[PATCH v21 10/14] log: add hook for printing log messages

[Stephen Hemminger]

This is useful for when decorating log output for console
or journal. Provide basic version in this patch.

Signed-off-by: Stephen Hemminger <step...@networkplumber.org>
---
 lib/log/log.c         | 7 ++++++-
 lib/log/log_private.h | 9 +++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)
 create mode 100644 lib/log/log_private.h

diff --git a/lib/log/log.c b/lib/log/log.c
index 3fe86ddcd7..979b20c3ef 100644
--- a/lib/log/log.c
+++ b/lib/log/log.c
@@ -18,6 +18,7 @@
 #include <rte_per_lcore.h>
 
 #include "log_internal.h"
+#include "log_private.h"
 
 #ifdef RTE_EXEC_ENV_WINDOWS
 #define strdup _strdup
@@ -28,16 +29,19 @@ struct rte_log_dynamic_type {
        uint32_t loglevel;
 };
 
+
 /** The rte_log structure. */
 static struct rte_logs {
        uint32_t type;  /**< Bitfield with enabled logs. */
        uint32_t level; /**< Log level. */
        FILE *file;     /**< Output file set by rte_openlog_stream, or NULL. */
+       log_print_t print_func;
        size_t dynamic_types_len;
        struct rte_log_dynamic_type *dynamic_types;
 } rte_logs = {
        .type = UINT32_MAX,
        .level = RTE_LOG_DEBUG,
+       .print_func = vfprintf,
 };
 
 struct rte_eal_opt_loglevel {
@@ -74,6 +78,7 @@ int
 rte_openlog_stream(FILE *f)
 {
        rte_logs.file = f;
+       rte_logs.print_func = vfprintf;
        return 0;
 }
 
@@ -470,7 +475,7 @@ rte_vlog(uint32_t level, uint32_t logtype, const char 
*format, va_list ap)
        RTE_PER_LCORE(log_cur_msg).loglevel = level;
        RTE_PER_LCORE(log_cur_msg).logtype = logtype;
 
-       ret = vfprintf(f, format, ap);
+       ret = (*rte_logs.print_func)(f, format, ap);
        fflush(f);
        return ret;
 }
diff --git a/lib/log/log_private.h b/lib/log/log_private.h
new file mode 100644
index 0000000000..67d2463b2f
--- /dev/null
+++ b/lib/log/log_private.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef LOG_PRIVATE_H
+#define LOG_PRIVATE_H
+
+/* Note: same as vfprintf() */
+typedef int (*log_print_t)(FILE *f, const char *fmt, va_list ap);
+
+#endif /* LOG_PRIVATE_H */
-- 
2.43.0