php内置函数分析之ucfirst()、lcfirst()

 1 /* {{{ php_ucfirst
 2    Uppercase the first character of the word in a native string */
 3 static void php_ucfirst(char *str)
 4 {
 5     register char *r;
 6     r = str;
 7     *r = toupper((unsigned char) *r);
 8 }
 9 /* }}} */
10 
11 /* {{{ proto string ucfirst(string str)
12    Makes a string‘s first character uppercase */
13 PHP_FUNCTION(ucfirst)
14 {
15     zend_string *str;
16 
17     ZEND_PARSE_PARAMETERS_START(1, 1)
18         Z_PARAM_STR(str)
19     ZEND_PARSE_PARAMETERS_END();
20 
21     if (!ZSTR_LEN(str)) {
22         RETURN_EMPTY_STRING();
23     }
24 
25     ZVAL_STRINGL(return_value, ZSTR_VAL(str), ZSTR_LEN(str));
26     php_ucfirst(Z_STRVAL_P(return_value));
27 }
28 /* }}} */