tools/testing/selftests/net/skf_net_off.c

File Facts

System

Linux kernel

Corpus path

tools/testing/selftests/net/skf_net_off.c

Extension

.c

Size

5676 bytes

Lines

245

Domain

Support Tooling And Documentation

Bucket

tools

Inferred role

Support Tooling And Documentation: implementation source

Status

source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

• Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
• Touches IRQ or DMA behavior; this matters for the representative real-device path.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• arpa/inet.h
• errno.h
• error.h
• fcntl.h
• getopt.h
• linux/filter.h
• linux/if.h
• linux/if_packet.h
• linux/if_tun.h
• linux/ipv6.h
• netinet/if_ether.h
• netinet/in.h
• netinet/ip.h
• netinet/ip6.h
• netinet/udp.h
• poll.h
• signal.h
• stdbool.h
• stddef.h
• stdio.h
• stdlib.h
• string.h
• sys/ioctl.h
• sys/socket.h
• sys/poll.h
• sys/types.h
• sys/uio.h
• unistd.h

Detected Declarations

• function tun_open
• function sk_set_filter
• function raw_open
• function tun_write
• function raw_read
• function parse_opts
• function main

Annotated Snippet

switch (c) {
		case 'f':
			cfg_do_filter = true;
			printf("bpf filter enabled\n");
			break;
		case 'F':
			cfg_do_frags = true;
			printf("napi frags mode enabled\n");
			break;
		case 'i':
			cfg_ifname = optarg;
			break;
		default:
			error(1, 0, "unknown option %c", optopt);
			break;
		}
	}

	if (!cfg_ifname)
		error(1, 0, "must specify tap interface name (-i)");
}

int main(int argc, char **argv)
{
	int fdt, fdr;

	parse_opts(argc, argv);

	fdr = raw_open();
	fdt = tun_open(cfg_ifname);

	tun_write(fdt);
	raw_read(fdr);

	if (close(fdt))
		error(1, errno, "close tun");
	if (close(fdr))
		error(1, errno, "close udp");

	fprintf(stderr, "OK\n");
	return 0;
}

Annotation

• Immediate include surface: `arpa/inet.h`, `errno.h`, `error.h`, `fcntl.h`, `getopt.h`, `linux/filter.h`, `linux/if.h`, `linux/if_packet.h`.
• Detected declarations: `function tun_open`, `function sk_set_filter`, `function raw_open`, `function tun_write`, `function raw_read`, `function parse_opts`, `function main`.
• Atlas domain: Support Tooling And Documentation / tools.
• Implementation status: source implementation candidate.
• IRQ or DMA behavior appears here, which is relevant to the selected PCIe/NVMe device path.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.