diff options
Diffstat (limited to 'src/ccapi/server/ccs_lock.c')
| -rw-r--r-- | src/ccapi/server/ccs_lock.c | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/src/ccapi/server/ccs_lock.c b/src/ccapi/server/ccs_lock.c new file mode 100644 index 000000000..939da5e12 --- /dev/null +++ b/src/ccapi/server/ccs_lock.c @@ -0,0 +1,245 @@ +/* + * $Header$ + * + * Copyright 2006 Massachusetts Institute of Technology. + * All Rights Reserved. + * + * Export of this software from the United States of America may + * require a specific license from the United States Government. + * It is the responsibility of any person or organization contemplating + * export to obtain such a license before exporting. + * + * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and + * distribute this software and its documentation for any purpose and + * without fee is hereby granted, provided that the above copyright + * notice appear in all copies and that both that copyright notice and + * this permission notice appear in supporting documentation, and that + * the name of M.I.T. not be used in advertising or publicity pertaining + * to distribution of the software without specific, written prior + * permission. Furthermore if you modify this software you must label + * your software as modified software and not distribute it in such a + * fashion that it might be confused with the original M.I.T. software. + * M.I.T. makes no representations about the suitability of + * this software for any purpose. It is provided "as is" without express + * or implied warranty. + */ + +#include "ccs_common.h" + +struct ccs_lock_d { + cc_uint32 type; + cc_uint32 pending; + cc_int32 invalid_object_err; + ccs_pipe_t client_pipe; + ccs_pipe_t reply_pipe; +}; + +struct ccs_lock_d ccs_lock_initializer = { 0, 1, 1, NULL, NULL }; + +/* ------------------------------------------------------------------------ */ + +cc_int32 ccs_lock_new (ccs_lock_t *out_lock, + cc_uint32 in_type, + cc_int32 in_invalid_object_err, + ccs_pipe_t in_client_pipe, + ccs_pipe_t in_reply_pipe) +{ + cc_int32 err = ccNoError; + ccs_lock_t lock = NULL; + + if (!out_lock ) { err = cci_check_error (ccErrBadParam); } + if (!ccs_pipe_valid (in_client_pipe)) { err = cci_check_error (ccErrBadParam); } + if (!ccs_pipe_valid (in_reply_pipe) ) { err = cci_check_error (ccErrBadParam); } + + if (in_type != cc_lock_read && + in_type != cc_lock_write && + in_type != cc_lock_upgrade && + in_type != cc_lock_downgrade) { + err = cci_check_error (ccErrBadLockType); + } + + if (!err) { + lock = malloc (sizeof (*lock)); + if (lock) { + *lock = ccs_lock_initializer; + } else { + err = cci_check_error (ccErrNoMem); + } + } + + if (!err) { + err = ccs_pipe_copy (&lock->client_pipe, in_client_pipe); + } + + if (!err) { + err = ccs_pipe_copy (&lock->reply_pipe, in_reply_pipe); + } + + if (!err) { + lock->type = in_type; + lock->invalid_object_err = in_invalid_object_err; + + *out_lock = lock; + lock = NULL; + } + + ccs_lock_release (lock); + + return cci_check_error (err); +} + +/* ------------------------------------------------------------------------ */ + +cc_int32 ccs_lock_release (ccs_lock_t io_lock) +{ + cc_int32 err = ccNoError; + + if (!io_lock) { err = cci_check_error (ccErrBadParam); } + + if (!err && io_lock->pending) { + err = ccs_server_send_reply (io_lock->reply_pipe, + io_lock->invalid_object_err, NULL); + } + + if (!err) { + ccs_pipe_release (io_lock->client_pipe); + ccs_pipe_release (io_lock->reply_pipe); + free (io_lock); + } + + return cci_check_error (err); +} + +/* ------------------------------------------------------------------------ */ + +cc_int32 ccs_lock_grant_lock (ccs_lock_t io_lock) +{ + cc_int32 err = ccNoError; + + if (!io_lock) { err = cci_check_error (ccErrBadParam); } + + if (!err) { + if (io_lock->pending) { + err = ccs_server_send_reply (io_lock->reply_pipe, err, NULL); + + if (!err) { + ccs_pipe_release (io_lock->reply_pipe); + io_lock->pending = 0; + io_lock->reply_pipe = NULL; + } + } else { + cci_debug_printf ("WARNING %s() called on non-pending lock!", + __FUNCTION__); + } + } + + return cci_check_error (err); +} + +/* ------------------------------------------------------------------------ */ + +cc_uint32 ccs_lock_is_pending (ccs_lock_t in_lock, + cc_uint32 *out_pending) +{ + cc_int32 err = ccNoError; + + if (!in_lock ) { err = cci_check_error (ccErrBadParam); } + if (!out_pending) { err = cci_check_error (ccErrBadParam); } + + if (!err) { + *out_pending = in_lock->pending; + } + + return cci_check_error (err); +} + +/* ------------------------------------------------------------------------ */ + +cc_int32 ccs_lock_type (ccs_lock_t in_lock, + cc_uint32 *out_lock_type) +{ + cc_int32 err = ccNoError; + + if (!in_lock ) { err = cci_check_error (ccErrBadParam); } + if (!out_lock_type) { err = cci_check_error (ccErrBadParam); } + + if (!err) { + *out_lock_type = in_lock->type; + } + + return cci_check_error (err); +} + +/* ------------------------------------------------------------------------ */ + +cc_int32 ccs_lock_is_read_lock (ccs_lock_t in_lock, + cc_uint32 *out_is_read_lock) +{ + cc_int32 err = ccNoError; + + if (!in_lock ) { err = cci_check_error (ccErrBadParam); } + if (!out_is_read_lock) { err = cci_check_error (ccErrBadParam); } + + if (!err) { + *out_is_read_lock = (in_lock->type == cc_lock_read || + in_lock->type == cc_lock_downgrade); + } + + return cci_check_error (err); +} + +/* ------------------------------------------------------------------------ */ + +cc_int32 ccs_lock_is_write_lock (ccs_lock_t in_lock, + cc_uint32 *out_is_write_lock) +{ + cc_int32 err = ccNoError; + + if (!in_lock ) { err = cci_check_error (ccErrBadParam); } + if (!out_is_write_lock) { err = cci_check_error (ccErrBadParam); } + + if (!err) { + *out_is_write_lock = (in_lock->type == cc_lock_write || + in_lock->type == cc_lock_upgrade); + } + + return cci_check_error (err); +} + +/* ------------------------------------------------------------------------ */ + +cc_int32 ccs_lock_is_for_client (ccs_lock_t in_lock, + ccs_pipe_t in_client_pipe, + cc_uint32 *out_is_for_client) +{ + cc_int32 err = ccNoError; + + if (!in_lock ) { err = cci_check_error (ccErrBadParam); } + if (!out_is_for_client ) { err = cci_check_error (ccErrBadParam); } + if (!ccs_pipe_valid (in_client_pipe)) { err = cci_check_error (ccErrBadParam); } + + if (!err) { + err = ccs_pipe_compare (in_lock->client_pipe, in_client_pipe, + out_is_for_client); + } + + return cci_check_error (err); +} + + +/* ------------------------------------------------------------------------ */ + +cc_int32 ccs_lock_client (ccs_lock_t in_lock, + ccs_pipe_t *out_client_pipe) +{ + cc_int32 err = ccNoError; + + if (!in_lock ) { err = cci_check_error (ccErrBadParam); } + if (!out_client_pipe) { err = cci_check_error (ccErrBadParam); } + + if (!err) { + *out_client_pipe = in_lock->client_pipe; + } + + return cci_check_error (err); +} |