 90 ASSERT_EQ(mkdir(kNameDir, 0666), 0); 91 int fd = open(kNameFile, O_RDWR | O_CREAT, 0644); 92 ASSERT_GT(fd, 0); 93 close(fd); 94 95 struct stat sb; 96 ASSERT_EQ(stat(kNameFile, &sb), 0); 97 98 // Find the real path of the file (since, due to linker magic, we 99 // actually don't know it). 100 char buf[PATH_MAX]; 101 ASSERT_EQ(realpath(kNameFile, buf), buf); 102 103 char cwd[PATH_MAX]; 104 ASSERT_NONNULL(getcwd(cwd, sizeof(cwd))); 105 ASSERT_EQ(chdir(kNameDir), 0); 106 107 char buf2[PATH_MAX]; 108 ASSERT_EQ(realpath(kTestRelativeDotDot, buf2), buf2); 109 ASSERT_EQ(strcmp(buf, buf2), 0, "Name (with ..) did not resolve"); 110 ASSERT_TRUE(is_resolved(buf2)); 111 112 ASSERT_EQ(realpath(kTestRelativeDot, buf2), buf2); 113 ASSERT_EQ(strcmp(buf, buf2), 0, "Name (with .) did not resolve"); 114 ASSERT_TRUE(is_resolved(buf2)); 115 116 ASSERT_EQ(realpath(kTestRelativeBothDots, buf2), buf2); 117 ASSERT_EQ(strcmp(buf, buf2), 0, "Name (with . and ..) did not resolve"); 118 ASSERT_TRUE(is_resolved(buf2)); 119 120 // Test the longest possible path name 121 122 // Extract the current working directory name ("my_dir/my_file" - "my_file") 123 size_t cwd_len = strlen(buf) - strlen("my_file"); 124 char bufmax[PATH_MAX + 1]; 125 bufmax[0] = '.'; 126 size_t len = 1; 127 // When realpath completes, it should return a result of the 128 // form "CWD + '/' + "my_file". 129 // 130 // Ensure that our (uncanonicalized) path, including the CWD, 131 // can fit within PATH_MAX (but just barely). 132 while (len != PATH_MAX - cwd_len - strlen("my_file") - 1) { 133 bufmax[len++] = '/'; 134 } 135 memcpy(bufmax + len, "my_file", strlen("my_file")); 136 bufmax[len + strlen("my_file")] = 0; 137 ASSERT_EQ(strlen(bufmax), PATH_MAX - cwd_len - 1); 138 139 ASSERT_EQ(realpath(bufmax, buf2), buf2); 140 ASSERT_EQ(strcmp(buf, buf2), 0, "Name (longest path) did not resolve"); 141 ASSERT_TRUE(is_resolved(buf2)); 142 143 // Try a name that is too long (same as the last one, but just 144 // add a single additional "/"). 145 bufmax[len++] = '/'; 146 strcpy(bufmax + len, "my_file"); 147 ASSERT_NULL(realpath(bufmax, buf2)); 148 149 // Clean up 150 ASSERT_EQ(chdir(cwd), 0, "Could not return to original cwd"); 151 ASSERT_EQ(unlink(kNameFile), 0); 152 END_TEST; 153} 154 155RUN_FOR_ALL_FILESYSTEMS(realpath_tests, 156 RUN_TEST_MEDIUM(test_realpath_absolute) 157 RUN_TEST_MEDIUM(test_realpath_relative) 158) 159