blockdev: Replace drive_add()'s fmt, ... by optstr parameter

Let the callers build the optstr.  Only one wants to.  All the others
become simpler, because they don't have to worry about escaping '%'.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

blockdev.c

@@ -93,17 +93,11 @@ QemuOpts *drive_def(const char *optstr)
 }
 
 QemuOpts *drive_add(BlockInterfaceType type, int index, const char *file,
-                    const char *fmt, ...)
+                    const char *optstr)
 {
-    va_list ap;
-    char optstr[1024];
     QemuOpts *opts;
     char buf[32];
 
-    va_start(ap, fmt);
-    vsnprintf(optstr, sizeof(optstr), fmt, ap);
-    va_end(ap);
-
     opts = drive_def(optstr);
     if (!opts) {
         return NULL;

blockdev.h

@@ -47,10 +47,7 @@ DriveInfo *drive_get_by_blockdev(BlockDriverState *bs);
 
 QemuOpts *drive_def(const char *optstr);
 QemuOpts *drive_add(BlockInterfaceType type, int index, const char *file,
-                    const char *fmt, ...) /*GCC_FMT_ATTR(4, 5)*/;
-    /* GCC_FMT_ATTR() commented out to avoid the (pretty useless)
-     * "zero-length gnu_printf format string" warning we insist to
-     * enable */
+                    const char *optstr);
 DriveInfo *drive_init(QemuOpts *arg, int default_to_scsi, int *fatal_error);
 
 /* device-hotplug */

vl.c

@@ -621,7 +621,6 @@ static int bt_parse(const char *opt)
 /***********************************************************/
 /* QEMU Block devices */
 
-/* Any % in the following strings must be escaped as %% */
 #define HD_OPTS "media=disk"
 #define CDROM_OPTS "media=cdrom"
 #define FD_OPTS ""
@@ -2050,17 +2049,21 @@ int main(int argc, char **argv, char **envp)
                 initrd_filename = optarg;
                 break;
             case QEMU_OPTION_hda:
+                {
+                    char buf[256];
                     if (cyls == 0)
-                    hda_opts = drive_add(IF_DEFAULT, 0, optarg, HD_OPTS);
+                        snprintf(buf, sizeof(buf), "%s", HD_OPTS);
                     else
-                    hda_opts = drive_add(IF_DEFAULT, 0, optarg, HD_OPTS
-			     ",cyls=%d,heads=%d,secs=%d%s",
-                             cyls, heads, secs,
+                        snprintf(buf, sizeof(buf),
+                                 "%s,cyls=%d,heads=%d,secs=%d%s",
+                                 HD_OPTS , cyls, heads, secs,
                                  translation == BIOS_ATA_TRANSLATION_LBA ?
                                  ",trans=lba" :
                                  translation == BIOS_ATA_TRANSLATION_NONE ?
                                  ",trans=none" : "");
+                    drive_add(IF_DEFAULT, 0, optarg, buf);
                     break;
+                }
             case QEMU_OPTION_hdb:
             case QEMU_OPTION_hdc:
             case QEMU_OPTION_hdd: