From da152331cf2e8537bc3651e10eb8b72d751721c3 Mon Sep 17 00:00:00 2001 From: Stefano Brivio Date: Sat, 24 Sep 2022 09:53:15 +0200 Subject: Move logging functions to a new file, log.c Logging to file is going to add some further complexity that we don't want to squeeze into util.c. Signed-off-by: Stefano Brivio Reviewed-by: David Gibson --- log.c | 143 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 143 insertions(+) create mode 100644 log.c (limited to 'log.c') diff --git a/log.c b/log.c new file mode 100644 index 0000000..54a7cbb --- /dev/null +++ b/log.c @@ -0,0 +1,143 @@ +// SPDX-License-Identifier: AGPL-3.0-or-later + +/* PASST - Plug A Simple Socket Transport + * for qemu/UNIX domain socket mode + * + * PASTA - Pack A Subtle Tap Abstraction + * for network namespace/tap device mode + * + * log.c - Logging functions + * + * Copyright (c) 2020-2022 Red Hat GmbH + * Author: Stefano Brivio + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "log.h" + +/* For __openlog() and __setlogmask() wrappers, and passt_vsyslog() */ +static int log_mask; +static int log_sock = -1; +static char log_ident[BUFSIZ]; +static int log_opt; +static time_t log_debug_start; +int log_trace; + +#define logfn(name, level) \ +void name(const char *format, ...) { \ + struct timespec tp; \ + va_list args; \ + \ + if (setlogmask(0) & LOG_MASK(LOG_DEBUG)) { \ + clock_gettime(CLOCK_REALTIME, &tp); \ + fprintf(stderr, "%li.%04li: ", \ + tp.tv_sec - log_debug_start, \ + tp.tv_nsec / (100L * 1000)); \ + } else { \ + va_start(args, format); \ + passt_vsyslog(level, format, args); \ + va_end(args); \ + } \ + \ + if (setlogmask(0) & LOG_MASK(LOG_DEBUG) || \ + setlogmask(0) == LOG_MASK(LOG_EMERG)) { \ + va_start(args, format); \ + (void)vfprintf(stderr, format, args); \ + va_end(args); \ + if (format[strlen(format)] != '\n') \ + fprintf(stderr, "\n"); \ + } \ +} + +logfn(err, LOG_ERR) +logfn(warn, LOG_WARNING) +logfn(info, LOG_INFO) +logfn(debug, LOG_DEBUG) + +void trace_init(int enable) +{ + log_trace = enable; +} + +/** + * __openlog() - Non-optional openlog() wrapper, to allow custom vsyslog() + * @ident: openlog() identity (program name) + * @option: openlog() options + * @facility: openlog() facility (LOG_DAEMON) + */ +void __openlog(const char *ident, int option, int facility) +{ + struct timespec tp; + + clock_gettime(CLOCK_REALTIME, &tp); + log_debug_start = tp.tv_sec; + + if (log_sock < 0) { + struct sockaddr_un a = { .sun_family = AF_UNIX, }; + + log_sock = socket(AF_UNIX, SOCK_DGRAM | SOCK_CLOEXEC, 0); + if (log_sock < 0) + return; + + strncpy(a.sun_path, _PATH_LOG, sizeof(a.sun_path)); + if (connect(log_sock, (const struct sockaddr *)&a, sizeof(a))) { + close(log_sock); + log_sock = -1; + return; + } + } + + log_mask |= facility; + strncpy(log_ident, ident, sizeof(log_ident) - 1); + log_opt = option; + + openlog(ident, option, facility); +} + +/** + * __setlogmask() - setlogmask() wrapper, to allow custom vsyslog() + * @mask: Same as setlogmask() mask + */ +void __setlogmask(int mask) +{ + log_mask = mask; + setlogmask(mask); +} + +/** + * passt_vsyslog() - vsyslog() implementation not using heap memory + * @pri: Facility and level map, same as priority for vsyslog() + * @format: Same as vsyslog() format + * @ap: Same as vsyslog() ap + */ +void passt_vsyslog(int pri, const char *format, va_list ap) +{ + char buf[BUFSIZ]; + int n; + + if (!(LOG_MASK(LOG_PRI(pri)) & log_mask)) + return; + + /* Send without name and timestamp, the system logger should add them */ + n = snprintf(buf, BUFSIZ, "<%i> ", pri); + + n += vsnprintf(buf + n, BUFSIZ - n, format, ap); + + if (format[strlen(format)] != '\n') + n += snprintf(buf + n, BUFSIZ - n, "\n"); + + if (log_opt & LOG_PERROR) + fprintf(stderr, "%s", buf + sizeof("<0>")); + + if (send(log_sock, buf, n, 0) != n) + fprintf(stderr, "Failed to send %i bytes to syslog\n", n); +} -- cgit v1.2.3