blob: b8e981e20fe7bd91b22386e73f8bd671d6dd4c94 [file] [log] [blame]
// Copyright 2016 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "unistd.h"
#include <dirent.h>
#include <fcntl.h>
#include <lib/fdio/fdio.h>
#include <lib/fdio/io.h>
#include <lib/fdio/namespace.h>
#include <lib/fdio/private.h>
#include <lib/fdio/unsafe.h>
#include <lib/fdio/vfs.h>
#include <poll.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/select.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/statfs.h>
#include <sys/statvfs.h>
#include <sys/uio.h>
#include <threads.h>
#include <utime.h>
#include <zircon/compiler.h>
#include <zircon/device/vfs.h>
#include <zircon/process.h>
#include <zircon/processargs.h>
#include <zircon/syscalls.h>
#include <cstdarg>
#include <fbl/auto_lock.h>
#include "private.h"
namespace fio = ::llcpp::fuchsia::io;
static_assert(IOFLAG_CLOEXEC == FD_CLOEXEC, "Unexpected fdio flags value");
// Helper functions
// Open |path| from the |dirfd| directory, enforcing the POSIX EISDIR error condition. Specifically,
// ZX_ERR_NOT_FILE will be returned when opening a directory with write access/O_CREAT.
static zx_status_t __fdio_open_at(fdio_t** io, int dirfd, const char* path, int flags,
uint32_t mode);
// Open |path| from the |dirfd| directory, but allow creating directories/opening them with
// write access. Note that this differs from POSIX behavior.
static zx_status_t __fdio_open_at_ignore_eisdir(fdio_t** io, int dirfd, const char* path, int flags,
uint32_t mode);
// Open |path| from the current working directory, respecting EISDIR.
static zx_status_t __fdio_open(fdio_t** io, const char* path, int flags, uint32_t mode);
// non-thread-safe emulation of unistd io functions
// using the fdio transports
// Constexpr function to compute the initialized value for __fdio_globbal_state at compile time.
// If this is not constexpr, then initialization would happen after __libc_extensions_init,
// wiping the fd table *after* it has been fill in with valid entries.
// (musl invokes "__libc_start_init" after "__libc_extensions_init")
static constexpr fdio_state_t initialize_fdio_state() {
fdio_state_t state = {};
state.lock = MTX_INIT;
state.cwd_lock = MTX_INIT;
state.cwd_path[0] = '/';
state.cwd_path[1] = '\0';
return state;
}
fdio_state_t __fdio_global_state = initialize_fdio_state();
static bool fdio_is_reserved_or_null(fdio_t* io) {
if (io == NULL || io == fdio_get_reserved_io()) {
return true;
}
return false;
}
int fdio_reserve_fd(int starting_fd) {
if ((starting_fd < 0) || (starting_fd >= FDIO_MAX_FD)) {
errno = EINVAL;
return -1;
}
fbl::AutoLock lock(&fdio_lock);
for (int fd = starting_fd; fd < FDIO_MAX_FD; fd++) {
if (fdio_fdtab[fd] == NULL) {
fdio_fdtab[fd] = fdio_get_reserved_io();
return fd;
}
}
errno = EMFILE;
return -1;
}
int fdio_assign_reserved(int fd, fdio_t* io) {
fbl::AutoLock lock(&fdio_lock);
fdio_t* res = fdio_fdtab[fd];
if (res != fdio_get_reserved_io()) {
errno = EINVAL;
return -1;
}
fdio_dupcount_acquire(io);
fdio_fdtab[fd] = io;
return fd;
}
int fdio_release_reserved(int fd) {
if ((fd < 0) || (fd >= FDIO_MAX_FD)) {
errno = EINVAL;
return -1;
}
fbl::AutoLock lock(&fdio_lock);
fdio_t* res = fdio_fdtab[fd];
if (res != fdio_get_reserved_io()) {
errno = EINVAL;
return -1;
}
fdio_fdtab[fd] = NULL;
return fd;
}
// Attaches an fdio to an fdtab slot.
// The fdio must have been upref'd on behalf of the
// fdtab prior to binding.
__EXPORT
int fdio_bind_to_fd(fdio_t* io, int fd, int starting_fd) {
fdio_t* io_to_close = NULL;
{
fbl::AutoLock lock(&fdio_lock);
if (fd < 0) {
// If we are not given an |fd|, the |starting_fd| must be non-negative.
if (starting_fd < 0) {
errno = EINVAL;
return -1;
}
// A negative fd implies that any free fd value can be used
// TODO: bitmap, ffs, etc
for (fd = starting_fd; fd < FDIO_MAX_FD; fd++) {
if (fdio_fdtab[fd] == NULL) {
goto free_fd_found;
}
}
errno = EMFILE;
return -1;
} else if (fd >= FDIO_MAX_FD) {
errno = EINVAL;
return -1;
}
io_to_close = fdio_fdtab[fd];
if (io_to_close) {
fdio_dupcount_release(io_to_close);
if (fdio_get_dupcount(io_to_close) > 0) {
// still alive in another fdtab slot
fdio_release(io_to_close);
io_to_close = NULL;
}
}
free_fd_found:
fdio_dupcount_acquire(io);
fdio_fdtab[fd] = io;
}
if (io_to_close) {
fdio_get_ops(io_to_close)->close(io_to_close);
fdio_release(io_to_close);
}
return fd;
}
// If a fdio_t exists for this fd and it has not been dup'd
// and is not in active use (an io operation underway, etc),
// detach it from the fdtab and return it with a single
// refcount.
__EXPORT
zx_status_t fdio_unbind_from_fd(int fd, fdio_t** out) {
fbl::AutoLock lock(&fdio_lock);
if (fd >= FDIO_MAX_FD) {
return ZX_ERR_INVALID_ARGS;
}
fdio_t* io = fdio_fdtab[fd];
if (fdio_is_reserved_or_null(io)) {
return ZX_ERR_INVALID_ARGS;
}
if (fdio_get_dupcount(io) > 1) {
return ZX_ERR_UNAVAILABLE;
}
if (!fdio_is_last_reference(io)) {
return ZX_ERR_UNAVAILABLE;
}
fdio_dupcount_release(io);
fdio_fdtab[fd] = NULL;
*out = io;
return ZX_OK;
}
__EXPORT
fdio_t* fdio_unsafe_fd_to_io(int fd) {
if ((fd < 0) || (fd >= FDIO_MAX_FD)) {
return NULL;
}
fdio_t* io = NULL;
fbl::AutoLock lock(&fdio_lock);
io = fdio_fdtab[fd];
if (fdio_is_reserved_or_null(io)) {
// Never hand back the reserved io as it does not have an ops table.
io = NULL;
} else {
fdio_acquire(io);
}
return io;
}
zx_status_t fdio_close(fdio_t* io) { return fdio_get_ops(io)->close(io); }
// Verify the O_* flags which align with ZXIO_FS_*.
static_assert(O_PATH == ZX_FS_FLAG_VNODE_REF_ONLY, "Open Flag mismatch");
static_assert(O_ADMIN == ZX_FS_RIGHT_ADMIN, "Open Flag mismatch");
static_assert(O_CREAT == ZX_FS_FLAG_CREATE, "Open Flag mismatch");
static_assert(O_EXCL == ZX_FS_FLAG_EXCLUSIVE, "Open Flag mismatch");
static_assert(O_TRUNC == ZX_FS_FLAG_TRUNCATE, "Open Flag mismatch");
static_assert(O_DIRECTORY == ZX_FS_FLAG_DIRECTORY, "Open Flag mismatch");
static_assert(O_APPEND == ZX_FS_FLAG_APPEND, "Open Flag mismatch");
static_assert(O_NOREMOTE == ZX_FS_FLAG_NOREMOTE, "Open Flag mismatch");
// The mask of "1:1" flags which match between both open flag representations.
#define ZXIO_FS_MASK \
(O_PATH | O_ADMIN | O_CREAT | O_EXCL | O_TRUNC | O_DIRECTORY | O_APPEND | O_NOREMOTE)
#define ZXIO_FS_FLAGS \
(ZXIO_FS_MASK | ZX_FS_FLAG_POSIX | ZX_FS_FLAG_NOT_DIRECTORY | ZX_FS_FLAG_CLONE_SAME_RIGHTS)
// Verify that the remaining O_* flags don't overlap with the ZXIO_FS flags.
static_assert(!(O_RDONLY & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
static_assert(!(O_WRONLY & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
static_assert(!(O_RDWR & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
static_assert(!(O_NONBLOCK & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
static_assert(!(O_DSYNC & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
static_assert(!(O_SYNC & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
static_assert(!(O_RSYNC & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
static_assert(!(O_NOFOLLOW & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
static_assert(!(O_CLOEXEC & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
static_assert(!(O_NOCTTY & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
static_assert(!(O_ASYNC & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
static_assert(!(O_DIRECT & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
static_assert(!(O_LARGEFILE & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
static_assert(!(O_NOATIME & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
static_assert(!(O_TMPFILE & ZXIO_FS_FLAGS), "Unexpected collision with ZXIO_FS_FLAGS");
#define ZX_FS_FLAGS_ALLOWED_WITH_O_PATH \
(ZX_FS_FLAG_VNODE_REF_ONLY | ZX_FS_FLAG_DIRECTORY | ZX_FS_FLAG_NOT_DIRECTORY | \
ZX_FS_FLAG_DESCRIBE)
static uint32_t fdio_flags_to_zxio(uint32_t flags) {
uint32_t rights = 0;
switch (flags & O_ACCMODE) {
case O_RDONLY:
rights |= ZX_FS_RIGHT_READABLE;
break;
case O_WRONLY:
rights |= ZX_FS_RIGHT_WRITABLE;
break;
case O_RDWR:
rights |= ZX_FS_RIGHT_READABLE | ZX_FS_RIGHT_WRITABLE;
break;
}
uint32_t result = rights | ZX_FS_FLAG_DESCRIBE | (flags & ZXIO_FS_MASK);
if (!(result & ZX_FS_FLAG_VNODE_REF_ONLY)) {
result |= ZX_FS_FLAG_POSIX;
}
return result;
}
static uint32_t zxio_flags_to_fdio(uint32_t flags) {
uint32_t result = 0;
if ((flags & (ZX_FS_RIGHT_READABLE | ZX_FS_RIGHT_WRITABLE)) ==
(ZX_FS_RIGHT_READABLE | ZX_FS_RIGHT_WRITABLE)) {
result |= O_RDWR;
} else if (flags & ZX_FS_RIGHT_WRITABLE) {
result |= O_WRONLY;
} else {
result |= O_RDONLY;
}
result |= (flags & ZXIO_FS_MASK);
return result;
}
// Possibly return an owned fdio_t corresponding to either the root,
// the cwd, or, for the ...at variants, dirfd. In the absolute path
// case, *path is also adjusted.
static fdio_t* fdio_iodir(const char** path, int dirfd) {
fdio_t* iodir = NULL;
fbl::AutoLock lock(&fdio_lock);
if (*path[0] == '/') {
iodir = fdio_root_handle;
// Since we are sending a request to the root handle, the
// rest of the path should be canonicalized as a relative
// path (relative to this root handle).
while (*path[0] == '/') {
(*path)++;
if (*path[0] == 0) {
*path = ".";
}
}
} else if (dirfd == AT_FDCWD) {
iodir = fdio_cwd_handle;
} else if ((dirfd >= 0) && (dirfd < FDIO_MAX_FD)) {
iodir = fdio_fdtab[dirfd];
}
if (iodir != NULL) {
fdio_acquire(iodir);
}
return iodir;
}
#define IS_SEPARATOR(c) ((c) == '/' || (c) == 0)
// Checks that if we increment this index forward, we'll
// still have enough space for a null terminator within
// PATH_MAX bytes.
#define CHECK_CAN_INCREMENT(i) \
if (unlikely((i) + 1 >= PATH_MAX)) { \
return ZX_ERR_BAD_PATH; \
}
// Cleans an input path, transforming it to out, according to the
// rules defined by "Lexical File Names in Plan 9 or Getting Dot-Dot Right",
// accessible at: https://9p.io/sys/doc/lexnames.html
//
// Code heavily inspired by Go's filepath.Clean function, from:
// https://golang.org/src/path/filepath/path.go
//
// out is expected to be PATH_MAX bytes long.
// Sets is_dir to 'true' if the path is a directory, and 'false' otherwise.
__EXPORT
zx_status_t __fdio_cleanpath(const char* in, char* out, size_t* outlen, bool* is_dir) {
if (in[0] == 0) {
strcpy(out, ".");
*outlen = 1;
*is_dir = true;
return ZX_OK;
}
bool rooted = (in[0] == '/');
size_t in_index = 0; // Index of the next byte to read
size_t out_index = 0; // Index of the next byte to write
if (rooted) {
out[out_index++] = '/';
in_index++;
*is_dir = true;
}
size_t dotdot = out_index; // The output index at which '..' cannot be cleaned further.
while (in[in_index] != 0) {
*is_dir = true;
if (in[in_index] == '/') {
// 1. Reduce multiple slashes to a single slash
CHECK_CAN_INCREMENT(in_index);
in_index++;
} else if (in[in_index] == '.' && IS_SEPARATOR(in[in_index + 1])) {
// 2. Eliminate . path name elements (the current directory)
CHECK_CAN_INCREMENT(in_index);
in_index++;
} else if (in[in_index] == '.' && in[in_index + 1] == '.' && IS_SEPARATOR(in[in_index + 2])) {
CHECK_CAN_INCREMENT(in_index + 1);
in_index += 2;
if (out_index > dotdot) {
// 3. Eliminate .. path elements (the parent directory) and the element that
// precedes them.
out_index--;
while (out_index > dotdot && out[out_index] != '/') {
out_index--;
}
} else if (rooted) {
// 4. Eliminate .. elements that begin a rooted path, that is, replace /.. by / at
// the beginning of a path.
continue;
} else if (!rooted) {
if (out_index > 0) {
out[out_index++] = '/';
}
// 5. Leave intact .. elements that begin a non-rooted path.
out[out_index++] = '.';
out[out_index++] = '.';
dotdot = out_index;
}
} else {
*is_dir = false;
if ((rooted && out_index != 1) || (!rooted && out_index != 0)) {
// Add '/' before normal path component, for non-root components.
out[out_index++] = '/';
}
while (!IS_SEPARATOR(in[in_index])) {
CHECK_CAN_INCREMENT(in_index);
out[out_index++] = in[in_index++];
}
}
}
if (out_index == 0) {
strcpy(out, ".");
*outlen = 1;
*is_dir = true;
return ZX_OK;
}
// Append null character
*outlen = out_index;
out[out_index++] = 0;
return ZX_OK;
}
static zx_status_t __fdio_open_at_impl(fdio_t** io, int dirfd, const char* path, int flags,
uint32_t mode, bool enforce_eisdir) {
if (path == NULL) {
return ZX_ERR_INVALID_ARGS;
}
if (path[0] == '\0') {
return ZX_ERR_NOT_FOUND;
}
fdio_t* iodir = fdio_iodir(&path, dirfd);
if (iodir == NULL) {
return ZX_ERR_BAD_HANDLE;
}
char clean[PATH_MAX];
size_t outlen;
bool has_ending_slash;
zx_status_t status = __fdio_cleanpath(path, clean, &outlen, &has_ending_slash);
if (status != ZX_OK) {
fdio_release(iodir);
return status;
}
// Emulate EISDIR behavior from
// http://pubs.opengroup.org/onlinepubs/9699919799/functions/open.html
bool flags_incompatible_with_directory =
((flags & ~O_PATH & O_ACCMODE) != O_RDONLY) || (flags & O_CREAT);
if (enforce_eisdir && has_ending_slash && flags_incompatible_with_directory) {
fdio_release(iodir);
return ZX_ERR_NOT_FILE;
}
flags |= (has_ending_slash ? O_DIRECTORY : 0);
uint32_t zx_flags = fdio_flags_to_zxio((uint32_t)flags);
if (!(zx_flags & ZX_FS_FLAG_DIRECTORY)) {
// At this point we're not sure if the path refers to a directory.
// To emulate EISDIR behavior, if the flags are not compatible with directory,
// use this flag to instruct open to error if the path turns out to be a directory.
// Otherwise, opening a directory with O_RDWR will incorrectly succeed.
if (enforce_eisdir && flags_incompatible_with_directory) {
zx_flags |= ZX_FS_FLAG_NOT_DIRECTORY;
}
}
if (zx_flags & ZX_FS_FLAG_VNODE_REF_ONLY) {
zx_flags &= ZX_FS_FLAGS_ALLOWED_WITH_O_PATH;
}
status = fdio_get_ops(iodir)->open(iodir, clean, zx_flags, mode, io);
fdio_release(iodir);
return status;
}
static zx_status_t __fdio_open_at(fdio_t** io, int dirfd, const char* path, int flags,
uint32_t mode) {
return __fdio_open_at_impl(io, dirfd, path, flags, mode, true);
}
static zx_status_t __fdio_open_at_ignore_eisdir(fdio_t** io, int dirfd, const char* path, int flags,
uint32_t mode) {
return __fdio_open_at_impl(io, dirfd, path, flags, mode, false);
}
static zx_status_t __fdio_open(fdio_t** io, const char* path, int flags, uint32_t mode) {
return __fdio_open_at(io, AT_FDCWD, path, flags, mode);
}
static void update_cwd_path(const char* path) {
if (path[0] == '/') {
// it's "absolute", but we'll still parse it as relative (from /)
// so that we normalize the path (resolving, ., .., //, etc)
fdio_cwd_path[0] = '/';
fdio_cwd_path[1] = 0;
path++;
}
size_t seglen;
const char* next;
for (; path[0]; path = next) {
next = strchr(path, '/');
if (next == NULL) {
seglen = strlen(path);
next = path + seglen;
} else {
seglen = next - path;
next++;
}
if (seglen == 0) {
// empty segment, skip
continue;
}
if ((seglen == 1) && (path[0] == '.')) {
// no-change segment, skip
continue;
}
if ((seglen == 2) && (path[0] == '.') && (path[1] == '.')) {
// parent directory, remove the trailing path segment from cwd_path
char* x = strrchr(fdio_cwd_path, '/');
if (x == NULL) {
// shouldn't ever happen
goto wat;
}
// remove the current trailing path segment from cwd
if (x == fdio_cwd_path) {
// but never remove the first /
fdio_cwd_path[1] = 0;
} else {
x[0] = 0;
}
continue;
}
// regular path segment, append to cwd_path
size_t len = strlen(fdio_cwd_path);
if ((len + seglen + 2) >= PATH_MAX) {
// doesn't fit, shouldn't happen, but...
goto wat;
}
if (len != 1) {
// if len is 1, path is "/", so don't append a '/'
fdio_cwd_path[len++] = '/';
}
memcpy(fdio_cwd_path + len, path, seglen);
fdio_cwd_path[len + seglen] = 0;
}
return;
wat:
strcpy(fdio_cwd_path, "(unknown)");
}
// Opens the directory containing path
//
// Returns the non-directory portion of the path in 'out', which
// must be a buffer that can fit [NAME_MAX + 1] characters.
static zx_status_t __fdio_opendir_containing_at(fdio_t** io, int dirfd, const char* path,
char* out) {
if (path == NULL) {
return ZX_ERR_INVALID_ARGS;
}
fdio_t* iodir = fdio_iodir(&path, dirfd);
if (iodir == NULL) {
return ZX_ERR_BAD_HANDLE;
}
char clean[PATH_MAX];
size_t pathlen;
bool is_dir;
zx_status_t status = __fdio_cleanpath(path, clean, &pathlen, &is_dir);
if (status != ZX_OK) {
fdio_release(iodir);
return status;
}
// Find the last '/'; copy everything after it.
size_t i = 0;
for (i = pathlen - 1; i > 0; i--) {
if (clean[i] == '/') {
clean[i] = 0;
i++;
break;
}
}
// clean[i] is now the start of the name
size_t namelen = pathlen - i;
if (namelen + (is_dir ? 1 : 0) > NAME_MAX) {
fdio_release(iodir);
return ZX_ERR_BAD_PATH;
}
// Copy the trailing 'name' to out.
memcpy(out, clean + i, namelen);
if (is_dir) {
// TODO(fxb/37408): Propagate whether path is directory without using
// trailing backslash to simplify server-side path parsing.
// This might require refactoring trailing backslash checks out of
// lower filesystem layers and associated FIDL APIs.
out[namelen++] = '/';
}
out[namelen] = 0;
if (i == 0 && clean[i] != '/') {
clean[0] = '.';
clean[1] = 0;
}
zx_status_t r =
fdio_get_ops(iodir)->open(iodir, clean, fdio_flags_to_zxio(O_RDONLY | O_DIRECTORY), 0, io);
fdio_release(iodir);
return r;
}
// 'name' must be a user-provided buffer, at least NAME_MAX + 1 bytes long.
static zx_status_t __fdio_opendir_containing(fdio_t** io, const char* path, char* name) {
return __fdio_opendir_containing_at(io, AT_FDCWD, path, name);
}
// hook into libc process startup
// this is called prior to main to set up the fdio world
// and thus does not use the fdio_lock
//
// extern "C" is required here, since the corresponding declaration is in an internal musl header:
// zircon/third_party/ulib/musl/src/internal/libc.h
extern "C" __EXPORT void __libc_extensions_init(uint32_t handle_count, zx_handle_t handle[],
uint32_t handle_info[], uint32_t name_count,
char** names) {
zx_status_t status = fdio_ns_create(&fdio_root_ns);
ZX_ASSERT_MSG(status == ZX_OK, "Failed to create root namespace");
int stdio_fd = -1;
// extract handles we care about
for (uint32_t n = 0; n < handle_count; n++) {
unsigned arg = PA_HND_ARG(handle_info[n]);
zx_handle_t h = handle[n];
// precalculate the fd from |arg|, for FDIO cases to use.
unsigned arg_fd = arg & (~FDIO_FLAG_USE_FOR_STDIO);
switch (PA_HND_TYPE(handle_info[n])) {
case PA_FD: {
fdio_t* io = NULL;
status = fdio_create(h, &io);
if (status != ZX_OK) {
zx_handle_close(h);
continue;
}
fdio_fdtab[arg_fd] = io;
fdio_dupcount_acquire(fdio_fdtab[arg_fd]);
break;
}
case PA_NS_DIR:
// we always continue here to not steal the
// handles from higher level code that may
// also need access to the namespace
if (arg >= name_count) {
continue;
}
fdio_ns_bind(fdio_root_ns, names[arg], h);
continue;
default:
// unknown handle, leave it alone
continue;
}
handle[n] = 0;
handle_info[n] = 0;
// If we reach here then the handle is a PA_FD type (a file descriptor),
// so check for a bit flag indicating that it should be duped
// into 0/1/2 to become all of stdin/out/err
if ((arg & FDIO_FLAG_USE_FOR_STDIO) && (arg_fd < FDIO_MAX_FD)) {
stdio_fd = arg_fd;
}
}
const char* cwd = getenv("PWD");
cwd = (cwd == NULL) ? "/" : cwd;
update_cwd_path(cwd);
fdio_t* use_for_stdio = (stdio_fd >= 0) ? fdio_fdtab[stdio_fd] : NULL;
// configure stdin/out/err if not init'd
for (uint32_t n = 0; n < 3; n++) {
if (fdio_fdtab[n] == NULL) {
if (use_for_stdio) {
fdio_acquire(use_for_stdio);
fdio_fdtab[n] = use_for_stdio;
} else {
fdio_fdtab[n] = fdio_null_create();
}
fdio_dupcount_acquire(fdio_fdtab[n]);
}
}
ZX_ASSERT(!fdio_root_handle);
fdio_root_handle = fdio_ns_open_root(fdio_root_ns);
if (fdio_root_handle) {
__fdio_open(&fdio_cwd_handle, fdio_cwd_path, O_RDONLY | O_DIRECTORY, 0);
} else {
// placeholder null handle
fdio_root_handle = fdio_null_create();
}
if (fdio_cwd_handle == NULL) {
fdio_cwd_handle = fdio_null_create();
}
}
// Clean up during process teardown. This runs after atexit hooks in
// libc. It continues to hold the fdio lock until process exit, to
// prevent other threads from racing on file descriptors.
//
// extern "C" is required here, since the corresponding declaration is in an internal musl header:
// zircon/third_party/ulib/musl/src/internal/libc.h
extern "C" __EXPORT void __libc_extensions_fini(void) __TA_ACQUIRE(&fdio_lock) {
mtx_lock(&fdio_lock);
for (int fd = 0; fd < FDIO_MAX_FD; fd++) {
fdio_t* io = fdio_fdtab[fd];
if (!fdio_is_reserved_or_null(io)) {
fdio_fdtab[fd] = NULL;
fdio_dupcount_release(io);
if (fdio_get_dupcount(io) == 0) {
fdio_get_ops(io)->close(io);
fdio_release(io);
}
}
}
}
__EXPORT
zx_status_t fdio_ns_get_installed(fdio_ns_t** ns) {
zx_status_t status = ZX_OK;
fbl::AutoLock lock(&fdio_lock);
if (fdio_root_ns == NULL) {
status = ZX_ERR_NOT_FOUND;
} else {
*ns = fdio_root_ns;
}
return status;
}
zx_status_t fdio_wait(fdio_t* io, uint32_t events, zx::time deadline, uint32_t* out_pending) {
zx_handle_t h = ZX_HANDLE_INVALID;
zx_signals_t signals = 0;
fdio_get_ops(io)->wait_begin(io, events, &h, &signals);
if (h == ZX_HANDLE_INVALID)
// Wait operation is not applicable to the handle.
return ZX_ERR_INVALID_ARGS;
zx_signals_t pending;
zx_status_t status = zx_object_wait_one(h, signals, deadline.get(), &pending);
if (status == ZX_OK || status == ZX_ERR_TIMED_OUT) {
fdio_get_ops(io)->wait_end(io, pending, &events);
if (out_pending != nullptr) {
*out_pending = events;
}
}
return status;
}
__EXPORT
zx_status_t fdio_wait_fd(int fd, uint32_t events, uint32_t* out_pending, zx_time_t deadline) {
fdio_t* io = fd_to_io(fd);
if (io == NULL)
return ZX_ERR_BAD_HANDLE;
zx_status_t status = fdio_wait(io, events, zx::time(deadline), out_pending);
fdio_release(io);
return status;
}
static zx_status_t fdio_stat(fdio_t* io, struct stat* s) {
zxio_node_attr_t attr;
zx_status_t status = fdio_get_ops(io)->get_attr(io, &attr);
if (status != ZX_OK) {
return status;
}
memset(s, 0, sizeof(struct stat));
s->st_mode = fdio_get_ops(io)->convert_to_posix_mode(io, attr.protocols, attr.abilities);
s->st_ino = attr.has.id ? attr.id : fio::INO_UNKNOWN;
s->st_size = attr.content_size;
s->st_blksize = VNATTR_BLKSIZE;
s->st_blocks = attr.storage_size / VNATTR_BLKSIZE;
s->st_nlink = attr.link_count;
s->st_ctim.tv_sec = attr.creation_time / ZX_SEC(1);
s->st_ctim.tv_nsec = attr.creation_time % ZX_SEC(1);
s->st_mtim.tv_sec = attr.modification_time / ZX_SEC(1);
s->st_mtim.tv_nsec = attr.modification_time % ZX_SEC(1);
return ZX_OK;
}
// TODO(ZX-974): determine complete correct mapping
int fdio_status_to_errno(zx_status_t status) {
switch (status) {
case ZX_ERR_NOT_FOUND:
return ENOENT;
case ZX_ERR_NO_MEMORY:
return ENOMEM;
case ZX_ERR_INVALID_ARGS:
return EINVAL;
case ZX_ERR_BUFFER_TOO_SMALL:
return EINVAL;
case ZX_ERR_TIMED_OUT:
return ETIMEDOUT;
case ZX_ERR_UNAVAILABLE:
return EBUSY;
case ZX_ERR_ALREADY_EXISTS:
return EEXIST;
case ZX_ERR_PEER_CLOSED:
return EPIPE;
case ZX_ERR_BAD_STATE:
return EPIPE;
case ZX_ERR_BAD_PATH:
return ENAMETOOLONG;
case ZX_ERR_IO:
return EIO;
case ZX_ERR_NOT_FILE:
return EISDIR;
case ZX_ERR_NOT_DIR:
return ENOTDIR;
case ZX_ERR_NOT_SUPPORTED:
return ENOTSUP;
case ZX_ERR_WRONG_TYPE:
return ENOTSUP;
case ZX_ERR_OUT_OF_RANGE:
return EINVAL;
case ZX_ERR_NO_RESOURCES:
return ENOMEM;
case ZX_ERR_BAD_HANDLE:
return EBADF;
case ZX_ERR_ACCESS_DENIED:
return EACCES;
case ZX_ERR_SHOULD_WAIT:
return EAGAIN;
case ZX_ERR_FILE_BIG:
return EFBIG;
case ZX_ERR_NO_SPACE:
return ENOSPC;
case ZX_ERR_NOT_EMPTY:
return ENOTEMPTY;
case ZX_ERR_IO_REFUSED:
return ECONNREFUSED;
case ZX_ERR_IO_INVALID:
return EIO;
case ZX_ERR_CANCELED:
return EBADF;
case ZX_ERR_PROTOCOL_NOT_SUPPORTED:
return EPROTONOSUPPORT;
case ZX_ERR_ADDRESS_UNREACHABLE:
return ENETUNREACH;
case ZX_ERR_ADDRESS_IN_USE:
return EADDRINUSE;
case ZX_ERR_NOT_CONNECTED:
return ENOTCONN;
case ZX_ERR_CONNECTION_REFUSED:
return ECONNREFUSED;
case ZX_ERR_CONNECTION_RESET:
return ECONNRESET;
case ZX_ERR_CONNECTION_ABORTED:
return ECONNABORTED;
// No specific translation, so return a generic value.
default:
return EIO;
}
}
// The functions from here on provide implementations of fd and path
// centric posix-y io operations.
// extern "C" is required here, since the corresponding declaration is in an internal musl header:
// zircon/third_party/ulib/musl/src/internal/stdio_impl.h
extern "C" __EXPORT zx_status_t _mmap_file(size_t offset, size_t len, zx_vm_option_t zx_options,
int flags, int fd, off_t fd_off, uintptr_t* out) {
fdio_t* io;
if ((io = fd_to_io(fd)) == NULL) {
return ZX_ERR_BAD_HANDLE;
}
int vflags = zx_options | (flags & MAP_PRIVATE ? fio::VMO_FLAG_PRIVATE : 0);
zx::vmo vmo;
zx_status_t r = fdio_get_ops(io)->get_vmo(io, vflags, &vmo);
fdio_release(io);
// On POSIX, performing mmap on an fd which does not support it returns an access denied error.
if (r == ZX_ERR_NOT_SUPPORTED) {
return ZX_ERR_ACCESS_DENIED;
}
if (r < 0) {
return r;
}
uintptr_t ptr = 0;
zx_options |= ZX_VM_ALLOW_FAULTS;
r = zx_vmar_map(zx_vmar_root_self(), zx_options, offset, vmo.get(), fd_off, len, &ptr);
// TODO: map this as shared if we ever implement forking
if (r < 0) {
return r;
}
*out = ptr;
return ZX_OK;
}
__EXPORT
int unlinkat(int dirfd, const char* path, int flags) {
char name[NAME_MAX + 1];
fdio_t* io;
zx_status_t r;
if ((r = __fdio_opendir_containing_at(&io, dirfd, path, name)) < 0) {
return ERROR(r);
}
r = fdio_get_ops(io)->unlink(io, name, strlen(name));
fdio_get_ops(io)->close(io);
fdio_release(io);
return STATUS(r);
}
__EXPORT
ssize_t readv(int fd, const struct iovec* iov, int iovcnt) {
struct msghdr msg = {};
msg.msg_iov = const_cast<struct iovec*>(iov);
msg.msg_iovlen = iovcnt;
return recvmsg(fd, &msg, 0);
}
__EXPORT
ssize_t writev(int fd, const struct iovec* iov, int iovcnt) {
struct msghdr msg = {};
msg.msg_iov = const_cast<struct iovec*>(iov);
msg.msg_iovlen = iovcnt;
return sendmsg(fd, &msg, 0);
}
__EXPORT
ssize_t preadv(int fd, const struct iovec* iov, int iovcnt, off_t offset) {
fdio_t* io = fd_to_io(fd);
if (io == NULL) {
return ERRNO(EBADF);
}
bool nonblocking = *fdio_get_ioflag(io) & IOFLAG_NONBLOCK;
zx::time deadline = zx::deadline_after(*fdio_get_rcvtimeo(io));
zx_iovec_t zx_iov[iovcnt];
for (int i = 0; i < iovcnt; ++i) {
zx_iov[i] = {
.buffer = iov[i].iov_base,
.capacity = iov[i].iov_len,
};
}
for (;;) {
size_t actual;
zx_status_t status = zxio_read_vector_at(fdio_get_zxio(io), offset, zx_iov, iovcnt, 0, &actual);
if (status == ZX_ERR_SHOULD_WAIT && !nonblocking) {
if (fdio_wait(io, FDIO_EVT_READABLE, deadline, nullptr) != ZX_ERR_TIMED_OUT) {
continue;
}
}
fdio_release(io);
if (status != ZX_OK) {
return ERROR(status);
}
return actual;
}
}
__EXPORT
ssize_t pwritev(int fd, const struct iovec* iov, int iovcnt, off_t offset) {
fdio_t* io = fd_to_io(fd);
if (io == NULL) {
return ERRNO(EBADF);
}
bool nonblocking = *fdio_get_ioflag(io) & IOFLAG_NONBLOCK;
zx::time deadline = zx::deadline_after(*fdio_get_sndtimeo(io));
zx_iovec_t zx_iov[iovcnt];
for (int i = 0; i < iovcnt; ++i) {
zx_iov[i] = {
.buffer = iov[i].iov_base,
.capacity = iov[i].iov_len,
};
}
for (;;) {
size_t actual;
zx_status_t status =
zxio_write_vector_at(fdio_get_zxio(io), offset, zx_iov, iovcnt, 0, &actual);
if (status == ZX_ERR_SHOULD_WAIT && !nonblocking) {
if (fdio_wait(io, FDIO_EVT_WRITABLE, deadline, nullptr) != ZX_ERR_TIMED_OUT) {
continue;
}
}
fdio_release(io);
if (status != ZX_OK) {
return ERROR(status);
}
return actual;
}
}
__EXPORT
ssize_t pread(int fd, void* buf, size_t count, off_t offset) {
struct iovec iov = {};
iov.iov_base = buf;
iov.iov_len = count;
return preadv(fd, &iov, 1, offset);
}
__EXPORT
ssize_t pwrite(int fd, const void* buf, size_t count, off_t offset) {
struct iovec iov = {};
iov.iov_base = const_cast<void*>(buf);
iov.iov_len = count;
return pwritev(fd, &iov, 1, offset);
}
__EXPORT
ssize_t read(int fd, void* buf, size_t count) {
struct iovec iov = {};
iov.iov_base = buf;
iov.iov_len = count;
return readv(fd, &iov, 1);
}
__EXPORT
ssize_t write(int fd, const void* buf, size_t count) {
struct iovec iov = {};
iov.iov_base = const_cast<void*>(buf);
iov.iov_len = count;
return writev(fd, &iov, 1);
}
__EXPORT
int close(int fd) {
mtx_lock(&fdio_lock);
if ((fd < 0) || (fd >= FDIO_MAX_FD) || (fdio_fdtab[fd] == NULL)) {
mtx_unlock(&fdio_lock);
return ERRNO(EBADF);
}
fdio_t* io = fdio_fdtab[fd];
fdio_dupcount_release(io);
fdio_fdtab[fd] = NULL;
if (fdio_get_dupcount(io) > 0) {
// still alive in other fdtab slots
mtx_unlock(&fdio_lock);
fdio_release(io);
return ZX_OK;
} else {
mtx_unlock(&fdio_lock);
int r = fdio_get_ops(io)->close(io);
fdio_release(io);
return STATUS(r);
}
}
static int fdio_dup(int oldfd, int newfd, int starting_fd) {
fdio_t* io = fd_to_io(oldfd);
if (io == NULL) {
return ERRNO(EBADF);
}
int fd = fdio_bind_to_fd(io, newfd, starting_fd);
if (fd < 0) {
fdio_release(io);
}
return fd;
}
__EXPORT
int dup2(int oldfd, int newfd) { return fdio_dup(oldfd, newfd, 0); }
__EXPORT
int dup(int oldfd) { return fdio_dup(oldfd, -1, 0); }
__EXPORT
int dup3(int oldfd, int newfd, int flags) {
// dup3 differs from dup2 in that it fails with EINVAL, rather
// than being a no op, on being given the same fd for both old and
// new.
if (oldfd == newfd) {
return ERRNO(EINVAL);
}
if (flags != 0 && flags != O_CLOEXEC) {
return ERRNO(EINVAL);
}
// TODO(ZX-973) Implement O_CLOEXEC.
return fdio_dup(oldfd, newfd, 0);
}
__EXPORT
int fcntl(int fd, int cmd, ...) {
// Note that it is not safe to pull out the int out of the
// variadic arguments at the top level, as callers are not
// required to pass anything for many of the commands.
#define GET_INT_ARG(ARG) \
va_list args; \
va_start(args, cmd); \
int ARG = va_arg(args, int); \
va_end(args)
switch (cmd) {
case F_DUPFD:
case F_DUPFD_CLOEXEC: {
// TODO(ZX-973) Implement CLOEXEC.
GET_INT_ARG(starting_fd);
return fdio_dup(fd, -1, starting_fd);
}
case F_GETFD: {
fdio_t* io = fd_to_io(fd);
if (io == NULL) {
return ERRNO(EBADF);
}
int flags = (int)(*fdio_get_ioflag(io) & IOFLAG_FD_FLAGS);
// POSIX mandates that the return value be nonnegative if successful.
assert(flags >= 0);
fdio_release(io);
return flags;
}
case F_SETFD: {
fdio_t* io = fd_to_io(fd);
if (io == NULL) {
return ERRNO(EBADF);
}
GET_INT_ARG(flags);
// TODO(ZX-973) Implement CLOEXEC.
*fdio_get_ioflag(io) &= ~IOFLAG_FD_FLAGS;
*fdio_get_ioflag(io) |= (uint32_t)flags & IOFLAG_FD_FLAGS;
fdio_release(io);
return 0;
}
case F_GETFL: {
fdio_t* io = fd_to_io(fd);
if (io == NULL) {
return ERRNO(EBADF);
}
uint32_t flags = 0;
zx_status_t r = fdio_get_ops(io)->get_flags(io, &flags);
if (r == ZX_ERR_NOT_SUPPORTED) {
// We treat this as non-fatal, as it's valid for a remote to
// simply not support FCNTL, but we still want to correctly
// report the state of the (local) NONBLOCK flag
flags = 0;
r = ZX_OK;
}
flags = zxio_flags_to_fdio(flags);
if (*fdio_get_ioflag(io) & IOFLAG_NONBLOCK) {
flags |= O_NONBLOCK;
}
fdio_release(io);
if (r < 0) {
return STATUS(r);
}
return flags;
}
case F_SETFL: {
fdio_t* io = fd_to_io(fd);
if (io == NULL) {
return ERRNO(EBADF);
}
GET_INT_ARG(n);
zx_status_t r;
uint32_t flags = fdio_flags_to_zxio(n & ~O_NONBLOCK);
r = fdio_get_ops(io)->set_flags(io, flags);
// Some remotes don't support setting flags; we
// can adjust their local flags anyway if NONBLOCK
// is the only bit being toggled.
if (r == ZX_ERR_NOT_SUPPORTED && ((n | O_NONBLOCK) == O_NONBLOCK)) {
r = ZX_OK;
}
if (r != ZX_OK) {
n = STATUS(r);
} else {
if (n & O_NONBLOCK) {
*fdio_get_ioflag(io) |= IOFLAG_NONBLOCK;
} else {
*fdio_get_ioflag(io) &= ~IOFLAG_NONBLOCK;
}
n = 0;
}
fdio_release(io);
return n;
}
case F_GETOWN:
case F_SETOWN:
// TODO(kulakowski) Socket support.
return ERRNO(ENOSYS);
case F_GETLK:
case F_SETLK:
case F_SETLKW:
// TODO(kulakowski) Advisory file locking support.
return ERRNO(ENOSYS);
default:
return ERRNO(EINVAL);
}
#undef GET_INT_ARG
}
static_assert(SEEK_SET == int(fio::SeekOrigin::START), "");
static_assert(SEEK_CUR == int(fio::SeekOrigin::CURRENT), "");
static_assert(SEEK_END == int(fio::SeekOrigin::END), "");
__EXPORT
off_t lseek(int fd, off_t offset, int whence) {
fdio_t* io = fd_to_io(fd);
if (io == NULL) {
return ERRNO(EBADF);
}
size_t result = 0u;
zx_status_t status = zxio_seek(fdio_get_zxio(io), offset, zxio_seek_origin_t(whence), &result);
if (status == ZX_ERR_WRONG_TYPE) {
// Although 'ESPIPE' is a bit of a misnomer, it is the valid errno
// for any fd which does not implement seeking (i.e., for pipes,
// sockets, etc).
fdio_release(io);
return ERRNO(ESPIPE);
} else {
fdio_release(io);
return status != ZX_OK ? STATUS(status) : (off_t)result;
}
}
static int truncateat(int dirfd, const char* path, off_t len) {
fdio_t* io;
zx_status_t r;
if ((r = __fdio_open_at(&io, dirfd, path, O_WRONLY, 0)) < 0) {
return ERROR(r);
}
r = fdio_get_ops(io)->truncate(io, len);
fdio_close(io);
fdio_release(io);
return STATUS(r);
}
__EXPORT
int truncate(const char* path, off_t len) { return truncateat(AT_FDCWD, path, len); }
__EXPORT
int ftruncate(int fd, off_t len) {
fdio_t* io = fd_to_io(fd);
if (io == NULL) {
return ERRNO(EBADF);
}
zx_status_t r = fdio_get_ops(io)->truncate(io, len);
fdio_release(io);
return STATUS(r);
}
// Filesystem operations (such as rename and link) which act on multiple paths
// have some additional complexity on Zircon. These operations (eventually) act
// on two pairs of variables: a source parent vnode + name, and a target parent
// vnode + name. However, the loose coupling of these pairs can make their
// correspondence difficult, especially when accessing each parent vnode may
// involve crossing various filesystem boundaries.
//
// To resolve this problem, these kinds of operations involve:
// - Opening the source parent vnode directly.
// - Opening the target parent vnode directly, + acquiring a "vnode token".
// - Sending the real operation + names to the source parent vnode, along with
// the "vnode token" representing the target parent vnode.
//
// Using zircon kernel primitives (cookies) to authenticate the vnode token, this
// allows these multi-path operations to mix absolute / relative paths and cross
// mount points with ease.
static int two_path_op_at(int olddirfd, const char* oldpath, int newdirfd, const char* newpath,
two_path_op fdio_ops::*op_getter) {
char oldname[NAME_MAX + 1];
fdio_t* io_oldparent;
zx_status_t status = ZX_OK;
if ((status = __fdio_opendir_containing_at(&io_oldparent, olddirfd, oldpath, oldname)) < 0) {
return ERROR(status);
}
char newname[NAME_MAX + 1];
fdio_t* io_newparent;
if ((status = __fdio_opendir_containing_at(&io_newparent, newdirfd, newpath, newname)) < 0) {
goto oldparent_open;
}
zx_handle_t token;
status = fdio_get_ops(io_newparent)->get_token(io_newparent, &token);
if (status < 0) {
goto newparent_open;
}
status = (fdio_get_ops(io_oldparent)->*op_getter)(io_oldparent, oldname, strlen(oldname), token,
newname, strlen(newname));
newparent_open:
fdio_get_ops(io_newparent)->close(io_newparent);
fdio_release(io_newparent);
oldparent_open:
fdio_get_ops(io_oldparent)->close(io_oldparent);
fdio_release(io_oldparent);
return STATUS(status);
}
__EXPORT
int renameat(int olddirfd, const char* oldpath, int newdirfd, const char* newpath) {
return two_path_op_at(olddirfd, oldpath, newdirfd, newpath, &fdio_ops::rename);
}
__EXPORT
int rename(const char* oldpath, const char* newpath) {
return two_path_op_at(AT_FDCWD, oldpath, AT_FDCWD, newpath, &fdio_ops::rename);
}
__EXPORT
int link(const char* oldpath, const char* newpath) {
return two_path_op_at(AT_FDCWD, oldpath, AT_FDCWD, newpath, &fdio_ops::link);
}
__EXPORT
int unlink(const char* path) { return unlinkat(AT_FDCWD, path, 0); }
static int vopenat(int dirfd, const char* path, int flags, va_list args) {
fdio_t* io = NULL;
zx_status_t r;
int fd;
uint32_t mode = 0;
if (flags & O_CREAT) {
if (flags & O_DIRECTORY) {
// The behavior of open with O_CREAT | O_DIRECTORY is underspecified
// in POSIX. To help avoid programmer error, we explicitly disallow
// the combination.
return ERRNO(EINVAL);
}
mode = va_arg(args, uint32_t) & 0777;
}
if ((r = __fdio_open_at(&io, dirfd, path, flags, mode)) != ZX_OK) {
return ERROR(r);
}
if (flags & O_NONBLOCK) {
*fdio_get_ioflag(io) |= IOFLAG_NONBLOCK;
}
if ((fd = fdio_bind_to_fd(io, -1, 0)) < 0) {
fdio_get_ops(io)->close(io);
fdio_release(io);
return ERRNO(EMFILE);
}
return fd;
}
__EXPORT
int open(const char* path, int flags, ...) {
va_list ap;
va_start(ap, flags);
int ret = vopenat(AT_FDCWD, path, flags, ap);
va_end(ap);
return ret;
}
__EXPORT
int openat(int dirfd, const char* path, int flags, ...) {
va_list ap;
va_start(ap, flags);
int ret = vopenat(dirfd, path, flags, ap);
va_end(ap);
return ret;
}
__EXPORT
int mkdir(const char* path, mode_t mode) { return mkdirat(AT_FDCWD, path, mode); }
__EXPORT
int mkdirat(int dirfd, const char* path, mode_t mode) {
fdio_t* io = NULL;
zx_status_t r;
mode = (mode & 0777) | S_IFDIR;
if ((r = __fdio_open_at_ignore_eisdir(&io, dirfd, path, O_RDONLY | O_CREAT | O_EXCL, mode)) < 0) {
return ERROR(r);
}
fdio_get_ops(io)->close(io);
fdio_release(io);
return 0;
}
__EXPORT
int fsync(int fd) {
fdio_t* io = fd_to_io(fd);
if (io == NULL) {
return ERRNO(EBADF);
}
zx_status_t status = zxio_sync(fdio_get_zxio(io));
fdio_release(io);
return STATUS(status);
}
__EXPORT
int fdatasync(int fd) {
// TODO(smklein): fdatasync does not need to flush metadata under certain
// circumstances -- however, for now, this implementation will appear
// functionally the same (if a little slower).
return fsync(fd);
}
__EXPORT
int syncfs(int fd) {
// TODO(smklein): Currently, fsync syncs the entire filesystem, not just
// the target file descriptor. These functions should use different sync
// mechanisms, where fsync is more fine-grained.
return fsync(fd);
}
__EXPORT
int fstat(int fd, struct stat* s) {
fdio_t* io = fd_to_io(fd);
if (io == NULL) {
return ERRNO(EBADF);
}
int r = STATUS(fdio_stat(io, s));
fdio_release(io);
return r;
}
__EXPORT
int fstatat(int dirfd, const char* fn, struct stat* s, int flags) {
fdio_t* io;
zx_status_t r;
if ((r = __fdio_open_at(&io, dirfd, fn, O_PATH, 0)) < 0) {
return ERROR(r);
}
r = fdio_stat(io, s);
fdio_close(io);
fdio_release(io);
return STATUS(r);
}
__EXPORT
int stat(const char* fn, struct stat* s) { return fstatat(AT_FDCWD, fn, s, 0); }
__EXPORT
int lstat(const char* path, struct stat* buf) { return stat(path, buf); }
__EXPORT
char* realpath(const char* __restrict filename, char* __restrict resolved) {
ssize_t r;
struct stat st;
char tmp[PATH_MAX];
size_t outlen;
bool is_dir;
if (!filename) {
errno = EINVAL;
return NULL;
}
if (filename[0] != '/') {
// Convert 'filename' from a relative path to an absolute path.
size_t file_len = strlen(filename);
char tmp2[PATH_MAX];
size_t cwd_len = 0;
{
fbl::AutoLock cwd_lock(&fdio_cwd_lock);
cwd_len = strlen(fdio_cwd_path);
if (cwd_len + 1 + file_len >= PATH_MAX) {
errno = ENAMETOOLONG;
return NULL;
}
memcpy(tmp2, fdio_cwd_path, cwd_len);
}
tmp2[cwd_len] = '/';
strcpy(tmp2 + cwd_len + 1, filename);
zx_status_t status = __fdio_cleanpath(tmp2, tmp, &outlen, &is_dir);
if (status != ZX_OK) {
errno = EINVAL;
return NULL;
}
} else {
// Clean the provided absolute path
zx_status_t status = __fdio_cleanpath(filename, tmp, &outlen, &is_dir);
if (status != ZX_OK) {
errno = EINVAL;
return NULL;
}
r = stat(tmp, &st);
if (r < 0) {
return NULL;
}
}
return resolved ? strcpy(resolved, tmp) : strdup(tmp);
}
static zx_status_t zx_utimens(fdio_t* io, const struct timespec times[2], int flags) {
zxio_node_attr_t attr = {};
uint64_t modification_time;
// Extract modify time.
if (times == NULL || times[1].tv_nsec == UTIME_NOW) {
zx_time_t now;
zx_status_t status = zx_clock_get(ZX_CLOCK_UTC, &now);
if (status != ZX_OK) {
return status;
}
modification_time = now;
} else {
modification_time = zx_time_add_duration(ZX_SEC(times[1].tv_sec), times[1].tv_nsec);
}
if (times == NULL || times[1].tv_nsec != UTIME_OMIT) {
// For setattr, tell which fields are valid.
ZXIO_NODE_ATTR_SET(attr, modification_time, modification_time);
}
// set time(s) on underlying object
return fdio_get_ops(io)->set_attr(io, &attr);
}
__EXPORT
int utimensat(int dirfd, const char* path, const struct timespec times[2], int flags) {
fdio_t* io;
zx_status_t r;
// TODO(orr): AT_SYMLINK_NOFOLLOW
if ((flags & AT_SYMLINK_NOFOLLOW) != 0) {
// Allow this flag - don't return an error. Fuchsia does not support
// symlinks, so don't break utilities (like tar) that use this flag.
}
if ((r = __fdio_open_at_ignore_eisdir(&io, dirfd, path, O_WRONLY, 0)) < 0) {
return ERROR(r);
}
r = zx_utimens(io, times, 0);
fdio_close(io);
fdio_release(io);
return STATUS(r);
}
__EXPORT
int futimens(int fd, const struct timespec times[2]) {
fdio_t* io = fd_to_io(fd);
zx_status_t r = zx_utimens(io, times, 0);
fdio_release(io);
return STATUS(r);
}
__EXPORT
int pipe2(int pipefd[2], int flags) {
const int allowed_flags = O_NONBLOCK | O_CLOEXEC;
if (flags & ~allowed_flags) {
return ERRNO(EINVAL);
}
fdio_t *a, *b;
int r = fdio_pipe_pair(&a, &b);
if (r < 0) {
return ERROR(r);
}
pipefd[0] = fdio_bind_to_fd(a, -1, 0);
if (pipefd[0] < 0) {
int errno_ = errno;
fdio_close(a);
fdio_release(a);
fdio_close(b);
fdio_release(b);
return ERRNO(errno_);
}
pipefd[1] = fdio_bind_to_fd(b, -1, 0);
if (pipefd[1] < 0) {
int errno_ = errno;
close(pipefd[0]);
fdio_close(b);
fdio_release(b);
return ERRNO(errno_);
}
return 0;
}
__EXPORT
int pipe(int pipefd[2]) { return pipe2(pipefd, 0); }
__EXPORT
int socketpair(int domain, int type, int protocol, int fd[2]) {
if (type != SOCK_STREAM) { // TODO(jamesr): SOCK_DGRAM
errno = EPROTOTYPE;
return -1;
}
if (domain != AF_UNIX) {
errno = EAFNOSUPPORT;
return -1;
}
if (protocol != 0) {
errno = EPROTONOSUPPORT;
return -1;
}
return pipe(fd);
}
__EXPORT
int faccessat(int dirfd, const char* filename, int amode, int flag) {
// First, check that the flags and amode are valid.
const int allowed_flags = AT_EACCESS;
if (flag & (~allowed_flags)) {
return ERRNO(EINVAL);
}
// amode is allowed to be either a subset of this mask, or just F_OK.
const int allowed_modes = R_OK | W_OK | X_OK;
if (amode != F_OK && (amode & (~allowed_modes))) {
return ERRNO(EINVAL);
}
fdio_t* io;
zx_status_t status;
if (amode == F_OK) {
// Check that the file exists a la fstatat.
if ((status = __fdio_open_at(&io, dirfd, filename, O_PATH, 0)) < 0) {
return ERROR(status);
}
struct stat s;
status = fdio_stat(io, &s);
} else {
// Check that the file has each of the permissions in mode.
// Ignore X_OK, since it does not apply to our permission model
amode &= ~X_OK;
uint32_t rights_flags = 0;
switch (amode & (R_OK | W_OK)) {
case R_OK:
rights_flags = O_RDONLY;
break;
case W_OK:
rights_flags = O_WRONLY;
break;
case R_OK | W_OK:
rights_flags = O_RDWR;
break;
}
if ((status = __fdio_open_at_ignore_eisdir(&io, dirfd, filename, rights_flags, 0)) < 0) {
return ERROR(status);
}
}
fdio_close(io);
fdio_release(io);
return STATUS(status);
}
__EXPORT
char* getcwd(char* buf, size_t size) {
char tmp[PATH_MAX];
if (buf == NULL) {
buf = tmp;
size = PATH_MAX;
} else if (size == 0) {
errno = EINVAL;
return NULL;
}
char* out = NULL;
{
fbl::AutoLock lock(&fdio_cwd_lock);
size_t len = strlen(fdio_cwd_path) + 1;
if (len < size) {
memcpy(buf, fdio_cwd_path, len);
out = buf;
} else {
errno = ERANGE;
}
}
if (out == tmp) {
out = strdup(tmp);
}
return out;
}
void fdio_chdir(fdio_t* io, const char* path) {
fbl::AutoLock cwd_lock(&fdio_cwd_lock);
update_cwd_path(path);
fbl::AutoLock lock(&fdio_lock);
fdio_t* old = fdio_cwd_handle;
fdio_cwd_handle = io;
fdio_get_ops(old)->close(old);
fdio_release(old);
}
__EXPORT
int chdir(const char* path) {
fdio_t* io;
zx_status_t r;
if ((r = __fdio_open(&io, path, O_RDONLY | O_DIRECTORY, 0)) < 0) {
return STATUS(r);
}
fdio_chdir(io, path);
return 0;
}
struct __dirstream {
mtx_t lock;
// fd number of the directory under iteration.
int fd;
// The iterator object for reading directory entries.
zxio_dirent_iterator_t iterator = {};
// A single directory entry returned to user; updated by |readdir|.
struct dirent de = {};
// If |iterator| is initialized. The |iterator| is initialized lazily.
bool is_iterator_initialized = false;
};
static DIR* internal_opendir(int fd) {
DIR* dir = new __dirstream;
mtx_init(&dir->lock, mtx_plain);
dir->fd = fd;
return dir;
}
__EXPORT
DIR* opendir(const char* name) {
int fd = open(name, O_RDONLY | O_DIRECTORY);
if (fd < 0)
return NULL;
DIR* dir = internal_opendir(fd);
if (dir == NULL)
close(fd);
return dir;
}
__EXPORT
DIR* fdopendir(int fd) {
// Check the fd for validity, but we'll just store the fd
// number so we don't save the fdio_t pointer.
fdio_t* io = fd_to_io(fd);
if (io == NULL) {
errno = EBADF;
return NULL;
}
// TODO(mcgrathr): Technically this should verify that it's
// really a directory and fail with ENOTDIR if not. But
// that's not so easy to do, so don't bother for now.
fdio_release(io);
return internal_opendir(fd);
}
__EXPORT
int closedir(DIR* dir) {
if (dir->is_iterator_initialized) {
fdio_t* io = fd_to_io(dir->fd);
fdio_get_ops(io)->dirent_iterator_destroy(io, &dir->iterator);
}
close(dir->fd);
delete dir;
return 0;
}
__EXPORT
struct dirent* readdir(DIR* dir) {
fbl::AutoLock lock(&dir->lock);
struct dirent* de = &dir->de;
zxio_dirent_t* entry = nullptr;
fdio_t* io = fd_to_io(dir->fd);
// Lazy initialize the iterator.
if (!dir->is_iterator_initialized) {
zx_status_t status =
fdio_get_ops(io)->dirent_iterator_init(io, &dir->iterator, fdio_get_zxio(io));
if (status != ZX_OK) {
errno = fdio_status_to_errno(status);
return nullptr;
}
dir->is_iterator_initialized = true;
}
zx_status_t status = fdio_get_ops(io)->dirent_iterator_next(io, &dir->iterator, &entry);
if (status == ZX_ERR_NOT_FOUND) {
// Reached the end.
ZX_DEBUG_ASSERT(!entry);
return nullptr;
}
if (status != ZX_OK) {
errno = fdio_status_to_errno(status);
return nullptr;
}
de->d_ino = entry->has.id ? entry->id : fio::INO_UNKNOWN;
de->d_off = 0;
// The d_reclen field is nonstandard, but existing code
// may expect it to be useful as an upper bound on the
// length of the name.
de->d_reclen =
static_cast<unsigned short>(offsetof(struct dirent, d_name) + entry->name_length + 1);
if (entry->has.protocols) {
de->d_type = ([](zxio_node_protocols_t protocols) -> unsigned char {
if (protocols & ZXIO_NODE_PROTOCOL_DIRECTORY)
return DT_DIR;
if (protocols & ZXIO_NODE_PROTOCOL_FILE)
return DT_REG;
if (protocols & ZXIO_NODE_PROTOCOL_MEMORY)
return DT_REG;
if (protocols & ZXIO_NODE_PROTOCOL_POSIX_SOCKET)
return DT_SOCK;
if (protocols & ZXIO_NODE_PROTOCOL_PIPE)
return DT_FIFO;
if (protocols & ZXIO_NODE_PROTOCOL_DEVICE)
return DT_BLK;
if (protocols & ZXIO_NODE_PROTOCOL_TTY)
return DT_CHR;
if (protocols & ZXIO_NODE_PROTOCOL_DEBUGLOG)
return DT_CHR;
// There is no good analogue for FIDL services in POSIX land.
if (protocols & ZXIO_NODE_PROTOCOL_CONNECTOR)
return DT_UNKNOWN;
return DT_UNKNOWN;
})(entry->protocols);
} else {
de->d_type = DT_UNKNOWN;
}
memcpy(de->d_name, entry->name, entry->name_length);
de->d_name[entry->name_length] = '\0';
return de;
}
__EXPORT
void rewinddir(DIR* dir) {
fbl::AutoLock lock(&dir->lock);
if (dir->is_iterator_initialized) {
fdio_t* io = fd_to_io(dir->fd);
fdio_get_ops(io)->dirent_iterator_destroy(io, &dir->iterator);
dir->is_iterator_initialized = false;
}
}
__EXPORT
int dirfd(DIR* dir) { return dir->fd; }
__EXPORT
int isatty(int fd) {
fdio_t* io = fd_to_io(fd);
if (io == NULL) {
errno = EBADF;
return 0;
}
bool tty;
zx_status_t status = zxio_isatty(fdio_get_zxio(io), &tty);
int ret;
if ((status == ZX_OK) && tty) {
ret = 1;
} else {
ret = 0;
errno = ENOTTY;
}
fdio_release(io);
return ret;
}
__EXPORT
mode_t umask(mode_t mask) {
mode_t oldmask;
fbl::AutoLock lock(&fdio_lock);
oldmask = __fdio_global_state.umask;
__fdio_global_state.umask = mask & 0777;
return oldmask;
}
__EXPORT
int fdio_handle_fd(zx_handle_t h, zx_signals_t signals_in, zx_signals_t signals_out,
bool shared_handle) {
fdio_t* io = fdio_waitable_create(h, signals_in, signals_out, shared_handle);
int fd = fdio_bind_to_fd(io, -1, 0);
if (fd < 0) {
fdio_close(io);
fdio_release(io);
}
return fd;
}
// from fdio/unsafe.h, to support message-loop integration
__EXPORT
void fdio_unsafe_wait_begin(fdio_t* io, uint32_t events, zx_handle_t* handle_out,
zx_signals_t* signals_out) {
return fdio_get_ops(io)->wait_begin(io, events, handle_out, signals_out);
}
__EXPORT
void fdio_unsafe_wait_end(fdio_t* io, zx_signals_t signals, uint32_t* events_out) {
return fdio_get_ops(io)->wait_end(io, signals, events_out);
}
__EXPORT
void fdio_unsafe_release(fdio_t* io) { fdio_release(io); }
// TODO: getrlimit(RLIMIT_NOFILE, ...)
#define MAX_POLL_NFDS 1024
__EXPORT
int ppoll(struct pollfd* fds, nfds_t n, const struct timespec* timeout_ts,
const sigset_t* sigmask) {
if (sigmask) {
return ERRNO(ENOSYS);
}
if (n > MAX_POLL_NFDS) {
return ERRNO(EINVAL);
}
fdio_t* ios[n];
nfds_t ios_used_count = 0;
zx_status_t r = ZX_OK;
nfds_t nvalid = 0;
zx_wait_item_t items[n];
for (nfds_t i = 0; i < n; i++) {
struct pollfd* pfd = &fds[i];
pfd->revents = 0; // initialize to zero
ios[i] = NULL;
if (pfd->fd < 0) {
// if fd is negative, the entry is invalid
continue;
}
fdio_t* io;
if ((io = fd_to_io(pfd->fd)) == NULL) {
// fd is not opened
pfd->revents = POLLNVAL;
continue;
}
ios[i] = io;
ios_used_count = i + 1;
zx_handle_t h;
zx_signals_t sigs;
fdio_get_ops(io)->wait_begin(io, pfd->events, &h, &sigs);
if (h == ZX_HANDLE_INVALID) {
// wait operation is not applicable to the handle
r = ZX_ERR_INVALID_ARGS;
break;
}
items[nvalid].handle = h;
items[nvalid].waitfor = sigs;
items[nvalid].pending = 0;
nvalid++;
}
int nfds = 0;
if (r == ZX_OK && nvalid > 0) {
zx_time_t tmo = ZX_TIME_INFINITE;
// Check for overflows on every operation.
if (timeout_ts && timeout_ts->tv_sec >= 0 && timeout_ts->tv_nsec >= 0 &&
timeout_ts->tv_sec <= INT64_MAX / ZX_SEC(1)) {
zx_duration_t seconds_duration = ZX_SEC(timeout_ts->tv_sec);
zx_duration_t duration = zx_duration_add_duration(seconds_duration, timeout_ts->tv_nsec);
if (duration >= seconds_duration) {
tmo = zx_deadline_after(duration);
}
}
r = zx_object_wait_many(items, nvalid, tmo);
// pending signals could be reported on ZX_ERR_TIMED_OUT case as well
if (r == ZX_OK || r == ZX_ERR_TIMED_OUT) {
nfds_t j = 0; // j counts up on a valid entry
for (nfds_t i = 0; i < n; i++) {
struct pollfd* pfd = &fds[i];
fdio_t* io = ios[i];
if (io == NULL) {
// skip an invalid entry
continue;
}
if (j < nvalid) {
uint32_t events = 0;
fdio_get_ops(io)->wait_end(io, items[j].pending, &events);
// mask unrequested events except HUP/ERR
pfd->revents = static_cast<short>(events) & (pfd->events | POLLHUP | POLLERR);
if (pfd->revents != 0) {
nfds++;
}
}
j++;
}
}
}
for (nfds_t i = 0; i < ios_used_count; i++) {
if (ios[i]) {
fdio_release(ios[i]);
}
}
return (r == ZX_OK || r == ZX_ERR_TIMED_OUT) ? nfds : ERROR(r);
}
__EXPORT
int poll(struct pollfd* fds, nfds_t n, int timeout) {
struct timespec timeout_ts = {timeout / 1000, (timeout % 1000) * 1000000};
struct timespec* ts = timeout >= 0 ? &timeout_ts : NULL;
return ppoll(fds, n, ts, NULL);
}
__EXPORT
int select(int n, fd_set* __restrict rfds, fd_set* __restrict wfds, fd_set* __restrict efds,
struct timeval* __restrict tv) {
if (n > FD_SETSIZE || n < 1) {
return ERRNO(EINVAL);
}
fdio_t* ios[n];
int ios_used_max = -1;
zx_status_t r = ZX_OK;
int nvalid = 0;
zx_wait_item_t items[n];
for (int fd = 0; fd < n; fd++) {
ios[fd] = NULL;
uint32_t events = 0;
if (rfds && FD_ISSET(fd, rfds))
events |= POLLIN;
if (wfds && FD_ISSET(fd, wfds))
events |= POLLOUT;
if (efds && FD_ISSET(fd, efds))
events |= POLLERR;
if (events == 0) {
continue;
}
fdio_t* io;
if ((io = fd_to_io(fd)) == NULL) {
r = ZX_ERR_BAD_HANDLE;
break;
}
ios[fd] = io;
ios_used_max = fd;
zx_handle_t h;
zx_signals_t sigs;
fdio_get_ops(io)->wait_begin(io, events, &h, &sigs);
if (h == ZX_HANDLE_INVALID) {
r = ZX_ERR_INVALID_ARGS;
break;
}
items[nvalid].handle = h;
items[nvalid].waitfor = sigs;
items[nvalid].pending = 0;
nvalid++;
}
int nfds = 0;
if (r == ZX_OK && nvalid > 0) {
zx_time_t tmo =
(tv == NULL)
? ZX_TIME_INFINITE
: zx_deadline_after(zx_duration_add_duration(ZX_SEC(tv->tv_sec), ZX_USEC(tv->tv_usec)));
r = zx_object_wait_many(items, nvalid, tmo);
// pending signals could be reported on ZX_ERR_TIMED_OUT case as well
if (r == ZX_OK || r == ZX_ERR_TIMED_OUT) {
int j = 0; // j counts up on a valid entry
for (int fd = 0; fd < n; fd++) {
fdio_t* io = ios[fd];
if (io == NULL) {
// skip an invalid entry
continue;
}
if (j < nvalid) {
uint32_t events = 0;
fdio_get_ops(io)->wait_end(io, items[j].pending, &events);
if (rfds && FD_ISSET(fd, rfds)) {
if (events & POLLIN) {
nfds++;
} else {
FD_CLR(fd, rfds);
}
}
if (wfds && FD_ISSET(fd, wfds)) {
if (events & POLLOUT) {
nfds++;
} else {
FD_CLR(fd, wfds);
}
}
if (efds && FD_ISSET(fd, efds)) {
if (events & POLLERR) {
nfds++;
} else {
FD_CLR(fd, efds);
}
}
} else {
if (rfds) {
FD_CLR(fd, rfds);
}
if (wfds) {
FD_CLR(fd, wfds);
}
if (efds) {
FD_CLR(fd, efds);
}
}
j++;
}
}
}
for (int i = 0; i <= ios_used_max; i++) {
if (ios[i]) {
fdio_release(ios[i]);
}
}
return (r == ZX_OK || r == ZX_ERR_TIMED_OUT) ? nfds : ERROR(r);
}
__EXPORT
int ioctl(int fd, int req, ...) {
fdio_t* io;
if ((io = fd_to_io(fd)) == NULL) {
return ERRNO(EBADF);
}
va_list ap;
va_start(ap, req);
zx_status_t r = fdio_get_ops(io)->posix_ioctl(io, req, ap);
va_end(ap);
fdio_release(io);
return STATUS(r);
}
__EXPORT
ssize_t sendto(int fd, const void* buf, size_t buflen, int flags, const struct sockaddr* addr,
socklen_t addrlen) {
struct iovec iov;
iov.iov_base = const_cast<void*>(buf);
iov.iov_len = buflen;
struct msghdr msg = {};
msg.msg_name = const_cast<struct sockaddr*>(addr);
msg.msg_namelen = addrlen;
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
return sendmsg(fd, &msg, flags);
}
__EXPORT
ssize_t recvfrom(int fd, void* __restrict buf, size_t buflen, int flags,
struct sockaddr* __restrict addr, socklen_t* __restrict addrlen) {
struct iovec iov;
iov.iov_base = buf;
iov.iov_len = buflen;
struct msghdr msg = {};
msg.msg_name = addr;
if (addrlen != nullptr) {
msg.msg_namelen = *addrlen;
}
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
ssize_t n = recvmsg(fd, &msg, flags);
if (addrlen != nullptr) {
*addrlen = msg.msg_namelen;
}
return n;
}
__EXPORT
ssize_t sendmsg(int fd, const struct msghdr* msg, int flags) {
fdio_t* io = fd_to_io(fd);
if (io == NULL) {
return ERRNO(EBADF);
}
// The |flags| are typically used to express intent *not* to issue SIGPIPE
// via MSG_NOSIGNAL. Applications use this frequently to avoid having to
// install additional signal handlers to handle cases where connection has
// been closed by remote end.
bool nonblocking = (*fdio_get_ioflag(io) & IOFLAG_NONBLOCK) || (flags & MSG_DONTWAIT);
flags &= ~MSG_DONTWAIT;
zx::time deadline = zx::deadline_after(*fdio_get_sndtimeo(io));
for (;;) {
size_t actual;
int16_t out_code;
zx_status_t status = fdio_get_ops(io)->sendmsg(io, msg, flags, &actual, &out_code);
if ((status == ZX_ERR_SHOULD_WAIT || (status == ZX_OK && out_code == EWOULDBLOCK)) &&
!nonblocking) {
uint32_t pending;
switch (fdio_wait(io, FDIO_EVT_WRITABLE, deadline, &pending)) {
case ZX_ERR_TIMED_OUT:
break;
case ZX_OK:
if (pending & POLLHUP) {
status = ZX_ERR_CONNECTION_RESET;
break;
}
__FALLTHROUGH;
default:
continue;
}
}
fdio_release(io);
if (status != ZX_OK) {
return ERROR(status);
}
if (out_code) {
return ERRNO(out_code);
}
return actual;
}
}
__EXPORT
ssize_t recvmsg(int fd, struct msghdr* msg, int flags) {
fdio_t* io = fd_to_io(fd);
if (io == NULL) {
return ERRNO(EBADF);
}
bool nonblocking = (*fdio_get_ioflag(io) & IOFLAG_NONBLOCK) || (flags & MSG_DONTWAIT);
flags &= ~MSG_DONTWAIT;
zx::time deadline = zx::deadline_after(*fdio_get_rcvtimeo(io));
for (;;) {
size_t actual;
int16_t out_code;
zx_status_t status = fdio_get_ops(io)->recvmsg(io, msg, flags, &actual, &out_code);
if ((status == ZX_ERR_SHOULD_WAIT || (status == ZX_OK && out_code == EWOULDBLOCK)) &&
!nonblocking) {
if (fdio_wait(io, FDIO_EVT_READABLE, deadline, nullptr) != ZX_ERR_TIMED_OUT) {
continue;
}
}
fdio_release(io);
if (status != ZX_OK) {
return ERROR(status);
}
if (out_code) {
return ERRNO(out_code);
}
return actual;
}
}
__EXPORT
int shutdown(int fd, int how) {
fdio_t* io = fd_to_io(fd);
if (io == nullptr) {
return ERRNO(EBADF);
}
int16_t out_code;
zx_status_t status = fdio_get_ops(io)->shutdown(io, how, &out_code);
fdio_release(io);
if (status != ZX_OK) {
return ERROR(status);
}
if (out_code) {
return ERRNO(out_code);
}
return out_code;
}
// The common denominator between the Linux-y fstatfs and the POSIX
// fstatvfs, which align on most fields. The fs version is more easily
// computed from the fio::FilesystemInfo, so this takes a struct
// statfs.
static int fs_stat(int fd, struct statfs* buf) {
fdio_t* io;
if ((io = fd_to_io(fd)) == NULL) {
return ERRNO(EBADF);
}
zx_handle_t handle = fdio_unsafe_borrow_channel(io);
if (handle == ZX_HANDLE_INVALID) {
fdio_release(io);
return ERRNO(ENOTSUP);
}
auto result = fio::DirectoryAdmin::Call::QueryFilesystem(zx::unowned_channel(handle));
fdio_release(io);
if (result.status() != ZX_OK) {
return ERROR(result.status());
}
fio::DirectoryAdmin::QueryFilesystemResponse* response = result.Unwrap();
if (response->s != ZX_OK) {
return ERROR(response->s);
}
fio::FilesystemInfo* info = response->info;
if (info == nullptr) {
return ERRNO(EIO);
}
info->name[fio::MAX_FS_NAME_BUFFER - 1] = '\0';
struct statfs stats = {};
if (info->block_size) {
stats.f_bsize = info->block_size;
stats.f_blocks = info->total_bytes / stats.f_bsize;
stats.f_bfree = stats.f_blocks - info->used_bytes / stats.f_bsize;
}
stats.f_bavail = stats.f_bfree;
stats.f_files = info->total_nodes;
stats.f_ffree = info->total_nodes - info->used_nodes;
stats.f_namelen = info->max_filename_size;
stats.f_type = info->fs_type;
stats.f_fsid.__val[0] = static_cast<int>(info->fs_id & 0xffffffff);
stats.f_fsid.__val[1] = static_cast<int>(info->fs_id >> 32u);
*buf = stats;
return 0;
}
__EXPORT
int fstatfs(int fd, struct statfs* buf) { return fs_stat(fd, buf); }
__EXPORT
int statfs(const char* path, struct statfs* buf) {
int fd = open(path, O_RDONLY | O_CLOEXEC);
if (fd < 0) {
return fd;
}
int rv = fstatfs(fd, buf);
close(fd);
return rv;
}
__EXPORT
int fstatvfs(int fd, struct statvfs* buf) {
struct statfs stats = {};
int result = fs_stat(fd, &stats);
if (result >= 0) {
struct statvfs vstats = {};
// The following fields are 1-1 between the Linux statfs
// definition and the POSIX statvfs definition.
vstats.f_bsize = stats.f_bsize;
vstats.f_blocks = stats.f_blocks;
vstats.f_bfree = stats.f_bfree;
vstats.f_bavail = stats.f_bavail;
vstats.f_files = stats.f_files;
vstats.f_ffree = stats.f_ffree;
vstats.f_flag = stats.f_flags;
vstats.f_namemax = stats.f_namelen;
// The following fields have slightly different semantics
// between the two.
// The two have different representations for the fsid.
vstats.f_fsid = stats.f_fsid.__val[0] + (((uint64_t)stats.f_fsid.__val[1]) << 32);
// The statvfs "fragment size" value best corresponds to the
// FilesystemInfo "block size" value.
vstats.f_frsize = stats.f_bsize;
// The statvfs struct distinguishes between available files,
// and available files for unprivileged processes. fuchsia.io
// makes no such distinction, so use the same value for both.
vstats.f_favail = stats.f_ffree;
// Finally, the f_type and f_spare fields on struct statfs
// have no equivalent for struct statvfs.
*buf = vstats;
}
return result;
}
__EXPORT
int statvfs(const char* path, struct statvfs* buf) {
int fd = open(path, O_RDONLY | O_CLOEXEC);
if (fd < 0) {
return fd;
}
int rv = fstatvfs(fd, buf);
close(fd);
return rv;
}
// extern "C" is required here, since the corresponding declaration is in an internal musl header:
// zircon/third_party/ulib/musl/src/internal/libc.h
extern "C" __EXPORT int _fd_open_max(void) { return FDIO_MAX_FD; }