MDEV-4472 Audit-plugin. Server-related part of the task.

     file_logger became the service.
     Data like query_id now are sent to the audit plugin.
     Fix for MDEV-4770 ported from 10.0.
     Fix added for the read_maria_plugin_info().
     Log rotation can be disabled with 'set rotations=0'.

1 files changed, 223 insertions, 0 deletions

diff --git a/mysys/file_logger.c b/mysys/file_logger.c
new file mode 100644
index 00000000000..4c07b8c7854
--- /dev/null
+++ b/mysys/file_logger.c
@@ -0,0 +1,223 @@
+/* Copyright (C) 2012 Monty Program Ab
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 of the License.
+
+   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+
+#include "my_global.h"
+#include <my_sys.h>
+#include <mysql/service_logger.h>
+#include <my_pthread.h>
+
+#ifdef HAVE_PSI_INTERFACE
+/* These belong to the service initialization */
+static PSI_mutex_key key_LOCK_logger_service;
+static PSI_mutex_info mutex_list[]=
+{{ &key_LOCK_logger_service, "logger_service_file_st::lock", PSI_FLAG_GLOBAL}};
+#endif
+
+typedef struct logger_handle_st {
+  File file;
+  char path[FN_REFLEN];
+  unsigned long long size_limit;
+  unsigned int rotations;
+  size_t path_len;
+  mysql_mutex_t lock;
+} LSFS;
+
+
+#define LOG_FLAGS (O_APPEND | O_CREAT | O_WRONLY)
+
+static unsigned int n_dig(unsigned int i)
+{
+  return (i == 0) ? 0 : ((i < 10) ? 1 : ((i < 100) ? 2 : 3));
+}
+
+
+LOGGER_HANDLE *logger_open(const char *path,
+                           unsigned long long size_limit,
+                           unsigned int rotations)
+{
+  LOGGER_HANDLE new_log, *l_perm;
+  /*
+    I don't think we ever need more rotations,
+    but if it's so, the rotation procedure should be adapted to it.
+  */
+  if (rotations > 999)
+    return 0;
+
+  new_log.rotations= rotations;
+  new_log.size_limit= size_limit;
+  new_log.path_len= strlen(fn_format(new_log.path, path,
+        mysql_data_home, "", MY_UNPACK_FILENAME));
+
+  if (new_log.path_len+n_dig(rotations)+1 > FN_REFLEN)
+  {
+    errno= ENAMETOOLONG;
+    /* File path too long */
+    return 0;
+  }
+  if ((new_log.file= my_open(new_log.path, LOG_FLAGS, MYF(0))) < 0)
+  {
+    errno= my_errno;
+    /* Check errno for the cause */
+    return 0;
+  }
+
+  if (!(l_perm= (LOGGER_HANDLE *) my_malloc(sizeof(LOGGER_HANDLE), MYF(0))))
+  {
+    my_close(new_log.file, MYF(0));
+    new_log.file= -1;
+    return 0; /* End of memory */
+  }
+  *l_perm= new_log;
+  mysql_mutex_init(key_LOCK_logger_service, &l_perm->lock, MY_MUTEX_INIT_FAST);
+  return l_perm;
+}
+
+int logger_close(LOGGER_HANDLE *log)
+{
+  int result;
+  File file= log->file;
+  mysql_mutex_destroy(&log->lock);
+  my_free(log);
+  if ((result= my_close(file, MYF(0))))
+    errno= my_errno;
+  return result;
+}
+
+
+static char *logname(LOGGER_HANDLE *log, char *buf, unsigned int n_log)
+{
+  sprintf(buf+log->path_len, ".%0*u", n_dig(log->rotations), n_log);
+  return buf;
+}
+
+
+static int do_rotate(LOGGER_HANDLE *log)
+{
+  char namebuf[FN_REFLEN];
+  int result;
+  unsigned int i;
+  char *buf_old, *buf_new, *tmp;
+
+  if (log->rotations == 0)
+    return 0;
+
+  memcpy(namebuf, log->path, log->path_len);
+
+  buf_new= logname(log, namebuf, log->rotations);
+  buf_old= log->path;
+  for (i=log->rotations-1; i>0; i--)
+  {
+    logname(log, buf_old, i);
+    if (!access(buf_old, F_OK) &&
+        (result= my_rename(buf_old, buf_new, MYF(0))))
+      goto exit;
+    tmp= buf_old;
+    buf_old= buf_new;
+    buf_new= tmp;
+  }
+  if ((result= my_close(log->file, MYF(0))))
+    goto exit;
+  namebuf[log->path_len]= 0;
+  result= my_rename(namebuf, logname(log, log->path, 1), MYF(0));
+  log->file= my_open(namebuf, LOG_FLAGS, MYF(0));
+exit:
+  errno= my_errno;
+  return log->file < 0 || result;
+}
+
+
+int logger_vprintf(LOGGER_HANDLE *log, const char* fmt, va_list ap)
+{
+  int result;
+  my_off_t filesize;
+  char cvtbuf[1024];
+  size_t n_bytes;
+
+  mysql_mutex_lock(&log->lock);
+  if (log->rotations > 0)
+    if ((filesize= my_tell(log->file, MYF(0))) == (my_off_t) -1 ||
+        ((unsigned long long)filesize >= log->size_limit &&
+         do_rotate(log)))
+    {
+      result= -1;
+      errno= my_errno;
+      goto exit; /* Log rotation needed but failed */
+    }
+
+  n_bytes= my_vsnprintf(cvtbuf, sizeof(cvtbuf), fmt, ap);
+  if (n_bytes >= sizeof(cvtbuf))
+    n_bytes= sizeof(cvtbuf) - 1;
+
+  result= my_write(log->file, (uchar *) cvtbuf, n_bytes, MYF(0));
+
+exit:
+  mysql_mutex_unlock(&log->lock);
+  return result;
+}
+
+
+int logger_write(LOGGER_HANDLE *log, const char *buffer, size_t size)
+{
+  int result;
+  my_off_t filesize;
+
+  mysql_mutex_lock(&log->lock);
+  if (log->rotations > 0)
+    if ((filesize= my_tell(log->file, MYF(0))) == (my_off_t) -1 ||
+        ((unsigned long long)filesize >= log->size_limit &&
+         do_rotate(log)))
+    {
+      result= -1;
+      errno= my_errno;
+      goto exit; /* Log rotation needed but failed */
+    }
+
+  result= my_write(log->file, (uchar *) buffer, size, MYF(0));
+
+exit:
+  mysql_mutex_unlock(&log->lock);
+  return result;
+}
+
+
+int logger_rotate(LOGGER_HANDLE *log)
+{
+  int result;
+  mysql_mutex_lock(&log->lock);
+  result= do_rotate(log);
+  mysql_mutex_unlock(&log->lock);
+  return result;
+}
+
+
+int logger_printf(LOGGER_HANDLE *log, const char *fmt, ...)
+{
+  int result;
+  va_list args;
+  va_start(args,fmt);
+  result= logger_vprintf(log, fmt, args);
+  va_end(args);
+  return result;
+}
+
+void logger_init_mutexes()
+{
+#ifdef HAVE_PSI_INTERFACE
+  if (PSI_server)
+    PSI_server->register_mutex("sql_logger", mutex_list, 1);
+#endif
+}
+