diff options
Diffstat (limited to 'lib/isccc/ccmsg.c')
| -rw-r--r-- | lib/isccc/ccmsg.c | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/lib/isccc/ccmsg.c b/lib/isccc/ccmsg.c new file mode 100644 index 0000000..9ee48ab --- /dev/null +++ b/lib/isccc/ccmsg.c @@ -0,0 +1,185 @@ +/* + * Copyright (C) Internet Systems Consortium, Inc. ("ISC") + * + * SPDX-License-Identifier: MPL-2.0 AND ISC + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, you can obtain one at https://mozilla.org/MPL/2.0/. + * + * See the COPYRIGHT file distributed with this work for additional + * information regarding copyright ownership. + */ + +/* + * Copyright (C) 2001 Nominum, Inc. + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND ISC AND NOMINUM DISCLAIMS ALL + * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY + * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +/*! \file */ + +#include <inttypes.h> + +#include <isc/mem.h> +#include <isc/netmgr.h> +#include <isc/result.h> +#include <isc/string.h> +#include <isc/util.h> + +#include <isccc/ccmsg.h> +#include <isccc/events.h> + +#define CCMSG_MAGIC ISC_MAGIC('C', 'C', 'm', 's') +#define VALID_CCMSG(foo) ISC_MAGIC_VALID(foo, CCMSG_MAGIC) + +static void +recv_data(isc_nmhandle_t *handle, isc_result_t eresult, isc_region_t *region, + void *arg) { + isccc_ccmsg_t *ccmsg = arg; + size_t size; + + INSIST(VALID_CCMSG(ccmsg)); + + switch (eresult) { + case ISC_R_SHUTTINGDOWN: + case ISC_R_CANCELED: + case ISC_R_EOF: + ccmsg->result = eresult; + goto done; + case ISC_R_SUCCESS: + if (region == NULL) { + ccmsg->result = ISC_R_EOF; + goto done; + } + ccmsg->result = ISC_R_SUCCESS; + break; + default: + ccmsg->result = eresult; + goto done; + } + + if (!ccmsg->length_received) { + if (region->length < sizeof(uint32_t)) { + ccmsg->result = ISC_R_UNEXPECTEDEND; + goto done; + } + + ccmsg->size = ntohl(*(uint32_t *)region->base); + + if (ccmsg->size == 0) { + ccmsg->result = ISC_R_UNEXPECTEDEND; + goto done; + } + if (ccmsg->size > ccmsg->maxsize) { + ccmsg->result = ISC_R_RANGE; + goto done; + } + + isc_region_consume(region, sizeof(uint32_t)); + isc_buffer_allocate(ccmsg->mctx, &ccmsg->buffer, ccmsg->size); + + ccmsg->length_received = true; + } + + /* + * If there's no more data, wait for more + */ + if (region->length == 0) { + return; + } + + /* We have some data in the buffer, read it */ + + size = ISC_MIN(isc_buffer_availablelength(ccmsg->buffer), + region->length); + isc_buffer_putmem(ccmsg->buffer, region->base, size); + isc_region_consume(region, size); + + if (isc_buffer_usedlength(ccmsg->buffer) == ccmsg->size) { + ccmsg->result = ISC_R_SUCCESS; + goto done; + } + + /* Wait for more data to come */ + return; + +done: + isc_nm_pauseread(handle); + ccmsg->cb(handle, ccmsg->result, ccmsg->cbarg); +} + +void +isccc_ccmsg_init(isc_mem_t *mctx, isc_nmhandle_t *handle, + isccc_ccmsg_t *ccmsg) { + REQUIRE(mctx != NULL); + REQUIRE(handle != NULL); + REQUIRE(ccmsg != NULL); + + *ccmsg = (isccc_ccmsg_t){ + .magic = CCMSG_MAGIC, + .maxsize = 0xffffffffU, /* Largest message possible. */ + .mctx = mctx, + .handle = handle, + .result = ISC_R_UNEXPECTED /* None yet. */ + }; +} + +void +isccc_ccmsg_setmaxsize(isccc_ccmsg_t *ccmsg, unsigned int maxsize) { + REQUIRE(VALID_CCMSG(ccmsg)); + + ccmsg->maxsize = maxsize; +} + +void +isccc_ccmsg_readmessage(isccc_ccmsg_t *ccmsg, isc_nm_cb_t cb, void *cbarg) { + REQUIRE(VALID_CCMSG(ccmsg)); + + if (ccmsg->buffer != NULL) { + isc_buffer_free(&ccmsg->buffer); + } + + ccmsg->cb = cb; + ccmsg->cbarg = cbarg; + ccmsg->result = ISC_R_UNEXPECTED; /* unknown right now */ + ccmsg->length_received = false; + + if (ccmsg->reading) { + isc_nm_resumeread(ccmsg->handle); + } else { + isc_nm_read(ccmsg->handle, recv_data, ccmsg); + ccmsg->reading = true; + } +} + +void +isccc_ccmsg_cancelread(isccc_ccmsg_t *ccmsg) { + REQUIRE(VALID_CCMSG(ccmsg)); + + if (ccmsg->reading) { + isc_nm_cancelread(ccmsg->handle); + ccmsg->reading = false; + } +} + +void +isccc_ccmsg_invalidate(isccc_ccmsg_t *ccmsg) { + REQUIRE(VALID_CCMSG(ccmsg)); + + ccmsg->magic = 0; + + if (ccmsg->buffer != NULL) { + isc_buffer_free(&ccmsg->buffer); + } +} |