From 27aa1e14cbd0f248ccd7e8dbd403884795887b8d Mon Sep 17 00:00:00 2001
From: "Roger A. Light" <roger@atchoo.org>
Date: Wed, 29 Oct 2025 23:06:33 +0000
Subject: [PATCH] Fix libcommon log printing

---
 include/mosquitto/libcommon_file.h |  2 ++
 libcommon/file_common.c            | 27 +++++++++++++++++++++++----
 src/logging.c                      |  9 +++++++++
 3 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/include/mosquitto/libcommon_file.h b/include/mosquitto/libcommon_file.h
index 4ad3646a..2304a6e7 100644
--- a/include/mosquitto/libcommon_file.h
+++ b/include/mosquitto/libcommon_file.h
@@ -61,6 +61,8 @@ libmosqcommon_EXPORT int mosquitto_read_file(const char *file, bool restrict_rea
  */
 libmosqcommon_EXPORT char *mosquitto_trimblanks(char *str);
 
+extern void (*libcommon_vprintf)(const char *fmt, va_list va);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/libcommon/file_common.c b/libcommon/file_common.c
index 1ba4d8b3..4895ad41 100644
--- a/libcommon/file_common.c
+++ b/libcommon/file_common.c
@@ -24,6 +24,7 @@ Contributors:
 #include <ctype.h>
 #include <errno.h>
 #include <limits.h>
+#include <stdarg.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -46,6 +47,24 @@ Contributors:
 
 #include "mosquitto.h"
 
+void (*libcommon_vprintf)(const char *fmt, va_list va) = NULL;
+
+
+void libcommon_printf(const char *fmt, ...)
+{
+	va_list va;
+
+	va_start(va, fmt);
+
+	if(libcommon_vprintf){
+		libcommon_vprintf(fmt, va);
+	}else{
+		vfprintf(stderr, fmt, va);
+	}
+
+	va_end(va);
+}
+
 
 FILE *mosquitto_fopen(const char *path, const char *mode, bool restrict_read)
 {
@@ -185,7 +204,7 @@ FILE *mosquitto_fopen(const char *path, const char *mode, bool restrict_read)
 
 	if(restrict_read){
 		if(statbuf.st_mode & S_IRWXO){
-			fprintf(stderr,
+			libcommon_printf(
 					"Warning: File %s has world readable permissions. Future versions will refuse to load this file.\n"
 					"To fix this, use `chmod 0700 %s`.\n",
 					path, path);
@@ -199,7 +218,7 @@ FILE *mosquitto_fopen(const char *path, const char *mode, bool restrict_read)
 
 			getpwuid_r(getuid(), &pw, buf, sizeof(buf), &result);
 			if(result){
-				fprintf(stderr,
+				libcommon_printf(
 						"Warning: File %s owner is not %s. Future versions will refuse to load this file."
 						"To fix this, use `chown %s %s`.\n",
 						path, result->pw_name, result->pw_name, path);
@@ -214,7 +233,7 @@ FILE *mosquitto_fopen(const char *path, const char *mode, bool restrict_read)
 			struct group grp, *result;
 
 			if(getgrgid_r(getgid(), &grp, buf, sizeof(buf), &result) == 0){
-				fprintf(stderr,
+				libcommon_printf(
 						"Warning: File %s group is not %s. Future versions will refuse to load this file.\n",
 						path, result->gr_name);
 			}
@@ -226,7 +245,7 @@ FILE *mosquitto_fopen(const char *path, const char *mode, bool restrict_read)
 	}
 
 	if(!S_ISREG(statbuf.st_mode)){
-		fprintf(stderr, "Error: %s is not a file.", path);
+		libcommon_printf("Error: %s is not a file.", path);
 		fclose(fptr);
 		return NULL;
 	}
diff --git a/src/logging.c b/src/logging.c
index 6dc19044..8cdaabd4 100644
--- a/src/logging.c
+++ b/src/logging.c
@@ -50,6 +50,7 @@ static const char *LOG_TAG = "mosquitto";
 #endif
 
 static char log_fptr_buffer[BUFSIZ];
+static void libcommon__vprintf(const char *fmt, va_list va);
 
 /* Options for logging should be:
  *
@@ -114,6 +115,8 @@ int log__init(struct mosquitto__config *config)
 {
 	int rc = 0;
 
+	libcommon_vprintf = libcommon__vprintf;
+
 	log_priorities = config->log_type;
 	log_destinations = config->log_dest;
 
@@ -438,3 +441,9 @@ BROKER_EXPORT void mosquitto_log_printf(int level, const char *fmt, ...)
 	log__vprintf((unsigned int)level, fmt, va);
 	va_end(va);
 }
+
+
+static void libcommon__vprintf(const char *fmt, va_list va)
+{
+	log__vprintf(MOSQ_LOG_INFO, fmt, va);
+}