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-rw-r--r--external/unbound/util/locks.c264
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diff --git a/external/unbound/util/locks.c b/external/unbound/util/locks.c
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+/**
+ * util/locks.c - unbound locking primitives
+ *
+ * Copyright (c) 2007, NLnet Labs. All rights reserved.
+ *
+ * This software is open source.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of the NLNET LABS nor the names of its contributors may
+ * be used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/**
+ * \file
+ * Implementation of locking and threading support.
+ * A place for locking debug code since most locking functions are macros.
+ */
+
+#include "config.h"
+#include "util/locks.h"
+#include <signal.h>
+#ifdef HAVE_SYS_WAIT_H
+#include <sys/wait.h>
+#endif
+
+/** block all signals, masks them away. */
+void
+ub_thread_blocksigs(void)
+{
+#if defined(HAVE_PTHREAD) || defined(HAVE_SOLARIS_THREADS) || defined(HAVE_SIGPROCMASK)
+# if defined(HAVE_PTHREAD) || defined(HAVE_SOLARIS_THREADS)
+ int err;
+# endif
+ sigset_t sigset;
+ sigfillset(&sigset);
+#ifdef HAVE_PTHREAD
+ if((err=pthread_sigmask(SIG_SETMASK, &sigset, NULL)))
+ fatal_exit("pthread_sigmask: %s", strerror(err));
+#else
+# ifdef HAVE_SOLARIS_THREADS
+ if((err=thr_sigsetmask(SIG_SETMASK, &sigset, NULL)))
+ fatal_exit("thr_sigsetmask: %s", strerror(err));
+# else
+ /* have nothing, do single process signal mask */
+ if(sigprocmask(SIG_SETMASK, &sigset, NULL))
+ fatal_exit("sigprocmask: %s", strerror(errno));
+# endif /* HAVE_SOLARIS_THREADS */
+#endif /* HAVE_PTHREAD */
+#endif /* have signal stuff */
+}
+
+/** unblock one signal, so we can catch it */
+void ub_thread_sig_unblock(int sig)
+{
+#if defined(HAVE_PTHREAD) || defined(HAVE_SOLARIS_THREADS) || defined(HAVE_SIGPROCMASK)
+# if defined(HAVE_PTHREAD) || defined(HAVE_SOLARIS_THREADS)
+ int err;
+# endif
+ sigset_t sigset;
+ sigemptyset(&sigset);
+ sigaddset(&sigset, sig);
+#ifdef HAVE_PTHREAD
+ if((err=pthread_sigmask(SIG_UNBLOCK, &sigset, NULL)))
+ fatal_exit("pthread_sigmask: %s", strerror(err));
+#else
+# ifdef HAVE_SOLARIS_THREADS
+ if((err=thr_sigsetmask(SIG_UNBLOCK, &sigset, NULL)))
+ fatal_exit("thr_sigsetmask: %s", strerror(err));
+# else
+ /* have nothing, do single thread case */
+ if(sigprocmask(SIG_UNBLOCK, &sigset, NULL))
+ fatal_exit("sigprocmask: %s", strerror(errno));
+# endif /* HAVE_SOLARIS_THREADS */
+#endif /* HAVE_PTHREAD */
+#else
+ (void)sig;
+#endif /* have signal stuff */
+}
+
+#if !defined(HAVE_PTHREAD) && !defined(HAVE_SOLARIS_THREADS) && !defined(HAVE_WINDOWS_THREADS)
+/**
+ * No threading available: fork a new process.
+ * This means no shared data structure, and no locking.
+ * Only the main thread ever returns. Exits on errors.
+ * @param thr: the location where to store the thread-id.
+ * @param func: function body of the thread. Return value of func is lost.
+ * @param arg: user argument to func.
+ */
+void
+ub_thr_fork_create(ub_thread_t* thr, void* (*func)(void*), void* arg)
+{
+ pid_t pid = fork();
+ switch(pid) {
+ default: /* main */
+ *thr = (ub_thread_t)pid;
+ return;
+ case 0: /* child */
+ *thr = (ub_thread_t)getpid();
+ (void)(*func)(arg);
+ exit(0);
+ case -1: /* error */
+ fatal_exit("could not fork: %s", strerror(errno));
+ }
+}
+
+/**
+ * There is no threading. Wait for a process to terminate.
+ * Note that ub_thread_t is defined as pid_t.
+ * @param thread: the process id to wait for.
+ */
+void ub_thr_fork_wait(ub_thread_t thread)
+{
+ int status = 0;
+ if(waitpid((pid_t)thread, &status, 0) == -1)
+ log_err("waitpid(%d): %s", (int)thread, strerror(errno));
+ if(status != 0)
+ log_warn("process %d abnormal exit with status %d",
+ (int)thread, status);
+}
+#endif /* !defined(HAVE_PTHREAD) && !defined(HAVE_SOLARIS_THREADS) && !defined(HAVE_WINDOWS_THREADS) */
+
+#ifdef HAVE_SOLARIS_THREADS
+void* ub_thread_key_get(ub_thread_key_t key)
+{
+ void* ret=NULL;
+ LOCKRET(thr_getspecific(key, &ret));
+ return ret;
+}
+#endif
+
+#ifdef HAVE_WINDOWS_THREADS
+/** log a windows GetLastError message */
+static void log_win_err(const char* str, DWORD err)
+{
+ LPTSTR buf;
+ if(FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM |
+ FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_ALLOCATE_BUFFER,
+ NULL, err, 0, (LPTSTR)&buf, 0, NULL) == 0) {
+ /* could not format error message */
+ log_err("%s, GetLastError=%d", str, (int)err);
+ return;
+ }
+ log_err("%s, (err=%d): %s", str, (int)err, buf);
+ LocalFree(buf);
+}
+
+void lock_basic_init(lock_basic_t* lock)
+{
+ /* implement own lock, because windows HANDLE as Mutex usage
+ * uses too many handles and would bog down the whole system. */
+ (void)InterlockedExchange(lock, 0);
+}
+
+void lock_basic_destroy(lock_basic_t* lock)
+{
+ (void)InterlockedExchange(lock, 0);
+}
+
+void lock_basic_lock(lock_basic_t* lock)
+{
+ LONG wait = 1; /* wait 1 msec at first */
+
+ while(InterlockedExchange(lock, 1)) {
+ /* if the old value was 1 then if was already locked */
+ Sleep(wait); /* wait with sleep */
+ wait *= 2; /* exponential backoff for waiting */
+ }
+ /* the old value was 0, but we inserted 1, we locked it! */
+}
+
+void lock_basic_unlock(lock_basic_t* lock)
+{
+ /* unlock it by inserting the value of 0. xchg for cache coherency. */
+ (void)InterlockedExchange(lock, 0);
+}
+
+void ub_thread_key_create(ub_thread_key_t* key, void* f)
+{
+ *key = TlsAlloc();
+ if(*key == TLS_OUT_OF_INDEXES) {
+ *key = 0;
+ log_win_err("TlsAlloc Failed(OUT_OF_INDEXES)", GetLastError());
+ }
+ else ub_thread_key_set(*key, f);
+}
+
+void ub_thread_key_set(ub_thread_key_t key, void* v)
+{
+ if(!TlsSetValue(key, v)) {
+ log_win_err("TlsSetValue failed", GetLastError());
+ }
+}
+
+void* ub_thread_key_get(ub_thread_key_t key)
+{
+ void* ret = (void*)TlsGetValue(key);
+ if(ret == NULL && GetLastError() != ERROR_SUCCESS) {
+ log_win_err("TlsGetValue failed", GetLastError());
+ }
+ return ret;
+}
+
+void ub_thread_create(ub_thread_t* thr, void* (*func)(void*), void* arg)
+{
+#ifndef HAVE__BEGINTHREADEX
+ *thr = CreateThread(NULL, /* default security (no inherit handle) */
+ 0, /* default stack size */
+ (LPTHREAD_START_ROUTINE)func, arg,
+ 0, /* default flags, run immediately */
+ NULL); /* do not store thread identifier anywhere */
+#else
+ /* the begintheadex routine setups for the C lib; aligns stack */
+ *thr=(ub_thread_t)_beginthreadex(NULL, 0, (void*)func, arg, 0, NULL);
+#endif
+ if(*thr == NULL) {
+ log_win_err("CreateThread failed", GetLastError());
+ fatal_exit("thread create failed");
+ }
+}
+
+ub_thread_t ub_thread_self(void)
+{
+ return GetCurrentThread();
+}
+
+void ub_thread_join(ub_thread_t thr)
+{
+ DWORD ret = WaitForSingleObject(thr, INFINITE);
+ if(ret == WAIT_FAILED) {
+ log_win_err("WaitForSingleObject(Thread):WAIT_FAILED",
+ GetLastError());
+ } else if(ret == WAIT_TIMEOUT) {
+ log_win_err("WaitForSingleObject(Thread):WAIT_TIMEOUT",
+ GetLastError());
+ }
+ /* and close the handle to the thread */
+ if(!CloseHandle(thr)) {
+ log_win_err("CloseHandle(Thread) failed", GetLastError());
+ }
+}
+#endif /* HAVE_WINDOWS_THREADS */