Add moxiebox as a choice for libc

This required some rework of the libc selection, as moxiebox is a layer on
top of another libc - newlib.

Also, moxiebox'es host VM (`sandbox`) needs a libcrypto on the host. We will
not have it if we're cross-compiling a canadian cross. Fortunately, all moxiebox
needs from libcrypto is SHA256, and it already includes a standalone implementation
of SHA256 in its runtime. Provide a little wrapper that allows moxiebox use
that implementation for the host binary, too.

Also, automate collecting/printing the list of all packages in a given category
(e.g. LIBC or COMP_TOOLS), generate a list of all Kconfig symbols for a given
category.

Signed-off-by: Alexey Neyman <stilor@att.net>

4 files changed, 79 insertions, 0 deletions

diff --git a/packages/moxiebox/git-9a79ac54/0001-Remove-PKG_CONFIG-check.patch b/packages/moxiebox/git-9a79ac54/0001-Remove-PKG_CONFIG-check.patch
new file mode 100644
index 00000000..ca3456f2
--- /dev/null
+++ b/packages/moxiebox/git-9a79ac54/0001-Remove-PKG_CONFIG-check.patch
@@ -0,0 +1,29 @@
+From a59675779247f544695959646a1615a033ca2d8d Mon Sep 17 00:00:00 2001
+From: Alexey Neyman <stilor@att.net>
+Date: Tue, 20 Nov 2018 10:54:40 -0800
+Subject: [PATCH] Remove PKG_CONFIG check
+
+... it is not used afterwards anyway, and causes errors if pkg-config
+is not installed (since one cannot just run configure - one has to
+run autogen.sh first).
+
+Signed-off-by: Alexey Neyman <stilor@att.net>
+---
+ configure.ac | 1 -
+ 1 file changed, 1 deletion(-)
+
+diff --git a/configure.ac b/configure.ac
+index aeadb36..1925a88 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -22,7 +22,6 @@ AC_PATH_TOOL(STRIP, strip)
+ AC_CHECK_PROG(MOX_AS, moxiebox-as, moxiebox-as)
+ AC_CHECK_PROG(MOX_AR, moxiebox-ar, moxiebox-ar)
+ AC_CHECK_PROG(MOX_GCC, moxiebox-gcc, moxiebox-gcc)
+-PKG_PROG_PKG_CONFIG
+ 
+ AC_LANG_PUSH([C++])
+ 
+-- 
+2.14.1
+
diff --git a/packages/moxiebox/package.desc b/packages/moxiebox/package.desc
new file mode 100644
index 00000000..67937586
--- /dev/null
+++ b/packages/moxiebox/package.desc
@@ -0,0 +1,2 @@
+repository='git https://github.com/jgarzik/moxiebox.git'
+repository_cset='9a79ac546faa4196b66e279f8017814ba8d6fd4b'
diff --git a/packages/moxiebox/sha.h b/packages/moxiebox/sha.h
new file mode 100644
index 00000000..36b90a18
--- /dev/null
+++ b/packages/moxiebox/sha.h
@@ -0,0 +1,23 @@
+/*
+    Wrapper around moxiebox'es implementation of SHA256 digest that
+    mimics the API of the OpenSSL implementation.
+*/
+
+#ifndef __SHA_H_
+#define __SHA_H_
+
+#ifdef  __cplusplus
+extern "C" {
+#endif
+
+#include "../runtime/sandboxrt_crypto.h"
+#define SHA256_DIGEST_LENGTH SHA256_BLOCK_SIZE
+void SHA256_Init(SHA256_CTX *ctx);
+void SHA256_Update(SHA256_CTX *ctx, const void *data, size_t len);
+void SHA256_Final(unsigned char *md, SHA256_CTX *ctx);
+
+#ifdef  __cplusplus
+}
+#endif
+
+#endif
diff --git a/packages/moxiebox/sha256_wrap.c b/packages/moxiebox/sha256_wrap.c
new file mode 100644
index 00000000..15800c42
--- /dev/null
+++ b/packages/moxiebox/sha256_wrap.c
@@ -0,0 +1,25 @@
+/*
+    Wrapper around moxiebox'es implementation of SHA256 digest that
+    mimics the API of the OpenSSL implementation.
+*/
+
+#include "sha.h"
+#include "../runtime/sha256.c"
+
+void
+SHA256_Init(SHA256_CTX *ctx)
+{
+    sha256_init(ctx);
+}
+
+void
+SHA256_Update(SHA256_CTX *ctx, const void *data, size_t len)
+{
+    sha256_update(ctx, data, len);
+}
+
+void
+SHA256_Final(unsigned char *md, SHA256_CTX *ctx)
+{
+    sha256_final(ctx, md);
+}