Add network_interface option to bind outgoing HTTP requests to a spec…

[mmarwah]

Summary

• Adds char * network_interface field to struct _u_request in ulfius.h, allowing callers to bind outgoing HTTP requests to a specific network interface or IP address (via libcurl's CURLOPT_INTERFACE)
• Initializes the field to NULL in ulfius_init_request, frees and nulls it in ulfius_clean_request, and deep-copies it in ulfius_copy_request
• In ulfius_send_http_request, sets CURLOPT_INTERFACE on the curl handle when network_interface is non-NULL, with appropriate error logging on failure

[mnjdhl]

Null check is not required before free?

[mmarwah]

Null check is done in o_free().

https://github.com/babelouest/orcania/blob/master/src/memory.c#L35

[babelouest]

Hello,

Although I understand the need, I'm not sure it's a good idea to add libcurl options that are not "mainstream". My future self would have difficulties to maintain too much options that are not used so much...