Add missing file, fix bug in aufile_set_position.

rem/aufile/aufile.c

@@ -307,7 +307,7 @@ int aufile_set_position(struct aufile *af, const struct aufile_prm *prm,
 	off_t pos = (off_t)(prm->srate * aufmt_sample_size(prm->fmt)
 		* prm->channels * pos_ms / 1000);
 
-	pos = max((off_t)datasize, pos);
+	pos = min((off_t)datasize, pos);
 
 	if (fseek(af->f, pos, SEEK_CUR) < 0)
 		return errno;

test/aupos.c

@@ -0,0 +1,46 @@
+/**
+ * @file src/aupos.c audio file setposition test
+ *
+ * Copyright (C) 2023 Lars Immisch
+ */
+
+#include <re.h>
+#include <rem.h>
+#include "test.h"
+
+
+#define DEBUG_MODULE "auposition"
+#define DEBUG_LEVEL 5
+#include <re_dbg.h>
+
+
+int test_auposition(void)
+{
+	struct aufile *af = NULL;
+	struct aufile_prm prm;
+	char path[256];
+	uint8_t buffer[128];
+
+	re_snprintf(path, sizeof(path), "%s/beep.wav", test_datapath());
+
+	int err = aufile_open(&af, &prm, path, AUFILE_READ);
+	if (err)
+		TEST_ERR(err);
+
+	err = aufile_set_position(af, &prm, 67);
+	if (err)
+		TEST_ERR(err);
+
+	/* That file is 67 ms long, so we shouldn't read anything */
+	size_t size = sizeof(buffer);
+	err = aufile_read(af, buffer, &size);
+	if (err)
+		TEST_ERR(err);
+
+	TEST_EQUALS(0, size);
+
+out:
+	mem_deref(af);
+
+	return err;
+}