Coverage Report

Created: 2025-07-01 06:50

/src/openvswitch/lib/syslog-direct.c
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Source (jump to first uncovered line)
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/*
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 * Copyright (c) 2015 Nicira, Inc.
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 *
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 * Licensed under the Apache License, Version 2.0 (the "License");
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 * you may not use this file except in compliance with the License.
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 * You may obtain a copy of the License at:
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 *
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 *     http://www.apache.org/licenses/LICENSE-2.0
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 *
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 * Unless required by applicable law or agreed to in writing, software
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 * distributed under the License is distributed on an "AS IS" BASIS,
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 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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 * See the License for the specific language governing permissions and
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 * limitations under the License.
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 */
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#include "syslog-direct.h"
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#include <config.h>
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#include <string.h>
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#include <unistd.h>
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#include "compiler.h"
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#include "openvswitch/dynamic-string.h"
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#include "socket-util.h"
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#include "syslog-provider.h"
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#include "util.h"
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#define FACILITY_MASK 0x03f8
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static void syslog_direct_open(struct syslogger *this, int facility);
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static void syslog_direct_log(struct syslogger *this, int pri,
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                              const char *msg);
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static struct syslog_class syslog_direct_class = {
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    syslog_direct_open,
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    syslog_direct_log,
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};
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struct syslog_direct {
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    struct syslogger parent;
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    int fd;  /* Negative number in error case.  Otherwise, socket. */
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    int facility;
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};
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/* This function creates object that directly interacts with syslog over
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 * UDP or Unix domain socket specified in 'method'. */
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struct syslogger *
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syslog_direct_create(const char *method)
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{
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    struct syslog_direct *this = xmalloc(sizeof *this);
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    this->parent.class = &syslog_direct_class;
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    this->parent.prefix = "<%B>";
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    /* socket is created from here (opposed to syslog_direct_open())
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     * so that deadlocks would be avoided.  The problem is that these
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     * functions that create socket might call VLOG() */
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    if (!strncmp(method, "udp:", 4)) {
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        inet_open_active(SOCK_DGRAM, &method[4], 514, NULL, &this->fd, 0);
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    } else if (!strncmp(method, "unix:", 5)) {
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        this->fd = make_unix_socket(SOCK_DGRAM, true, NULL, &method[5]);
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    } else {
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        this->fd = -1;
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    }
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    return &this->parent;
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}
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static void
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syslog_direct_open(struct syslogger *this, int facility)
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0
{
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    struct syslog_direct *this_ = (struct syslog_direct*) this;
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    this_->facility = facility;
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}
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static void
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syslog_direct_log(struct syslogger *this, int pri, const char *msg)
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{
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    static size_t max_len = SIZE_MAX; /* max message size we have discovered
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                                       * to be able to send() without failing
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                                       * with EMSGSIZE. */
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    struct syslog_direct *this_ = (struct syslog_direct*) this;
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    struct ds ds = DS_EMPTY_INITIALIZER;
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    const char *wire_msg;
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    size_t send_len;
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    if (this_->fd < 0) {
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        /* Failed to open socket for logging. */
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        return;
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    }
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    if (!(pri & FACILITY_MASK)) {
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        pri |= this_->facility;
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    }
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    ds_put_format(&ds, "<%u>%s", pri, msg);
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    wire_msg = ds_cstr(&ds);
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    send_len = MIN(strlen(wire_msg), max_len);
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    while (send(this_->fd, wire_msg, send_len, 0) < 0 && errno == EMSGSIZE) {
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        /* If message was too large for send() function then try to discover
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         * max_len supported for this particular socket and retry sending a
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         * truncated version of the same message. */
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        send_len -= send_len / 20;
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        max_len = send_len;
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    }
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    ds_destroy(&ds);
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0
}