sysutil.c

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  long local_time = vsf_sysutil_get_cached_time_sec();
  const char* p_date_format = "%b %d %H:%M";
  if (!use_localtime)
  {
    p_tm = gmtime(&p_stat->st_mtime);
  }
  else
  {
    p_tm = localtime(&p_stat->st_mtime);
  }
  /* Is this a future or 6 months old date? If so, we drop to year format */
  if (p_stat->st_mtime > local_time ||
      (local_time - p_stat->st_mtime) > 60*60*24*182)
  {
    p_date_format = "%b %d  %Y";
  }
  retval = strftime(datebuf, sizeof(datebuf), p_date_format, p_tm);
  datebuf[sizeof(datebuf)-1] = '\0';
  if (retval == 0)
  {
    die("strftime");
  }
  return datebuf;
}

const char*
vsf_sysutil_statbuf_get_numeric_date(
  const struct vsf_sysutil_statbuf* p_statbuf,
  int use_localtime)
{
  static char datebuf[15];
  const struct stat* p_stat = (const struct stat*) p_statbuf;
  struct tm* p_tm;
  int retval;
  if (!use_localtime)
  {
    p_tm = gmtime(&p_stat->st_mtime);
  }
  else
  {
    p_tm = localtime(&p_stat->st_mtime);
  }
  retval = strftime(datebuf, sizeof(datebuf), "%Y%m%d%H%M%S", p_tm);
  if (retval == 0)
  {
    die("strftime");
  }
  return datebuf;
}

filesize_t
vsf_sysutil_statbuf_get_size(const struct vsf_sysutil_statbuf* p_statbuf)
{
  const struct stat* p_stat = (const struct stat*) p_statbuf;
  if (p_stat->st_size < 0)
  {
    die("invalid inode size in vsf_sysutil_statbuf_get_size");
  }
  return p_stat->st_size;
}

int
vsf_sysutil_statbuf_get_uid(const struct vsf_sysutil_statbuf* p_statbuf)
{
  const struct stat* p_stat = (const struct stat*) p_statbuf;
  return p_stat->st_uid;
}

int
vsf_sysutil_statbuf_get_gid(const struct vsf_sysutil_statbuf* p_statbuf)
{
  const struct stat* p_stat = (const struct stat*) p_statbuf;
  return p_stat->st_gid;
}

unsigned int
vsf_sysutil_statbuf_get_links(const struct vsf_sysutil_statbuf* p_statbuf)
{
  const struct stat* p_stat = (const struct stat*) p_statbuf;
  return p_stat->st_nlink;
}

int
vsf_sysutil_statbuf_is_readable_other(
  const struct vsf_sysutil_statbuf* p_statbuf)
{
  const struct stat* p_stat = (const struct stat*) p_statbuf;
  if (p_stat->st_mode & S_IROTH)
  {
    return 1;
  }
  return 0;
}

const char*
vsf_sysutil_statbuf_get_sortkey_mtime(
  const struct vsf_sysutil_statbuf* p_statbuf)
{
  static char intbuf[32];
  const struct stat* p_stat = (const struct stat*) p_statbuf;
  /* This slight hack function must return a character date format such that
   * more recent dates appear later in the alphabet! Most notably, we must
   * make sure we pad to the same length with 0's 
   */
  snprintf(intbuf, sizeof(intbuf), "%030ld", (long) p_stat->st_mtime);
  return intbuf;
}

void
vsf_sysutil_fchown(const int fd, const int uid, const int gid)
{
  if (fchown(fd, uid, gid) != 0)
  {
    die("fchown");
  }
}

void
vsf_sysutil_fchmod(const int fd, unsigned int mode)
{
  mode = mode & 0777;
  if (fchmod(fd, mode))
  {
    die("fchmod");
  }
}

int
vsf_sysutil_chmod(const char* p_filename, unsigned int mode)
{
  /* Safety: mask "mode" to just access permissions, e.g. no suid setting! */
  mode = mode & 0777;
  return chmod(p_filename, mode);
}

int
vsf_sysutil_lock_file_write(int fd)
{
  return lock_internal(fd, F_WRLCK);
}

int
vsf_sysutil_lock_file_read(int fd)
{
  return lock_internal(fd, F_RDLCK);
}

static int
lock_internal(int fd, int lock_type)
{
  struct flock the_lock;
  int retval;
  int saved_errno;
  vsf_sysutil_memclr(&the_lock, sizeof(the_lock));
  the_lock.l_type = lock_type;
  the_lock.l_whence = SEEK_SET;
  the_lock.l_start = 0;
  the_lock.l_len = 0;
  do
  {
    retval = fcntl(fd, F_SETLKW, &the_lock);
    saved_errno = errno;
    vsf_sysutil_check_pending_actions(kVSFSysUtilUnknown, 0, 0);
  }
  while (retval < 0 && saved_errno == EINTR);
  return retval;
}

void
vsf_sysutil_unlock_file(int fd)
{
  int retval;
  struct flock the_lock;
  vsf_sysutil_memclr(&the_lock, sizeof(the_lock));
  the_lock.l_type = F_UNLCK;
  the_lock.l_whence = SEEK_SET;
  the_lock.l_start = 0;
  the_lock.l_len = 0;
  retval = fcntl(fd, F_SETLK, &the_lock);
  if (retval != 0)
  {
    die("fcntl");
  }
}

int
vsf_sysutil_readlink(const char* p_filename, char* p_dest, unsigned int bufsiz)
{
  int retval;
  if (bufsiz == 0) {
    return -1;
  }
  retval = readlink(p_filename, p_dest, bufsiz - 1);
  if (retval < 0)
  {
    return retval;
  }
  /* Ensure buffer is NULL terminated; readlink(2) doesn't do that */
  p_dest[retval] = '\0';
  return retval;
}

int
vsf_sysutil_retval_is_error(int retval)
{
  if (retval < 0)
  {
    return 1;
  }
  return 0;
}

enum EVSFSysUtilError
vsf_sysutil_get_error(void)
{
  enum EVSFSysUtilError retval = kVSFSysUtilErrUnknown;
  switch (errno)
  {
    case EADDRINUSE:
      retval = kVSFSysUtilErrADDRINUSE;
      break;
    case ENOSYS:
      retval = kVSFSysUtilErrNOSYS;
      break;
    case EINTR:
      retval = kVSFSysUtilErrINTR;
      break;
    case EINVAL:
      retval = kVSFSysUtilErrINVAL;
      break;
    case EOPNOTSUPP:
      retval = kVSFSysUtilErrOPNOTSUPP;
      break;
  }
  return retval;
}

int
vsf_sysutil_get_ipv4_sock(void)
{
  int retval = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
  if (retval < 0)
  {
    die("socket");
  }
  return retval;
}

int
vsf_sysutil_get_ipv6_sock(void)
{
  int retval = socket(PF_INET6, SOCK_STREAM, IPPROTO_TCP);
  if (retval < 0)
  {
    die("socket");
  }
  return retval;
}

struct vsf_sysutil_socketpair_retval
vsf_sysutil_unix_stream_socketpair(void)
{
  struct vsf_sysutil_socketpair_retval retval;
  int the_sockets[2];
  int sys_retval = socketpair(PF_UNIX, SOCK_STREAM, 0, the_sockets);
  if (sys_retval != 0)
  {
    die("socketpair");
  }
  retval.socket_one = the_sockets[0];
  retval.socket_two = the_sockets[1];
  return retval;
}

int
vsf_sysutil_bind(int fd, const struct vsf_sysutil_sockaddr* p_sockptr)
{
  const struct sockaddr* p_sockaddr = &p_sockptr->u.u_sockaddr;
  int len = 0;
  if (p_sockaddr->sa_family == AF_INET)
  {
    len = sizeof(struct sockaddr_in);
  }
  else if (p_sockaddr->sa_family == AF_INET6)
  {
    len = sizeof(struct sockaddr_in6);
  }
  else
  {
    die("can only support ipv4 and ipv6 currently");
  }
  return bind(fd, p_sockaddr, len);
}

int
vsf_sysutil_listen(int fd, const unsigned int backlog)
{
  int retval = listen(fd, backlog);
  if (vsf_sysutil_retval_is_error(retval) &&
      vsf_sysutil_get_error() != kVSFSysUtilErrADDRINUSE)
  {
    die("listen");
  }
  return retval;
}

/* Warning: callers of this function assume it does NOT make use of any
 * non re-entrant calls such as malloc().
 */
int
vsf_sysutil_accept_timeout(int fd, struct vsf_sysutil_sockaddr* p_sockaddr,
                           unsigned int wait_seconds)
{
  struct vsf_sysutil_sockaddr remote_addr;
  int retval;
  int saved_errno;
  fd_set accept_fdset;
  struct timeval timeout;
  unsigned int socklen = sizeof(remote_addr);
  if (p_sockaddr)
  {
    vsf_sysutil_memclr(p_sockaddr, sizeof(*p_sockaddr));
  }
  if (wait_seconds > 0)
  {
    FD_ZERO(&accept_fdset);
    FD_SET(fd, &accept_fdset);
    timeout.tv_sec = wait_seconds;
    timeout.tv_usec = 0;
    do
    {
      retval = select(fd + 1, &accept_fdset, NULL, NULL, &timeout);
      saved_errno = errno;
      vsf_sysutil_check_pending_actions(kVSFSysUtilUnknown, 0, 0);
    } while (retval < 0 && saved_errno == EINTR);
    if (retval == 0)
    {
      errno = EAGAIN;
      return -1;
    }
  }
  retval = accept(fd, &remote_addr.u.u_sockaddr, &socklen);
  vsf_sysutil_check_pending_actions(kVSFSysUtilUnknown, 0, 0);
  if (retval < 0)
  {
    return retval;
  }
  /* FreeBSD bug / paranoia: [e-mail] */
  if (socklen == 0)
  {
    return -1;
  }
  if (remote_addr.u.u_sockaddr.sa_family != AF_INET &&
      remote_addr.u.u_sockaddr.sa_family != AF_INET6)
  {
    die("can only support ipv4 and ipv6 currently");
  }
  if (p_sockaddr)
  {
    if (remote_addr.u.u_sockaddr.sa_family == AF_INET)
    {
      vsf_sysutil_memclr(&remote_addr.u.u_sockaddr_in.sin_zero,
                         sizeof(remote_addr.u.u_sockaddr_in.sin_zero));
      vsf_sysutil_memcpy(p_sockaddr, &remote_addr.u.u_sockaddr_in,
                         sizeof(remote_addr.u.u_sockaddr_in));
    }
    else
    {
      vsf_sysutil_memcpy(p_sockaddr, &remote_addr.u.u_sockaddr_in6,
                         sizeof(remote_addr.u.u_sockaddr_in6));
    }
  }
  return retval;
}

int
vsf_sysutil_connect_timeout(int fd, const struct vsf_sysutil_sockaddr* p_addr,
                            unsigned int wait_seconds)
{
  const struct sockaddr* p_sockaddr = &p_addr->u.u_sockaddr;
  unsigned int addrlen = 0;
  int retval;
  int saved_errno;
  if (p_sockaddr->sa_family == AF_INET)
  {
    addrlen = sizeof(p_addr->u.u_sockaddr_in);
  }
  else if (p_sockaddr->sa_family == AF_INET6)
  {
    addrlen = sizeof(p_addr->u.u_sockaddr_in6);
  }
  else
  {
    die("can only support ipv4 and ipv6 currently");
  }
  if (wait_seconds > 0)
  {
    vsf_sysutil_activate_noblock(fd);
  }
  retval = connect(fd, p_sockaddr, addrlen);
  if (retval < 0 && errno == EINPROGRESS)
  {
    fd_set connect_fdset;
    struct timeval timeout;
    FD_ZERO(&connect_fdset);
    FD_SET(fd, &connect_fdset);
    timeout.tv_sec = wait_seconds;
    timeout.tv_usec = 0;
    do
    {
      retval = select(fd + 1, NULL, &connect_fdset, NULL, &timeout);
      saved_errno = errno;
      vsf_sysutil_check_pending_actions(kVSFSysUtilUnknown, 0, 0);
    }
    while (retval < 0 && saved_errno == EINTR);
    if (retval == 0)
    {
      retval = -1;
      errno = EAGAIN;
    }
    else
    {
      socklen_t socklen = sizeof(retval);
      int sockoptret = getsockopt(fd, SOL_SOCKET, SO_ERROR, &retval, &socklen);
      if (sockoptret != 0)
      {
        die("getsockopt");
      }
    }
  }
  if (wait_seconds > 0)
  {
    vsf_sysutil_deactivate_noblock(fd);
  }
  return retval;
}

void
vsf_sysutil_getsockname(int fd, struct vsf_sysutil_sockaddr** p_sockptr)
{
  struct vsf_sysutil_sockaddr the_addr;
  int retval;
  unsigned int socklen = sizeof(the_addr);
  vsf_sysutil_sockaddr_clear(p_sockptr);
  retval = getsockname(fd, &the_addr.u.u_sockaddr, &socklen);
  if (retval != 0)
  {
    die("getsockname");
  }
  if (the_addr.u.u_sockaddr.sa_family != AF_INET &&
      the_addr.u.u_sockaddr.sa_family != AF_INET6)
  {
    die("can only support ipv4 and ipv6 currently");
  }
  vsf_sysutil_sockaddr_alloc(p_sockptr);
  if (socklen > sizeof(the_addr))
  {
    socklen = sizeof(the_addr);
  }
  vsf_sysutil_memcpy(*p_sockptr, &the_addr, socklen);
}

void
vsf_sysutil_getpeername(int fd, struct vsf_sysutil_sockaddr** p_sockptr)
{
  struct vsf_sysutil_sockaddr the_addr;
  int retval;
  unsigned int socklen = sizeof(the_addr);
  vsf_sysutil_sockaddr_clear(p_sockptr);
  retval = getpeername(fd, &the_addr.u.u_sockaddr, &socklen);
  if (retval != 0)
  {
    die("getpeername");
  }
  if (the_addr.u.u_sockaddr.sa_family != AF_INET &&
      the_addr.u.u_sockaddr.sa_family != AF_INET6)
  {
    die("can only support ipv4 and ipv6 currently");
  }
  vsf_sysutil_sockaddr_alloc(p_sockptr);
  if (socklen > sizeof(the_addr))
  {
    socklen = sizeof(the_addr);
  }
  vsf_sysutil_memcpy(*p_sockptr, &the_addr, socklen);
}

void
vsf_sysutil_shutdown_failok(int fd)
{
  /* SHUT_RDWR is a relatively new addition */
  #ifndef SHUT_RDWR
  #define SHUT_RDWR 2
  #endif
  (void) shutdown(fd, SHUT_RDWR);
}

void
vsf_sysutil_shutdown_read_failok(int fd)
{
  /* SHUT_RD is a relatively new addition */
  #ifndef SHUT_RD
  #define SHUT_RD 0
  #endif
  (void) shutdown(fd, SHUT_RD);
}

void
vsf_sysutil_sockaddr_clear(struct vsf_sysutil_sockaddr** p_sockptr)
{
  if (*p_sockptr != NULL)
  {
    vsf_sysutil_free(*p_sockptr);
    *p_sockptr = NULL;
  }
}

void
vsf_sysutil_sockaddr_alloc(struct vsf_sysutil_sockaddr** p_sockptr)
{
  vsf_sysutil_sockaddr_clear(p_sockptr);
  *p_sockptr = vsf_sysutil_malloc(sizeof(**p_sockptr));
  vsf_sysutil_memclr(*p_sockptr, sizeof(**p_sockptr));
}

void
vsf_sysutil_sockaddr_alloc_ipv4(struct vsf_sysutil_sockaddr** p_sockptr)
{
  vsf_sysutil_sockaddr_alloc(p_sockptr);
  (*p_sockptr)->u.u_sockaddr.sa_family = AF_INET;
}

void
vsf_sysutil_sockaddr_alloc_ipv6(struct vsf_sysutil_sockaddr** p_sockptr)
{
  vsf_sysutil_sockaddr_alloc(p_sockptr);
  (*p_sockptr)->u.u_sockaddr.sa_family = AF_INET6;
}

void
vsf_sysutil_sockaddr_clone(struct vsf_sysutil_sockaddr** p_sockptr,
                           const struct vsf_sysutil_sockaddr* p_src)
{
  struct vsf_sysutil_sockaddr* p_sockaddr = 0;
  vsf_sysutil_sockaddr_alloc(p_sockptr);
  p_sockaddr = *p_sockptr;
  if (p_src->u.u_sockaddr.sa_family == AF_INET)
  {
    p_sockaddr->u.u_sockaddr.sa_family = AF_INET;
    vsf_sysutil_memcpy(&p_sockaddr->u.u_sockaddr_in.sin_addr,
                       &p_src->u.u_sockaddr_in.sin_addr,
                       sizeof(p_sockaddr->u.u_sockaddr_in.sin_addr));
  }
  else if (p_src->u.u_sockaddr.sa_family == AF_INET6)
  {
    p_sockaddr->u.u_sockaddr.sa_family = AF_INET6;
    vsf_sysutil_memcpy(&p_sockaddr->u.u_sockaddr_in6.sin6_addr,
                       &p_src->u.u_sockaddr_in6.sin6_addr,
                       sizeof(p_sockaddr->u.u_sockaddr_in6.sin6_addr));
  }
  else
  {
    die("can only support ipv4 and ipv6 currently");
  }
}

int
vsf_sysutil_sockaddr_addr_equal(const struct vsf_sysutil_sockaddr* p1,
                                const struct vsf_sysutil_sockaddr* p2)
{
  int family1 = p1->u.u_sockaddr.sa_family;
  int family2 = p2->u.u_sockaddr.sa_family;
  if (family1 != family2)
  {
    if (family1 == AF_INET && family2 == AF_INET6)
    {
      const void* p_ipv4_addr = vsf_sysutil_sockaddr_ipv6_v4(p2);
      if (p_ipv4_addr &&
          !vsf_sysutil_memcmp(p_ipv4_addr, &p1->u.u_sockaddr_in.sin_addr,
                              sizeof(p1->u.u_sockaddr_in.sin_addr)))
      {
        return 1;
      }
    }
    else if (family1 == AF_INET6 && family2 == AF_INET)
    {
      const void* p_ipv4_addr = vsf_sysutil_sockaddr_ipv6_v4(p1);
      if (p_ipv4_addr &&
          !vsf_sysutil_memcmp(p_ipv4_addr, &p2->u.u_sockaddr_in.sin_addr,
                              sizeof(p2->u.u_sockaddr_in.sin_addr)))
      {
        return 1;
      }
    }
    return 0;
  }
  if (family1 == AF_INET)
  {
    if (vsf_sysutil_memcmp(&p1->u.u_sockaddr_in.sin_addr,
                           &p2->u.u_sockaddr_in.sin_addr,
                           sizeof(p1->u.u_sockaddr_in.sin_addr)) == 0)
    {
      return 1;
    }
  }
  else if (family1 == AF_INET6)
  {
    if (vsf_sysutil_memcmp(&p1->u.u_sockaddr_in6.sin6_addr,
                           &p2->u.u_sockaddr_in6.sin6_addr,
                           sizeof(p1->u.u_sockaddr_in6.sin6_addr)) == 0)
    {
      return 1;
    }
  }
  return 0;
}

int
vsf_sysutil_sockaddr_is_ipv6(const struct vsf_sysutil_sockaddr* p_sockaddr)
{
  if (p_sockaddr->u.u_sockaddr.sa_family == AF_INET6)
  {
    return 1;
  }
  return 0;
}

void
vsf_sysutil_sockaddr_set_ipv4addr(struct vsf_sysutil_sockaddr* p_sockptr,
                                  const unsigned char* p_raw)
{
  if (p_sockptr->u.u_sockaddr.sa_family == AF_INET)
  {
    vsf_sysutil_memcpy(&p_sockptr->u.u_sockaddr_in.sin_addr, p_raw,
                       sizeof(p_sockptr->u.u_sockaddr_in.sin_addr));
  }
  else if (p_sockptr->u.u_sockaddr.sa_family == AF_INET6)
  {
    static struct vsf_sysutil_sockaddr* s_p_sockaddr;
    vsf_sysutil_sockaddr_alloc_ipv4(&s_p_sockaddr);
    vsf_sysutil_memcpy(&s_p_sockaddr->u.u_sockaddr_in.sin_addr, p_raw,
                       sizeof(&s_p_sockaddr->u.u_sockaddr_in.sin_addr));
    vsf_sysutil_memcpy(&p_sockptr->u.u_sockaddr_in6.sin6_addr,
                       vsf_sysutil_sockaddr_ipv4_v6(s_p_sockaddr),
                       sizeof(p_sockptr->u.u_sockaddr_in6.sin6_addr));
  }
  else
  {
    bug("bad family");
  }
}

void
vsf_sysutil_sockaddr_set_ipv6addr(struct vsf_sysutil_sockaddr* p_sockptr,
                                  const unsigned char* p_raw)
{
  if (p_sockptr->u.u_sockaddr.sa_family == AF_INET6)
  {
    vsf_sysutil_memcpy(&p_sockptr->u.u_sockaddr_in6.sin6_addr, p_raw,
                       sizeof(p_sockptr->u.u_sockaddr_in6.sin6_addr));
  }
  else
  {
    bug("bad family");
  }