don't leak memory when throwing an exception

src/text_file_reader.cpp

@@ -48,6 +48,7 @@ TextFileReader::TextFileReader(const std::string &filename, const std::string &f
   fp = fopen(filename.c_str(), "r");
 
   if (fp == nullptr) {
+    delete[] line;
     throw FileReaderException(
         fmt::format("cannot open {} file {}: {}", filetype, filename, utils::getsyserror()));
   }
@@ -74,7 +75,11 @@ TextFileReader::TextFileReader(FILE *fp, std::string filetype) :
     filetype(std::move(filetype)), closefp(false), line(nullptr), fp(fp), ignore_comments(true)
 {
   set_bufsize(1024);
-  if (fp == nullptr) throw FileReaderException("Invalid file descriptor");
+  if (fp == nullptr) {
+    delete[] line;
+    line = nullptr;
+    throw FileReaderException("Invalid file descriptor");
+  }
 }
 
 /** Closes the file */
@@ -90,6 +95,8 @@ TextFileReader::~TextFileReader()
 void TextFileReader::set_bufsize(int newsize)
 {
   if (newsize < 100) {
+    delete[] line;
+    line = nullptr;
     throw FileReaderException(
         fmt::format("line buffer size {} for {} file too small, must be > 100", newsize, filetype));
   }
@@ -112,6 +119,8 @@ void TextFileReader::skip_line()
   char *ptr = fgets(line, bufsize, fp);
   if (ptr == nullptr) {
     // EOF
+    delete[] line;
+    line = nullptr;
     throw EOFException(fmt::format("Missing line in {} file!", filetype));
   }
 }

unittest/commands/test_groups.cpp

@@ -229,6 +229,7 @@ TEST_F(GroupTest, SelectRestart)
                  command("group five subtract all half xxx"););
     TEST_FAILURE(".*ERROR: Group ID xxx does not exist.*",
                  command("group five intersect half top xxx"););
+    delete[] flags;
 }
 
 TEST_F(GroupTest, Molecular)

unittest/formats/test_file_operations.cpp

@@ -232,6 +232,7 @@ TEST_F(FileOperationsTest, read_lines_from_file)
     rv = utils::read_lines_from_file(fp, 2, MAX_BUF_SIZE / 2, buf, me, world);
     ASSERT_EQ(rv, 1);
     delete[] buf;
+    if (me == 0) fclose(fp);
 }
 
 TEST_F(FileOperationsTest, logmesg)

unittest/formats/test_text_file_reader.cpp

@@ -87,6 +87,16 @@ TEST_F(TextFileReaderTest, nofp)
     ASSERT_THROW({ TextFileReader reader(nullptr, "test"); }, FileReaderException);
 }
 
+TEST_F(TextFileReaderTest, buffer)
+{
+    test_files();
+    auto *reader = new TextFileReader("text_reader_two.file", "test");
+    reader->set_bufsize(4096);
+    auto *line   = reader->next_line();
+    ASSERT_THROW({ reader->set_bufsize(20); }, FileReaderException);
+    delete reader;
+}
+
 TEST_F(TextFileReaderTest, usefp)
 {
     test_files();