Simplify input stream API

More or less the same rationale as the previous commit, but for reading.  This
makes for nice symmetry with writing, at the cost of a slightly more annoying
reader interface since the source doesn't know its block size or name.

1 files changed, 26 insertions, 30 deletions

diff --git a/src/byte_source.h b/src/byte_source.h
index d054e156..2bd06bdf 100644
--- a/src/byte_source.h
+++ b/src/byte_source.h
@@ -1,5 +1,5 @@
 /*
-  Copyright 2011-2020 David Robillard <d@drobilla.net>
+  Copyright 2011-2021 David Robillard <d@drobilla.net>
 
   Permission to use, copy, modify, and/or distribute this software for any
   purpose with or without fee is hereby granted, provided that the above
@@ -26,29 +26,27 @@
 #include <stddef.h>
 #include <stdint.h>
 
-typedef enum {
-  FROM_STRING,   ///< Reading from a user-provided buffer
-  FROM_FILENAME, ///< Reading from a file we opened
-  FROM_FUNCTION, ///< Reading from a user-provided function
-} SerdByteSourceType;
-
-struct SerdByteSourceImpl {
-  SerdReadFunc        read_func;  ///< Read function (e.g. fread)
-  SerdStreamErrorFunc error_func; ///< Error function (e.g. ferror)
-  SerdStreamCloseFunc close_func; ///< Function for closing stream
-  void*               stream;     ///< Stream (e.g. FILE)
-  size_t              page_size;  ///< Number of bytes to read at a time
-  size_t              buf_size;   ///< Number of bytes in file_buf
-  SerdNode*           name;       ///< Name of stream (referenced by cur)
-  SerdCaret           caret;      ///< File position for error reporting
-  uint8_t*            file_buf;   ///< Buffer iff reading pages from a file
-  const uint8_t*      read_buf;   ///< Pointer to file_buf or read_byte
-  size_t              read_head;  ///< Offset into read_buf
-  SerdByteSourceType  type;       ///< Type of input
-  uint8_t             read_byte;  ///< 1-byte 'buffer' used when not paging
-  bool                prepared;   ///< True iff prepared for reading
-  bool                eof;        ///< True iff end of file reached
-};
+typedef struct {
+  SerdInputStream* in;         ///< Input stream to read from
+  size_t           block_size; ///< Number of bytes to read at a time
+  size_t           buf_size;   ///< Number of bytes in block
+  SerdNode*        name;       ///< Name of stream (for caret)
+  SerdCaret        caret;      ///< File position for error reporting
+  uint8_t*         block;      ///< Buffer if reading blocks
+  const uint8_t*   read_buf;   ///< Pointer to block or read_byte
+  size_t           read_head;  ///< Offset into read_buf
+  uint8_t          read_byte;  ///< 1-byte 'buffer' if reading bytes
+  bool             prepared;   ///< True iff prepared for reading
+  bool             eof;        ///< True iff end of file reached
+} SerdByteSource;
+
+SerdByteSource*
+serd_byte_source_new_input(SerdInputStream* input,
+                           const SerdNode*  name,
+                           size_t           block_size);
+
+void
+serd_byte_source_free(SerdByteSource* source);
 
 SerdStatus
 serd_byte_source_prepare(SerdByteSource* source);
@@ -71,6 +69,8 @@ serd_byte_source_advance(SerdByteSource* source)
   const bool was_eof = source->eof;
 
   switch (serd_byte_source_peek(source)) {
+  case '\0':
+    break;
   case '\n':
     ++source->caret.line;
     source->caret.col = 0;
@@ -79,12 +79,8 @@ serd_byte_source_advance(SerdByteSource* source)
     ++source->caret.col;
   }
 
-  if (source->type != FROM_STRING) {
-    if (++source->read_head >= source->buf_size) {
-      st = serd_byte_source_page(source);
-    }
-  } else if (!source->eof) {
-    source->eof = source->read_buf[++source->read_head] == '\0';
+  if (++source->read_head >= source->buf_size) {
+    st = serd_byte_source_page(source);
   }
 
   return (was_eof && source->eof) ? SERD_FAILURE : st;