/* SPDX-License-Identifier: LGPL-2.1+ */

#include <errno.h>

#include <stdbool.h>

#include <string.h>

#include <sys/stat.h>

#include "alloc-util.h"

#include "format-util.h"

#include "fs-util.h"

#include "macro.h"

#include "mkdir.h"

#include "path-util.h"

#include "stat-util.h"

#include "stdio-util.h"

#include "user-util.h"

int mkdir_safe_internal(const char *path, mode_t mode, uid_t uid, gid_t gid, MkdirFlags flags, mkdir_func_t _mkdir) {

        struct stat st;

        int r;

        assert(_mkdir != mkdir);

        if (_mkdir(path, mode) >= 0) {

                r = chmod_and_chown(path, mode, uid, gid);

                if (r < 0)

                        return r;

        }

        if (lstat(path, &st) < 0)

                return -errno;

        if ((flags & MKDIR_FOLLOW_SYMLINK) && S_ISLNK(st.st_mode)) {

                _cleanup_free_ char *p = NULL;

                r = chase_symlinks(path, NULL, CHASE_NONEXISTENT, &p);

                if (r < 0)

                        return r;

                if (r == 0)

                        return mkdir_safe_internal(p, mode, uid, gid,

                                                   flags & ~MKDIR_FOLLOW_SYMLINK,

                                                   _mkdir);

                if (lstat(p, &st) < 0)

                        return -errno;

        }

        if (!S_ISDIR(st.st_mode)) {

                log_full(flags & MKDIR_WARN_MODE ? LOG_WARNING : LOG_DEBUG,

                         "Path \"%s\" already exists and is not a directory, refusing.", path);

                return -ENOTDIR;

        }

        if ((st.st_mode & 0007) > (mode & 0007) ||

            (st.st_mode & 0070) > (mode & 0070) ||

            (st.st_mode & 0700) > (mode & 0700)) {

                log_full(flags & MKDIR_WARN_MODE ? LOG_WARNING : LOG_DEBUG,

                         "Directory \"%s\" already exists, but has mode %04o that is too permissive (%04o was requested), refusing.",

                         path, st.st_mode & 0777, mode);

                return -EEXIST;

        }

        if ((uid != UID_INVALID && st.st_uid != uid) ||

            (gid != GID_INVALID && st.st_gid != gid)) {

                char u[DECIMAL_STR_MAX(uid_t)] = "-", g[DECIMAL_STR_MAX(gid_t)] = "-";

                if (uid != UID_INVALID)

                        xsprintf(u, UID_FMT, uid);

                if (gid != UID_INVALID)

                        xsprintf(g, GID_FMT, gid);

                log_full(flags & MKDIR_WARN_MODE ? LOG_WARNING : LOG_DEBUG,

                         "Directory \"%s\" already exists, but is owned by "UID_FMT":"GID_FMT" (%s:%s was requested), refusing.",

                         path, st.st_uid, st.st_gid, u, g);

                return -EEXIST;

        }

        return 0;

}

int mkdir_errno_wrapper(const char *pathname, mode_t mode) {

        if (mkdir(pathname, mode) < 0)

                return -errno;

        return 0;

}

int mkdirat_errno_wrapper(int dirfd, const char *pathname, mode_t mode) {

        if (mkdirat(dirfd, pathname, mode) < 0)

                return -errno;

        return 0;

}

int mkdir_safe(const char *path, mode_t mode, uid_t uid, gid_t gid, MkdirFlags flags) {

        return mkdir_safe_internal(path, mode, uid, gid, flags, mkdir_errno_wrapper);

}

int mkdir_parents_internal(const char *prefix, const char *path, mode_t mode, mkdir_func_t _mkdir) {

        const char *p, *e;

        int r;

        assert(path);

        assert(_mkdir != mkdir);

        if (prefix && !path_startswith(path, prefix))

                return -ENOTDIR;

        /* return immediately if directory exists */

        e = strrchr(path, '/');

        if (!e)

                return -EINVAL;

        if (e == path)

                return 0;

        p = strndupa(path, e - path);

        r = is_dir(p, true);

        if (r > 0)

                return 0;

        if (r == 0)

                return -ENOTDIR;

        /* create every parent directory in the path, except the last component */

        p = path + strspn(path, "/");

        for (;;) {

                char t[strlen(path) + 1];

                e = p + strcspn(p, "/");

                p = e + strspn(e, "/");

                /* Is this the last component? If so, then we're done */

                if (*p == 0)

                        return 0;

                memcpy(t, path, e - path);

                t[e-path] = 0;

                if (prefix && path_startswith(prefix, t))

                        continue;

                r = _mkdir(t, mode);

                if (r < 0 && r != -EEXIST)

                        return r;

        }

}

int mkdir_parents(const char *path, mode_t mode) {

        return mkdir_parents_internal(NULL, path, mode, mkdir_errno_wrapper);

}

int mkdir_p_internal(const char *prefix, const char *path, mode_t mode, mkdir_func_t _mkdir) {

        int r;

        /* Like mkdir -p */

        assert(_mkdir != mkdir);

        r = mkdir_parents_internal(prefix, path, mode, _mkdir);

        if (r < 0)

                return r;

        r = _mkdir(path, mode);

        if (r < 0 && (r != -EEXIST || is_dir(path, true) <= 0))

                return r;

        return 0;

}

int mkdir_p(const char *path, mode_t mode) {

        return mkdir_p_internal(NULL, path, mode, mkdir_errno_wrapper);

}