Test OaSis

OaSis has focused host tests and manual QEMU integration checks. There is no single automated test runner for the complete kernel because port I/O, paging, disk access, and VGA require an emulator.

Run the host network test

test_network.c links the IPv4 implementation with small test doubles for Ethernet, ARP, ICMP, VGA output, and itoa. It checks checksum vectors, odd-length input, valid protocol dispatch, invalid checksums, and truncated IPv4 lengths.

Run it from the repository root:

gcc -std=c99 -Wall -Wextra -Iinclude \
  -ffreestanding -fno-builtin \
  -c test_network.c -o /tmp/test_network.o
gcc -std=c99 -Wall -Wextra -Iinclude \
  -ffreestanding -fno-builtin \
  -c src/kernel/drivers/ip.c -o /tmp/test_ip.o
gcc /tmp/test_network.o /tmp/test_ip.o \
  -o /tmp/test_network
/tmp/test_network

Expected output:

ok: RFC 1071 checksum
ok: odd-length checksum
ok: valid IPv4 dispatch
ok: bad checksum rejected
ok: truncated total length rejected

These checks do not emulate PCI configuration space, RTL8139 DMA, or QEMU networking.

Run the existing libc tests

The test_libc/ directory contains a separate freestanding libc test Makefile:

make -C test_libc

Its test program exercises the small printf and standard-library implementation. It is independent of the kernel image.

Run the manual QEMU smoke test

Build the image and boot with the development configuration:

make clean
make
make run

In the OaSis shell, run each command in order:

pci
nicinfo
arp
ping 10.0.2.2
arp
dmesg

A successful networking test should show:

1. PCI output containing a Realtek 10EC:8139 device or a network-class fallback.
2. A nonzero RTL8139 I/O base and a six-byte MAC from nicinfo.
3. An ARP cache entry for 10.0.2.2 after the first ping.
4. ICMP reply lines for the four ping probes.
5. No reset, DMA, TX timeout, or exception messages in dmesg.

Troubleshoot failures

• No ethernet controller found: verify -nic user,model=rtl8139 in make run.
• rtl8139: not thistialized: inspect PCI BAR0 and reset output.
• DMA buffer is not mapped: inspect paging and the low-memory kernel layout.
• arp: request transmit failed: inspect the RTL8139 TX status and descriptor output.
• ARP resolve failed: check whether QEMU is using the expected guest network and whether an ARP entry appeared.
• No ICMP replies after ARP succeeds: inspect IPv4 and ICMP dispatch logs.

The shell uses VGA text mode. Use a normal QEMU window for manual testing rather than -nographic.