Changed C library to enable debug prints at runtime (enabled automati…

…cally in C++ when VLOG is set for polaris_client).

Merge pull request #39.

c/BUILD

@@ -2,6 +2,23 @@ package(default_visibility = ["//visibility:public"])
 
 load("@bazel_skylib//rules:common_settings.bzl", "bool_flag")
 
+# Option to disable _all_ print messages:
+#   --//:polaris_enable_print       [enabled; default]
+#   --//:polaris_enable_print=True  [enabled; default]
+#   --//:polaris_enable_print=False [disabled]
+#   --no//:polaris_enable_print     [disabled]
+bool_flag(
+    name = "polaris_enable_print",
+    build_setting_default = True,
+)
+
+config_setting(
+    name = "print_enabled",
+    flag_values = {
+        ":polaris_enable_print": "True",
+    },
+)
+
 # Option to enable/disable TLS support (enabled by default):
 #   --//:polaris_enable_tls       [enabled; default]
 #   --//:polaris_enable_tls=True  [enabled; default]
@@ -38,7 +55,11 @@ cc_library(
     name = "polaris_client_tls",
     srcs = glob(["src/**/*.c"]),
     hdrs = glob(["src/**/*.h"]),
-    copts = ["-DPOLARIS_USE_TLS=1"],
+    copts = ["-DPOLARIS_USE_TLS=1"] +
+            select({
+                ":print_enabled": [],
+                "//conditions:default": ["-DPOLARIS_NO_PRINT"],
+            }),
     includes = ["src"],
     deps = ["@boringssl//:ssl"],
 )
@@ -49,5 +70,9 @@ cc_library(
     name = "polaris_client_no_tls",
     srcs = glob(["src/**/*.c"]),
     hdrs = glob(["src/**/*.h"]),
+    copts = select({
+        ":print_enabled": [],
+        "//conditions:default": ["-DPOLARIS_NO_PRINT"],
+    }),
     includes = ["src"],
 )

c/CMakeLists.txt

@@ -9,9 +9,8 @@ option(BUILD_SHARED_LIBS "Build shared libraries instead of static libraries."
 
 option(BUILD_EXAMPLES "Build example applications." ON)
 
-set(POLARIS_DEBUG "OFF" CACHE STRING
-    "Enable Polaris debug/trace print messages.")
-set_property(CACHE POLARIS_DEBUG PROPERTY STRINGS OFF ON DEBUG TRACE)
+option(POLARIS_ENABLE_PRINT
+       "Enable Polaris debug/trace print messages." ON)
 
 option(POLARIS_ENABLE_TLS "Enable TLS support when connecting to Polaris." ON)
 
@@ -22,10 +21,8 @@ else()
     add_compile_options(-Wall -Werror)
 endif()
 
-if(POLARIS_DEBUG STREQUAL "TRACE")
-    add_compile_definitions(POLARIS_TRACE)
-elseif(POLARIS_DEBUG)
-    add_compile_definitions(POLARIS_DEBUG)
+if(NOT POLARIS_ENABLE_PRINT)
+    add_compile_definitions(POLARIS_NO_PRINT)
 endif()
 
 ################################################################################

c/examples/connection_retry.c

@@ -5,6 +5,7 @@
  ******************************************************************************/
 
 #include <signal.h>
+#include <stdlib.h> // For atoi()
 
 #include "point_one/polaris/polaris.h"
 #include "point_one/polaris/portability.h"
@@ -26,13 +27,16 @@ void HandleSignal(int sig) {
 
 int main(int argc, const char* argv[]) {
   if (argc < 2 || argc > 3) {
-    P1_fprintf(stderr, "Usage: %s API_KEY [UNIQUE_ID]\n", argv[0]);
+    P1_fprintf(stderr, "Usage: %s API_KEY [UNIQUE_ID] [LOG_LEVEL]\n", argv[0]);
     return 1;
   }
 
   const char* api_key = argv[1];
   const char* unique_id = argc > 2 ? argv[2] : "device12345";
 
+  int log_level = argc > 3 ? atoi(argv[3]) : POLARIS_LOG_LEVEL_INFO;
+  Polaris_SetLogLevel(log_level);
+
   const int MAX_RECONNECTS = 2;
   int auth_valid = 0;
   int reconnect_count = 0;

c/examples/simple_polaris_client.c

@@ -5,6 +5,7 @@
  ******************************************************************************/
 
 #include <signal.h>
+#include <stdlib.h> // For atoi()
 
 #include "point_one/polaris/polaris.h"
 #include "point_one/polaris/portability.h"
@@ -26,13 +27,16 @@ void HandleSignal(int sig) {
 
 int main(int argc, const char* argv[]) {
   if (argc < 2 || argc > 3) {
-    P1_fprintf(stderr, "Usage: %s API_KEY [UNIQUE_ID]\n", argv[0]);
+    P1_fprintf(stderr, "Usage: %s API_KEY [UNIQUE_ID] [LOG_LEVEL]\n", argv[0]);
     return 1;
   }
 
   const char* api_key = argv[1];
   const char* unique_id = argc > 2 ? argv[2] : "device12345";
 
+  int log_level = argc > 3 ? atoi(argv[3]) : POLARIS_LOG_LEVEL_INFO;
+  Polaris_SetLogLevel(log_level);
+
   // Retrieve an access token using the specified API key.
   if (Polaris_Init(&context) != POLARIS_SUCCESS) {
     return 2;

c/src/point_one/polaris/polaris.c

@@ -22,12 +22,39 @@
 #define MAKE_STR(x) #x
 #define STR(x) MAKE_STR(x)
 
-#define P1_Print(x, ...) \
+#if defined(P1_NO_PRINT)
+# define P1_Print(x, ...) do {} while(0)
+# define P1_PrintError(x, ...) do {} while(0)
+# define P1_DebugPrint(x, ...) do {} while(0)
+# define PrintData(buffer, length) do {} while(0)
+# if defined(POLARIS_USE_TLS)
+#  define ShowCerts(ssl) do {} while(0)
+# endif
+#else
+static int __log_level = POLARIS_LOG_LEVEL_INFO;
+
+# define P1_Print(x, ...) \
   P1_fprintf(stderr, "polaris.c:" STR(__LINE__) "] " x, ##__VA_ARGS__)
-#define P1_PrintError(x, ...) \
+# define P1_PrintError(x, ...) \
   P1_perror("polaris.c:" STR(__LINE__) "] " x, ##__VA_ARGS__)
+# define P1_DebugPrint(x, ...)              \
+  if (__log_level >= POLARIS_LOG_LEVEL_DEBUG) {  \
+    P1_Print(x, ##__VA_ARGS__);             \
+  }
+# define P1_TracePrint(x, ...)              \
+  if (__log_level >= POLARIS_LOG_LEVEL_TRACE) {  \
+    P1_Print(x, ##__VA_ARGS__);             \
+  }
+
+static void P1_PrintData(const uint8_t* buffer, size_t length);
+# if defined(POLARIS_USE_TLS)
+static void ShowCerts(SSL* ssl);
+# endif
+#endif
 
-#if defined(POLARIS_USE_TLS)
+#if defined(POLARIS_NO_PRINT)
+# define P1_PrintWriteError(context, x, ret) do {} while(0)
+#elif defined(POLARIS_USE_TLS)
 static void __P1_PrintWriteError(int line, PolarisContext_t* context,
                                  const char* message, int ret) {
   SSL_load_error_strings();
@@ -80,40 +107,10 @@ static void __P1_PrintWriteError(int line, PolarisContext_t* context,
   }
 }
 
-#define P1_PrintWriteError(context, x, ret) \
+# define P1_PrintWriteError(context, x, ret) \
   __P1_PrintWriteError(__LINE__, context, x, ret)
 #else
-#define P1_PrintWriteError(context, x, ret) P1_PrintError(x, ret)
-#endif
-
-
-#if defined(POLARIS_TRACE) && !defined(POLARIS_DEBUG)
-# define POLARIS_DEBUG 1
-#endif
-
-#if defined(POLARIS_DEBUG) || defined(POLARIS_TRACE)
-# define P1_DebugPrint(x, ...) P1_Print(x, ##__VA_ARGS__)
-#else
-# define P1_DebugPrint(x, ...) do {} while(0)
-#endif
-
-#if defined(POLARIS_TRACE)
-void PrintData(const uint8_t* buffer, size_t length) {
-  for (size_t i = 0; i < length; ++i) {
-    if (i % 16 != 0) {
-      P1_fprintf(stderr, " ");
-    }
-
-    P1_fprintf(stderr, "%02x", buffer[i]);
-
-    if (i % 16 == 15) {
-      P1_fprintf(stderr, "\n");
-    }
-  }
-  P1_fprintf(stderr, "\n");
-}
-#else
-# define PrintData(buffer, length) do {} while(0)
+# define P1_PrintWriteError(context, x, ret) P1_PrintError(x, ret)
 #endif
 
 static int OpenSocket(PolarisContext_t* context, const char* endpoint_url,
@@ -127,10 +124,6 @@ static int GetHTTPResponse(PolarisContext_t* context);
 
 static void CloseSocket(PolarisContext_t* context, int destroy_context);
 
-#ifdef POLARIS_USE_TLS
-static void ShowCerts(SSL* ssl);
-#endif
-
 /******************************************************************************/
 int Polaris_Init(PolarisContext_t* context) {
   if (POLARIS_RECV_BUFFER_SIZE < POLARIS_MAX_HTTP_MESSAGE_SIZE) {
@@ -167,6 +160,13 @@ void Polaris_Free(PolarisContext_t* context) {
   CloseSocket(context, 1);
 }
 
+/******************************************************************************/
+void Polaris_SetLogLevel(int log_level) {
+#if !defined(POLARIS_NO_PRINT)
+  __log_level = log_level;
+#endif
+}
+
 /******************************************************************************/
 int Polaris_Authenticate(PolarisContext_t* context, const char* api_key,
                          const char* unique_id) {
@@ -380,7 +380,7 @@ int Polaris_SendECEFPosition(PolarisContext_t* context, double x_m, double y_m,
       "Sending ECEF position. [size=%u B, position=[%.2f, %.2f, %.2f]]\n",
       (unsigned)message_size, x_m, y_m, z_m);
 #endif
-  PrintData(context->send_buffer, message_size);
+  P1_PrintData(context->send_buffer, message_size);
 
 #ifdef POLARIS_USE_TLS
   int ret = SSL_write(context->ssl, context->send_buffer, message_size);
@@ -423,7 +423,7 @@ int Polaris_SendLLAPosition(PolarisContext_t* context, double latitude_deg,
       "Sending LLA position. [size=%u B, position=[%.6f, %.6f, %.2f]]\n",
       (unsigned)message_size, latitude_deg, longitude_deg, altitude_m);
 #endif
-  PrintData(context->send_buffer, message_size);
+  P1_PrintData(context->send_buffer, message_size);
 
 #ifdef POLARIS_USE_TLS
   int ret = SSL_write(context->ssl, context->send_buffer, message_size);
@@ -454,7 +454,7 @@ int Polaris_RequestBeacon(PolarisContext_t* context, const char* beacon_id) {
 
   P1_DebugPrint("Sending beacon request. [size=%u B, beacon='%s']\n",
               (unsigned)message_size, beacon_id);
-  PrintData(context->send_buffer, message_size);
+  P1_PrintData(context->send_buffer, message_size);
 
 #ifdef POLARIS_USE_TLS
   int ret = SSL_write(context->ssl, context->send_buffer, message_size);
@@ -860,9 +860,34 @@ static int GetHTTPResponse(PolarisContext_t* context) {
 }
 
 /******************************************************************************/
-#ifdef POLARIS_USE_TLS
+#if !defined(P1_NO_PRINT)
+void P1_PrintData(const uint8_t* buffer, size_t length) {
+  if (__log_level < POLARIS_LOG_LEVEL_TRACE) {
+    return;
+  }
+
+  for (size_t i = 0; i < length; ++i) {
+    if (i % 16 != 0) {
+      P1_fprintf(stderr, " ");
+    }
+
+    P1_fprintf(stderr, "%02x", buffer[i]);
+
+    if (i % 16 == 15) {
+      P1_fprintf(stderr, "\n");
+    }
+  }
+  P1_fprintf(stderr, "\n");
+}
+#endif
+
+/******************************************************************************/
+#if !defined(P1_NO_PRINT) && defined(POLARIS_USE_TLS)
 void ShowCerts(SSL* ssl) {
-  #if defined(POLARIS_DEBUG) || defined(POLARIS_TRACE)
+  if (__log_level >= POLARIS_LOG_LEVEL_DEBUG) {
+    return;
+  }
+
   X509* cert = SSL_get_peer_certificate(ssl);
   if (cert != NULL) {
     char* line;
@@ -874,6 +899,5 @@ void ShowCerts(SSL* ssl) {
   } else {
     P1_DebugPrint("No client certificates configured.\n");
   }
-  #endif
 }
 #endif

c/src/point_one/polaris/polaris.h

@@ -69,6 +69,10 @@
 # define POLARIS_SEND_TIMEOUT_MS 1000
 #endif
 
+/**
+ * @name Polaris Return Codes
+ * @{
+ */
 #define POLARIS_SUCCESS 0
 #define POLARIS_ERROR -1
 #define POLARIS_NOT_ENOUGH_SPACE -2
@@ -78,6 +82,16 @@
 #define POLARIS_FORBIDDEN -6
 #define POLARIS_CONNECTION_CLOSED -7
 #define POLARIS_TIMED_OUT -8
+/** @} */
+
+/**
+ * @name Polaris Logging Verbosity Levels
+ * @{
+ */
+#define POLARIS_LOG_LEVEL_INFO 0
+#define POLARIS_LOG_LEVEL_DEBUG 1
+#define POLARIS_LOG_LEVEL_TRACE 2
+/** @} */
 
 struct PolarisContext_s;
 typedef struct PolarisContext_s PolarisContext_t;
@@ -131,6 +145,13 @@ int Polaris_Init(PolarisContext_t* context);
  */
 void Polaris_Free(PolarisContext_t* context);
 
+/**
+ * @brief Set the Polaris library print verbosity level.
+ *
+ * @param log_level The desired verbosity level.
+ */
+void Polaris_SetLogLevel(int log_level);
+
 /**
  * @brief Authenticate with Polaris.
  *

src/point_one/polaris/polaris_client.cc

@@ -60,6 +60,14 @@ PolarisClient::PolarisClient(const std::string& api_key,
     : max_reconnect_attempts_(max_reconnect_attempts),
       api_key_(api_key),
       unique_id_(unique_id) {
+  // Note that the C library print level will not change if the VLOG level is
+  // changed dynamically via SetVLOGLevel() at runtime.
+  if (VLOG_IS_ON(1)) {
+    Polaris_SetLogLevel(POLARIS_LOG_LEVEL_DEBUG);
+  } else if (VLOG_IS_ON(2)) {
+    Polaris_SetLogLevel(POLARIS_LOG_LEVEL_TRACE);
+  }
+
   SetPolarisEndpoint();
 
   polaris_.SetRTCMCallback([&](const uint8_t* buffer, size_t size_bytes) {