X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fbasic%2Fpath-util.c;h=5f4252f48cfe7d86ece820d592ed21dd336e05bd;hp=3998fc98a8f87b5d77b1da917a6154369ec03a15;hb=6b05aab633fa55aa3070f186869d8fa219be2f38;hpb=d2338db3145922b1dfcb3b458e5bce2568a9347a
diff --git a/src/basic/path-util.c b/src/basic/path-util.c
index 3998fc98a..5f4252f48 100644
--- a/src/basic/path-util.c
+++ b/src/basic/path-util.c
@@ -1,5 +1,3 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
/***
This file is part of systemd.
@@ -19,21 +17,31 @@
along with systemd; If not, see .
***/
-#include
-#include
#include
-#include
+#include
#include
-#include
-#include
+#include
+#include
+#include
+#include
-#include "macro.h"
-#include "util.h"
+/* When we include libgen.h because we need dirname() we immediately
+ * undefine basename() since libgen.h defines it as a macro to the
+ * POSIX version which is really broken. We prefer GNU basename(). */
+#include
+#undef basename
+
+#include "alloc-util.h"
+#include "extract-word.h"
+#include "fs-util.h"
#include "log.h"
-#include "strv.h"
-#include "path-util.h"
+#include "macro.h"
#include "missing.h"
-#include "fileio.h"
+#include "path-util.h"
+#include "stat-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "time-util.h"
bool path_is_absolute(const char *p) {
return p[0] == '/';
@@ -43,65 +51,27 @@ bool is_path(const char *p) {
return !!strchr(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;
-}
-
-/// UNNEEDED by elogind
-#if 0
-char **path_split_and_make_absolute(const char *p) {
+#if 0 /// UNNEEDED by elogind
+int path_split_and_make_absolute(const char *p, char ***ret) {
char **l;
+ int r;
+
assert(p);
+ assert(ret);
l = strv_split(p, ":");
if (!l)
- return NULL;
+ return -ENOMEM;
- if (!path_strv_make_absolute_cwd(l)) {
+ r = path_strv_make_absolute_cwd(l);
+ if (r < 0) {
strv_free(l);
- return NULL;
+ return r;
}
- return l;
+ *ret = l;
+ return r;
}
-#endif // 0
char *path_make_absolute(const char *p, const char *prefix) {
assert(p);
@@ -114,27 +84,36 @@ char *path_make_absolute(const char *p, const char *prefix) {
return strjoin(prefix, "/", p, NULL);
}
+#endif // 0
-char *path_make_absolute_cwd(const char *p) {
- _cleanup_free_ char *cwd = NULL;
+int path_make_absolute_cwd(const char *p, char **ret) {
+ char *c;
assert(p);
+ assert(ret);
/* Similar to path_make_absolute(), but prefixes with the
* current working directory. */
if (path_is_absolute(p))
- return strdup(p);
+ c = strdup(p);
+ else {
+ _cleanup_free_ char *cwd = NULL;
cwd = get_current_dir_name();
if (!cwd)
- return NULL;
+ return -errno;
- return strjoin(cwd, "/", p, NULL);
+ c = strjoin(cwd, "/", p, NULL);
+ }
+ if (!c)
+ return -ENOMEM;
+
+ *ret = c;
+ return 0;
}
-/// UNNEEDED by elogind
-#if 0
+#if 0 /// UNNEEDED by elogind
int path_make_relative(const char *from_dir, const char *to_path, char **_r) {
char *r, *p;
unsigned n_parents;
@@ -220,8 +199,9 @@ int path_make_relative(const char *from_dir, const char *to_path, char **_r) {
return 0;
}
-char **path_strv_make_absolute_cwd(char **l) {
+int path_strv_make_absolute_cwd(char **l) {
char **s;
+ int r;
/* Goes through every item in the string list and makes it
* absolute. This works in place and won't rollback any
@@ -230,15 +210,15 @@ char **path_strv_make_absolute_cwd(char **l) {
STRV_FOREACH(s, l) {
char *t;
- t = path_make_absolute_cwd(*s);
- if (!t)
- return NULL;
+ r = path_make_absolute_cwd(*s, &t);
+ if (r < 0)
+ return r;
free(*s);
*s = t;
}
- return l;
+ return 0;
}
#endif // 0
@@ -417,7 +397,7 @@ int path_compare(const char *a, const char *b) {
* Which one is sorted before the other does not really matter.
* Here a relative path is ordered before an absolute path. */
d = (a[0] == '/') - (b[0] == '/');
- if (d)
+ if (d != 0)
return d;
for (;;) {
@@ -440,12 +420,12 @@ int path_compare(const char *a, const char *b) {
/* Alphabetical sort: "/foo/aaa" before "/foo/b" */
d = memcmp(a, b, MIN(j, k));
- if (d)
+ if (d != 0)
return (d > 0) - (d < 0); /* sign of d */
/* Sort "/foo/a" before "/foo/aaa" */
d = (j > k) - (j < k); /* sign of (j - k) */
- if (d)
+ if (d != 0)
return d;
a += j;
@@ -457,12 +437,11 @@ bool path_equal(const char *a, const char *b) {
return path_compare(a, b) == 0;
}
-/// UNNEEDED by elogind
-#if 0
bool path_equal_or_files_same(const char *a, const char *b) {
return path_equal(a, b) || files_same(a, b) > 0;
}
+#if 0 /// UNNEEDED by elogind
char* path_join(const char *root, const char *path, const char *rest) {
assert(path);
@@ -478,298 +457,67 @@ char* path_join(const char *root, const char *path, const char *rest) {
rest && rest[0] == '/' ? rest+1 : rest,
NULL);
}
-#endif // 0
-
-static int fd_fdinfo_mnt_id(int fd, const char *filename, int flags, int *mnt_id) {
- char path[strlen("/proc/self/fdinfo/") + DECIMAL_STR_MAX(int)];
- _cleanup_free_ char *fdinfo = NULL;
- _cleanup_close_ int subfd = -1;
- char *p;
- int r;
-
- if ((flags & AT_EMPTY_PATH) && isempty(filename))
- xsprintf(path, "/proc/self/fdinfo/%i", fd);
- else {
- subfd = openat(fd, filename, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_PATH);
- if (subfd < 0)
- return -errno;
-
- xsprintf(path, "/proc/self/fdinfo/%i", subfd);
- }
-
- r = read_full_file(path, &fdinfo, NULL);
- if (r == -ENOENT) /* The fdinfo directory is a relatively new addition */
- return -EOPNOTSUPP;
- if (r < 0)
- return -errno;
-
- p = startswith(fdinfo, "mnt_id:");
- if (!p) {
- p = strstr(fdinfo, "\nmnt_id:");
- if (!p) /* The mnt_id field is a relatively new addition */
- return -EOPNOTSUPP;
-
- p += 8;
- }
-
- p += strspn(p, WHITESPACE);
- p[strcspn(p, WHITESPACE)] = 0;
-
- return safe_atoi(p, mnt_id);
-}
-
-int fd_is_mount_point(int fd, const char *filename, int flags) {
- union file_handle_union h = FILE_HANDLE_INIT, h_parent = FILE_HANDLE_INIT;
- int mount_id = -1, mount_id_parent = -1;
- bool nosupp = false, check_st_dev = true;
- struct stat a, b;
- int r;
-
- assert(fd >= 0);
- assert(filename);
-
- /* First we will try the name_to_handle_at() syscall, which
- * tells us the mount id and an opaque file "handle". It is
- * not supported everywhere though (kernel compile-time
- * option, not all file systems are hooked up). If it works
- * the mount id is usually good enough to tell us whether
- * something is a mount point.
- *
- * If that didn't work we will try to read the mount id from
- * /proc/self/fdinfo/. This is almost as good as
- * name_to_handle_at(), however, does not return the
- * opaque file handle. The opaque file handle is pretty useful
- * to detect the root directory, which we should always
- * consider a mount point. Hence we use this only as
- * fallback. Exporting the mnt_id in fdinfo is a pretty recent
- * kernel addition.
- *
- * As last fallback we do traditional fstat() based st_dev
- * comparisons. This is how things were traditionally done,
- * but unionfs breaks breaks this since it exposes file
- * systems with a variety of st_dev reported. Also, btrfs
- * subvolumes have different st_dev, even though they aren't
- * real mounts of their own. */
-
- r = name_to_handle_at(fd, filename, &h.handle, &mount_id, flags);
- if (r < 0) {
- if (errno == ENOSYS)
- /* This kernel does not support name_to_handle_at()
- * fall back to simpler logic. */
- goto fallback_fdinfo;
- else if (errno == EOPNOTSUPP)
- /* This kernel or file system does not support
- * name_to_handle_at(), hence let's see if the
- * upper fs supports it (in which case it is a
- * mount point), otherwise fallback to the
- * traditional stat() logic */
- nosupp = true;
- else
- return -errno;
- }
-
- r = name_to_handle_at(fd, "", &h_parent.handle, &mount_id_parent, AT_EMPTY_PATH);
- if (r < 0) {
- if (errno == EOPNOTSUPP) {
- if (nosupp)
- /* Neither parent nor child do name_to_handle_at()?
- We have no choice but to fall back. */
- goto fallback_fdinfo;
- else
- /* The parent can't do name_to_handle_at() but the
- * directory we are interested in can?
- * If so, it must be a mount point. */
- return 1;
- } else
- return -errno;
- }
-
- /* The parent can do name_to_handle_at() but the
- * directory we are interested in can't? If so, it
- * must be a mount point. */
- if (nosupp)
- return 1;
-
- /* If the file handle for the directory we are
- * interested in and its parent are identical, we
- * assume this is the root directory, which is a mount
- * point. */
-
- if (h.handle.handle_bytes == h_parent.handle.handle_bytes &&
- h.handle.handle_type == h_parent.handle.handle_type &&
- memcmp(h.handle.f_handle, h_parent.handle.f_handle, h.handle.handle_bytes) == 0)
- return 1;
-
- return mount_id != mount_id_parent;
-
-fallback_fdinfo:
- r = fd_fdinfo_mnt_id(fd, filename, flags, &mount_id);
- if (r == -EOPNOTSUPP)
- goto fallback_fstat;
- if (r < 0)
- return r;
-
- r = fd_fdinfo_mnt_id(fd, "", AT_EMPTY_PATH, &mount_id_parent);
- if (r < 0)
- return r;
-
- if (mount_id != mount_id_parent)
- return 1;
-
- /* Hmm, so, the mount ids are the same. This leaves one
- * special case though for the root file system. For that,
- * let's see if the parent directory has the same inode as we
- * are interested in. Hence, let's also do fstat() checks now,
- * too, but avoid the st_dev comparisons, since they aren't
- * that useful on unionfs mounts. */
- check_st_dev = false;
-
-fallback_fstat:
- /* yay for fstatat() taking a different set of flags than the other
- * _at() above */
- if (flags & AT_SYMLINK_FOLLOW)
- flags &= ~AT_SYMLINK_FOLLOW;
- else
- flags |= AT_SYMLINK_NOFOLLOW;
- if (fstatat(fd, filename, &a, flags) < 0)
- return -errno;
-
- if (fstatat(fd, "", &b, AT_EMPTY_PATH) < 0)
- return -errno;
-
- /* A directory with same device and inode as its parent? Must
- * be the root directory */
- if (a.st_dev == b.st_dev &&
- a.st_ino == b.st_ino)
- return 1;
-
- return check_st_dev && (a.st_dev != b.st_dev);
-}
-/* flags can be AT_SYMLINK_FOLLOW or 0 */
-int path_is_mount_point(const char *t, int flags) {
- _cleanup_close_ int fd = -1;
- _cleanup_free_ char *canonical = NULL, *parent = NULL;
- int r;
-
- assert(t);
-
- if (path_equal(t, "/"))
- return 1;
-
- /* we need to resolve symlinks manually, we can't just rely on
- * fd_is_mount_point() to do that for us; if we have a structure like
- * /bin -> /usr/bin/ and /usr is a mount point, then the parent that we
- * look at needs to be /usr, not /. */
- if (flags & AT_SYMLINK_FOLLOW) {
- canonical = canonicalize_file_name(t);
- if (!canonical)
- return -errno;
-
- t = canonical;
- }
+int find_binary(const char *name, char **ret) {
+ int last_error, r;
+ const char *p;
- r = path_get_parent(t, &parent);
- if (r < 0)
- return r;
-
- fd = openat(AT_FDCWD, parent, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_PATH);
- if (fd < 0)
- return -errno;
-
- return fd_is_mount_point(fd, basename(t), flags);
-}
-
-int path_is_read_only_fs(const char *path) {
- struct statvfs st;
-
- assert(path);
-
- if (statvfs(path, &st) < 0)
- return -errno;
-
- if (st.f_flag & ST_RDONLY)
- return true;
-
- /* On NFS, statvfs() might not reflect whether we can actually
- * write to the remote share. Let's try again with
- * access(W_OK) which is more reliable, at least sometimes. */
- if (access(path, W_OK) < 0 && errno == EROFS)
- return true;
-
- return false;
-}
-
-/// UNNEEDED by elogind
-#if 0
-int path_is_os_tree(const char *path) {
- char *p;
- int r;
-
- /* We use /usr/lib/os-release as flag file if something is an OS */
- p = strjoina(path, "/usr/lib/os-release");
- r = access(p, F_OK);
-
- if (r >= 0)
- return 1;
-
- /* Also check for the old location in /etc, just in case. */
- p = strjoina(path, "/etc/os-release");
- r = access(p, F_OK);
-
- return r >= 0;
-}
-
-int find_binary(const char *name, bool local, char **filename) {
assert(name);
if (is_path(name)) {
- if (local && access(name, X_OK) < 0)
+ if (access(name, X_OK) < 0)
return -errno;
- if (filename) {
- char *p;
-
- p = path_make_absolute_cwd(name);
- if (!p)
- return -ENOMEM;
-
- *filename = p;
+ if (ret) {
+ r = path_make_absolute_cwd(name, ret);
+ if (r < 0)
+ return r;
}
return 0;
- } else {
- const char *path;
- const char *word, *state;
- size_t l;
+ }
/**
* Plain getenv, not secure_getenv, because we want
* to actually allow the user to pick the binary.
*/
- path = getenv("PATH");
- if (!path)
- path = DEFAULT_PATH;
+ p = getenv("PATH");
+ if (!p)
+ p = DEFAULT_PATH;
- FOREACH_WORD_SEPARATOR(word, l, path, ":", state) {
- _cleanup_free_ char *p = NULL;
+ last_error = -ENOENT;
- if (asprintf(&p, "%.*s/%s", (int) l, word, name) < 0)
- return -ENOMEM;
+ for (;;) {
+ _cleanup_free_ char *j = NULL, *element = NULL;
+
+ r = extract_first_word(&p, &element, ":", EXTRACT_RELAX|EXTRACT_DONT_COALESCE_SEPARATORS);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ break;
- if (access(p, X_OK) < 0)
+ if (!path_is_absolute(element))
continue;
- if (filename) {
- *filename = path_kill_slashes(p);
- p = NULL;
+ j = strjoin(element, "/", name, NULL);
+ if (!j)
+ return -ENOMEM;
+
+ if (access(j, X_OK) >= 0) {
+ /* Found it! */
+
+ if (ret) {
+ *ret = path_kill_slashes(j);
+ j = NULL;
}
return 0;
}
- return -ENOENT;
+ last_error = -errno;
}
+
+ return last_error;
}
bool paths_check_timestamp(const char* const* paths, usec_t *timestamp, bool update) {
@@ -807,14 +555,13 @@ bool paths_check_timestamp(const char* const* paths, usec_t *timestamp, bool upd
return changed;
}
-int fsck_exists(const char *fstype) {
+static int binary_is_good(const char *binary) {
_cleanup_free_ char *p = NULL, *d = NULL;
- const char *checker;
int r;
- checker = strjoina("fsck.", fstype);
-
- r = find_binary(checker, true, &p);
+ r = find_binary(binary, &p);
+ if (r == -ENOENT)
+ return 0;
if (r < 0)
return r;
@@ -822,13 +569,39 @@ int fsck_exists(const char *fstype) {
* fsck */
r = readlink_malloc(p, &d);
- if (r >= 0 &&
- (path_equal(d, "/bin/true") ||
- path_equal(d, "/usr/bin/true") ||
- path_equal(d, "/dev/null")))
- return -ENOENT;
+ if (r == -EINVAL) /* not a symlink */
+ return 1;
+ if (r < 0)
+ return r;
- return 0;
+ return !PATH_IN_SET(d, "true"
+ "/bin/true",
+ "/usr/bin/true",
+ "/dev/null");
+}
+
+int fsck_exists(const char *fstype) {
+ const char *checker;
+
+ assert(fstype);
+
+ if (streq(fstype, "auto"))
+ return -EINVAL;
+
+ checker = strjoina("fsck.", fstype);
+ return binary_is_good(checker);
+}
+
+int mkfs_exists(const char *fstype) {
+ const char *mkfs;
+
+ assert(fstype);
+
+ if (streq(fstype, "auto"))
+ return -EINVAL;
+
+ mkfs = strjoina("mkfs.", fstype);
+ return binary_is_good(mkfs);
}
char *prefix_root(const char *root, const char *path) {
@@ -864,4 +637,172 @@ char *prefix_root(const char *root, const char *path) {
strcpy(p, path);
return n;
}
+
+int parse_path_argument_and_warn(const char *path, bool suppress_root, char **arg) {
+ char *p;
+ int r;
+
+ /*
+ * This function is intended to be used in command line
+ * parsers, to handle paths that are passed in. It makes the
+ * path absolute, and reduces it to NULL if omitted or
+ * root (the latter optionally).
+ *
+ * NOTE THAT THIS WILL FREE THE PREVIOUS ARGUMENT POINTER ON
+ * SUCCESS! Hence, do not pass in uninitialized pointers.
+ */
+
+ if (isempty(path)) {
+ *arg = mfree(*arg);
+ return 0;
+ }
+
+ r = path_make_absolute_cwd(path, &p);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse path \"%s\" and make it absolute: %m", path);
+
+ path_kill_slashes(p);
+ if (suppress_root && path_equal(p, "/"))
+ p = mfree(p);
+
+ free(*arg);
+ *arg = p;
+ return 0;
+}
+#endif // 0
+
+char* dirname_malloc(const char *path) {
+ char *d, *dir, *dir2;
+
+ assert(path);
+
+ d = strdup(path);
+ if (!d)
+ return NULL;
+
+ dir = dirname(d);
+ assert(dir);
+
+ if (dir == d)
+ return d;
+
+ dir2 = strdup(dir);
+ free(d);
+
+ return dir2;
+}
+
+bool filename_is_valid(const char *p) {
+ const char *e;
+
+ if (isempty(p))
+ return false;
+
+ if (streq(p, "."))
+ return false;
+
+ if (streq(p, ".."))
+ return false;
+
+ e = strchrnul(p, '/');
+ if (*e != 0)
+ return false;
+
+ if (e - p > FILENAME_MAX)
+ return false;
+
+ return true;
+}
+
+bool path_is_safe(const char *p) {
+
+ if (isempty(p))
+ return false;
+
+ if (streq(p, "..") || startswith(p, "../") || endswith(p, "/..") || strstr(p, "/../"))
+ return false;
+
+ if (strlen(p)+1 > PATH_MAX)
+ return false;
+
+ /* The following two checks are not really dangerous, but hey, they still are confusing */
+ if (streq(p, ".") || startswith(p, "./") || endswith(p, "/.") || strstr(p, "/./"))
+ return false;
+
+ if (strstr(p, "//"))
+ return false;
+
+ return true;
+}
+
+char *file_in_same_dir(const char *path, const char *filename) {
+ char *e, *ret;
+ size_t k;
+
+ assert(path);
+ assert(filename);
+
+ /* This removes the last component of path and appends
+ * filename, unless the latter is absolute anyway or the
+ * former isn't */
+
+ if (path_is_absolute(filename))
+ return strdup(filename);
+
+ e = strrchr(path, '/');
+ if (!e)
+ return strdup(filename);
+
+ k = strlen(filename);
+ ret = new(char, (e + 1 - path) + k + 1);
+ if (!ret)
+ return NULL;
+
+ memcpy(mempcpy(ret, path, e + 1 - path), filename, k + 1);
+ return ret;
+}
+
+bool hidden_file_allow_backup(const char *filename) {
+ assert(filename);
+
+ return
+ filename[0] == '.' ||
+ streq(filename, "lost+found") ||
+ streq(filename, "aquota.user") ||
+ streq(filename, "aquota.group") ||
+ endswith(filename, ".rpmnew") ||
+ endswith(filename, ".rpmsave") ||
+ endswith(filename, ".rpmorig") ||
+ endswith(filename, ".dpkg-old") ||
+ endswith(filename, ".dpkg-new") ||
+ endswith(filename, ".dpkg-tmp") ||
+ endswith(filename, ".dpkg-dist") ||
+ endswith(filename, ".dpkg-bak") ||
+ endswith(filename, ".dpkg-backup") ||
+ endswith(filename, ".dpkg-remove") ||
+ endswith(filename, ".ucf-new") ||
+ endswith(filename, ".ucf-old") ||
+ endswith(filename, ".ucf-dist") ||
+ endswith(filename, ".swp");
+}
+
+bool hidden_file(const char *filename) {
+ assert(filename);
+
+ if (endswith(filename, "~"))
+ return true;
+
+ return hidden_file_allow_backup(filename);
+}
+
+#if 0 /// UNNEEDED by elogind
+bool is_device_path(const char *path) {
+
+ /* Returns true on paths that refer to a device, either in
+ * sysfs or in /dev */
+
+ return
+ path_startswith(path, "/dev/") ||
+ path_startswith(path, "/sys/");
+}
#endif // 0