commit: 45b808b88ee63f21a188800ba3473a24a3c4b987
parent: 71328cbcdc88f4fdfbb62d8c0324938e245c8971
Author: Damian Okrasa <dokrasa@gmail.com>
Date: Tue, 25 Mar 2014 20:20:26 +0100
new utf decoder
This patch replaces current utf decoder with a new one, which is ~50
lines shorter and should be easier to understand. Parsing 5 and 6
sequences, if necessary, requires trivial modification of UTF_SIZ
constant and utfbyte, utfmask, utfmin, utfmax arrays.
Diffstat:
| M | st.c | 214 | ++++++++++++++++++++++++++++++------------------------------------------------- |
1 file changed, 81 insertions(+), 133 deletions(-)
diff --git a/st.c b/st.c
@@ -55,6 +55,7 @@ char *argv0;
#define XEMBED_FOCUS_OUT 5
/* Arbitrary sizes */
+#define UTF_INVALID 0xFFFD
#define UTF_SIZ 4
#define ESC_BUF_SIZ (128*UTF_SIZ)
#define ESC_ARG_SIZ 16
@@ -442,10 +443,12 @@ static void selcopy(void);
static void selscroll(int, int);
static void selsnap(int, int *, int *, int);
-static int utf8decode(char *, long *);
-static int utf8encode(long *, char *);
-static int utf8size(char *);
-static int isfullutf8(char *, int);
+static size_t utf8decode(char *, long *, size_t);
+static long utf8decodebyte(char, size_t *);
+static size_t utf8encode(long, char *, size_t);
+static char utf8encodebyte(long, size_t);
+static size_t utf8len(char *);
+static size_t utf8validate(long *, size_t);
static ssize_t xwrite(int, char *, size_t);
static void *xmalloc(size_t);
@@ -490,6 +493,11 @@ static int oldbutton = 3; /* button event on startup: 3 = release */
static char *usedfont = NULL;
static double usedfontsize = 0;
+static uchar utfbyte[UTF_SIZ + 1] = {0x80, 0, 0xC0, 0xE0, 0xF0};
+static uchar utfmask[UTF_SIZ + 1] = {0xC0, 0x80, 0xE0, 0xF0, 0xF8};
+static long utfmin[UTF_SIZ + 1] = { 0, 0, 0x80, 0x800, 0x10000};
+static long utfmax[UTF_SIZ + 1] = {0x10FFFF, 0x7F, 0x7FF, 0xFFFF, 0x10FFFF};
+
/* Font Ring Cache */
enum {
FRC_NORMAL,
@@ -549,128 +557,69 @@ xstrdup(char *s) {
return p;
}
-int
-utf8decode(char *s, long *u) {
- uchar c;
- int i, n, rtn;
-
- rtn = 1;
- c = *s;
- if(~c & 0x80) { /* 0xxxxxxx */
- *u = c;
- return rtn;
- } else if((c & 0xE0) == 0xC0) { /* 110xxxxx */
- *u = c & 0x1F;
- n = 1;
- } else if((c & 0xF0) == 0xE0) { /* 1110xxxx */
- *u = c & 0x0F;
- n = 2;
- } else if((c & 0xF8) == 0xF0) { /* 11110xxx */
- *u = c & 0x07;
- n = 3;
- } else {
- goto invalid;
- }
-
- for(i = n, ++s; i > 0; --i, ++rtn, ++s) {
- c = *s;
- if((c & 0xC0) != 0x80) /* 10xxxxxx */
- goto invalid;
- *u <<= 6;
- *u |= c & 0x3F;
- }
-
- if((n == 1 && *u < 0x80) ||
- (n == 2 && *u < 0x800) ||
- (n == 3 && *u < 0x10000) ||
- (*u >= 0xD800 && *u <= 0xDFFF)) {
- goto invalid;
- }
-
- return rtn;
-invalid:
- *u = 0xFFFD;
-
- return rtn;
-}
+size_t
+utf8decode(char *c, long *u, size_t clen) {
+ size_t i, j, len, type;
+ long udecoded;
-int
-utf8encode(long *u, char *s) {
- uchar *sp;
- ulong uc;
- int i, n;
-
- sp = (uchar *)s;
- uc = *u;
- if(uc < 0x80) {
- *sp = uc; /* 0xxxxxxx */
+ *u = UTF_INVALID;
+ if(!clen)
+ return 0;
+ udecoded = utf8decodebyte(c[0], &len);
+ if(!BETWEEN(len, 1, UTF_SIZ))
return 1;
- } else if(*u < 0x800) {
- *sp = (uc >> 6) | 0xC0; /* 110xxxxx */
- n = 1;
- } else if(uc < 0x10000) {
- *sp = (uc >> 12) | 0xE0; /* 1110xxxx */
- n = 2;
- } else if(uc <= 0x10FFFF) {
- *sp = (uc >> 18) | 0xF0; /* 11110xxx */
- n = 3;
- } else {
- goto invalid;
+ for(i = 1, j = 1; i < clen && j < len; ++i, ++j) {
+ udecoded = (udecoded << 6) | utf8decodebyte(c[i], &type);
+ if(type != 0)
+ return j;
}
+ if(j < len)
+ return 0;
+ *u = udecoded;
+ utf8validate(u, len);
+ return len;
+}
- for(i=n,++sp; i>0; --i,++sp)
- *sp = ((uc >> 6*(i-1)) & 0x3F) | 0x80; /* 10xxxxxx */
-
- return n+1;
-invalid:
- /* U+FFFD */
- *s++ = '\xEF';
- *s++ = '\xBF';
- *s = '\xBD';
-
- return 3;
+long
+utf8decodebyte(char c, size_t *i) {
+ for(*i = 0; *i < LEN(utfmask); ++(*i))
+ if(((uchar)c & utfmask[*i]) == utfbyte[*i])
+ return (uchar)c & ~utfmask[*i];
+ return 0;
}
-/* use this if your buffer is less than UTF_SIZ, it returns 1 if you can decode
- UTF-8 otherwise return 0 */
-int
-isfullutf8(char *s, int b) {
- uchar *c1, *c2, *c3;
+size_t
+utf8encode(long u, char *c, size_t clen) {
+ size_t len, i;
- c1 = (uchar *)s;
- c2 = (uchar *)++s;
- c3 = (uchar *)++s;
- if(b < 1) {
+ len = utf8validate(&u, 0);
+ if(clen < len)
return 0;
- } else if((*c1 & 0xE0) == 0xC0 && b == 1) {
- return 0;
- } else if((*c1 & 0xF0) == 0xE0 &&
- ((b == 1) ||
- ((b == 2) && (*c2 & 0xC0) == 0x80))) {
- return 0;
- } else if((*c1 & 0xF8) == 0xF0 &&
- ((b == 1) ||
- ((b == 2) && (*c2 & 0xC0) == 0x80) ||
- ((b == 3) && (*c2 & 0xC0) == 0x80 && (*c3 & 0xC0) == 0x80))) {
- return 0;
- } else {
- return 1;
+ for(i = len - 1; i != 0; --i) {
+ c[i] = utf8encodebyte(u, 0);
+ u >>= 6;
}
+ c[0] = utf8encodebyte(u, len);
+ return len;
}
-int
-utf8size(char *s) {
- uchar c = *s;
+char
+utf8encodebyte(long u, size_t i) {
+ return utfbyte[i] | (u & ~utfmask[i]);
+}
- if(~c & 0x80) {
- return 1;
- } else if((c & 0xE0) == 0xC0) {
- return 2;
- } else if((c & 0xF0) == 0xE0) {
- return 3;
- } else {
- return 4;
- }
+size_t
+utf8len(char *c) {
+ return utf8decode(c, &(long){0}, UTF_SIZ);
+}
+
+size_t
+utf8validate(long *u, size_t i) {
+ if(!BETWEEN(*u, utfmin[i], utfmax[i]) || BETWEEN(*u, 0xD800, 0xDFFF))
+ *u = UTF_INVALID;
+ for(i = 1; *u > utfmax[i]; ++i)
+ ;
+ return i;
}
static void
@@ -984,7 +933,7 @@ getsel(void) {
if(!selected(x, y) || (gp->mode & ATTR_WDUMMY))
continue;
- size = utf8size(gp->c);
+ size = utf8len(gp->c);
memcpy(ptr, gp->c, size);
ptr += size;
}
@@ -1298,7 +1247,7 @@ ttyread(void) {
char *ptr;
char s[UTF_SIZ];
int charsize; /* size of utf8 char in bytes */
- long utf8c;
+ long unicodep;
int ret;
/* append read bytes to unprocessed bytes */
@@ -1308,9 +1257,8 @@ ttyread(void) {
/* process every complete utf8 char */
buflen += ret;
ptr = buf;
- while(buflen >= UTF_SIZ || isfullutf8(ptr,buflen)) {
- charsize = utf8decode(ptr, &utf8c);
- utf8encode(&utf8c, s);
+ while(charsize = utf8decode(ptr, &unicodep, buflen)) {
+ utf8encode(unicodep, s, UTF_SIZ);
tputc(s, charsize);
ptr += charsize;
buflen -= charsize;
@@ -2414,14 +2362,14 @@ void
tputc(char *c, int len) {
uchar ascii = *c;
bool control = ascii < '\x20' || ascii == 0177;
- long u8char;
+ long unicodep;
int width;
if(len == 1) {
width = 1;
} else {
- utf8decode(c, &u8char);
- width = wcwidth(u8char);
+ utf8decode(c, &unicodep, UTF_SIZ);
+ width = wcwidth(unicodep);
}
if(IS_SET(MODE_PRINT))
@@ -3150,7 +3098,7 @@ xdraws(char *s, Glyph base, int x, int y, int charlen, int bytelen) {
int frcflags;
int u8fl, u8fblen, u8cblen, doesexist;
char *u8c, *u8fs;
- long u8char;
+ long unicodep;
Font *font = &dc.font;
FcResult fcres;
FcPattern *fcpattern, *fontpattern;
@@ -3293,11 +3241,11 @@ xdraws(char *s, Glyph base, int x, int y, int charlen, int bytelen) {
oneatatime = font->width != xw.cw;
for(;;) {
u8c = s;
- u8cblen = utf8decode(s, &u8char);
+ u8cblen = utf8decode(s, &unicodep, UTF_SIZ);
s += u8cblen;
bytelen -= u8cblen;
- doesexist = XftCharExists(xw.dpy, font->match, u8char);
+ doesexist = XftCharExists(xw.dpy, font->match, unicodep);
if(oneatatime || !doesexist || bytelen <= 0) {
if(oneatatime || bytelen <= 0) {
if(doesexist) {
@@ -3329,7 +3277,7 @@ xdraws(char *s, Glyph base, int x, int y, int charlen, int bytelen) {
/* Search the font cache. */
for(i = 0; i < frclen; i++) {
- if(XftCharExists(xw.dpy, frc[i].font, u8char)
+ if(XftCharExists(xw.dpy, frc[i].font, unicodep)
&& frc[i].flags == frcflags) {
break;
}
@@ -3351,7 +3299,7 @@ xdraws(char *s, Glyph base, int x, int y, int charlen, int bytelen) {
fcpattern = FcPatternDuplicate(font->pattern);
fccharset = FcCharSetCreate();
- FcCharSetAddChar(fccharset, u8char);
+ FcCharSetAddChar(fccharset, unicodep);
FcPatternAddCharSet(fcpattern, FC_CHARSET,
fccharset);
FcPatternAddBool(fcpattern, FC_SCALABLE,
@@ -3387,7 +3335,7 @@ xdraws(char *s, Glyph base, int x, int y, int charlen, int bytelen) {
xp, winy + frc[i].font->ascent,
(FcChar8 *)u8c, u8cblen);
- xp += xw.cw * wcwidth(u8char);
+ xp += xw.cw * wcwidth(unicodep);
}
/*
@@ -3430,7 +3378,7 @@ xdrawcursor(void) {
memcpy(g.c, term.line[term.c.y][term.c.x].c, UTF_SIZ);
/* remove the old cursor */
- sl = utf8size(term.line[oldy][oldx].c);
+ sl = utf8len(term.line[oldy][oldx].c);
width = (term.line[oldy][oldx].mode & ATTR_WIDE)? 2 : 1;
xdraws(term.line[oldy][oldx].c, term.line[oldy][oldx], oldx,
oldy, width, sl);
@@ -3444,7 +3392,7 @@ xdrawcursor(void) {
g.bg = defaultfg;
}
- sl = utf8size(g.c);
+ sl = utf8len(g.c);
width = (term.line[term.c.y][curx].mode & ATTR_WIDE)\
? 2 : 1;
xdraws(g.c, g, term.c.x, term.c.y, width, sl);
@@ -3516,7 +3464,7 @@ drawregion(int x1, int y1, int x2, int y2) {
Glyph base, new;
char buf[DRAW_BUF_SIZ];
bool ena_sel = sel.ob.x != -1;
- long u8char;
+ long unicodep;
if(sel.alt ^ IS_SET(MODE_ALTSCREEN))
ena_sel = 0;
@@ -3548,7 +3496,7 @@ drawregion(int x1, int y1, int x2, int y2) {
base = new;
}
- sl = utf8decode(new.c, &u8char);
+ sl = utf8decode(new.c, &unicodep, UTF_SIZ);
memcpy(buf+ib, new.c, sl);
ib += sl;
ic += (new.mode & ATTR_WIDE)? 2 : 1;
@@ -3707,7 +3655,7 @@ kpress(XEvent *ev) {
if(IS_SET(MODE_8BIT)) {
if(*buf < 0177) {
c = *buf | 0x80;
- len = utf8encode(&c, buf);
+ len = utf8encode(c, buf, UTF_SIZ);
}
} else {
buf[1] = buf[0];
