linux下宽字节转多字节

#include <iconv.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int convert_encoding(const char *from_charset, const char *to_charset,
                    const char *input, size_t input_len, char *output, size_t output_len) {
    iconv_t cd = iconv_open(to_charset, from_charset);
    if (cd == (iconv_t)-1) {
        perror("iconv_open");
        return -1;
    }

    char *inbuf = (char *)input;
    char *outbuf = output;
    size_t inbytesleft = input_len;
    size_t outbytesleft = output_len;

    if (iconv(cd, &inbuf, &inbytesleft, &outbuf, &outbytesleft) == (size_t)-1) {
        perror("iconv");
        iconv_close(cd);
        return -1;
    }

    iconv_close(cd);
    return 0;
}

int main() {
    const char *wide_str = L"Hello, 世界"; // 宽字符串
    size_t wide_len = wcslen(wide_str) * sizeof(wchar_t);

    char mb_str[100]; // 多字节字符串缓冲区
    memset(mb_str, 0, sizeof(mb_str));

    if (convert_encoding("WCHAR_T", "UTF-8", (const char *)wide_str, wide_len, mb_str, sizeof(mb_str)) == 0) {
        printf("Converted string: %s
", mb_str);
    } else {
        printf("Conversion failed
");
    }

    return 0;
}