+string
+FileLog::head_and_tail (int amount) const
+{
+ boost::mutex::scoped_lock lm (_mutex);
+
+ uintmax_t head_amount = amount;
+ uintmax_t tail_amount = amount;
+ uintmax_t size = boost::filesystem::file_size (_file);
+
+ if (size < (head_amount + tail_amount)) {
+ head_amount = size;
+ tail_amount = 0;
+ }
+
+ FILE* f = fopen_boost (_file, "r");
+ if (!f) {
+ return "";
+ }
+
+ string out;
+
+ char* buffer = new char[max(head_amount, tail_amount) + 1];
+
+ int N = fread (buffer, 1, head_amount, f);
+ buffer[N] = '\0';
+ out += string (buffer);
+
+ if (tail_amount > 0) {
+ out += "\n .\n .\n .\n";
+
+ fseek (f, - tail_amount - 1, SEEK_END);
+
+ N = fread (buffer, 1, tail_amount, f);
+ buffer[N] = '\0';
+ out += string (buffer) + "\n";
+ }
+
+ delete[] buffer;
+ fclose (f);
+
+ return out;
+}