[wasm2c] Add rot13 example (#1384)

This example demonstrates how to use imported functions. The `rot13`
program takes each command line argument, and rot13-encodes it.

The exported `rot13` function has no arguments, and instead calls back
into the program (via `fill_buf`) with a buffer to fill in. When the
function finishes it calls `buf_done`.

(rot13.wat is the same as in src/test-interp.cc.)

1 files changed, 10 insertions, 0 deletions

diff --git a/wasm2c/.gitignore b/wasm2c/.gitignore
new file mode 100644
index 00000000..47ea610d
--- /dev/null
+++ b/wasm2c/.gitignore
@@ -0,0 +1,10 @@
+wasm-rt-impl.o
+examples/fac/main.o
+examples/fac/fac
+examples/fac/fac.o
+examples/rot13/main.o
+examples/rot13/rot13
+examples/rot13/rot13.c
+examples/rot13/rot13.h
+examples/rot13/rot13.o
+examples/rot13/rot13.wasm