Crate fakeroot

A simple crate which provides the ability to redirect filesystem calls. This crate builds a library that can be used via LD_PRELOAD.

Some examples follow.

Intercept a file:

mkdir /tmp/etc
echo "tee hee" > /tmp/etc/hosts
FAKEROOT="/tmp" LD_PRELOAD="path/to/libfakeroot.so" cat /etc/hosts
# tee hee

Intercept a directory list:

mkdir /tmp/etc
echo "whatever" > /tmp/etc/🪃
FAKEROOT="/tmp" FAKEROOT_DIRS=1 LD_PRELOAD="path/to/libfakeroot.so" ls /etc
# 🪃

Options are configured via environment variables:

• FAKEROOT: absolute path to the fake root
• FAKEROOT_DIRS: whether or not to intercept directory listing calls too
• FAKEROOT_ALL: whether or not to fake non-existent files and directories
• FAKEROOT_DEBUG: if set, will debug log to STDERR

Structs

• fopen
• open
• open64
• opendir

Constants

• ENV_FAKEROOT
  Required: absolute path to the directory to use as the fake root
• ENV_FAKEROOT_ALL
  Optional: should non existent files be faked?
• ENV_FAKEROOT_DEBUG
  Optional: should this hook log debug information to STDERR?
• ENV_FAKEROOT_DIRS
  Optional: should this also hook directories?

Functions

• my_fopen^⚠
• my_open^⚠
• my_open64^⚠
• my_opendir^⚠