/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** This file is part of systemd. Copyright 2010-2012 Lennart Poettering systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see <http://www.gnu.org/licenses/>. ***/ #include <assert.h> #include <string.h> #include <unistd.h> #include <errno.h> #include <stdlib.h> #include <signal.h> #include <stdio.h> #include <fcntl.h> #include <dirent.h> #include <sys/statvfs.h> #include "macro.h" #include "util.h" #include "log.h" #include "strv.h" #include "path-util.h" bool path_is_absolute(const char *p) { return p[0] == '/'; } bool is_path(const char *p) { return !!strchr(p, '/'); } char *path_get_file_name(const char *p) { char *r; assert(p); if ((r = strrchr(p, '/'))) return r + 1; return (char*) p; } int path_get_parent(const char *path, char **_r) { const char *e, *a = NULL, *b = NULL, *p; char *r; bool slash = false; assert(path); assert(_r); if (!*path) return -EINVAL; for (e = path; *e; e++) { if (!slash && *e == '/') { a = b; b = e; slash = true; } else if (slash && *e != '/') slash = false; } if (*(e-1) == '/') p = a; else p = b; if (!p) return -EINVAL; if (p == path) r = strdup("/"); else r = strndup(path, p-path); if (!r) return -ENOMEM; *_r = r; return 0; } char **path_split_and_make_absolute(const char *p) { char **l; assert(p); if (!(l = strv_split(p, ":"))) return NULL; if (!path_strv_make_absolute_cwd(l)) { strv_free(l); return NULL; } return l; } char *path_make_absolute(const char *p, const char *prefix) { assert(p); /* Makes every item in the list an absolute path by prepending * the prefix, if specified and necessary */ if (path_is_absolute(p) || !prefix) return strdup(p); return strjoin(prefix, "/", p, NULL); } char *path_make_absolute_cwd(const char *p) { char *cwd, *r; assert(p); /* Similar to path_make_absolute(), but prefixes with the * current working directory. */ if (path_is_absolute(p)) return strdup(p); if (!(cwd = get_current_dir_name())) return NULL; r = path_make_absolute(p, cwd); free(cwd); return r; } char **path_strv_make_absolute_cwd(char **l) { char **s; /* Goes through every item in the string list and makes it * absolute. This works in place and won't rollback any * changes on failure. */ STRV_FOREACH(s, l) { char *t; if (!(t = path_make_absolute_cwd(*s))) return NULL; free(*s); *s = t; } return l; } char **path_strv_canonicalize(char **l) { char **s; unsigned k = 0; bool enomem = false; if (strv_isempty(l)) return l; /* Goes through every item in the string list and canonicalize * the path. This works in place and won't rollback any * changes on failure. */ STRV_FOREACH(s, l) { char *t, *u; t = path_make_absolute_cwd(*s); free(*s); if (!t) { enomem = true; continue; } errno = 0; u = canonicalize_file_name(t); free(t); if (!u) { if (errno == ENOMEM || !errno) enomem = true; continue; } l[k++] = u; } l[k] = NULL; if (enomem) return NULL; return l; } char **path_strv_remove_empty(char **l) { char **f, **t; if (!l) return NULL; for (f = t = l; *f; f++) { if (dir_is_empty(*f) > 0) { free(*f); continue; } *(t++) = *f; } *t = NULL; return l; } char *path_kill_slashes(char *path) { char *f, *t; bool slash = false; /* Removes redundant inner and trailing slashes. Modifies the * passed string in-place. * * ///foo///bar/ becomes /foo/bar */ for (f = path, t = path; *f; f++) { if (*f == '/') { slash = true; continue; } if (slash) { slash = false; *(t++) = '/'; } *(t++) = *f; } /* Special rule, if we are talking of the root directory, a trailing slash is good */ if (t == path && slash) *(t++) = '/'; *t = 0; return path; } bool path_startswith(const char *path, const char *prefix) { assert(path); assert(prefix); if ((path[0] == '/') != (prefix[0] == '/')) return false; for (;;) { size_t a, b; path += strspn(path, "/"); prefix += strspn(prefix, "/"); if (*prefix == 0) return true; if (*path == 0) return false; a = strcspn(path, "/"); b = strcspn(prefix, "/"); if (a != b) return false; if (memcmp(path, prefix, a) != 0) return false; path += a; prefix += b; } } bool path_equal(const char *a, const char *b) { assert(a); assert(b); if ((a[0] == '/') != (b[0] == '/')) return false; for (;;) { size_t j, k; a += strspn(a, "/"); b += strspn(b, "/"); if (*a == 0 && *b == 0) return true; if (*a == 0 || *b == 0) return false; j = strcspn(a, "/"); k = strcspn(b, "/"); if (j != k) return false; if (memcmp(a, b, j) != 0) return false; a += j; b += k; } } int path_is_mount_point(const char *t, bool allow_symlink) { struct stat a, b; char *parent; int r; if (allow_symlink) r = stat(t, &a); else r = lstat(t, &a); if (r < 0) { if (errno == ENOENT) return 0; return -errno; } r = path_get_parent(t, &parent); if (r < 0) return r; r = lstat(parent, &b); free(parent); if (r < 0) return -errno; return a.st_dev != b.st_dev; } int path_is_read_only_fs(const char *path) { struct statvfs st; assert(path); if (statvfs(path, &st) < 0) return -errno; return !!(st.f_flag & ST_RDONLY); }