/*
 * 600_6l — linker smoke. Drive w6c → w6a → w6l on a tiny program,
 * confirm the result is a static ELF executable with no PT_INTERP.
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

int
main(void)
{
	const char *bin = getenv("BIN");
	if (!bin) bin = "out/bin";

	char src[64], asmf[64], obj[64], exe[64];
	snprintf(src, sizeof src, "/tmp/wwt_%d.ww", getpid());
	snprintf(asmf, sizeof asmf, "/tmp/wwt_%d.s", getpid());
	snprintf(obj, sizeof obj, "/tmp/wwt_%d.o", getpid());
	snprintf(exe, sizeof exe, "/tmp/wwt_%d.x", getpid());

	FILE *f = fopen(src, "wb");
	fputs("fn main() i32 = { return 42; };", f);
	fclose(f);

	char cmd[1024];
	snprintf(cmd, sizeof cmd, "%s/w6c -o %s %s", bin, asmf, src);
	if (system(cmd) != 0) { fprintf(stderr, "w6c failed\n"); return 1; }
	snprintf(cmd, sizeof cmd, "%s/w6a -o %s %s", bin, obj, asmf);
	if (system(cmd) != 0) { fprintf(stderr, "w6a failed\n"); return 1; }
	snprintf(cmd, sizeof cmd, "%s/w6l -o %s %s", bin, exe, obj);
	if (system(cmd) != 0) { fprintf(stderr, "w6l failed\n"); return 1; }

	/* validate ELF magic + e_type=EXEC */
	FILE *of = fopen(exe, "rb");
	if (of == NULL) { fprintf(stderr, "exe missing\n"); return 1; }
	unsigned char hdr[20];
	if (fread(hdr, 1, sizeof hdr, of) != sizeof hdr) { fprintf(stderr, "short exe\n"); fclose(of); return 1; }
	fclose(of);

	if (memcmp(hdr, "\x7f""ELF", 4) != 0 || hdr[4] != 2) {
		fprintf(stderr, "not an ELF64\n"); return 1;
	}
	/* e_type at offset 16, little-endian u16; ET_EXEC = 2 */
	unsigned short etype = (unsigned short)hdr[16] | ((unsigned short)hdr[17] << 8);
	if (etype != 2) {
		fprintf(stderr, "not ET_EXEC, got %u\n", etype); return 1;
	}

	/* ldd "not a dynamic executable" — proxy: check that file is not
	 * dynamic by looking for PT_INTERP. We have none, so ldd reports
	 * "not a dynamic executable" or similar. */
	snprintf(cmd, sizeof cmd, "ldd %s 2>&1", exe);
	FILE *p = popen(cmd, "r");
	char buf[256] = {0};
	fread(buf, 1, sizeof buf - 1, p);
	pclose(p);
	if (strstr(buf, "not a dynamic executable") == NULL
	    && strstr(buf, "statically linked") == NULL) {
		fprintf(stderr, "ldd says not static: %s\n", buf);
		return 1;
	}

	unlink(src); unlink(asmf); unlink(obj); unlink(exe);
	printf("w6l: ok\n");
	return 0;
}