Give the fcore ptr a type

src/tus_file.c

@@ -162,6 +162,7 @@ tus_file_final_concat(struct VPFX(tus_server) *srv,
 		pdisk = part->disk;
 		AN(pdisk);
 		if (part->ptr != NULL) {
+			assert(TFCP_READABLE(part->ptr_type));
 			length += pdisk->upload_length;
 			continue;
 		}
@@ -175,6 +176,7 @@ tus_file_final_concat(struct VPFX(tus_server) *srv,
 		AZ(pthread_mutex_unlock(&part->mtx));
 		if (part->ptr == NULL)
 			goto err;
+		assert(TFCP_READABLE(part->ptr_type));
 		length += pdisk->upload_length;
 	}
 
@@ -218,10 +220,12 @@ tus_file_final_birth(struct tus_file_core **fcorep,
 	fdisk = fcore->disk;
 	CHECK_OBJ_NOTNULL(fdisk, VMOD_TUS_FILE_DISK_MAGIC);
 
+	assert(fcore->ptr_type == TFCP_INVALID);
 	AZ(fcore->ptr);
 	AZ(fcore->len);
 	fcore->ptr = embryo->concat;
 	fcore->len = embryo->concat_l;
+	fcore->ptr_type = TFCP_CONCAT;
 	fdisk->upload_length = fdisk->upload_offset = embryo->upload_length;
 	vsb = embryo->spec_vsb;
 
@@ -262,8 +266,10 @@ tus_file_final_fini(struct tus_file_core *fcore)
 	if (fcore->ptr == NULL)
 		return;
 
+	assert(fcore->ptr_type == TFCP_CONCAT);
 	CAST_OBJ_NOTNULL(concat, fcore->ptr, TUS_CONCAT_MAGIC);
 	fcore->ptr = NULL;
+	fcore->ptr_type == TFCP_INVALID;
 	assert (fcore->len >= sizeof *concat);
 	fcore->len = 0;
 
@@ -294,6 +300,7 @@ tus_concat_hash(VRT_CTX, const struct VPFX(tus_server) *srv,
 		part = concat->cores[i];
 		if (part->len == 0)
 			continue;
+		assert(TFCP_READABLE(part->ptr_type));
 		AN(part->ptr);
 		tus_chksum_update(ctx, c, part->ptr, part->len);
 	}
@@ -315,6 +322,7 @@ tus_file_final_urls(VRT_CTX, const struct tus_file_core *fcore, const char *pfx)
 
 	WS_VSB_new(vsb, ctx->ws);
 	VSB_cat(vsb, "final;");
+	assert(fcore->ptr_type == TFCP_CONCAT);
 	CAST_OBJ_NOTNULL(concat, fcore->ptr, TUS_CONCAT_MAGIC);
 	for (i = 0; i < concat->n; i++) {
 		part = concat->cores[i];
@@ -420,12 +428,14 @@ tus_file_mmap(struct tus_file_core *fcore)
 	CHECK_TUS_FILE_DISK(fdisk);
 
 	assert(fdisk->upload_length == fdisk->upload_offset);
+	assert(fcore->ptr_type == TFCP_INVALID);
 	AZ(fcore->ptr);
 	AZ(fcore->len);
 
 	fcore->ptr = mmap(NULL, fdisk->upload_length, PROT_READ,
 	    MAP_SHARED | MAP_NORESERVE, fcore->fd, header_size);
 	AN(fcore->ptr);
+	fcore->ptr_type = TFCP_MMAP_RO;
 	tus_file_close(fcore);
 	fcore->len = fdisk->upload_length;
 }
@@ -467,6 +477,7 @@ tus_file_fini(struct tus_file_core *fcore)
 	if (fdisk->type == TUS_FINAL) {
 		tus_file_final_fini(fcore);
 	} else if (fcore->ptr != NULL) {
+		fcore->ptr_type = TFCP_INVALID;
 		(void) munmap(fcore->ptr, fcore->len);
 		fcore->ptr = NULL;
 		fcore->len = 0;

src/tus_file.h

@@ -65,6 +65,16 @@ struct tus_file_disk {
 	enum tus_f_type		type;
 };
 
+/* what ptr points to */
+enum tus_file_core_ptr {
+	TFCP_INVALID = 0,
+	TFCP_CONCAT,
+#define TFCP_READABLE(tfcp) ((tfcp) >= TFCP_ZERO)
+	TFCP_ZERO,
+	TFCP_MMAP_RO,
+	TFCP_MMAP_RW
+};
+
 struct tus_file_core {
 	unsigned			magic;
 #define VMOD_TUS_FILE_CORE_MAGIC	0x105f11e0
@@ -95,6 +105,7 @@ struct tus_file_core {
 	 */
 	int				ref;
 
+	enum tus_file_core_ptr		ptr_type;
 	/* final mmap or concats list */
 	void				*ptr;
 	size_t				len;