fixes #543 Add logging support framework

1 files changed, 284 insertions, 0 deletions

diff --git a/src/core/log.c b/src/core/log.c
new file mode 100644
index 00000000..b560f6c7
--- /dev/null
+++ b/src/core/log.c
@@ -0,0 +1,284 @@
+
+// Copyright 2024 Staysail Systems, Inc. <info@staysail.tech>
+//
+// This software is supplied under the terms of the MIT License, a
+// copy of which should be located in the distribution where this
+// file was obtained (LICENSE.txt).  A copy of the license may also be
+// found online at https://opensource.org/licenses/MIT.
+//
+
+#include "nng/nng.h"
+#include "nng_impl.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#ifdef NNG_PLATFORM_WINDOWS
+#include <io.h>
+#endif
+#ifdef NNG_PLATFORM_POSIX
+#include <syslog.h>
+#include <unistd.h>
+#endif
+#include <time.h>
+
+static nng_log_level    log_level    = NNG_LOG_NOTICE;
+static nng_log_facility log_facility = NNG_LOG_USER;
+static nng_logger       log_logger   = nng_null_logger;
+
+void
+nng_log_set_facility(nng_log_facility facility)
+{
+	log_facility = facility;
+}
+
+void
+nng_log_set_level(nng_log_level level)
+{
+	log_level = level;
+}
+
+void
+nng_log_set_logger(nng_logger logger)
+{
+	if (logger == NULL) {
+		logger = nng_null_logger;
+	}
+	log_logger = logger;
+}
+
+void
+nng_null_logger(nng_log_level level, nng_log_facility facility,
+    const char *msgid, const char *msg)
+{
+	NNI_ARG_UNUSED(level);
+	NNI_ARG_UNUSED(facility);
+	NNI_ARG_UNUSED(msgid);
+	NNI_ARG_UNUSED(msg);
+	return;
+}
+
+void
+nng_stderr_logger(nng_log_level level, nng_log_facility facility,
+    const char *msgid, const char *msg)
+{
+	const char *sgr, *sgr0;
+	// Initial implementation.
+	bool        colors = false;
+	const char *level_str;
+	time_t      now;
+	char        when[64];
+	NNI_ARG_UNUSED(facility);
+
+#ifdef NNG_PLATFORM_WINDOWS
+	// NB: We are blithely assuming the user has a modern console.
+	colors = _isatty(_fileno(stderr));
+#elif defined(NNG_PLATFORM_POSIX)
+	// Only assuming we can use colors (and attributes) if stderr is a tty
+	// and $TERM is reasonable. We assume the terminal supports ECMA-48,
+	// which is true on every reasonable system these days.
+	colors = isatty(fileno(stderr)) && (getenv("TERM") != NULL) &&
+	    (getenv("TERM")[0] != 0);
+#else
+	now    = 0;
+	colors = false;
+#endif
+
+	// Escape hatch to prevent colorizing logs if we have to.  Users on
+	// legacy Windows can set this, or on ancient HP terminals or
+	// something.  Also in the same way that no-color.org proposes.
+	// The reason for both is to allow suppression *only* for NNG.  There
+	// is no good reason to enable it to override the presence of NO_COLOR.
+	if ((getenv("NNG_LOG_NO_COLOR") != NULL) ||
+	    (getenv("NO_COLOR") != NULL)) {
+		colors = false;
+	}
+	now = time(NULL);
+#ifdef NNG_HAVE_LOCALTIME_R
+	struct tm tm;
+	// No timezone offset, not strictly ISO8601 compliant
+	strftime(when, sizeof(when), "%Y-%m-%d %T", localtime_r(&now, &tm));
+#else
+	strftime(when, sizeof(when), "%Y-%m-%d %T", localtime(&now));
+#endif
+
+	switch (level) {
+	case NNG_LOG_ERR:
+		sgr       = "\x1b[31m"; // red
+		sgr0      = "\x1b[0m";
+		level_str = "ERROR";
+		break;
+	case NNG_LOG_WARN:
+		sgr       = "\x1b[33m"; // yellow
+		sgr0      = "\x1b[0m";
+		level_str = "WARN";
+		break;
+	case NNG_LOG_NOTICE:
+		sgr       = "\x1b[1m"; // bold
+		sgr0      = "\x1b[0m";
+		level_str = "NOTICE";
+		break;
+	case NNG_LOG_DEBUG:
+		sgr       = "\x1b[36m"; // cyan
+		sgr0      = "\x1b[0m";
+		level_str = "DEBUG";
+		break;
+	case NNG_LOG_INFO:
+		sgr       = "";
+		sgr0      = "";
+		level_str = "INFO";
+		break;
+	default:
+		sgr       = "";
+		sgr0      = "";
+		level_str = "NONE";
+		break;
+	}
+
+	if (!colors) {
+		sgr  = "";
+		sgr0 = "";
+	}
+
+	(void) fprintf(stderr, "%s[%-6s]: %s: %s%s%s%s\n", sgr, level_str,
+	    when, msgid ? msgid : "", msgid ? ": " : "", msg, sgr0);
+}
+
+void
+nng_system_logger(nng_log_level level, nng_log_facility facility,
+    const char *msgid, const char *msg)
+{
+#ifdef NNG_PLATFORM_POSIX
+	int pri;
+	switch (level) {
+	case NNG_LOG_ERR:
+		pri = LOG_ERR;
+		break;
+	case NNG_LOG_WARN:
+		pri = LOG_WARNING;
+		break;
+	case NNG_LOG_NOTICE:
+		pri = LOG_NOTICE;
+		break;
+	case NNG_LOG_INFO:
+		pri = LOG_INFO;
+		break;
+	case NNG_LOG_DEBUG:
+		pri = LOG_DEBUG;
+		break;
+	default:
+		pri = LOG_INFO;
+		break;
+	}
+	switch (facility) {
+	case NNG_LOG_DAEMON:
+		pri |= LOG_DAEMON;
+		break;
+	case NNG_LOG_USER:
+		pri |= LOG_USER;
+		break;
+	case NNG_LOG_AUTH:
+		pri |= LOG_AUTHPRIV;
+		break;
+	case NNG_LOG_LOCAL0:
+		pri |= LOG_LOCAL0;
+		break;
+	case NNG_LOG_LOCAL1:
+		pri |= LOG_LOCAL1;
+		break;
+	case NNG_LOG_LOCAL2:
+		pri |= LOG_LOCAL2;
+		break;
+	case NNG_LOG_LOCAL3:
+		pri |= LOG_LOCAL3;
+		break;
+	case NNG_LOG_LOCAL4:
+		pri |= LOG_LOCAL4;
+		break;
+	case NNG_LOG_LOCAL5:
+		pri |= LOG_LOCAL5;
+		break;
+	case NNG_LOG_LOCAL6:
+		pri |= LOG_LOCAL6;
+		break;
+	case NNG_LOG_LOCAL7:
+		pri |= LOG_LOCAL7;
+		break;
+	}
+
+	if (msgid) {
+		syslog(pri, "%s: %s", msgid, msg);
+	} else {
+		syslog(pri, "%s", msg);
+	}
+#else
+	// everyone else just goes to stderr for now
+	nng_stderr_logger(level, facility, msgid, msg);
+#endif
+}
+
+static void
+nni_vlog(nng_log_level level, nng_log_facility facility, const char *msgid,
+    const char *msg, va_list ap)
+{
+	// nobody allowed to log at LOG_EMERG or using LOG_KERN
+	if (level > log_level || log_level == 0 || facility == 0) {
+		return;
+	}
+	char formatted[512];
+	vsnprintf(formatted, sizeof(formatted), msg, ap);
+	log_logger(level, facility, msgid, formatted);
+}
+
+void
+nng_log_debug(const char *msgid, const char *msg, ...)
+{
+	va_list ap;
+	va_start(ap, msg);
+	nni_vlog(NNG_LOG_DEBUG, log_facility, msgid, msg, ap);
+	va_end(ap);
+}
+
+void
+nng_log_info(const char *msgid, const char *msg, ...)
+{
+	va_list ap;
+	va_start(ap, msg);
+	nni_vlog(NNG_LOG_INFO, log_facility, msgid, msg, ap);
+	va_end(ap);
+}
+
+void
+nng_log_notice(const char *msgid, const char *msg, ...)
+{
+	va_list ap;
+	va_start(ap, msg);
+	nni_vlog(NNG_LOG_NOTICE, log_facility, msgid, msg, ap);
+	va_end(ap);
+}
+
+void
+nng_log_warn(const char *msgid, const char *msg, ...)
+{
+	va_list ap;
+	va_start(ap, msg);
+	nni_vlog(NNG_LOG_WARN, log_facility, msgid, msg, ap);
+	va_end(ap);
+}
+
+void
+nng_log_err(const char *msgid, const char *msg, ...)
+{
+	va_list ap;
+	va_start(ap, msg);
+	nni_vlog(NNG_LOG_ERR, log_facility, msgid, msg, ap);
+	va_end(ap);
+}
+
+void
+nng_log_auth(nng_log_level level, const char *msgid, const char *msg, ...)
+{
+	va_list ap;
+	va_start(ap, msg);
+	nni_vlog(level, NNG_LOG_AUTH, msgid, msg, ap);
+	va_end(ap);
+}