Patch based on work from James Peach <jpeach@sgi.com> to convert over to

using pread/pwrite. Modified a little to ensure fsp->pos is correct.
Fix for #889.
Jeremy.
(This used to be commit 3a24dc868d95c9bcc2ac3a0dbd50e6e226ac0841)

3 files changed, 255 insertions, 131 deletions

diff --git a/source3/smbd/fileio.c b/source3/smbd/fileio.c
index 84339c3a6f..f395954d05 100644
--- a/source3/smbd/fileio.c
+++ b/source3/smbd/fileio.c
@@ -95,16 +95,14 @@ ssize_t read_file(files_struct *fsp,char *data,SMB_OFF_T pos,size_t n)
 
 	flush_write_cache(fsp, READ_FLUSH);
 
-	if (seek_file(fsp,pos) == -1) {
-		DEBUG(3,("read_file: Failed to seek to %.0f\n",(double)pos));
-		return(ret);
-	}
-  
+	fsp->pos = pos;
+
 	if (n > 0) {
 #ifdef DMF_FIX
 		int numretries = 3;
 tryagain:
-		readret = SMB_VFS_READ(fsp,fsp->fd,data,n);
+		readret = SMB_VFS_PREAD(fsp,fsp->fd,data,n,pos);
+
 		if (readret == -1) {
 			if ((errno == EAGAIN) && numretries) {
 				DEBUG(3,("read_file EAGAIN retry in 10 seconds\n"));
@@ -115,7 +113,8 @@ tryagain:
 			return -1;
 		}
 #else /* NO DMF fix. */
-		readret = SMB_VFS_READ(fsp,fsp->fd,data,n);
+		readret = SMB_VFS_PREAD(fsp,fsp->fd,data,n,pos);
+
 		if (readret == -1)
 			return -1;
 #endif
@@ -143,10 +142,12 @@ static ssize_t real_write_file(files_struct *fsp,char *data,SMB_OFF_T pos, size_
 {
 	ssize_t ret;
 
-	if ((pos != -1) && (seek_file(fsp,pos) == -1))
-		return -1;
-
-	ret = vfs_write_data(fsp,data,n);
+        if (pos == -1)
+                ret = vfs_write_data(fsp, data, n);
+        else {
+		fsp->pos = pos;
+                ret = vfs_pwrite_data(fsp, data, n, pos);
+	}
 
 	DEBUG(10,("real_write_file (%s): pos = %.0f, size = %lu, returned %ld\n",
 		fsp->fsp_name, (double)pos, (unsigned long)n, (long)ret ));
diff --git a/source3/smbd/vfs-wrap.c b/source3/smbd/vfs-wrap.c
index 378a0a1e53..4f2d82734f 100644
--- a/source3/smbd/vfs-wrap.c
+++ b/source3/smbd/vfs-wrap.c
@@ -44,10 +44,10 @@ void vfswrap_dummy_disconnect(vfs_handle_struct *handle, connection_struct *conn
 SMB_BIG_UINT vfswrap_disk_free(vfs_handle_struct *handle, connection_struct *conn, const char *path, BOOL small_query, SMB_BIG_UINT *bsize, 
 			       SMB_BIG_UINT *dfree, SMB_BIG_UINT *dsize)
 {
-    SMB_BIG_UINT result;
+	SMB_BIG_UINT result;
 
-    result = sys_disk_free(path, small_query, bsize, dfree, dsize);
-    return result;
+	result = sys_disk_free(path, small_query, bsize, dfree, dsize);
+	return result;
 }
 
 int vfswrap_get_quota(struct vfs_handle_struct *handle, struct connection_struct *conn, enum SMB_QUOTA_TYPE qtype, unid_t id, SMB_DISK_QUOTA *qt)
@@ -90,22 +90,22 @@ int vfswrap_get_shadow_copy_data(struct vfs_handle_struct *handle, struct files_
 
 DIR *vfswrap_opendir(vfs_handle_struct *handle, connection_struct *conn, const char *fname)
 {
-    DIR *result;
+	DIR *result;
 
-    START_PROFILE(syscall_opendir);
-    result = opendir(fname);
-    END_PROFILE(syscall_opendir);
-    return result;
+	START_PROFILE(syscall_opendir);
+	result = opendir(fname);
+	END_PROFILE(syscall_opendir);
+	return result;
 }
 
 struct dirent *vfswrap_readdir(vfs_handle_struct *handle, connection_struct *conn, DIR *dirp)
 {
-    struct dirent *result;
+	struct dirent *result;
 
-    START_PROFILE(syscall_readdir);
-    result = readdir(dirp);
-    END_PROFILE(syscall_readdir);
-    return result;
+	START_PROFILE(syscall_readdir);
+	result = readdir(dirp);
+	END_PROFILE(syscall_readdir);
+	return result;
 }
 
 int vfswrap_mkdir(vfs_handle_struct *handle, connection_struct *conn, const char *path, mode_t mode)
@@ -133,71 +133,154 @@ int vfswrap_mkdir(vfs_handle_struct *handle, connection_struct *conn, const char
 			errno = saved_errno;
 	}
 
-    END_PROFILE(syscall_mkdir);
-    return result;
+	END_PROFILE(syscall_mkdir);
+	return result;
 }
 
 int vfswrap_rmdir(vfs_handle_struct *handle, connection_struct *conn, const char *path)
 {
-    int result;
+	int result;
 
-    START_PROFILE(syscall_rmdir);
-    result = rmdir(path);
-    END_PROFILE(syscall_rmdir);
-    return result;
+	START_PROFILE(syscall_rmdir);
+	result = rmdir(path);
+	END_PROFILE(syscall_rmdir);
+	return result;
 }
 
 int vfswrap_closedir(vfs_handle_struct *handle, connection_struct *conn, DIR *dirp)
 {
-    int result;
+	int result;
 
-    START_PROFILE(syscall_closedir);
-    result = closedir(dirp);
-    END_PROFILE(syscall_closedir);
-    return result;
+	START_PROFILE(syscall_closedir);
+	result = closedir(dirp);
+	END_PROFILE(syscall_closedir);
+	return result;
 }
 
 /* File operations */
     
 int vfswrap_open(vfs_handle_struct *handle, connection_struct *conn, const char *fname, int flags, mode_t mode)
 {
-    int result;
+	int result;
 
-    START_PROFILE(syscall_open);
-    result = sys_open(fname, flags, mode);
-    END_PROFILE(syscall_open);
-    return result;
+	START_PROFILE(syscall_open);
+	result = sys_open(fname, flags, mode);
+	END_PROFILE(syscall_open);
+	return result;
 }
 
 int vfswrap_close(vfs_handle_struct *handle, files_struct *fsp, int fd)
 {
-    int result;
+	int result;
 
-    START_PROFILE(syscall_close);
+	START_PROFILE(syscall_close);
 
-    result = close(fd);
-    END_PROFILE(syscall_close);
-    return result;
+	result = close(fd);
+	END_PROFILE(syscall_close);
+	return result;
 }
 
 ssize_t vfswrap_read(vfs_handle_struct *handle, files_struct *fsp, int fd, void *data, size_t n)
 {
-    ssize_t result;
+	ssize_t result;
 
-    START_PROFILE_BYTES(syscall_read, n);
-    result = sys_read(fd, data, n);
-    END_PROFILE(syscall_read);
-    return result;
+	START_PROFILE_BYTES(syscall_read, n);
+	result = sys_read(fd, data, n);
+	END_PROFILE(syscall_read);
+	return result;
+}
+
+ssize_t vfswrap_pread(vfs_handle_struct *handle, files_struct *fsp, int fd, void *data,
+			size_t n, SMB_OFF_T offset)
+{
+	ssize_t result;
+
+#if defined(HAVE_PREAD) || defined(HAVE_PREAD64)
+	START_PROFILE_BYTES(syscall_pread, n);
+	result = sys_pread(fd, data, n, offset);
+	END_PROFILE(syscall_pread);
+ 
+	if (result == -1 && errno == ESPIPE) {
+		/* Maintain the fiction that pipes can be seeked (sought?) on. */
+		result = SMB_VFS_READ(fsp, fd, data, n);
+		fsp->pos = 0;
+	}
+
+#else /* HAVE_PREAD */
+	SMB_OFF_T   curr;
+	int lerrno;
+   
+	curr = SMB_VFS_LSEEK(fsp, fd, 0, SEEK_CUR);
+	if (curr == -1 && errno == ESPIPE) {
+		/* Maintain the fiction that pipes can be seeked (sought?) on. */
+		result = SMB_VFS_READ(fsp, fd, data, n);
+		fsp->pos = 0;
+		return result;
+	}
+
+	if (SMB_VFS_LSEEK(fsp, fd, offset, SEEK_SET) == -1) {
+		return -1;
+	}
+
+	errno = 0;
+	result = SMB_VFS_READ(fsp, fd, data, n);
+	lerrno = errno;
+
+	SMB_VFS_LSEEK(fsp, fd, curr, SEEK_SET);
+	errno = lerrno;
+
+#endif /* HAVE_PREAD */
+
+	return result;
 }
 
 ssize_t vfswrap_write(vfs_handle_struct *handle, files_struct *fsp, int fd, const void *data, size_t n)
 {
-    ssize_t result;
+	ssize_t result;
+
+	START_PROFILE_BYTES(syscall_write, n);
+	result = sys_write(fd, data, n);
+	END_PROFILE(syscall_write);
+	return result;
+}
+
+ssize_t vfswrap_pwrite(vfs_handle_struct *handle, files_struct *fsp, int fd, const void *data,
+			size_t n, SMB_OFF_T offset)
+{
+	ssize_t result;
+
+#if defined(HAVE_PWRITE) || defined(HAVE_PRWITE64)
+	START_PROFILE_BYTES(syscall_pwrite, n);
+	result = sys_pwrite(fd, data, n, offset);
+	END_PROFILE(syscall_pwrite);
+
+	if (result == -1 && errno == ESPIPE) {
+		/* Maintain the fiction that pipes can be sought on. */
+		result = SMB_VFS_WRITE(fsp, fd, data, n);
+	}
+
+#else /* HAVE_PWRITE */
+	SMB_OFF_T   curr;
+	int         lerrno;
 
-    START_PROFILE_BYTES(syscall_write, n);
-    result = sys_write(fd, data, n);
-    END_PROFILE(syscall_write);
-    return result;
+	curr = SMB_VFS_LSEEK(fsp, fd, 0, SEEK_CUR);
+	if (curr == -1) {
+		return -1;
+	}
+
+	if (SMB_VFS_LSEEK(fsp, fd, offset, SEEK_SET) == -1) {
+		return -1;
+	}
+
+	result = SMB_VFS_WRITE(fsp, fd, data, n);
+	lerrno = errno;
+
+	SMB_VFS_LSEEK(fsp, fd, curr, SEEK_SET);
+	errno = lerrno;
+
+#endif /* HAVE_PWRITE */
+
+	return result;
 }
 
 SMB_OFF_T vfswrap_lseek(vfs_handle_struct *handle, files_struct *fsp, int filedes, SMB_OFF_T offset, int whence)
@@ -340,13 +423,12 @@ int vfswrap_rename(vfs_handle_struct *handle, connection_struct *conn, const cha
 int vfswrap_fsync(vfs_handle_struct *handle, files_struct *fsp, int fd)
 {
 #ifdef HAVE_FSYNC
-    int result;
-
-    START_PROFILE(syscall_fsync);
+	int result;
 
-    result = fsync(fd);
-    END_PROFILE(syscall_fsync);
-    return result;
+	START_PROFILE(syscall_fsync);
+	result = fsync(fd);
+	END_PROFILE(syscall_fsync);
+	return result;
 #else
 	return 0;
 #endif
@@ -354,49 +436,49 @@ int vfswrap_fsync(vfs_handle_struct *handle, files_struct *fsp, int fd)
 
 int vfswrap_stat(vfs_handle_struct *handle, connection_struct *conn, const char *fname, SMB_STRUCT_STAT *sbuf)
 {
-    int result;
+	int result;
 
-    START_PROFILE(syscall_stat);
-    result = sys_stat(fname, sbuf);
-    END_PROFILE(syscall_stat);
-    return result;
+	START_PROFILE(syscall_stat);
+	result = sys_stat(fname, sbuf);
+	END_PROFILE(syscall_stat);
+	return result;
 }
 
 int vfswrap_fstat(vfs_handle_struct *handle, files_struct *fsp, int fd, SMB_STRUCT_STAT *sbuf)
 {
-    int result;
+	int result;
 
-    START_PROFILE(syscall_fstat);
-    result = sys_fstat(fd, sbuf);
-    END_PROFILE(syscall_fstat);
-    return result;
+	START_PROFILE(syscall_fstat);
+	result = sys_fstat(fd, sbuf);
+	END_PROFILE(syscall_fstat);
+	return result;
 }
 
 int vfswrap_lstat(vfs_handle_struct *handle, connection_struct *conn, const char *path, SMB_STRUCT_STAT *sbuf)
 {
-    int result;
+	int result;
 
-    START_PROFILE(syscall_lstat);
-    result = sys_lstat(path, sbuf);
-    END_PROFILE(syscall_lstat);
-    return result;
+	START_PROFILE(syscall_lstat);
+	result = sys_lstat(path, sbuf);
+	END_PROFILE(syscall_lstat);
+	return result;
 }
 
 int vfswrap_unlink(vfs_handle_struct *handle, connection_struct *conn, const char *path)
 {
-    int result;
+	int result;
 
-    START_PROFILE(syscall_unlink);
-    result = unlink(path);
-    END_PROFILE(syscall_unlink);
-    return result;
+	START_PROFILE(syscall_unlink);
+	result = unlink(path);
+	END_PROFILE(syscall_unlink);
+	return result;
 }
 
 int vfswrap_chmod(vfs_handle_struct *handle, connection_struct *conn, const char *path, mode_t mode)
 {
-    int result;
+	int result;
 
-    START_PROFILE(syscall_chmod);
+	START_PROFILE(syscall_chmod);
 
 	/*
 	 * We need to do this due to the fact that the default POSIX ACL
@@ -415,9 +497,9 @@ int vfswrap_chmod(vfs_handle_struct *handle, connection_struct *conn, const char
 		errno = saved_errno;
 	}
 
-    result = chmod(path, mode);
-    END_PROFILE(syscall_chmod);
-    return result;
+	result = chmod(path, mode);
+	END_PROFILE(syscall_chmod);
+	return result;
 }
 
 int vfswrap_fchmod(vfs_handle_struct *handle, files_struct *fsp, int fd, mode_t mode)
@@ -455,58 +537,57 @@ int vfswrap_fchmod(vfs_handle_struct *handle, files_struct *fsp, int fd, mode_t
 
 int vfswrap_chown(vfs_handle_struct *handle, connection_struct *conn, const char *path, uid_t uid, gid_t gid)
 {
-    int result;
+	int result;
 
-    START_PROFILE(syscall_chown);
-    result = sys_chown(path, uid, gid);
-    END_PROFILE(syscall_chown);
-    return result;
+	START_PROFILE(syscall_chown);
+	result = sys_chown(path, uid, gid);
+	END_PROFILE(syscall_chown);
+	return result;
 }
 
 int vfswrap_fchown(vfs_handle_struct *handle, files_struct *fsp, int fd, uid_t uid, gid_t gid)
 {
 #ifdef HAVE_FCHOWN
-    int result;
-
-    START_PROFILE(syscall_fchown);
+	int result;
 
-    result = fchown(fd, uid, gid);
-    END_PROFILE(syscall_fchown);
-    return result;
+	START_PROFILE(syscall_fchown);
+	result = fchown(fd, uid, gid);
+	END_PROFILE(syscall_fchown);
+	return result;
 #else
-    errno = ENOSYS;
-    return -1;
+	errno = ENOSYS;
+	return -1;
 #endif
 }
 
 int vfswrap_chdir(vfs_handle_struct *handle, connection_struct *conn, const char *path)
 {
-    int result;
+	int result;
 
-    START_PROFILE(syscall_chdir);
-    result = chdir(path);
-    END_PROFILE(syscall_chdir);
-    return result;
+	START_PROFILE(syscall_chdir);
+	result = chdir(path);
+	END_PROFILE(syscall_chdir);
+	return result;
 }
 
 char *vfswrap_getwd(vfs_handle_struct *handle, connection_struct *conn, char *path)
 {
-    char *result;
+	char *result;
 
-    START_PROFILE(syscall_getwd);
-    result = sys_getwd(path);
-    END_PROFILE(syscall_getwd);
-    return result;
+	START_PROFILE(syscall_getwd);
+	result = sys_getwd(path);
+	END_PROFILE(syscall_getwd);
+	return result;
 }
 
 int vfswrap_utime(vfs_handle_struct *handle, connection_struct *conn, const char *path, struct utimbuf *times)
 {
-    int result;
+	int result;
 
-    START_PROFILE(syscall_utime);
-    result = utime(path, times);
-    END_PROFILE(syscall_utime);
-    return result;
+	START_PROFILE(syscall_utime);
+	result = utime(path, times);
+	END_PROFILE(syscall_utime);
+	return result;
 }
 
 /*********************************************************************
@@ -643,33 +724,32 @@ int vfswrap_ftruncate(vfs_handle_struct *handle, files_struct *fsp, int fd, SMB_
 
 BOOL vfswrap_lock(vfs_handle_struct *handle, files_struct *fsp, int fd, int op, SMB_OFF_T offset, SMB_OFF_T count, int type)
 {
-    BOOL result;
-
-    START_PROFILE(syscall_fcntl_lock);
+	BOOL result;
 
-    result =  fcntl_lock(fd, op, offset, count,type);
-    END_PROFILE(syscall_fcntl_lock);
-    return result;
+	START_PROFILE(syscall_fcntl_lock);
+	result =  fcntl_lock(fd, op, offset, count,type);
+	END_PROFILE(syscall_fcntl_lock);
+	return result;
 }
 
 int vfswrap_symlink(vfs_handle_struct *handle, connection_struct *conn, const char *oldpath, const char *newpath)
 {
-    int result;
+	int result;
 
-    START_PROFILE(syscall_symlink);
-    result = sys_symlink(oldpath, newpath);
-    END_PROFILE(syscall_symlink);
-    return result;
+	START_PROFILE(syscall_symlink);
+	result = sys_symlink(oldpath, newpath);
+	END_PROFILE(syscall_symlink);
+	return result;
 }
 
 int vfswrap_readlink(vfs_handle_struct *handle, connection_struct *conn, const char *path, char *buf, size_t bufsiz)
 {
-    int result;
+	int result;
 
-    START_PROFILE(syscall_readlink);
-    result = sys_readlink(path, buf, bufsiz);
-    END_PROFILE(syscall_readlink);
-    return result;
+	START_PROFILE(syscall_readlink);
+	result = sys_readlink(path, buf, bufsiz);
+	END_PROFILE(syscall_readlink);
+	return result;
 }
 
 int vfswrap_link(vfs_handle_struct *handle, connection_struct *conn, const char *oldpath, const char *newpath)
diff --git a/source3/smbd/vfs.c b/source3/smbd/vfs.c
index 753db4cece..2f981c743f 100644
--- a/source3/smbd/vfs.c
+++ b/source3/smbd/vfs.c
@@ -71,7 +71,9 @@ static struct vfs_ops default_vfs = {
 		vfswrap_open,
 		vfswrap_close,
 		vfswrap_read,
+		vfswrap_pread,
 		vfswrap_write,
+		vfswrap_pwrite,
 		vfswrap_lseek,
 		vfswrap_sendfile,
 		vfswrap_rename,
@@ -429,6 +431,28 @@ ssize_t vfs_read_data(files_struct *fsp, char *buf, size_t byte_count)
 	return (ssize_t)total;
 }
 
+ssize_t vfs_pread_data(files_struct *fsp, char *buf,
+                size_t byte_count, SMB_OFF_T offset)
+{
+	size_t total=0;
+
+	while (total < byte_count)
+	{
+		ssize_t ret = SMB_VFS_PREAD(fsp, fsp->fd, buf + total,
+					byte_count - total, offset + total);
+
+		if (ret == 0) return total;
+		if (ret == -1) {
+			if (errno == EINTR)
+				continue;
+			else
+				return -1;
+		}
+		total += ret;
+	}
+	return (ssize_t)total;
+}
+
 /****************************************************************************
  Write data to a fd on the vfs.
 ****************************************************************************/
@@ -451,6 +475,25 @@ ssize_t vfs_write_data(files_struct *fsp,const char *buffer,size_t N)
 	return (ssize_t)total;
 }
 
+ssize_t vfs_pwrite_data(files_struct *fsp,const char *buffer,
+                size_t N, SMB_OFF_T offset)
+{
+	size_t total=0;
+	ssize_t ret;
+
+	while (total < N) {
+		ret = SMB_VFS_PWRITE(fsp, fsp->fd, buffer + total,
+                                N - total, offset + total);
+
+		if (ret == -1)
+			return -1;
+		if (ret == 0)
+			return total;
+
+		total += ret;
+	}
+	return (ssize_t)total;
+}
 /****************************************************************************
  An allocate file space call using the vfs interface.
  Allocates space for a file from a filedescriptor.