Archipelago » qemu

/*

 * QEMU low level functions

 *

 * Copyright (c) 2003 Fabrice Bellard

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

#include <stdlib.h>

#include <stdio.h>

#include <stdarg.h>

#include <stdbool.h>

#include <string.h>

#include <errno.h>

#include <unistd.h>

#include <fcntl.h>

/* Needed early for CONFIG_BSD etc. */

#include "config-host.h"

#if defined(CONFIG_MADVISE) || defined(CONFIG_POSIX_MADVISE)

#include <sys/mman.h>

#endif

#ifdef CONFIG_SOLARIS

#include <sys/types.h>

#include <sys/statvfs.h>

/* See MySQL bug #7156 (http://bugs.mysql.com/bug.php?id=7156) for

   discussion about Solaris header problems */

extern int madvise(caddr_t, size_t, int);

#endif

#include "qemu-common.h"

#include "trace.h"

#include "qemu/sockets.h"

#include "monitor/monitor.h"

static bool fips_enabled = false;

static const char *qemu_version = QEMU_VERSION;

int socket_set_cork(int fd, int v)

{

#if defined(SOL_TCP) && defined(TCP_CORK)

    return qemu_setsockopt(fd, SOL_TCP, TCP_CORK, &v, sizeof(v));

#else

    return 0;

#endif

}

int socket_set_nodelay(int fd)

{

    int v = 1;

    return qemu_setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &v, sizeof(v));

}

int qemu_madvise(void *addr, size_t len, int advice)

{

    if (advice == QEMU_MADV_INVALID) {

        errno = EINVAL;

        return -1;

    }

#if defined(CONFIG_MADVISE)

    return madvise(addr, len, advice);

#elif defined(CONFIG_POSIX_MADVISE)

    return posix_madvise(addr, len, advice);

#else

    errno = EINVAL;

    return -1;

#endif

}

#ifndef _WIN32

/*

 * Dups an fd and sets the flags

 */

static int qemu_dup_flags(int fd, int flags)

{

    int ret;

    int serrno;

    int dup_flags;

#ifdef F_DUPFD_CLOEXEC

    ret = fcntl(fd, F_DUPFD_CLOEXEC, 0);

#else

    ret = dup(fd);

    if (ret != -1) {

        qemu_set_cloexec(ret);

    }

#endif

    if (ret == -1) {

        goto fail;

    }

    dup_flags = fcntl(ret, F_GETFL);

    if (dup_flags == -1) {

        goto fail;

    }

    if ((flags & O_SYNC) != (dup_flags & O_SYNC)) {

        errno = EINVAL;

        goto fail;

    }

    /* Set/unset flags that we can with fcntl */

    if (fcntl(ret, F_SETFL, flags) == -1) {

        goto fail;

    }

    /* Truncate the file in the cases that open() would truncate it */

    if (flags & O_TRUNC ||

            ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))) {

        if (ftruncate(ret, 0) == -1) {

            goto fail;

        }

    }

    return ret;

fail:

    serrno = errno;

    if (ret != -1) {

        close(ret);

    }

    errno = serrno;

    return -1;

}

static int qemu_parse_fdset(const char *param)

{

    return qemu_parse_fd(param);

}

#endif

/*

 * Opens a file with FD_CLOEXEC set

 */

int qemu_open(const char *name, int flags, ...)

{

    int ret;

    int mode = 0;

#ifndef _WIN32

    const char *fdset_id_str;

    /* Attempt dup of fd from fd set */

    if (strstart(name, "/dev/fdset/", &fdset_id_str)) {

        int64_t fdset_id;

        int fd, dupfd;

        fdset_id = qemu_parse_fdset(fdset_id_str);

        if (fdset_id == -1) {

            errno = EINVAL;

            return -1;

        }

        fd = monitor_fdset_get_fd(fdset_id, flags);

        if (fd == -1) {

            return -1;

        }

        dupfd = qemu_dup_flags(fd, flags);

        if (dupfd == -1) {

            return -1;

        }

        ret = monitor_fdset_dup_fd_add(fdset_id, dupfd);

        if (ret == -1) {

            close(dupfd);

            errno = EINVAL;

            return -1;

        }

        return dupfd;

    }

#endif

    if (flags & O_CREAT) {

        va_list ap;

        va_start(ap, flags);

        mode = va_arg(ap, int);

        va_end(ap);

    }

#ifdef O_CLOEXEC

    ret = open(name, flags | O_CLOEXEC, mode);

#else

    ret = open(name, flags, mode);

    if (ret >= 0) {

        qemu_set_cloexec(ret);

    }

#endif

    return ret;

}

int qemu_close(int fd)

{

    int64_t fdset_id;

    /* Close fd that was dup'd from an fdset */

    fdset_id = monitor_fdset_dup_fd_find(fd);

    if (fdset_id != -1) {

        int ret;

        ret = close(fd);

        if (ret == 0) {

            monitor_fdset_dup_fd_remove(fd);

        }

        return ret;

    }

    return close(fd);

}

/*

 * A variant of write(2) which handles partial write.

 *

 * Return the number of bytes transferred.

 * Set errno if fewer than `count' bytes are written.

 *

 * This function don't work with non-blocking fd's.

 * Any of the possibilities with non-bloking fd's is bad:

 *   - return a short write (then name is wrong)

 *   - busy wait adding (errno == EAGAIN) to the loop

 */

ssize_t qemu_write_full(int fd, const void *buf, size_t count)

{

    ssize_t ret = 0;

    ssize_t total = 0;

    while (count) {

        ret = write(fd, buf, count);

        if (ret < 0) {

            if (errno == EINTR)

                continue;

            break;

        }

        count -= ret;

        buf += ret;

        total += ret;

    }

    return total;

}

/*

 * Opens a socket with FD_CLOEXEC set

 */

int qemu_socket(int domain, int type, int protocol)

{

    int ret;

#ifdef SOCK_CLOEXEC

    ret = socket(domain, type | SOCK_CLOEXEC, protocol);

    if (ret != -1 || errno != EINVAL) {

        return ret;

    }

#endif

    ret = socket(domain, type, protocol);

    if (ret >= 0) {

        qemu_set_cloexec(ret);

    }

    return ret;

}

/*

 * Accept a connection and set FD_CLOEXEC

 */

int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen)

{

    int ret;

#ifdef CONFIG_ACCEPT4

    ret = accept4(s, addr, addrlen, SOCK_CLOEXEC);

    if (ret != -1 || errno != ENOSYS) {

        return ret;

    }

#endif

    ret = accept(s, addr, addrlen);

    if (ret >= 0) {

        qemu_set_cloexec(ret);

    }

    return ret;

}

/*

 * A variant of send(2) which handles partial write.

 *

 * Return the number of bytes transferred, which is only

 * smaller than `count' if there is an error.

 *

 * This function won't work with non-blocking fd's.

 * Any of the possibilities with non-bloking fd's is bad:

 *   - return a short write (then name is wrong)

 *   - busy wait adding (errno == EAGAIN) to the loop

 */

ssize_t qemu_send_full(int fd, const void *buf, size_t count, int flags)

{

    ssize_t ret = 0;

    ssize_t total = 0;

    while (count) {

        ret = send(fd, buf, count, flags);

        if (ret < 0) {

            if (errno == EINTR) {

                continue;

            }

            break;

        }

        count -= ret;

        buf += ret;

        total += ret;

    }

    return total;

}

/*

 * A variant of recv(2) which handles partial write.

 *

 * Return the number of bytes transferred, which is only

 * smaller than `count' if there is an error.

 *

 * This function won't work with non-blocking fd's.

 * Any of the possibilities with non-bloking fd's is bad:

 *   - return a short write (then name is wrong)

 *   - busy wait adding (errno == EAGAIN) to the loop

 */

ssize_t qemu_recv_full(int fd, void *buf, size_t count, int flags)

{

    ssize_t ret = 0;

    ssize_t total = 0;

    while (count) {

        ret = qemu_recv(fd, buf, count, flags);

        if (ret <= 0) {

            if (ret < 0 && errno == EINTR) {

                continue;

            }

            break;

        }

        count -= ret;

        buf += ret;

        total += ret;

    }

    return total;

}

void qemu_set_version(const char *version)

{

    qemu_version = version;

}

const char *qemu_get_version(void)

{

    return qemu_version;

}

void fips_set_state(bool requested)

{

#ifdef __linux__

    if (requested) {

        FILE *fds = fopen("/proc/sys/crypto/fips_enabled", "r");

        if (fds != NULL) {

            fips_enabled = (fgetc(fds) == '1');

            fclose(fds);

        }

    }

#else

    fips_enabled = false;

#endif /* __linux__ */

#ifdef _FIPS_DEBUG

    fprintf(stderr, "FIPS mode %s (requested %s)\n",

            (fips_enabled ? "enabled" : "disabled"),

            (requested ? "enabled" : "disabled"));

#endif

}

bool fips_get_state(void)

{

    return fips_enabled;

}

#ifdef _WIN32

static void socket_cleanup(void)

{

    WSACleanup();

}

#endif

int socket_init(void)

{

#ifdef _WIN32

    WSADATA Data;

    int ret, err;

    ret = WSAStartup(MAKEWORD(2, 2), &Data);

    if (ret != 0) {

        err = WSAGetLastError();

        fprintf(stderr, "WSAStartup: %d\n", err);

        return -1;

    }

    atexit(socket_cleanup);

#endif

    return 0;

}

#ifndef CONFIG_IOVEC

/* helper function for iov_send_recv() */

static ssize_t

readv_writev(int fd, const struct iovec *iov, int iov_cnt, bool do_write)

{

    unsigned i = 0;

    ssize_t ret = 0;

    while (i < iov_cnt) {

        ssize_t r = do_write

            ? write(fd, iov[i].iov_base, iov[i].iov_len)

            : read(fd, iov[i].iov_base, iov[i].iov_len);

        if (r > 0) {

            ret += r;

        } else if (!r) {

            break;

        } else if (errno == EINTR) {

            continue;

        } else {

            /* else it is some "other" error,

             * only return if there was no data processed. */

            if (ret == 0) {

                ret = -1;

            }

            break;

        }

        i++;

    }

    return ret;

}

ssize_t

readv(int fd, const struct iovec *iov, int iov_cnt)

{

    return readv_writev(fd, iov, iov_cnt, false);

}

ssize_t

writev(int fd, const struct iovec *iov, int iov_cnt)

{

    return readv_writev(fd, iov, iov_cnt, true);

}

#endif