standalone linux app nearly ready

also made several fixes that apply to the OSX app

standalone/linux/README

@@ -0,0 +1,23 @@
+To start the git-annex webapp, run the git-annex-webapp script in this
+directory.
+
+To enter an environment with git-annex in PATH, use runshell
+
+This should work on any Linux system of the appropriate architecture.
+More or less. There are no external dependencies, except for glibc.
+Any recent-ish version of glibc should work (2.13 is ok; so is 2.11).
+
+
+How it works: This directory contains a lot of libraries and programs
+that git-annex needs. But it's not a chroot. Instead, runshell sets
+PATH and LD_LIBRARY_PATH to point to the stuff in this directory.
+
+The glibc libs are not included. Instead, it runs with the host system's
+glibc. We trust that glibc's excellent backwards and forward compatability
+is good enough to run binaries that were linked for a newer or older
+version. Of course, this could fail. Particularly if the binaries try to
+use some new glibc feature. But hopefully not.
+
+Why not bundle glibc too? I've not gotten it to work! The host system's 
+ld-linux.so will be used for sure, as that's hardcoded into the binaries.
+When I tried including libraries from glibc in here, everything segfaulted.

standalone/linux/git-annex-webapp

@@ -0,0 +1,25 @@
+#!/bin/sh
+base="$(dirname $0)"
+if [ ! -d "$base" ]; then
+	echo "** cannot find base directory (I seem to be $0)" >&2
+	exit 1
+fi
+if [ ! -e "$base/runshell" ]; then
+	echo "** cannot find $base/runshell" >&2
+	exit 1
+fi
+
+# Get absolute path to base, to avoid breakage when things change directories.
+orig="$(pwd)"
+cd "$base"
+base="$(pwd)"
+cd "$orig"
+
+# If this is a standalone app, set a variable that git-annex can use to
+# install itself.
+if [ -e "$base/bin/git-annex" ]; then
+	GIT_ANNEX_APP_BASE="$base"
+	export GIT_ANNEX_APP_BASE
+fi
+
+"$base/runshell" git-annex webapp "$@"

standalone/linux/glibc-libs

@@ -0,0 +1,43 @@
+libanl-.*.so
+libutil-.*.so
+libnss_hesiod-.*.so
+libcrypt-.*.so
+libnss_compat-.*.so
+libm-.*.so
+libr.so
+libpcprofile.so
+libnss_nis-.*.so
+libSegFault.so
+libpthread-.*.so
+librt-.*.so
+libnss_dns-.*.so
+libdl-.*.so
+libBrokenLocale-.*.so
+libnss_nisplus-.*.so
+libthread_db-1.0.so
+libmemusage.so
+libcidn-.*.so
+libnss_files-.*.so
+libnsl-.*.so
+libc-.*.so
+ld-.*.so
+libnss_nis.so
+libthread_db.so
+libanl.so
+libr.so
+libnss_compat.so
+libm.so
+libnss_dns.so
+libpthread.so
+libc.so
+librt.so
+libcidn.so
+libnss_nisplus.so
+libnsl.so
+libutil.so
+libBrokenLocale.so
+ld-linux.so
+libnss_files.so
+libdl.so
+libnss_hesiod.so
+libcrypt.so

standalone/linux/runshell

@@ -0,0 +1,48 @@
+#!/bin/sh
+# Runs a shell command (or interactive shell) using the binaries and
+# libraries bundled with this app.
+
+set -e
+
+base="$(dirname $0)"
+
+if [ ! -d "$base" ]; then
+	echo "** cannot find base directory (I seem to be $0)" >&2
+	exit 1
+fi
+
+if [ ! -e "$base/bin/git-annex" ]; then
+	echo "** base directory $base does not contain bin/git-annex" >&2
+	exit 1
+fi
+if [ ! -e "$base/bin/git" ]; then
+	echo "** base directory $base does not contain bin/git" >&2
+	exit 1
+fi
+
+# Get absolute path to base, to avoid breakage when things change directories.
+orig="$(pwd)"
+cd "$base"
+base="$(pwd)"
+cd "$orig"
+
+# Put our binaries first, to avoid issues with out of date or incompatable
+# system binaries.
+PATH=$base/bin:$PATH
+export PATH
+
+for lib in $(cat $base/libdirs); do
+	LD_LIBRARY_PATH="$base/$lib:$LD_LIBRARY_PATH"
+done
+export LD_LIBRARY_PATH
+
+GIT_EXEC_PATH=$base/git-core
+export GIT_EXEC_PATH
+
+if [ "$1" ]; then
+	cmd="$1"
+	shift 1
+	exec "$cmd" "$@"
+else
+	$SHELL
+fi