add: iovec_to_iovec routine (#241)

[VasilyStepanov]

This pull request enhances the rawstorstd library by adding a crucial utility function for iovec operations, enabling more flexible and efficient data manipulation between scattered memory buffers. Concurrently, the testing suite has been modernized to better support and verify these new capabilities, ensuring robustness and maintainability.

Highlights

• New iovec utility function: Introduced rawstor_iovec_to_iovec, a new function designed to efficiently copy data from a source iovec array to a destination iovec array, respecting a given offset.
• Improved Test Infrastructure: The IOVecTest class was refactored to utilize std::list<std::string> for managing source data, simplifying memory management by removing manual malloc and free calls.
• Comprehensive Test Coverage: Added a new test case, TEST_F(IOVecTest, to_iovec), to thoroughly validate the functionality of the newly implemented rawstor_iovec_to_iovec function under different offset and data transfer scenarios.

(cherry picked from commit 9d66b05)

[gemini-code-assist]

Summary of Changes

Hello @VasilyStepanov, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces a new core utility function, rawstor_iovec_to_iovec, to the rawstorstd library, enabling more flexible and efficient data transfer between scattered memory buffers. Concurrently, the testing suite has been modernized to improve memory management and ensure robust validation of this new capability, enhancing the library's overall reliability and maintainability.

Highlights

• New iovec utility function: Introduced rawstor_iovec_to_iovec, a new function designed to efficiently copy data from a source iovec array to a destination iovec array, respecting a given offset.
• Improved Test Infrastructure: The IOVecTest class was refactored to utilize std::list<std::string> for managing source data, simplifying memory management by removing manual malloc and free calls.
• Comprehensive Test Coverage: Added a new test case, TEST_F(IOVecTest, to_iovec), to thoroughly validate the functionality of the newly implemented rawstor_iovec_to_iovec function under different offset and data transfer scenarios.

Changelog

• librawstorstd/include/rawstorstd/iovec.h
  • Added the declaration for the new rawstor_iovec_to_iovec function.
• librawstorstd/src/iovec.c
  • Implemented the rawstor_iovec_to_iovec function, which copies data from a source iovec array to a destination iovec array, starting from a specified offset in the source.
• librawstorstd/tests/test_iovec.cpp
  • Included <list> and <string> headers for new test infrastructure.
  • Refactored the IOVecTest class to use std::list<std::string> for managing source data, eliminating manual memory allocation and deallocation.
  • Added a new test case, TEST_F(IOVecTest, to_iovec), to thoroughly validate the functionality of the rawstor_iovec_to_iovec function.

Activity

• No human activity has been recorded on this pull request yet.

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[gemini-code-assist]

Code Review

This pull request introduces a new utility function rawstor_iovec_to_iovec for copying data between iovec arrays and modernizes the test suite by using std::list<std::string> for data management, which is a great improvement. The new function is well-structured, but I've found a couple of issues: a critical portability issue due to pointer arithmetic on void*, and a high-severity bug where copying stops prematurely on zero-length buffers. I've also suggested improving the test coverage to catch such bugs in the future. Overall, a valuable addition with a few corrections needed.