patch 7.4.1779

brammool · brammool · commit 73dfe917ba63 · 2016-04-23T13:54:48.000+02:00
Problem:    Using negative index in strcharpart(). (Yegappan Lakshmanan)
Solution:   Assume single byte when using a negative iindex.
diff --git a/src/eval.c b/src/eval.c
@@ -19774,7 +19774,12 @@ f_strcharpart(typval_T *argvars, typval_T *rettv)
 	    charlen = get_tv_number(&argvars[2]);
 	    while (charlen > 0 && nbyte + len < slen)
 	    {
-		len += mb_char2len(p[nbyte + len]);
+		int off = nbyte + len;
+
+		if (off < 0)
+		    len += 1;
+		else
+		    len += mb_char2len(p[off]);
 		--charlen;
 	    }
 	}
diff --git a/src/version.c b/src/version.c
@@ -753,6 +753,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1779,
 /**/
     1778,
 /**/

Original file line number	Diff line number	Diff line change
`@@ -19774,7 +19774,12 @@ f_strcharpart(typval_T argvars, typval_T rettv)`
`19774`	`19774`	`charlen = get_tv_number(&argvars[2]);`
`19775`	`19775`	`while (charlen > 0 && nbyte + len < slen)`
`19776`	`19776`	`{`
`19777`		`- len += mb_char2len(p[nbyte + len]);`
	`19777`	`+ int off = nbyte + len;`
	`19778`	`+`
	`19779`	`+ if (off < 0)`
	`19780`	`+ len += 1;`
	`19781`	`+ else`
	`19782`	`+ len += mb_char2len(p[off]);`
`19778`	`19783`	`--charlen;`
`19779`	`19784`	`}`
`19780`	`19785`	`}`