fix: consistent usage of bitmask operations on unicode functions

diff --git a/st.c b/st.c
index 16803ec..ac1954e 100644 (file)
--- a/st.c
+++ b/st.c
@@ -150,10 +150,6 @@ enum selection_snap {
        SNAP_LINE = 2
 };
 
-/* bit macro */
-#undef B0
-enum { B0=1, B1=2, B2=4, B3=8, B4=16, B5=32, B6=64, B7=128 };
-
 typedef unsigned char uchar;
 typedef unsigned int uint;
 typedef unsigned long ulong;
@@ -527,17 +523,17 @@ utf8decode(char *s, long *u) {
 
        rtn = 1;
        c = *s;
-       if(~c & B7) { /* 0xxxxxxx */
+       if(~c & 0x80) { /* 0xxxxxxx */
                *u = c;
                return rtn;
-       } else if((c & (B7|B6|B5)) == (B7|B6)) { /* 110xxxxx */
-               *u = c&(B4|B3|B2|B1|B0);
+       } else if((c & 0xE0) == 0xC0) { /* 110xxxxx */
+               *u = c & 0x1F;
                n = 1;
-       } else if((c & (B7|B6|B5|B4)) == (B7|B6|B5)) { /* 1110xxxx */
-               *u = c&(B3|B2|B1|B0);
+       } else if((c & 0xF0) == 0xE0) { /* 1110xxxx */
+               *u = c & 0x0F;
                n = 2;
-       } else if((c & (B7|B6|B5|B4|B3)) == (B7|B6|B5|B4)) { /* 11110xxx */
-               *u = c & (B2|B1|B0);
+       } else if((c & 0xF8) == 0xF0) { /* 11110xxx */
+               *u = c & 0x07;
                n = 3;
        } else {
                goto invalid;
@@ -545,10 +541,10 @@ utf8decode(char *s, long *u) {
 
        for(i = n, ++s; i > 0; --i, ++rtn, ++s) {
                c = *s;
-               if((c & (B7|B6)) != B7) /* 10xxxxxx */
+               if((c & 0xC0) != 0x80) /* 10xxxxxx */
                        goto invalid;
                *u <<= 6;
-               *u |= c & (B5|B4|B3|B2|B1|B0);
+               *u |= c & 0x3F;
        }
 
        if((n == 1 && *u < 0x80) ||
@@ -577,20 +573,20 @@ utf8encode(long *u, char *s) {
                *sp = uc; /* 0xxxxxxx */
                return 1;
        } else if(*u < 0x800) {
-               *sp = (uc >> 6) | (B7|B6); /* 110xxxxx */
+               *sp = (uc >> 6) | 0xC0; /* 110xxxxx */
                n = 1;
        } else if(uc < 0x10000) {
-               *sp = (uc >> 12) | (B7|B6|B5); /* 1110xxxx */
+               *sp = (uc >> 12) | 0xE0; /* 1110xxxx */
                n = 2;
        } else if(uc <= 0x10FFFF) {
-               *sp = (uc >> 18) | (B7|B6|B5|B4); /* 11110xxx */
+               *sp = (uc >> 18) | 0xF0; /* 11110xxx */
                n = 3;
        } else {
                goto invalid;
        }
 
        for(i=n,++sp; i>0; --i,++sp)
-               *sp = ((uc >> 6*(i-1)) & (B5|B4|B3|B2|B1|B0)) | B7; /* 10xxxxxx */
+               *sp = ((uc >> 6*(i-1)) & 0x3F) | 0x80; /* 10xxxxxx */
 
        return n+1;
 invalid:
@@ -613,16 +609,16 @@ isfullutf8(char *s, int b) {
        c3 = (uchar *)++s;
        if(b < 1) {
                return 0;
-       } else if((*c1&(B7|B6|B5)) == (B7|B6) && b == 1) {
+       } else if((*c1 & 0xE0) == 0xC0 && b == 1) {
                return 0;
-       } else if((*c1&(B7|B6|B5|B4)) == (B7|B6|B5) &&
+       } else if((*c1 & 0xF0) == 0xE0 &&
            ((b == 1) ||
-           ((b == 2) && (*c2&(B7|B6)) == B7))) {
+           ((b == 2) && (*c2 & 0xC0) == 0x80))) {
                return 0;
-       } else if((*c1&(B7|B6|B5|B4|B3)) == (B7|B6|B5|B4) &&
+       } else if((*c1 & 0xF8) == 0xF0 &&
            ((b == 1) ||
-           ((b == 2) && (*c2&(B7|B6)) == B7) ||
-           ((b == 3) && (*c2&(B7|B6)) == B7 && (*c3&(B7|B6)) == B7))) {
+           ((b == 2) && (*c2 & 0xC0) == 0x80) ||
+           ((b == 3) && (*c2 & 0xC0) == 0x80 && (*c3 & 0xC0) == 0x80))) {
                return 0;
        } else {
                return 1;
@@ -633,11 +629,11 @@ int
 utf8size(char *s) {
        uchar c = *s;
 
-       if(~c&B7) {
+       if(~c & 0x80) {
                return 1;
-       } else if((c&(B7|B6|B5)) == (B7|B6)) {
+       } else if((c & 0xE0) == 0xC0) {
                return 2;
-       } else if((c&(B7|B6|B5|B4)) == (B7|B6|B5)) {
+       } else if((c & 0xF0) == 0xE0) {
                return 3;
        } else {
                return 4;
@@ -3456,7 +3452,7 @@ kpress(XEvent *ev) {
                if(len == 1 && e->state & Mod1Mask) {
                        if(IS_SET(MODE_8BIT)) {
                                if(*xstr < 0177) {
-                                       c = *xstr | B7;
+                                       c = *xstr | 0x80;
                                        ret = utf8encode(&c, cp);
                                        cp += ret;
                                        len = 0;