Integrate StrPrintf utilities into build

This patch provides a header file for the StrPrint functions and
integrates the source file into the build.

Author: tdz

Makefile

@@ -50,6 +50,7 @@ DRIVERLIB = $(SDK_PATH)/driverlib
 OSLIB = $(SDK_PATH)/oslib
 FREERTOS = $(SDK_PATH)/third_party/FreeRTOS
 COMMON = $(SDK_PATH)/example/common
+STR = external/str
 
 CPPFLAGS += $(DEFINES) $(INC)
 CFLAGS += -Os -ffunction-sections -fdata-sections -Wall -std=c11
@@ -63,6 +64,7 @@ INC += -I$(FREERTOS)/source
 INC += -I$(FREERTOS)/source/include
 INC += -I$(FREERTOS)/source/portable/GCC/ARM_CM4
 INC += -I$(COMMON)
+INC += -I$(STR)
 
 LIBS =
 
@@ -124,6 +126,10 @@ OBJ += $(addprefix $(OBJDIR)/$(DRIVERLIB)/, \
 	wdt.o \
 	)
 
+OBJ += $(addprefix $(OBJDIR)/$(STR)/, \
+	StrPrintf.o \
+	)
+
 .PHONY: all
 all: $(TARGET)
 

external/str/StrPrintf.c

@@ -35,7 +35,7 @@
 
 /* ---- Include Files ---------------------------------------------------- */
 
-#include "Str.h"
+#include "StrPrintf.h"
 #include <limits.h>
 #include <string.h>
 

external/str/StrPrintf.h

@@ -0,0 +1,21 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+#pragma once
+
+#include <stdarg.h>
+
+typedef int (*StrXPrintfFunc)(void *outParm, int c);
+
+int
+StrPrintf(char* outStr, int maxLen, const char* fmt, ...);
+
+int
+StrXPrintf(StrXPrintfFunc outFunc, void* outParm, const char* fmt, ...);
+
+int
+vStrPrintf(char* outStr, int maxLen, const char* fmt, va_list args);
+
+int
+vStrXPrintf(StrXPrintfFunc outFunc,void* outParm, const char* fmt,
+            va_list args);