diff options
| -rw-r--r-- | src/dir.c | 185 |
1 files changed, 76 insertions, 109 deletions
@@ -14,7 +14,39 @@ #include <unistd.h> #if __linux__ -# include <sys/syscall.h> + +#include <sys/syscall.h> + +#if __has_feature(memory_sanitizer) +# include <sanitizer/msan_interface.h> +#endif + +/** Directory entry type for bfs_getdents() */ +typedef struct dirent64 sys_dirent; + +/** getdents() syscall wrapper. */ +static ssize_t bfs_getdents(int fd, void *buf, size_t size) { +#if __has_feature(memory_sanitizer) + __msan_allocated_memory(buf, size); +#endif + +#if __GLIBC__ && !__GLIBC_PREREQ(2, 30) + ssize_t ret = syscall(__NR_getdents64, fd, buf, size); +#else + ssize_t ret = getdents64(fd, buf, size); +#endif + +#if __has_feature(memory_sanitizer) + if (ret > 0) { + __msan_unpoison(buf, ret); + } +#endif + + return ret; +} + +#else // !__linux__ +typedef struct dirent sys_dirent; #endif enum bfs_type bfs_mode_to_type(mode_t mode) { @@ -65,23 +97,6 @@ enum bfs_type bfs_mode_to_type(mode_t mode) { } } -#if __linux__ -/** - * This is not defined in the kernel headers for some reason, callers have to - * define it themselves. - */ -struct linux_dirent64 { - ino64_t d_ino; - off64_t d_off; - unsigned short d_reclen; - unsigned char d_type; - char d_name[]; -}; - -// Make the whole allocation 64k -#define BUF_SIZE ((64 << 10) - 8) -#endif - struct bfs_dir { #if __linux__ int fd; @@ -93,6 +108,10 @@ struct bfs_dir { #endif }; +#if __linux__ +# define BUF_SIZE ((64 << 10) - sizeof(struct bfs_dir)) +#endif + struct bfs_dir *bfs_opendir(int at_fd, const char *at_path) { #if __linux__ struct bfs_dir *dir = malloc(sizeof(*dir) + BUF_SIZE); @@ -147,64 +166,44 @@ int bfs_dirfd(const struct bfs_dir *dir) { #endif } -/** Convert a dirent type to a bfs_type. */ -static enum bfs_type translate_type(int d_type) { - switch (d_type) { -#ifdef DT_BLK - case DT_BLK: - return BFS_BLK; -#endif -#ifdef DT_CHR - case DT_CHR: - return BFS_CHR; -#endif -#ifdef DT_DIR - case DT_DIR: - return BFS_DIR; -#endif -#ifdef DT_DOOR - case DT_DOOR: - return BFS_DOOR; -#endif -#ifdef DT_FIFO - case DT_FIFO: - return BFS_FIFO; -#endif -#ifdef DT_LNK - case DT_LNK: - return BFS_LNK; -#endif -#ifdef DT_PORT - case DT_PORT: - return BFS_PORT; -#endif -#ifdef DT_REG - case DT_REG: - return BFS_REG; -#endif -#ifdef DT_SOCK - case DT_SOCK: - return BFS_SOCK; -#endif -#ifdef DT_WHT - case DT_WHT: - return BFS_WHT; -#endif - } - +/** Convert de->d_type to a bfs_type, if it exists. */ +static enum bfs_type bfs_d_type(const sys_dirent *de) { +#ifdef DTTOIF + return bfs_mode_to_type(DTTOIF(de->d_type)); +#else return BFS_UNKNOWN; +#endif } -#if !__linux__ -/** Get the type from a struct dirent if it exists, and convert it. */ -static enum bfs_type dirent_type(const struct dirent *de) { -#if defined(_DIRENT_HAVE_D_TYPE) || defined(DT_UNKNOWN) - return translate_type(de->d_type); +/** Read a single directory entry. */ +static int bfs_getdent(struct bfs_dir *dir, const sys_dirent **de) { +#if __linux__ + char *buf = (char *)(dir + 1); + + if (dir->pos >= dir->size) { + ssize_t ret = bfs_getdents(dir->fd, buf, BUF_SIZE); + if (ret <= 0) { + return ret; + } + dir->pos = 0; + dir->size = ret; + } + + *de = (void *)(buf + dir->pos); + dir->pos += (*de)->d_reclen; + return 1; #else - return BFS_UNKNOWN; + errno = 0; + *de = readdir(dir->dir); + if (*de) { + return 1; + } else if (errno == 0) { + return 0; + } else { + return -1; + } #endif } -#endif /** Check if a name is . or .. */ static bool is_dot(const char *name) { @@ -213,54 +212,22 @@ static bool is_dot(const char *name) { int bfs_readdir(struct bfs_dir *dir, struct bfs_dirent *de) { while (true) { -#if __linux__ - char *buf = (char *)(dir + 1); - - if (dir->pos >= dir->size) { -#if __has_feature(memory_sanitizer) - // Make sure msan knows the buffer is initialized - memset(buf, 0, BUF_SIZE); -#endif - - ssize_t size = syscall(__NR_getdents64, dir->fd, buf, BUF_SIZE); - if (size <= 0) { - return size; - } - dir->pos = 0; - dir->size = size; + const sys_dirent *sysde; + int ret = bfs_getdent(dir, &sysde); + if (ret <= 0) { + return ret; } - const struct linux_dirent64 *lde = (void *)(buf + dir->pos); - dir->pos += lde->d_reclen; - - if (is_dot(lde->d_name)) { + if (is_dot(sysde->d_name)) { continue; } if (de) { - de->type = translate_type(lde->d_type); - de->name = lde->d_name; + de->type = bfs_d_type(sysde); + de->name = sysde->d_name; } return 1; -#else // !__linux__ - errno = 0; - dir->de = readdir(dir->dir); - if (dir->de) { - if (is_dot(dir->de->d_name)) { - continue; - } - if (de) { - de->type = dirent_type(dir->de); - de->name = dir->de->d_name; - } - return 1; - } else if (errno != 0) { - return -1; - } else { - return 0; - } -#endif // !__linux__ } } |