Make PUT with DAV_MODE_WRITE_TRUNC create a temporary file first and, when the

transfer has been completed successfully, move it over the old file.

Since this would break inode keyed locking, switch to filename keyed locking
exclusively.

PR: 39815
Submitted by: Paul Querna, Stefan Fritsch


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@834049 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 13 insertions, 95 deletions

diff --git a/modules/dav/fs/lock.c b/modules/dav/fs/lock.c
index 32220a79ba..97aa7eab45 100644
--- a/modules/dav/fs/lock.c
+++ b/modules/dav/fs/lock.c
@@ -48,9 +48,7 @@
 **
 ** KEY
 **
-** The database is keyed by a key_type unsigned char (DAV_TYPE_INODE or
-** DAV_TYPE_FNAME) followed by inode and device number if possible,
-** otherwise full path (in the case of Win32 or lock-null resources).
+** The database is keyed by the full path.
 **
 ** VALUE
 **
@@ -82,9 +80,6 @@
 #define DAV_LOCK_DIRECT         1
 #define DAV_LOCK_INDIRECT       2
 
-#define DAV_TYPE_INODE          10
-#define DAV_TYPE_FNAME          11
-
 
 /* ack. forward declare. */
 static dav_error * dav_fs_remove_locknull_member(apr_pool_t *p,
@@ -372,68 +367,26 @@ static void dav_fs_close_lockdb(dav_lockdb *lockdb)
 }
 
 /*
-** dav_fs_build_fname_key
-**
-** Given a pathname, build a DAV_TYPE_FNAME lock database key.
+** dav_fs_build_key:  Given a resource, return a apr_datum_t key
+**    to look up lock information for this file.
 */
-static apr_datum_t dav_fs_build_fname_key(apr_pool_t *p, const char *pathname)
+static apr_datum_t dav_fs_build_key(apr_pool_t *p,
+                                    const dav_resource *resource)
 {
+    const char *pathname = dav_fs_pathname(resource);
     apr_datum_t key;
 
     /* ### does this allocation have a proper lifetime? need to check */
     /* ### can we use a buffer for this? */
 
-    /* size is TYPE + pathname + null */
-    key.dsize = strlen(pathname) + 2;
-    key.dptr = apr_palloc(p, key.dsize);
-    *key.dptr = DAV_TYPE_FNAME;
-    memcpy(key.dptr + 1, pathname, key.dsize - 1);
+    key.dsize = strlen(pathname) + 1;
+    key.dptr = apr_pstrmemdup(p, pathname, key.dsize - 1);
     if (key.dptr[key.dsize - 2] == '/')
         key.dptr[--key.dsize - 1] = '\0';
     return key;
 }
 
 /*
-** dav_fs_build_key:  Given a resource, return a apr_datum_t key
-**    to look up lock information for this file.
-**
-**    (inode/dev not supported or file is lock-null):
-**       apr_datum_t->dvalue = full path
-**
-**    (inode/dev supported and file exists ):
-**       apr_datum_t->dvalue = inode, dev
-*/
-static apr_datum_t dav_fs_build_key(apr_pool_t *p,
-                                    const dav_resource *resource)
-{
-    const char *file = dav_fs_pathname(resource);
-    apr_datum_t key;
-    apr_finfo_t finfo;
-    apr_status_t rv;
-
-    /* ### use lstat() ?? */
-    /*
-     * XXX: What for platforms with no IDENT (dev/inode)?
-     */
-    rv = apr_stat(&finfo, file, APR_FINFO_IDENT, p);
-    if ((rv == APR_SUCCESS || rv == APR_INCOMPLETE)
-        && ((finfo.valid & APR_FINFO_IDENT) == APR_FINFO_IDENT))
-    {
-        /* ### can we use a buffer for this? */
-        key.dsize = 1 + sizeof(finfo.inode) + sizeof(finfo.device);
-        key.dptr = apr_palloc(p, key.dsize);
-        *key.dptr = DAV_TYPE_INODE;
-        memcpy(key.dptr + 1, &finfo.inode, sizeof(finfo.inode));
-        memcpy(key.dptr + 1 + sizeof(finfo.inode), &finfo.device,
-               sizeof(finfo.device));
-
-        return key;
-    }
-
-    return dav_fs_build_fname_key(p, file);
-}
-
-/*
 ** dav_fs_lock_expired:  return 1 (true) if the given timeout is in the past
 **    or present (the lock has expired), or 0 (false) if in the future
 **    (the lock has not yet expired).
@@ -626,15 +579,14 @@ static dav_error * dav_fs_load_lock_record(dav_lockdb *lockdb, apr_datum_t key,
                 need_save = DAV_TRUE;
 
                 /* Remove timed-out locknull fm .locknull list */
-                if (*key.dptr == DAV_TYPE_FNAME) {
-                    const char *fname = key.dptr + 1;
+                {
                     apr_finfo_t finfo;
                     apr_status_t rv;
 
                     /* if we don't see the file, then it's a locknull */
-                    rv = apr_stat(&finfo, fname, APR_FINFO_MIN | APR_FINFO_LINK, p);
+                    rv = apr_stat(&finfo, key.dptr, APR_FINFO_MIN | APR_FINFO_LINK, p);
                     if (rv != APR_SUCCESS && rv != APR_INCOMPLETE) {
-                        if ((err = dav_fs_remove_locknull_member(p, fname, &buf)) != NULL) {
+                        if ((err = dav_fs_remove_locknull_member(p, key.dptr, &buf)) != NULL) {
                             /* ### push a higher-level description? */
                             return err;
                         }
@@ -989,13 +941,8 @@ static dav_error * dav_fs_add_locknull_state(
 
 /*
 ** dav_fs_remove_locknull_state:  Given a request, check to see if r->filename
-**    is/was a lock-null resource.  If so, return it to an existant state.
-**
-**    ### this function is broken... it doesn't check!
-**
-**    In this implementation, this involves two things:
-**    (a) remove it from the list in the appropriate .DAV/locknull file
-**    (b) on *nix, convert the key from a filename to an inode.
+**    is/was a lock-null resource.  If so, return it to an existant state, i.e.
+**    remove it from the list in the appropriate .DAV/locknull file.
 */
 static dav_error * dav_fs_remove_locknull_state(
     dav_lockdb *lockdb,
@@ -1011,35 +958,6 @@ static dav_error * dav_fs_remove_locknull_state(
         return err;
     }
 
-    {
-        dav_lock_discovery *ld;
-        dav_lock_indirect  *id;
-        apr_datum_t key;
-
-        /*
-        ** Fetch the lock(s) that made the resource lock-null. Remove
-        ** them under the filename key. Obtain the new inode key, and
-        ** save the same lock information under it.
-        */
-        key = dav_fs_build_fname_key(p, pathname);
-        if ((err = dav_fs_load_lock_record(lockdb, key, DAV_CREATE_LIST,
-                                           &ld, &id)) != NULL) {
-            /* ### insert a higher-level error description */
-            return err;
-        }
-
-        if ((err = dav_fs_save_lock_record(lockdb, key, NULL, NULL)) != NULL) {
-            /* ### insert a higher-level error description */
-            return err;
-        }
-
-        key = dav_fs_build_key(p, resource);
-        if ((err = dav_fs_save_lock_record(lockdb, key, ld, id)) != NULL) {
-            /* ### insert a higher-level error description */
-            return err;
-        }
-    }
-
     return NULL;
 }