+ return s;
+}
+
+size_t
+utf8decode(const char *c, Rune *u, size_t clen)
+{
+ size_t i, j, len, type;
+ Rune udecoded;
+
+ *u = UTF_INVALID;
+ if (!clen)
+ return 0;
+ udecoded = utf8decodebyte(c[0], &len);
+ if (!BETWEEN(len, 1, UTF_SIZ))
+ return 1;
+ 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;
+}
+
+Rune
+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;
+}
+
+size_t
+utf8encode(Rune u, char *c)
+{
+ size_t len, i;
+
+ len = utf8validate(&u, 0);
+ if (len > UTF_SIZ)
+ return 0;
+
+ for (i = len - 1; i != 0; --i) {
+ c[i] = utf8encodebyte(u, 0);
+ u >>= 6;
+ }
+ c[0] = utf8encodebyte(u, len);
+
+ return len;
+}
+
+char
+utf8encodebyte(Rune u, size_t i)
+{
+ return utfbyte[i] | (u & ~utfmask[i]);
+}
+
+char *
+utf8strchr(char *s, Rune u)
+{
+ Rune r;
+ size_t i, j, len;
+
+ len = strlen(s);
+ for (i = 0, j = 0; i < len; i += j) {
+ if (!(j = utf8decode(&s[i], &r, len - i)))
+ break;
+ if (r == u)
+ return &(s[i]);
+ }
+
+ return NULL;
+}
+
+size_t
+utf8validate(Rune *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 const char base64_digits[] = {
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 62, 0, 0, 0,
+ 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 0, 0, 0, -1, 0, 0, 0, 0, 1,
+ 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,
+ 22, 23, 24, 25, 0, 0, 0, 0, 0, 0, 26, 27, 28, 29, 30, 31, 32, 33, 34,
+ 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+};
+
+char
+base64dec_getc(const char **src)
+{
+ while (**src && !isprint(**src)) (*src)++;
+ return *((*src)++);
+}
+
+char *
+base64dec(const char *src)
+{
+ size_t in_len = strlen(src);
+ char *result, *dst;
+
+ if (in_len % 4)
+ in_len += 4 - (in_len % 4);
+ result = dst = xmalloc(in_len / 4 * 3 + 1);
+ while (*src) {
+ int a = base64_digits[(unsigned char) base64dec_getc(&src)];
+ int b = base64_digits[(unsigned char) base64dec_getc(&src)];
+ int c = base64_digits[(unsigned char) base64dec_getc(&src)];
+ int d = base64_digits[(unsigned char) base64dec_getc(&src)];
+
+ *dst++ = (a << 2) | ((b & 0x30) >> 4);
+ if (c == -1)
+ break;
+ *dst++ = ((b & 0x0f) << 4) | ((c & 0x3c) >> 2);
+ if (d == -1)
+ break;
+ *dst++ = ((c & 0x03) << 6) | d;
+ }
+ *dst = '\0';
+ return result;
+}
+
+void
+selinit(void)
+{
+ sel.mode = SEL_IDLE;
+ sel.snap = 0;
+ sel.ob.x = -1;
+}
+
+int
+tlinelen(int y)
+{
+ int i = term.col;
+
+ if (term.line[y][i - 1].mode & ATTR_WRAP)
+ return i;
+
+ while (i > 0 && term.line[y][i - 1].u == ' ')
+ --i;
+
+ return i;
+}
+
+void
+selstart(int col, int row, int snap)
+{
+ selclear();
+ sel.mode = SEL_EMPTY;
+ sel.type = SEL_REGULAR;
+ sel.snap = snap;
+ sel.oe.x = sel.ob.x = col;
+ sel.oe.y = sel.ob.y = row;
+ selnormalize();
+
+ if (sel.snap != 0)
+ sel.mode = SEL_READY;
+ tsetdirt(sel.nb.y, sel.ne.y);
+}
+
+void
+selextend(int col, int row, int type, int done)
+{
+ int oldey, oldex, oldsby, oldsey, oldtype;
+
+ if (!sel.mode)
+ return;
+ if (done && sel.mode == SEL_EMPTY) {
+ selclear();
+ return;
+ }
+
+ oldey = sel.oe.y;
+ oldex = sel.oe.x;
+ oldsby = sel.nb.y;
+ oldsey = sel.ne.y;
+ oldtype = sel.type;
+
+ sel.alt = IS_SET(MODE_ALTSCREEN);
+ sel.oe.x = col;
+ sel.oe.y = row;
+ selnormalize();
+ sel.type = type;
+
+ if (oldey != sel.oe.y || oldex != sel.oe.x || oldtype != sel.type)
+ tsetdirt(MIN(sel.nb.y, oldsby), MAX(sel.ne.y, oldsey));
+
+ sel.mode = done ? SEL_IDLE : SEL_READY;
+}
+
+void
+selnormalize(void)
+{
+ int i;
+
+ if (sel.type == SEL_REGULAR && sel.ob.y != sel.oe.y) {
+ sel.nb.x = sel.ob.y < sel.oe.y ? sel.ob.x : sel.oe.x;
+ sel.ne.x = sel.ob.y < sel.oe.y ? sel.oe.x : sel.ob.x;
+ } else {
+ sel.nb.x = MIN(sel.ob.x, sel.oe.x);
+ sel.ne.x = MAX(sel.ob.x, sel.oe.x);
+ }
+ sel.nb.y = MIN(sel.ob.y, sel.oe.y);
+ sel.ne.y = MAX(sel.ob.y, sel.oe.y);
+
+ selsnap(&sel.nb.x, &sel.nb.y, -1);
+ selsnap(&sel.ne.x, &sel.ne.y, +1);
+
+ /* expand selection over line breaks */
+ if (sel.type == SEL_RECTANGULAR)
+ return;
+ i = tlinelen(sel.nb.y);
+ if (i < sel.nb.x)
+ sel.nb.x = i;
+ if (tlinelen(sel.ne.y) <= sel.ne.x)
+ sel.ne.x = term.col - 1;
+}
+
+int
+selected(int x, int y)
+{
+ if (sel.mode == SEL_EMPTY || sel.ob.x == -1 ||
+ sel.alt != IS_SET(MODE_ALTSCREEN))
+ return 0;
+
+ if (sel.type == SEL_RECTANGULAR)
+ return BETWEEN(y, sel.nb.y, sel.ne.y)
+ && BETWEEN(x, sel.nb.x, sel.ne.x);
+
+ return BETWEEN(y, sel.nb.y, sel.ne.y)
+ && (y != sel.nb.y || x >= sel.nb.x)
+ && (y != sel.ne.y || x <= sel.ne.x);
+}
+
+void
+selsnap(int *x, int *y, int direction)
+{
+ int newx, newy, xt, yt;
+ int delim, prevdelim;
+ Glyph *gp, *prevgp;
+
+ switch (sel.snap) {
+ case SNAP_WORD:
+ /*
+ * Snap around if the word wraps around at the end or
+ * beginning of a line.
+ */
+ prevgp = &term.line[*y][*x];
+ prevdelim = ISDELIM(prevgp->u);
+ for (;;) {
+ newx = *x + direction;
+ newy = *y;
+ if (!BETWEEN(newx, 0, term.col - 1)) {
+ newy += direction;
+ newx = (newx + term.col) % term.col;
+ if (!BETWEEN(newy, 0, term.row - 1))
+ break;
+
+ if (direction > 0)
+ yt = *y, xt = *x;
+ else
+ yt = newy, xt = newx;
+ if (!(term.line[yt][xt].mode & ATTR_WRAP))
+ break;
+ }
+
+ if (newx >= tlinelen(newy))
+ break;
+
+ gp = &term.line[newy][newx];
+ delim = ISDELIM(gp->u);
+ if (!(gp->mode & ATTR_WDUMMY) && (delim != prevdelim
+ || (delim && gp->u != prevgp->u)))
+ break;
+
+ *x = newx;
+ *y = newy;
+ prevgp = gp;
+ prevdelim = delim;
+ }
+ break;
+ case SNAP_LINE:
+ /*
+ * Snap around if the the previous line or the current one
+ * has set ATTR_WRAP at its end. Then the whole next or
+ * previous line will be selected.
+ */
+ *x = (direction < 0) ? 0 : term.col - 1;
+ if (direction < 0) {
+ for (; *y > 0; *y += direction) {
+ if (!(term.line[*y-1][term.col-1].mode
+ & ATTR_WRAP)) {
+ break;
+ }
+ }
+ } else if (direction > 0) {
+ for (; *y < term.row-1; *y += direction) {
+ if (!(term.line[*y][term.col-1].mode
+ & ATTR_WRAP)) {
+ break;
+ }
+ }
+ }
+ break;
+ }
+}
+
+char *
+getsel(void)
+{
+ char *str, *ptr;
+ int y, bufsize, lastx, linelen;
+ Glyph *gp, *last;
+
+ if (sel.ob.x == -1)
+ return NULL;
+
+ bufsize = (term.col+1) * (sel.ne.y-sel.nb.y+1) * UTF_SIZ;
+ ptr = str = xmalloc(bufsize);
+
+ /* append every set & selected glyph to the selection */
+ for (y = sel.nb.y; y <= sel.ne.y; y++) {
+ if ((linelen = tlinelen(y)) == 0) {
+ *ptr++ = '\n';
+ continue;
+ }
+
+ if (sel.type == SEL_RECTANGULAR) {
+ gp = &term.line[y][sel.nb.x];
+ lastx = sel.ne.x;
+ } else {
+ gp = &term.line[y][sel.nb.y == y ? sel.nb.x : 0];
+ lastx = (sel.ne.y == y) ? sel.ne.x : term.col-1;
+ }
+ last = &term.line[y][MIN(lastx, linelen-1)];
+ while (last >= gp && last->u == ' ')
+ --last;
+
+ for ( ; gp <= last; ++gp) {
+ if (gp->mode & ATTR_WDUMMY)
+ continue;
+
+ ptr += utf8encode(gp->u, ptr);
+ }
+
+ /*
+ * Copy and pasting of line endings is inconsistent
+ * in the inconsistent terminal and GUI world.
+ * The best solution seems like to produce '\n' when
+ * something is copied from st and convert '\n' to
+ * '\r', when something to be pasted is received by
+ * st.
+ * FIXME: Fix the computer world.
+ */
+ if ((y < sel.ne.y || lastx >= linelen) && !(last->mode & ATTR_WRAP))
+ *ptr++ = '\n';
+ }
+ *ptr = 0;
+ return str;
+}
+
+void
+selclear(void)
+{
+ if (sel.ob.x == -1)
+ return;
+ sel.mode = SEL_IDLE;
+ sel.ob.x = -1;
+ tsetdirt(sel.nb.y, sel.ne.y);
+}