1 files changed, 23 insertions, 20 deletions

diff --git a/src/byte_source.h b/src/byte_source.h
index 5ae40acb..9e65ef75 100644
--- a/src/byte_source.h
+++ b/src/byte_source.h
@@ -15,8 +15,8 @@
 
 #include <assert.h>
 #include <stdbool.h>
-#include <stddef.h>
 #include <stdint.h>
+#include <stdio.h>
 
 typedef struct {
   SerdInputStream* in;         ///< Input stream to read from
@@ -32,14 +32,15 @@ typedef struct {
   bool             eof;        ///< True iff end of file reached
 } SerdByteSource;
 
-SerdByteSource*
-serd_byte_source_new_input(ZixAllocator*    allocator,
-                           SerdInputStream* input,
-                           const SerdNode*  name,
-                           size_t           block_size);
+SerdStatus
+serd_byte_source_init(ZixAllocator*    allocator,
+                      SerdByteSource*  source,
+                      SerdInputStream* input,
+                      const SerdNode*  name,
+                      size_t           block_size);
 
 void
-serd_byte_source_free(ZixAllocator* allocator, SerdByteSource* source);
+serd_byte_source_destroy(ZixAllocator* allocator, SerdByteSource* source);
 
 SerdStatus
 serd_byte_source_prepare(SerdByteSource* source);
@@ -50,35 +51,37 @@ serd_byte_source_page(SerdByteSource* source);
 SerdStatus
 serd_byte_source_skip_bom(SerdByteSource* source);
 
-ZIX_PURE_FUNC static inline uint8_t
-serd_byte_source_peek(SerdByteSource* source)
+ZIX_PURE_FUNC static inline int
+serd_byte_source_peek(const SerdByteSource* const source)
 {
   assert(source->prepared);
-  return source->read_buf[source->read_head];
+
+  return source->eof ? EOF : (int)source->read_buf[source->read_head];
 }
 
 static inline SerdStatus
-serd_byte_source_advance(SerdByteSource* source)
+serd_byte_source_advance_past(SerdByteSource* const source, const int current)
 {
-  SerdStatus st      = SERD_SUCCESS;
-  const bool was_eof = source->eof;
+  /* Reading the buffer here can be an expensive cache miss, so we only assert
+     that the passed current character is correct in debug builds.  In release
+     builds, this function only accesses the `source` structure, unless a page
+     read needs to happen. */
+
+  assert(current == serd_byte_source_peek(source));
 
-  switch (serd_byte_source_peek(source)) {
-  case '\0':
-    break;
-  case '\n':
+  if (current == '\n') {
     ++source->caret.line;
     source->caret.col = 0;
-    break;
-  default:
+  } else {
     ++source->caret.col;
   }
 
+  SerdStatus st = SERD_SUCCESS;
   if (++source->read_head >= source->buf_size) {
     st = serd_byte_source_page(source);
   }
 
-  return (was_eof && source->eof) ? SERD_FAILURE : st;
+  return st;
 }
 
 #endif // SERD_SRC_BYTE_SOURCE_H