/**
* Create a file or directory that hides path below branch_rw
*/
static int do_create_whiteout(const char *path, int branch_rw, enum whiteout mode) {
DBG("%s\n", path);
char metapath[PATHLEN_MAX];
if (BUILD_PATH(metapath, METADIR, path)) RETURN(-1);
// p MUST be without path to branch prefix here! 2 x branch_rw is correct here!
// this creates e.g. branch/.unionfs/some_directory
path_create_cutlast(metapath, branch_rw, branch_rw);
char p[PATHLEN_MAX];
if (BUILD_PATH(p, uopt.branches[branch_rw].path, metapath)) RETURN(-1);
strcat(p, HIDETAG); // TODO check length
int res;
if (mode == WHITEOUT_FILE) {
res = open(p, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
if (res == -1) RETURN(-1);
res = close(res);
} else {
res = mkdir(p, S_IRWXU);
if (res)
USYSLOG(LOG_ERR, "Creating %s failed: %s\n", p, strerror(errno));
}
RETURN(res);
}
/**
* Create a file or directory that hides path below root_rw
*/
static int do_create_whiteout(const char *path, int root_rw, enum whiteout mode) {
char metapath[PATHLEN_MAX];
int res = -1;
to_root(); // whiteouts are root business
if (BUILD_PATH(metapath, METADIR, path)) {
syslog (LOG_WARNING, "%s(): Path too long\n", __func__);
goto out;
}
// p MUST be without path to branch prefix here! 2 x root_rw is correct here!
// this creates e.g. branch/.unionfs/some_directory
path_create_cutlast(metapath, root_rw, root_rw);
char p[PATHLEN_MAX];
if (BUILD_PATH(p, uopt.roots[root_rw].path, metapath, HIDETAG)) {
syslog (LOG_WARNING, "%s(): Path too long\n", __func__);
goto out;
}
if (mode == WHITEOUT_FILE) {
res = open(p, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
if (res == -1)
goto out;
res = close(res);
} else
res = mkdir(p, S_IRWXU);
out:
to_user();
return res;
}
/**
* initiate the cow-copy action
*/
int cow_cp(const char *path, int branch_ro, int branch_rw, bool copy_dir) {
DBG("%s\n", path);
// create the path to the file
path_create_cutlast(path, branch_ro, branch_rw);
char from[PATHLEN_MAX], to[PATHLEN_MAX];
if (BUILD_PATH(from, uopt.branches[branch_ro].path, path))
RETURN(-ENAMETOOLONG);
if (BUILD_PATH(to, uopt.branches[branch_rw].path, path))
RETURN(-ENAMETOOLONG);
setlocale(LC_ALL, "");
struct cow cow;
cow.uid = getuid();
// Copy the umask for explicit mode setting.
cow.umask = umask(0);
umask(cow.umask);
cow.from_path = from;
cow.to_path = to;
struct stat buf;
lstat(cow.from_path, &buf);
cow.stat = &buf;
int res;
switch (buf.st_mode & S_IFMT) {
case S_IFLNK:
res = copy_link(&cow);
break;
case S_IFDIR:
if (copy_dir) {
res = copy_directory(path, branch_ro, branch_rw);
} else {
res = path_create(path, branch_ro, branch_rw);
}
break;
case S_IFBLK:
case S_IFCHR:
res = copy_special(&cow);
break;
case S_IFIFO:
res = copy_fifo(&cow);
break;
case S_IFSOCK:
USYSLOG(LOG_WARNING, "COW of sockets not supported: %s\n", cow.from_path);
RETURN(1);
default:
res = copy_file(&cow);
}
RETURN(res);
}
/**
* initiate the cow-copy action
*/
int cow_cp(const char *path, int branch_ro, int branch_rw) {
DBG_IN();
// create the path to the file
path_create_cutlast(path, branch_ro, branch_rw);
char from[PATHLEN_MAX], to[PATHLEN_MAX];
snprintf(from, PATHLEN_MAX, "%s%s", uopt.branches[branch_ro].path, path);
snprintf(to, PATHLEN_MAX, "%s%s", uopt.branches[branch_rw].path, path);
setlocale(LC_ALL, "");
struct cow cow;
cow.uid = getuid();
// Copy the umask for explicit mode setting.
cow.umask = umask(0);
umask(cow.umask);
cow.from_path = from;
cow.to_path = to;
struct stat buf;
lstat(cow.from_path, &buf);
cow.stat = &buf;
int res;
switch (buf.st_mode & S_IFMT) {
case S_IFLNK:
res = copy_link(&cow);
break;
case S_IFDIR:
res = copy_directory(path, branch_ro, branch_rw);
break;
case S_IFBLK:
case S_IFCHR:
res = copy_special(&cow);
break;
case S_IFIFO:
res = copy_fifo(&cow);
break;
case S_IFSOCK:
usyslog(LOG_WARNING, "COW of sockets not supported: %s\n", cow.from_path);
return 1;
default:
res = copy_file(&cow);
}
return res;
}
