Merge "Remove interrupter." into main

package {

    // See: http://go/android-license-faq

    // A large-scale-change added 'default_applicable_licenses' to import

    // all of the 'license_kinds' from "frameworks_base_license"

    // to get the below license kinds:

    //   SPDX-license-identifier-Apache-2.0

    default_applicable_licenses: ["frameworks_base_license"],

}

cc_library_shared {

    name: "interrupter",

    host_supported: true,

    srcs: ["interrupter.c"],

    cflags: [

        "-Wall",

        "-Werror",

        "-Wunused",

        "-Wunreachable-code",

    ],

}

/*

 * Copyright 2012, The Android Open Source Project

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#define _GNU_SOURCE

/**

 * The probability of a syscall failing from 0.0 to 1.0

 */

#define PROBABILITY 0.9

#include <stdio.h>

#include <stdlib.h>

#include <errno.h>

/* for various intercepted calls */

#include <sys/types.h>

#include <sys/socket.h>

#include <sys/stat.h>

#include <fcntl.h>

#include <dlfcn.h>

#include "interrupter.h"

static int probability = PROBABILITY * RAND_MAX;

static int maybe_interrupt() {

    if (rand() < probability) {

        return 1;

    }

    return 0;

}

DEFINE_INTERCEPT(read, ssize_t, int, void*, size_t);

DEFINE_INTERCEPT(write, ssize_t, int, const void*, size_t);

DEFINE_INTERCEPT(accept, int, int, struct sockaddr*, socklen_t*);

DEFINE_INTERCEPT(creat, int, const char*, mode_t);

/*

 * Copyright 2012, The Android Open Source Project

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#define CONCATENATE(arg1, arg2)   CONCATENATE1(arg1, arg2)

#define CONCATENATE1(arg1, arg2)  CONCATENATE2(arg1, arg2)

#define CONCATENATE2(arg1, arg2)  arg1##arg2

#define INTERRUPTER(sym) \

    if (real_##sym == NULL) \

        __init_##sym(); \

    if (maybe_interrupt()) { \

        errno = EINTR; \

        return -1; \

    }

#define CALL_FUNCTION_1(sym, ret, type1) \

ret (*real_##sym)(type1) = NULL; \

ret sym(type1 arg1) { \

    INTERRUPTER(sym) \

    return real_##sym(arg1); \

}

#define CALL_FUNCTION_2(sym, ret, type1, type2) \

ret (*real_##sym)(type1, type2) = NULL; \

ret sym(type1 arg1, type2 arg2) { \

    INTERRUPTER(sym) \

    return real_##sym(arg1, arg2); \

}

#define CALL_FUNCTION_3(sym, ret, type1, type2, type3) \

ret (*real_##sym)(type1, type2, type3) = NULL; \

ret sym(type1 arg1, type2 arg2, type3 arg3) { \

    INTERRUPTER(sym) \

    return real_##sym(arg1, arg2, arg3); \

}

#define CALL_FUNCTION_4(sym, ret, type1, type2, type3, type4) \

ret (*real_##sym)(type1, type2, type3, type4) = NULL; \

ret sym(type1 arg1, type2 arg2, type3 arg3, type4 arg4) { \

    INTERRUPTER(sym) \

    return real_##sym(arg1, arg2, arg3, arg4); \

}

#define CALL_FUNCTION_5(sym, ret, type1, type2, type3, type4, type5) \

ret (*real_##sym)(type1, type2, type3, type4, type5) = NULL; \

ret sym(type1 arg1, type2 arg2, type3 arg3, type4 arg4, type5 arg5) { \

    INTERRUPTER(sym) \

    return real_##sym(arg1, arg2, arg3, arg4, arg5); \

}

#define DEFINE_INTERCEPT_N(N, sym, ret, ...) \

static void __init_##sym(void); \

CONCATENATE(CALL_FUNCTION_, N)(sym, ret, __VA_ARGS__) \

static void __init_##sym(void) { \

    real_##sym = dlsym(RTLD_NEXT, #sym); \

    if (real_##sym == NULL) { \

        fprintf(stderr, "Error hooking " #sym ": %s\n", dlerror()); \

    } \

}

#define INTERCEPT_NARG(...) INTERCEPT_NARG_N(__VA_ARGS__, INTERCEPT_RSEQ_N())

#define INTERCEPT_NARG_N(...) INTERCEPT_ARG_N(__VA_ARGS__)

#define INTERCEPT_ARG_N(_1, _2, _3, _4, _5, _6, _7, _8, N, ...) N

#define INTERCEPT_RSEQ_N() 8, 7, 6, 5, 4, 3, 2, 1, 0

#define DEFINE_INTERCEPT(sym, ret, ...) DEFINE_INTERCEPT_N(INTERCEPT_NARG(__VA_ARGS__), sym, ret, __VA_ARGS__)