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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-09 12:48:01 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-09 12:48:01 +0000 |
commit | b2d2d555a704148968cb7e566735a2a1b1a2f189 (patch) | |
tree | 18549ff498338f40ecf7aa327620abf4c1c3ee43 /nameserv_async.c | |
parent | Initial commit. (diff) | |
download | chrony-b2d2d555a704148968cb7e566735a2a1b1a2f189.tar.xz chrony-b2d2d555a704148968cb7e566735a2a1b1a2f189.zip |
Adding upstream version 4.5.upstream/4.5upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | nameserv_async.c | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/nameserv_async.c b/nameserv_async.c new file mode 100644 index 0000000..118443c --- /dev/null +++ b/nameserv_async.c @@ -0,0 +1,130 @@ +/* + chronyd/chronyc - Programs for keeping computer clocks accurate. + + ********************************************************************** + * Copyright (C) Miroslav Lichvar 2014 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program 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 + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + ********************************************************************** + + ======================================================================= + + Functions to asynchronously convert name to IP address + + */ + +#include "config.h" +#include "sysincl.h" + +#include "nameserv_async.h" +#include "logging.h" +#include "memory.h" +#include "privops.h" +#include "sched.h" +#include "util.h" + +#ifdef USE_PTHREAD_ASYNCDNS +#include <pthread.h> + +/* ================================================== */ + +struct DNS_Async_Instance { + const char *name; + DNS_Status status; + IPAddr addresses[DNS_MAX_ADDRESSES]; + DNS_NameResolveHandler handler; + void *arg; + + pthread_t thread; + int pipe[2]; +}; + +static pthread_mutex_t privops_lock = PTHREAD_MUTEX_INITIALIZER; + +/* ================================================== */ + +static void * +start_resolving(void *anything) +{ + struct DNS_Async_Instance *inst = (struct DNS_Async_Instance *)anything; + + pthread_mutex_lock(&privops_lock); + inst->status = PRV_Name2IPAddress(inst->name, inst->addresses, DNS_MAX_ADDRESSES); + pthread_mutex_unlock(&privops_lock); + + /* Notify the main thread that the result is ready */ + if (write(inst->pipe[1], "", 1) < 0) + ; + + return NULL; +} + +/* ================================================== */ + +static void +end_resolving(int fd, int event, void *anything) +{ + struct DNS_Async_Instance *inst = (struct DNS_Async_Instance *)anything; + int i; + + if (pthread_join(inst->thread, NULL)) { + LOG_FATAL("pthread_join() failed"); + } + + SCH_RemoveFileHandler(inst->pipe[0]); + close(inst->pipe[0]); + close(inst->pipe[1]); + + for (i = 0; inst->status == DNS_Success && i < DNS_MAX_ADDRESSES && + inst->addresses[i].family != IPADDR_UNSPEC; i++) + ; + + (inst->handler)(inst->status, i, inst->addresses, inst->arg); + + Free(inst); +} + +/* ================================================== */ + +void +DNS_Name2IPAddressAsync(const char *name, DNS_NameResolveHandler handler, void *anything) +{ + struct DNS_Async_Instance *inst; + + inst = MallocNew(struct DNS_Async_Instance); + inst->name = name; + inst->handler = handler; + inst->arg = anything; + inst->status = DNS_Failure; + + if (pipe(inst->pipe)) { + LOG_FATAL("pipe() failed"); + } + + UTI_FdSetCloexec(inst->pipe[0]); + UTI_FdSetCloexec(inst->pipe[1]); + + if (pthread_create(&inst->thread, NULL, start_resolving, inst)) { + LOG_FATAL("pthread_create() failed"); + } + + SCH_AddFileHandler(inst->pipe[0], SCH_FILE_INPUT, end_resolving, inst); +} + +/* ================================================== */ + +#else +#error +#endif |