使用rabbitmq-c作为静态库会出现错误:致命错误:amqp.h:没有这样的文件或目录

Question

我正试图将rabbitmq-c构建为一个静态库，以便在AWS lambda中使用。

我能够根据文档构建示例，这些示例运行良好。

但现在我正在尝试在我自己的项目中使用。以下是我采取的步骤：

1. 已克隆https://github.com/alanxz/rabbitmq-c在第三方目录中
2. 在我的源目录中，我正在使用cmake进行构建

下面是我的CMakeLists.txt

cmake_minimum_required(VERSION 3.1)
set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_CXX_EXTENSIONS OFF)
set(CMAKE_BUILD_TYPE "Release")
project(executable LANGUAGES CXX)
SET(CMAKE_FIND_LIBRARY_SUFFIXES ".a")
SET(BUILD_SHARED_LIBS OFF)
set(RABBITMQ_TARGET "<absolute_path_to_third_party_dir>/third_party/rabbitmq-c/")
add_definitions(-DAMQP_STATIC)
add_subdirectory(${RABBITMQ_TARGET})
include_directories(${LIBRABBITMQ_INCLUDE_DIRS})
add_executable(${PROJECT_NAME} execute_code.cpp)
target_link_libraries(executable PRIVATE ${RMQ_LIBRARY_TARGET})

3. 我运行cmake .. -DBUILD_EXAMPLES=OFF -DBUILD_SHARED_LIBS=OFF(它工作时没有任何问题(
4. 但当我执行make时，会出现以下错误：

fatal error: amqp.h: No such file or directory
compilation terminated.
CMakeFiles/executable.dir/build.make:62: recipe for target 'CMakeFiles/executable.dir/execute_code.cpp.o' failed
make[2]: *** [CMakeFiles/executable.dir/execute_code.cpp.o] Error 1
CMakeFiles/Makefile2:169: recipe for target 'CMakeFiles/executable.dir/all' failed
make[1]: *** [CMakeFiles/executable.dir/all] Error 2
Makefile:129: recipe for target 'all' failed
make: *** [all] Error 2

这是我的execute_code.cpp(我只是为了这里删除不必要的代码(

#include<iostream>
#include <amqp.h>
#include <amqp_tcp_socket.h>
using namespace std;
int main(int argc, char** argv) {
char const *hostname;
int port, status;
char const *exchange;
char const *bindingkey;
amqp_socket_t *socket = NULL;
amqp_connection_state_t conn;
amqp_bytes_t queuename;
conn = amqp_new_connection();
socket = amqp_tcp_socket_new(conn);
return 0;
}

当我不使用时

#include <amqp.h>
#include <amqp_tcp_socket.h>

我能够构建rabbitmq-static，下面是生成响应

Scanning dependencies of target rabbitmq-static
[ 35%] Building C object third_party/rabbitmq-c/librabbitmq/CMakeFiles/rabbitmq-static.dir/amqp_framing.c.o
[ 37%] Building C object third_party/rabbitmq-c/librabbitmq/CMakeFiles/rabbitmq-static.dir/amqp_api.c.o
[ 40%] Building C object third_party/rabbitmq-c/librabbitmq/CMakeFiles/rabbitmq-static.dir/amqp_connection.c.o
[ 42%] Building C object third_party/rabbitmq-c/librabbitmq/CMakeFiles/rabbitmq-static.dir/amqp_mem.c.o
[ 44%] Building C object third_party/rabbitmq-c/librabbitmq/CMakeFiles/rabbitmq-static.dir/amqp_socket.c.o
[ 46%] Building C object third_party/rabbitmq-c/librabbitmq/CMakeFiles/rabbitmq-static.dir/amqp_table.c.o
[ 48%] Building C object third_party/rabbitmq-c/librabbitmq/CMakeFiles/rabbitmq-static.dir/amqp_url.c.o
[ 51%] Building C object third_party/rabbitmq-c/librabbitmq/CMakeFiles/rabbitmq-static.dir/amqp_tcp_socket.c.o
[ 53%] Building C object third_party/rabbitmq-c/librabbitmq/CMakeFiles/rabbitmq-static.dir/amqp_time.c.o
[ 55%] Building C object third_party/rabbitmq-c/librabbitmq/CMakeFiles/rabbitmq-static.dir/amqp_consumer.c.o
[ 57%] Building C object third_party/rabbitmq-c/librabbitmq/CMakeFiles/rabbitmq-static.dir/amqp_openssl.c.o
[ 60%] Building C object third_party/rabbitmq-c/librabbitmq/CMakeFiles/rabbitmq-static.dir/amqp_openssl_hostname_validation.c.o
[ 62%] Building C object third_party/rabbitmq-c/librabbitmq/CMakeFiles/rabbitmq-static.dir/amqp_hostcheck.c.o
[ 64%] Building C object third_party/rabbitmq-c/librabbitmq/CMakeFiles/rabbitmq-static.dir/amqp_openssl_bio.c.o
[ 66%] Linking C static library librabbitmq.a
[ 66%] Built target rabbitmq-static

它能够生成librabbitmq.a，因此能够静态构建。

我试过了https://github.com/alanxz/rabbitmq-c/releases/tag/v0.10.0这是最新的稳定版本。但仍然是同样的错误。

我试着搜索这个问题，但找不到任何有用的东西。

我几乎是cmake的新手，你能告诉我我做错了什么吗？或者我错过了什么？

Answer 1

rabbitmq-c存储库在rabbitmq-c/librabbitmq子目录中设置LIBRABBITMQ_INCLUDE_DIRS变量，然后使用PARENT_SCOPE进行设置，使其在顶级rabbitmq-c目录中也可用。请参阅此处的代码：

set(LIBRABBITMQ_INCLUDE_DIRS
${CMAKE_CURRENT_BINARY_DIR}
${CMAKE_CURRENT_SOURCE_DIR}
${SOCKET_IMPL}
${MSINTTYPES_INCLUDE}
)
include_directories(${LIBRABBITMQ_INCLUDE_DIRS})
set(LIBRABBITMQ_INCLUDE_DIRS
${LIBRABBITMQ_INCLUDE_DIRS}
PARENT_SCOPE)

但是，当您通过add_subdirectory将rabbitmq-crepo包含在项目中时，它会引入一个附加作用域，并且LIBRABBITMQ_INCLUDE_DIRS变量在此父-父作用域中不可用。您将不得不：

1. 重新组织您的CMake项目，使您的项目位于rabbitmq-c存储库中(尽管这是不可扩展的，可能不是您想要做的(
2. 修改顶层rabbitmq-cCMake文件以进一步扩展此变量的范围
3. 在机器上安装rabbitmq-c，并使用CMake查找模块或CMake配置文件(例如rabbitmq-c-config.cmake(由CCD_ 14提供以定位安装的软件

Answer 2

聚会有点晚，我今天偶然发现了同样的问题。

Kevin提出的3个解决方案都不适合我的需求(lib被声明为子模块，所以我不能修改它，也不会安装在生产机器上(

对我来说，解决方案是将rabbitmq-include目录添加到链接lib:的目标

target_include_directories("${PROJECT_NAME}" PUBLIC include/ path/to/rabbitmq-c/librabbitmq)