1 files changed, 72 insertions, 0 deletions
diff --git a/prism/internal/source.h b/prism/internal/source.h
new file mode 100644
index 0000000000..b3c2b55be3
--- /dev/null
+++ b/prism/internal/source.h
@@ -0,0 +1,72 @@
+#ifndef PRISM_INTERNAL_SOURCE_H
+#define PRISM_INTERNAL_SOURCE_H
+
+#include "prism/source.h"
+#include "prism/buffer.h"
+
+#include <stdbool.h>
+
+/*
+ * The type of source, which determines cleanup behavior.
+ */
+typedef enum {
+    /* Wraps existing constant memory, no cleanup. */
+    PM_SOURCE_CONSTANT,
+
+    /* Wraps existing shared memory (non-owning slice), no cleanup. */
+    PM_SOURCE_SHARED,
+
+    /* Owns a heap-allocated buffer, freed on cleanup. */
+    PM_SOURCE_OWNED,
+
+    /* Memory-mapped file, unmapped on cleanup. */
+    PM_SOURCE_MAPPED,
+
+    /* Stream source backed by a pm_buffer_t. */
+    PM_SOURCE_STREAM
+} pm_source_type_t;
+
+/*
+ * The internal representation of a source.
+ */
+struct pm_source_t {
+    /* A pointer to the start of the source data. */
+    const uint8_t *source;
+
+    /* The length of the source data in bytes. */
+    size_t length;
+
+    /* The type of the source. */
+    pm_source_type_t type;
+
+    /* Stream-specific data, only used for PM_SOURCE_STREAM sources. */
+    struct {
+        /* The buffer that holds the accumulated stream data. */
+        pm_buffer_t *buffer;
+
+        /* The stream object to read from. */
+        void *stream;
+
+        /* The function to use to read from the stream. */
+        pm_source_stream_fgets_t *fgets;
+
+        /* The function to use to check if the stream is at EOF. */
+        pm_source_stream_feof_t *feof;
+
+        /* Whether the stream has reached EOF. */
+        bool eof;
+    } stream;
+};
+
+/*
+ * Read from a stream into the source's internal buffer. This is used by
+ * pm_parse_stream to incrementally read the source.
+ */
+bool pm_source_stream_read(pm_source_t *source);
+
+/*
+ * Returns whether the stream source has reached EOF.
+ */
+bool pm_source_stream_eof(const pm_source_t *source);
+
+#endif