Add project files.

libsql/src/Tellwait.cpp

@@ -0,0 +1,87 @@
+#ifndef __WIN32__
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+
+static volatile sig_atomic_t    sigflag;
+
+/* set nonzero by signal handler */
+static sigset_t                 newmask, oldmask, zeromask;
+
+static void sig_usr(int signo)  /* one signal handler for SIGUSR1 and SIGUSR2 */
+{
+	sigflag = 1;
+	return;
+}
+
+void TELL_WAIT()
+{
+	if (signal(SIGUSR1, sig_usr) == SIG_ERR)
+	{
+		fprintf(stderr, "signal(SIGINT) error\n");
+		exit(1);
+	}
+
+	if (signal(SIGUSR2, sig_usr) == SIG_ERR)
+	{
+		fprintf(stderr, "signal(SIGQUIT) error\n");
+		exit(1);
+	}
+
+	sigemptyset(&zeromask);
+
+	sigemptyset(&newmask);
+	sigaddset(&newmask, SIGUSR1);
+	sigaddset(&newmask, SIGUSR2);
+
+	/* block SIGUSR1 and SIGUSR2, and save current signal mask */
+	if (sigprocmask(SIG_BLOCK, &newmask, &oldmask) < 0)
+	{
+		fprintf(stderr, "SIG_BLOCK error\n");
+		exit(1);
+	}
+}
+
+void TELL_PARENT(pid_t pid)
+{
+	kill(pid, SIGUSR2);         /* tell parent we're done */
+}
+
+void WAIT_PARENT(void)
+{
+	while (sigflag == 0)
+		sigsuspend(&zeromask);  /* and wait for parent */
+
+	sigflag = 0;
+
+	/* reset signal mask to original value */
+	if (sigprocmask(SIG_SETMASK, &oldmask, NULL) < 0)
+	{
+		fprintf(stderr, "SIG_SETMASK error\n");
+		exit(1);
+	}
+}
+
+void TELL_CHILD(pid_t pid)
+{
+	kill(pid, SIGUSR1);                 /* tell child we're done */
+}
+
+void WAIT_CHILD(void)
+{
+	while (sigflag == 0)
+		sigsuspend(&zeromask);  /* and wait for child */
+
+	sigflag = 0;
+
+	/* reset signal mask to original value */
+	if (sigprocmask(SIG_SETMASK, &oldmask, NULL) < 0)
+	{
+		fprintf(stderr, "SIG_SETMASK error\n");
+		exit(1);
+	}
+}
+
+#endif
+