Skip to content

Commit

Permalink
chore: Use new "at" syscalls when possible
Browse files Browse the repository at this point in the history 
For many IO syscalls such as `open` and `mkdir`, use the new `at`
version that takes a FD/path pair instead.

On newer architectures like `aarch64`, the traditional path-only version
is not available and causes compile errors.
  • Loading branch information
@trungnt2910
trungnt2910 committed Mar 5, 2024
1 parent f265b90 commit b80e6d9
Show file tree
Hide file tree
Showing 3 changed files with 32 additions and 23 deletions.
40 changes: 22 additions & 18 deletions monika/linux/io.cpp
View file
Expand Up @@ -260,13 +260,13 @@ int _moni_read_link(int fd, const char* path, char* buffer, size_t *_bufferSize)
}

struct stat linuxStat;
status = LINUX_SYSCALL2(__NR_lstat, hostPath, &linuxStat);
status = LINUX_SYSCALL4(__NR_newfstatat, AT_FDCWD, hostPath, &linuxStat, AT_SYMLINK_NOFOLLOW);
if (status < 0)
{
return LinuxToB(-status);
}

status = LINUX_SYSCALL3(__NR_readlink, hostPath, buffer, *_bufferSize);
status = LINUX_SYSCALL4(__NR_readlinkat, AT_FDCWD, hostPath, buffer, *_bufferSize);

if (status < 0)
{
Expand All @@ -292,7 +292,7 @@ status_t _moni_create_symlink(int fd, const char* path, const char* toPath, int
return status;
}

status = LINUX_SYSCALL2(__NR_symlink, toPath, hostPath);
status = LINUX_SYSCALL3(__NR_symlinkat, toPath, AT_FDCWD, hostPath);

if (status < 0)
{
Expand Down Expand Up @@ -524,11 +524,11 @@ int _moni_open(int fd, const char* path, int openMode, int perms)
linuxFlags |= O_NOFOLLOW;
}

int result = LINUX_SYSCALL3(__NR_open, hostPath, linuxFlags, linuxMode);
int result = LINUX_SYSCALL4(__NR_openat, AT_FDCWD, hostPath, linuxFlags, linuxMode);

if (result == -ELOOP && !shouldFailWithEloop)
{
result = LINUX_SYSCALL3(__NR_open, hostPath, linuxFlags | O_PATH, linuxMode);
result = LINUX_SYSCALL4(__NR_openat, AT_FDCWD, hostPath, linuxFlags | O_PATH, linuxMode);
}

if (result < 0)
Expand Down Expand Up @@ -694,7 +694,7 @@ int _moni_normalize_path(const char* userPath, bool traverseLink, char* buffer)

int _moni_create_pipe(int *fds)
{
long result = LINUX_SYSCALL1(__NR_pipe, fds);
long result = LINUX_SYSCALL2(__NR_pipe2, fds, 0);

if (result < 0)
{
Expand Down Expand Up @@ -728,7 +728,7 @@ status_t _moni_create_fifo(int fd, const char* path, mode_t perms)
return status;
}

status = LINUX_SYSCALL3(__NR_mknod, hostPath, perms | S_IFIFO, 0);
status = LINUX_SYSCALL4(__NR_mknodat, AT_FDCWD, hostPath, perms | S_IFIFO, 0);
if (status < 0)
{
return LinuxToB(-status);
Expand Down Expand Up @@ -759,7 +759,7 @@ int _moni_rename(int oldDir, const char* oldpath, int newDir, const char* newpat
return status;
}

status = LINUX_SYSCALL2(__NR_rename, oldHostPath, newHostPath);
status = LINUX_SYSCALL4(__NR_renameat, AT_FDCWD, oldHostPath, AT_FDCWD, newHostPath);

if (status < 0)
{
Expand Down Expand Up @@ -809,7 +809,7 @@ int _moni_open_dir(int fd, const char* path)
return expandStatus;
}

int result = LINUX_SYSCALL2(__NR_open, hostPath, O_DIRECTORY);
int result = LINUX_SYSCALL4(__NR_openat, AT_FDCWD, hostPath, O_DIRECTORY, 0);

if (result < 0)
{
Expand All @@ -828,7 +828,7 @@ int _moni_open_dir(int fd, const char* path)

status_t _moni_open_parent_dir(int fd, char* name, size_t nameLength)
{
long result = LINUX_SYSCALL3(__NR_openat, fd, "..", O_DIRECTORY);
long result = LINUX_SYSCALL4(__NR_openat, fd, "..", O_DIRECTORY, 0);

if (result < 0)
{
Expand Down Expand Up @@ -906,7 +906,7 @@ int _moni_dup2(int ofd, int nfd)
return HAIKU_POSIX_EBADF;
}

int result = LINUX_SYSCALL2(__NR_dup2, ofd, nfd);
int result = LINUX_SYSCALL3(__NR_dup3, ofd, nfd, 0);

if (result < 0)
{
Expand Down Expand Up @@ -1133,7 +1133,7 @@ status_t _moni_create_dir(int fd, const char* path, int perms)
return status;
}

status = LINUX_SYSCALL2(__NR_mkdir, hostPath, ModeBToLinux(perms));
status = LINUX_SYSCALL3(__NR_mkdirat, AT_FDCWD, hostPath, ModeBToLinux(perms));

if (status < 0)
{
Expand All @@ -1151,7 +1151,11 @@ status_t _moni_remove_dir(int fd, const char* path)
long status = GET_SERVERCALLS()->vchroot_expandat(fd, path, strlen(path),
false, hostPath, sizeof(hostPath));

#ifdef __NR_rmdir
status = LINUX_SYSCALL1(__NR_rmdir, hostPath);
#else
status = LINUX_SYSCALL3(__NR_unlinkat, AT_FDCWD, hostPath, AT_REMOVEDIR);
#endif

if (status < 0)
{
Expand Down Expand Up @@ -1216,7 +1220,7 @@ status_t _moni_open_dir_entry_ref(haiku_dev_t device, haiku_ino_t inode, const c
return status;
}

status = LINUX_SYSCALL2(__NR_open, hostPath, O_DIRECTORY);
status = LINUX_SYSCALL4(__NR_openat, AT_FDCWD, hostPath, O_DIRECTORY, 0);
if (status < 0)
{
return LinuxToB(-status);
Expand Down Expand Up @@ -1269,11 +1273,11 @@ status_t _moni_open_entry_ref(haiku_dev_t device, haiku_ino_t inode, const char*
linuxFlags |= O_NOFOLLOW;
}

status = LINUX_SYSCALL3(__NR_open, hostPath, linuxFlags, linuxMode);
status = LINUX_SYSCALL4(__NR_openat, AT_FDCWD, hostPath, linuxFlags, linuxMode);

if (status == -ELOOP && !shouldFailWithEloop)
{
status = LINUX_SYSCALL3(__NR_open, hostPath, linuxFlags | O_PATH, linuxMode);
status = LINUX_SYSCALL4(__NR_openat, AT_FDCWD, hostPath, linuxFlags | O_PATH, linuxMode);
}

if (status < 0)
Expand Down Expand Up @@ -1346,7 +1350,7 @@ int _moni_open_attr(int fd, const char* path, const char *name,
int linuxMode = OFlagsBToLinux(openMode & ~HAIKU_O_NOTRAVERSE);
int linuxPerms = 0777;

status = LINUX_SYSCALL3(__NR_open, hostPath, linuxMode, linuxPerms);
status = LINUX_SYSCALL4(__NR_openat, AT_FDCWD, hostPath, linuxMode, linuxPerms);

if (status < 0)
{
Expand Down Expand Up @@ -1375,7 +1379,7 @@ int _moni_open_attr_dir(int fd, const char* path, bool traverseLeafLink)
return status;
}

status = LINUX_SYSCALL2(__NR_open, hostPath, O_DIRECTORY);
status = LINUX_SYSCALL4(__NR_openat, AT_FDCWD, hostPath, O_DIRECTORY, 0);

if (status < 0)
{
Expand Down Expand Up @@ -1490,4 +1494,4 @@ int FlockFlagsBToLinux(int flockFlags)
linuxFlags |= LOCK_UN;
}
return linuxFlags;
}
}
6 changes: 3 additions & 3 deletions monika/linux/mman.cpp
View file
Expand Up @@ -185,7 +185,7 @@ area_id MONIKA_EXPORT _moni_clone_area(const char *name, void **address,
mmap_flags |= MAP_SHARED;
mmap_flags &= ~MAP_PRIVATE;

int fd = LINUX_SYSCALL3(__NR_open, hostPath, open_flags, 0);
int fd = LINUX_SYSCALL4(__NR_openat, AT_FDCWD, hostPath, open_flags, 0);
if (fd < 0)
{
return LinuxToB(-fd);
Expand Down Expand Up @@ -1152,7 +1152,7 @@ int ShareArea(void* mappedAddr, size_t size, int areaId,
bool ownsFd = false;
if (hostPath[0] != '\0')
{
fd = LINUX_SYSCALL2(__NR_open, hostPath, open_flags);
fd = LINUX_SYSCALL4(__NR_openat, AT_FDCWD, hostPath, open_flags, 0);
offset = 0;
if (fd < 0)
{
Expand Down Expand Up @@ -1197,4 +1197,4 @@ int LockArea(void* mappedAddr, size_t size, uint32 lock)
}

return LinuxToB(-status);
}
}
9 changes: 7 additions & 2 deletions monika/linux/realpath.cpp
View file
Expand Up @@ -30,6 +30,7 @@
#include <sys/stat.h>

#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
Expand Down Expand Up @@ -139,7 +140,7 @@ long realpath(const char *path, char resolved[PATH_MAX], bool resolveSymlinks)
{
return -ENAMETOOLONG;
}
status = LINUX_SYSCALL2(__NR_lstat, resolved, &sb);
status = LINUX_SYSCALL4(__NR_newfstatat, AT_FDCWD, resolved, &sb, AT_SYMLINK_NOFOLLOW);
if (status < 0)
{
if (status == -ENOENT && p == NULL)
Expand All @@ -154,7 +155,11 @@ long realpath(const char *path, char resolved[PATH_MAX], bool resolveSymlinks)
{
return -ELOOP;
}
#ifdef __NR_readlink
slen = LINUX_SYSCALL3(__NR_readlink, resolved, symlink, sizeof(symlink) - 1);
#else
slen = LINUX_SYSCALL4(__NR_readlinkat, AT_FDCWD, resolved, symlink, sizeof(symlink) - 1);
#endif
if (slen < 0)
{
return slen;
Expand Down Expand Up @@ -207,4 +212,4 @@ long realpath(const char *path, char resolved[PATH_MAX], bool resolveSymlinks)
if (resolved_len > 1 && resolved[resolved_len - 1] == '/')
resolved[resolved_len - 1] = '\0';
return (long)(resolved);
}
}

0 comments on commit b80e6d9

Please sign in to comment.