util.c 79.2 KB
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/*
 * utils.c: common, generic utility functions
 *
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 * Copyright (C) 2006-2011 Red Hat, Inc.
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 * Copyright (C) 2006 Daniel P. Berrange
 * Copyright (C) 2006, 2007 Binary Karma
 * Copyright (C) 2006 Shuveb Hussain
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA
 *
 * Author: Daniel P. Berrange <berrange@redhat.com>
 * File created Jul 18, 2007 - Shuveb Hussain <shuveb@binarykarma.com>
 */

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#include <config.h>
28

29 30
#include <stdio.h>
#include <stdarg.h>
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#include <stdlib.h>
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#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
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#include <poll.h>
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#include <time.h>
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#include <sys/types.h>
#include <sys/stat.h>
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#include <sys/ioctl.h>
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#include <sys/wait.h>
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#include <sys/time.h>
42
#if HAVE_MMAP
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# include <sys/mman.h>
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#endif
45
#include <string.h>
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#include <signal.h>
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#include <termios.h>
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#if HAVE_LIBDEVMAPPER_H
# include <libdevmapper.h>
#endif
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#include "c-ctype.h"
52

53
#ifdef HAVE_PATHS_H
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# include <paths.h>
55
#endif
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#include <netdb.h>
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#ifdef HAVE_GETPWUID_R
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# include <pwd.h>
# include <grp.h>
60
#endif
61
#if HAVE_CAPNG
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# include <cap-ng.h>
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#endif
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#if defined HAVE_MNTENT_H && defined HAVE_GETMNTENT_R
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# include <mntent.h>
66
#endif
67

68
#include "dirname.h"
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#include "virterror_internal.h"
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#include "logging.h"
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#include "event.h"
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#include "ignore-value.h"
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#include "buf.h"
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#include "util.h"
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#include "memory.h"
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#include "threads.h"
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#include "verify.h"
78
#include "files.h"
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#include "command.h"
80
#include "nonblocking.h"
81
#include "passfd.h"
82

83 84 85 86
#ifndef NSIG
# define NSIG 32
#endif

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verify(sizeof(gid_t) <= sizeof (unsigned int) &&
       sizeof(uid_t) <= sizeof (unsigned int));

90
#define VIR_FROM_THIS VIR_FROM_NONE
91

92
#define virUtilError(code, ...)                                            \
93
        virReportErrorHelper(VIR_FROM_NONE, code, __FILE__,                \
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                             __FUNCTION__, __LINE__, __VA_ARGS__)
95

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/* Like read(), but restarts after EINTR */
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ssize_t
saferead(int fd, void *buf, size_t count)
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{
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    size_t nread = 0;
    while (count > 0) {
        ssize_t r = read(fd, buf, count);
        if (r < 0 && errno == EINTR)
            continue;
        if (r < 0)
            return r;
        if (r == 0)
            return nread;
        buf = (char *)buf + r;
        count -= r;
        nread += r;
    }
    return nread;
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}

/* Like write(), but restarts after EINTR */
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ssize_t
safewrite(int fd, const void *buf, size_t count)
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{
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    size_t nwritten = 0;
    while (count > 0) {
        ssize_t r = write(fd, buf, count);

        if (r < 0 && errno == EINTR)
            continue;
        if (r < 0)
            return r;
        if (r == 0)
            return nwritten;
        buf = (const char *)buf + r;
        count -= r;
        nwritten += r;
    }
    return nwritten;
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}

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#ifdef HAVE_POSIX_FALLOCATE
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int safezero(int fd, int flags ATTRIBUTE_UNUSED, off_t offset, off_t len)
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{
    return posix_fallocate(fd, offset, len);
}
#else

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# ifdef HAVE_MMAP
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int safezero(int fd, int flags ATTRIBUTE_UNUSED, off_t offset, off_t len)
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{
    int r;
    char *buf;

    /* memset wants the mmap'ed file to be present on disk so create a
     * sparse file
     */
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    r = ftruncate(fd, offset + len);
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    if (r < 0)
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        return -1;
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    buf = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_SHARED, fd, offset);
    if (buf == MAP_FAILED)
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        return -1;
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    memset(buf, 0, len);
    munmap(buf, len);

    return 0;
}

167
# else /* HAVE_MMAP */
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169
int safezero(int fd, int flags ATTRIBUTE_UNUSED, off_t offset, off_t len)
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{
    int r;
    char *buf;
    unsigned long long remain, bytes;

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    if (lseek(fd, offset, SEEK_SET) < 0)
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        return -1;
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    /* Split up the write in small chunks so as not to allocate lots of RAM */
    remain = len;
    bytes = 1024 * 1024;

    r = VIR_ALLOC_N(buf, bytes);
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    if (r < 0) {
        errno = ENOMEM;
        return -1;
    }
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    while (remain) {
        if (bytes > remain)
            bytes = remain;

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        r = safewrite(fd, buf, bytes);
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        if (r < 0) {
            VIR_FREE(buf);
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            return -1;
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        }

        /* safewrite() guarantees all data will be written */
        remain -= bytes;
    }
    VIR_FREE(buf);
    return 0;
}
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# endif /* HAVE_MMAP */
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#endif /* HAVE_POSIX_FALLOCATE */

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int virFileStripSuffix(char *str,
                       const char *suffix)
{
    int len = strlen(str);
    int suffixlen = strlen(suffix);

    if (len < suffixlen)
        return 0;

    if (!STREQ(str + len - suffixlen, suffix))
        return 0;

    str[len-suffixlen] = '\0';

    return 1;
}

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char *
virArgvToString(const char *const *argv)
{
    int len, i;
    char *ret, *p;

    for (len = 1, i = 0; argv[i]; i++)
        len += strlen(argv[i]) + 1;

    if (VIR_ALLOC_N(ret, len) < 0)
        return NULL;
    p = ret;

    for (i = 0; argv[i]; i++) {
        if (i != 0)
            *(p++) = ' ';

        strcpy(p, argv[i]);
        p += strlen(argv[i]);
    }

    *p = '\0';

    return ret;
}

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int virSetBlocking(int fd, bool blocking) {
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    return set_nonblocking_flag (fd, !blocking);
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}

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int virSetNonBlock(int fd) {
    return virSetBlocking(fd, false);
}

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int virSetCloseExec(int fd)
{
    return virSetInherit(fd, false);
}

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#ifndef WIN32
265

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int virSetInherit(int fd, bool inherit) {
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    int flags;
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    if ((flags = fcntl(fd, F_GETFD)) < 0)
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        return -1;
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    if (inherit)
        flags &= ~FD_CLOEXEC;
    else
        flags |= FD_CLOEXEC;
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    if ((fcntl(fd, F_SETFD, flags)) < 0)
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        return -1;
    return 0;
}

279

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# if HAVE_CAPNG
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static int virClearCapabilities(void)
{
    int ret;

    capng_clear(CAPNG_SELECT_BOTH);

    if ((ret = capng_apply(CAPNG_SELECT_BOTH)) < 0) {
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        virUtilError(VIR_ERR_INTERNAL_ERROR,
                     _("cannot clear process capabilities %d"), ret);
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        return -1;
    }

    return 0;
}
295
# else
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static int virClearCapabilities(void)
{
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//    VIR_WARN("libcap-ng support not compiled in, unable to clear capabilities");
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    return 0;
}
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# endif
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/* virFork() - fork a new process while avoiding various race/deadlock conditions

   @pid - a pointer to a pid_t that will receive the return value from
          fork()

   on return from virFork(), if *pid < 0, the fork failed and there is
   no new process. Otherwise, just like fork(), if *pid == 0, it is the
   child process returning, and if *pid > 0, it is the parent.

   Even if *pid >= 0, if the return value from virFork() is < 0, it
   indicates a failure that occurred in the parent or child process
   after the fork. In this case, the child process should call
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   _exit(EXIT_FAILURE) after doing any additional error reporting.
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 */
int virFork(pid_t *pid) {
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# ifdef HAVE_PTHREAD_SIGMASK
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    sigset_t oldmask, newmask;
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# endif
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    struct sigaction sig_action;
    int saved_errno, ret = -1;

    *pid = -1;

    /*
     * Need to block signals now, so that child process can safely
     * kill off caller's signal handlers without a race.
     */
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# ifdef HAVE_PTHREAD_SIGMASK
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    sigfillset(&newmask);
    if (pthread_sigmask(SIG_SETMASK, &newmask, &oldmask) != 0) {
        saved_errno = errno;
        virReportSystemError(errno,
                             "%s", _("cannot block signals"));
        goto cleanup;
    }
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# endif
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    /* Ensure we hold the logging lock, to protect child processes
     * from deadlocking on another thread's inherited mutex state */
    virLogLock();

    *pid = fork();
    saved_errno = errno; /* save for caller */

    /* Unlock for both parent and child process */
    virLogUnlock();

    if (*pid < 0) {
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# ifdef HAVE_PTHREAD_SIGMASK
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        /* attempt to restore signal mask, but ignore failure, to
           avoid obscuring the fork failure */
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        ignore_value (pthread_sigmask(SIG_SETMASK, &oldmask, NULL));
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# endif
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        virReportSystemError(saved_errno,
                             "%s", _("cannot fork child process"));
        goto cleanup;
    }

    if (*pid) {

        /* parent process */

367
# ifdef HAVE_PTHREAD_SIGMASK
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        /* Restore our original signal mask now that the child is
           safely running */
        if (pthread_sigmask(SIG_SETMASK, &oldmask, NULL) != 0) {
            saved_errno = errno; /* save for caller */
            virReportSystemError(errno, "%s", _("cannot unblock signals"));
            goto cleanup;
        }
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# endif
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        ret = 0;

    } else {

        /* child process */

        int logprio;
        int i;

        /* Remove any error callback so errors in child now
           get sent to stderr where they stand a fighting chance
           of being seen / logged */
        virSetErrorFunc(NULL, NULL);
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        virSetErrorLogPriorityFunc(NULL);
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        /* Make sure any hook logging is sent to stderr, since child
         * process may close the logfile FDs */
        logprio = virLogGetDefaultPriority();
        virLogReset();
        virLogSetDefaultPriority(logprio);

        /* Clear out all signal handlers from parent so nothing
           unexpected can happen in our child once we unblock
           signals */
        sig_action.sa_handler = SIG_DFL;
        sig_action.sa_flags = 0;
        sigemptyset(&sig_action.sa_mask);

        for (i = 1; i < NSIG; i++) {
            /* Only possible errors are EFAULT or EINVAL
               The former wont happen, the latter we
               expect, so no need to check return value */

            sigaction(i, &sig_action, NULL);
        }

412
# ifdef HAVE_PTHREAD_SIGMASK
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        /* Unmask all signals in child, since we've no idea
           what the caller's done with their signal mask
           and don't want to propagate that to children */
        sigemptyset(&newmask);
        if (pthread_sigmask(SIG_SETMASK, &newmask, NULL) != 0) {
            saved_errno = errno; /* save for caller */
            virReportSystemError(errno, "%s", _("cannot unblock signals"));
            goto cleanup;
        }
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# endif
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        ret = 0;
    }

cleanup:
    if (ret < 0)
        errno = saved_errno;
    return ret;
}

432 433
/*
 * @argv argv to exec
434
 * @envp optional environment to use for exec
435 436 437 438 439 440 441 442 443 444 445
 * @keepfd options fd_ret to keep open for child process
 * @retpid optional pointer to store child process pid
 * @infd optional file descriptor to use as child input, otherwise /dev/null
 * @outfd optional pointer to communicate output fd behavior
 *        outfd == NULL : Use /dev/null
 *        *outfd == -1  : Use a new fd
 *        *outfd != -1  : Use *outfd
 * @errfd optional pointer to communcate error fd behavior. See outfd
 * @flags possible combination of the following:
 *        VIR_EXEC_NONE     : Default function behavior
 *        VIR_EXEC_NONBLOCK : Set child process output fd's as non-blocking
446
 *        VIR_EXEC_DAEMON   : Daemonize the child process
447 448
 * @hook optional virExecHook function to call prior to exec
 * @data data to pass to the hook function
449
 * @pidfile path to use as pidfile for daemonized process (needs DAEMON flag)
450
 */
451 452
int
virExecWithHook(const char *const*argv,
453 454
          const char *const*envp,
          const fd_set *keepfd,
455
          pid_t *retpid,
456
          int infd, int *outfd, int *errfd,
457 458
          int flags,
          virExecHook hook,
459 460
          void *data,
          char *pidfile)
461
{
462 463
    pid_t pid;
    int null, i, openmax;
464 465
    int pipeout[2] = {-1,-1};
    int pipeerr[2] = {-1,-1};
466 467
    int childout = -1;
    int childerr = -1;
468
    int tmpfd;
469
    const char *binary = NULL;
470
    int forkRet;
471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490
    char *argv_str = NULL;
    char *envp_str = NULL;

    if ((argv_str = virArgvToString(argv)) == NULL) {
        virReportOOMError();
        return -1;
    }

    if (envp) {
        if ((envp_str = virArgvToString(envp)) == NULL) {
            VIR_FREE(argv_str);
            virReportOOMError();
            return -1;
        }
        VIR_DEBUG("%s %s", envp_str, argv_str);
        VIR_FREE(envp_str);
    } else {
        VIR_DEBUG("%s", argv_str);
    }
    VIR_FREE(argv_str);
491 492 493 494 495 496 497 498 499 500 501

    if (argv[0][0] != '/') {
        if (!(binary = virFindFileInPath(argv[0]))) {
            virReportSystemError(ENOENT,
                                 _("Cannot find '%s' in path"),
                                 argv[0]);
            return -1;
        }
    } else {
        binary = argv[0];
    }
502

503
    if ((null = open("/dev/null", O_RDWR)) < 0) {
504
        virReportSystemError(errno,
505 506
                             _("cannot open %s"),
                             "/dev/null");
507 508 509
        goto cleanup;
    }

510 511 512
    if (outfd != NULL) {
        if (*outfd == -1) {
            if (pipe(pipeout) < 0) {
513
                virReportSystemError(errno,
514
                                     "%s", _("cannot create pipe"));
515 516 517
                goto cleanup;
            }

518
            if ((flags & VIR_EXEC_NONBLOCK) &&
519
                virSetNonBlock(pipeout[0]) == -1) {
520
                virReportSystemError(errno,
521
                                     "%s", _("Failed to set non-blocking file descriptor flag"));
522 523 524 525
                goto cleanup;
            }

            if (virSetCloseExec(pipeout[0]) == -1) {
526
                virReportSystemError(errno,
527
                                     "%s", _("Failed to set close-on-exec file descriptor flag"));
528 529 530 531 532 533
                goto cleanup;
            }

            childout = pipeout[1];
        } else {
            childout = *outfd;
534
        }
535 536
    } else {
        childout = null;
537
    }
538 539 540 541

    if (errfd != NULL) {
        if (*errfd == -1) {
            if (pipe(pipeerr) < 0) {
542
                virReportSystemError(errno,
543
                                     "%s", _("Failed to create pipe"));
544 545 546
                goto cleanup;
            }

547
            if ((flags & VIR_EXEC_NONBLOCK) &&
548
                virSetNonBlock(pipeerr[0]) == -1) {
549
                virReportSystemError(errno,
550
                                     "%s", _("Failed to set non-blocking file descriptor flag"));
551 552 553 554
                goto cleanup;
            }

            if (virSetCloseExec(pipeerr[0]) == -1) {
555
                virReportSystemError(errno,
556
                                     "%s", _("Failed to set close-on-exec file descriptor flag"));
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                goto cleanup;
            }

            childerr = pipeerr[1];
        } else {
            childerr = *errfd;
563
        }
564 565
    } else {
        childerr = null;
566 567
    }

568
    forkRet = virFork(&pid);
569 570

    if (pid < 0) {
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        goto cleanup;
    }

    if (pid) { /* parent */
575
        VIR_FORCE_CLOSE(null);
576
        if (outfd && *outfd == -1) {
577
            VIR_FORCE_CLOSE(pipeout[1]);
578 579
            *outfd = pipeout[0];
        }
580
        if (errfd && *errfd == -1) {
581
            VIR_FORCE_CLOSE(pipeerr[1]);
582 583
            *errfd = pipeerr[0];
        }
584

585 586
        if (forkRet < 0) {
            goto cleanup;
587 588
        }

589
        *retpid = pid;
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        if (binary != argv[0])
            VIR_FREE(binary);

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        return 0;
    }

    /* child */

599 600 601 602
    if (forkRet < 0) {
        /* The fork was sucessful, but after that there was an error
         * in the child (which was already logged).
        */
603
        goto fork_error;
604 605
    }

606
    openmax = sysconf(_SC_OPEN_MAX);
607 608 609 610
    for (i = 3; i < openmax; i++)
        if (i != infd &&
            i != null &&
            i != childout &&
611
            i != childerr &&
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            (!keepfd || i >= FD_SETSIZE || !FD_ISSET(i, keepfd))) {
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            tmpfd = i;
            VIR_FORCE_CLOSE(tmpfd);
        }
616

617
    if (dup2(infd >= 0 ? infd : null, STDIN_FILENO) < 0) {
618
        virReportSystemError(errno,
619
                             "%s", _("failed to setup stdin file handle"));
620
        goto fork_error;
621
    }
622 623
    if (childout > 0 &&
        dup2(childout, STDOUT_FILENO) < 0) {
624
        virReportSystemError(errno,
625
                             "%s", _("failed to setup stdout file handle"));
626
        goto fork_error;
627
    }
628 629
    if (childerr > 0 &&
        dup2(childerr, STDERR_FILENO) < 0) {
630
        virReportSystemError(errno,
631
                             "%s", _("failed to setup stderr file handle"));
632
        goto fork_error;
633
    }
634

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    if (infd != STDIN_FILENO)
        VIR_FORCE_CLOSE(infd);
637
    VIR_FORCE_CLOSE(null);
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    if (childout > STDERR_FILENO) {
        tmpfd = childout;   /* preserve childout value */
        VIR_FORCE_CLOSE(tmpfd);
    }
    if (childerr > STDERR_FILENO &&
643 644 645
        childerr != childout) {
        VIR_FORCE_CLOSE(childerr);
    }
646

647 648 649
    /* Initialize full logging for a while */
    virLogSetFromEnv();

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    /* Daemonize as late as possible, so the parent process can detect
     * the above errors with wait* */
    if (flags & VIR_EXEC_DAEMON) {
        if (setsid() < 0) {
654
            virReportSystemError(errno,
655
                                 "%s", _("cannot become session leader"));
656
            goto fork_error;
657 658 659
        }

        if (chdir("/") < 0) {
660
            virReportSystemError(errno,
661
                                 "%s", _("cannot change to root directory"));
662
            goto fork_error;
663 664 665 666
        }

        pid = fork();
        if (pid < 0) {
667
            virReportSystemError(errno,
668
                                 "%s", _("cannot fork child process"));
669
            goto fork_error;
670 671
        }

672 673
        if (pid > 0) {
            if (pidfile && virFileWritePidPath(pidfile,pid)) {
674 675 676
                kill(pid, SIGTERM);
                usleep(500*1000);
                kill(pid, SIGTERM);
677
                virReportSystemError(errno,
678 679
                                     _("could not write pidfile %s for %d"),
                                     pidfile, pid);
680
                goto fork_error;
681
            }
682
            _exit(0);
683
        }
684 685
    }

686 687 688 689 690 691 692 693 694
    if (hook) {
        /* virFork reset all signal handlers to the defaults.
         * This is good for the child process, but our hook
         * risks running something that generates SIGPIPE,
         * so we need to temporarily block that again
         */
        struct sigaction waxon, waxoff;
        waxoff.sa_handler = SIG_IGN;
        waxoff.sa_flags = 0;
695
        sigemptyset(&waxoff.sa_mask);
696 697 698 699 700 701 702
        memset(&waxon, 0, sizeof(waxon));
        if (sigaction(SIGPIPE, &waxoff, &waxon) < 0) {
            virReportSystemError(errno, "%s",
                                 _("Could not disable SIGPIPE"));
            goto fork_error;
        }

703
        if ((hook)(data) != 0) {
704
            VIR_DEBUG("Hook function failed.");
705
            goto fork_error;
706
        }
707

708 709 710 711 712 713 714
        if (sigaction(SIGPIPE, &waxon, NULL) < 0) {
            virReportSystemError(errno, "%s",
                                 _("Could not re-enable SIGPIPE"));
            goto fork_error;
        }
    }

715 716 717 718
    /* The steps above may need todo something privileged, so
     * we delay clearing capabilities until the last minute */
    if ((flags & VIR_EXEC_CLEAR_CAPS) &&
        virClearCapabilities() < 0)
719
        goto fork_error;
720

721 722 723
    /* Close logging again to ensure no FDs leak to child */
    virLogReset();

724
    if (envp)
725
        execve(binary, (char **) argv, (char**)envp);
726
    else
727
        execv(binary, (char **) argv);
728

729
    virReportSystemError(errno,
730 731
                         _("cannot execute binary %s"),
                         argv[0]);
732

733 734 735
 fork_error:
    virDispatchError(NULL);
    _exit(EXIT_FAILURE);
736 737

 cleanup:
738 739 740
    /* This is cleanup of parent process only - child
       should never jump here on error */

741 742 743
    if (binary != argv[0])
        VIR_FREE(binary);

744
    /* NB we don't virUtilError() on any failures here
745 746
       because the code which jumped hre already raised
       an error condition which we must not overwrite */
747 748 749 750 751
    VIR_FORCE_CLOSE(pipeerr[0]);
    VIR_FORCE_CLOSE(pipeerr[1]);
    VIR_FORCE_CLOSE(pipeout[0]);
    VIR_FORCE_CLOSE(pipeout[1]);
    VIR_FORCE_CLOSE(null);
752 753 754
    return -1;
}

755
/*
756
 * See virExecWithHook for explanation of the arguments.
757
 *
758 759 760
 * Wrapper function for virExecWithHook, with a simpler set of parameters.
 * Used to insulate the numerous callers from changes to virExecWithHook
 * argument list.
761
 */
762
int
763
virExec(const char *const*argv,
764 765 766 767 768 769
        const char *const*envp,
        const fd_set *keepfd,
        pid_t *retpid,
        int infd, int *outfd, int *errfd,
        int flags)
{
770
    return virExecWithHook(argv, envp, keepfd, retpid,
771
                           infd, outfd, errfd,
772
                           flags, NULL, NULL, NULL);
773 774
}

775 776 777 778 779 780 781 782 783 784 785 786 787 788 789
/**
 * @argv NULL terminated argv to run
 * @status optional variable to return exit status in
 *
 * Run a command without using the shell.
 *
 * If status is NULL, then return 0 if the command run and
 * exited with 0 status; Otherwise return -1
 *
 * If status is not-NULL, then return 0 if the command ran.
 * The status variable is filled with the command exit status
 * and should be checked by caller for success. Return -1
 * only if the command could not be run.
 */
int
790 791
virRun(const char *const*argv, int *status)
{
792 793
    pid_t childpid;
    int exitstatus, execret, waitret;
C
Cole Robinson 已提交
794 795 796 797 798
    int ret = -1;
    int errfd = -1, outfd = -1;
    char *outbuf = NULL;
    char *errbuf = NULL;
    char *argv_str = NULL;
799 800

    if ((argv_str = virArgvToString(argv)) == NULL) {
801
        virReportOOMError();
C
Cole Robinson 已提交
802
        goto error;
803
    }
804
    VIR_DEBUG("%s", argv_str);
805

806 807
    if ((execret = virExecWithHook(argv, NULL, NULL,
                                   &childpid, -1, &outfd, &errfd,
808
                                   VIR_EXEC_NONE, NULL, NULL, NULL)) < 0) {
C
Cole Robinson 已提交
809 810 811 812
        ret = execret;
        goto error;
    }

813
    if (virPipeReadUntilEOF(outfd, errfd, &outbuf, &errbuf) < 0) {
814 815
        while (waitpid(childpid, &exitstatus, 0) == -1 && errno == EINTR)
            ;
C
Cole Robinson 已提交
816
        goto error;
817
    }
C
Cole Robinson 已提交
818 819

    if (outbuf)
820
        VIR_DEBUG("Command stdout: %s", outbuf);
C
Cole Robinson 已提交
821
    if (errbuf)
822
        VIR_DEBUG("Command stderr: %s", errbuf);
823

C
Cole Robinson 已提交
824 825 826
    while ((waitret = waitpid(childpid, &exitstatus, 0) == -1) &&
            errno == EINTR);
    if (waitret == -1) {
827
        virReportSystemError(errno,
828 829
                             _("cannot wait for '%s'"),
                             argv[0]);
C
Cole Robinson 已提交
830
        goto error;
831
    }
832 833 834

    if (status == NULL) {
        errno = EINVAL;
835 836
        if (exitstatus) {
            char *str = virCommandTranslateStatus(exitstatus);
837 838 839 840 841 842
            char *argvstr = virArgvToString(argv);
            if (!argv_str) {
                virReportOOMError();
                goto error;
            }

843
            virUtilError(VIR_ERR_INTERNAL_ERROR,
844 845
                         _("'%s' exited unexpectedly: %s"),
                         argv_str, NULLSTR(str));
846

847
            VIR_FREE(str);
848
            VIR_FREE(argvstr);
C
Cole Robinson 已提交
849 850
            goto error;
        }
851 852 853
    } else {
        *status = exitstatus;
    }
C
Cole Robinson 已提交
854 855 856 857 858 859

    ret = 0;

  error:
    VIR_FREE(outbuf);
    VIR_FREE(errbuf);
860 861
    VIR_FORCE_CLOSE(outfd);
    VIR_FORCE_CLOSE(errfd);
C
Cole Robinson 已提交
862
    return ret;
863 864
}

865
#else /* WIN32 */
866

E
Eric Blake 已提交
867
int virSetInherit(int fd ATTRIBUTE_UNUSED, bool inherit ATTRIBUTE_UNUSED)
868 869 870
{
    return -1;
}
871

872
int
873 874
virRun(const char *const *argv ATTRIBUTE_UNUSED,
       int *status)
J
Jim Meyering 已提交
875 876 877 878
{
    if (status)
        *status = ENOTSUP;
    else
879
        virUtilError(VIR_ERR_INTERNAL_ERROR,
880
                     "%s", _("virRun is not implemented for WIN32"));
J
Jim Meyering 已提交
881 882 883
    return -1;
}

884
int
885
virExec(const char *const*argv ATTRIBUTE_UNUSED,
D
Daniel P. Berrange 已提交
886 887
        const char *const*envp ATTRIBUTE_UNUSED,
        const fd_set *keepfd ATTRIBUTE_UNUSED,
888 889 890
        int *retpid ATTRIBUTE_UNUSED,
        int infd ATTRIBUTE_UNUSED,
        int *outfd ATTRIBUTE_UNUSED,
D
Daniel P. Berrange 已提交
891 892
        int *errfd ATTRIBUTE_UNUSED,
        int flags ATTRIBUTE_UNUSED)
893
{
894 895 896 897 898
    virUtilError(VIR_ERR_INTERNAL_ERROR,
                 "%s", _("virExec is not implemented for WIN32"));
    return -1;
}

899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920
int
virExecWithHook(const char *const*argv ATTRIBUTE_UNUSED,
                const char *const*envp ATTRIBUTE_UNUSED,
                const fd_set *keepfd ATTRIBUTE_UNUSED,
                pid_t *retpid ATTRIBUTE_UNUSED,
                int infd ATTRIBUTE_UNUSED,
                int *outfd ATTRIBUTE_UNUSED,
                int *errfd ATTRIBUTE_UNUSED,
                int flags ATTRIBUTE_UNUSED,
                virExecHook hook ATTRIBUTE_UNUSED,
                void *data ATTRIBUTE_UNUSED,
                char *pidfile ATTRIBUTE_UNUSED)
{
    /* XXX: Some day we can implement pieces of virCommand/virExec on
     * top of _spawn() or CreateProcess(), but we can't implement
     * everything, since mingw completely lacks fork(), so we cannot
     * run hook code in the child.  */
    virUtilError(VIR_ERR_INTERNAL_ERROR,
                 "%s", _("virExec is not implemented for WIN32"));
    return -1;
}

921 922 923 924 925 926 927 928 929
int
virFork(pid_t *pid)
{
    *pid = -1;
    errno = ENOTSUP;

    return -1;
}

930
#endif /* WIN32 */
931

932 933 934 935 936 937 938 939 940 941
int
virPipeReadUntilEOF(int outfd, int errfd,
                    char **outbuf, char **errbuf) {

    struct pollfd fds[2];
    int i;
    int finished[2];

    fds[0].fd = outfd;
    fds[0].events = POLLIN;
942
    fds[0].revents = 0;
943 944 945
    finished[0] = 0;
    fds[1].fd = errfd;
    fds[1].events = POLLIN;
946
    fds[1].revents = 0;
947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976
    finished[1] = 0;

    while(!(finished[0] && finished[1])) {

        if (poll(fds, ARRAY_CARDINALITY(fds), -1) < 0) {
            if ((errno == EAGAIN) || (errno == EINTR))
                continue;
            goto pollerr;
        }

        for (i = 0; i < ARRAY_CARDINALITY(fds); ++i) {
            char data[1024], **buf;
            int got, size;

            if (!(fds[i].revents))
                continue;
            else if (fds[i].revents & POLLHUP)
                finished[i] = 1;

            if (!(fds[i].revents & POLLIN)) {
                if (fds[i].revents & POLLHUP)
                    continue;

                virUtilError(VIR_ERR_INTERNAL_ERROR,
                             "%s", _("Unknown poll response."));
                goto error;
            }

            got = read(fds[i].fd, data, sizeof(data));

977 978 979
            if (got == sizeof(data))
                finished[i] = 0;

980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016
            if (got == 0) {
                finished[i] = 1;
                continue;
            }
            if (got < 0) {
                if (errno == EINTR)
                    continue;
                if (errno == EAGAIN)
                    break;
                goto pollerr;
            }

            buf = ((fds[i].fd == outfd) ? outbuf : errbuf);
            size = (*buf ? strlen(*buf) : 0);
            if (VIR_REALLOC_N(*buf, size+got+1) < 0) {
                virReportOOMError();
                goto error;
            }
            memmove(*buf+size, data, got);
            (*buf)[size+got] = '\0';
        }
        continue;

    pollerr:
        virReportSystemError(errno,
                             "%s", _("poll error"));
        goto error;
    }

    return 0;

error:
    VIR_FREE(*outbuf);
    VIR_FREE(*errbuf);
    return -1;
}

1017 1018 1019 1020
/* Like gnulib's fread_file, but read no more than the specified maximum
   number of bytes.  If the length of the input is <= max_len, and
   upon error while reading that data, it works just like fread_file.  */
static char *
1021
saferead_lim (int fd, size_t max_len, size_t *length)
1022 1023 1024 1025 1026 1027 1028
{
    char *buf = NULL;
    size_t alloc = 0;
    size_t size = 0;
    int save_errno;

    for (;;) {
1029 1030
        int count;
        int requested;
1031 1032 1033 1034 1035 1036

        if (size + BUFSIZ + 1 > alloc) {
            alloc += alloc / 2;
            if (alloc < size + BUFSIZ + 1)
                alloc = size + BUFSIZ + 1;

1037
            if (VIR_REALLOC_N(buf, alloc) < 0) {
1038 1039 1040 1041 1042 1043 1044 1045
                save_errno = errno;
                break;
            }
        }

        /* Ensure that (size + requested <= max_len); */
        requested = MIN (size < max_len ? max_len - size : 0,
                         alloc - size - 1);
1046
        count = saferead (fd, buf + size, requested);
1047 1048 1049 1050
        size += count;

        if (count != requested || requested == 0) {
            save_errno = errno;
1051
            if (count < 0)
1052 1053 1054 1055 1056 1057 1058
                break;
            buf[size] = '\0';
            *length = size;
            return buf;
        }
    }

1059
    VIR_FREE(buf);
1060 1061 1062
    errno = save_errno;
    return NULL;
}
1063

1064
/* A wrapper around saferead_lim that maps a failure due to
1065
   exceeding the maximum size limitation to EOVERFLOW.  */
1066 1067
int
virFileReadLimFD(int fd, int maxlen, char **buf)
1068
{
1069
    size_t len;
1070 1071 1072 1073 1074 1075 1076
    char *s;

    if (maxlen <= 0) {
        errno = EINVAL;
        return -1;
    }
    s = saferead_lim (fd, maxlen+1, &len);
1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089
    if (s == NULL)
        return -1;
    if (len > maxlen || (int)len != len) {
        VIR_FREE(s);
        /* There was at least one byte more than MAXLEN.
           Set errno accordingly. */
        errno = EOVERFLOW;
        return -1;
    }
    *buf = s;
    return len;
}

D
Daniel P. Berrange 已提交
1090
int virFileReadAll(const char *path, int maxlen, char **buf)
1091
{
1092 1093
    int fd = open(path, O_RDONLY);
    if (fd < 0) {
1094
        virReportSystemError(errno, _("Failed to open file '%s'"), path);
1095
        return -1;
1096 1097
    }

1098
    int len = virFileReadLimFD(fd, maxlen, buf);
1099
    VIR_FORCE_CLOSE(fd);
1100
    if (len < 0) {
1101
        virReportSystemError(errno, _("Failed to read file '%s'"), path);
1102
        return -1;
1103 1104
    }

1105
    return len;
1106 1107
}

1108 1109
/* Truncate @path and write @str to it.  If @mode is 0, ensure that
   @path exists; otherwise, use @mode if @path must be created.
M
Mark McLoughlin 已提交
1110 1111
   Return 0 for success, nonzero for failure.
   Be careful to preserve any errno value upon failure. */
1112
int virFileWriteStr(const char *path, const char *str, mode_t mode)
M
Mark McLoughlin 已提交
1113 1114 1115
{
    int fd;

1116 1117 1118 1119 1120
    if (mode)
        fd = open(path, O_WRONLY|O_TRUNC|O_CREAT, mode);
    else
        fd = open(path, O_WRONLY|O_TRUNC);
    if (fd == -1)
M
Mark McLoughlin 已提交
1121 1122 1123
        return -1;

    if (safewrite(fd, str, strlen(str)) < 0) {
1124
        VIR_FORCE_CLOSE(fd);
M
Mark McLoughlin 已提交
1125 1126 1127 1128
        return -1;
    }

    /* Use errno from failed close only if there was no write error.  */
1129
    if (VIR_CLOSE(fd) != 0)
M
Mark McLoughlin 已提交
1130 1131 1132 1133 1134
        return -1;

    return 0;
}

1135 1136 1137 1138 1139 1140 1141 1142 1143
int virFileMatchesNameSuffix(const char *file,
                             const char *name,
                             const char *suffix)
{
    int filelen = strlen(file);
    int namelen = strlen(name);
    int suffixlen = strlen(suffix);

    if (filelen == (namelen + suffixlen) &&
1144 1145
        STREQLEN(file, name, namelen) &&
        STREQLEN(file + namelen, suffix, suffixlen))
1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159
        return 1;
    else
        return 0;
}

int virFileHasSuffix(const char *str,
                     const char *suffix)
{
    int len = strlen(str);
    int suffixlen = strlen(suffix);

    if (len < suffixlen)
        return 0;

1160
    return STRCASEEQ(str + len - suffixlen, suffix);
1161 1162
}

1163
#define SAME_INODE(Stat_buf_1, Stat_buf_2) \
J
Jim Meyering 已提交
1164 1165
  ((Stat_buf_1).st_ino == (Stat_buf_2).st_ino \
   && (Stat_buf_1).st_dev == (Stat_buf_2).st_dev)
1166

J
Jim Meyering 已提交
1167 1168
/* Return nonzero if checkLink and checkDest
   refer to the same file.  Otherwise, return 0.  */
1169 1170 1171
int virFileLinkPointsTo(const char *checkLink,
                        const char *checkDest)
{
J
Jim Meyering 已提交
1172 1173
    struct stat src_sb;
    struct stat dest_sb;
1174

J
Jim Meyering 已提交
1175 1176 1177
    return (stat (checkLink, &src_sb) == 0
            && stat (checkDest, &dest_sb) == 0
            && SAME_INODE (src_sb, dest_sb));
1178 1179
}

D
Daniel P. Berrange 已提交
1180 1181 1182


/*
1183 1184 1185
 * Attempt to resolve a symbolic link, returning an
 * absolute path where only the last component is guaranteed
 * not to be a symlink.
D
Daniel P. Berrange 已提交
1186 1187
 *
 * Return 0 if path was not a symbolic, or the link was
1188
 * resolved. Return -1 with errno set upon error
D
Daniel P. Berrange 已提交
1189 1190 1191 1192 1193 1194 1195 1196
 */
int virFileResolveLink(const char *linkpath,
                       char **resultpath)
{
    struct stat st;

    *resultpath = NULL;

1197 1198 1199 1200 1201
    /* We don't need the full canonicalization of intermediate
     * directories, if linkpath is absolute and the basename is
     * already a non-symlink.  */
    if (IS_ABSOLUTE_FILE_NAME(linkpath)) {
        if (lstat(linkpath, &st) < 0)
1202
            return -1;
1203 1204 1205 1206 1207 1208

        if (!S_ISLNK(st.st_mode)) {
            if (!(*resultpath = strdup(linkpath)))
                return -1;
            return 0;
        }
D
Daniel P. Berrange 已提交
1209 1210
    }

1211
    *resultpath = canonicalize_file_name(linkpath);
D
Daniel P. Berrange 已提交
1212

1213
    return *resultpath == NULL ? -1 : 0;
D
Daniel P. Berrange 已提交
1214 1215
}

1216
/*
1217
 * Finds a requested executable file in the PATH env. e.g.:
1218 1219 1220 1221 1222 1223
 * "kvm-img" will return "/usr/bin/kvm-img"
 *
 * You must free the result
 */
char *virFindFileInPath(const char *file)
{
1224
    char *path;
1225
    char *pathiter;
1226
    char *pathseg;
1227
    char *fullpath = NULL;
1228

1229 1230 1231 1232
    if (file == NULL)
        return NULL;

    /* if we are passed an absolute path (starting with /), return a
1233
     * copy of that path, after validating that it is executable
1234
     */
1235 1236
    if (IS_ABSOLUTE_FILE_NAME(file)) {
        if (virFileIsExecutable(file))
1237 1238 1239 1240 1241
            return strdup(file);
        else
            return NULL;
    }

1242
    /* copy PATH env so we can tweak it */
1243 1244
    path = getenv("PATH");

1245
    if (path == NULL || (path = strdup(path)) == NULL)
C
Chris Lalancette 已提交
1246
        return NULL;
D
Daniel P. Berrange 已提交
1247

1248 1249 1250
    /* for each path segment, append the file to search for and test for
     * it. return it if found.
     */
1251 1252 1253 1254 1255 1256
    pathiter = path;
    while ((pathseg = strsep(&pathiter, ":")) != NULL) {
        if (virAsprintf(&fullpath, "%s/%s", pathseg, file) < 0 ||
            virFileIsExecutable(fullpath))
            break;
        VIR_FREE(fullpath);
1257 1258
    }

1259 1260
    VIR_FREE(path);
    return fullpath;
1261
}
1262 1263

bool virFileExists(const char *path)
1264
{
1265 1266 1267
    return access(path, F_OK) == 0;
}

1268 1269
/* Check that a file is regular and has executable bits.  If false is
 * returned, errno is valid.
1270 1271 1272 1273 1274 1275 1276 1277 1278
 *
 * Note: In the presence of ACLs, this may return true for a file that
 * would actually fail with EACCES for a given user, or false for a
 * file that the user could actually execute, but setups with ACLs
 * that weird are unusual. */
bool
virFileIsExecutable(const char *file)
{
    struct stat sb;
1279

1280 1281
    /* We would also want to check faccessat if we cared about ACLs,
     * but we don't.  */
1282 1283 1284 1285 1286 1287
    if (stat(file, &sb) < 0)
        return false;
    if (S_ISREG(sb.st_mode) && (sb.st_mode & 0111) != 0)
        return true;
    errno = S_ISDIR(sb.st_mode) ? EISDIR : EACCES;
    return false;
1288 1289
}

1290
#ifndef WIN32
1291
/* return -errno on failure, or 0 on success */
1292 1293 1294 1295
static int
virFileOpenAsNoFork(const char *path, int openflags, mode_t mode,
                    uid_t uid, gid_t gid, unsigned int flags)
{
1296 1297 1298 1299
    int fd = -1;
    int ret = 0;
    struct stat st;

1300
    if ((fd = open(path, openflags, mode)) < 0) {
1301
        ret = -errno;
1302
        virReportSystemError(errno, _("failed to create file '%s'"),
1303 1304 1305 1306
                             path);
        goto error;
    }
    if (fstat(fd, &st) == -1) {
1307
        ret = -errno;
1308
        virReportSystemError(errno, _("stat of '%s' failed"), path);
1309 1310 1311 1312
        goto error;
    }
    if (((st.st_uid != uid) || (st.st_gid != gid))
        && (fchown(fd, uid, gid) < 0)) {
1313
        ret = -errno;
1314
        virReportSystemError(errno, _("cannot chown '%s' to (%u, %u)"),
E
Eric Blake 已提交
1315
                             path, (unsigned int) uid, (unsigned int) gid);
1316 1317
        goto error;
    }
1318
    if ((flags & VIR_FILE_OPEN_FORCE_PERMS)
1319
        && (fchmod(fd, mode) < 0)) {
1320
        ret = -errno;
1321
        virReportSystemError(errno,
1322 1323 1324 1325
                             _("cannot set mode of '%s' to %04o"),
                             path, mode);
        goto error;
    }
1326
    return fd;
1327

1328
error:
1329
    VIR_FORCE_CLOSE(fd);
1330 1331 1332
    return ret;
}

1333
/* return -errno on failure, or 0 on success */
1334
static int virDirCreateNoFork(const char *path, mode_t mode, uid_t uid, gid_t gid,
1335 1336 1337 1338 1339
                              unsigned int flags) {
    int ret = 0;
    struct stat st;

    if ((mkdir(path, mode) < 0)
1340
        && !((errno == EEXIST) && (flags & VIR_DIR_CREATE_ALLOW_EXIST))) {
1341
        ret = -errno;
1342
        virReportSystemError(errno, _("failed to create directory '%s'"),
1343 1344 1345 1346 1347
                             path);
        goto error;
    }

    if (stat(path, &st) == -1) {
1348
        ret = -errno;
1349
        virReportSystemError(errno, _("stat of '%s' failed"), path);
1350 1351 1352 1353
        goto error;
    }
    if (((st.st_uid != uid) || (st.st_gid != gid))
        && (chown(path, uid, gid) < 0)) {
1354
        ret = -errno;
1355
        virReportSystemError(errno, _("cannot chown '%s' to (%u, %u)"),
E
Eric Blake 已提交
1356
                             path, (unsigned int) uid, (unsigned int) gid);
1357 1358
        goto error;
    }
1359 1360
    if ((flags & VIR_DIR_CREATE_FORCE_PERMS)
        && (chmod(path, mode) < 0)) {
1361
        ret = -errno;
1362
        virReportSystemError(errno,
1363 1364 1365 1366 1367 1368 1369 1370
                             _("cannot set mode of '%s' to %04o"),
                             path, mode);
        goto error;
    }
error:
    return ret;
}

1371
/**
1372
 * virFileOpenAs:
1373 1374 1375 1376 1377
 * @path: file to open or create
 * @openflags: flags to pass to open
 * @mode: mode to use on creation or when forcing permissions
 * @uid: uid that should own file on creation
 * @gid: gid that should own file
1378
 * @flags: bit-wise or of VIR_FILE_OPEN_* flags
1379 1380 1381
 *
 * Open @path, and execute an optional callback @hook on the open file
 * description.  @hook must return 0 on success, or -errno on failure.
1382
 * If @flags includes VIR_FILE_OPEN_AS_UID, then open the file while the
1383 1384
 * effective user id is @uid (by using a child process); this allows
 * one to bypass root-squashing NFS issues.  If @flags includes
1385
 * VIR_FILE_OPEN_FORCE_PERMS, then ensure that @path has those
1386
 * permissions before the callback, even if the file already existed
1387 1388 1389 1390 1391 1392
 * with different permissions.  The return value (if non-negative)
 * is the file descriptor, left open.  Return -errno on failure.  */
int
virFileOpenAs(const char *path, int openflags, mode_t mode,
              uid_t uid, gid_t gid, unsigned int flags)
{
1393 1394 1395
    struct stat st;
    pid_t pid;
    int waitret, status, ret = 0;
1396 1397 1398
    int fd = -1;
    int pair[2] = { -1, -1 };
    int forkRet;
1399

1400
    if ((!(flags & VIR_FILE_OPEN_AS_UID))
1401
        || (getuid() != 0)
1402
        || ((uid == 0) && (gid == 0))) {
1403
        return virFileOpenAsNoFork(path, openflags, mode, uid, gid, flags);
1404 1405 1406 1407 1408 1409 1410
    }

    /* parent is running as root, but caller requested that the
     * file be created as some other user and/or group). The
     * following dance avoids problems caused by root-squashing
     * NFS servers. */

1411 1412 1413 1414 1415 1416
    if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) < 0) {
        ret = -errno;
        virReportSystemError(errno,
                             _("failed to create socket needed for '%s'"),
                             path);
        return ret;
1417 1418 1419
    }

    forkRet = virFork(&pid);
1420 1421

    if (pid < 0) {
1422
        ret = -errno;
1423 1424 1425 1426
        return ret;
    }

    if (pid) { /* parent */
1427 1428 1429
        VIR_FORCE_CLOSE(pair[1]);

        do {
1430
            ret = recvfd(pair[0], 0);
1431 1432
        } while (ret < 0 && errno == EINTR);

1433
        if (ret < 0 && errno != EACCES) {
1434
            ret = -errno;
1435
            VIR_FORCE_CLOSE(pair[0]);
E
Eric Blake 已提交
1436
            while (waitpid(pid, NULL, 0) == -1 && errno == EINTR);
1437
            goto parenterror;
1438 1439
        } else {
            fd = ret;
1440 1441
        }
        VIR_FORCE_CLOSE(pair[0]);
1442

1443 1444 1445 1446
        /* wait for child to complete, and retrieve its exit code */
        while ((waitret = waitpid(pid, &status, 0) == -1)
               && (errno == EINTR));
        if (waitret == -1) {
1447
            ret = -errno;
1448
            virReportSystemError(errno,
1449 1450
                                 _("failed to wait for child creating '%s'"),
                                 path);
1451
            VIR_FORCE_CLOSE(fd);
1452 1453
            goto parenterror;
        }
1454
        if (!WIFEXITED(status) || (ret = -WEXITSTATUS(status)) == -EACCES ||
1455
            fd == -1) {
1456 1457
            /* fall back to the simpler method, which works better in
             * some cases */
1458
            VIR_FORCE_CLOSE(fd);
1459
            return virFileOpenAsNoFork(path, openflags, mode, uid, gid, flags);
1460
        }
1461
        if (!ret)
1462
            ret = fd;
1463 1464 1465 1466
parenterror:
        return ret;
    }

1467 1468 1469 1470 1471

    /* child */

    if (forkRet < 0) {
        /* error encountered and logged in virFork() after the fork. */
1472
        ret = -errno;
1473 1474
        goto childerror;
    }
1475
    VIR_FORCE_CLOSE(pair[0]);
1476 1477

    /* set desired uid/gid, then attempt to create the file */
1478

1479
    if (virSetUIDGID(uid, gid) < 0) {
1480
        ret = -errno;
1481 1482
        goto childerror;
    }
1483
    if ((fd = open(path, openflags, mode)) < 0) {
1484 1485
        ret = -errno;
        if (ret != -EACCES) {
1486
            /* in case of EACCES, the parent will retry */
1487
            virReportSystemError(errno,
1488 1489 1490 1491 1492
                                 _("child failed to create file '%s'"),
                                 path);
        }
        goto childerror;
    }
1493
    if (fstat(fd, &st) == -1) {
1494
        ret = -errno;
1495 1496 1497 1498 1499
        virReportSystemError(errno, _("stat of '%s' failed"), path);
        goto childerror;
    }
    if ((st.st_gid != gid)
        && (fchown(fd, -1, gid) < 0)) {
1500
        ret = -errno;
1501
        virReportSystemError(errno, _("cannot chown '%s' to (%u, %u)"),
E
Eric Blake 已提交
1502
                             path, (unsigned int) uid, (unsigned int) gid);
1503 1504
        goto childerror;
    }
1505
    if ((flags & VIR_FILE_OPEN_FORCE_PERMS)
1506
        && (fchmod(fd, mode) < 0)) {
1507
        ret = -errno;
1508 1509 1510 1511 1512
        virReportSystemError(errno,
                             _("cannot set mode of '%s' to %04o"),
                             path, mode);
        goto childerror;
    }
1513

1514
    do {
1515
        ret = sendfd(pair[1], fd);
1516
    } while (ret < 0 && errno == EINTR);
1517

1518 1519 1520
    if (ret < 0) {
        ret = -errno;
        goto childerror;
1521
    }
1522

1523
childerror:
1524 1525 1526 1527
    /* ret tracks -errno on failure, but exit value must be positive.
     * If the child exits with EACCES, then the parent tries again.  */
    /* XXX This makes assumptions about errno being < 255, which is
     * not true on Hurd.  */
1528
    VIR_FORCE_CLOSE(pair[1]);
1529 1530 1531 1532 1533
    ret = -ret;
    if ((ret & 0xff) != ret) {
        VIR_WARN("unable to pass desired return value %d", ret);
        ret = 0xff;
    }
1534 1535 1536 1537
    _exit(ret);

}

1538
/* return -errno on failure, or 0 on success */
1539 1540 1541 1542 1543 1544 1545
int virDirCreate(const char *path, mode_t mode,
                 uid_t uid, gid_t gid, unsigned int flags) {
    struct stat st;
    pid_t pid;
    int waitret;
    int status, ret = 0;

1546
    if ((!(flags & VIR_DIR_CREATE_AS_UID))
1547 1548
        || (getuid() != 0)
        || ((uid == 0) && (gid == 0))
1549 1550
        || ((flags & VIR_DIR_CREATE_ALLOW_EXIST) && (stat(path, &st) >= 0))) {
        return virDirCreateNoFork(path, mode, uid, gid, flags);
1551 1552
    }

1553
    int forkRet = virFork(&pid);
1554 1555

    if (pid < 0) {
1556
        ret = -errno;
1557 1558 1559 1560 1561 1562 1563
        return ret;
    }

    if (pid) { /* parent */
        /* wait for child to complete, and retrieve its exit code */
        while ((waitret = waitpid(pid, &status, 0) == -1)  && (errno == EINTR));
        if (waitret == -1) {
1564
            ret = -errno;
1565
            virReportSystemError(errno,
1566 1567 1568 1569
                                 _("failed to wait for child creating '%s'"),
                                 path);
            goto parenterror;
        }
1570
        if (!WIFEXITED(status) || (ret = -WEXITSTATUS(status)) == -EACCES) {
1571 1572
            /* fall back to the simpler method, which works better in
             * some cases */
1573
            return virDirCreateNoFork(path, mode, uid, gid, flags);
1574 1575 1576 1577 1578
        }
parenterror:
        return ret;
    }

1579 1580 1581 1582 1583 1584 1585 1586
    /* child */

    if (forkRet < 0) {
        /* error encountered and logged in virFork() after the fork. */
        goto childerror;
    }

    /* set desired uid/gid, then attempt to create the directory */
1587

1588
    if (virSetUIDGID(uid, gid) < 0) {
1589
        ret = -errno;
1590 1591 1592
        goto childerror;
    }
    if (mkdir(path, mode) < 0) {
1593 1594
        ret = -errno;
        if (ret != -EACCES) {
1595
            /* in case of EACCES, the parent will retry */
1596
            virReportSystemError(errno, _("child failed to create directory '%s'"),
1597 1598 1599 1600
                                 path);
        }
        goto childerror;
    }
1601 1602 1603
    /* check if group was set properly by creating after
     * setgid. If not, try doing it with chown */
    if (stat(path, &st) == -1) {
1604
        ret = -errno;
1605 1606 1607 1608 1609
        virReportSystemError(errno,
                             _("stat of '%s' failed"), path);
        goto childerror;
    }
    if ((st.st_gid != gid) && (chown(path, -1, gid) < 0)) {
1610
        ret = -errno;
1611 1612
        virReportSystemError(errno,
                             _("cannot chown '%s' to group %u"),
E
Eric Blake 已提交
1613
                             path, (unsigned int) gid);
1614 1615 1616 1617 1618 1619 1620 1621 1622
        goto childerror;
    }
    if ((flags & VIR_DIR_CREATE_FORCE_PERMS)
        && chmod(path, mode) < 0) {
        virReportSystemError(errno,
                             _("cannot set mode of '%s' to %04o"),
                             path, mode);
        goto childerror;
    }
1623 1624 1625 1626
childerror:
    _exit(ret);
}

1627
#else /* WIN32 */
1628

1629
/* return -errno on failure, or 0 on success */
1630 1631 1632 1633 1634 1635
int virFileOpenAs(const char *path ATTRIBUTE_UNUSED,
                  int openflags ATTRIBUTE_UNUSED,
                  mode_t mode ATTRIBUTE_UNUSED,
                  uid_t uid ATTRIBUTE_UNUSED,
                  gid_t gid ATTRIBUTE_UNUSED,
                  unsigned int flags ATTRIBUTE_UNUSED)
1636 1637
{
    virUtilError(VIR_ERR_INTERNAL_ERROR,
1638
                 "%s", _("virFileOpenAs is not implemented for WIN32"));
1639

1640
    return -ENOSYS;
1641 1642
}

1643 1644 1645 1646 1647 1648 1649 1650 1651
int virDirCreate(const char *path ATTRIBUTE_UNUSED,
                 mode_t mode ATTRIBUTE_UNUSED,
                 uid_t uid ATTRIBUTE_UNUSED,
                 gid_t gid ATTRIBUTE_UNUSED,
                 unsigned int flags ATTRIBUTE_UNUSED)
{
    virUtilError(VIR_ERR_INTERNAL_ERROR,
                 "%s", _("virDirCreate is not implemented for WIN32"));

1652
    return -ENOSYS;
1653
}
1654
#endif /* WIN32 */
1655

1656
static int virFileMakePathHelper(char *path) {
1657
    struct stat st;
1658
    char *p = NULL;
1659 1660 1661 1662 1663
    int err;

    if (stat(path, &st) >= 0)
        return 0;

1664
    if ((p = strrchr(path, '/')) == NULL)
1665 1666
        return EINVAL;

1667
    if (p != path) {
1668
        *p = '\0';
1669 1670 1671
        err = virFileMakePathHelper(path);
        *p = '/';
        if (err != 0)
1672 1673
            return err;
    }
1674

1675
    if (mkdir(path, 0777) < 0 && errno != EEXIST) {
1676
        return errno;
1677
    }
1678 1679 1680
    return 0;
}

1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717
int virFileMakePath(const char *path)
{
    struct stat st;
    char *parent = NULL;
    char *p;
    int err = 0;

    if (stat(path, &st) >= 0)
        goto cleanup;

    if ((parent = strdup(path)) == NULL) {
        err = ENOMEM;
        goto cleanup;
    }

    if ((p = strrchr(parent, '/')) == NULL) {
        err = EINVAL;
        goto cleanup;
    }

    if (p != parent) {
        *p = '\0';
        if ((err = virFileMakePathHelper(parent)) != 0) {
            goto cleanup;
        }
    }

    if (mkdir(path, 0777) < 0 && errno != EEXIST) {
        err = errno;
        goto cleanup;
    }

cleanup:
    VIR_FREE(parent);
    return err;
}

1718
/* Build up a fully qualified path for a config file to be
1719
 * associated with a persistent guest or network */
1720 1721
char *
virFileBuildPath(const char *dir, const char *name, const char *ext)
1722
{
1723
    char *path;
1724

1725 1726
    if (ext == NULL) {
        if (virAsprintf(&path, "%s/%s", dir, name) < 0) {
1727
            virReportOOMError();
1728 1729 1730 1731
            return NULL;
        }
    } else {
        if (virAsprintf(&path, "%s/%s%s", dir, name, ext) < 0) {
1732
            virReportOOMError();
1733 1734 1735 1736 1737
            return NULL;
        }
    }

    return path;
1738 1739
}

1740 1741 1742 1743

int virFileOpenTty(int *ttymaster,
                   char **ttyName,
                   int rawmode)
1744 1745 1746 1747 1748 1749 1750
{
    return virFileOpenTtyAt("/dev/ptmx",
                            ttymaster,
                            ttyName,
                            rawmode);
}

1751
#ifdef __linux__
1752 1753 1754 1755
int virFileOpenTtyAt(const char *ptmx,
                     int *ttymaster,
                     char **ttyName,
                     int rawmode)
1756 1757 1758
{
    int rc = -1;

1759
    if ((*ttymaster = open(ptmx, O_RDWR|O_NOCTTY|O_NONBLOCK)) < 0)
1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779
        goto cleanup;

    if (unlockpt(*ttymaster) < 0)
        goto cleanup;

    if (grantpt(*ttymaster) < 0)
        goto cleanup;

    if (rawmode) {
        struct termios ttyAttr;
        if (tcgetattr(*ttymaster, &ttyAttr) < 0)
            goto cleanup;

        cfmakeraw(&ttyAttr);

        if (tcsetattr(*ttymaster, TCSADRAIN, &ttyAttr) < 0)
            goto cleanup;
    }

    if (ttyName) {
1780
        if (VIR_ALLOC_N(*ttyName, PATH_MAX) < 0) {
1781 1782 1783
            errno = ENOMEM;
            goto cleanup;
        }
1784 1785 1786

        if (ptsname_r(*ttymaster, *ttyName, PATH_MAX) < 0)
            goto cleanup;
1787 1788 1789 1790 1791
    }

    rc = 0;

cleanup:
1792 1793
    if (rc != 0)
        VIR_FORCE_CLOSE(*ttymaster);
1794 1795 1796 1797

    return rc;

}
1798
#else
1799 1800 1801 1802
int virFileOpenTtyAt(const char *ptmx ATTRIBUTE_UNUSED,
                     int *ttymaster ATTRIBUTE_UNUSED,
                     char **ttyName ATTRIBUTE_UNUSED,
                     int rawmode ATTRIBUTE_UNUSED)
1803 1804 1805
{
    return -1;
}
1806
#endif
1807

1808 1809
char* virFilePid(const char *dir, const char* name)
{
1810
    char *pidfile;
1811 1812
    if (virAsprintf(&pidfile, "%s/%s.pid", dir, name) < 0)
        return NULL;
1813 1814 1815
    return pidfile;
}

1816 1817 1818 1819 1820 1821 1822
int virFileWritePid(const char *dir,
                    const char *name,
                    pid_t pid)
{
    int rc;
    char *pidfile = NULL;

1823 1824 1825 1826 1827
    if (name == NULL || dir == NULL) {
        rc = EINVAL;
        goto cleanup;
    }

1828 1829 1830
    if ((rc = virFileMakePath(dir)))
        goto cleanup;

1831
    if (!(pidfile = virFilePid(dir, name))) {
1832 1833 1834 1835
        rc = ENOMEM;
        goto cleanup;
    }

1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849
    rc = virFileWritePidPath(pidfile, pid);

cleanup:
    VIR_FREE(pidfile);
    return rc;
}

int virFileWritePidPath(const char *pidfile,
                        pid_t pid)
{
    int rc;
    int fd;
    FILE *file = NULL;

1850 1851 1852 1853 1854 1855 1856
    if ((fd = open(pidfile,
                   O_WRONLY | O_CREAT | O_TRUNC,
                   S_IRUSR | S_IWUSR)) < 0) {
        rc = errno;
        goto cleanup;
    }

1857
    if (!(file = VIR_FDOPEN(fd, "w"))) {
1858
        rc = errno;
1859
        VIR_FORCE_CLOSE(fd);
1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870
        goto cleanup;
    }

    if (fprintf(file, "%d", pid) < 0) {
        rc = errno;
        goto cleanup;
    }

    rc = 0;

cleanup:
1871
    if (VIR_FCLOSE(file) < 0)
1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884
        rc = errno;

    return rc;
}

int virFileReadPid(const char *dir,
                   const char *name,
                   pid_t *pid)
{
    int rc;
    FILE *file;
    char *pidfile = NULL;
    *pid = 0;
1885

1886 1887 1888 1889 1890
    if (name == NULL || dir == NULL) {
        rc = EINVAL;
        goto cleanup;
    }

1891
    if (!(pidfile = virFilePid(dir, name))) {
1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902
        rc = ENOMEM;
        goto cleanup;
    }

    if (!(file = fopen(pidfile, "r"))) {
        rc = errno;
        goto cleanup;
    }

    if (fscanf(file, "%d", pid) != 1) {
        rc = EINVAL;
1903
        VIR_FORCE_FCLOSE(file);
1904 1905 1906
        goto cleanup;
    }

1907
    if (VIR_FCLOSE(file) < 0) {
1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924
        rc = errno;
        goto cleanup;
    }

    rc = 0;

 cleanup:
    VIR_FREE(pidfile);
    return rc;
}

int virFileDeletePid(const char *dir,
                     const char *name)
{
    int rc = 0;
    char *pidfile = NULL;

1925 1926 1927 1928 1929
    if (name == NULL || dir == NULL) {
        rc = EINVAL;
        goto cleanup;
    }

1930 1931
    if (!(pidfile = virFilePid(dir, name))) {
        rc = ENOMEM;
1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943
        goto cleanup;
    }

    if (unlink(pidfile) < 0 && errno != ENOENT)
        rc = errno;

cleanup:
    VIR_FREE(pidfile);
    return rc;
}


A
Amy Griffis 已提交
1944
/*
E
Eric Blake 已提交
1945
 * Creates an absolute path for a potentially relative path.
A
Amy Griffis 已提交
1946 1947 1948 1949 1950 1951 1952 1953 1954 1955
 * Return 0 if the path was not relative, or on success.
 * Return -1 on error.
 *
 * You must free the result.
 */
int virFileAbsPath(const char *path, char **abspath)
{
    char *buf;

    if (path[0] == '/') {
1956 1957
        if (!(*abspath = strdup(path)))
            return -1;
A
Amy Griffis 已提交
1958 1959 1960
    } else {
        buf = getcwd(NULL, 0);
        if (buf == NULL)
1961
            return -1;
A
Amy Griffis 已提交
1962

1963
        if (virAsprintf(abspath, "%s/%s", buf, path) < 0) {
A
Amy Griffis 已提交
1964
            VIR_FREE(buf);
1965
            return -1;
A
Amy Griffis 已提交
1966
        }
1967
        VIR_FREE(buf);
A
Amy Griffis 已提交
1968 1969 1970 1971
    }

    return 0;
}
1972

1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021
/* Remove spurious / characters from a path. The result must be freed */
char *
virFileSanitizePath(const char *path)
{
    const char *cur = path;
    char *cleanpath;
    int idx = 0;

    cleanpath = strdup(path);
    if (!cleanpath) {
        virReportOOMError();
        return NULL;
    }

    /* Need to sanitize:
     * //           -> //
     * ///          -> /
     * /../foo      -> /../foo
     * /foo///bar/  -> /foo/bar
     */

    /* Starting with // is valid posix, but ///foo == /foo */
    if (cur[0] == '/' && cur[1] == '/' && cur[2] != '/') {
        idx = 2;
        cur += 2;
    }

    /* Sanitize path in place */
    while (*cur != '\0') {
        if (*cur != '/') {
            cleanpath[idx++] = *cur++;
            continue;
        }

        /* Skip all extra / */
        while (*++cur == '/')
            continue;

        /* Don't add a trailing / */
        if (idx != 0 && *cur == '\0')
            break;

        cleanpath[idx++] = '/';
    }
    cleanpath[idx] = '\0';

    return cleanpath;
}

2022 2023 2024 2025 2026 2027 2028
/* Like strtol, but produce an "int" result, and check more carefully.
   Return 0 upon success;  return -1 to indicate failure.
   When END_PTR is NULL, the byte after the final valid digit must be NUL.
   Otherwise, it's like strtol and lets the caller check any suffix for
   validity.  This function is careful to return -1 when the string S
   represents a number that is not representable as an "int". */
int
D
Daniel P. Berrange 已提交
2029
virStrToLong_i(char const *s, char **end_ptr, int base, int *result)
2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064
{
    long int val;
    char *p;
    int err;

    errno = 0;
    val = strtol(s, &p, base);
    err = (errno || (!end_ptr && *p) || p == s || (int) val != val);
    if (end_ptr)
        *end_ptr = p;
    if (err)
        return -1;
    *result = val;
    return 0;
}

/* Just like virStrToLong_i, above, but produce an "unsigned int" value.  */
int
virStrToLong_ui(char const *s, char **end_ptr, int base, unsigned int *result)
{
    unsigned long int val;
    char *p;
    int err;

    errno = 0;
    val = strtoul(s, &p, base);
    err = (errno || (!end_ptr && *p) || p == s || (unsigned int) val != val);
    if (end_ptr)
        *end_ptr = p;
    if (err)
        return -1;
    *result = val;
    return 0;
}

2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103
/* Just like virStrToLong_i, above, but produce a "long" value.  */
int
virStrToLong_l(char const *s, char **end_ptr, int base, long *result)
{
    long int val;
    char *p;
    int err;

    errno = 0;
    val = strtol(s, &p, base);
    err = (errno || (!end_ptr && *p) || p == s);
    if (end_ptr)
        *end_ptr = p;
    if (err)
        return -1;
    *result = val;
    return 0;
}

/* Just like virStrToLong_i, above, but produce an "unsigned long" value.  */
int
virStrToLong_ul(char const *s, char **end_ptr, int base, unsigned long *result)
{
    unsigned long int val;
    char *p;
    int err;

    errno = 0;
    val = strtoul(s, &p, base);
    err = (errno || (!end_ptr && *p) || p == s);
    if (end_ptr)
        *end_ptr = p;
    if (err)
        return -1;
    *result = val;
    return 0;
}

/* Just like virStrToLong_i, above, but produce a "long long" value.  */
2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123
int
virStrToLong_ll(char const *s, char **end_ptr, int base, long long *result)
{
    long long val;
    char *p;
    int err;

    errno = 0;
    val = strtoll(s, &p, base);
    err = (errno || (!end_ptr && *p) || p == s || (long long) val != val);
    if (end_ptr)
        *end_ptr = p;
    if (err)
        return -1;
    *result = val;
    return 0;
}

/* Just like virStrToLong_i, above, but produce an "unsigned long long" value.  */
int
D
Daniel P. Berrange 已提交
2124
virStrToLong_ull(char const *s, char **end_ptr, int base, unsigned long long *result)
2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139
{
    unsigned long long val;
    char *p;
    int err;

    errno = 0;
    val = strtoull(s, &p, base);
    err = (errno || (!end_ptr && *p) || p == s || (unsigned long long) val != val);
    if (end_ptr)
        *end_ptr = p;
    if (err)
        return -1;
    *result = val;
    return 0;
}
2140

2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160
int
virStrToDouble(char const *s,
               char **end_ptr,
               double *result)
{
    double val;
    char *p;
    int err;

    errno = 0;
    val = strtod(s, &p);
    err = (errno || (!end_ptr && *p) || p == s);
    if (end_ptr)
        *end_ptr = p;
    if (err)
        return -1;
    *result = val;
    return 0;
}

2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175
/* Convert C from hexadecimal character to integer.  */
int
virHexToBin(unsigned char c)
{
    switch (c) {
    default: return c - '0';
    case 'a': case 'A': return 10;
    case 'b': case 'B': return 11;
    case 'c': case 'C': return 12;
    case 'd': case 'D': return 13;
    case 'e': case 'E': return 14;
    case 'f': case 'F': return 15;
    }
}

2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212
/**
 * virSkipSpaces:
 * @str: pointer to the char pointer used
 *
 * Skip potential blanks, this includes space tabs, line feed,
 * carriage returns and also '\\' which can be erronously emitted
 * by xend
 */
void
virSkipSpaces(const char **str)
{
    const char *cur = *str;

    while ((*cur == ' ') || (*cur == '\t') || (*cur == '\n') ||
           (*cur == '\r') || (*cur == '\\'))
        cur++;
    *str = cur;
}

/**
 * virParseNumber:
 * @str: pointer to the char pointer used
 *
 * Parse an unsigned number
 *
 * Returns the unsigned number or -1 in case of error. @str will be
 *         updated to skip the number.
 */
int
virParseNumber(const char **str)
{
    int ret = 0;
    const char *cur = *str;

    if ((*cur < '0') || (*cur > '9'))
        return (-1);

J
Jim Meyering 已提交
2213
    while (c_isdigit(*cur)) {
2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224
        unsigned int c = *cur - '0';

        if ((ret > INT_MAX / 10) ||
            ((ret == INT_MAX / 10) && (c > INT_MAX % 10)))
            return (-1);
        ret = ret * 10 + c;
        cur++;
    }
    *str = cur;
    return (ret);
}
2225

2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260

/**
 * virParseVersionString:
 * @str: const char pointer to the version string
 * @version: unsigned long pointer to output the version number
 *
 * Parse an unsigned version number from a version string. Expecting
 * 'major.minor.micro' format, ignoring an optional suffix.
 *
 * The major, minor and micro numbers are encoded into a single version number:
 *
 *   1000000 * major + 1000 * minor + micro
 *
 * Returns the 0 for success, -1 for error.
 */
int
virParseVersionString(const char *str, unsigned long *version)
{
    unsigned int major, minor, micro;
    char *tmp;

    if (virStrToLong_ui(str, &tmp, 10, &major) < 0 || *tmp != '.')
        return -1;

    if (virStrToLong_ui(tmp + 1, &tmp, 10, &minor) < 0 || *tmp != '.')
        return -1;

    if (virStrToLong_ui(tmp + 1, &tmp, 10, &micro) < 0)
        return -1;

    *version = 1000000 * major + 1000 * minor + micro;

    return 0;
}

E
Eric Blake 已提交
2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276
/**
 * virVasprintf
 *
 * like glibc's vasprintf but makes sure *strp == NULL on failure
 */
int
virVasprintf(char **strp, const char *fmt, va_list list)
{
    int ret;

    if ((ret = vasprintf(strp, fmt, list)) == -1)
        *strp = NULL;

    return ret;
}

G
Guido Günther 已提交
2277 2278 2279
/**
 * virAsprintf
 *
2280
 * like glibc's_asprintf but makes sure *strp == NULL on failure
G
Guido Günther 已提交
2281
 */
2282
int
G
Guido Günther 已提交
2283 2284 2285 2286 2287 2288
virAsprintf(char **strp, const char *fmt, ...)
{
    va_list ap;
    int ret;

    va_start(ap, fmt);
E
Eric Blake 已提交
2289
    ret = virVasprintf(strp, fmt, ap);
G
Guido Günther 已提交
2290 2291 2292 2293
    va_end(ap);
    return ret;
}

C
Chris Lalancette 已提交
2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336
/**
 * virStrncpy
 *
 * A safe version of strncpy.  The last parameter is the number of bytes
 * available in the destination string, *not* the number of bytes you want
 * to copy.  If the destination is not large enough to hold all n of the
 * src string bytes plus a \0, NULL is returned and no data is copied.
 * If the destination is large enough to hold the n bytes plus \0, then the
 * string is copied and a pointer to the destination string is returned.
 */
char *
virStrncpy(char *dest, const char *src, size_t n, size_t destbytes)
{
    char *ret;

    if (n > (destbytes - 1))
        return NULL;

    ret = strncpy(dest, src, n);
    /* strncpy NULL terminates iff the last character is \0.  Therefore
     * force the last byte to be \0
     */
    dest[n] = '\0';

    return ret;
}

/**
 * virStrcpy
 *
 * A safe version of strcpy.  The last parameter is the number of bytes
 * available in the destination string, *not* the number of bytes you want
 * to copy.  If the destination is not large enough to hold all n of the
 * src string bytes plus a \0, NULL is returned and no data is copied.
 * If the destination is large enough to hold the source plus \0, then the
 * string is copied and a pointer to the destination string is returned.
 */
char *
virStrcpy(char *dest, const char *src, size_t destbytes)
{
    return virStrncpy(dest, src, strlen(src), destbytes);
}

2337 2338
/* Compare two MAC addresses, ignoring differences in case,
 * as well as leading zeros.
2339 2340
 */
int
D
Daniel P. Berrange 已提交
2341
virMacAddrCompare (const char *p, const char *q)
2342
{
2343 2344
    unsigned char c, d;
    do {
2345
        while (*p == '0' && c_isxdigit (p[1]))
2346
            ++p;
2347
        while (*q == '0' && c_isxdigit (q[1]))
2348
            ++q;
2349 2350
        c = c_tolower (*p);
        d = c_tolower (*q);
2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365

        if (c == 0 || d == 0)
            break;

        ++p;
        ++q;
    } while (c == d);

    if (UCHAR_MAX <= INT_MAX)
        return c - d;

    /* On machines where 'char' and 'int' are types of the same size, the
       difference of two 'unsigned char' values - including the sign bit -
       doesn't fit in an 'int'.  */
    return (c > d ? 1 : c < d ? -1 : 0);
2366 2367
}

2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382
/**
 * virParseMacAddr:
 * @str: string representation of MAC address, e.g., "0:1E:FC:E:3a:CB"
 * @addr: 6-byte MAC address
 *
 * Parse a MAC address
 *
 * Return 0 upon success, or -1 in case of error.
 */
int
virParseMacAddr(const char* str, unsigned char *addr)
{
    int i;

    errno = 0;
2383
    for (i = 0; i < VIR_MAC_BUFLEN; i++) {
2384 2385 2386 2387 2388 2389
        char *end_ptr;
        unsigned long result;

        /* This is solely to avoid accepting the leading
         * space or "+" that strtoul would otherwise accept.
         */
2390
        if (!c_isxdigit(*str))
2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401
            break;

        result = strtoul(str, &end_ptr, 16);

        if ((end_ptr - str) < 1 || 2 < (end_ptr - str) ||
            (errno != 0) ||
            (0xFF < result))
            break;

        addr[i] = (unsigned char) result;

2402 2403 2404 2405
        if ((i == 5) && (*end_ptr == '\0'))
            return 0;
        if (*end_ptr != ':')
            break;
2406 2407 2408 2409 2410 2411

        str = end_ptr + 1;
    }

    return -1;
}
2412

2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428
void virFormatMacAddr(const unsigned char *addr,
                      char *str)
{
    snprintf(str, VIR_MAC_STRING_BUFLEN,
             "%02X:%02X:%02X:%02X:%02X:%02X",
             addr[0], addr[1], addr[2],
             addr[3], addr[4], addr[5]);
    str[VIR_MAC_STRING_BUFLEN-1] = '\0';
}

void virGenerateMacAddr(const unsigned char *prefix,
                        unsigned char *addr)
{
    addr[0] = prefix[0];
    addr[1] = prefix[1];
    addr[2] = prefix[2];
2429 2430 2431
    addr[3] = virRandom(256);
    addr[4] = virRandom(256);
    addr[5] = virRandom(256);
2432 2433 2434
}


2435 2436 2437 2438 2439
int virEnumFromString(const char *const*types,
                      unsigned int ntypes,
                      const char *type)
{
    unsigned int i;
2440 2441 2442
    if (!type)
        return -1;

2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459
    for (i = 0 ; i < ntypes ; i++)
        if (STREQ(types[i], type))
            return i;

    return -1;
}

const char *virEnumToString(const char *const*types,
                            unsigned int ntypes,
                            int type)
{
    if (type < 0 || type >= ntypes)
        return NULL;

    return types[type];
}

2460 2461 2462
/* Translates a device name of the form (regex) /^[fhv]d[a-z]+[0-9]*$/
 * into the corresponding index (e.g. sda => 0, hdz => 25, vdaa => 26)
 * Note that any trailing string of digits is simply ignored.
2463 2464 2465 2466 2467 2468
 * @param name The name of the device
 * @return name's index, or -1 on failure
 */
int virDiskNameToIndex(const char *name) {
    const char *ptr = NULL;
    int idx = 0;
2469
    static char const* const drive_prefix[] = {"fd", "hd", "vd", "sd", "xvd", "ubd"};
2470
    unsigned int i;
2471

2472 2473 2474
    for (i = 0; i < ARRAY_CARDINALITY(drive_prefix); i++) {
        if (STRPREFIX(name, drive_prefix[i])) {
            ptr = name + strlen(drive_prefix[i]);
2475
            break;
2476
        }
2477 2478
    }

2479
    if (!ptr)
2480 2481
        return -1;

D
Daniel Veillard 已提交
2482
    for (i = 0; *ptr; i++) {
2483
        idx = (idx + (i < 1 ? 0 : 1)) * 26;
2484

J
Jim Meyering 已提交
2485
        if (!c_islower(*ptr))
2486
            break;
2487 2488 2489 2490 2491

        idx += *ptr - 'a';
        ptr++;
    }

2492 2493 2494 2495 2496
    /* Count the trailing digits.  */
    size_t n_digits = strspn(ptr, "0123456789");
    if (ptr[n_digits] != '\0')
        return -1;

2497 2498
    return idx;
}
G
Guido Günther 已提交
2499

2500 2501 2502 2503 2504 2505
char *virIndexToDiskName(int idx, const char *prefix)
{
    char *name = NULL;
    int i, k, offset;

    if (idx < 0) {
2506 2507
        virUtilError(VIR_ERR_INTERNAL_ERROR,
                     _("Disk index %d is negative"), idx);
2508 2509 2510 2511 2512 2513 2514 2515
        return NULL;
    }

    for (i = 0, k = idx; k >= 0; ++i, k = k / 26 - 1) { }

    offset = strlen(prefix);

    if (VIR_ALLOC_N(name, offset + i + 1)) {
2516
        virReportOOMError();
2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529
        return NULL;
    }

    strcpy(name, prefix);
    name[offset + i] = '\0';

    for (i = i - 1, k = idx; k >= 0; --i, k = k / 26 - 1) {
        name[offset + i] = 'a' + (k % 26);
    }

    return name;
}

2530
#ifndef AI_CANONIDN
2531
# define AI_CANONIDN 0
2532 2533
#endif

C
Chris Lalancette 已提交
2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554
/* Who knew getting a hostname could be so delicate.  In Linux (and Unices
 * in general), many things depend on "hostname" returning a value that will
 * resolve one way or another.  In the modern world where networks frequently
 * come and go this is often being hard-coded to resolve to "localhost".  If
 * it *doesn't* resolve to localhost, then we would prefer to have the FQDN.
 * That leads us to 3 possibilities:
 *
 * 1)  gethostname() returns an FQDN (not localhost) - we return the string
 *     as-is, it's all of the information we want
 * 2)  gethostname() returns "localhost" - we return localhost; doing further
 *     work to try to resolve it is pointless
 * 3)  gethostname() returns a shortened hostname - in this case, we want to
 *     try to resolve this to a fully-qualified name.  Therefore we pass it
 *     to getaddrinfo().  There are two possible responses:
 *     a)  getaddrinfo() resolves to a FQDN - return the FQDN
 *     b)  getaddrinfo() resolves to localhost - in this case, the data we got
 *         from gethostname() is actually more useful than what we got from
 *         getaddrinfo().  Return the value from gethostname() and hope for
 *         the best.
 */
char *virGetHostname(virConnectPtr conn ATTRIBUTE_UNUSED)
2555 2556 2557
{
    int r;
    char hostname[HOST_NAME_MAX+1], *result;
C
Chris Lalancette 已提交
2558
    struct addrinfo hints, *info;
2559 2560

    r = gethostname (hostname, sizeof(hostname));
2561
    if (r == -1) {
2562 2563
        virReportSystemError(errno,
                             "%s", _("failed to determine host name"));
2564
        return NULL;
2565
    }
2566 2567
    NUL_TERMINATE(hostname);

C
Chris Lalancette 已提交
2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582
    if (STRPREFIX(hostname, "localhost") || strchr(hostname, '.')) {
        /* in this case, gethostname returned localhost (meaning we can't
         * do any further canonicalization), or it returned an FQDN (and
         * we don't need to do any further canonicalization).  Return the
         * string as-is; it's up to callers to check whether "localhost"
         * is allowed.
         */
        result = strdup(hostname);
        goto check_and_return;
    }

    /* otherwise, it's a shortened, non-localhost, hostname.  Attempt to
     * canonicalize the hostname by running it through getaddrinfo
     */

2583 2584 2585 2586
    memset(&hints, 0, sizeof(hints));
    hints.ai_flags = AI_CANONNAME|AI_CANONIDN;
    hints.ai_family = AF_UNSPEC;
    r = getaddrinfo(hostname, NULL, &hints, &info);
2587
    if (r != 0) {
2588 2589 2590
        virUtilError(VIR_ERR_INTERNAL_ERROR,
                     _("getaddrinfo failed for '%s': %s"),
                     hostname, gai_strerror(r));
2591
        return NULL;
2592
    }
2593

2594 2595 2596
    /* Tell static analyzers about getaddrinfo semantics.  */
    sa_assert (info);

C
Chris Lalancette 已提交
2597 2598 2599 2600 2601 2602 2603 2604 2605 2606
    if (info->ai_canonname == NULL ||
        STRPREFIX(info->ai_canonname, "localhost"))
        /* in this case, we tried to canonicalize and we ended up back with
         * localhost.  Ignore the canonicalized name and just return the
         * original hostname
         */
        result = strdup(hostname);
    else
        /* Caller frees this string. */
        result = strdup (info->ai_canonname);
2607

C
Chris Lalancette 已提交
2608
    freeaddrinfo(info);
2609

C
Chris Lalancette 已提交
2610 2611
check_and_return:
    if (result == NULL)
2612
        virReportOOMError();
2613 2614 2615
    return result;
}

G
Guido Günther 已提交
2616 2617 2618
/* send signal to a single process */
int virKillProcess(pid_t pid, int sig)
{
2619
    if (pid <= 1) {
G
Guido Günther 已提交
2620 2621 2622 2623
        errno = ESRCH;
        return -1;
    }

2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667
#ifdef WIN32
    /* Mingw / Windows don't have many signals (AFAIK) */
    switch (sig) {
    case SIGINT:
        /* This does a Ctrl+C equiv */
        if (!GenerateConsoleCtrlEvent(CTRL_C_EVENT, pid)) {
            errno = ESRCH;
            return -1;
        }
        break;

    case SIGTERM:
        /* Since TerminateProcess is closer to SIG_KILL, we do
         * a Ctrl+Break equiv which is more pleasant like the
         * good old unix SIGTERM/HUP
         */
        if (!GenerateConsoleCtrlEvent(CTRL_BREAK_EVENT, pid)) {
            errno = ESRCH;
            return -1;
        }
        break;

    default:
    {
        HANDLE proc;
        proc = OpenProcess(PROCESS_TERMINATE, FALSE, pid);
        if (!proc) {
            errno = ESRCH; /* Not entirely accurate, but close enough */
            return -1;
        }

        /*
         * TerminateProcess is more or less equiv to SIG_KILL, in that
         * a process can't trap / block it
         */
        if (!TerminateProcess(proc, sig)) {
            errno = ESRCH;
            return -1;
        }
        CloseHandle(proc);
    }
    }
    return 0;
#else
G
Guido Günther 已提交
2668
    return kill(pid, sig);
2669
#endif
G
Guido Günther 已提交
2670
}
2671 2672


2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702
static char randomState[128];
static struct random_data randomData;
static virMutex randomLock;

int virRandomInitialize(unsigned int seed)
{
    if (virMutexInit(&randomLock) < 0)
        return -1;

    if (initstate_r(seed,
                    randomState,
                    sizeof(randomState),
                    &randomData) < 0)
        return -1;

    return 0;
}

int virRandom(int max)
{
    int32_t ret;

    virMutexLock(&randomLock);
    random_r(&randomData, &ret);
    virMutexUnlock(&randomLock);

    return (int) ((double)max * ((double)ret / (double)RAND_MAX));
}


2703
#ifdef HAVE_GETPWUID_R
2704 2705 2706 2707 2708
enum {
    VIR_USER_ENT_DIRECTORY,
    VIR_USER_ENT_NAME,
};

2709
static char *virGetUserEnt(uid_t uid,
2710
                           int field)
2711 2712 2713 2714
{
    char *strbuf;
    char *ret;
    struct passwd pwbuf;
2715
    struct passwd *pw = NULL;
2716 2717
    long val = sysconf(_SC_GETPW_R_SIZE_MAX);
    size_t strbuflen = val;
2718
    int rc;
2719

2720 2721 2722
    /* sysconf is a hint; if it fails, fall back to a reasonable size */
    if (val < 0)
        strbuflen = 1024;
2723 2724

    if (VIR_ALLOC_N(strbuf, strbuflen) < 0) {
2725
        virReportOOMError();
2726 2727 2728
        return NULL;
    }

2729 2730 2731 2732 2733 2734 2735
    /*
     * From the manpage (terrifying but true):
     *
     * ERRORS
     *  0 or ENOENT or ESRCH or EBADF or EPERM or ...
     *        The given name or uid was not found.
     */
2736 2737 2738 2739 2740 2741 2742 2743 2744
    while ((rc = getpwuid_r(uid, &pwbuf, strbuf, strbuflen, &pw)) == ERANGE) {
        if (VIR_RESIZE_N(strbuf, strbuflen, strbuflen, strbuflen) < 0) {
            virReportOOMError();
            VIR_FREE(strbuf);
            return NULL;
        }
    }
    if (rc != 0 || pw == NULL) {
        virReportSystemError(rc,
E
Eric Blake 已提交
2745 2746
                             _("Failed to find user record for uid '%u'"),
                             (unsigned int) uid);
2747 2748 2749 2750
        VIR_FREE(strbuf);
        return NULL;
    }

2751 2752 2753 2754
    if (field == VIR_USER_ENT_DIRECTORY)
        ret = strdup(pw->pw_dir);
    else
        ret = strdup(pw->pw_name);
2755 2756 2757

    VIR_FREE(strbuf);
    if (!ret)
2758
        virReportOOMError();
2759 2760 2761

    return ret;
}
2762

2763
char *virGetUserDirectory(uid_t uid)
2764
{
2765
    return virGetUserEnt(uid, VIR_USER_ENT_DIRECTORY);
2766 2767
}

2768
char *virGetUserName(uid_t uid)
2769
{
2770
    return virGetUserEnt(uid, VIR_USER_ENT_NAME);
2771 2772
}

2773

2774
int virGetUserID(const char *name,
2775 2776 2777 2778 2779
                 uid_t *uid)
{
    char *strbuf;
    struct passwd pwbuf;
    struct passwd *pw = NULL;
2780 2781
    long val = sysconf(_SC_GETPW_R_SIZE_MAX);
    size_t strbuflen = val;
2782
    int rc;
2783

2784 2785 2786
    /* sysconf is a hint; if it fails, fall back to a reasonable size */
    if (val < 0)
        strbuflen = 1024;
2787 2788

    if (VIR_ALLOC_N(strbuf, strbuflen) < 0) {
2789
        virReportOOMError();
2790 2791 2792 2793 2794 2795 2796 2797 2798 2799
        return -1;
    }

    /*
     * From the manpage (terrifying but true):
     *
     * ERRORS
     *  0 or ENOENT or ESRCH or EBADF or EPERM or ...
     *        The given name or uid was not found.
     */
2800 2801 2802 2803 2804 2805 2806 2807 2808
    while ((rc = getpwnam_r(name, &pwbuf, strbuf, strbuflen, &pw)) == ERANGE) {
        if (VIR_RESIZE_N(strbuf, strbuflen, strbuflen, strbuflen) < 0) {
            virReportOOMError();
            VIR_FREE(strbuf);
            return -1;
        }
    }
    if (rc != 0 || pw == NULL) {
        virReportSystemError(rc,
2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822
                             _("Failed to find user record for name '%s'"),
                             name);
        VIR_FREE(strbuf);
        return -1;
    }

    *uid = pw->pw_uid;

    VIR_FREE(strbuf);

    return 0;
}


2823
int virGetGroupID(const char *name,
2824 2825 2826 2827 2828
                  gid_t *gid)
{
    char *strbuf;
    struct group grbuf;
    struct group *gr = NULL;
2829 2830
    long val = sysconf(_SC_GETGR_R_SIZE_MAX);
    size_t strbuflen = val;
2831
    int rc;
2832

2833 2834 2835
    /* sysconf is a hint; if it fails, fall back to a reasonable size */
    if (val < 0)
        strbuflen = 1024;
2836 2837

    if (VIR_ALLOC_N(strbuf, strbuflen) < 0) {
2838
        virReportOOMError();
2839 2840 2841 2842 2843 2844 2845 2846 2847 2848
        return -1;
    }

    /*
     * From the manpage (terrifying but true):
     *
     * ERRORS
     *  0 or ENOENT or ESRCH or EBADF or EPERM or ...
     *        The given name or uid was not found.
     */
2849 2850 2851 2852 2853 2854 2855 2856 2857
    while ((rc = getgrnam_r(name, &grbuf, strbuf, strbuflen, &gr)) == ERANGE) {
        if (VIR_RESIZE_N(strbuf, strbuflen, strbuflen, strbuflen) < 0) {
            virReportOOMError();
            VIR_FREE(strbuf);
            return -1;
        }
    }
    if (rc != 0 || gr == NULL) {
        virReportSystemError(rc,
2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869
                             _("Failed to find group record for name '%s'"),
                             name);
        VIR_FREE(strbuf);
        return -1;
    }

    *gid = gr->gr_gid;

    VIR_FREE(strbuf);

    return 0;
}
2870

L
Laine Stump 已提交
2871 2872 2873

/* Set the real and effective uid and gid to the given values, and call
 * initgroups so that the process has all the assumed group membership of
2874 2875
 * that uid. return 0 on success, -1 on failure (the original system error
 * remains in errno).
L
Laine Stump 已提交
2876 2877 2878 2879
 */
int
virSetUIDGID(uid_t uid, gid_t gid)
{
2880 2881
    int err;

L
Laine Stump 已提交
2882 2883
    if (gid > 0) {
        if (setregid(gid, gid) < 0) {
2884
            virReportSystemError(err = errno,
E
Eric Blake 已提交
2885 2886
                                 _("cannot change to '%d' group"),
                                 (unsigned int) gid);
2887
            goto error;
L
Laine Stump 已提交
2888 2889 2890 2891 2892 2893 2894 2895
        }
    }

    if (uid > 0) {
# ifdef HAVE_INITGROUPS
        struct passwd pwd, *pwd_result;
        char *buf = NULL;
        size_t bufsize;
2896
        int rc;
L
Laine Stump 已提交
2897 2898 2899 2900 2901 2902 2903

        bufsize = sysconf(_SC_GETPW_R_SIZE_MAX);
        if (bufsize == -1)
            bufsize = 16384;

        if (VIR_ALLOC_N(buf, bufsize) < 0) {
            virReportOOMError();
2904 2905
            err = ENOMEM;
            goto error;
L
Laine Stump 已提交
2906
        }
2907 2908 2909 2910 2911
        while ((rc = getpwuid_r(uid, &pwd, buf, bufsize,
                                &pwd_result)) == ERANGE) {
            if (VIR_RESIZE_N(buf, bufsize, bufsize, bufsize) < 0) {
                virReportOOMError();
                VIR_FREE(buf);
2912 2913
                err = ENOMEM;
                goto error;
2914 2915 2916
            }
        }
        if (rc || !pwd_result) {
2917
            virReportSystemError(err = rc, _("cannot getpwuid_r(%d)"),
E
Eric Blake 已提交
2918
                                 (unsigned int) uid);
L
Laine Stump 已提交
2919
            VIR_FREE(buf);
2920
            goto error;
L
Laine Stump 已提交
2921 2922
        }
        if (initgroups(pwd.pw_name, pwd.pw_gid) < 0) {
2923
            virReportSystemError(err = errno,
L
Laine Stump 已提交
2924
                                 _("cannot initgroups(\"%s\", %d)"),
E
Eric Blake 已提交
2925
                                 pwd.pw_name, (unsigned int) pwd.pw_gid);
L
Laine Stump 已提交
2926
            VIR_FREE(buf);
2927
            goto error;
L
Laine Stump 已提交
2928 2929 2930 2931
        }
        VIR_FREE(buf);
# endif
        if (setreuid(uid, uid) < 0) {
2932
            virReportSystemError(err = errno,
E
Eric Blake 已提交
2933 2934
                                 _("cannot change to uid to '%d'"),
                                 (unsigned int) uid);
2935
            goto error;
L
Laine Stump 已提交
2936 2937 2938
        }
    }
    return 0;
2939 2940 2941 2942

error:
    errno = err;
    return -1;
L
Laine Stump 已提交
2943 2944
}

2945 2946 2947 2948 2949 2950
#else /* HAVE_GETPWUID_R */

char *
virGetUserDirectory(uid_t uid ATTRIBUTE_UNUSED)
{
    virUtilError(VIR_ERR_INTERNAL_ERROR,
M
Matthias Bolte 已提交
2951
                 "%s", _("virGetUserDirectory is not available"));
2952 2953 2954 2955 2956 2957 2958 2959

    return NULL;
}

char *
virGetUserName(uid_t uid ATTRIBUTE_UNUSED)
{
    virUtilError(VIR_ERR_INTERNAL_ERROR,
M
Matthias Bolte 已提交
2960
                 "%s", _("virGetUserName is not available"));
2961 2962 2963 2964 2965 2966 2967 2968

    return NULL;
}

int virGetUserID(const char *name ATTRIBUTE_UNUSED,
                 uid_t *uid ATTRIBUTE_UNUSED)
{
    virUtilError(VIR_ERR_INTERNAL_ERROR,
M
Matthias Bolte 已提交
2969
                 "%s", _("virGetUserID is not available"));
2970 2971 2972 2973 2974 2975 2976 2977 2978

    return 0;
}


int virGetGroupID(const char *name ATTRIBUTE_UNUSED,
                  gid_t *gid ATTRIBUTE_UNUSED)
{
    virUtilError(VIR_ERR_INTERNAL_ERROR,
M
Matthias Bolte 已提交
2979
                 "%s", _("virGetGroupID is not available"));
2980 2981 2982

    return 0;
}
L
Laine Stump 已提交
2983 2984 2985 2986 2987 2988 2989 2990 2991

int
virSetUIDGID(uid_t uid ATTRIBUTE_UNUSED,
             gid_t gid ATTRIBUTE_UNUSED)
{
    virUtilError(VIR_ERR_INTERNAL_ERROR,
                 "%s", _("virSetUIDGID is not available"));
    return -1;
}
2992
#endif /* HAVE_GETPWUID_R */
2993 2994


2995
#if defined HAVE_MNTENT_H && defined HAVE_GETMNTENT_R
2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025
/* search /proc/mounts for mount point of *type; return pointer to
 * malloc'ed string of the path if found, otherwise return NULL
 * with errno set to an appropriate value.
 */
char *virFileFindMountPoint(const char *type)
{
    FILE *f;
    struct mntent mb;
    char mntbuf[1024];
    char *ret = NULL;

    f = setmntent("/proc/mounts", "r");
    if (!f)
        return NULL;

    while (getmntent_r(f, &mb, mntbuf, sizeof(mntbuf))) {
        if (STREQ(mb.mnt_type, type)) {
            ret = strdup(mb.mnt_dir);
            goto cleanup;
        }
    }

    if (!ret)
        errno = ENOENT;

cleanup:
    endmntent(f);

    return ret;
}
3026

3027
#else /* defined HAVE_MNTENT_H && defined HAVE_GETMNTENT_R */
3028 3029 3030 3031 3032 3033 3034 3035 3036

char *
virFileFindMountPoint(const char *type ATTRIBUTE_UNUSED)
{
    errno = ENOSYS;

    return NULL;
}

3037
#endif /* defined HAVE_MNTENT_H && defined HAVE_GETMNTENT_R */
D
Daniel P. Berrange 已提交
3038

3039
#if defined(UDEVADM) || defined(UDEVSETTLE)
3040
void virFileWaitForDevices(void)
D
Daniel P. Berrange 已提交
3041
{
3042
# ifdef UDEVADM
D
Daniel P. Berrange 已提交
3043
    const char *const settleprog[] = { UDEVADM, "settle", NULL };
3044
# else
D
Daniel P. Berrange 已提交
3045
    const char *const settleprog[] = { UDEVSETTLE, NULL };
3046
# endif
D
Daniel P. Berrange 已提交
3047 3048 3049 3050 3051 3052 3053 3054 3055 3056 3057
    int exitstatus;

    if (access(settleprog[0], X_OK) != 0)
        return;

    /*
     * NOTE: we ignore errors here; this is just to make sure that any device
     * nodes that are being created finish before we try to scan them.
     * If this fails for any reason, we still have the backup of polling for
     * 5 seconds for device nodes.
     */
3058
    if (virRun(settleprog, &exitstatus) < 0)
3059
    {}
D
Daniel P. Berrange 已提交
3060
}
3061
#else
3062
void virFileWaitForDevices(void) {}
D
Daniel P. Berrange 已提交
3063
#endif
3064 3065 3066 3067 3068 3069 3070 3071

int virBuildPathInternal(char **path, ...)
{
    char *path_component = NULL;
    virBuffer buf = VIR_BUFFER_INITIALIZER;
    va_list ap;
    int ret = 0;

E
Eric Blake 已提交
3072
    va_start(ap, path);
3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091

    path_component = va_arg(ap, char *);
    virBufferAdd(&buf, path_component, -1);

    while ((path_component = va_arg(ap, char *)) != NULL)
    {
        virBufferAddChar(&buf, '/');
        virBufferAdd(&buf, path_component, -1);
    }

    va_end(ap);

    *path = virBufferContentAndReset(&buf);
    if (*path == NULL) {
        ret = -1;
    }

    return ret;
}
3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111

/**
 * virTimestamp:
 *
 * Return an allocated string containing the current date and time,
 * followed by ": ".  Return NULL on allocation failure.
 */
char *
virTimestamp(void)
{
    struct timeval cur_time;
    struct tm time_info;
    char timestr[100];
    char *timestamp;

    gettimeofday(&cur_time, NULL);
    localtime_r(&cur_time.tv_sec, &time_info);

    strftime(timestr, sizeof(timestr), "%Y-%m-%d %H:%M:%S", &time_info);

3112
    if (virAsprintf(&timestamp, "%s.%03d",
3113 3114 3115 3116 3117 3118
                    timestr, (int) cur_time.tv_usec / 1000) < 0) {
        return NULL;
    }

    return timestamp;
}
3119

3120
#if HAVE_LIBDEVMAPPER_H
3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131 3132
bool
virIsDevMapperDevice(const char *devname)
{
    struct stat buf;

    if (!stat(devname, &buf) &&
        S_ISBLK(buf.st_mode) &&
        dm_is_dm_major(major(buf.st_rdev)))
            return true;

    return false;
}
3133 3134 3135 3136 3137 3138
#else
bool virIsDevMapperDevice(const char *devname ATTRIBUTE_UNUSED)
{
    return false;
}
#endif
3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 3159 3160 3161 3162 3163 3164 3165 3166 3167 3168 3169 3170 3171 3172 3173 3174 3175

int virEmitXMLWarning(int fd,
                      const char *name,
                      const char *cmd) {
    size_t len;
    const char *prologue = "<!--\n\
WARNING: THIS IS AN AUTO-GENERATED FILE. CHANGES TO IT ARE LIKELY TO BE \n\
OVERWRITTEN AND LOST. Changes to this xml configuration should be made using:\n\
  virsh ";
    const char *epilogue = "\n\
or other application using the libvirt API.\n\
-->\n\n";

    if (fd < 0 || !name || !cmd)
        return -1;

    len = strlen(prologue);
    if (safewrite(fd, prologue, len) != len)
        return -1;

    len = strlen(cmd);
    if (safewrite(fd, cmd, len) != len)
        return -1;

    if (safewrite(fd, " ", 1) != 1)
        return -1;

    len = strlen(name);
    if (safewrite(fd, name, len) != len)
        return -1;

    len = strlen(epilogue);
    if (safewrite(fd, epilogue, len) != len)
        return -1;

    return 0;
}