在Linux中保持共享库调用的数据(Persisting Data Across Shared Library Calls in Linux)

 背景 
 
 我正在开发一个管理嵌入式以太网交换机的共享库。 该库由各种交换机感知管理应用程序调用，旨在成为该设备的唯一接口。 有问题的特定交换机是为企业应用程序设计的，并期望控制CPU管理大部分内部状态。 为此，我需要存储一个数据表，该数据表将在不同应用程序的多个库调用中持续存在。 
 
 为此，我一直在考虑使用适当的并发保护共享内存。 然而，由于共享库的动态特性，这引发了许多问题。 
 
 问题 
 
 （1）是否总是需要一个正在运行的进程来保留这个内存？ 
 
 （2）由于我的库经常被加载和卸载，所有调用退出后会发生什么？ 那个人“拥有”记忆还是泄漏？ 
 
 （3）是否有更好的系统可以在我的库的多个调用中持久保存一组struct （我曾考虑过平面文件，但文件系统访问非常有限）。 
 
 附加信息 
 
 
 
 对库的单独调用是原子的和独立的。 
 
 
 该库没有依赖关系，也不会fork任何子代。 
 
 
 需要在单元的整个启动时间内维护被跟踪的数据。 
 
 
 该平台是3.x Linux内核的自定义版本。 
 
 
 所有代码都是用C语言编写的，重点是可重用性和可移植性。 
 

Background
 
I am developing a shared library that manages an embedded Ethernet switch. This library is called by an assortment of switch-aware management applications and is designed to be the only interface to the device. The particular switch in question is designed for enterprise applications and expects the controlling CPU to manage much of the internal state. To do this, I need to store a table of data that will persist across multiple calls of the library from different applications.
 
To this end, I have been considering shared memory with the appropriate concurrency guards. This, however raises a number of questions due to the dynamic nature of a shared library.
 
Questions
 
(1) Does there always need to be a running process to retain this memory?
 
(2) Since my library is constantly being loaded and unloaded, what happens when all calls exit? Who "owns" the memory at that point or does it leak?
 
(3) Is there a better system to persist an array of structs across multiple calls of my library (I had considered flat files but filesystem access is quite limited).
 
Additional Information
 
 
 
Individual calls to the library are atomic and independent.
 
 
The library has no dependencies and does not fork any children.
 
 
The data being tracked needs to be maintained for the entire boot time of the unit.
 
 
The platform is a custom version of the 3.x Linux kernel.
 
 
All code is being written in C with a focus on reusability and portability.
 

原文：https://stackoverflow.com/questions/31485229