¿Cómo construyo un ejecutable nativo (línea de comando) para ejecutar en Android?

A partir de NDK r8d, esto se puede solucionar de una forma mucho más sencilla.

1. Cree un proyecto con la siguiente jerarquía de directorios:

   project/
       jni/
           Android.mk
           Application.mk
           *.c, *.cpp, *.h, etc.
   

2. Complete Android.mk con el siguiente contenido. Lo más importante es la última línea. Consulte el documento NDK para conocer el significado de las otras variables.

   LOCAL_PATH := $(call my-dir)
   
   include $(CLEAR_VARS)
   
   LOCAL_MODULE := name-of-your-executable
   LOCAL_SRC_FILES := a.cpp b.cpp c.cpp etc.cpp
   LOCAL_CPPFLAGS := -std=gnu++0x -Wall -fPIE         # whatever g++ flags you like
   LOCAL_LDLIBS := -L$(SYSROOT)/usr/lib -llog -fPIE -pie   # whatever ld flags you like
   
   include $(BUILD_EXECUTABLE)    # <-- Use this to build an executable.
   

3. Ir al project/ directorio, y simplemente escriba

   ndk-build
   

   El resultado se colocará en project/libs/<arch>/name-of-your-executable .

http://www.bekatul.info/content/native-c-application-android [roto (9 de noviembre de 2015)]
Enlace de Wayback Machine

Para resumir el artículo...

El código de prueba es:

#include  <stdio.h>//for printf
#include  <stdlib.h>//for exit

int main(int argc, char **argv)
{
        int i = 1;
        i+=2;

        printf("Hello, world (i=%d)!\n", i);

        return 0;
        exit(0);
}

El Makefile es:

APP := test
ROOT := /home/dd/android
INSTALL_DIR := /data/tmp
NDK_PLATFORM_VER := 8

ANDROID_NDK_ROOT := $(ROOT)/android-ndk-r5
ANDROID_NDK_HOST := linux-x86
ANDROID_SDK_ROOT := $(ROOT)/android-sdk-linux_86
PREBUILD := $(ANDROID_NDK_ROOT)/toolchains/arm-eabi-4.4.0/prebuilt/$(ANDROID_NDK_HOST)

BIN := $(PREBUILD)/bin/
LIB := $(ANDROID_NDK_ROOT)/platforms/android-$(NDK_PLATFORM_VER)/arch-arm/usr/lib
INCLUDE := $(ANDROID_NDK_ROOT)/platforms/android-$(NDK_PLATFORM_VER)/arch-arm/usr/include

CC := $(BIN)/arm-eabi-gcc
GDB_CLIENT := $(BIN)/arm-eabi-gdb

LIBCRT := $(LIB)/crtbegin_dynamic.o

LINKER := /system/bin/linker

DEBUG := -g

CFLAGS := $(DEBUG) -fno-short-enums -I$(INCLUDE)
CFLAGS += -Wl,-rpath-link=$(LIB),-dynamic-linker=$(LINKER) -L$(LIB)
CFLAGS += -nostdlib -lc

all: $(APP)

$(APP): $(APP).c
        $(CC) -o [email protected] $< $(CFLAGS) $(LIBCRT)

install: $(APP)
        $(ANDROID_SDK_ROOT)/platform-tools/adb push $(APP) $(INSTALL_DIR)/$(APP) 
        $(ANDROID_SDK_ROOT)/platform-tools/adb shell chmod 777 $(INSTALL_DIR)/$(APP)

shell:
        $(ANDROID_SDK_ROOT)/platform-tools/adb shell

run:
        $(ANDROID_SDK_ROOT)/platform-tools/adb shell $(INSTALL_DIR)/$(APP)

debug-install:
        $(ANDROID_SDK_ROOT)/platform-tools/adb push $(PREBUILD)/../gdbserver $(INSTALL_DIR)/gdbserver
        $(ANDROID_SDK_ROOT)/platform-tools/adb shell chmod 777 $(INSTALL_DIR)/gdbserver

debug-go:
        $(ANDROID_SDK_ROOT)/platform-tools/adb forward tcp:1234: tcp:1234
        $(ANDROID_SDK_ROOT)/platform-tools/adb shell $(INSTALL_DIR)/gdbserver :1234 $(INSTALL_DIR)/$(APP)

debug:
        $(GDB_CLIENT) $(APP)

clean:
        @rm -f $(APP).o $(APP)

El autor almacenó esos archivos en su computadora Linux local en:

/home/dd/android/dev/native/test.c
/home/dd/android/dev/native/Makefile

Luego, el autor lo compiló y lo probó con:

[email protected]:~/android/dev/native$ make clean; make; make install; make run
/home/dd/android/android-ndk-r5/toolchains/arm-eabi-4.4.0/prebuilt/linux-x86/bin//arm-eabi-gcc -c  -fno-short-enums -I/home/dd/android/android-ndk-r5/platforms/android-9/arch-arm/usr/include test.c -o test.o 
/home/dd/android/android-ndk-r5/toolchains/arm-eabi-4.4.0/prebuilt/linux-x86/bin//arm-eabi-g++ -Wl,--entry=main,-dynamic-linker=/system/bin/linker,-rpath-link=/home/dd/android/android-ndk-r5/platforms/android-9/arch-arm/usr/lib -L/home/dd/android/android-ndk-r5/platforms/android-9/arch-arm/usr/lib -nostdlib -lc -o test test.o
/home/dd/android/android-sdk-linux_86/platform-tools/adb push test /data/tmp/test 
45 KB/s (2545 bytes in 0.054s)
/home/dd/android/android-sdk-linux_86/platform-tools/adb shell chmod 777 /data/tmp/test
/home/dd/android/android-sdk-linux_86/platform-tools/adb shell /data/tmp/test
Hello, world (i=3)!

SDK y NDK utilizados fueron:

source code: /home/dd/android/dev/native
android ndk: /home/dd/android/android-ndk-r5
android sdk: /home/dd/android/android-sdk-linux_86

Sin embargo, la guía de depuración fue la parte realmente buena. Copiar y pegar...

Configure la compilación para habilitar la depuración:

DEBUG = -g
CFLAGS := $(DEBUG) -fno-short-enums -I$(ANDROID_NDK_ROOT)/platforms/android-$(NDK_PLATFORM_VER)/arch-arm/usr/include

copie el archivo gdbserver ($(PREBUILD)/../gdbserver) al emulador, agregue el destino en Makefile para que sea más fácil:

debug-install:
        $(ANDROID_SDK_ROOT)/platform-tools/adb push $(PREBUILD)/../gdbserver $(INSTALL_DIR)/gdbserver
        $(ANDROID_SDK_ROOT)/platform-tools/adb shell chmod 777 $(INSTALL_DIR)/gdbserver

Ahora lo depuraremos en el puerto 1234:

debug-go:
        $(ANDROID_SDK_ROOT)/platform-tools/adb forward tcp:1234: tcp:1234
        $(ANDROID_SDK_ROOT)/platform-tools/adb shell $(INSTALL_DIR)/gdbserver :1234 $(INSTALL_DIR)/$(APP)

Luego ejecútalo:

[email protected]:~/android/dev/native$ make clean; make; make install; make debug-install; make debug-go
/home/dd/android/android-ndk-r5/toolchains/arm-eabi-4.4.0/prebuilt/linux-x86/bin//arm-eabi-gcc -c  -g -fno-short-enums -I/home/dd/android/android-ndk-r5/platforms/android-9/arch-arm/usr/include test.c -o test.o 
/home/dd/android/android-ndk-r5/toolchains/arm-eabi-4.4.0/prebuilt/linux-x86/bin//arm-eabi-g++ -Wl,--entry=main,-dynamic-linker=/system/bin/linker,-rpath-link=/home/dd/android/android-ndk-r5/platforms/android-9/arch-arm/usr/lib -L/home/dd/android/android-ndk-r5/platforms/android-9/arch-arm/usr/lib -nostdlib -lc -o test test.o
/home/dd/android/android-sdk-linux_86/platform-tools/adb push test /data/tmp/test 
71 KB/s (3761 bytes in 0.051s)
/home/dd/android/android-sdk-linux_86/platform-tools/adb shell chmod 777 /data/tmp/test
/home/dd/android/android-sdk-linux_86/platform-tools/adb push /home/dd/android/android-ndk-r5/toolchains/arm-eabi-4.4.0/prebuilt/linux-x86/../gdbserver /data/tmp/gdbserver
895 KB/s (118600 bytes in 0.129s)
/home/dd/android/android-sdk-linux_86/platform-tools/adb shell chmod 777 /data/tmp/gdbserver
/home/dd/android/android-sdk-linux_86/platform-tools/adb forward tcp:1234: tcp:1234
/home/dd/android/android-sdk-linux_86/platform-tools/adb shell /data/tmp/gdbserver :1234 /data/tmp/test
Process /data/tmp/test created; pid = 472
Listening on port 1234

Ahora abra otra consola y ejecute el depurador:

[email protected]:~/android/dev/native$ make debug
/home/dd/android/android-ndk-r5/toolchains/arm-eabi-4.4.0/prebuilt/linux-x86/bin//arm-eabi-gdb test
GNU gdb 6.6
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "--host=x86_64-linux-gnu --target=arm-elf-linux"...
(gdb) target remote :1234
Remote debugging using :1234
warning: Unable to find dynamic linker breakpoint function.
GDB will be unable to debug shared library initializers
and track explicitly loaded dynamic code.
0xb0001000 in ?? ()
(gdb) b main
Breakpoint 1 at 0x82fc: file test.c, line 6.
(gdb) c
Continuing.
Error while mapping shared library sections:
/system/bin/linker: No such file or directory.
Error while mapping shared library sections:
libc.so: Success.

Breakpoint 1, main (argc=33512, argv=0x0) at test.c:6
6               int i = 1;
(gdb) n
7               i+=2;
(gdb) p i
$1 = 1
(gdb) n
9               printf("Hello, world (i=%d)!\n", i);
(gdb) p i
$2 = 3
(gdb) c
Continuing.

Program exited normally.
(gdb) quit

Bueno, está bien. Y la otra consola dará una salida adicional así:

Remote debugging from host 127.0.0.1
gdb: Unable to get location for thread creation breakpoint: requested event is not supported
Hello, world (i=3)!

Child exited with retcode = 0 

Child exited with status 0
GDBserver exiting

Aquí hay un proyecto de ejemplo que sigue la respuesta de KennyTM. Puedes crearlo desde cero o modificar otro proyecto, por ejemplo, hello-jni en las muestras del NDK.

jni/main.c:

#include <stdio.h>
int main() {
    printf("hello\n");
    return 0;
}

jni/Aplicación.mk:

#APP_ABI := all
APP_ABI := armeabi-v7a

jni/Android.mk:

LOCAL_PATH := $(call my-dir)

# first target: the hello-jni example
# it shows how to build multiple targets
# {{ you may comment it out
include $(CLEAR_VARS)

LOCAL_MODULE    := hello-jni
LOCAL_SRC_FILES := hello-jni.c
LOCAL_LDLIBS := -llog -L$(LOCAL_PATH)/lib -lmystuff # link to libmystuff.so

include $(BUILD_SHARED_LIBRARY)
#}} you may comment it out


# second target
include $(CLEAR_VARS)

LOCAL_MODULE := hello
LOCAL_SRC_FILES := main.c

include $(BUILD_EXECUTABLE)    # <-- Use this to build an executable.

Debo tener en cuenta que no verá ningún registro en la salida estándar, tendrá que usar adb logcat para verlo.

Entonces, si desea iniciar sesión:

jni/main.c:

#include <stdio.h>
#include <android/log.h>
int main() {
    printf("hello\n");
    __android_log_print(ANDROID_LOG_DEBUG  , "~~~~~~", "log %i", 0); // the 3rd arg is a printf-style format string
    return 0;
}

y la sección correspondiente en jni/Android.mk se convierte en:

LOCAL_PATH := $(call my-dir)

#...

include $(CLEAR_VARS)

LOCAL_MODULE := hello
LOCAL_SRC_FILES := main.c
LOCAL_LDLIBS := -llog   # no need to specify path for liblog.so

include $(BUILD_EXECUTABLE)    # <-- Use this to build an executable.