native/backtrace: improve its print capabilitys and test

cpu/native/backtrace/backtrace.c

@@ -16,20 +16,44 @@
 #include <execinfo.h>
 #include <stddef.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #include "backtrace.h"
 
 void backtrace_print(void)
 {
     void *array[BACKTRACE_SIZE + 1];
-    size_t size;
+    int size;
 
     size = backtrace(array, BACKTRACE_SIZE + 1);
 
     /* skip above line's return address and start with 1 */
-    for (size_t i = 1; i < size; i++) {
+    for (int i = 1; i < size; i++) {
         printf("%p\n", array[i]);
     }
 }
 
+void backtrace_print_symbols(void)
+{
+    void *array[BACKTRACE_SIZE + 1];
+    int size;
+
+    size = backtrace(array, BACKTRACE_SIZE + 1);
+
+    char ** symbols = backtrace_symbols(array , size);
+
+    /* skip above line's return address and start with 1 */
+    for (int i = 1; i < size; i++) {
+        printf("%s\n", symbols[i]);
+    }
+    free(symbols);
+}
+
+int backtrace_len(void)
+{
+    void *array[BACKTRACE_SIZE + 1];
+
+    return backtrace(array, BACKTRACE_SIZE + 1) - 1;
+}
+
 /** @} */

cpu/native/include/backtrace.h

@@ -36,11 +36,23 @@ extern "C" {
 #endif
 
 /**
- * @brief   Print the last @ref BACKTRACE_SIZE return addresses from call of this
+ * @brief   Print up to the last @ref BACKTRACE_SIZE return addresses from call of this
  *          function
  */
 void backtrace_print(void);
 
+/**
+ * @brief   Print up to the last @ref BACKTRACE_SIZE symbol_names from call of this
+ *          function
+ */
+void backtrace_print_symbols(void);
+
+/**
+ * @brief   get the number of stack frames that are printed by print or print_symbols
+ *
+ */
+int backtrace_len(void);
+
 #ifdef __cplusplus
 }
 #endif

tests/cpu/native_backtrace/main.c

@@ -24,7 +24,8 @@
 
 int main(void)
 {
-    printf("BACKTRACE_SIZE: %u\n", BACKTRACE_SIZE);
+    printf("BACKTRACE_SIZE: %d\n", backtrace_len());
     backtrace_print();
+    backtrace_print_symbols();
     return 0;
 }

tests/cpu/native_backtrace/tests/01-run.py

@@ -15,6 +15,8 @@ def testfunc(child):
     trace_size = int(child.match.group(1))
     for i in range(trace_size):
         child.expect(r"0x[0-9a-f]+")
+    for i in range(trace_size):
+        child.expect(r".*")
 
     print("All tests successful")