This has the advantage that we use the same sscanf pattern as in other places where /proc/self/mountinfo is parsed, and we avoid bugreports from people who are confused about missing CONFIG_FHANDLE.
An alternate solution would be to warn when (at runtime) name_to_handle_at is detected to be missing, but this is used in early boot, and seems less useful overall. https://bugzilla.redhat.com/show_bug.cgi?id=1072966 --- Hi Kay, it seems that handles are not crucial, and the simplified version below works too. Is there something I'm missing? Zbyszek README | 2 +- src/libudev/libudev-monitor.c | 49 ++++++++++++++++++++++++------------------- src/shared/path-util.c | 6 +----- 3 files changed, 30 insertions(+), 27 deletions(-) diff --git a/README b/README index cecbcbf..983f02f 100644 --- a/README +++ b/README @@ -51,7 +51,6 @@ REQUIREMENTS: CONFIG_NET CONFIG_SYSFS CONFIG_PROC_FS - CONFIG_FHANDLE (libudev, mount and bind mount handling) Udev will fail to work with the legacy layout: CONFIG_SYSFS_DEPRECATED=n @@ -79,6 +78,7 @@ REQUIREMENTS: CONFIG_TMPFS_POSIX_ACL CONFIG_TMPFS_XATTR CONFIG_SECCOMP + CONFIG_FHANDLE (libudev, mount and bind mount handling) For systemd-bootchart, several proc debug interfaces are required: CONFIG_SCHEDSTATS diff --git a/src/libudev/libudev-monitor.c b/src/libudev/libudev-monitor.c index 3f7436b..0590002 100644 --- a/src/libudev/libudev-monitor.c +++ b/src/libudev/libudev-monitor.c @@ -108,39 +108,46 @@ static struct udev_monitor *udev_monitor_new(struct udev *udev) /* we consider udev running when /dev is on devtmpfs */ static bool udev_has_devtmpfs(struct udev *udev) { - struct file_handle *h; - int mount_id; _cleanup_fclose_ FILE *f = NULL; - char line[LINE_MAX], *e; - int r; - - h = alloca(MAX_HANDLE_SZ); - h->handle_bytes = MAX_HANDLE_SZ; - r = name_to_handle_at(AT_FDCWD, "/dev", h, &mount_id, 0); - if (r < 0) - return false; - + int i; f = fopen("/proc/self/mountinfo", "re"); if (!f) return false; - FOREACH_LINE(line, f, return false) { - int mid; - - if (sscanf(line, "%i", &mid) != 1) - continue; + for (i = 1;; i++) { + _cleanup_free_ char *where = NULL, *fstype = NULL; + int k; + + k = fscanf(f, + "%*s " /* (1) mount id */ + "%*s " /* (2) parent id */ + "%*s " /* (3) major:minor */ + "%*s " /* (4) root */ + "%ms " /* (5) mount point */ + "%*s" /* (6) mount options */ + "%*[^-]" /* (7) optional fields */ + "- " /* (8) separator */ + "%ms " /* (9) file system type */ + "%*s" /* (10) mount source */ + "%*s" /* (11) mount options 2 */ + "%*[^\n]", /* some rubbish at the end */ + &where, + &fstype); + + if (k == EOF) + break; - if (mid != mount_id) + if (k != 2) { + log_warning("Failed to parse /proc/self/mountinfo:%u.", i); continue; + } - e = strstr(line, " - "); - if (!e) + if (!streq(where, "/dev")) continue; /* accept any name that starts with the currently expected type */ - if (startswith(e + 3, "devtmpfs")) - return true; + return streq(fstype, "devtmpfs"); } return false; diff --git a/src/shared/path-util.c b/src/shared/path-util.c index e35d7f8..5beb5f8 100644 --- a/src/shared/path-util.c +++ b/src/shared/path-util.c @@ -324,7 +324,7 @@ bool path_equal(const char *a, const char *b) { } int path_is_mount_point(const char *t, bool allow_symlink) { - char *parent; + _cleanup_free_ char *parent = NULL; int r; struct file_handle *h; int mount_id, mount_id_parent; @@ -360,8 +360,6 @@ int path_is_mount_point(const char *t, bool allow_symlink) { h->handle_bytes = MAX_HANDLE_SZ; r = name_to_handle_at(AT_FDCWD, parent, h, &mount_id_parent, 0); - free(parent); - if (r < 0) { /* The parent can't do name_to_handle_at() but the * directory we are interested in can? If so, it must @@ -392,8 +390,6 @@ fallback: return r; r = lstat(parent, &b); - free(parent); - if (r < 0) return -errno; -- 1.8.5.2 _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
