From: Paul Eggert <eggert@cs.ucla.edu>
To: Eli Zaretskii <eliz@gnu.org>
Cc: 13807@debbugs.gnu.org
Subject: bug#13807: updated version to avoid MS-Windows vs non-MS-Windows clashes
Date: Sat, 02 Mar 2013 14:37:29 -0800 [thread overview]
Message-ID: <51327F29.5000600@cs.ucla.edu> (raw)
In-Reply-To: <83vc99tsbm.fsf@gnu.org>
[-- Attachment #1: Type: text/plain, Size: 1220 bytes --]
On 03/02/2013 01:17 PM, Eli Zaretskii wrote:
> Can you describe your testing
> in more details, and what versions of NFS and Windows did you use?
Sure, I created a MS-Windows style lock file .#FILE by hand, then
edited FILE with a GNU/Linux Emacs. I didn't build the MS-Windows
Emacs, and didn't need to use NFS to reproduce the problem.
There's another issue: a GNU/Linux Emacs might be using an
MS-Windows file system that does not support symbolic links. Such
an Emacs should use a regular-file lock, just as MS-Windows Emacs does,
which means that the code to create regular-file locks should be implementable
in POSIXish primitives. Also, locking should work even if the Emacs
instance that created a lock uses a symlink whereas the Emacs instance
trying to get the lock would use a regular file, or vice versa.
It'll take some thinking to get all this to work well. I've written
a first cut for this and have attached it. I have not tested this
on MS-Windows at all, and haven't tested it as much as I'd like on
GNU/Linux, but it should give a feel for the sort of changes that
need to be made. Unfortunately the patch is a bit complicated,
but to some extent this is inherent in such a complicated area.
[-- Attachment #2: filelock2.txt --]
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=== modified file 'etc/ChangeLog'
--- etc/ChangeLog 2013-03-02 20:41:53 +0000
+++ etc/ChangeLog 2013-03-02 22:29:23 +0000
@@ -1,5 +1,8 @@
2013-03-02 Paul Eggert <eggert@cs.ucla.edu>
+ The lock for FILE is now .#FILE and may be a regular file (Bug#13807).
+ * NEWS: Document this.
+
* NEWS: The lock for FILE is now .#FILE or .#-FILE (Bug#13807).
2013-03-01 Michael Albinus <michael.albinus@gmx.de>
=== modified file 'etc/NEWS'
--- etc/NEWS 2013-03-02 20:41:53 +0000
+++ etc/NEWS 2013-03-02 22:29:23 +0000
@@ -320,7 +320,7 @@
** The `defalias-fset-function' property lets you catch calls to defalias
and redirect them to your own function instead of `fset'.
-** The lock for 'DIR/FILE' is now 'DIR/.#FILE' or 'DIR/.#-FILE'.
+** The lock for 'DIR/FILE' is now 'DIR/.#FILE' and may be a regular file.
When you edit DIR/FILE, Emacs normally creates a symbolic link
DIR/.#FILE as a lock that warns other instances of Emacs that DIR/FILE
is being edited. Formerly, if there was already a non-symlink file
@@ -328,9 +328,8 @@
through DIR/.#FILE.9. These fallbacks have been removed, so that
Emacs now no longer locks DIR/FILE in that case.
-On MS-Windows the lock is a regular file DIR/.#-FILE, not a symlink.
-MS-Windows and non-MS-Windows implementations of Emacs ignore each
-other's locks.
+On file systems that do not support symbolic links, the lock is now a
+regular file with contents being what would have been in the symlink.
** The 9th element returned by `file-attributes' is now unspecified.
Formerly, it was t if the file's gid would change if file were deleted
=== modified file 'src/ChangeLog'
--- src/ChangeLog 2013-03-02 21:05:52 +0000
+++ src/ChangeLog 2013-03-02 22:29:23 +0000
@@ -1,5 +1,43 @@
2013-03-02 Paul Eggert <eggert@cs.ucla.edu>
+ FILE's lock is now always .#FILE and may be a regular file (Bug#13807).
+ * filelock.c: Include <c-ctype.h>.
+ (MAX_LFINFO): New top-level constant.
+ (lock_info_type): Remove host member. Add members at, dot.
+ Change user member to be the entire buffer, not a pointer.
+ (FREE_LOCK_INFO): Remove, as the pieces no longer need freeing.
+ (defined_WINDOWSNT): Remove.
+ (MAKE_LOCK_NAME, file_in_lock_file_name):
+ Always use .#FILE (not .#-FILE) for the file lock,
+ even if it is a regular file.
+ (create_lock_file, read_lock_data):
+ Prefer a symbolic link for the lock file, falling back on a
+ regular file if symlinks don't work. Do not try to create
+ symlinks on MS-Windows, due to security hassles. Stick with
+ POSIXish functions (open, read, write, close, readlink, symlink,
+ link, rename, unlink, mkstemp) when creating locks, as a GNUish
+ host may be using a Windowsish file system, and cannot use
+ MS-Windows-only system calls. Fall back on mktemp if mkstemp
+ doesn't work. Don't fail merely because of a symlink-contents
+ length limit in the current file system; fall back on regular
+ files. Increase the symlink contents length limit to 8 KiB, this
+ should be big enough for any real use and doesn't crunch the
+ stack.
+ (create_lock_file, lock_file_1, read_lock_data):
+ Simplify allocation of lock file buffers now that they fit in 8 KiB.
+ (lock_file_1): Return error number, not bool. All callers changed.
+ (read_lock_data): Return size of lock file contents, not Lisp object.
+ All callers changed. Check the contents of a regular-file lock
+ for null bytes. Handle a race condition if some other process
+ replaces a regular-file lock with a symlink lock or vice versa,
+ while we're trying to read the lock.
+ (current_lock_owner): Parse contents more carefully, to help avoid
+ confusing a regular-file lock with some other application's use
+ of the file. Check for lock file contents being too long, or
+ not parsing correctly.
+ (current_lock_owner, lock_if_free, lock_file): Simplify allocation
+ of lock file contents.
+
The lock for FILE is now .#FILE or .#-FILE (Bug#13807).
The old approach, which fell back on DIR/.#FILE.0 through
DIR/.#FILE.9, had race conditions that could not be easily fixed.
=== modified file 'src/filelock.c'
--- src/filelock.c 2013-03-02 21:05:52 +0000
+++ src/filelock.c 2013-03-02 22:29:23 +0000
@@ -38,6 +38,8 @@
#include <errno.h>
+#include <c-ctype.h>
+
#include "lisp.h"
#include "character.h"
#include "buffer.h"
@@ -64,7 +66,7 @@
#define WTMP_FILE "/var/log/wtmp"
#endif
-/* On non-MS-Windows systems, use a symbolic link to represent a lock.
+/* Normally use a symbolic link to represent a lock.
The strategy: to lock a file FN, create a symlink .#FN in FN's
directory, with link data `user@host.pid'. This avoids a single
mount (== failure) point for lock files.
@@ -100,10 +102,11 @@
--karl@cs.umb.edu/karl@hq.ileaf.com.
- On MS-Windows, symbolic links do not work well, so instead of a
- symlink .#FN -> 'user@host.pid', the lock is a regular file .#-FN
- with contents 'user@host.pid'. MS-Windows and non-MS-Windows
- versions of Emacs ignore each other's locks. */
+ On some file systems, notably those of MS-Windows, symbolic links
+ do not work well, so instead of a symlink .#FN -> 'user@host.pid',
+ the lock is a regular file .#FN with contents 'user@host.pid'. The
+ lock is created atomically by creating a nonce file and hard-linking
+ the nonce to .#FN; the link operation establishes the lock. .*/
\f
/* Return the time of the last system boot. */
@@ -284,30 +287,33 @@
}
#endif /* BOOT_TIME */
\f
+/* An arbitrary limit on lock contents length. 8 K should be plenty
+ big enough in practice. */
+enum { MAX_LFINFO = 8 * 1024 };
+
/* Here is the structure that stores information about a lock. */
typedef struct
{
- char *user;
- char *host;
+ /* Location of '@' and '.' in USER. */
+ char *at, *dot;
+
pid_t pid;
time_t boot_time;
+
+ /* Lock file contents USER@HOST.PID with an optional :BOOT_TIME
+ appended. This memory is used as a lock file contents buffer, so
+ it needs room for MAX_LFINFO + 1 bytes. A string "@ (pid NNNN)"
+ may be appended to the USER@HOST while generating a diagnostic,
+ so make room for that too. */
+ char user[MAX_LFINFO + INT_STRLEN_BOUND (printmax_t) + sizeof "@ (pid )"];
} lock_info_type;
-/* Free the two dynamically-allocated pieces in PTR. */
-#define FREE_LOCK_INFO(i) do { xfree ((i).user); xfree ((i).host); } while (0)
-
-#ifdef WINDOWSNT
-enum { defined_WINDOWSNT = 1 };
-#else
-enum { defined_WINDOWSNT = 0 };
-#endif
-
/* Write the name of the lock file for FNAME into LOCKNAME. Length
- will be that of FNAME plus two more for the leading ".#",
- plus one for "-" if MS-Windows, plus one for the null. */
+ will be that of FNAME plus two more for the leading ".#", plus one
+ for the null. */
#define MAKE_LOCK_NAME(lockname, fname) \
- (lockname = SAFE_ALLOCA (SBYTES (fname) + 2 + defined_WINDOWSNT + 1), \
+ (lockname = SAFE_ALLOCA (SBYTES (fname) + 2 + 1), \
fill_in_lock_file_name (lockname, fname))
static void
@@ -319,70 +325,98 @@
memcpy (lockfile, SSDATA (fn), dirlen);
lockfile[dirlen] = '.';
lockfile[dirlen + 1] = '#';
- if (defined_WINDOWSNT)
- lockfile[dirlen + 2] = '-';
- strcpy (lockfile + dirlen + 2 + defined_WINDOWSNT, base);
+ strcpy (lockfile + dirlen + 2, base);
}
+/* Create the lock file FILE with contents CONTENTS. Return 0 if
+ successful, an errno value on failure. If FORCE, remove any
+ existing FILE if necessary. */
+
static int
create_lock_file (char *lfname, char *lock_info_str, bool force)
{
- int err;
-
#ifdef WINDOWSNT
- /* Symlinks are supported only by latest versions of Windows, and
+ /* Symlinks are supported only by later versions of Windows, and
creating them is a privileged operation that often triggers UAC
- elevation prompts. Therefore, instead of using symlinks, we
- create a regular file with the lock info written as its
- contents. */
- {
- /* Deny everybody else any kind of access to the file until we are
- done writing it and close the handle. This makes the entire
- open/write/close operation atomic, as far as other WINDOWSNT
- processes are concerned. */
- int fd = _sopen (lfname,
- _O_WRONLY | _O_BINARY | _O_CREAT | _O_EXCL | _O_NOINHERIT,
- _SH_DENYRW, S_IREAD | S_IWRITE);
-
- if (fd < 0 && errno == EEXIST && force)
- fd = _sopen (lfname, _O_WRONLY | _O_BINARY | _O_TRUNC |_O_NOINHERIT,
- _SH_DENYRW, S_IREAD | S_IWRITE);
- if (fd >= 0)
- {
- ssize_t lock_info_len = strlen (lock_info_str);
-
- err = 0;
- if (emacs_write (fd, lock_info_str, lock_info_len) != lock_info_len)
- err = -1;
- if (emacs_close (fd))
- err = -1;
- }
- else
- err = -1;
- }
+ elevation prompts. Avoid the problem by pretending that
+ 'symlink' does not work. */
+ int err = ENOSYS;
#else
- err = symlink (lock_info_str, lfname);
- if (err != 0 && errno == EEXIST && force)
+ int err = symlink (lock_info_str, lfname) == 0 ? 0 : errno;
+#endif
+
+ if (err == EEXIST && force)
{
unlink (lfname);
- err = symlink (lock_info_str, lfname);
- }
+ err = symlink (lock_info_str, lfname) == 0 ? 0 : errno;
+ }
+
+ /* For some reason Linux kernels return EPERM on file systems
+ that do not support symbolic links. Turn this into ENOSYS. */
+ if (err == EPERM)
+ {
+ char *last_slash = strrchr (lfname, '/');
+ char ch = last_slash[1];
+ last_slash[1] = 0;
+ if (faccessat (AT_FDCWD, lfname, W_OK | X_OK, AT_EACCESS) == 0)
+ err = ENOSYS;
+ last_slash[1] = ch;
+ }
+
+ if (err == ENOSYS || err == ENAMETOOLONG)
+ {
+ static char const nonce_base[] = ".#-emacsXXXXXX";
+ char *last_slash = strrchr (lfname, '/');
+ ptrdiff_t lfdirlen = last_slash + 1 - lfname;
+ USE_SAFE_ALLOCA;
+ char *nonce = SAFE_ALLOCA (lfdirlen + sizeof nonce_base);
+ int fd;
+ memcpy (nonce, lfname, lfdirlen);
+ strcpy (nonce + lfdirlen, nonce_base);
+
+#if HAVE_MKSTEMP
+ fd = mkstemp (nonce);
+#else
+ mktemp (nonce);
+ fd = emacs_open (nonce, O_WRONLY | O_CREAT | O_EXCL | O_BINARY,
+ S_IRUSR | S_IWUSR);
#endif
+ if (fd < 0)
+ err = errno;
+ else
+ {
+ ptrdiff_t lock_info_len = strlen (lock_info_str);
+ err = 0;
+ if (emacs_write (fd, lock_info_str, lock_info_len) != lock_info_len
+ || fchmod (fd, S_IRUSR | S_IRGRP | S_IROTH) != 0)
+ err = errno;
+ if (emacs_close (fd) != 0)
+ err = errno;
+
+ /* Rename NONCE to LFNAME, but do not replace any existing
+ LFNAME unless FORCE. It is OK if there are temporarily
+ two hard links to LFNAME. */
+ if (!err && (force ? rename : link) (nonce, lfname) != 0)
+ err = errno;
+ if ((!force || err) && unlink (nonce) != 0
+ && !err && errno != ENOENT)
+ err = errno;
+ }
+
+ SAFE_FREE ();
+ }
+
return err;
}
/* Lock the lock file named LFNAME.
If FORCE, do so even if it is already locked.
- Return true if successful. */
+ Return 0 if successful, an error number on failure. */
-static bool
+static int
lock_file_1 (char *lfname, bool force)
{
- int err;
- int symlink_errno;
- USE_SAFE_ALLOCA;
-
/* Call this first because it can GC. */
printmax_t boot = get_boot_time ();
@@ -390,20 +424,16 @@
char const *user_name = STRINGP (luser_name) ? SSDATA (luser_name) : "";
Lisp_Object lhost_name = Fsystem_name ();
char const *host_name = STRINGP (lhost_name) ? SSDATA (lhost_name) : "";
- ptrdiff_t lock_info_size = (strlen (user_name) + strlen (host_name)
- + 2 * INT_STRLEN_BOUND (printmax_t)
- + sizeof "@.:");
- char *lock_info_str = SAFE_ALLOCA (lock_info_size);
+ char lock_info_str[MAX_LFINFO + 1];
printmax_t pid = getpid ();
- esprintf (lock_info_str, boot ? "%s@%s.%"pMd":%"pMd : "%s@%s.%"pMd,
- user_name, host_name, pid, boot);
- err = create_lock_file (lfname, lock_info_str, force);
+ if (sizeof lock_info_str
+ <= snprintf (lock_info_str, sizeof lock_info_str,
+ boot ? "%s@%s.%"pMd":%"pMd : "%s@%s.%"pMd,
+ user_name, host_name, pid, boot))
+ return ENAMETOOLONG;
- symlink_errno = errno;
- SAFE_FREE ();
- errno = symlink_errno;
- return err == 0;
+ return create_lock_file (lfname, lock_info_str, force);
}
/* Return true if times A and B are no more than one second apart. */
@@ -414,32 +444,46 @@
return (a - b >= -1 && a - b <= 1);
}
\f
-static Lisp_Object
-read_lock_data (char *lfname)
+/* Read the data for the lock file LFNAME into LFINFO. Read at most
+ MAX_LFINFO + 1 bytes. Return the number of bytes read, or -1
+ (setting errno) on error. */
+
+static ptrdiff_t
+read_lock_data (char *lfname, char lfinfo[MAX_LFINFO + 1])
{
-#ifndef WINDOWSNT
- return emacs_readlinkat (AT_FDCWD, lfname);
-#else
- int fd = emacs_open (lfname, O_RDONLY | O_BINARY, S_IREAD);
- ssize_t nbytes;
- /* 256 chars for user, 1024 chars for host, 10 digits for each of 2 int's. */
- enum { MAX_LFINFO = 256 + 1024 + 10 + 10 + 2 };
- char lfinfo[MAX_LFINFO + 1];
-
- if (fd < 0)
- return Qnil;
-
- nbytes = emacs_read (fd, lfinfo, MAX_LFINFO);
- emacs_close (fd);
-
- if (nbytes > 0)
+ ptrdiff_t nbytes;
+
+ while ((nbytes = readlinkat (AT_FDCWD, lfname, lfinfo, MAX_LFINFO + 1)) < 0
+ && errno == EINVAL)
{
- lfinfo[nbytes] = '\0';
- return build_string (lfinfo);
+ int fd = emacs_open (lfname, O_RDONLY | O_BINARY | O_NOFOLLOW, 0);
+ if (0 <= fd)
+ {
+ int read_errno;
+ nbytes = emacs_read (fd, lfinfo, MAX_LFINFO + 1);
+ read_errno = errno;
+
+ if (emacs_close (fd) != 0)
+ return -1;
+ if (0 < nbytes && memchr (lfinfo, 0, nbytes))
+ {
+ errno = EINVAL;
+ return -1;
+ }
+ errno = read_errno;
+ return nbytes;
+ }
+
+ if (errno != ELOOP)
+ return -1;
+
+ /* readlinkat saw a non-symlink, but emacs_open saw a symlink.
+ The former must have been removed and replaced by the latter.
+ Try again. */
+ QUIT;
}
- else
- return Qnil;
-#endif
+
+ return nbytes;
}
/* Return 0 if nobody owns the lock file LFNAME or the lock is obsolete,
@@ -451,83 +495,84 @@
current_lock_owner (lock_info_type *owner, char *lfname)
{
int ret;
- ptrdiff_t len;
lock_info_type local_owner;
+ ptrdiff_t lfinfolen;
+ pid_t pid;
+ time_t boot_time;
intmax_t n;
- char *at, *dot, *colon;
- Lisp_Object lfinfo_object = read_lock_data (lfname);
- char *lfinfo;
- struct gcpro gcpro1;
-
- /* If nonexistent lock file, all is well; otherwise, got strange error. */
- if (NILP (lfinfo_object))
- return errno == ENOENT ? 0 : -1;
- lfinfo = SSDATA (lfinfo_object);
+ char *at, *dot, *colon, *lfinfo_end;
/* Even if the caller doesn't want the owner info, we still have to
read it to determine return value. */
if (!owner)
owner = &local_owner;
+ /* If nonexistent lock file, all is well; otherwise, got strange error. */
+ lfinfolen = read_lock_data (lfname, owner->user);
+ if (lfinfolen < 0)
+ return errno == ENOENT ? 0 : -1;
+ if (MAX_LFINFO < lfinfolen)
+ return -1;
+ owner->user[lfinfolen] = 0;
+
/* Parse USER@HOST.PID:BOOT_TIME. If can't parse, return -1. */
/* The USER is everything before the last @. */
- at = strrchr (lfinfo, '@');
- dot = strrchr (lfinfo, '.');
- if (!at || !dot)
- return -1;
- len = at - lfinfo;
- GCPRO1 (lfinfo_object);
- owner->user = xmalloc (len + 1);
- memcpy (owner->user, lfinfo, len);
- owner->user[len] = 0;
+ at = memrchr (owner->user, '@', lfinfolen);
+ if (!at)
+ return -1;
+ dot = strrchr (at, '.');
+ if (!dot)
+ return -1;
/* The PID is everything from the last `.' to the `:'. */
+ if (! c_isdigit (dot[1]))
+ return -1;
errno = 0;
- n = strtoimax (dot + 1, NULL, 10);
- owner->pid =
- ((0 <= n && n <= TYPE_MAXIMUM (pid_t)
- && (TYPE_MAXIMUM (pid_t) < INTMAX_MAX || errno != ERANGE))
- ? n : 0);
+ n = strtoimax (dot + 1, &colon, 10);
+ if (! (n <= TYPE_MAXIMUM (pid_t)
+ && (TYPE_MAXIMUM (pid_t) < INTMAX_MAX || errno != ERANGE)))
+ return -1;
+ pid = n;
- colon = strchr (dot + 1, ':');
/* After the `:', if there is one, comes the boot time. */
- n = 0;
- if (colon)
+ switch (*colon)
{
+ case 0:
+ n = 0;
+ break;
+
+ case ':':
+ if (! c_isdigit (colon[1]))
+ return -1;
errno = 0;
- n = strtoimax (colon + 1, NULL, 10);
+ n = strtoimax (colon + 1, &lfinfo_end, 10);
+ if (! (lfinfo_end == owner->user + lfinfolen
+ && n <= TYPE_MAXIMUM (time_t)
+ && (TYPE_MAXIMUM (time_t) < INTMAX_MAX || errno != ERANGE)))
+ return -1;
+ break;
+
+ default:
+ return -1;
}
- owner->boot_time =
- ((0 <= n && n <= TYPE_MAXIMUM (time_t)
- && (TYPE_MAXIMUM (time_t) < INTMAX_MAX || errno != ERANGE))
- ? n : 0);
-
- /* The host is everything in between. */
- len = dot - at - 1;
- owner->host = xmalloc (len + 1);
- memcpy (owner->host, at + 1, len);
- owner->host[len] = 0;
-
- /* We're done looking at the link info. */
- UNGCPRO;
+ boot_time = n;
/* On current host? */
- if (STRINGP (Fsystem_name ())
- && strcmp (owner->host, SSDATA (Fsystem_name ())) == 0)
+ if (STRINGP (Vsystem_name)
+ && dot - (at + 1) == SBYTES (Vsystem_name)
+ && memcmp (at + 1, SSDATA (Vsystem_name), SBYTES (Vsystem_name)) == 0)
{
- if (owner->pid == getpid ())
+ if (pid == getpid ())
ret = 2; /* We own it. */
- else if (owner->pid > 0
- && (kill (owner->pid, 0) >= 0 || errno == EPERM)
- && (owner->boot_time == 0
- || within_one_second (owner->boot_time, get_boot_time ())))
+ else if (pid > 0
+ && (kill (pid, 0) >= 0 || errno == EPERM)
+ && (boot_time == 0
+ || within_one_second (boot_time, get_boot_time ())))
ret = 1; /* An existing process on this machine owns it. */
/* The owner process is dead or has a strange pid (<=0), so try to
zap the lockfile. */
- else if (unlink (lfname) < 0)
- ret = -1;
else
- ret = 0;
+ return unlink (lfname);
}
else
{ /* If we wanted to support the check for stale locks on remote machines,
@@ -535,11 +580,10 @@
ret = 1;
}
- /* Avoid garbage. */
- if (owner == &local_owner || ret <= 0)
- {
- FREE_LOCK_INFO (*owner);
- }
+ owner->at = at;
+ owner->dot = dot;
+ owner->pid = pid;
+ owner->boot_time = boot_time;
return ret;
}
@@ -551,29 +595,25 @@
Return -1 if cannot lock for any other reason. */
static int
-lock_if_free (lock_info_type *clasher, register char *lfname)
+lock_if_free (lock_info_type *clasher, char *lfname)
{
- while (! lock_file_1 (lfname, 0))
+ int err;
+ while ((err = lock_file_1 (lfname, 0)) == EEXIST)
{
- int locker;
-
- if (errno != EEXIST)
- return -1;
-
- locker = current_lock_owner (clasher, lfname);
- if (locker == 2)
- {
- FREE_LOCK_INFO (*clasher);
- return 0; /* We ourselves locked it. */
- }
- else if (locker == 1)
- return 1; /* Someone else has it. */
- else if (locker == -1)
- return -1; /* current_lock_owner returned strange error. */
+ switch (current_lock_owner (clasher, lfname))
+ {
+ case 2:
+ return 0; /* We ourselves locked it. */
+ case 1:
+ return 1; /* Someone else has it. */
+ case -1:
+ return -1; /* current_lock_owner returned strange error. */
+ }
/* We deleted a stale lock; try again to lock the file. */
}
- return 0;
+
+ return err ? -1 : 0;
}
/* lock_file locks file FN,
@@ -645,17 +685,12 @@
if (0 < lock_if_free (&lock_info, lfname))
{
/* Someone else has the lock. Consider breaking it. */
- ptrdiff_t locker_size = (strlen (lock_info.user) + strlen (lock_info.host)
- + INT_STRLEN_BOUND (printmax_t)
- + sizeof "@ (pid )");
- char *locker = SAFE_ALLOCA (locker_size);
printmax_t pid = lock_info.pid;
Lisp_Object attack;
- esprintf (locker, "%s@%s (pid %"pMd")",
- lock_info.user, lock_info.host, pid);
- FREE_LOCK_INFO (lock_info);
+ esprintf (lock_info.dot, " (pid %"pMd")", pid);
- attack = call2 (intern ("ask-user-about-lock"), fn, build_string (locker));
+ attack = call2 (intern ("ask-user-about-lock"), fn,
+ build_string (lock_info.user));
/* Take the lock if the user said so. */
if (!NILP (attack))
lock_file_1 (lfname, 1);
@@ -760,10 +795,7 @@
else if (owner == 2)
ret = Qt;
else
- ret = build_string (locker.user);
-
- if (owner > 0)
- FREE_LOCK_INFO (locker);
+ ret = make_string (locker.user, locker.at - locker.user);
SAFE_FREE ();
return ret;
next prev parent reply other threads:[~2013-03-02 22:37 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-02-24 22:48 bug#13807: The lock for 'DIR/FILE' should always be 'DIR/.#FILE' Paul Eggert
2013-02-25 19:57 ` Glenn Morris
2013-02-25 23:40 ` Paul Eggert
2013-02-26 22:19 ` bug#13807: updated version to avoid MS-Windows vs non-MS-Windows clashes Paul Eggert
2013-02-27 18:49 ` Eli Zaretskii
2013-03-02 20:43 ` Paul Eggert
2013-03-02 21:17 ` Eli Zaretskii
2013-03-02 22:37 ` Paul Eggert [this message]
2013-03-03 16:39 ` Eli Zaretskii
2013-03-03 23:56 ` Paul Eggert
2013-03-04 16:50 ` Eli Zaretskii
2013-03-05 2:25 ` Paul Eggert
2013-03-05 18:38 ` Eli Zaretskii
2013-03-05 22:38 ` Paul Eggert
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