untested http custom file handler

src/http.c

 #include "log.h"
 #include "http.h"
 
+
 void http_init(void) {
     httpd_init();
 }
+
+#ifdef DEBUG_DISK_WRITE_SOURCES
+
+#include "lwip/apps/fs.h"
+#include <string.h>
+#include "pack_data.h"
+
+int fs_open_custom(struct fs_file *file, const char *name) {
+    if (strcmp(name, "/src.tar.xz") == 0) {
+        memset(file, 0, sizeof(struct fs_file));
+        file->data = (const char *)data_tar_xz;
+        file->len = data_tar_xz_len;
+        file->index = file->len;
+        file->flags = FS_FILE_FLAGS_HEADER_PERSISTENT;
+        return 1;
+    }
+    return 0;
+}
+
+void fs_close_custom(struct fs_file *file) {
+    (void)file;
+}
+
+#endif // DEBUG_DISK_WRITE_SOURCES