1 files changed, 387 insertions, 0 deletions
diff --git a/logging.c b/logging.c
new file mode 100644
index 0000000..ec9ec53
--- /dev/null
+++ b/logging.c
@@ -0,0 +1,387 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Richard P. Curnow  1997-2003
+ * Copyright (C) Miroslav Lichvar  2011-2014, 2018-2020
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Module to handle logging of diagnostic information
+  */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include <syslog.h>
+
+#include "conf.h"
+#include "logging.h"
+#include "memory.h"
+#include "util.h"
+
+/* This is used by DEBUG_LOG macro */
+LOG_Severity log_min_severity = LOGS_INFO;
+
+/* Current logging contexts */
+static LOG_Context log_contexts;
+
+/* ================================================== */
+/* Flag indicating we have initialised */
+static int initialised = 0;
+
+static FILE *file_log = NULL;
+static int system_log = 0;
+
+static int parent_fd = 0;
+
+struct LogFile {
+  const char *name;
+  const char *banner;
+  FILE *file;
+  unsigned long writes;
+};
+
+static int n_filelogs = 0;
+
+/* Increase this when adding a new logfile */
+#define MAX_FILELOGS 6
+
+static struct LogFile logfiles[MAX_FILELOGS];
+
+/* Global prefix for debug messages */
+static char *debug_prefix;
+
+/* ================================================== */
+/* Init function */
+
+void
+LOG_Initialise(void)
+{
+  debug_prefix = Strdup("");
+  log_contexts = 0;
+
+  initialised = 1;
+  LOG_OpenFileLog(NULL);
+}
+
+/* ================================================== */
+/* Fini function */
+
+void
+LOG_Finalise(void)
+{
+  if (system_log)
+    closelog();
+
+  if (file_log)
+    fclose(file_log);
+
+  LOG_CycleLogFiles();
+
+  Free(debug_prefix);
+
+  initialised = 0;
+}
+
+/* ================================================== */
+
+static void log_message(int fatal, LOG_Severity severity, const char *message)
+{
+  if (system_log) {
+    int priority;
+    switch (severity) {
+      case LOGS_DEBUG:
+        priority = LOG_DEBUG;
+        break;
+      case LOGS_INFO:
+        priority = LOG_INFO;
+        break;
+      case LOGS_WARN:
+        priority = LOG_WARNING;
+        break;
+      case LOGS_ERR:
+        priority = LOG_ERR;
+        break;
+      case LOGS_FATAL:
+        priority = LOG_CRIT;
+        break;
+      default:
+        assert(0);
+    }
+    syslog(priority, fatal ? "Fatal error : %s" : "%s", message);
+  } else if (file_log) {
+    fprintf(file_log, fatal ? "Fatal error : %s\n" : "%s\n", message);
+  }
+}
+
+/* ================================================== */
+
+void LOG_Message(LOG_Severity severity,
+#if DEBUG > 0
+                 int line_number, const char *filename, const char *function_name,
+#endif
+                 const char *format, ...)
+{
+  char buf[2048];
+  va_list other_args;
+  time_t t;
+  struct tm *tm;
+
+  assert(initialised);
+  severity = CLAMP(LOGS_DEBUG, severity, LOGS_FATAL);
+
+  if (!system_log && file_log && severity >= log_min_severity) {
+    /* Don't clutter up syslog with timestamps and internal debugging info */
+    time(&t);
+    tm = gmtime(&t);
+    if (tm) {
+      strftime(buf, sizeof (buf), "%Y-%m-%dT%H:%M:%SZ", tm);
+      fprintf(file_log, "%s ", buf);
+    }
+#if DEBUG > 0
+    if (log_min_severity <= LOGS_DEBUG) {
+      /* Log severity to character mapping (debug, info, warn, err, fatal) */
+      const char severity_chars[LOGS_FATAL - LOGS_DEBUG + 1] = {'D', 'I', 'W', 'E', 'F'};
+
+      fprintf(file_log, "%c:%s%s:%d:(%s) ", severity_chars[severity - LOGS_DEBUG],
+              debug_prefix, filename, line_number, function_name);
+    }
+#endif
+  }
+
+  va_start(other_args, format);
+  vsnprintf(buf, sizeof(buf), format, other_args);
+  va_end(other_args);
+
+  switch (severity) {
+    case LOGS_DEBUG:
+    case LOGS_INFO:
+    case LOGS_WARN:
+    case LOGS_ERR:
+      if (severity >= log_min_severity)
+        log_message(0, severity, buf);
+      break;
+    case LOGS_FATAL:
+      if (severity >= log_min_severity)
+        log_message(1, severity, buf);
+
+      /* Send the message also to the foreground process if it is
+         still running, or stderr if it is still open */
+      if (parent_fd > 0) {
+        if (write(parent_fd, buf, strlen(buf) + 1) < 0)
+          ; /* Not much we can do here */
+      } else if (system_log && parent_fd == 0) {
+        system_log = 0;
+        log_message(1, severity, buf);
+      }
+      exit(1);
+      break;
+    default:
+      assert(0);
+  }
+}
+
+/* ================================================== */
+
+void
+LOG_OpenFileLog(const char *log_file)
+{
+  FILE *f;
+
+  if (log_file) {
+    f = UTI_OpenFile(NULL, log_file, NULL, 'A', 0640);
+  } else {
+    f = stderr;
+  }
+
+  /* Enable line buffering */
+  setvbuf(f, NULL, _IOLBF, BUFSIZ);
+
+  if (file_log && file_log != stderr)
+    fclose(file_log);
+
+  file_log = f;
+}
+
+
+/* ================================================== */
+
+void
+LOG_OpenSystemLog(void)
+{
+  system_log = 1;
+  openlog("chronyd", LOG_PID, LOG_DAEMON);
+}
+
+/* ================================================== */
+
+void LOG_SetMinSeverity(LOG_Severity severity)
+{
+  /* Don't print any debug messages in a non-debug build */
+  log_min_severity = CLAMP(DEBUG > 0 ? LOGS_DEBUG : LOGS_INFO, severity, LOGS_FATAL);
+}
+
+/* ================================================== */
+
+LOG_Severity
+LOG_GetMinSeverity(void)
+{
+  return log_min_severity;
+}
+
+/* ================================================== */
+
+void
+LOG_SetContext(LOG_Context context)
+{
+  log_contexts |= context;
+}
+
+/* ================================================== */
+
+void
+LOG_UnsetContext(LOG_Context context)
+{
+  log_contexts &= ~context;
+}
+
+/* ================================================== */
+
+LOG_Severity
+LOG_GetContextSeverity(LOG_Context contexts)
+{
+  return log_contexts & contexts ? LOGS_INFO : LOGS_DEBUG;
+}
+
+/* ================================================== */
+
+void
+LOG_SetDebugPrefix(const char *prefix)
+{
+  Free(debug_prefix);
+  debug_prefix = Strdup(prefix);
+}
+
+/* ================================================== */
+
+void
+LOG_SetParentFd(int fd)
+{
+  parent_fd = fd;
+  if (file_log == stderr)
+    file_log = NULL;
+}
+
+/* ================================================== */
+
+void
+LOG_CloseParentFd()
+{
+  if (parent_fd > 0)
+    close(parent_fd);
+  parent_fd = -1;
+}
+
+/* ================================================== */
+
+LOG_FileID
+LOG_FileOpen(const char *name, const char *banner)
+{
+  if (n_filelogs >= MAX_FILELOGS) {
+    assert(0);
+    return -1;
+  }
+
+  logfiles[n_filelogs].name = name;
+  logfiles[n_filelogs].banner = banner;
+  logfiles[n_filelogs].file = NULL;
+  logfiles[n_filelogs].writes = 0;
+
+  return n_filelogs++;
+}
+
+/* ================================================== */
+
+void
+LOG_FileWrite(LOG_FileID id, const char *format, ...)
+{
+  va_list other_args;
+  int banner;
+
+  if (id < 0 || id >= n_filelogs || !logfiles[id].name)
+    return;
+
+  if (!logfiles[id].file) {
+    char *logdir = CNF_GetLogDir();
+
+    if (!logdir) {
+      LOG(LOGS_WARN, "logdir not specified");
+      logfiles[id].name = NULL;
+      return;
+    }
+
+    logfiles[id].file = UTI_OpenFile(logdir, logfiles[id].name, ".log", 'a', 0644);
+    if (!logfiles[id].file) {
+      /* Disable the log */
+      logfiles[id].name = NULL;
+      return;
+    }
+  }
+
+  banner = CNF_GetLogBanner();
+  if (banner && logfiles[id].writes++ % banner == 0) {
+    char bannerline[256];
+    int i, bannerlen;
+
+    bannerlen = MIN(strlen(logfiles[id].banner), sizeof (bannerline) - 1);
+
+    for (i = 0; i < bannerlen; i++)
+      bannerline[i] = '=';
+    bannerline[i] = '\0';
+
+    fprintf(logfiles[id].file, "%s\n", bannerline);
+    fprintf(logfiles[id].file, "%s\n", logfiles[id].banner);
+    fprintf(logfiles[id].file, "%s\n", bannerline);
+  }
+
+  va_start(other_args, format);
+  vfprintf(logfiles[id].file, format, other_args);
+  va_end(other_args);
+  fprintf(logfiles[id].file, "\n");
+
+  fflush(logfiles[id].file);
+}
+
+/* ================================================== */
+
+void
+LOG_CycleLogFiles(void)
+{
+  LOG_FileID i;
+
+  for (i = 0; i < n_filelogs; i++) {
+    if (logfiles[i].file)
+      fclose(logfiles[i].file);
+    logfiles[i].file = NULL;
+    logfiles[i].writes = 0;
+  }
+}
+
+/* ================================================== */