Add QUtil::read_file_into_memory

This code was essentially duplicated between test_driver and
standalone_fuzz_target_runner.

1 files changed, 39 insertions, 0 deletions

diff --git a/libqpdf/QUtil.cc b/libqpdf/QUtil.cc
index ddfc0cdb..151832fb 100644
--- a/libqpdf/QUtil.cc
+++ b/libqpdf/QUtil.cc
@@ -957,6 +957,45 @@ QUtil::read_lines_from_file(char const* filename)
     return lines;
 }
 
+void
+QUtil::read_file_into_memory(
+    char const* filename,
+    PointerHolder<char>& file_buf, size_t& size)
+{
+    FILE* f = safe_fopen(filename, "rb");
+    fseek(f, 0, SEEK_END);
+    size = QIntC::to_size(QUtil::tell(f));
+    fseek(f, 0, SEEK_SET);
+    file_buf = PointerHolder<char>(true, new char[size]);
+    char* buf_p = file_buf.getPointer();
+    size_t bytes_read = 0;
+    size_t len = 0;
+    while ((len = fread(buf_p + bytes_read, 1, size - bytes_read, f)) > 0)
+    {
+        bytes_read += len;
+    }
+    if (bytes_read != size)
+    {
+        if (ferror(f))
+        {
+            throw std::runtime_error(
+                std::string("failure reading file ") + filename +
+                " into memory: read " +
+                uint_to_string(bytes_read) + "; wanted " +
+                uint_to_string(size));
+        }
+        else
+        {
+            throw std::runtime_error(
+                std::string("premature eof reading file ") + filename +
+                " into memory: read " +
+                uint_to_string(bytes_read) + "; wanted " +
+                uint_to_string(size));
+        }
+    }
+    fclose(f);
+}
+
 std::list<std::string>
 QUtil::read_lines_from_file(std::istream& in)
 {