tools/objtool/signal.c

Source file repositories/reference/linux-study-clean/tools/objtool/signal.c

File Facts

System
Linux kernel
Corpus path
tools/objtool/signal.c
Extension
.c
Size
2865 bytes
Lines
136
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.

Dependency Surface

Detected Declarations

Annotated Snippet

if (strstr(line, "[stack]")) {
			if (sscanf(line, "%lx-%lx", &stack_start, &stack_end) != 2) {
				ERROR_GLIBC("sscanf");
				ret = -1;
				goto done;
			}
			stack_limit = stack_end - rlim.rlim_cur;
			goto done;
		}
	}

	ret = -1;
	ERROR("/proc/self/maps: can't find [stack]");

done:
	fclose(fp);

	return ret;
}

int init_signal_handler(void)
{
	int signals[] = {SIGSEGV, SIGBUS, SIGILL, SIGABRT};
	struct sigaction sa;
	stack_t ss;

	if (read_stack_limit())
		return -1;

	ss.ss_sp = malloc(SIGSTKSZ);
	if (!ss.ss_sp) {
		ERROR_GLIBC("malloc");
		return -1;
	}
	ss.ss_size = SIGSTKSZ;
	ss.ss_flags = 0;

	if (sigaltstack(&ss, NULL) == -1) {
		ERROR_GLIBC("sigaltstack");
		return -1;
	}

	sa.sa_sigaction = signal_handler;
	sigemptyset(&sa.sa_mask);

	sa.sa_flags = SA_ONSTACK | SA_SIGINFO;

	for (int i = 0; i < ARRAY_SIZE(signals); i++) {
		if (sigaction(signals[i], &sa, NULL) == -1) {
			ERROR_GLIBC("sigaction");
			return -1;
		}
	}

	return 0;
}

Annotation

Implementation Notes