diff --git a/src/launcher/apps-common.c b/src/launcher/apps-common.c
index 3508eac..8fdee19 100644
--- a/src/launcher/apps-common.c
+++ b/src/launcher/apps-common.c
@@ -81,31 +81,25 @@ void expand_exec(DesktopEntry *entry, const char *path)
                 p++;
                 if (!*p)
                     break;
+                size_t remaining = buf_size - (size_t)(q - exec2);
                 if (*p == 'i' && entry->icon != NULL) {
-                    snprintf(q, buf_size, "--icon '%s'", entry->icon);
-                    char *old = q;
+                    snprintf(q, remaining, "--icon '%s'", entry->icon);
                     q += strlen("--icon ''");
                     q += strlen(entry->icon);
-                    buf_size -= (size_t)(q - old);
                     q--; // To balance the q++ in the for
                 } else if (*p == 'c' && entry->name != NULL) {
-                    snprintf(q, buf_size, "'%s'", entry->name);
-                    char *old = q;
+                    snprintf(q, remaining, "'%s'", entry->name);
                     q += strlen("''");
                     q += strlen(entry->name);
-                    buf_size -= (size_t)(q - old);
                     q--; // To balance the q++ in the for
                 } else if (*p == 'c') {
-                    snprintf(q, buf_size, "'%s'", path);
-                    char *old = q;
+                    snprintf(q, remaining, "'%s'", path);
                     q += strlen("''");
                     q += strlen(path);
-                    buf_size -= (size_t)(q - old);
                     q--; // To balance the q++ in the for
                 } else if (*p == 'f' || *p == 'F') {
-                    snprintf(q, buf_size, "%c%c", '%', *p);
+                    snprintf(q, remaining, "%c%c", '%', *p);
                     q += 2;
-                    buf_size -= 2;
                     q--; // To balance the q++ in the for
                 } else {
                     // We don't care about other expansions