Be a little more careful to handle exceptions from boost::filesystem::file_size

[dcpomatic.git] / src / lib / file_log.cc

diff --git a/src/lib/file_log.cc b/src/lib/file_log.cc
index b9aa84c3d9ff2aa957f84f01714fb1cbc1def2f9..4d6a0e6ea39fd67b7b13ea40fc7a7f475a227826 100644 (file)
--- a/src/lib/file_log.cc
+++ b/src/lib/file_log.cc
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2012 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2021 Carl Hetherington <cth@carlh.net>
 
     This file is part of DCP-o-matic.
 
@@ -18,6 +18,7 @@
 
 */
 
+
 #include "file_log.h"
 #include "cross.h"
 #include "config.h"
@@ -25,10 +26,12 @@
 #include <iostream>
 #include <cerrno>
 
+
 using std::cout;
 using std::string;
 using std::max;
-using boost::shared_ptr;
+using std::shared_ptr;
+
 
 /** @param file Filename to write log to */
 FileLog::FileLog (boost::filesystem::path file)
@@ -37,25 +40,28 @@ FileLog::FileLog (boost::filesystem::path file)
        set_types (Config::instance()->log_types());
 }
 
+
 FileLog::FileLog (boost::filesystem::path file, int types)
        : _file (file)
 {
        set_types (types);
 }
 
+
 void
 FileLog::do_log (shared_ptr<const LogEntry> entry)
 {
-       FILE* f = fopen_boost (_file, "a");
+       auto f = fopen_boost (_file, "a");
        if (!f) {
                cout << "(could not log to " << _file.string() << " error " << errno << "): " << entry->get() << "\n";
                return;
        }
 
-       fprintf (f, "%s\n", entry->get().c_str ());
+       fprintf (f, "%s\n", entry->get().c_str());
        fclose (f);
 }
 
+
 string
 FileLog::head_and_tail (int amount) const
 {
@@ -63,21 +69,25 @@ FileLog::head_and_tail (int amount) const
 
        uintmax_t head_amount = amount;
        uintmax_t tail_amount = amount;
-       uintmax_t size = boost::filesystem::file_size (_file);
+       boost::system::error_code ec;
+       uintmax_t size = boost::filesystem::file_size (_file, ec);
+       if (size == static_cast<uintmax_t>(-1)) {
+               return "";
+       }
 
        if (size < (head_amount + tail_amount)) {
                head_amount = size;
                tail_amount = 0;
        }
 
-       FILE* f = fopen_boost (_file, "r");
+       auto f = fopen_boost (_file, "r");
        if (!f) {
                return "";
        }
 
        string out;
 
-       char* buffer = new char[max(head_amount, tail_amount) + 1];
+       auto buffer = new char[max(head_amount, tail_amount) + 1];
 
        int N = fread (buffer, 1, head_amount, f);
        buffer[N] = '\0';