diff --git a/otautil/DirUtil.cpp b/otautil/DirUtil.cpp index ad344ded..fffc8221 100644 --- a/otautil/DirUtil.cpp +++ b/otautil/DirUtil.cpp @@ -16,147 +16,101 @@ #include "DirUtil.h" -#include -#include -#include -#include -#include -#include -#include #include -#include +#include +#include +#include +#include +#include #include #include #include -typedef enum { DMISSING, DDIR, DILLEGAL } DirStatus; +enum class DirStatus { DMISSING, DDIR, DILLEGAL }; -static DirStatus -getPathDirStatus(const char *path) -{ - struct stat st; - int err; - - err = stat(path, &st); - if (err == 0) { - /* Something's there; make sure it's a directory. - */ - if (S_ISDIR(st.st_mode)) { - return DDIR; - } - errno = ENOTDIR; - return DILLEGAL; - } else if (errno != ENOENT) { - /* Something went wrong, or something in the path - * is bad. Can't do anything in this situation. - */ - return DILLEGAL; +static DirStatus dir_status(const std::string& path) { + struct stat sb; + if (stat(path.c_str(), &sb) == 0) { + // Something's there; make sure it's a directory. + if (S_ISDIR(sb.st_mode)) { + return DirStatus::DDIR; } - return DMISSING; + errno = ENOTDIR; + return DirStatus::DILLEGAL; + } else if (errno != ENOENT) { + // Something went wrong, or something in the path is bad. Can't do anything in this situation. + return DirStatus::DILLEGAL; + } + return DirStatus::DMISSING; } -int -dirCreateHierarchy(const char *path, int mode, - const struct utimbuf *timestamp, bool stripFileName, - struct selabel_handle *sehnd) -{ - DirStatus ds; +int mkdir_recursively(const std::string& input_path, mode_t mode, bool strip_filename, + const selabel_handle* sehnd) { + // Check for an empty string before we bother making any syscalls. + if (input_path.empty()) { + errno = ENOENT; + return -1; + } - /* Check for an empty string before we bother - * making any syscalls. - */ - if (path[0] == '\0') { - errno = ENOENT; - return -1; - } - // Allocate a path that we can modify; stick a slash on - // the end to make things easier. - std::string cpath = path; - if (stripFileName) { - // Strip everything after the last slash. - size_t pos = cpath.rfind('/'); - if (pos == std::string::npos) { - errno = ENOENT; - return -1; - } - cpath.resize(pos + 1); - } else { - // Make sure that the path ends in a slash. - cpath.push_back('/'); + // Allocate a path that we can modify; stick a slash on the end to make things easier. + std::string path = input_path; + if (strip_filename) { + // Strip everything after the last slash. + size_t pos = path.rfind('/'); + if (pos == std::string::npos) { + errno = ENOENT; + return -1; } + path.resize(pos + 1); + } else { + // Make sure that the path ends in a slash. + path.push_back('/'); + } - /* See if it already exists. - */ - ds = getPathDirStatus(cpath.c_str()); - if (ds == DDIR) { - return 0; - } else if (ds == DILLEGAL) { - return -1; - } - - /* Walk up the path from the root and make each level. - * If a directory already exists, no big deal. - */ - const char *path_start = &cpath[0]; - char *p = &cpath[0]; - while (*p != '\0') { - /* Skip any slashes, watching out for the end of the string. - */ - while (*p != '\0' && *p == '/') { - p++; - } - if (*p == '\0') { - break; - } - - /* Find the end of the next path component. - * We know that we'll see a slash before the NUL, - * because we added it, above. - */ - while (*p != '/') { - p++; - } - *p = '\0'; - - /* Check this part of the path and make a new directory - * if necessary. - */ - ds = getPathDirStatus(path_start); - if (ds == DILLEGAL) { - /* Could happen if some other process/thread is - * messing with the filesystem. - */ - return -1; - } else if (ds == DMISSING) { - int err; - - char *secontext = NULL; - - if (sehnd) { - selabel_lookup(sehnd, &secontext, path_start, mode); - setfscreatecon(secontext); - } - - err = mkdir(path_start, mode); - - if (secontext) { - freecon(secontext); - setfscreatecon(NULL); - } - - if (err != 0) { - return -1; - } - if (timestamp != NULL && utime(path_start, timestamp)) { - return -1; - } - } - // else, this directory already exists. - - // Repair the path and continue. - *p = '/'; - } + // See if it already exists. + DirStatus ds = dir_status(path); + if (ds == DirStatus::DDIR) { return 0; + } else if (ds == DirStatus::DILLEGAL) { + return -1; + } + + // Walk up the path from the root and make each level. + size_t prev_end = 0; + while (prev_end < path.size()) { + size_t next_end = path.find('/', prev_end + 1); + if (next_end == std::string::npos) { + break; + } + std::string dir_path = path.substr(0, next_end); + // Check this part of the path and make a new directory if necessary. + switch (dir_status(dir_path)) { + case DirStatus::DILLEGAL: + // Could happen if some other process/thread is messing with the filesystem. + return -1; + case DirStatus::DMISSING: { + char* secontext = nullptr; + if (sehnd) { + selabel_lookup(const_cast(sehnd), &secontext, dir_path.c_str(), mode); + setfscreatecon(secontext); + } + int err = mkdir(dir_path.c_str(), mode); + if (secontext) { + freecon(secontext); + setfscreatecon(nullptr); + } + if (err != 0) { + return -1; + } + break; + } + default: + // Already exists. + break; + } + prev_end = next_end; + } + return 0; } diff --git a/otautil/DirUtil.h b/otautil/DirUtil.h index beecc108..85d6c16d 100644 --- a/otautil/DirUtil.h +++ b/otautil/DirUtil.h @@ -14,28 +14,26 @@ * limitations under the License. */ -#ifndef MINZIP_DIRUTIL_H_ -#define MINZIP_DIRUTIL_H_ +#ifndef OTAUTIL_DIRUTIL_H_ +#define OTAUTIL_DIRUTIL_H_ -#include +#include // mode_t + +#include struct selabel_handle; -/* Like "mkdir -p", try to guarantee that all directories - * specified in path are present, creating as many directories - * as necessary. The specified mode is passed to all mkdir - * calls; no modifications are made to umask. - * - * If stripFileName is set, everything after the final '/' - * is stripped before creating the directory hierarchy. - * - * If timestamp is non-NULL, new directories will be timestamped accordingly. - * - * Returns 0 on success; returns -1 (and sets errno) on failure - * (usually if some element of path is not a directory). - */ -int dirCreateHierarchy(const char *path, int mode, - const struct utimbuf *timestamp, bool stripFileName, - struct selabel_handle* sehnd); +// Like "mkdir -p", try to guarantee that all directories specified in path are present, creating as +// many directories as necessary. The specified mode is passed to all mkdir calls; no modifications +// are made to umask. +// +// If strip_filename is set, everything after the final '/' is stripped before creating the +// directory +// hierarchy. +// +// Returns 0 on success; returns -1 (and sets errno) on failure (usually if some element of path is +// not a directory). +int mkdir_recursively(const std::string& path, mode_t mode, bool strip_filename, + const struct selabel_handle* sehnd); -#endif // MINZIP_DIRUTIL_H_ +#endif // OTAUTIL_DIRUTIL_H_ diff --git a/recovery.cpp b/recovery.cpp index 8f3e9bde..233e5624 100644 --- a/recovery.cpp +++ b/recovery.cpp @@ -178,19 +178,19 @@ struct selabel_handle* sehandle; * 7b. the user reboots (pulling the battery, etc) into the main system */ -// open a given path, mounting partitions as necessary -FILE* fopen_path(const char *path, const char *mode) { - if (ensure_path_mounted(path) != 0) { - LOG(ERROR) << "Can't mount " << path; - return NULL; - } +// Open a given path, mounting partitions as necessary. +FILE* fopen_path(const char* path, const char* mode) { + if (ensure_path_mounted(path) != 0) { + LOG(ERROR) << "Can't mount " << path; + return nullptr; + } - // When writing, try to create the containing directory, if necessary. - // Use generous permissions, the system (init.rc) will reset them. - if (strchr("wa", mode[0])) dirCreateHierarchy(path, 0777, NULL, 1, sehandle); - - FILE *fp = fopen(path, mode); - return fp; + // When writing, try to create the containing directory, if necessary. Use generous permissions, + // the system (init.rc) will reset them. + if (strchr("wa", mode[0])) { + mkdir_recursively(path, 0777, true, sehandle); + } + return fopen(path, mode); } // close a file, log an error if the error indicator is set @@ -593,7 +593,7 @@ static bool erase_volume(const char* volume) { if (is_cache) { // Re-create the log dir and write back the log entries. if (ensure_path_mounted(CACHE_LOG_DIR) == 0 && - dirCreateHierarchy(CACHE_LOG_DIR, 0777, nullptr, false, sehandle) == 0) { + mkdir_recursively(CACHE_LOG_DIR, 0777, false, sehandle) == 0) { for (const auto& log : log_files) { if (!android::base::WriteStringToFile(log.data, log.name, log.sb.st_mode, log.sb.st_uid, log.sb.st_gid)) { diff --git a/tests/unit/dirutil_test.cpp b/tests/unit/dirutil_test.cpp index e62032c6..7f85d13e 100644 --- a/tests/unit/dirutil_test.cpp +++ b/tests/unit/dirutil_test.cpp @@ -26,23 +26,23 @@ TEST(DirUtilTest, create_invalid) { // Requesting to create an empty dir is invalid. - ASSERT_EQ(-1, dirCreateHierarchy("", 0755, nullptr, false, nullptr)); + ASSERT_EQ(-1, mkdir_recursively("", 0755, false, nullptr)); ASSERT_EQ(ENOENT, errno); // Requesting to strip the name with no slash present. - ASSERT_EQ(-1, dirCreateHierarchy("abc", 0755, nullptr, true, nullptr)); + ASSERT_EQ(-1, mkdir_recursively("abc", 0755, true, nullptr)); ASSERT_EQ(ENOENT, errno); // Creating a dir that already exists. TemporaryDir td; - ASSERT_EQ(0, dirCreateHierarchy(td.path, 0755, nullptr, false, nullptr)); + ASSERT_EQ(0, mkdir_recursively(td.path, 0755, false, nullptr)); // "///" is a valid dir. - ASSERT_EQ(0, dirCreateHierarchy("///", 0755, nullptr, false, nullptr)); + ASSERT_EQ(0, mkdir_recursively("///", 0755, false, nullptr)); // Request to create a dir, but a file with the same name already exists. TemporaryFile tf; - ASSERT_EQ(-1, dirCreateHierarchy(tf.path, 0755, nullptr, false, nullptr)); + ASSERT_EQ(-1, mkdir_recursively(tf.path, 0755, false, nullptr)); ASSERT_EQ(ENOTDIR, errno); } @@ -51,7 +51,7 @@ TEST(DirUtilTest, create_smoke) { std::string prefix(td.path); std::string path = prefix + "/a/b"; constexpr mode_t mode = 0755; - ASSERT_EQ(0, dirCreateHierarchy(path.c_str(), mode, nullptr, false, nullptr)); + ASSERT_EQ(0, mkdir_recursively(path, mode, false, nullptr)); // Verify. struct stat sb; @@ -69,7 +69,7 @@ TEST(DirUtilTest, create_strip_filename) { TemporaryDir td; std::string prefix(td.path); std::string path = prefix + "/a/b"; - ASSERT_EQ(0, dirCreateHierarchy(path.c_str(), 0755, nullptr, true, nullptr)); + ASSERT_EQ(0, mkdir_recursively(path, 0755, true, nullptr)); // Verify that "../a" exists but not "../a/b". struct stat sb; @@ -83,31 +83,21 @@ TEST(DirUtilTest, create_strip_filename) { ASSERT_EQ(0, rmdir((prefix + "/a").c_str())); } -TEST(DirUtilTest, create_mode_and_timestamp) { +TEST(DirUtilTest, create_mode) { TemporaryDir td; std::string prefix(td.path); std::string path = prefix + "/a/b"; - // Set the timestamp to 8/1/2008. - constexpr struct utimbuf timestamp = { 1217592000, 1217592000 }; constexpr mode_t mode = 0751; - ASSERT_EQ(0, dirCreateHierarchy(path.c_str(), mode, ×tamp, false, nullptr)); + ASSERT_EQ(0, mkdir_recursively(path, mode, false, nullptr)); - // Verify the mode and timestamp for "../a/b". + // Verify the mode for "../a/b". struct stat sb; ASSERT_EQ(0, stat(path.c_str(), &sb)) << strerror(errno); ASSERT_TRUE(S_ISDIR(sb.st_mode)); constexpr mode_t mask = S_IRWXU | S_IRWXG | S_IRWXO; ASSERT_EQ(mode, sb.st_mode & mask); - timespec time; - time.tv_sec = 1217592000; - time.tv_nsec = 0; - - ASSERT_EQ(time.tv_sec, static_cast(sb.st_atime)); - ASSERT_EQ(time.tv_sec, static_cast(sb.st_mtime)); - - // Verify the mode for "../a". Note that the timestamp for intermediate directories (e.g. "../a") - // may not be 'timestamp' according to the current implementation. + // Verify the mode for "../a". ASSERT_EQ(0, stat((prefix + "/a").c_str(), &sb)) << strerror(errno); ASSERT_TRUE(S_ISDIR(sb.st_mode)); ASSERT_EQ(mode, sb.st_mode & mask);