fix broken %s and %[ with no width specifier in wide scanf

[musl] / src / stdio / vfwscanf.c

diff --git a/src/stdio/vfwscanf.c b/src/stdio/vfwscanf.c
index 92b7fa4..a52ba3a 100644 (file)
--- a/src/stdio/vfwscanf.c
+++ b/src/stdio/vfwscanf.c
@@ -214,13 +214,14 @@ int vfwscanf(FILE *f, const wchar_t *fmt, va_list ap)
                        break;
 
                case 's':
+                       if (width < 1) width = -1;
                        s = dest;
                        while (width && !iswspace(c=getwc(f)) && c!=EOF) {
                                int l = wctomb(s?s:tmp, c);
                                if (l<0) goto input_fail;
                                if (s) s+=l;
                                pos++;
-                               width--;
+                               width-=(width>0);
                        }
                        if (width) ungetwc(c, f);
                        if (s) *s = 0;
@@ -228,8 +229,9 @@ int vfwscanf(FILE *f, const wchar_t *fmt, va_list ap)
 
                case 'S':
                        wcs = dest;
+                       if (width < 1) width = -1;
                        while (width && !iswspace(c=getwc(f)) && c!=EOF)
-                               width--, pos++, *wcs++ = c;
+                               width-=(width>0), pos++, *wcs++ = c;
                        if (width) ungetwc(c, f);
                        if (wcs) *wcs = 0;
                        break;
@@ -243,7 +245,9 @@ int vfwscanf(FILE *f, const wchar_t *fmt, va_list ap)
 
                        int gotmatch = 0;
 
-                       for (;;) {
+                       if (width < 1) width = -1;
+
+                       while (width) {
                                if ((c=getwc(f))<0) break;
                                if (in_set(p, c) == invert)
                                        break;
@@ -255,9 +259,10 @@ int vfwscanf(FILE *f, const wchar_t *fmt, va_list ap)
                                        if (s) s+=l;
                                }
                                pos++;
+                               width-=(width>0);
                                gotmatch=1;
                        }
-                       ungetwc(c, f);
+                       if (width) ungetwc(c, f);
 
                        if (!gotmatch) goto match_fail;