Merge pull request #844 from greenbone/GEA-635_Use_compression_in_fee…

…d_updates

Add: Added a function that opens a gzip file for reading via a file descriptor.

util/compressutils.c

@@ -304,3 +304,35 @@ gvm_gzip_open_file_reader (const char *path)
   FILE *file = fopencookie (gz_file, "r", io_functions);
   return file;
 }
+
+/**
+ * @brief Opens a gzip file as a FILE* stream for reading and decompression.
+ *
+ * @param[in]  fd  File descriptor of the gzip file to open.
+ *
+ * @return The FILE* on success, NULL otherwise.
+ */
+FILE *
+gvm_gzip_open_file_reader_fd (int fd)
+{
+  static cookie_io_functions_t io_functions = {
+    .read = gz_file_read,
+    .write = NULL,
+    .seek = NULL,
+    .close = gz_file_close,
+  };
+
+  if (fd < 0)
+    {
+      return NULL;
+    }
+
+  gzFile gz_file = gzdopen (fd, "r");
+  if (gz_file == NULL)
+    {
+      return NULL;
+    }
+
+  FILE *file = fopencookie (gz_file, "r", io_functions);
+  return file;
+}

util/compressutils.h

@@ -25,4 +25,7 @@ gvm_uncompress (const void *, unsigned long, unsigned long *);
 FILE *
 gvm_gzip_open_file_reader (const char *);
 
+FILE *
+gvm_gzip_open_file_reader_fd (int);
+
 #endif /* not _GVM_COMPRESSUTILS_H */

util/compressutils_tests.c

@@ -7,6 +7,7 @@
 
 #include <cgreen/cgreen.h>
 #include <cgreen/mocks.h>
+#include <fcntl.h>
 
 Describe (compressutils);
 BeforeEach (compressutils)
@@ -79,6 +80,30 @@ Ensure (compressutils, can_uncompress_using_reader)
   assert_that (fclose (stream), is_equal_to (0));
 }
 
+Ensure (compressutils, can_uncompress_using_fd_reader)
+{
+  const char *testdata = "TEST-12345-12345-TEST";
+  size_t compressed_len;
+  char *compressed =
+    gvm_compress_gzipheader (testdata, strlen (testdata) + 1, &compressed_len);
+
+  char compressed_filename[35] = "/tmp/gvm_gzip_test_XXXXXX";
+  int compressed_fd = mkstemp (compressed_filename);
+  write (compressed_fd, compressed, compressed_len);
+  close (compressed_fd);
+
+  compressed_fd = open (compressed_filename, O_RDONLY);
+
+  FILE *stream = gvm_gzip_open_file_reader_fd (compressed_fd);
+  assert_that (stream, is_not_null);
+
+  gchar *uncompressed = g_malloc0 (30);
+  fread (uncompressed, 1, 30, stream);
+  assert_that (uncompressed, is_equal_to_string (testdata));
+
+  assert_that (fclose (stream), is_equal_to (0));
+}
+
 /* Test suite. */
 int
 main (int argc, char **argv)
@@ -92,9 +117,10 @@ main (int argc, char **argv)
   add_test_with_context (suite, compressutils,
                          can_compress_and_uncompress_with_header);
   add_test_with_context (suite, compressutils, can_uncompress_using_reader);
+  add_test_with_context (suite, compressutils, can_uncompress_using_fd_reader);
 
   if (argc > 1)
     return run_single_test (suite, argv[1], create_text_reporter ());
 
   return run_test_suite (suite, create_text_reporter ());
-}
+}