Refactor next_line to return timeout indicator

libvast/src/format/csv.cpp

@@ -410,13 +410,14 @@ caf::error reader::read_impl(size_t max_events, size_t max_slice_size,
                              consumer& callback) {
   VAST_ASSERT(max_events > 0);
   VAST_ASSERT(max_slice_size > 0);
-  bool timeout = false;
   auto next_line = [&] {
-    if (!builder_ || builder_->rows() == 0)
+    if (!builder_ || builder_->rows() == 0) {
       lines_->next();
-    else
-      timeout = lines_->next_timeout(
+      return false;
+    } else {
+      return lines_->next_timeout(
         vast::defaults::import::shared::partial_slice_read_timeout);
+    }
   };
   if (!parser_) {
     auto p = read_header(lines_->get());
@@ -425,8 +426,8 @@ caf::error reader::read_impl(size_t max_events, size_t max_slice_size,
     parser_ = *std::move(p);
   }
   auto& p = *parser_;
-  next_line();
-  for (size_t produced = 0; produced < max_events; next_line()) {
+  bool timeout = next_line();
+  for (size_t produced = 0; produced < max_events; timeout = next_line()) {
     if (timeout) {
       VAST_DEBUG(this, "reached input timeout at line", lines_->line_number());
       return finish(callback);

libvast/src/format/syslog.cpp

@@ -98,13 +98,15 @@ reader::read_impl(size_t max_events, size_t max_slice_size, consumer& f) {
   bool timeout = false;
   table_slice_builder_ptr bptr = nullptr;
   auto next_line = [&] {
-    if (!bptr || bptr->rows() == 0)
+    if (!bptr || bptr->rows() == 0) {
       lines_->next();
-    else
-      timeout = lines_->next_timeout(
+      return false;
+    } else {
+      return lines_->next_timeout(
         vast::defaults::import::shared::partial_slice_read_timeout);
+    }
   };
-  for (size_t produced = 0; produced < max_events; next_line()) {
+  for (size_t produced = 0; produced < max_events; timeout = next_line()) {
     if (timeout) {
       VAST_DEBUG(this, "reached input timeout at line", lines_->line_number());
       return finish(f);

libvast/vast/format/json.hpp

@@ -159,13 +159,15 @@ caf::error reader<Selector>::read_impl(size_t max_events, size_t max_slice_size,
   table_slice_builder_ptr bptr = nullptr;
   bool timeout = false;
   auto next_line = [&] {
-    if (!bptr || bptr->rows() == 0)
+    if (!bptr || bptr->rows() == 0) {
       lines_->next();
-    else
-      timeout = lines_->next_timeout(
+      return false;
+    } else {
+      return lines_->next_timeout(
         vast::defaults::import::shared::partial_slice_read_timeout);
+    }
   };
-  for (; produced < max_events; next_line()) {
+  for (; produced < max_events; timeout = next_line()) {
     if (timeout) {
       VAST_DEBUG(this, "reached input timeout at line", lines_->line_number());
       return finish(cons);