resource.c

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/*
 * Copyright (C) 2004, 2007-2009  Internet Systems Consortium, Inc. ("ISC")
 * Copyright (C) 2000, 2001  Internet Software Consortium.
 *
 * 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 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.
 */

/* $Id: resource.c,v 1.23 2009/02/13 23:48:14 tbox Exp $ */

#include <config.h>

#include <sys/types.h>
#include <sys/time.h>   /* Required on some systems for <sys/resource.h>. */
#include <sys/resource.h>

#include <isc/platform.h>
#include <isc/resource.h>
#include <isc/result.h>
#include <isc/util.h>

#ifdef __linux__
#include <linux/fs.h>   /* To get the large NR_OPEN. */
#endif

#if defined(__hpux) && defined(HAVE_SYS_DYNTUNE_H)
#include <sys/dyntune.h>
#endif

#include "errno2result.h"

static isc_result_t
resource2rlim(isc_resource_t resource, int *rlim_resource) {
        isc_result_t result = ISC_R_SUCCESS;

        switch (resource) {
        case isc_resource_coresize:
                *rlim_resource = RLIMIT_CORE;
                break;
        case isc_resource_cputime:
                *rlim_resource = RLIMIT_CPU;
                break;
        case isc_resource_datasize:
                *rlim_resource = RLIMIT_DATA;
                break;
        case isc_resource_filesize:
                *rlim_resource = RLIMIT_FSIZE;
                break;
        case isc_resource_lockedmemory:
#ifdef RLIMIT_MEMLOCK
                *rlim_resource = RLIMIT_MEMLOCK;
#else
                result = ISC_R_NOTIMPLEMENTED;
#endif
                break;
        case isc_resource_openfiles:
#ifdef RLIMIT_NOFILE
                *rlim_resource = RLIMIT_NOFILE;
#else
                result = ISC_R_NOTIMPLEMENTED;
#endif
                break;
        case isc_resource_processes:
#ifdef RLIMIT_NPROC
                *rlim_resource = RLIMIT_NPROC;
#else
                result = ISC_R_NOTIMPLEMENTED;
#endif
                break;
        case isc_resource_residentsize:
#ifdef RLIMIT_RSS
                *rlim_resource = RLIMIT_RSS;
#else
                result = ISC_R_NOTIMPLEMENTED;
#endif
                break;
        case isc_resource_stacksize:
                *rlim_resource = RLIMIT_STACK;
                break;
        default:
                /*
                 * This test is not very robust if isc_resource_t
                 * changes, but generates a clear assertion message.
                 */
                REQUIRE(resource >= isc_resource_coresize &&
                        resource <= isc_resource_stacksize);

                result = ISC_R_RANGE;
                break;
        }

        return (result);
}

isc_result_t
isc_resource_setlimit(isc_resource_t resource, isc_resourcevalue_t value) {
        struct rlimit rl;
        ISC_PLATFORM_RLIMITTYPE rlim_value;
        int unixresult;
        int unixresource;
        isc_result_t result;

        result = resource2rlim(resource, &unixresource);
        if (result != ISC_R_SUCCESS)
                return (result);

        if (value == ISC_RESOURCE_UNLIMITED)
                rlim_value = RLIM_INFINITY;

        else {
                /*
                 * isc_resourcevalue_t was chosen as an unsigned 64 bit
                 * integer so that it could contain the maximum range of
                 * reasonable values.  Unfortunately, this exceeds the typical
                 * range on Unix systems.  Ensure the range of
                 * ISC_PLATFORM_RLIMITTYPE is not overflowed.
                 */
                isc_resourcevalue_t rlim_max;
                isc_boolean_t rlim_t_is_signed =
                        ISC_TF(((double)(ISC_PLATFORM_RLIMITTYPE)-1) < 0);

                if (rlim_t_is_signed)
                        rlim_max = ~((ISC_PLATFORM_RLIMITTYPE)1 <<
                                     (sizeof(ISC_PLATFORM_RLIMITTYPE) * 8 - 1));
                else
                        rlim_max = (ISC_PLATFORM_RLIMITTYPE)-1;

                if (value > rlim_max)
                        value = rlim_max;

                rlim_value = value;
        }

        rl.rlim_cur = rl.rlim_max = rlim_value;
        unixresult = setrlimit(unixresource, &rl);

        if (unixresult == 0)
                return (ISC_R_SUCCESS);

#if defined(OPEN_MAX) && defined(__APPLE__)
        /*
         * The Darwin kernel doesn't accept RLIM_INFINITY for rlim_cur; the
         * maximum possible value is OPEN_MAX.  BIND8 used to use
         * sysconf(_SC_OPEN_MAX) for such a case, but this value is much
         * smaller than OPEN_MAX and is not really effective.
         */
        if (resource == isc_resource_openfiles && rlim_value == RLIM_INFINITY) {
                rl.rlim_cur = OPEN_MAX;
                unixresult = setrlimit(unixresource, &rl);
                if (unixresult == 0)
                        return (ISC_R_SUCCESS);
        }
#elif defined(__linux__)
#ifndef NR_OPEN
#define NR_OPEN (1024*1024)
#endif

        /*
         * Some Linux kernels don't accept RLIM_INFINIT; the maximum
         * possible value is the NR_OPEN defined in linux/fs.h.
         */
        if (resource == isc_resource_openfiles && rlim_value == RLIM_INFINITY) {
                rl.rlim_cur = rl.rlim_max = NR_OPEN;
                unixresult = setrlimit(unixresource, &rl);
                if (unixresult == 0)
                        return (ISC_R_SUCCESS);
        }
#elif defined(__hpux) && defined(HAVE_SYS_DYNTUNE_H)
        if (resource == isc_resource_openfiles && rlim_value == RLIM_INFINITY) {
                uint64_t maxfiles;
                if (gettune("maxfiles_lim", &maxfiles) == 0) {
                        rl.rlim_cur = rl.rlim_max = maxfiles;
                        unixresult = setrlimit(unixresource, &rl);
                        if (unixresult == 0)
                                return (ISC_R_SUCCESS);
                }
        }
#endif
        if (resource == isc_resource_openfiles && rlim_value == RLIM_INFINITY) {
                if (getrlimit(unixresource, &rl) == 0) {
                        rl.rlim_cur = rl.rlim_max;
                        unixresult = setrlimit(unixresource, &rl);
                        if (unixresult == 0)
                                return (ISC_R_SUCCESS);
                }
        }
        return (isc__errno2result(errno));
}

isc_result_t
isc_resource_getlimit(isc_resource_t resource, isc_resourcevalue_t *value) {
        int unixresult;
        int unixresource;
        struct rlimit rl;
        isc_result_t result;

        result = resource2rlim(resource, &unixresource);
        if (result == ISC_R_SUCCESS) {
                unixresult = getrlimit(unixresource, &rl);
                INSIST(unixresult == 0);
                *value = rl.rlim_max;
        }

        return (result);
}

isc_result_t
isc_resource_getcurlimit(isc_resource_t resource, isc_resourcevalue_t *value) {
        int unixresult;
        int unixresource;
        struct rlimit rl;
        isc_result_t result;

        result = resource2rlim(resource, &unixresource);
        if (result == ISC_R_SUCCESS) {
                unixresult = getrlimit(unixresource, &rl);
                INSIST(unixresult == 0);
                *value = rl.rlim_cur;
        }

        return (result);
}

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