MF51: fix #34757 (iconv_substr() gives "Unknown error" when offset > string length)

diff --git a/ext/iconv/iconv.c b/ext/iconv/iconv.c
index 45aff4a7eb3e299dec5097be9dc6f880eb5329e4..afa6b3b8165a99cd333a4aa629f215cbe3aff319 100644 (file)
--- a/ext/iconv/iconv.c
+++ b/ext/iconv/iconv.c
@@ -586,26 +586,38 @@ static php_iconv_err_t _php_iconv_substr(smart_str *pretval,
        size_t out_left;
 
        unsigned int cnt;
-
+       unsigned int total_len;
+       
+       err = _php_iconv_strlen(&total_len, str, nbytes, enc);
+       if (err != PHP_ICONV_ERR_SUCCESS) {
+               return err;
+       }
+       
        /* normalize the offset and the length */
-       if (offset < 0 || len < 0) {
-               unsigned int total_len;
-               err = _php_iconv_strlen(&total_len, str, nbytes, enc);
-               if (err != PHP_ICONV_ERR_SUCCESS) {
-                       return err;
-               }
-               if (offset < 0) {
-                       if ((offset += total_len) < 0) {
-                               offset = 0;
-                       }
+       if (offset < 0) {
+               if ((offset += total_len) < 0) {
+                       offset = 0;
                }
-               if (len < 0) {
-                       if ((len += (total_len - offset)) < 0) {
-                               len = 0;
-                       }
+       }
+       if (len < 0) {
+               if ((len += (total_len - offset)) < 0) {
+                       len = 0;
                }
        }
 
+       if (offset >= total_len) {
+               return PHP_ICONV_ERR_SUCCESS;
+       }
+       
+       if ((offset + len) > total_len) {
+               /* trying to compute the length */
+               len = total_len - offset;
+       }
+
+       if (len == 0) {
+               return PHP_ICONV_ERR_SUCCESS;
+       }
+       
        cd1 = iconv_open(GENERIC_SUPERSET_NAME, enc);
 
        if (cd1 == (iconv_t)(-1)) {