test: prove package initialization semantics

test/sep/limitexec.c

@@ -0,0 +1,36 @@
+#define _POSIX_C_SOURCE 200809L
+#include <errno.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/resource.h>
+#include <unistd.h>
+
+/* Test-only deterministic launcher for allocation-failure observers.  Keeping
+ * setrlimit in a repository-built helper avoids depending on util-linux paths
+ * or shell-specific ulimit syntax. */
+int
+main(int argc, char **argv)
+{
+	if (argc < 3) {
+		fputs("usage: sep-limitexec bytes program [arg ...]\n", stderr);
+		return 2;
+	}
+	errno = 0;
+	char *end = NULL;
+	unsigned long long value = strtoull(argv[1], &end, 10);
+	if (errno != 0 || end == argv[1] || *end != '\0') {
+		fputs("sep-limitexec: invalid limit\n", stderr);
+		return 2;
+	}
+	struct rlimit limit;
+	limit.rlim_cur = (rlim_t)value;
+	limit.rlim_max = (rlim_t)value;
+	if (setrlimit(RLIMIT_AS, &limit) != 0) {
+		fputs("sep-limitexec: setrlimit failed\n", stderr);
+		return 2;
+	}
+	execv(argv[2], &argv[2]);
+	fputs("sep-limitexec: exec failed\n", stderr);
+	return 127;
+}