Add logging callback (#201)

* Add possibility to replace default logging function with provided callback.

Author: KGronek-Pubnub

.pubnub.yml

@@ -1,8 +1,13 @@
 name: c-core
 schema: 1
-version: "4.16.1"
+version: "4.17.0"
 scm: github.com/pubnub/c-core
 changelog:
+  - date: 2025-01-16
+    version: v4.17.0
+    changes:
+      - type: feature
+        text: "Add possibility to replace default log function with a callback provided by the user."
   - date: 2025-01-09
     version: v4.16.1
     changes:
@@ -902,7 +907,7 @@ sdks:
             distribution-type: source code
             distribution-repository: GitHub release
             package-name: C-Core
-            location: https://github.com/pubnub/c-core/releases/tag/v4.16.1
+            location: https://github.com/pubnub/c-core/releases/tag/v4.17.0
             requires:
               -
                 name: "miniz"
@@ -968,7 +973,7 @@ sdks:
             distribution-type: source code
             distribution-repository: GitHub release
             package-name: C-Core
-            location: https://github.com/pubnub/c-core/releases/tag/v4.16.1
+            location: https://github.com/pubnub/c-core/releases/tag/v4.17.0
             requires:
               -
                 name: "miniz"
@@ -1034,7 +1039,7 @@ sdks:
             distribution-type: source code
             distribution-repository: GitHub release
             package-name: C-Core
-            location: https://github.com/pubnub/c-core/releases/tag/v4.16.1
+            location: https://github.com/pubnub/c-core/releases/tag/v4.17.0
             requires:
               -
                 name: "miniz"
@@ -1096,7 +1101,7 @@ sdks:
             distribution-type: source code
             distribution-repository: GitHub release
             package-name: C-Core
-            location: https://github.com/pubnub/c-core/releases/tag/v4.16.1
+            location: https://github.com/pubnub/c-core/releases/tag/v4.17.0
             requires:
               -
                 name: "miniz"
@@ -1157,7 +1162,7 @@ sdks:
             distribution-type: source code
             distribution-repository: GitHub release
             package-name: C-Core
-            location: https://github.com/pubnub/c-core/releases/tag/v4.16.1
+            location: https://github.com/pubnub/c-core/releases/tag/v4.17.0
             requires:
               -
                 name: "miniz"
@@ -1213,7 +1218,7 @@ sdks:
             distribution-type: source code
             distribution-repository: GitHub release
             package-name: C-Core
-            location: https://github.com/pubnub/c-core/releases/tag/v4.16.1
+            location: https://github.com/pubnub/c-core/releases/tag/v4.17.0
             requires:
               -
                 name: "miniz"
@@ -1266,7 +1271,7 @@ sdks:
             distribution-type: source code
             distribution-repository: GitHub release
             package-name: C-Core
-            location: https://github.com/pubnub/c-core/releases/tag/v4.16.1
+            location: https://github.com/pubnub/c-core/releases/tag/v4.17.0
             requires:
               -
                 name: "miniz"

CHANGELOG.md

@@ -1,3 +1,9 @@
+## v4.17.0
+January 16 2025
+
+#### Added
+- Add possibility to replace default log function with a callback provided by the user.
+
 ## v4.16.1
 January 09 2025
 

CMakeLists.txt

@@ -84,6 +84,7 @@ num_option(USE_IPV6 "Use IPv6" ON)
 num_option(USE_SET_DNS_SERVERS "Use set DNS servers [CALLBACK=ON]" ${DEFAULT_USE_CALLBACK_API})
 num_option(USE_EXTERN_API "Use extern C API [WITH_CPP=ON]" ON)
 num_option(USE_LEGACY_CRYPTO_RANDOM_IV "Use random IV for legacy crypto module [OpenSSL only]" ON)
+num_option(USE_LOG_CALLBACK "Use possibility to replace default logging function with user provided callback" OFF)
 log_set(OPENSSL_ROOT_DIR "" "OpenSSL root directory (leave empty for find_package() defaults)[OPENSSL=ON needed]")
 log_set(CUSTOM_OPENSSL_LIB_DIR "lib" "OpenSSL lib directory relative to OPENSSL_ROOT_DIR [used only if find_package() failed]")
 log_set(CUSTOM_OPENSSL_INCLUDE_DIR "include" "OpenSSL include directory relative to OPENSSL_ROOT_DIR [used only if find_package() failed]")
@@ -118,6 +119,7 @@ set(FLAGS "\
     -D PUBNUB_USE_FETCH_HISTORY=${USE_FETCH_HISTORY} \
     -D PUBNUB_CRYPTO_API=${USE_CRYPTO_API} \
     -D PUBNUB_RAND_INIT_VECTOR=${USE_LEGACY_CRYPTO_RANDOM_IV} \
+    -D PUBNUB_USE_LOG_CALLBACK=${USE_LOG_CALLBACK} \
     -D PUBNUB_MBEDTLS=${MBEDTLS}")
 
 #Required on windows with Event Engine, so only winsock2 is used (otherwise it tries to use winsock and winsock2 and there are redefinition errors)
@@ -182,6 +184,7 @@ set(CORE_SOURCEFILES
         ${CMAKE_CURRENT_LIST_DIR}/core/pubnub_netcore.c
         ${CMAKE_CURRENT_LIST_DIR}/core/pubnub_blocking_io.c
         ${CMAKE_CURRENT_LIST_DIR}/core/pubnub_timers.c
+        ${CMAKE_CURRENT_LIST_DIR}/core/pubnub_log.c
         ${CMAKE_CURRENT_LIST_DIR}/core/pubnub_json_parse.c
         ${CMAKE_CURRENT_LIST_DIR}/core/pubnub_helper.c
         ${CMAKE_CURRENT_LIST_DIR}/core/pubnub_generate_uuid_v3_md5.c

core/Makefile

@@ -1,4 +1,4 @@
-PROJECT_SOURCEFILES = pbcc_set_state.c pubnub_pubsubapi.c pubnub_coreapi.c pubnub_ccore_pubsub.c pubnub_ccore.c pubnub_netcore.c pubnub_alloc_static.c pubnub_assert_std.c pubnub_json_parse.c pubnub_keep_alive.c pubnub_helper.c pubnub_url_encode.c ../lib/pb_strnlen_s.c ../lib/pb_strncasecmp.c ../lib/base64/pbbase64.c pubnub_coreapi_ex.c
+PROJECT_SOURCEFILES = pbcc_set_state.c pubnub_pubsubapi.c pubnub_coreapi.c pubnub_ccore_pubsub.c pubnub_ccore.c pubnub_netcore.c pubnub_alloc_static.c pubnub_assert_std.c pubnub_json_parse.c pubnub_keep_alive.c pubnub_helper.c pubnub_url_encode.c ../lib/pb_strnlen_s.c ../lib/pb_strncasecmp.c ../lib/base64/pbbase64.c pubnub_coreapi_ex.c pubnub_log.c
 # TODO: move coreapi_ex to new module
 
 all: pubnub_crypto_unittest pubnub_subscribe_v2_unittest pbcc_crypto_unittest pubnub_grant_token_api_unittest pubnub_proxy_unittest pubnub_timer_list_unittest unittest
@@ -57,7 +57,7 @@ unittest: $(PROJECT_SOURCEFILES) pubnub_core_unit_test.c
 	#$(GCOVR) -r . --html --html-details -o coverage.html
 
 
-TIMER_LIST_SOURCEFILES = pubnub_alloc_static.c pubnub_assert_std.c pubnub_timers.c
+TIMER_LIST_SOURCEFILES = pubnub_alloc_static.c pubnub_assert_std.c pubnub_timers.c pubnub_log.c
 
 pubnub_timer_list_unittest: pubnub_timer_list.c pubnub_timer_list_unit_test.c
 	gcc -o pubnub_timer_list_unit_test.so -shared $(CFLAGS) $(LDFLAGS) -D PUBNUB_CALLBACK_API -D PUBNUB_ASSERT_LEVEL_NONE -Wall $(COVERAGE_FLAGS) -fPIC $(TIMER_LIST_SOURCEFILES) pubnub_timer_list.c pubnub_timer_list_unit_test.c -lcgreen -lm

core/pubnub_internal_common.h

@@ -17,6 +17,10 @@
 #define PUBNUB_USE_IPV6 0
 #endif
 
+#if !defined(PUBNUB_USE_LOG_CALLBACK)
+#define PUBNUB_USE_LOG_CALLBACK 0
+#endif
+
 #if !defined(PUBNUB_SET_DNS_SERVERS)
 #define PUBNUB_SET_DNS_SERVERS 0
 #endif

core/pubnub_log.c

@@ -0,0 +1,39 @@
+/* -*- c-file-style:"stroustrup"; indent-tabs-mode: nil -*- */
+#include "pubnub_log.h"
+
+#if PUBNUB_USE_LOG_CALLBACK
+
+#include <stddef.h>
+#include <stdarg.h>
+#include <stdlib.h>
+
+void (*pubnub_log_callback)(enum pubnub_log_level log_level, const char* message) = NULL;
+
+void pubnub_set_log_callback(void (*callback)(enum pubnub_log_level log_level, const char* message)) {
+    pubnub_log_callback = callback;
+}
+
+void log_with_callback(enum pubnub_log_level log_level, const char* format, ...) {
+    //Check needed buffer size for the message
+    va_list args;
+    va_start(args, format);
+    int needed_size = vsnprintf(NULL, 0, format, args) + 1;
+    va_end(args);
+
+    if(needed_size <= 0) {return;}
+
+    //Allocate required size to the message
+    char* logMessage = (char*)malloc(needed_size);
+    if (!logMessage) {return;}
+
+    //Format string with message and all parameters
+    va_start(args, format);
+    vsnprintf(logMessage, needed_size, format, args);
+    va_end(args);
+
+    //Execute the callback
+    pubnub_log_callback(log_level, logMessage);
+    free(logMessage);
+}
+
+#endif /* PUBNUB_USE_LOG_CALLBACK */

core/pubnub_log.h

@@ -43,10 +43,45 @@ enum pubnub_log_level {
 #define PUBNUB_LOG_PRINTF(...) printf(__VA_ARGS__)
 #endif
 
+#if PUBNUB_USE_LOG_CALLBACK
+
+#include "../lib/pb_extern.h"
+
+/** A global variable to store log function provided by the user.
+    This shouldn't be accessed or set directly. Use pubnub_set_log_callback instead.
+*/
+extern void (*pubnub_log_callback)(enum pubnub_log_level log_level, const char* message);
+
+/** Replaces default logging function "printf" with provided callback.
+
+    @param callback The callback that will be executed instead of default log
+ */
+PUBNUB_EXTERN void pubnub_set_log_callback(void (*callback)(enum pubnub_log_level log_level, const char* message));
+
+void log_with_callback(enum pubnub_log_level log_level, const char* format, ...);
+
+//Redefine this macro to include callback functionality
 /** Generic logging macro, logs to given @a LVL using a printf-like
-    interface
+    interface. Uses callback instead of printf if pubnub_log_callback
+    is set.
+*/
+#define PUBNUB_LOG(LVL, ...) \
+do { \
+    if (LVL <= PUBNUB_LOG_LEVEL) { \
+        if (pubnub_log_callback) { \
+            log_with_callback(LVL, __VA_ARGS__); \
+        } else { \
+            PUBNUB_LOG_PRINTF(__VA_ARGS__); \
+        } \
+    } \
+} while(0)
+#else
+/** Generic logging macro, logs to given @a LVL using a printf-like
+    interface.
 */
 #define PUBNUB_LOG(LVL, ...) do { if (LVL <= PUBNUB_LOG_LEVEL) PUBNUB_LOG_PRINTF(__VA_ARGS__); } while(0)
+#endif /* PUBNUB_USE_LOG_CALLBACK */
+
 
 /** Helper macro to log an error message */
 #define PUBNUB_LOG_ERROR(...) PUBNUB_LOG(PUBNUB_LOG_LEVEL_ERROR, __VA_ARGS__)
@@ -108,4 +143,4 @@ enum pubnub_log_level {
 
 
 
-#endif /*!defined INC_PUBNUB_LOG*/
+#endif /* !defined INC_PUBNUB_LOG */

core/pubnub_version_internal.h

@@ -3,7 +3,7 @@
 #define INC_PUBNUB_VERSION_INTERNAL
 
 
-#define PUBNUB_SDK_VERSION "4.16.1"
+#define PUBNUB_SDK_VERSION "4.17.0"
 
 
 #endif /* !defined INC_PUBNUB_VERSION_INTERNAL */

core/test/pubnub_config.h

@@ -118,6 +118,10 @@
 #define PUBNUB_RECEIVE_GZIP_RESPONSE 1
 #endif
 
+#if !defined(PUBNUB_USE_LOG_CALLBACK)
+#define PUBNUB_USE_LOG_CALLBACK 0
+#endif
+
 #define PUBNUB_DEFAULT_TRANSACTION_TIMER    310000
 
 #define PUBNUB_MIN_TRANSACTION_TIMER 200

make/common/preprocessing.mk

@@ -31,7 +31,8 @@ DEFINES_COMMON = \
     $(OPTION_PREFIX)D PUBNUB_USE_REVOKE_TOKEN_API=$(USE_REVOKE_TOKEN)                 \
     $(OPTION_PREFIX)D PUBNUB_USE_SSL=$(USE_SSL)                                       \
     $(OPTION_PREFIX)D PUBNUB_USE_SUBSCRIBE_EVENT_ENGINE=$(USE_SUBSCRIBE_EVENT_ENGINE) \
-    $(OPTION_PREFIX)D PUBNUB_USE_SUBSCRIBE_V2=$(USE_SUBSCRIBE_V2)
+    $(OPTION_PREFIX)D PUBNUB_USE_SUBSCRIBE_V2=$(USE_SUBSCRIBE_V2)                     \
+    $(OPTION_PREFIX)D PUBNUB_USE_LOG_CALLBACK=$(USE_LOG_CALLBACK)
 
 # Preprocessing flags for synchronous PubNub library version.
 CPPFLAGS_ = $(INCLUDES) $(DEFINES_PLATFORM) $(DEFINES_COMMON) $(DEFINES_EXTERN_C) $(DEFINES_RANDOM_IV)

make/common/preprocessing_defaults.mk

@@ -81,4 +81,7 @@ DEFAULT_USE_REVOKE_TOKEN = 0
 DEFAULT_USE_SUBSCRIBE_EVENT_ENGINE = 0
 
 # Whether subscribe v2 feature should be enabled or not.
-DEFAULT_USE_SUBSCRIBE_V2 = 1
+DEFAULT_USE_SUBSCRIBE_V2 = 1
+
+# Whether user defined callback for logging should be enabled or not.
+DEFAULT_USE_LOG_CALLBACK = 0

make/common/source_files.mk

@@ -22,6 +22,7 @@ CORE_SOURCE_FILES = \
     ../core/pubnub_generate_uuid_v3_md5.c             \
     ../core/pubnub_helper.c                           \
     ../core/pubnub_json_parse.c                       \
+    ../core/pubnub_log.c                              \
     ../core/pubnub_memory_block.c                     \
     ../core/pubnub_netcore.c                          \
     ../core/pubnub_pubsubapi.c                        \

make/posix_preprocessing.mk

@@ -143,6 +143,9 @@ USE_SUBSCRIBE_EVENT_ENGINE ?= $(DEFAULT_USE_SUBSCRIBE_EVENT_ENGINE)
 # Whether subscribe v2 feature should be enabled or not.
 USE_SUBSCRIBE_V2 ?= $(DEFAULT_USE_SUBSCRIBE_V2)
 
+# Whether user defined callback for logging should be enabled or not.
+USE_LOG_CALLBACK ?= $(DEFAULT_USE_LOG_CALLBACK)
+
 # Additional user-provided compiler flags (C/C++).
 USER_C_FLAGS ?=
 USER_CXX_FLAGS ?=

make/windows_preprocessing.mk

@@ -218,6 +218,11 @@ USE_SUBSCRIBE_EVENT_ENGINE = $(DEFAULT_USE_SUBSCRIBE_EVENT_ENGINE)
 USE_SUBSCRIBE_V2 = $(DEFAULT_USE_SUBSCRIBE_V2)
 !endif
 
+# Whether user defined callback for logging should be enabled or not.
+!ifndef USE_LOG_CALLBACK
+USE_LOG_CALLBACK = $(DEFAULT_USE_LOG_CALLBACK)
+!endif
+
 # Additional user-provided compiler flags (C/C++).
 !ifndef USER_C_FLAGS
 USER_C_FLAGS =

openssl/pubnub_config.h

@@ -159,6 +159,10 @@
 #define PUBNUB_COMPRESSED_MAXLEN 32000
 #endif
 
+#if !defined(PUBNUB_USE_LOG_CALLBACK)
+#define PUBNUB_USE_LOG_CALLBACK 1
+#endif
+
 /** The maximum length (in characters) of the host name of the proxy
     that will be saved in the Pubnub context.
 */

posix/pubnub_config.h

@@ -161,6 +161,9 @@
 #define PUBNUB_CRYPTO_API 0
 #endif
 
+#if !defined(PUBNUB_USE_LOG_CALLBACK)
+#define PUBNUB_USE_LOG_CALLBACK 0
+#endif
 
 #if !defined(PUBNUB_ONLY_PUBSUB_API)
 /** If true (!=0), will enable only publish and subscribe. All

windows/pubnub_config.h

@@ -162,6 +162,9 @@
 #define PUBNUB_CRYPTO_API 0
 #endif
 
+#if !defined(PUBNUB_USE_LOG_CALLBACK)
+#define PUBNUB_USE_LOG_CALLBACK 0
+#endif
 
 #if !defined(PUBNUB_ONLY_PUBSUB_API)
 /** If true (!=0), will enable only publish and subscribe. All