#include "wimlib/assert.h"
#include "wimlib/compiler.h"
#include "wimlib/endianness.h"
-#include "wimlib/dentry.h"
#include "wimlib/encoding.h"
#include "wimlib/error.h"
+#include "wimlib/inode.h"
#include "wimlib/lookup_table.h"
#include "wimlib/reparse.h"
#include "wimlib/resource.h"
-#ifdef __WIN32__
-# include "wimlib/win32.h" /* for win32_get_file_and_vol_ids() */
-#endif
-
#ifdef HAVE_ALLOCA_H
# include <alloca.h>
#endif
#include <errno.h>
#include <stdlib.h>
-/* On-disk format of a symbolic link (WIM_IO_REPARSE_TAG_SYMLINK) or junction
- * point (WIM_IO_REPARSE_TAG_MOUNT_POINT) reparse data buffer. */
-struct reparse_buffer_disk {
- le32 rptag;
- le16 rpdatalen;
- le16 rpreserved;
- le16 substitute_name_offset;
- le16 substitute_name_nbytes;
- le16 print_name_offset;
- le16 print_name_nbytes;
- union {
- struct {
- le32 rpflags;
- u8 data[REPARSE_POINT_MAX_SIZE - 20];
- } _packed_attribute symlink;
- struct {
- u8 data[REPARSE_POINT_MAX_SIZE - 16];
- } _packed_attribute junction;
- };
-} _packed_attribute;
-
-static const utf16lechar volume_junction_prefix[11] = {
- cpu_to_le16('\\'),
- cpu_to_le16('\\'),
- cpu_to_le16('?'),
- cpu_to_le16('\\'),
- cpu_to_le16('V'),
- cpu_to_le16('o'),
- cpu_to_le16('l'),
- cpu_to_le16('u'),
- cpu_to_le16('m'),
- cpu_to_le16('e'),
- cpu_to_le16('{'),
-};
-
-/* Parse the "substitute name" (link target) from a symbolic link or junction
- * reparse point.
- *
- * Return value is:
- *
- * Non-negative integer:
- * The name is an absolute symbolic link in one of several formats,
- * and the return value is the number of UTF-16LE characters that need to
- * be advanced to reach a simple "absolute" path starting with a backslash
- * (i.e. skip over \??\ and/or drive letter)
- * Negative integer:
- * SUBST_NAME_IS_VOLUME_JUNCTION:
- * The name is a volume junction.
- * SUBST_NAME_IS_RELATIVE_LINK:
- * The name is a relative symbolic link.
- * SUBST_NAME_IS_UNKNOWN:
- * The name does not appear to be a valid symbolic link, junction,
- * or mount point.
- */
-int
-parse_substitute_name(const utf16lechar *substitute_name,
- u16 substitute_name_nbytes, u32 rptag)
-{
- u16 substitute_name_nchars = substitute_name_nbytes / 2;
-
- if (substitute_name_nchars >= 7 &&
- substitute_name[0] == cpu_to_le16('\\') &&
- substitute_name[1] == cpu_to_le16('?') &&
- substitute_name[2] == cpu_to_le16('?') &&
- substitute_name[3] == cpu_to_le16('\\') &&
- substitute_name[4] != cpu_to_le16('\0') &&
- substitute_name[5] == cpu_to_le16(':') &&
- substitute_name[6] == cpu_to_le16('\\'))
- {
- /* "Full" symlink or junction (\??\x:\ prefixed path) */
- return 6;
- } else if (rptag == WIM_IO_REPARSE_TAG_MOUNT_POINT &&
- substitute_name_nchars >= 12 &&
- memcmp(substitute_name, volume_junction_prefix,
- sizeof(volume_junction_prefix)) == 0 &&
- substitute_name[substitute_name_nchars - 1] == cpu_to_le16('\\'))
- {
- /* Volume junction. Can't really do anything with it. */
- return SUBST_NAME_IS_VOLUME_JUNCTION;
- } else if (rptag == WIM_IO_REPARSE_TAG_SYMLINK &&
- substitute_name_nchars >= 3 &&
- substitute_name[0] != cpu_to_le16('\0') &&
- substitute_name[1] == cpu_to_le16(':') &&
- substitute_name[2] == cpu_to_le16('\\'))
- {
- /* "Absolute" symlink, with drive letter */
- return 2;
- } else if (rptag == WIM_IO_REPARSE_TAG_SYMLINK &&
- substitute_name_nchars >= 1)
- {
- if (substitute_name[0] == cpu_to_le16('\\'))
- /* "Absolute" symlink, without drive letter */
- return 0;
- else
- /* "Relative" symlink, without drive letter */
- return SUBST_NAME_IS_RELATIVE_LINK;
- } else {
- return SUBST_NAME_IS_UNKNOWN;
- }
-}
-
/*
* Read the data from a symbolic link, junction, or mount point reparse point
* buffer into a `struct reparse_data'.
rpdata->rptag == WIM_IO_REPARSE_TAG_MOUNT_POINT);
rpdata->rpdatalen = le16_to_cpu(rpbuf_disk->rpdatalen);
rpdata->rpreserved = le16_to_cpu(rpbuf_disk->rpreserved);
- substitute_name_offset = le16_to_cpu(rpbuf_disk->substitute_name_offset);
- rpdata->substitute_name_nbytes = le16_to_cpu(rpbuf_disk->substitute_name_nbytes);
- print_name_offset = le16_to_cpu(rpbuf_disk->print_name_offset);
- rpdata->print_name_nbytes = le16_to_cpu(rpbuf_disk->print_name_nbytes);
+ substitute_name_offset = le16_to_cpu(rpbuf_disk->symlink.substitute_name_offset);
+ rpdata->substitute_name_nbytes = le16_to_cpu(rpbuf_disk->symlink.substitute_name_nbytes);
+ print_name_offset = le16_to_cpu(rpbuf_disk->symlink.print_name_offset);
+ rpdata->print_name_nbytes = le16_to_cpu(rpbuf_disk->symlink.print_name_nbytes);
if ((substitute_name_offset & 1) | (print_name_offset & 1) |
(rpdata->substitute_name_nbytes & 1) | (rpdata->print_name_nbytes & 1))
rpbuf_disk->rptag = cpu_to_le32(rpdata->rptag);
rpbuf_disk->rpreserved = cpu_to_le16(rpdata->rpreserved);
- rpbuf_disk->substitute_name_offset = cpu_to_le16(0);
- rpbuf_disk->substitute_name_nbytes = cpu_to_le16(rpdata->substitute_name_nbytes);
- rpbuf_disk->print_name_offset = cpu_to_le16(rpdata->substitute_name_nbytes + 2);
- rpbuf_disk->print_name_nbytes = cpu_to_le16(rpdata->print_name_nbytes);
+ rpbuf_disk->symlink.substitute_name_offset = cpu_to_le16(0);
+ rpbuf_disk->symlink.substitute_name_nbytes = cpu_to_le16(rpdata->substitute_name_nbytes);
+ rpbuf_disk->symlink.print_name_offset = cpu_to_le16(rpdata->substitute_name_nbytes + 2);
+ rpbuf_disk->symlink.print_name_nbytes = cpu_to_le16(rpdata->print_name_nbytes);
if (rpdata->rptag == WIM_IO_REPARSE_TAG_SYMLINK) {
rpbuf_disk->symlink.rpflags = cpu_to_le32(rpdata->rpflags);
lte = lte_override;
}
- if (wim_resource_size(lte) > REPARSE_POINT_MAX_SIZE - 8) {
+ if (lte->size > REPARSE_POINT_MAX_SIZE - 8) {
ERROR("Reparse data is too long!");
return WIMLIB_ERR_INVALID_REPARSE_DATA;
}
- rpdatalen = wim_resource_size(lte);
+ rpdatalen = lte->size;
/* Read the data from the WIM file */
- ret = read_full_resource_into_buf(lte, rpbuf + 8);
+ ret = read_full_stream_into_buf(lte, rpbuf + 8);
if (ret)
return ret;
}
/* UNIX version of getting and setting the data in reparse points */
-#if !defined(__WIN32__)
+#ifndef __WIN32__
+
+static const utf16lechar volume_junction_prefix[11] = {
+ cpu_to_le16('\\'),
+ cpu_to_le16('?'),
+ cpu_to_le16('?'),
+ cpu_to_le16('\\'),
+ cpu_to_le16('V'),
+ cpu_to_le16('o'),
+ cpu_to_le16('l'),
+ cpu_to_le16('u'),
+ cpu_to_le16('m'),
+ cpu_to_le16('e'),
+ cpu_to_le16('{'),
+};
-/* Get the UNIX symlink target from a WIM inode. The inode may be either a
- * "real" symlink (reparse tag WIM_IO_REPARSE_TAG_SYMLINK), or it may be a
- * junction point (reparse tag WIM_IO_REPARSE_TAG_MOUNT_POINT).
+enum {
+ SUBST_NAME_IS_RELATIVE_LINK = -1,
+ SUBST_NAME_IS_VOLUME_JUNCTION = -2,
+ SUBST_NAME_IS_UNKNOWN = -3,
+};
+
+/* Parse the "substitute name" (link target) from a symbolic link or junction
+ * reparse point.
+ *
+ * Return value is:
+ *
+ * Non-negative integer:
+ * The name is an absolute symbolic link in one of several formats,
+ * and the return value is the number of UTF-16LE characters that need to
+ * be advanced to reach a simple "absolute" path starting with a backslash
+ * (i.e. skip over \??\ and/or drive letter)
+ * Negative integer:
+ * SUBST_NAME_IS_VOLUME_JUNCTION:
+ * The name is a volume junction.
+ * SUBST_NAME_IS_RELATIVE_LINK:
+ * The name is a relative symbolic link.
+ * SUBST_NAME_IS_UNKNOWN:
+ * The name does not appear to be a valid symbolic link, junction,
+ * or mount point.
+ */
+static int
+parse_substitute_name(const utf16lechar *substitute_name,
+ u16 substitute_name_nbytes, u32 rptag)
+{
+ u16 substitute_name_nchars = substitute_name_nbytes / 2;
+
+ if (substitute_name_nchars >= 7 &&
+ substitute_name[0] == cpu_to_le16('\\') &&
+ substitute_name[1] == cpu_to_le16('?') &&
+ substitute_name[2] == cpu_to_le16('?') &&
+ substitute_name[3] == cpu_to_le16('\\') &&
+ substitute_name[4] != cpu_to_le16('\0') &&
+ substitute_name[5] == cpu_to_le16(':') &&
+ substitute_name[6] == cpu_to_le16('\\'))
+ {
+ /* "Full" symlink or junction (\??\x:\ prefixed path) */
+ return 6;
+ } else if (rptag == WIM_IO_REPARSE_TAG_MOUNT_POINT &&
+ substitute_name_nchars >= 12 &&
+ memcmp(substitute_name, volume_junction_prefix,
+ sizeof(volume_junction_prefix)) == 0 &&
+ substitute_name[substitute_name_nchars - 1] == cpu_to_le16('\\'))
+ {
+ /* Volume junction. Can't really do anything with it. */
+ return SUBST_NAME_IS_VOLUME_JUNCTION;
+ } else if (rptag == WIM_IO_REPARSE_TAG_SYMLINK &&
+ substitute_name_nchars >= 3 &&
+ substitute_name[0] != cpu_to_le16('\0') &&
+ substitute_name[1] == cpu_to_le16(':') &&
+ substitute_name[2] == cpu_to_le16('\\'))
+ {
+ /* "Absolute" symlink, with drive letter */
+ return 2;
+ } else if (rptag == WIM_IO_REPARSE_TAG_SYMLINK &&
+ substitute_name_nchars >= 1)
+ {
+ if (substitute_name[0] == cpu_to_le16('\\'))
+ /* "Absolute" symlink, without drive letter */
+ return 0;
+ else
+ /* "Relative" symlink, without drive letter */
+ return SUBST_NAME_IS_RELATIVE_LINK;
+ } else {
+ return SUBST_NAME_IS_UNKNOWN;
+ }
+}
+
+/*
+ * Get the UNIX-style symlink target from the WIM inode for a reparse point.
+ * Specifically, this translates the target from UTF-16 to the current multibyte
+ * encoding, strips the drive prefix if present, and replaces backslashes with
+ * forward slashes.
+ *
+ * @inode
+ * The inode to read the symlink from. It must be a reparse point with
+ * tag WIM_IO_REPARSE_TAG_SYMLINK (a real symlink) or
+ * WIM_IO_REPARSE_TAG_MOUNT_POINT (a mount point or junction point).
+ *
+ * @buf
+ * Buffer into which to place the link target.
+ *
+ * @bufsize
+ * Available space in @buf, in bytes.
*
- * This has similar semantics to the UNIX readlink() function, except the path
- * argument is swapped out with the `struct wim_inode' for a reparse point, and
- * on failure a negated error code is returned rather than -1 with errno set. */
+ * @lte_override
+ * If not NULL, the stream from which to read the reparse data. Otherwise,
+ * the reparse data will be read from the unnamed stream of @inode.
+ *
+ * If the entire symbolic link target was placed in the buffer, returns the
+ * number of bytes written. The resulting string is not null-terminated. If
+ * the symbolic link target was too large to be placed in the buffer, the first
+ * @bufsize bytes of it are placed in the buffer and
+ * -ENAMETOOLONG is returned. Otherwise, a negative errno value indicating
+ * another error is returned.
+ */
ssize_t
wim_inode_readlink(const struct wim_inode * restrict inode,
char * restrict buf, size_t bufsize,
return -EIO;
if (parse_reparse_data((const u8*)&rpbuf_disk, rpbuflen, &rpdata))
- return -EIO;
+ return -EINVAL;
ret = utf16le_to_tstr(rpdata.substitute_name,
rpdata.substitute_name_nbytes,
return ret;
}
-#include <sys/stat.h>
-
-static int
-unix_get_ino_and_dev(const char *path, u64 *ino_ret, u64 *dev_ret)
-{
- struct stat stbuf;
- if (stat(path, &stbuf)) {
- if (errno != ENOENT)
- WARNING_WITH_ERRNO("Failed to stat \"%s\"", path);
- /* Treat as a link pointing outside the capture root (it
- * most likely is). */
- return WIMLIB_ERR_STAT;
- } else {
- *ino_ret = stbuf.st_ino;
- *dev_ret = stbuf.st_dev;
- return 0;
- }
-}
-
-#endif /* !defined(__WIN32__) */
-
-/* is_rp_path_separator() - characters treated as path separators in absolute
- * symbolic link targets */
-
-#ifdef __WIN32__
-# define is_rp_path_separator(c) ((c) == L'\\' || (c) == L'/')
-# define os_get_ino_and_dev win32_get_file_and_vol_ids
-#else
-# define is_rp_path_separator(c) ((c) == '/')
-# define os_get_ino_and_dev unix_get_ino_and_dev
-#endif
-
-/* Fix up absolute symbolic link targets--- mostly shared between UNIX and
- * Windows */
-tchar *
-capture_fixup_absolute_symlink(tchar *dest,
- u64 capture_root_ino, u64 capture_root_dev)
-{
- tchar *p = dest;
-
-#ifdef __WIN32__
- /* Skip drive letter */
- if (!is_rp_path_separator(*dest))
- p += 2;
-#endif
-
- DEBUG("Fixing symlink or junction \"%"TS"\"", dest);
- for (;;) {
- tchar save;
- int ret;
- u64 ino;
- u64 dev;
-
- while (is_rp_path_separator(*p))
- p++;
-
- save = *p;
- *p = T('\0');
- ret = os_get_ino_and_dev(dest, &ino, &dev);
- *p = save;
-
- if (ret) /* stat() failed before we got to the capture root---
- assume the link points outside it. */
- return NULL;
-
- if (ino == capture_root_ino && dev == capture_root_dev) {
- /* Link points inside capture root. Return abbreviated
- * path. */
- if (*p == T('\0'))
- *(p - 1) = OS_PREFERRED_PATH_SEPARATOR;
- while (p - 1 >= dest && is_rp_path_separator(*(p - 1)))
- p--;
- #ifdef __WIN32__
- if (!is_rp_path_separator(dest[0])) {
- *--p = dest[1];
- *--p = dest[0];
- }
- #endif
- wimlib_assert(p >= dest);
- return p;
- }
-
- if (*p == T('\0')) {
- /* Link points outside capture root. */
- return NULL;
- }
-
- do {
- p++;
- } while (!is_rp_path_separator(*p) && *p != T('\0'));
- }
-}
+#endif /* !__WIN32__ */
git://wimlib.net / wimlib / blobdiff