Add assertions for all non-null pointers in the public API

Clang issues warnings at build time based on the SERD_NONNULL annotations,
which is a much better approach in general.  However, it does not cover cases
where the API is being used with another compiler, or without a compiler that
can statically check things at all (such as Python or other dynamic language
bindings).

In those situations, getting a clear assertion message is a lot less confusing
than a random crash somewhere in serd, and it makes it clear that the bug is in
the caller, so I think it's worth the tedious verbosity.

1 files changed, 18 insertions, 0 deletions

diff --git a/src/writer.c b/src/writer.c
index 5416d144..e73533e7 100644
--- a/src/writer.c
+++ b/src/writer.c
@@ -1268,6 +1268,8 @@ serd_writer_write_node(SerdWriter* writer, const SerdNode* node)
 SerdStatus
 serd_writer_finish(SerdWriter* writer)
 {
+  assert(writer);
+
   SerdStatus st = SERD_SUCCESS;
   if (ctx(writer, SERD_SUBJECT)) {
     st = write_sep(writer, writer->context.flags, SEP_END_S);
@@ -1296,6 +1298,10 @@ serd_writer_new(SerdWorld*      world,
                 const SerdEnv*  env,
                 SerdByteSink*   byte_sink)
 {
+  assert(world);
+  assert(env);
+  assert(byte_sink);
+
   const WriteContext context = WRITE_CONTEXT_NULL;
   SerdWriter*        writer  = (SerdWriter*)calloc(1, sizeof(SerdWriter));
 
@@ -1321,6 +1327,8 @@ serd_writer_new(SerdWorld*      world,
 void
 serd_writer_chop_blank_prefix(SerdWriter* writer, const char* prefix)
 {
+  assert(writer);
+
   free(writer->bprefix);
   writer->bprefix_len = 0;
   writer->bprefix     = NULL;
@@ -1336,6 +1344,8 @@ serd_writer_chop_blank_prefix(SerdWriter* writer, const char* prefix)
 SerdStatus
 serd_writer_set_base_uri(SerdWriter* writer, const SerdNode* uri)
 {
+  assert(writer);
+
   if (uri->type != SERD_URI) {
     return SERD_ERR_BAD_ARG;
   }
@@ -1362,6 +1372,8 @@ serd_writer_set_base_uri(SerdWriter* writer, const SerdNode* uri)
 SerdStatus
 serd_writer_set_root_uri(SerdWriter* writer, const SerdNode* uri)
 {
+  assert(writer);
+
   serd_node_free(writer->root_node);
   writer->root_node = NULL;
   writer->root_uri  = SERD_URI_NULL;
@@ -1421,6 +1433,7 @@ serd_writer_free(SerdWriter* writer)
 const SerdSink*
 serd_writer_sink(SerdWriter* writer)
 {
+  assert(writer);
   return &writer->iface;
 }
 
@@ -1430,7 +1443,10 @@ serd_buffer_sink(const void* const buf,
                  const size_t      nmemb,
                  void* const       stream)
 {
+  assert(buf);
   assert(size == 1);
+  assert(stream);
+
   (void)size;
 
   SerdBuffer* buffer = (SerdBuffer*)stream;
@@ -1443,6 +1459,8 @@ serd_buffer_sink(const void* const buf,
 char*
 serd_buffer_sink_finish(SerdBuffer* const stream)
 {
+  assert(stream);
+
   serd_buffer_sink("", 1, 1, stream);
   return (char*)stream->buf;
 }