[PATCH v2] libtraceevent: Add back log functions for backward compatibility

[Steven Rostedt <rostedt@xxxxxxxxxxx>]

From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>

The following functions are obsolete and were removed:

  tep_vwarning()
  pr_stat()
  vpr_stat()
  __pr_stat()
  __vpr_stat()

But unfortunately they were part of a library release. Add them back as
all weak functions and label them deprecated.

Link: https://lore.kernel.org/linux-trace-devel/20210428073001.755905-1-tz.stoyanov@xxxxxxxxx/

Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
Changes since v1:
  Ported to the new version of "Add API to set severity to tracefs library logs"

 src/event-utils.h |  7 +++++++
 src/parse-utils.c | 16 ++++++++++++++++
 2 files changed, 23 insertions(+)

Index: libtraceevent.git/src/event-utils.h
===================================================================
--- libtraceevent.git.orig/src/event-utils.h
+++ libtraceevent.git/src/event-utils.h
@@ -15,6 +15,13 @@ void tep_info(const char *fmt, ...);
 int tep_vprint(const char *name, enum tep_loglevel level,
 	       bool print_err, const char *fmt, va_list ap);
 
+/* For backward compatibilty, do not use */
+int tep_vwarning(const char *name, const char *fmt, va_list ap);
+void pr_stat(const char *fmt, ...);
+void vpr_stat(const char *fmt, va_list ap);
+void __pr_stat(const char *fmt, ...);
+void __vpr_stat(const char *fmt, va_list ap);
+
 #define min(x, y) ({				\
 	typeof(x) _min1 = (x);			\
 	typeof(y) _min2 = (y);			\
Index: libtraceevent.git/src/parse-utils.c
===================================================================
--- libtraceevent.git.orig/src/parse-utils.c
+++ libtraceevent.git/src/parse-utils.c
@@ -79,3 +79,19 @@ void tep_info(const char *fmt, ...)
 	tep_vprint("libtraceevent", TEP_LOG_INFO, false, fmt, ap);
 	va_end(ap);
 }
+
+/* The below is for backward compatibility */
+int __weak tep_vwarning(const char *name, const char *fmt, va_list ap)
+{
+	return tep_vprint(name, TEP_LOG_WARNING, true, fmt, ap);
+}
+
+void pr_stat(const char *fmt, ...) __attribute__((weak, alias("tep_info")));
+void __pr_stat(const char *fmt, ...) __attribute__((weak, alias("tep_info")));
+
+void __weak __vpr_stat(const char *fmt, va_list ap)
+{
+	tep_vprint("libtraceevent", TEP_LOG_INFO, false, fmt, ap);
+}
+
+void vpr_stat(const char *fmt, va_list ap) __attribute__((weak, alias("__vpr_stat")));