mbcs.c

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

void mb_to_uc_fallback(
		const char* inbuf,
		size_t inbufsize,
		void (*write_replacement) (const unsigned int *buf, size_t buflen, void* callback_arg),
		void* callback_arg,
		void* data) {
	printf("mb_to_uc_fallback\n");
}

void uc_to_mb_fallback(
		unsigned int code,
		void (*write_replacement) (const char *buf, size_t buflen, void* callback_arg),
		void* callback_arg,
		void* data) {
	printf("uc_to_mb_fallback\n");
}

void mb_to_wc_fallback(
		const char* inbuf, size_t inbufsize,
		void (*write_replacement) (const wchar_t *buf, size_t buflen, void* callback_arg),
		void* callback_arg,
		void* data) {
	printf("mb_to_wc_fallback\n");
}

void wc_to_mb_fallback(
		wchar_t code,
		void (*write_replacement) (const char *buf, size_t buflen, void* callback_arg),
		void* callback_arg,
		void* data) {
	printf("wc_to_mb_fallback\n");
}

int code_convert(
		const char *from_chrset,
		const char *to_chrset,
		const char *inbuf,
		int in_len,
		char *outbuf,
		int out_len)
{
	iconv_t cd;
	struct iconv_fallbacks fallback = {
		mb_to_uc_fallback,
		uc_to_mb_fallback,
		mb_to_wc_fallback,
		wc_to_mb_fallback,
		NULL // data
	};

	cd = iconv_open(to_chrset, from_chrset);
	if (cd == 0) {
		printf("can't open charset %s !\n", to_chrset);
		return -1;
	}
	iconvctl(cd, ICONV_SET_FALLBACKS, &fallback);
	memset(outbuf, 0, out_len);
	if (iconv(cd, (char**)&inbuf, &in_len, &outbuf, &out_len ) == -1) {
		fprintf(stderr, "%s\n", strerror(errno));
		return -1;
	}
	iconv_close(cd);
	return 0;
}

int main(void) {
	// あいう～
	const char* from = "\xe3\x81\x82\xe3\x81\x84\xe3\x81\x86\xef\xbd\x9e";
	char to[256] = {0};

	code_convert("utf-8", "char", from, strlen(from), to, sizeof(to));
	printf("%s\n", to);

	return 0;
}