Где я могу найти читателя Lisp в C?

Гэри Нотт Интерпретация Лиспа очень хороша. You may also try others, like Jim Mayfield's Lisp. There are probably lots of little Lisps out there...

You mentioned that you don't like C. Maybe you'd like Haskell -- in which case you could try "Write yourself a Scheme in 48 hours", an interesting tutorial (you get to write a Scheme interpreter in Haskell).

Update: I know that a Lisper would hardly feel comfortable using Haskell, but hey, it's much more comfortable than C (at least for me)! Besides that, HAskell has a good FFI, so it should be easy to use the Haskell-made Lisp-reader as a C-compatible library.

Update 2: If you want to use XLisp, as suggested by another user, you will probably need src/xlread.c (863 lines) and include/xlisp.h (1379 lines) -- but I could be wrong...

Update 3: If you use Gary Knott's Lisp (one single C file with 942 lines), the function signature is int32 sread(void). This would be my choie if I didn't need anything fancy (like read macros) or highly optimized (there is a PDF paper that describes how the code is implemented, so you won't have to find your way in a labyrinth). The documentation for the function is:

This procedure scans an input string g using a lexical token scanning
routine, e(), where e() returns
                    1 if the token is '('
                    2 if the token is '''
                    3 if the token is '.'
                    4 if the token is ')'   or a typed pointer d to an
atom or number stored in row ptrv(d) in   the atom or number tables.
Due to the typecode (8 or 9) of d, d is a negative 32-bit integer.  The
token found by e() is stripped from the front of g.

SREAD constructs an S-expression and returns a typed pointer to it as
its result.

See that Gary's Lisp is old and you'll need to change it so it compiles. Instead of including linuxenv.h, include:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <setjmp.h>

Also, it does not work in 64-bit machines (the documentation of sread should tell you why...)

Update 4: There's also the Scheme implementations by Nils Holm (there are books describing the internals)

there are lots of embeddable Scheme implementations, off the top of my head: SIOD, Guile, ChickenScheme, Scheme48....

lispreader - это простой синтаксический анализатор файлов Lisp, выполненный на простом языке C.

Если вам нужен C ++, вы можете покопаться в исходном коде SuperTux , он содержит синтаксический анализатор файлов Lisp, написанный на C ++.

Если вам нужна реальная реализация Lisp, а не просто синтаксический анализатор, вы можете взглянуть на Abuse , который содержит небольшую версию языка сценариев игр.