MFC r307808: elfcopy: select mode by the end of the program name

The mode of operation (elfcopy, mcs, or strip) is chosen based on the
program name.  Broaden this to allow a substring match at the end of the
name to allow prefixes - for example, bsdstrip or aarch64-freebsd-strip.

This improves use of these tools as drop-in replacements for GNU objcopy
and strip, which are often built with a limited set of supported targets
and installed with a target prefix for cross tools.

1 files changed, 23 insertions, 3 deletions

diff --git a/contrib/elftoolchain/elfcopy/main.c b/contrib/elftoolchain/elfcopy/main.c
index e8e1875..b85845a 100644
--- a/contrib/elftoolchain/elfcopy/main.c
+++ b/contrib/elftoolchain/elfcopy/main.c
@@ -1536,6 +1536,22 @@ print_version(void)
 	exit(EXIT_SUCCESS);
 }
 
+/*
+ * Compare the ending of s with end.
+ */
+static int
+strrcmp(const char *s, const char *end)
+{
+	size_t endlen, slen;
+
+	slen = strlen(s);
+	endlen = strlen(end);
+
+	if (slen >= endlen)
+		s += slen - endlen;
+	return (strcmp(s, end));
+}
+
 int
 main(int argc, char **argv)
 {
@@ -1569,12 +1585,16 @@ main(int argc, char **argv)
 	if ((ecp->progname = ELFTC_GETPROGNAME()) == NULL)
 		ecp->progname = "elfcopy";
 
-	if (strcmp(ecp->progname, "strip") == 0)
+	if (strrcmp(ecp->progname, "strip") == 0)
 		strip_main(ecp, argc, argv);
-	else if (strcmp(ecp->progname, "mcs") == 0)
+	else if (strrcmp(ecp->progname, "mcs") == 0)
 		mcs_main(ecp, argc, argv);
-	else
+	else {
+		if (strrcmp(ecp->progname, "elfcopy") != 0 &&
+		    strrcmp(ecp->progname, "objcopy") != 0)
+			warnx("program mode not known, defaulting to elfcopy");
 		elfcopy_main(ecp, argc, argv);
+	}
 
 	free_sec_add(ecp);
 	free_sec_act(ecp);