treewide: consolidate platform specific code in platform.c

Get rid of most __APPLE__ guards by introducing a central platform.c unit
providing drop-in replacements for missing APIs.

Also move system signal definitions into the new platform file to be able
to share them with the upcoming debug library.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

1 files changed, 242 insertions, 0 deletions

diff --git a/platform.c b/platform.c
new file mode 100644
index 0000000..63a79d4
--- /dev/null
+++ b/platform.c
@@ -0,0 +1,242 @@
+/*
+ * Copyright (C) 2023 Jo-Philipp Wich <jo@mein.io>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <errno.h>
+
+#include "ucode/platform.h"
+
+const char *uc_system_signal_names[UC_SYSTEM_SIGNAL_COUNT] = {
+#if defined(SIGINT)
+	[SIGINT] = "INT",
+#endif
+#if defined(SIGILL)
+	[SIGILL] = "ILL",
+#endif
+#if defined(SIGABRT)
+	[SIGABRT] = "ABRT",
+#endif
+#if defined(SIGFPE)
+	[SIGFPE] = "FPE",
+#endif
+#if defined(SIGSEGV)
+	[SIGSEGV] = "SEGV",
+#endif
+#if defined(SIGTERM)
+	[SIGTERM] = "TERM",
+#endif
+#if defined(SIGHUP)
+	[SIGHUP] = "HUP",
+#endif
+#if defined(SIGQUIT)
+	[SIGQUIT] = "QUIT",
+#endif
+#if defined(SIGTRAP)
+	[SIGTRAP] = "TRAP",
+#endif
+#if defined(SIGKILL)
+	[SIGKILL] = "KILL",
+#endif
+#if defined(SIGPIPE)
+	[SIGPIPE] = "PIPE",
+#endif
+#if defined(SIGALRM)
+	[SIGALRM] = "ALRM",
+#endif
+#if defined(SIGSTKFLT)
+	[SIGSTKFLT] = "STKFLT",
+#endif
+#if defined(SIGPWR)
+	[SIGPWR] = "PWR",
+#endif
+#if defined(SIGBUS)
+	[SIGBUS] = "BUS",
+#endif
+#if defined(SIGSYS)
+	[SIGSYS] = "SYS",
+#endif
+#if defined(SIGURG)
+	[SIGURG] = "URG",
+#endif
+#if defined(SIGSTOP)
+	[SIGSTOP] = "STOP",
+#endif
+#if defined(SIGTSTP)
+	[SIGTSTP] = "TSTP",
+#endif
+#if defined(SIGCONT)
+	[SIGCONT] = "CONT",
+#endif
+#if defined(SIGCHLD)
+	[SIGCHLD] = "CHLD",
+#endif
+#if defined(SIGTTIN)
+	[SIGTTIN] = "TTIN",
+#endif
+#if defined(SIGTTOU)
+	[SIGTTOU] = "TTOU",
+#endif
+#if defined(SIGPOLL)
+	[SIGPOLL] = "POLL",
+#endif
+#if defined(SIGXFSZ)
+	[SIGXFSZ] = "XFSZ",
+#endif
+#if defined(SIGXCPU)
+	[SIGXCPU] = "XCPU",
+#endif
+#if defined(SIGVTALRM)
+	[SIGVTALRM] = "VTALRM",
+#endif
+#if defined(SIGPROF)
+	[SIGPROF] = "PROF",
+#endif
+#if defined(SIGUSR1)
+	[SIGUSR1] = "USR1",
+#endif
+#if defined(SIGUSR2)
+	[SIGUSR2] = "USR2",
+#endif
+};
+
+
+#ifdef __APPLE__
+int
+pipe2(int pipefd[2], int flags)
+{
+	if (pipe(pipefd) != 0)
+		return -1;
+
+	if (flags & O_CLOEXEC) {
+		if (fcntl(pipefd[0], F_SETFD, FD_CLOEXEC) != 0 ||
+		    fcntl(pipefd[1], F_SETFD, FD_CLOEXEC) != 0) {
+			close(pipefd[0]);
+			close(pipefd[1]);
+
+			return -1;
+		}
+
+		flags &= ~O_CLOEXEC;
+	}
+
+	if (fcntl(pipefd[0], F_SETFL, flags) != 0 ||
+	    fcntl(pipefd[1], F_SETFL, flags) != 0) {
+		close(pipefd[0]);
+		close(pipefd[1]);
+
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * sigtimedwait() implementation based on
+ * https://comp.unix.programmer.narkive.com/rEDH0sPT/sigtimedwait-implementation
+ * and
+ * https://github.com/wahern/lunix/blob/master/src/unix.c
+ */
+static void
+sigtimedwait_consume_signal(int signo)
+{
+}
+
+int
+sigtimedwait(const sigset_t *set, siginfo_t *info, const struct timespec *timeout)
+{
+	struct timespec elapsed = { 0, 0 }, sleep, rem;
+	sigset_t pending, unblock, omask;
+	struct sigaction sa, osa;
+	int signo;
+	bool lt;
+
+	while (true) {
+		sigemptyset(&pending);
+		sigpending(&pending);
+
+		for (signo = 1; signo < NSIG; signo++) {
+			if (!sigismember(set, signo) || !sigismember(&pending, signo))
+				continue;
+
+			sa.sa_handler = sigtimedwait_consume_signal;
+			sa.sa_flags = 0;
+			sigfillset(&sa.sa_mask);
+
+			sigaction(signo, &sa, &osa);
+
+			sigemptyset(&unblock);
+			sigaddset(&unblock, signo);
+			sigprocmask(SIG_UNBLOCK, &unblock, &omask);
+			sigprocmask(SIG_SETMASK, &omask, NULL);
+
+			sigaction(signo, &osa, NULL);
+
+			if (info) {
+				memset(info, 0, sizeof(*info));
+				info->si_signo = signo;
+			}
+
+			return signo;
+		}
+
+		sleep.tv_sec = 0;
+		sleep.tv_nsec = 200000000L; /* 2/10th second */
+		rem = sleep;
+
+		if (nanosleep(&sleep, &rem) == 0) {
+			elapsed.tv_sec += sleep.tv_sec;
+			elapsed.tv_nsec += sleep.tv_nsec;
+
+			if (elapsed.tv_nsec > 1000000000) {
+				elapsed.tv_sec++;
+				elapsed.tv_nsec -= 1000000000;
+			}
+		}
+		else if (errno == EINTR) {
+			sleep.tv_sec -= rem.tv_sec;
+			sleep.tv_nsec -= rem.tv_nsec;
+
+			if (sleep.tv_nsec < 0) {
+				sleep.tv_sec--;
+				sleep.tv_nsec += 1000000000;
+			}
+
+			elapsed.tv_sec += sleep.tv_sec;
+			elapsed.tv_nsec += sleep.tv_nsec;
+
+			if (elapsed.tv_nsec > 1000000000) {
+				elapsed.tv_sec++;
+				elapsed.tv_nsec -= 1000000000;
+			}
+		}
+		else {
+			return errno;
+		}
+
+		lt = timeout
+			? ((elapsed.tv_sec == timeout->tv_sec)
+				? (elapsed.tv_nsec < timeout->tv_nsec)
+				: (elapsed.tv_sec < timeout->tv_sec))
+			: true;
+
+		if (!lt)
+			break;
+	}
+
+	errno = EAGAIN;
+
+	return -1;
+}
+#endif