Provide log_status_format(), useful for an emit_log_hook.

Refactor so that log_line_prefix() is a thin wrapper over a new
function log_status_format(), and move the implementation to the
latter. Export log_status_format() so that it can be used by an
emit_log_hook.

Discussion: https://postgr.es/m/39c8197652f4d3050aedafae79fa5af31096505f.camel%40j-davis.com
Reviewed-by: Michael Paquier, Alvaro Herrera

diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index 59124bd9ccb86a32ac42ca8b9cb4a6f0f01ff13d..95f32de4e29c6b9bd79a52e9f1b677db5de18743 100644 (file)
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -2438,10 +2438,19 @@ process_log_prefix_padding(const char *p, int *ppadding)
 }
 
 /*
- * Format tag info for log lines; append to the provided buffer.
+ * Format log status information using Log_line_prefix.
  */
 static void
 log_line_prefix(StringInfo buf, ErrorData *edata)
+{
+   log_status_format(buf, Log_line_prefix, edata);
+}
+
+/*
+ * Format log status info; append to the provided buffer.
+ */
+void
+log_status_format(StringInfo buf, const char *format, ErrorData *edata)
 {
    /* static counter for line numbers */
    static long log_line_number = 0;
@@ -2465,10 +2474,10 @@ log_line_prefix(StringInfo buf, ErrorData *edata)
    }
    log_line_number++;
 
-   if (Log_line_prefix == NULL)
+   if (format == NULL)
        return;                 /* in case guc hasn't run yet */
 
-   for (p = Log_line_prefix; *p != '\0'; p++)
+   for (p = format; *p != '\0'; p++)
    {
        if (*p != '%')
        {

diff --git a/src/include/utils/elog.h b/src/include/utils/elog.h
index f5c6cd904de925db6819e56e4869a27b620b090c..68ead8e8736587cb2d248f9ef5a72f81f4bf7356 100644 (file)
--- a/src/include/utils/elog.h
+++ b/src/include/utils/elog.h
@@ -16,6 +16,8 @@
 
 #include <setjmp.h>
 
+#include "lib/stringinfo.h"
+
 /* Error level codes */
 #define DEBUG5     10          /* Debugging messages, in categories of
                                 * decreasing detail. */
@@ -439,6 +441,8 @@ extern PGDLLIMPORT bool syslog_split_messages;
 #define LOG_DESTINATION_JSONLOG    16
 
 /* Other exported functions */
+extern void log_status_format(StringInfo buf, const char *format,
+                             ErrorData *edata);
 extern void DebugFileOpen(void);
 extern char *unpack_sql_state(int sql_state);
 extern bool in_error_recursion_trouble(void);