enb,s1ap: print filename when writing S1AP PCAP

lib/include/srsran/common/s1ap_pcap.h

@@ -14,25 +14,23 @@
 #define SRSRAN_S1AP_PCAP_H
 
 #include "srsran/common/pcap.h"
+#include <string>
 
 namespace srsran {
 
 class s1ap_pcap
 {
 public:
-  s1ap_pcap()
-  {
-    enable_write = false;
-    pcap_file    = NULL;
-  }
+  s1ap_pcap() = default;
   void enable();
-  void open(const char* filename);
+  void open(const char* filename_);
   void close();
   void write_s1ap(uint8_t* pdu, uint32_t pdu_len_bytes);
 
 private:
-  bool  enable_write;
-  FILE* pcap_file;
+  bool        enable_write = false;
+  std::string filename;
+  FILE*       pcap_file = nullptr;
 };
 
 } // namespace srsran

lib/src/common/s1ap_pcap.cc

@@ -21,14 +21,15 @@ void s1ap_pcap::enable()
 {
   enable_write = true;
 }
-void s1ap_pcap::open(const char* filename)
+void s1ap_pcap::open(const char* filename_)
 {
-  pcap_file    = DLT_PCAP_Open(S1AP_LTE_DLT, filename);
+  filename     = filename_;
+  pcap_file    = DLT_PCAP_Open(S1AP_LTE_DLT, filename.c_str());
   enable_write = true;
 }
 void s1ap_pcap::close()
 {
-  fprintf(stdout, "Saving S1AP PCAP file\n");
+  fprintf(stdout, "Saving S1AP PCAP file (DLT=%d) to %s\n", S1AP_LTE_DLT, filename.c_str());
   DLT_PCAP_Close(pcap_file);
 }