I had planned all sorts of things (and my hospital was very "eat what you like as long as your doctor sys it's okay") but then found that I threw up anything I managed to get down.
So I guess I'd suggest things that taste and look more or less the same going down as they do coming up.
I had packed little toast squares, honey packets to put on the toast for extra energy or to eat alone, and a thermos of Tom Kah Gai (a thai coconut-chicken soup, very light but also very yummy!). I brought a few different types of tea bags, and a few cans of juice.
I also had preggie pops, three or four Luna bars (peppermint flavor, my fav) and frozen fruit bars. My hospital had a kitchen for laboring couples that they kept stocked with juice and little finger foods and a freezer/fridge to keep whatever you'd like during your "stay with them" (like those frozen fruit bars). You might want to find out if your hospital has something similar...I know my dh more or less lived off the freebie foods for a day or two!