diff options
author | Michael Brown | 2012-06-09 19:48:09 +0200 |
---|---|---|
committer | Michael Brown | 2012-06-09 19:48:28 +0200 |
commit | 021d7b21b7f30a8de9ff56ae3a70026bafcdc542 (patch) | |
tree | 152dfd6bf7f7a8622014bd938e7b12a48ac47c2a /src/core/pending.c | |
parent | [cmdline] Add "cpuid" command (diff) | |
download | ipxe-021d7b21b7f30a8de9ff56ae3a70026bafcdc542.tar.gz ipxe-021d7b21b7f30a8de9ff56ae3a70026bafcdc542.tar.xz ipxe-021d7b21b7f30a8de9ff56ae3a70026bafcdc542.zip |
[pending] Add concept of "pending operations"
iPXE is fundamentally asynchronous in operation: some operations
continue in the background even after the foreground has continued to
a new task. For example, the closing FIN/ACK exchanges of a TCP
connection will take place in the background after an HTTP download
has completed.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Diffstat (limited to 'src/core/pending.c')
-rw-r--r-- | src/core/pending.c | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/src/core/pending.c b/src/core/pending.c new file mode 100644 index 00000000..da540fec --- /dev/null +++ b/src/core/pending.c @@ -0,0 +1,79 @@ +/* + * Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +FILE_LICENCE ( GPL2_OR_LATER ); + +#include <errno.h> +#include <ipxe/process.h> +#include <ipxe/timer.h> +#include <ipxe/pending.h> + +/** @file + * + * Pending operations + * + */ + +/** Total count of pending operations */ +static int pending_total; + +/** + * Mark an operation as pending + * + * @v pending Pending operation + */ +void pending_get ( struct pending_operation *pending ) { + + pending->count++; + pending_total++; + DBGC ( pending, "PENDING %p incremented to %d (total %d)\n", + pending, pending->count, pending_total ); +} + +/** + * Mark an operation as no longer pending + * + * @v pending Pending operation + */ +void pending_put ( struct pending_operation *pending ) { + + if ( pending->count ) { + pending_total--; + pending->count--; + DBGC ( pending, "PENDING %p decremented to %d (total %d)\n", + pending, pending->count, pending_total ); + } +} + +/** + * Wait for pending operations to complete + * + * @v timeout Timeout period, in ticks (0=indefinite) + * @ret rc Return status code + */ +int pending_wait ( unsigned long timeout ) { + unsigned long start = currticks(); + + do { + if ( pending_total == 0 ) + return 0; + step(); + } while ( ( timeout == 0 ) || ( ( currticks() - start ) < timeout ) ); + + return -ETIMEDOUT; +} |