1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <errno.h>
4 #include <iconv.h>
5 
6 static iconv_t s_cd;
7 
8 /* Call iconv_open only once so the benchmark will be faster? */
init_iconv(void)9 static void __attribute__ ((constructor)) init_iconv(void)
10 {
11 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
12     s_cd = iconv_open("UTF-16LE", "UTF-8");
13 #else
14     s_cd = iconv_open("UTF-16BE", "UTF-8");
15 #endif
16     if (s_cd == (iconv_t)-1) {
17         perror("iconv_open");
18         exit(1);
19     }
20 }
21 
22 /*
23  * Parameters:
24  * - buf8, len8: input utf-8 string
25  * - buf16: buffer to store decoded utf-16 string
26  * - *len16: on entry - utf-16 buffer length in bytes
27  *           on exit  - length in bytes of valid decoded utf-16 string
28  * Returns:
29  *  -  0: success
30  *  - >0: error position of input utf-8 string
31  *  - -1: utf-16 buffer overflow
32  * LE/BE depends on host
33  */
utf8_to16_iconv(const unsigned char * buf8,size_t len8,unsigned short * buf16,size_t * len16)34 int utf8_to16_iconv(const unsigned char *buf8, size_t len8,
35         unsigned short *buf16, size_t *len16)
36 {
37     size_t ret, len16_save = *len16;
38     const unsigned char *buf8_0 = buf8;
39 
40     ret = iconv(s_cd, (char **)&buf8, &len8, (char **)&buf16, len16);
41 
42     *len16 = len16_save - *len16;
43 
44     if (ret != (size_t)-1)
45         return 0;
46 
47     if (errno == E2BIG)
48         return -1;              /* Output buffer full */
49 
50     return buf8 - buf8_0 + 1;   /* EILSEQ, EINVAL, error position */
51 }
52