x86, relocs: Refactor the relocs tool to merge 32- and 64-bit ELF

Refactor the relocs tool so that the same tool can handle 32- and
64-bit ELF.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/1365797627-20874-5-git-send-email-keescook@chromium.org

arch/x86/tools/relocs_common.c

@@ -0,0 +1,76 @@
+#include "relocs.h"
+
+void die(char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	exit(1);
+}
+
+static void usage(void)
+{
+	die("relocs [--abs-syms|--abs-relocs|--text|--realmode] vmlinux\n");
+}
+
+int main(int argc, char **argv)
+{
+	int show_absolute_syms, show_absolute_relocs;
+	int as_text, use_real_mode;
+	const char *fname;
+	FILE *fp;
+	int i;
+	unsigned char e_ident[EI_NIDENT];
+
+	show_absolute_syms = 0;
+	show_absolute_relocs = 0;
+	as_text = 0;
+	use_real_mode = 0;
+	fname = NULL;
+	for (i = 1; i < argc; i++) {
+		char *arg = argv[i];
+		if (*arg == '-') {
+			if (strcmp(arg, "--abs-syms") == 0) {
+				show_absolute_syms = 1;
+				continue;
+			}
+			if (strcmp(arg, "--abs-relocs") == 0) {
+				show_absolute_relocs = 1;
+				continue;
+			}
+			if (strcmp(arg, "--text") == 0) {
+				as_text = 1;
+				continue;
+			}
+			if (strcmp(arg, "--realmode") == 0) {
+				use_real_mode = 1;
+				continue;
+			}
+		}
+		else if (!fname) {
+			fname = arg;
+			continue;
+		}
+		usage();
+	}
+	if (!fname) {
+		usage();
+	}
+	fp = fopen(fname, "r");
+	if (!fp) {
+		die("Cannot open %s: %s\n", fname, strerror(errno));
+	}
+	if (fread(&e_ident, 1, EI_NIDENT, fp) != EI_NIDENT) {
+		die("Cannot read %s: %s", fname, strerror(errno));
+	}
+	rewind(fp);
+	if (e_ident[EI_CLASS] == ELFCLASS64)
+		process_64(fp, use_real_mode, as_text,
+			   show_absolute_syms, show_absolute_relocs);
+	else
+		process_32(fp, use_real_mode, as_text,
+			   show_absolute_syms, show_absolute_relocs);
+	fclose(fp);
+	return 0;
+}