A Makefile for building adb outside of a full AOSP tools build, motivated by a need to get a security-enabled ADB onto the Raspberry Pi

Makefile

#ADB tool for the Raspberry Pi and similar environments not supported by the Android SDK.
#based on https://gist.github.com/splhack/958335

#This is a very simple hack for building adb on its own, using a lot of stock Linux libraries (libssl, libcrypt) 
#in place of the versions shipped with AOSP, in order to avoid having to pull down a lot of code.

#git clone https://android.googlesource.com/platform/system/core system/core

#The method below does not work with the most recent version (you will see const char* conversion errors
#as a C file has been changed to a CPP one where that is more strict).  However, it _can_ be made to work
#with an adb version new enough to support security, if we revert the tree

#The following state of the tree was not chosen with care; it just happened to be what was on the machine
#where I first tried this, and it worked.  Other versions may or may not work

#cd system/core/adb
#git reset caed3d9fae1fd372dfa01cb60fbf157233c9052e

#copy this Makefile into that directory, ie, system/core/adb/Makefile

#make 

SRCS+= adb.c
SRCS+= console.c
SRCS+= transport.c
SRCS+= transport_local.c
SRCS+= transport_usb.c
SRCS+= commandline.c
SRCS+= adb_client.c
SRCS+= adb_auth_host.c 
SRCS+= sockets.c
SRCS+= services.c
SRCS+= file_sync_client.c
SRCS+= fdevent.c
SRCS+= get_my_path_linux.c
SRCS+= usb_linux.c
#SRCS+= usb_vendors.c
#SRCS+= utils.c

VPATH+= ../libcutils
#SRCS+= abort_socket.c
SRCS+= socket_inaddr_any_server.c
SRCS+= socket_local_client.c
SRCS+= socket_local_server.c
SRCS+= socket_loopback_client.c
SRCS+= socket_loopback_server.c
SRCS+= socket_network_client.c

VPATH+= ../libzipfile
SRCS+= centraldir.c
SRCS+= zipfile.c

#VPATH+= ../../../external/zlib
#SRCS+= adler32.c
#SRCS+= compress.c
#SRCS+= crc32.c
#SRCS+= deflate.c
#SRCS+= infback.c
#SRCS+= inffast.c
#SRCS+= inflate.c
#SRCS+= inftrees.c
#SRCS+= trees.c
#SRCS+= uncompr.c
#SRCS+= zutil.c

VPATH+=../libcutils
SRCS+=load_file.c

CPPFLAGS+= -DADB_HOST=1
CPPFLAGS+= -DHAVE_FORKEXEC=1
CPPFLAGS+= -DHAVE_SYMLINKS
CPPFLAGS+= -DHAVE_TERMIO_H
CPPFLAGS+= -D_GNU_SOURCE
CPPFLAGS+= -D_XOPEN_SOURCE
CPPFLAGS+= -I.
CPPFLAGS+= -I../include
#CPPFLAGS+= -I../../../external/zlib

CFLAGS+= -O2 -g -Wall -Wno-unused-parameter
LDFLAGS= #-static
LIBS= -lrt -lpthread -lcrypto -lssl -lz

TOOLCHAIN=
CC= $(TOOLCHAIN)gcc
LD= $(TOOLCHAIN)gcc

OBJS= $(SRCS:.c=.o)

all: adb

adb: $(OBJS)
	$(LD) -o $@ $(LDFLAGS) $(OBJS) $(LIBS)

clean:
	rm -rf $(OBJS)

im trying to compile this in my raspberry pi and gettng allot of errors:
g++ -DADB_HOST=1 -DHAVE_FORKEXEC=1 -DHAVE_SYMLINKS -DHAVE_TERMIO_H -D_GNU_SOURCE -D_XOPEN_SOURCE -I. -I../include -c -o adb.o adb.cpp
In file included from adb.cpp:30:0:
sysdeps.h: In function ‘char* adb_dirstart(const char_)’:
sysdeps.h:517:28: error: invalid conversion from ‘const char_’ to ‘char_’ [-fpermissive]
sysdeps.h: In function ‘char_ adb_dirstop(const char_)’:
sysdeps.h:522:29: error: invalid conversion from ‘const char_’ to ‘char_’ [-fpermissive]
adb.cpp: In function ‘apacket_ get_apacket()’:
adb.cpp:146:14: error: ‘nullptr’ was not declared in this scope
adb.cpp: In function ‘int handle_forward_request(const char_, transport_type, char_, int)’:
adb.cpp:720:23: error: ‘nullptr’ was not declared in this scope
adb.cpp:753:40: error: invalid conversion from ‘const char_’ to ‘char_’ [-fpermissive]
: recipe for target 'adb.o' failed
make: *** [adb.o] Error 1

how i can fix this?