*: no-warn pragmas for non-const format strings

We do use non-constant/literal format strings in a few places for more
or less valid reasons;  put `ignored "-Wformat-nonliteral"` around those
so we can have the warning enabled for everywhere else.

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>

bgpd/bgp_dump.c

@@ -117,9 +117,13 @@ static FILE *bgp_dump_open_file(struct bgp_dump *bgp_dump)
 	if (bgp_dump->filename[0] != DIRECTORY_SEP) {
 		snprintf(fullpath, sizeof(fullpath), "%s/%s", vty_get_cwd(),
 			 bgp_dump->filename);
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+		/* user supplied date/time format string */
 		ret = strftime(realpath, MAXPATHLEN, fullpath, &tm);
 	} else
 		ret = strftime(realpath, MAXPATHLEN, bgp_dump->filename, &tm);
+#pragma GCC diagnostic pop
 
 	if (ret == 0) {
 		flog_warn(EC_BGP_DUMP, "%s: strftime error", __func__);

ldpd/log.c

@@ -77,7 +77,11 @@ log_warn(const char *emsg, ...)
 			vlog(LOG_ERR, emsg, ap);
 			logit(LOG_ERR, "%s", strerror(errno));
 		} else {
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+			/* format extended above */
 			vlog(LOG_ERR, nfmt, ap);
+#pragma GCC diagnostic pop
 			free(nfmt);
 		}
 		va_end(ap);

lib/printf/glue.c

@@ -293,5 +293,9 @@ static ssize_t printfrr_va(struct fbuf *buf, struct printfrr_eargs *ea,
 	 * when allocating a larger buffer in asnprintfrr()
 	 */
 	va_copy(ap, *vaf->va);
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+	/* can't format check this */
 	return vbprintfrr(buf, vaf->fmt, ap);
+#pragma GCC diagnostic pop
 }

lib/printf/vfprintf.c

@@ -504,14 +504,20 @@ reswitch:	switch (ch) {
 				fmt[4] = ch;
 				fmt[5] = '\0';
 
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
 				snprintf(buf, sizeof(buf), fmt, prec, arg);
+#pragma GCC diagnostic pop
 			} else {
 				double arg = GETARG(double);
 				char fmt[5] = "%.*";
 				fmt[3] = ch;
 				fmt[4] = '\0';
 
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
 				snprintf(buf, sizeof(buf), fmt, prec, arg);
+#pragma GCC diagnostic pop
 			}
 			cp = buf;
 			/* for proper padding */

lib/vty.c

@@ -343,6 +343,15 @@ void vty_hello(struct vty *vty)
 		vty_out(vty, "%s", host.motd);
 }
 
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+/* prompt formatting has a %s in the cmd_node prompt string.
+ *
+ * Also for some reason GCC emits the warning on the end of the function
+ * (optimization maybe?) rather than on the vty_out line, so this pragma
+ * wraps the entire function rather than just the vty_out line.
+ */
+
 /* Put out prompt and wait input from user. */
 static void vty_prompt(struct vty *vty)
 {
@@ -350,6 +359,7 @@ static void vty_prompt(struct vty *vty)
 		vty_out(vty, cmd_prompt(vty->node), cmd_hostname_get());
 	}
 }
+#pragma GCC diagnostic pop
 
 /* Send WILL TELOPT_ECHO to remote server. */
 static void vty_will_echo(struct vty *vty)
@@ -464,8 +474,12 @@ static int vty_command(struct vty *vty, char *buf)
 			 vty->address);
 
 		/* format the prompt */
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+		/* prompt formatting has a %s in the cmd_node prompt string */
 		snprintf(prompt_str, sizeof(prompt_str), cmd_prompt(vty->node),
 			 vty_str);
+#pragma GCC diagnostic pop
 
 		/* now log the command */
 		zlog_notice("%s%s", prompt_str, buf);

lib/yang_translator.c

@@ -339,8 +339,12 @@ yang_translate_xpath(const struct yang_translator *translator, int dir,
 	if (!mapping)
 		return YANG_TRANSLATE_NOTFOUND;
 
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+	/* processing format strings from mapping node... */
 	n = sscanf(xpath, mapping->xpath_from_fmt, keys[0], keys[1], keys[2],
 		   keys[3]);
+#pragma GCC diagnostic pop
 	if (n < 0) {
 		flog_warn(EC_LIB_YANG_TRANSLATION_ERROR,
 			  "%s: sscanf() failed: %s", __func__,
@@ -348,8 +352,12 @@ yang_translate_xpath(const struct yang_translator *translator, int dir,
 		return YANG_TRANSLATE_FAILURE;
 	}
 
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+	/* processing format strings from mapping node... */
 	snprintf(xpath, xpath_len, mapping->xpath_to_fmt, keys[0], keys[1],
 		 keys[2], keys[3]);
+#pragma GCC diagnostic pop
 
 	return YANG_TRANSLATE_SUCCESS;
 }

lib/zlog.c

@@ -743,7 +743,11 @@ const char *zlog_msg_text(struct zlog_msg *msg, size_t *textlen)
 		fb.outpos_i = 0;
 
 		va_copy(args, msg->args);
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+		/* format-string checking is done further up the chain */
 		need += vbprintfrr(&fb, msg->fmt, args);
+#pragma GCC diagnostic pop
 		va_end(args);
 
 		msg->textlen = need;
@@ -762,7 +766,11 @@ const char *zlog_msg_text(struct zlog_msg *msg, size_t *textlen)
 			fb.outpos_i = 0;
 
 			va_copy(args, msg->args);
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+			/* same as above */
 			vbprintfrr(&fb, msg->fmt, args);
+#pragma GCC diagnostic pop
 			va_end(args);
 
 			bputch(&fb, '\n');

vtysh/vtysh.c

@@ -2759,6 +2759,15 @@ static char *do_prepend(struct vty *vty, struct cmd_token **argv, int argc)
 	return frrstr_join(argstr, argc + off, " ");
 }
 
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+/* 'headline' is a format string with a %s for the daemon name
+ *
+ * Also for some reason GCC emits the warning on the end of the function
+ * (optimization maybe?) rather than on the vty_out line, so this pragma
+ * wraps the entire function rather than just the vty_out line.
+ */
+
 static int show_per_daemon(struct vty *vty, struct cmd_token **argv, int argc,
 			   const char *headline)
 {
@@ -2777,6 +2786,7 @@ static int show_per_daemon(struct vty *vty, struct cmd_token **argv, int argc,
 
 	return ret;
 }
+#pragma GCC diagnostic pop
 
 static int show_one_daemon(struct vty *vty, struct cmd_token **argv, int argc,
 			   const char *name)
@@ -4353,7 +4363,11 @@ char *vtysh_prompt(void)
 {
 	static char buf[512];
 
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+	/* prompt formatting has a %s in the cmd_node prompt string. */
 	snprintf(buf, sizeof(buf), cmd_prompt(vty->node), cmd_hostname_get());
+#pragma GCC diagnostic pop
 	return buf;
 }
 

watchfrr/watchfrr.c

@@ -512,7 +512,11 @@ static int run_job(struct restart_info *restart, const char *cmdtype,
 	restart->kills = 0;
 	{
 		char cmd[strlen(command) + strlen(restart->name) + 1];
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+		/* user supplied command string has a %s for the daemon name */
 		snprintf(cmd, sizeof(cmd), command, restart->name);
+#pragma GCC diagnostic pop
 		if ((restart->pid = run_background(cmd)) > 0) {
 			thread_add_timer(master, restart_kill, restart,
 					 gs.restart_timeout, &restart->t_kill);