diff options
Diffstat (limited to 'grub-core/osdep/unix/relpath.c')
| -rw-r--r-- | grub-core/osdep/unix/relpath.c | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/grub-core/osdep/unix/relpath.c b/grub-core/osdep/unix/relpath.c new file mode 100644 index 0000000..f719950 --- /dev/null +++ b/grub-core/osdep/unix/relpath.c @@ -0,0 +1,151 @@ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 1999,2000,2001,2002,2003,2006,2007,2008,2009,2010,2011,2012,2013 Free Software Foundation, Inc. + * + * GRUB is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * GRUB 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GRUB. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <config-util.h> +#include <config.h> + +#include <sys/types.h> +#include <sys/stat.h> +#include <unistd.h> +#include <stdint.h> +#include <string.h> +#include <errno.h> + +#include <grub/util/misc.h> +#include <grub/emu/hostdisk.h> +#include <grub/emu/getroot.h> +#include <grub/mm.h> + +/* This function never prints trailing slashes (so that its output + can be appended a slash unconditionally). */ +char * +grub_make_system_path_relative_to_its_root (const char *path) +{ + struct stat st; + char *p, *buf, *buf2, *buf3, *ret; + uintptr_t offset = 0; + dev_t num; + size_t len; + char *poolfs = NULL; + + /* canonicalize. */ + p = grub_canonicalize_file_name (path); + if (p == NULL) + grub_util_error (_("failed to get canonical path of `%s'"), path); + +#ifdef __linux__ + ret = grub_make_system_path_relative_to_its_root_os (p); + if (ret) + { + free (p); + return ret; + } +#endif + + /* For ZFS sub-pool filesystems. */ +#ifndef __HAIKU__ + { + char *dummy; + grub_find_zpool_from_dir (p, &dummy, &poolfs); + } +#endif + + len = strlen (p) + 1; + buf = xstrdup (p); + free (p); + + if (stat (buf, &st) < 0) + grub_util_error (_("cannot stat `%s': %s"), buf, strerror (errno)); + + buf2 = xstrdup (buf); + num = st.st_dev; + + /* This loop sets offset to the number of chars of the root + directory we're inspecting. */ + while (1) + { + p = strrchr (buf, '/'); + if (p == NULL) + /* This should never happen. */ + grub_util_error ("%s", + /* TRANSLATORS: canonical pathname is the + complete one e.g. /etc/fstab. It has + to contain `/' normally, if it doesn't + we're in trouble and throw this error. */ + _("no `/' in canonical filename")); + if (p != buf) + *p = 0; + else + *++p = 0; + + if (stat (buf, &st) < 0) + grub_util_error (_("cannot stat `%s': %s"), buf, strerror (errno)); + + /* buf is another filesystem; we found it. */ + if (st.st_dev != num) + { + /* offset == 0 means path given is the mount point. + This works around special-casing of "/" in Un*x. This function never + prints trailing slashes (so that its output can be appended a slash + unconditionally). Each slash in is considered a preceding slash, and + therefore the root directory is an empty string. */ + if (offset == 0) + { + free (buf); + free (buf2); + if (poolfs) + return xasprintf ("/%s/@", poolfs); + return xstrdup (""); + } + else + break; + } + + offset = p - buf; + /* offset == 1 means root directory. */ + if (offset == 1) + { + /* Include leading slash. */ + offset = 0; + break; + } + } + free (buf); + buf3 = xstrdup (buf2 + offset); + buf2[offset] = 0; + + free (buf2); + + /* Remove trailing slashes, return empty string if root directory. */ + len = strlen (buf3); + while (len > 0 && buf3[len - 1] == '/') + { + buf3[len - 1] = '\0'; + len--; + } + + if (poolfs) + { + ret = xasprintf ("/%s/@%s", poolfs, buf3); + free (buf3); + } + else + ret = buf3; + + return ret; +} |