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-rw-r--r--code/fe310/eos/unicode.c180
1 files changed, 180 insertions, 0 deletions
diff --git a/code/fe310/eos/unicode.c b/code/fe310/eos/unicode.c
new file mode 100644
index 0000000..2915791
--- /dev/null
+++ b/code/fe310/eos/unicode.c
@@ -0,0 +1,180 @@
+#include "unicode.h"
+
+int utf8_enc(utf32_t ch, utf8_t *str) {
+ if (ch <= 0x7f) {
+ str[0] = ch;
+ return 1;
+ } else if (ch <= 0x7ff) {
+ str[0] = 0xc0 | (ch >> 6);
+ str[1] = 0x80 | (ch & 0x3f);
+ return 2;
+ } else if (ch <= 0xffff) {
+ if ((ch >= 0xd800) && (ch <= 0xdfff)) return UTF_ERR;
+ str[0] = 0xe0 | (ch >> 12);
+ str[1] = 0x80 | ((ch >> 6) & 0x3f);
+ str[2] = 0x80 | (ch & 0x3f);
+ return 3;
+ } else if (ch <= 0x10ffff) {
+ str[0] = 0xf0 | (ch >> 18);
+ str[1] = 0x80 | ((ch >> 12) & 0x3f);
+ str[2] = 0x80 | ((ch >> 6) & 0x3f);
+ str[3] = 0x80 | (ch & 0x3f);
+ return 4;
+ } else {
+ return UTF_ERR;
+ }
+}
+
+int utf8_dec(utf8_t *str, utf32_t *ch) {
+ if ((str[0] & 0x80) == 0x00) {
+ *ch = str[0];
+ return 1;
+ } else if ((str[0] & 0xe0) == 0xc0) {
+ if ((str[1] & 0xc0) != 0x80) return UTF_ERR;
+ *ch = (utf32_t)(str[0] & 0x1f) << 6;
+ *ch |= (utf32_t)(str[1] & 0x3f);
+ if (*ch < 0x80) return UTF_ERR;
+ return 2;
+ } else if ((str[0] & 0xf0) == 0xe0) {
+ if (((str[1] & 0xc0) != 0x80) || ((str[2] & 0xc0) != 0x80)) return UTF_ERR;
+ *ch = (utf32_t)(str[0] & 0x0f) << 12;
+ *ch |= (utf32_t)(str[1] & 0x3f) << 6;
+ *ch |= (utf32_t)(str[2] & 0x3f);
+ if ((*ch >= 0xd800) && (*ch <= 0xdfff)) return UTF_ERR;
+ if (*ch < 0x800) return UTF_ERR;
+ return 3;
+ } else if ((str[0] & 0xf8) == 0xf0) {
+ if (((str[1] & 0xc0) != 0x80) || ((str[2] & 0xc0) != 0x80) || ((str[3] & 0xc0) != 0x80)) return UTF_ERR;
+ *ch = (utf32_t)(str[0] & 0x07) << 18;
+ *ch |= (utf32_t)(str[1] & 0x0f) << 12;
+ *ch |= (utf32_t)(str[2] & 0x3f) << 6;
+ *ch |= (utf32_t)(str[3] & 0x3f);
+ if (*ch < 0x010000) return UTF_ERR;
+ if (*ch > 0x10ffff) return UTF_ERR;
+ return 4;
+ } else {
+ return UTF_ERR;
+ }
+}
+
+int utf8_seek(utf8_t *str, int off, utf32_t *ch) {
+ int i;
+ int len = 0;
+
+ if (off < 0) {
+ off = -off;
+ for (i=0; i<off; i++) {
+ len--;
+ while ((str[len] & 0xc0) == 0x80) len--;
+ }
+ } else {
+ for (i=0; i<off; i++) {
+ if ((str[len] & 0x80) == 0x00) {
+ len += 1;
+ } else if ((str[0] & 0xe0) == 0xc0) {
+ len += 2;
+ } else if ((str[0] & 0xf0) == 0xe0) {
+ len += 3;
+ } else if ((str[0] & 0xf8) == 0xf0) {
+ len += 4;
+ }
+ }
+ }
+ utf8_dec(str + len, ch);
+ return len;
+}
+
+int utf8_verify(utf8_t *str, int str_size, int *str_len) {
+ utf32_t ch;
+ uint8_t ch_l;
+ int len = 0;
+
+ while (len < str_size) {
+ if (str_size - len < 4) {
+ if (((str[len] & 0xf8) == 0xf0) ||
+ (((str[len] & 0xf0) == 0xe0) && (str_size - len < 3)) ||
+ (((str[len] & 0xe0) == 0xc0) && (str_size - len < 2))) {
+ break;
+ }
+ }
+ ch_l = utf8_dec(str + len, &ch);
+ if (ch_l > 0) {
+ if (ch == 0) {
+ *str_len = len;
+ return UTF_OK;
+ }
+ len += ch_l;
+ } else {
+ break;
+ }
+ }
+ *str_len = len;
+ return UTF_ERR;
+}
+
+int utf16_enc(utf32_t ch, uint8_t *str) {
+ if (ch <= 0xffff) {
+ if ((ch >= 0xd800) && (ch <= 0xdfff)) return UTF_ERR;
+ str[0] = ch >> 8;
+ str[1] = ch & 0xff;
+ return 2;
+ } else if (ch <= 0x10ffff) {
+ uint16_t hi;
+ uint16_t lo;
+
+ ch -= 0x10000;
+ hi = (ch >> 10) + 0xd800;
+ lo = (ch & 0x3ff) + 0xdc00;
+ str[0] = hi >> 8;
+ str[1] = hi & 0xff;
+ str[2] = lo >> 8;
+ str[3] = lo & 0xff;
+ return 4;
+ } else {
+ return UTF_ERR;
+ }
+}
+
+int utf16_dec(uint8_t *str, utf32_t *ch) {
+ *ch = (str[0] << 8) | str[1];
+ if ((*ch >= 0xd800) && (*ch <= 0xdfff)) {
+ uint16_t hi = *ch;
+ uint16_t lo;
+
+ if (hi > 0xdbff) return UTF_ERR;
+ lo = (str[2] << 8) | str[3];
+ if ((lo < 0xdc00) || (lo > 0xdfff)) return UTF_ERR;
+ *ch = (((hi - 0xd800) << 10) | (lo - 0xdc00)) + 0x10000;
+ return 4;
+ } else {
+ return 2;
+ }
+}
+
+int utf16_seek(uint8_t *str, int off, utf32_t *ch) {
+ int i;
+ int len = 0;
+ uint16_t cu;
+
+ if (off < 0) {
+ off = -off;
+ for (i=0; i<off; i++) {
+ len -= 2;
+ cu = (str[len] << 8) | str[len + 1];
+ if ((cu >= 0xdc00) && (cu <= 0xdfff)) {
+ len -= 2;
+ }
+ }
+ } else {
+ for (i=0; i<off; i++) {
+ cu = (str[len] << 8) | str[len + 1];
+ if ((cu >= 0xd800) && (cu <= 0xdbff)) {
+ len += 4;
+ } else {
+ len += 2;
+ }
+ }
+ }
+ utf16_dec(str + len, ch);
+ return len;
+}