mirrors/tar
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Treat fishy-looking hard links like fishy-looking symlinks.

Browse Source 
(struct delayed_set_stat): Rename after_symlinks
member to after_links.  All uses changed.
(struct delayed_link): Renamed from struct delayed_symlink.
All uses changed.  New member is_symlink.
(delayed_link_head): Renamed from delayed_symlink_head.  All uses
changed.
(create_placeholder_file): New function, taken from extract_symlink.
(extract_link): Create placeholders for fishy-looking hard links.
(extract_symlink): Move code into create_placeholder_file.
(apply_delayed_links): Renamed from apply_delayed_symlinks.
All uses changed.  Create both hard links and symlinks.
This commit is contained in:
Paul Eggert
2005-09-12 18:45:59 +00:00
parent 3070fff7d7
commit af5d05729a
1 changed files with 126 additions and 104 deletions
Download Patch File Download Diff File Expand all files Collapse all files

230
src/extract.c
View File

@@ -48,8 +48,8 @@ enum permstatus
/* List of directories whose statuses we need to extract after we've
finished extracting their subsidiary files. If you consider each
contiguous subsequence of elements of the form [D]?[^D]*, where [D]
represents an element where AFTER_SYMLINKS is nonzero and [^D]
represents an element where AFTER_SYMLINKS is zero, then the head
represents an element where AFTER_LINKS is nonzero and [^D]
represents an element where AFTER_LINKS is zero, then the head
of the subsequence has the longest name, and each non-head element
in the prefix is an ancestor (in the directory hierarchy) of the
preceding element. */
@@ -61,28 +61,31 @@ struct delayed_set_stat
size_t file_name_len;
mode_t invert_permissions;
enum permstatus permstatus;
bool after_symlinks;
bool after_links;
char file_name[1];
};
static struct delayed_set_stat *delayed_set_stat_head;
/* List of symbolic links whose creation we have delayed. */
struct delayed_symlink
/* List of links whose creation we have delayed. */
struct delayed_link
{
/* The next delayed symbolic link in the list. */
struct delayed_symlink *next;
/* The next delayed link in the list. */
struct delayed_link *next;
/* The device, inode number and last-modified time of the placeholder. */
dev_t dev;
ino_t ino;
time_t mtime;
/* The desired owner and group of the symbolic link. */
/* True if the link is symbolic. */
bool is_symlink;
/* The desired owner and group of the link, if it is a symlink. */
uid_t uid;
gid_t gid;
/* A list of sources for this symlink. The sources are all to be
/* A list of sources for this link. The sources are all to be
hard-linked together. */
struct string_list *sources;
@@ -90,7 +93,7 @@ struct delayed_symlink
char target[1];
};
static struct delayed_symlink *delayed_symlink_head;
static struct delayed_link *delayed_link_head;
struct string_list
{
@@ -322,7 +325,7 @@ delay_set_stat (char const *file_name, struct stat const *stat_info,
strcpy (data->file_name, file_name);
data->invert_permissions = invert_permissions;
data->permstatus = permstatus;
data->after_symlinks = 0;
data->after_links = 0;
data->stat_info = *stat_info;
data->next = delayed_set_stat_head;
delayed_set_stat_head = data;
@@ -361,7 +364,7 @@ repair_delayed_set_stat (char const *dir,
quotearg_colon (dir)));
}
/* After a file/link/symlink/directory creation has failed, see if
/* After a file/link/directory creation has failed, see if
it's because some required directory was not present, and if so,
create all required directories. Return non-zero if a directory
was created. */
@@ -513,12 +516,12 @@ maybe_recoverable (char *file_name, int *interdir_made)
}
/* Fix the statuses of all directories whose statuses need fixing, and
which are not ancestors of FILE_NAME. If AFTER_SYMLINKS is
which are not ancestors of FILE_NAME. If AFTER_LINKS is
nonzero, do this for all such directories; otherwise, stop at the
first directory that is marked to be fixed up only after delayed
symlinks are applied. */
links are applied. */
static void
apply_nonancestor_delayed_set_stat (char const *file_name, bool after_symlinks)
apply_nonancestor_delayed_set_stat (char const *file_name, bool after_links)
{
size_t file_name_len = strlen (file_name);
bool check_for_renamed_directories = 0;
@@ -530,9 +533,9 @@ apply_nonancestor_delayed_set_stat (char const *file_name, bool after_symlinks)
struct stat st;
struct stat const *cur_info = 0;
check_for_renamed_directories |= data->after_symlinks;
check_for_renamed_directories |= data->after_links;
if (after_symlinks < data->after_symlinks
if (after_links < data->after_links
|| (data->file_name_len < file_name_len
&& file_name[data->file_name_len]
&& (ISSLASH (file_name[data->file_name_len])
@@ -776,6 +779,82 @@ extract_file (char *file_name, int typeflag)
return status;
}
/* Create a placeholder file with name FILE_NAME, which will be
replaced after other extraction is done by a symbolic link if
IS_SYMLINK is true, and by a hard link otherwise. Set
*INTERDIR_MADE if an intermediate directory is made in the
process. */
static int
create_placeholder_file (char *file_name, bool is_symlink, int *interdir_made)
{
int fd;
struct stat st;
while ((fd = open (file_name, O_WRONLY | O_CREAT | O_EXCL, 0)) < 0)
if (! maybe_recoverable (file_name, interdir_made))
break;
if (fd < 0)
open_error (file_name);
else if (fstat (fd, &st) != 0)
{
stat_error (file_name);
close (fd);
}
else if (close (fd) != 0)
close_error (file_name);
else
{
struct delayed_set_stat *h;
struct delayed_link *p =
xmalloc (offsetof (struct delayed_link, target)
+ strlen (current_stat_info.link_name)
+ 1);
p->next = delayed_link_head;
delayed_link_head = p;
p->dev = st.st_dev;
p->ino = st.st_ino;
p->mtime = st.st_mtime;
p->is_symlink = is_symlink;
if (is_symlink)
{
p->uid = current_stat_info.stat.st_uid;
p->gid = current_stat_info.stat.st_gid;
}
p->sources = xmalloc (offsetof (struct string_list, string)
+ strlen (file_name) + 1);
p->sources->next = 0;
strcpy (p->sources->string, file_name);
strcpy (p->target, current_stat_info.link_name);
h = delayed_set_stat_head;
if (h && ! h->after_links
&& strncmp (file_name, h->file_name, h->file_name_len) == 0
&& ISSLASH (file_name[h->file_name_len])
&& (base_name (file_name) == file_name + h->file_name_len + 1))
{
do
{
h->after_links = 1;
if (stat (h->file_name, &st) != 0)
stat_error (h->file_name);
else
{
h->stat_info.st_dev = st.st_dev;
h->stat_info.st_ino = st.st_ino;
}
}
while ((h = h->next) && ! h->after_links);
}
return 0;
}
return -1;
}
static int
extract_link (char *file_name, int typeflag)
{
@@ -783,6 +862,9 @@ extract_link (char *file_name, int typeflag)
true, absolute_names_option);
int interdir_made = 0;
if (! absolute_names_option && contains_dot_dot (link_name))
return create_placeholder_file (file_name, false, &interdir_made);
do
{
struct stat st1, st2;
@@ -792,7 +874,7 @@ extract_link (char *file_name, int typeflag)
if (status == 0)
{
struct delayed_symlink *ds = delayed_symlink_head;
struct delayed_link *ds = delayed_link_head;
if (ds && lstat (link_name, &st1) == 0)
for (; ds; ds = ds->next)
if (ds->dev == st1.st_dev
@@ -831,87 +913,22 @@ static int
extract_symlink (char *file_name, int typeflag)
{
#ifdef HAVE_SYMLINK
int status, fd;
int status;
int interdir_made = 0;
if (absolute_names_option
|| ! (IS_ABSOLUTE_FILE_NAME (current_stat_info.link_name)
|| contains_dot_dot (current_stat_info.link_name)))
{
while ((status = symlink (current_stat_info.link_name, file_name)))
if (!maybe_recoverable (file_name, &interdir_made))
break;
if (! absolute_names_option
&& (IS_ABSOLUTE_FILE_NAME (current_stat_info.link_name)
|| contains_dot_dot (current_stat_info.link_name)))
return create_placeholder_file (file_name, true, &interdir_made);
if (status == 0)
set_stat (file_name, &current_stat_info.stat, 0, 0, 0, SYMTYPE);
else
symlink_error (current_stat_info.link_name, file_name);
}
while ((status = symlink (current_stat_info.link_name, file_name)))
if (!maybe_recoverable (file_name, &interdir_made))
break;
if (status == 0)
set_stat (file_name, &current_stat_info.stat, 0, 0, 0, SYMTYPE);
else
{
/* This symbolic link is potentially dangerous. Don't
create it now; instead, create a placeholder file, which
will be replaced after other extraction is done. */
struct stat st;
while ((fd = open (file_name, O_WRONLY | O_CREAT | O_EXCL, 0)) < 0)
if (! maybe_recoverable (file_name, &interdir_made))
break;
status = -1;
if (fd < 0)
open_error (file_name);
else if (fstat (fd, &st) != 0)
{
stat_error (file_name);
close (fd);
}
else if (close (fd) != 0)
close_error (file_name);
else
{
struct delayed_set_stat *h;
struct delayed_symlink *p = xmalloc (offsetof (struct delayed_symlink, target)
+ strlen (current_stat_info.link_name)
+ 1);
p->next = delayed_symlink_head;
delayed_symlink_head = p;
p->dev = st.st_dev;
p->ino = st.st_ino;
p->mtime = st.st_mtime;
p->uid = current_stat_info.stat.st_uid;
p->gid = current_stat_info.stat.st_gid;
p->sources = xmalloc (offsetof (struct string_list, string)
+ strlen (file_name) + 1);
p->sources->next = 0;
strcpy (p->sources->string, file_name);
strcpy (p->target, current_stat_info.link_name);
h = delayed_set_stat_head;
if (h && ! h->after_symlinks
&& strncmp (file_name, h->file_name, h->file_name_len) == 0
&& ISSLASH (file_name[h->file_name_len])
&& (base_name (file_name) == file_name + h->file_name_len + 1))
{
do
{
h->after_symlinks = 1;
if (stat (h->file_name, &st) != 0)
stat_error (h->file_name);
else
{
h->stat_info.st_dev = st.st_dev;
h->stat_info.st_ino = st.st_ino;
}
}
while ((h = h->next) && ! h->after_symlinks);
}
status = 0;
}
}
symlink_error (current_stat_info.link_name, file_name);
return status;
#else
@@ -1180,11 +1197,11 @@ extract_archive (void)
/* Extract the symbolic links whose final extraction were delayed. */
static void
apply_delayed_symlinks (void)
apply_delayed_links (void)
{
struct delayed_symlink *ds;
struct delayed_link *ds;
for (ds = delayed_symlink_head; ds; )
for (ds = delayed_link_head; ds; )
{
struct string_list *sources = ds->sources;
char const *valid_source = 0;
@@ -1195,7 +1212,7 @@ apply_delayed_symlinks (void)
struct stat st;
/* Make sure the placeholder file is still there. If not,
don't create a symlink, as the placeholder was probably
don't create a link, as the placeholder was probably
removed by a later extraction. */
if (lstat (source, &st) == 0
&& st.st_dev == ds->dev
@@ -1208,6 +1225,11 @@ apply_delayed_symlinks (void)
unlink_error (source);
else if (valid_source && link (valid_source, source) == 0)
;
else if (!ds->is_symlink)
{
if (link (ds->target, source) != 0)
link_error (ds->target, source);
}
else if (symlink (ds->target, source) != 0)
symlink_error (ds->target, source);
else
@@ -1228,13 +1250,13 @@ apply_delayed_symlinks (void)
}
{
struct delayed_symlink *next = ds->next;
struct delayed_link *next = ds->next;
free (ds);
ds = next;
}
}
delayed_symlink_head = 0;
delayed_link_head = 0;
}
/* Finish the extraction of an archive. */
@@ -1244,12 +1266,12 @@ extract_finish (void)
/* First, fix the status of ordinary directories that need fixing. */
apply_nonancestor_delayed_set_stat ("", 0);
/* Then, apply delayed symlinks, so that they don't affect delayed
/* Then, apply delayed links, so that they don't affect delayed
directory status-setting for ordinary directories. */
apply_delayed_symlinks ();
apply_delayed_links ();
/* Finally, fix the status of directories that are ancestors
of delayed symlinks. */
of delayed links. */
apply_nonancestor_delayed_set_stat ("", 1);
}