mbsalign: cleanup escape sequences handling

Use '\033' (portable) instead of '\e' (GNU extension), simplify
the control character handling by checking for ESC directly, and
fix the SCS boundary check to only match complete sequences.

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/lib/mbsalign.c b/lib/mbsalign.c
index 3e79ad10b4e8e8476a607cb44b1317bd541c539a..3a1385fec027e6f1e8cd9b30712b390365b94415 100644 (file)
--- a/lib/mbsalign.c
+++ b/lib/mbsalign.c
@@ -42,14 +42,9 @@ size_t mbs_nwidth(const char *buf, size_t bufsz)
                last = p + (bufsz - 1);
 
        while (p && *p && p <= last) {
-               if (iscntrl((unsigned char) *p)) {
-                       char ctrl_char = *p;
+               if (*p == '\033') {
                        p++;
 
-                       /* only process escape sequences if the control char is ESC */
-                       if (ctrl_char != '\e')
-                               continue;
-
                        /* try detect "\e[x;ym" and skip on success */
                        if (*p && *p == '[') {
                                const char *e = p;
@@ -59,11 +54,12 @@ size_t mbs_nwidth(const char *buf, size_t bufsz)
                                        p = e + 1;
                        }
                        /* try detect SCS sequences "\e(X", "\e)X", "\e*X", "\e+X" and skip on success */
-                       else if (*p && (*p == '(' || *p == ')' || *p == '*' || *p == '+')) {
-                               p++;  /* skip the SCS introducer */
-                               if (p <= last)
-                                       p++;  /* skip the character */
-                       }
+                       else if (p < last && (*p == '(' || *p == ')' || *p == '*' || *p == '+'))
+                               p += 2;  /* skip the SCS sequence */
+                       continue;
+               }
+               if (iscntrl((unsigned char) *p)) {
+                       p++;
                        continue;
                }
 #ifdef HAVE_WIDECHAR