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authorTom Gundersen <teg@jklm.no>2014-12-22 00:58:26 +0100
committerTom Gundersen <teg@jklm.no>2014-12-22 20:26:53 +0100
commit2bb4c7e384c31de4727f1330da3f4de2f0bb7784 (patch)
treee6ca2bf55af1be1c20066533ef38f686fc40fc57 /src/shared/utf8.c
parent856d6e09887730f115e43faf9577b479f2beb3c4 (diff)
shared: utf8 - support ucs4 -> utf8
Originally we only supported ucs2, so move the ucs4 version from libsystemd-terminal to shared and use that everywhere.
Diffstat (limited to 'src/shared/utf8.c')
-rw-r--r--src/shared/utf8.c51
1 files changed, 38 insertions, 13 deletions
diff --git a/src/shared/utf8.c b/src/shared/utf8.c
index 03a0abe44b..ab57f4276b 100644
--- a/src/shared/utf8.c
+++ b/src/shared/utf8.c
@@ -263,21 +263,46 @@ char *ascii_is_valid(const char *str) {
return (char*) str;
}
-int utf8_encode_unichar(uint16_t c, char *p) {
- uint8_t *t = (uint8_t*) p;
-
- if (c < 0x80) {
- t[0] = (uint8_t) c;
+/**
+ * utf8_encode_unichar() - Encode single UCS-4 character as UTF-8
+ * @out_utf8: output buffer of at least 4 bytes or NULL
+ * @g: UCS-4 character to encode
+ *
+ * This encodes a single UCS-4 character as UTF-8 and writes it into @out_utf8.
+ * The length of the character is returned. It is not zero-terminated! If the
+ * output buffer is NULL, only the length is returned.
+ *
+ * Returns: The length in bytes that the UTF-8 representation does or would
+ * occupy.
+ */
+size_t utf8_encode_unichar(char *out_utf8, uint32_t g) {
+ if (g < (1 << 7)) {
+ if (out_utf8)
+ out_utf8[0] = g & 0x7f;
return 1;
- } else if (c < 0x800) {
- t[0] = (uint8_t) (0xc0 | (c >> 6));
- t[1] = (uint8_t) (0x80 | (c & 0x3f));
+ } else if (g < (1 << 11)) {
+ if (out_utf8) {
+ out_utf8[0] = 0xc0 | ((g >> 6) & 0x1f);
+ out_utf8[1] = 0x80 | (g & 0x3f);
+ }
return 2;
- } else {
- t[0] = (uint8_t) (0xe0 | (c >> 12));
- t[1] = (uint8_t) (0x80 | ((c >> 6) & 0x3f));
- t[2] = (uint8_t) (0x80 | (c & 0x3f));
+ } else if (g < (1 << 16)) {
+ if (out_utf8) {
+ out_utf8[0] = 0xe0 | ((g >> 12) & 0x0f);
+ out_utf8[1] = 0x80 | ((g >> 6) & 0x3f);
+ out_utf8[2] = 0x80 | (g & 0x3f);
+ }
return 3;
+ } else if (g < (1 << 21)) {
+ if (out_utf8) {
+ out_utf8[0] = 0xf0 | ((g >> 18) & 0x07);
+ out_utf8[1] = 0x80 | ((g >> 12) & 0x3f);
+ out_utf8[2] = 0x80 | ((g >> 6) & 0x3f);
+ out_utf8[3] = 0x80 | (g & 0x3f);
+ }
+ return 4;
+ } else {
+ return 0;
}
}
@@ -290,7 +315,7 @@ char *utf16_to_utf8(const void *s, size_t length) {
return NULL;
for (f = s, t = r; f < (const uint8_t*) s + length; f += 2)
- t += utf8_encode_unichar((f[1] << 8) | f[0], t);
+ t += utf8_encode_unichar(t, (f[1] << 8) | f[0]);
*t = 0;
return r;