diff options
Diffstat (limited to 'source3/locking/locking.c')
| -rw-r--r-- | source3/locking/locking.c | 131 |
1 files changed, 113 insertions, 18 deletions
diff --git a/source3/locking/locking.c b/source3/locking/locking.c index d72d3908ce..decc36fc03 100644 --- a/source3/locking/locking.c +++ b/source3/locking/locking.c @@ -85,6 +85,37 @@ static const char *lock_type_name(enum brl_type lock_type) } /**************************************************************************** + Utility function to map a lock type correctly depending on the open + mode of a file. +****************************************************************************/ + +static int map_posix_lock_type( files_struct *fsp, enum brl_type lock_type) +{ + if((lock_type == WRITE_LOCK) && !fsp->can_write) { + /* + * Many UNIX's cannot get a write lock on a file opened read-only. + * Win32 locking semantics allow this. + * Do the best we can and attempt a read-only lock. + */ + DEBUG(10,("map_posix_lock_type: Downgrading write lock to read due to read-only file.\n")); + return F_RDLCK; + } else if((lock_type == READ_LOCK) && !fsp->can_read) { + /* + * Ditto for read locks on write only files. + */ + DEBUG(10,("map_posix_lock_type: Changing read lock to write due to write-only file.\n")); + return F_WRLCK; + } + + /* + * This return should be the most normal, as we attempt + * to always open files read/write. + */ + + return (lock_type == READ_LOCK) ? F_RDLCK : F_WRLCK; +} + +/**************************************************************************** Check to see if the given unsigned lock range is within the possible POSIX range. Modifies the given args to be in range if possible, just returns False if not. @@ -98,6 +129,10 @@ static BOOL posix_lock_in_range(SMB_OFF_T *offset_out, SMB_OFF_T *count_out, #if defined(LARGE_SMB_OFF_T) && !defined(HAVE_BROKEN_FCNTL64_LOCKS) + SMB_OFF_T mask2 = ((SMB_OFF_T)0x4) << (SMB_OFF_T_BITS-4); + SMB_OFF_T mask = (mask2<<1); + SMB_OFF_T neg_mask = ~mask; + /* * In this case SMB_OFF_T is 64 bits, * and the underlying system can handle 64 bit signed locks. @@ -108,12 +143,20 @@ static BOOL posix_lock_in_range(SMB_OFF_T *offset_out, SMB_OFF_T *count_out, count = (SMB_OFF_T)u_count; /* + * Deal with a very common case of count of all ones. + * (lock entire file). + */ + + if(count == (SMB_OFF_T)-1) + count &= ~mask; + + /* * POSIX lock ranges cannot be negative. * Fail if any combination becomes negative. */ if(offset < 0 || count < 0 || (offset + count < 0)) { - DEBUG(10,("posix_lock_in_range: negative range offset = %.0f, count = %.0f. Ignoring lock.\n", + DEBUG(10,("posix_lock_in_range: negative range: offset = %.0f, count = %.0f. Ignoring lock.\n", (double)offset, (double)count )); return False; @@ -140,6 +183,14 @@ static BOOL posix_lock_in_range(SMB_OFF_T *offset_out, SMB_OFF_T *count_out, * broken large locking. */ + /* + * Deal with a very common case of count of all ones. + * (lock entire file). + */ + + if(u_count == (SMB_BIG_UINT)-1) + count = 0x7FFFFFFF; + if(((u_offset >> 32) & 0xFFFFFFFF) || ((u_count >> 32) & 0xFFFFFFFF)) { DEBUG(10,("posix_lock_in_range: top 32 bits not zero. offset = %.0f, count = %.0f. Ignoring lock.\n", (double)u_offset, (double)u_count )); @@ -182,6 +233,14 @@ static BOOL posix_lock_in_range(SMB_OFF_T *offset_out, SMB_OFF_T *count_out, * SMB_BIG_UINT is 64 bits, we can do a 32 bit shift. */ + /* + * Deal with a very common case of count of all ones. + * (lock entire file). + */ + + if(u_count == (SMB_BIG_UINT)-1) + count = 0x7FFFFFFF; + if(((u_offset >> 32) & 0xFFFFFFFF) || ((u_count >> 32) & 0xFFFFFFFF)) { DEBUG(10,("posix_lock_in_range: top 32 bits not zero. u_offset = %.0f, u_count = %.0f. Ignoring lock.\n", (double)u_offset, (double)u_count )); @@ -209,6 +268,14 @@ static BOOL posix_lock_in_range(SMB_OFF_T *offset_out, SMB_OFF_T *count_out, * just cast. */ + /* + * Deal with a very common case of count of all ones. + * (lock entire file). + */ + + if(u_count == (SMB_BIG_UINT)-1) + count = 0x7FFFFFFF; + /* Cast from 32 bits unsigned to 32 bits signed. */ offset = (SMB_OFF_T)u_offset; count = (SMB_OFF_T)u_count; @@ -242,22 +309,32 @@ static BOOL posix_lock_in_range(SMB_OFF_T *offset_out, SMB_OFF_T *count_out, /**************************************************************************** POSIX function to see if a file region is locked. Returns True if the - lock could be granted, False if not. + region is locked, False otherwise. ****************************************************************************/ -static BOOL posix_locktest(files_struct *fsp, SMB_BIG_UINT u_offset, SMB_BIG_UINT u_count, enum brl_type lock_type) +static BOOL is_posix_locked(files_struct *fsp, SMB_BIG_UINT u_offset, SMB_BIG_UINT u_count, enum brl_type lock_type) { SMB_OFF_T offset; SMB_OFF_T count; - DEBUG(10,("posix_locktest: File %s, offset = %.0f, count = %.0f, type = %s\n", + DEBUG(10,("is_posix_locked: File %s, offset = %.0f, count = %.0f, type = %s\n", fsp->fsp_name, (double)offset, (double)count, lock_type_name(lock_type) )); + /* + * If the requested lock won't fit in the POSIX range, we will + * never set it, so presume it is not locked. + */ + if(!posix_lock_in_range(&offset, &count, u_offset, u_count)) - return True; + return False; - /* Placeholder - for now always return that the lock could be granted. */ - return True; + /* + * Note that most UNIX's can *test* for a write lock on + * a read-only fd, just not *set* a write lock on a read-only + * fd. So we don't need to use map_lock_type here. + */ + + return fcntl_lock(fsp->fd,SMB_F_GETLK,offset,count,lock_type); } /**************************************************************************** @@ -265,40 +342,58 @@ static BOOL posix_locktest(files_struct *fsp, SMB_BIG_UINT u_offset, SMB_BIG_UIN lock could be granted, False if not. ****************************************************************************/ -static BOOL get_posix_lock(files_struct *fsp, SMB_BIG_UINT u_offset, SMB_BIG_UINT u_count, enum brl_type lock_type) +static BOOL set_posix_lock(files_struct *fsp, SMB_BIG_UINT u_offset, SMB_BIG_UINT u_count, enum brl_type lock_type) { SMB_OFF_T offset; SMB_OFF_T count; + BOOL ret = True; - DEBUG(5,("get_posix_lock: File %s, offset = %.0f, count = %.0f, type = %s\n", + DEBUG(5,("set_posix_lock: File %s, offset = %.0f, count = %.0f, type = %s\n", fsp->fsp_name, (double)offset, (double)count, lock_type_name(lock_type) )); + /* + * If the requested lock won't fit in the POSIX range, we will + * pretend it was successful. + */ + if(!posix_lock_in_range(&offset, &count, u_offset, u_count)) return True; - /* Placeholder - for now always return that the lock could be granted. */ - fsp->num_posix_locks++; - return True; + ret = fcntl_lock(fsp->fd,SMB_F_SETLK,offset,count,map_posix_lock_type(fsp,lock_type)); + + if(ret) + fsp->num_posix_locks++; + + return ret; } /**************************************************************************** POSIX function to release a lock. Returns True if the - lock could be granted, False if not. + lock could be released, False if not. ****************************************************************************/ static BOOL release_posix_lock(files_struct *fsp, SMB_BIG_UINT u_offset, SMB_BIG_UINT u_count) { SMB_OFF_T offset; SMB_OFF_T count; + BOOL ret; DEBUG(5,("release_posix_lock: File %s, offset = %.0f, count = %.0f\n", fsp->fsp_name, (double)offset, (double)count )); + /* + * If the requested lock won't fit in the POSIX range, we will + * pretend it was successful. + */ + if(!posix_lock_in_range(&offset, &count, u_offset, u_count)) return True; - /* Placeholder - for now always return that the lock could be granted. */ - fsp->num_posix_locks--; + ret = fcntl_lock(fsp->fd,SMB_F_SETLK,offset,count,F_UNLCK); + + if(ret) + fsp->num_posix_locks--; + return True; } @@ -332,7 +427,7 @@ BOOL is_locked(files_struct *fsp,connection_struct *conn, */ if(!ret && !EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type) && lp_posix_locking(snum)) - ret = !posix_locktest(fsp, offset, count, lock_type); + ret = is_posix_locked(fsp, offset, count, lock_type); return ret; } @@ -371,7 +466,7 @@ BOOL do_lock(files_struct *fsp,connection_struct *conn, * Try and get a POSIX lock on this range. */ - ok = get_posix_lock(fsp, offset, count, lock_type); + ok = set_posix_lock(fsp, offset, count, lock_type); if(!ok) { /* @@ -393,10 +488,10 @@ BOOL do_lock(files_struct *fsp,connection_struct *conn, return True; /* Got lock */ } - /**************************************************************************** Utility function called by unlocking requests. ****************************************************************************/ + BOOL do_unlock(files_struct *fsp,connection_struct *conn, SMB_BIG_UINT count,SMB_BIG_UINT offset, int *eclass,uint32 *ecode) |