X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fbasic%2Fcopy.c;h=37212be228de1e2e9c7e0d6bc2abf89091b4e9ca;hp=6be7cc37a4519fb00748762af5a0dc9a4666ce82;hb=d93247127eb2e073a6d3b5bcc67bcc4048d674fe;hpb=66ecc207e203db5434610395cd04c40ae8727b58 diff --git a/src/basic/copy.c b/src/basic/copy.c index 6be7cc37a..37212be22 100644 --- a/src/basic/copy.c +++ b/src/basic/copy.c @@ -46,17 +46,38 @@ //#include "umask-util.h" //#include "xattr-util.h" -#define COPY_BUFFER_SIZE (16*1024) +#define COPY_BUFFER_SIZE (16*1024u) -int copy_bytes(int fdf, int fdt, uint64_t max_bytes, bool try_reflink) { - bool try_sendfile = true, try_splice = true; +static ssize_t try_copy_file_range(int fd_in, loff_t *off_in, + int fd_out, loff_t *off_out, + size_t len, + unsigned int flags) { + static int have = -1; + ssize_t r; + + if (have == false) + return -ENOSYS; + + r = copy_file_range(fd_in, off_in, fd_out, off_out, len, flags); + if (_unlikely_(have < 0)) + have = r >= 0 || errno != ENOSYS; + if (r >= 0) + return r; + else + return -errno; +} + +int copy_bytes(int fdf, int fdt, uint64_t max_bytes, CopyFlags copy_flags) { + bool try_cfr = true, try_sendfile = true, try_splice = true; int r; + size_t m = SSIZE_MAX; /* that is the maximum that sendfile and c_f_r accept */ assert(fdf >= 0); assert(fdt >= 0); + #if 0 /// UNNEEDED by elogind /* Try btrfs reflinks first. */ - if (try_reflink && + if ((copy_flags & COPY_REFLINK) && max_bytes == (uint64_t) -1 && lseek(fdf, 0, SEEK_CUR) == 0 && lseek(fdt, 0, SEEK_CUR) == 0) { @@ -66,57 +87,71 @@ int copy_bytes(int fdf, int fdt, uint64_t max_bytes, bool try_reflink) { return 0; /* we copied the whole thing, hence hit EOF, return 0 */ } #endif // 0 + for (;;) { - size_t m = COPY_BUFFER_SIZE; ssize_t n; if (max_bytes != (uint64_t) -1) { - if (max_bytes <= 0) return 1; /* return > 0 if we hit the max_bytes limit */ - if ((uint64_t) m > max_bytes) - m = (size_t) max_bytes; + if (m > max_bytes) + m = max_bytes; + } + + /* First try copy_file_range(), unless we already tried */ + if (try_cfr) { + n = try_copy_file_range(fdf, NULL, fdt, NULL, m, 0u); + if (n < 0) { + if (!IN_SET(n, -EINVAL, -ENOSYS, -EXDEV, -EBADF)) + return n; + + try_cfr = false; + /* use fallback below */ + } else if (n == 0) /* EOF */ + break; + else + /* Success! */ + goto next; } /* First try sendfile(), unless we already tried */ if (try_sendfile) { - n = sendfile(fdt, fdf, NULL, m); if (n < 0) { - if (errno != EINVAL && errno != ENOSYS) + if (!IN_SET(errno, EINVAL, ENOSYS)) return -errno; try_sendfile = false; /* use fallback below */ } else if (n == 0) /* EOF */ break; - else if (n > 0) + else /* Success! */ goto next; } - /* The try splice, unless we already tried */ + /* Then try splice, unless we already tried */ if (try_splice) { - n = splice(fdf, NULL, fdt, NULL, m, 0); + n = splice(fdf, NULL, fdt, NULL, m, 0); if (n < 0) { - if (errno != EINVAL && errno != ENOSYS) + if (!IN_SET(errno, EINVAL, ENOSYS)) return -errno; try_splice = false; /* use fallback below */ } else if (n == 0) /* EOF */ break; - else if (n > 0) + else /* Success! */ goto next; } /* As a fallback just copy bits by hand */ { - uint8_t buf[m]; + uint8_t buf[MIN(m, COPY_BUFFER_SIZE)]; - n = read(fdf, buf, m); + n = read(fdf, buf, sizeof buf); if (n < 0) return -errno; if (n == 0) /* EOF */ @@ -132,13 +167,27 @@ int copy_bytes(int fdf, int fdt, uint64_t max_bytes, bool try_reflink) { assert(max_bytes >= (uint64_t) n); max_bytes -= n; } + /* sendfile accepts at most SSIZE_MAX-offset bytes to copy, + * so reduce our maximum by the amount we already copied, + * but don't go below our copy buffer size, unless we are + * close the limit of bytes we are allowed to copy. */ + m = MAX(MIN(COPY_BUFFER_SIZE, max_bytes), m - n); } return 0; /* return 0 if we hit EOF earlier than the size limit */ } #if 0 /// UNNEEDED by elogind -static int fd_copy_symlink(int df, const char *from, const struct stat *st, int dt, const char *to) { +static int fd_copy_symlink( + int df, + const char *from, + const struct stat *st, + int dt, + const char *to, + uid_t override_uid, + gid_t override_gid, + CopyFlags copy_flags) { + _cleanup_free_ char *target = NULL; int r; @@ -153,13 +202,25 @@ static int fd_copy_symlink(int df, const char *from, const struct stat *st, int if (symlinkat(target, dt, to) < 0) return -errno; - if (fchownat(dt, to, st->st_uid, st->st_gid, AT_SYMLINK_NOFOLLOW) < 0) + if (fchownat(dt, to, + uid_is_valid(override_uid) ? override_uid : st->st_uid, + gid_is_valid(override_gid) ? override_gid : st->st_gid, + AT_SYMLINK_NOFOLLOW) < 0) return -errno; return 0; } -static int fd_copy_regular(int df, const char *from, const struct stat *st, int dt, const char *to) { +static int fd_copy_regular( + int df, + const char *from, + const struct stat *st, + int dt, + const char *to, + uid_t override_uid, + gid_t override_gid, + CopyFlags copy_flags) { + _cleanup_close_ int fdf = -1, fdt = -1; struct timespec ts[2]; int r, q; @@ -176,13 +237,15 @@ static int fd_copy_regular(int df, const char *from, const struct stat *st, int if (fdt < 0) return -errno; - r = copy_bytes(fdf, fdt, (uint64_t) -1, true); + r = copy_bytes(fdf, fdt, (uint64_t) -1, copy_flags); if (r < 0) { unlinkat(dt, to, 0); return r; } - if (fchown(fdt, st->st_uid, st->st_gid) < 0) + if (fchown(fdt, + uid_is_valid(override_uid) ? override_uid : st->st_uid, + gid_is_valid(override_gid) ? override_gid : st->st_gid) < 0) r = -errno; if (fchmod(fdt, st->st_mode & 07777) < 0) @@ -191,7 +254,6 @@ static int fd_copy_regular(int df, const char *from, const struct stat *st, int ts[0] = st->st_atim; ts[1] = st->st_mtim; (void) futimens(fdt, ts); - (void) copy_xattr(fdf, fdt); q = close(fdt); @@ -205,7 +267,15 @@ static int fd_copy_regular(int df, const char *from, const struct stat *st, int return r; } -static int fd_copy_fifo(int df, const char *from, const struct stat *st, int dt, const char *to) { +static int fd_copy_fifo( + int df, + const char *from, + const struct stat *st, + int dt, + const char *to, + uid_t override_uid, + gid_t override_gid, + CopyFlags copy_flags) { int r; assert(from); @@ -216,7 +286,10 @@ static int fd_copy_fifo(int df, const char *from, const struct stat *st, int dt, if (r < 0) return -errno; - if (fchownat(dt, to, st->st_uid, st->st_gid, AT_SYMLINK_NOFOLLOW) < 0) + if (fchownat(dt, to, + uid_is_valid(override_uid) ? override_uid : st->st_uid, + gid_is_valid(override_gid) ? override_gid : st->st_gid, + AT_SYMLINK_NOFOLLOW) < 0) r = -errno; if (fchmodat(dt, to, st->st_mode & 07777, 0) < 0) @@ -225,7 +298,15 @@ static int fd_copy_fifo(int df, const char *from, const struct stat *st, int dt, return r; } -static int fd_copy_node(int df, const char *from, const struct stat *st, int dt, const char *to) { +static int fd_copy_node( + int df, + const char *from, + const struct stat *st, + int dt, + const char *to, + uid_t override_uid, + gid_t override_gid, + CopyFlags copy_flags) { int r; assert(from); @@ -236,7 +317,10 @@ static int fd_copy_node(int df, const char *from, const struct stat *st, int dt, if (r < 0) return -errno; - if (fchownat(dt, to, st->st_uid, st->st_gid, AT_SYMLINK_NOFOLLOW) < 0) + if (fchownat(dt, to, + uid_is_valid(override_uid) ? override_uid : st->st_uid, + gid_is_valid(override_gid) ? override_gid : st->st_gid, + AT_SYMLINK_NOFOLLOW) < 0) r = -errno; if (fchmodat(dt, to, st->st_mode & 07777, 0) < 0) @@ -252,7 +336,9 @@ static int fd_copy_directory( int dt, const char *to, dev_t original_device, - bool merge) { + uid_t override_uid, + gid_t override_gid, + CopyFlags copy_flags) { _cleanup_close_ int fdf = -1, fdt = -1; _cleanup_closedir_ DIR *d = NULL; @@ -267,6 +353,8 @@ static int fd_copy_directory( fdf = openat(df, from, O_RDONLY|O_DIRECTORY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW); else fdf = fcntl(df, F_DUPFD_CLOEXEC, 3); + if (fdf < 0) + return -errno; d = fdopendir(fdf); if (!d) @@ -276,7 +364,7 @@ static int fd_copy_directory( r = mkdirat(dt, to, st->st_mode & 07777); if (r >= 0) created = true; - else if (errno == EEXIST && merge) + else if (errno == EEXIST && (copy_flags & COPY_MERGE)) created = false; else return -errno; @@ -287,27 +375,11 @@ static int fd_copy_directory( r = 0; - if (created) { - struct timespec ut[2] = { - st->st_atim, - st->st_mtim - }; - - if (fchown(fdt, st->st_uid, st->st_gid) < 0) - r = -errno; - - if (fchmod(fdt, st->st_mode & 07777) < 0) - r = -errno; - - (void) futimens(fdt, ut); - (void) copy_xattr(dirfd(d), fdt); - } - FOREACH_DIRENT_ALL(de, d, return -errno) { struct stat buf; int q; - if (STR_IN_SET(de->d_name, ".", "..")) + if (dot_or_dot_dot(de->d_name)) continue; if (fstatat(dirfd(d), de->d_name, &buf, AT_SYMLINK_NOFOLLOW) < 0) { @@ -319,29 +391,47 @@ static int fd_copy_directory( continue; if (S_ISREG(buf.st_mode)) - q = fd_copy_regular(dirfd(d), de->d_name, &buf, fdt, de->d_name); + q = fd_copy_regular(dirfd(d), de->d_name, &buf, fdt, de->d_name, override_uid, override_gid, copy_flags); else if (S_ISDIR(buf.st_mode)) - q = fd_copy_directory(dirfd(d), de->d_name, &buf, fdt, de->d_name, original_device, merge); + q = fd_copy_directory(dirfd(d), de->d_name, &buf, fdt, de->d_name, original_device, override_uid, override_gid, copy_flags); else if (S_ISLNK(buf.st_mode)) - q = fd_copy_symlink(dirfd(d), de->d_name, &buf, fdt, de->d_name); + q = fd_copy_symlink(dirfd(d), de->d_name, &buf, fdt, de->d_name, override_uid, override_gid, copy_flags); else if (S_ISFIFO(buf.st_mode)) - q = fd_copy_fifo(dirfd(d), de->d_name, &buf, fdt, de->d_name); - else if (S_ISBLK(buf.st_mode) || S_ISCHR(buf.st_mode)) - q = fd_copy_node(dirfd(d), de->d_name, &buf, fdt, de->d_name); + q = fd_copy_fifo(dirfd(d), de->d_name, &buf, fdt, de->d_name, override_uid, override_gid, copy_flags); + else if (S_ISBLK(buf.st_mode) || S_ISCHR(buf.st_mode) || S_ISSOCK(buf.st_mode)) + q = fd_copy_node(dirfd(d), de->d_name, &buf, fdt, de->d_name, override_uid, override_gid, copy_flags); else q = -EOPNOTSUPP; - if (q == -EEXIST && merge) + if (q == -EEXIST && (copy_flags & COPY_MERGE)) q = 0; if (q < 0) r = q; } + if (created) { + struct timespec ut[2] = { + st->st_atim, + st->st_mtim + }; + + if (fchown(fdt, + uid_is_valid(override_uid) ? override_uid : st->st_uid, + gid_is_valid(override_gid) ? override_gid : st->st_gid) < 0) + r = -errno; + + if (fchmod(fdt, st->st_mode & 07777) < 0) + r = -errno; + + (void) copy_xattr(dirfd(d), fdt); + (void) futimens(fdt, ut); + } + return r; } -int copy_tree_at(int fdf, const char *from, int fdt, const char *to, bool merge) { +int copy_tree_at(int fdf, const char *from, int fdt, const char *to, uid_t override_uid, gid_t override_gid, CopyFlags copy_flags) { struct stat st; assert(from); @@ -351,25 +441,24 @@ int copy_tree_at(int fdf, const char *from, int fdt, const char *to, bool merge) return -errno; if (S_ISREG(st.st_mode)) - return fd_copy_regular(fdf, from, &st, fdt, to); + return fd_copy_regular(fdf, from, &st, fdt, to, override_uid, override_gid, copy_flags); else if (S_ISDIR(st.st_mode)) - return fd_copy_directory(fdf, from, &st, fdt, to, st.st_dev, merge); + return fd_copy_directory(fdf, from, &st, fdt, to, st.st_dev, override_uid, override_gid, copy_flags); else if (S_ISLNK(st.st_mode)) - return fd_copy_symlink(fdf, from, &st, fdt, to); + return fd_copy_symlink(fdf, from, &st, fdt, to, override_uid, override_gid, copy_flags); else if (S_ISFIFO(st.st_mode)) - return fd_copy_fifo(fdf, from, &st, fdt, to); - else if (S_ISBLK(st.st_mode) || S_ISCHR(st.st_mode)) - return fd_copy_node(fdf, from, &st, fdt, to); + return fd_copy_fifo(fdf, from, &st, fdt, to, override_uid, override_gid, copy_flags); + else if (S_ISBLK(st.st_mode) || S_ISCHR(st.st_mode) || S_ISSOCK(st.st_mode)) + return fd_copy_node(fdf, from, &st, fdt, to, override_uid, override_gid, copy_flags); else return -EOPNOTSUPP; } -int copy_tree(const char *from, const char *to, bool merge) { - return copy_tree_at(AT_FDCWD, from, AT_FDCWD, to, merge); +int copy_tree(const char *from, const char *to, uid_t override_uid, gid_t override_gid, CopyFlags copy_flags) { + return copy_tree_at(AT_FDCWD, from, AT_FDCWD, to, override_uid, override_gid, copy_flags); } -int copy_directory_fd(int dirfd, const char *to, bool merge) { - +int copy_directory_fd(int dirfd, const char *to, CopyFlags copy_flags) { struct stat st; assert(dirfd >= 0); @@ -381,10 +470,25 @@ int copy_directory_fd(int dirfd, const char *to, bool merge) { if (!S_ISDIR(st.st_mode)) return -ENOTDIR; - return fd_copy_directory(dirfd, NULL, &st, AT_FDCWD, to, st.st_dev, merge); + return fd_copy_directory(dirfd, NULL, &st, AT_FDCWD, to, st.st_dev, UID_INVALID, GID_INVALID, copy_flags); +} + +int copy_directory(const char *from, const char *to, CopyFlags copy_flags) { + struct stat st; + + assert(from); + assert(to); + + if (lstat(from, &st) < 0) + return -errno; + + if (!S_ISDIR(st.st_mode)) + return -ENOTDIR; + + return fd_copy_directory(AT_FDCWD, from, &st, AT_FDCWD, to, st.st_dev, UID_INVALID, GID_INVALID, copy_flags); } -int copy_file_fd(const char *from, int fdt, bool try_reflink) { +int copy_file_fd(const char *from, int fdt, CopyFlags copy_flags) { _cleanup_close_ int fdf = -1; int r; @@ -395,7 +499,7 @@ int copy_file_fd(const char *from, int fdt, bool try_reflink) { if (fdf < 0) return -errno; - r = copy_bytes(fdf, fdt, (uint64_t) -1, try_reflink); + r = copy_bytes(fdf, fdt, (uint64_t) -1, copy_flags); (void) copy_times(fdf, fdt); (void) copy_xattr(fdf, fdt); @@ -403,7 +507,7 @@ int copy_file_fd(const char *from, int fdt, bool try_reflink) { return r; } -int copy_file(const char *from, const char *to, int flags, mode_t mode, unsigned chattr_flags) { +int copy_file(const char *from, const char *to, int flags, mode_t mode, unsigned chattr_flags, CopyFlags copy_flags) { int fdt = -1, r; assert(from); @@ -418,7 +522,7 @@ int copy_file(const char *from, const char *to, int flags, mode_t mode, unsigned if (chattr_flags != 0) (void) chattr_fd(fdt, chattr_flags, (unsigned) -1); - r = copy_file_fd(from, fdt, true); + r = copy_file_fd(from, fdt, copy_flags); if (r < 0) { close(fdt); unlink(to); @@ -433,7 +537,7 @@ int copy_file(const char *from, const char *to, int flags, mode_t mode, unsigned return 0; } -int copy_file_atomic(const char *from, const char *to, mode_t mode, bool replace, unsigned chattr_flags) { +int copy_file_atomic(const char *from, const char *to, mode_t mode, unsigned chattr_flags, CopyFlags copy_flags) { _cleanup_free_ char *t = NULL; int r; @@ -444,18 +548,18 @@ int copy_file_atomic(const char *from, const char *to, mode_t mode, bool replace if (r < 0) return r; - r = copy_file(from, t, O_NOFOLLOW|O_EXCL, mode, chattr_flags); + r = copy_file(from, t, O_NOFOLLOW|O_EXCL, mode, chattr_flags, copy_flags); if (r < 0) return r; - if (replace) { + if (copy_flags & COPY_REPLACE) { r = renameat(AT_FDCWD, t, AT_FDCWD, to); if (r < 0) r = -errno; } else r = rename_noreplace(AT_FDCWD, t, AT_FDCWD, to); if (r < 0) { - (void) unlink_noerrno(t); + (void) unlink(t); return r; }