Allow mongoc_buffer_t larger than INT_MAX

Author: adriandole

src/libmongoc/src/mongoc/mongoc-buffer.c

@@ -31,8 +31,15 @@
 #endif
 
 
-#define SPACE_FOR(_b, _sz) \
-   (((ssize_t) (_b)->datalen - (ssize_t) (_b)->len) >= (ssize_t) (_sz))
+static inline void
+make_space_for (mongoc_buffer_t *buffer, size_t data_size)
+{
+   if (buffer->len + data_size > buffer->datalen) {
+      buffer->datalen = bson_next_power_of_two (buffer->len + data_size);
+      buffer->data = (uint8_t *) buffer->realloc_func (
+         buffer->data, buffer->datalen, buffer->realloc_data);
+   }
+}
 
 
 /**
@@ -135,12 +142,7 @@ _mongoc_buffer_append (mongoc_buffer_t *buffer,
 
    BSON_ASSERT (buffer->datalen);
 
-   if (!SPACE_FOR (buffer, data_size)) {
-      BSON_ASSERT ((buffer->datalen + data_size) < INT_MAX);
-      buffer->datalen = bson_next_power_of_two (data_size + buffer->len);
-      buffer->data =
-         (uint8_t *) buffer->realloc_func (buffer->data, buffer->datalen, NULL);
-   }
+   make_space_for (buffer, data_size);
 
    buf = &buffer->data[buffer->len];
 
@@ -186,12 +188,7 @@ _mongoc_buffer_append_from_stream (mongoc_buffer_t *buffer,
 
    BSON_ASSERT (buffer->datalen);
 
-   if (!SPACE_FOR (buffer, size)) {
-      BSON_ASSERT ((buffer->datalen + size) < INT_MAX);
-      buffer->datalen = bson_next_power_of_two (size + buffer->len);
-      buffer->data =
-         (uint8_t *) buffer->realloc_func (buffer->data, buffer->datalen, NULL);
-   }
+   make_space_for (buffer, size);
 
    buf = &buffer->data[buffer->len];
 
@@ -260,11 +257,7 @@ _mongoc_buffer_fill (mongoc_buffer_t *buffer,
 
    min_bytes -= buffer->len;
 
-   if (!SPACE_FOR (buffer, min_bytes)) {
-      buffer->datalen = bson_next_power_of_two (buffer->len + min_bytes);
-      buffer->data = (uint8_t *) buffer->realloc_func (
-         buffer->data, buffer->datalen, buffer->realloc_data);
-   }
+   make_space_for (buffer, min_bytes);
 
    avail_bytes = buffer->datalen - buffer->len;
 
@@ -341,12 +334,7 @@ _mongoc_buffer_try_append_from_stream (mongoc_buffer_t *buffer,
 
    BSON_ASSERT (buffer->datalen);
 
-   if (!SPACE_FOR (buffer, size)) {
-      BSON_ASSERT ((buffer->datalen + size) < INT_MAX);
-      buffer->datalen = bson_next_power_of_two (size + buffer->len);
-      buffer->data =
-         (uint8_t *) buffer->realloc_func (buffer->data, buffer->datalen, NULL);
-   }
+   make_space_for (buffer, size);
 
    buf = &buffer->data[buffer->len];
 

src/libmongoc/tests/test-mongoc-bulk.c

@@ -5080,6 +5080,49 @@ test_bulk_write_set_client_after_operation (void)
    mongoc_client_destroy (client);
 }
 
+// Test creating a bulk write with more data than INT_MAX.
+static void
+test_bulk_write_more_than_INT_MAX (void)
+{
+   bool ok;
+   bson_error_t error;
+
+   // Create large document.
+   bson_t large_doc = BSON_INITIALIZER;
+   {
+      // Maximum server document size is 16 MiB (16777216).
+      // Subtract 32 for overhead.
+      size_t large_sz = 16777216 - 32;
+      char *large_str = bson_malloc (large_sz);
+      for (size_t i = 0; i < large_sz; i++) {
+         large_str[i] = 'A';
+      }
+      large_str[large_sz] = '\0';
+      BSON_ASSERT (
+         bson_append_utf8 (&large_doc, "key", 3, large_str, large_sz));
+      bson_free (large_str);
+   }
+
+   mongoc_client_t *client = test_framework_new_default_client ();
+   mongoc_collection_t *coll =
+      mongoc_client_get_collection (client, "db", "coll");
+   mongoc_bulk_operation_t *bulk =
+      mongoc_collection_create_bulk_operation_with_opts (coll, NULL /* opts */);
+   size_t added = 0;
+   while (added < (size_t) INT_MAX) {
+      ok = mongoc_bulk_operation_insert_with_opts (
+         bulk, &large_doc, NULL /* opts */, &error);
+      ASSERT_OR_PRINT (ok, error);
+      added += large_doc.len;
+   }
+
+   ok = (bool) mongoc_bulk_operation_execute (bulk, NULL /* reply */, &error);
+   ASSERT_OR_PRINT (ok, error);
+   mongoc_bulk_operation_destroy (bulk);
+   mongoc_collection_destroy (coll);
+   mongoc_client_destroy (client);
+}
+
 void
 test_bulk_install (TestSuite *suite)
 {
@@ -5392,4 +5435,7 @@ test_bulk_install (TestSuite *suite)
    TestSuite_AddLive (suite,
                       "/BulkOperation/set_client_after_operation",
                       test_bulk_write_set_client_after_operation);
+   TestSuite_AddLive (suite,
+                      "/BulkOperation/more_than_INT_MAX",
+                      test_bulk_write_more_than_INT_MAX);
 }