diff options
Diffstat (limited to 'tools/plink/ldisc.c')
| -rw-r--r-- | tools/plink/ldisc.c | 336 |
1 files changed, 336 insertions, 0 deletions
diff --git a/tools/plink/ldisc.c b/tools/plink/ldisc.c new file mode 100644 index 000000000..20fa3c568 --- /dev/null +++ b/tools/plink/ldisc.c @@ -0,0 +1,336 @@ +/*
+ * ldisc.c: PuTTY line discipline. Sits between the input coming
+ * from keypresses in the window, and the output channel leading to
+ * the back end. Implements echo and/or local line editing,
+ * depending on what's currently configured.
+ */
+
+#include <stdio.h>
+#include <ctype.h>
+
+#include "putty.h"
+#include "terminal.h"
+#include "ldisc.h"
+
+#define ECHOING (ldisc->cfg->localecho == FORCE_ON || \
+ (ldisc->cfg->localecho == AUTO && \
+ (ldisc->back->ldisc(ldisc->backhandle, LD_ECHO) || \
+ term_ldisc(ldisc->term, LD_ECHO))))
+#define EDITING (ldisc->cfg->localedit == FORCE_ON || \
+ (ldisc->cfg->localedit == AUTO && \
+ (ldisc->back->ldisc(ldisc->backhandle, LD_EDIT) || \
+ term_ldisc(ldisc->term, LD_EDIT))))
+
+static void c_write(Ldisc ldisc, char *buf, int len)
+{
+ from_backend(ldisc->frontend, 0, buf, len);
+}
+
+static int plen(Ldisc ldisc, unsigned char c)
+{
+ if ((c >= 32 && c <= 126) || (c >= 160 && !in_utf(ldisc->term)))
+ return 1;
+ else if (c < 128)
+ return 2; /* ^x for some x */
+ else if (in_utf(ldisc->term) && c >= 0xC0)
+ return 1; /* UTF-8 introducer character
+ * (FIXME: combining / wide chars) */
+ else if (in_utf(ldisc->term) && c >= 0x80 && c < 0xC0)
+ return 0; /* UTF-8 followup character */
+ else
+ return 4; /* <XY> hex representation */
+}
+
+static void pwrite(Ldisc ldisc, unsigned char c)
+{
+ if ((c >= 32 && c <= 126) ||
+ (!in_utf(ldisc->term) && c >= 0xA0) ||
+ (in_utf(ldisc->term) && c >= 0x80)) {
+ c_write(ldisc, (char *)&c, 1);
+ } else if (c < 128) {
+ char cc[2];
+ cc[1] = (c == 127 ? '?' : c + 0x40);
+ cc[0] = '^';
+ c_write(ldisc, cc, 2);
+ } else {
+ char cc[5];
+ sprintf(cc, "<%02X>", c);
+ c_write(ldisc, cc, 4);
+ }
+}
+
+static int char_start(Ldisc ldisc, unsigned char c)
+{
+ if (in_utf(ldisc->term))
+ return (c < 0x80 || c >= 0xC0);
+ else
+ return 1;
+}
+
+static void bsb(Ldisc ldisc, int n)
+{
+ while (n--)
+ c_write(ldisc, "\010 \010", 3);
+}
+
+#define CTRL(x) (x^'@')
+#define KCTRL(x) ((x^'@') | 0x100)
+
+void *ldisc_create(Config *mycfg, Terminal *term,
+ Backend *back, void *backhandle,
+ void *frontend)
+{
+ Ldisc ldisc = snew(struct ldisc_tag);
+
+ ldisc->buf = NULL;
+ ldisc->buflen = 0;
+ ldisc->bufsiz = 0;
+ ldisc->quotenext = 0;
+
+ ldisc->cfg = mycfg;
+ ldisc->back = back;
+ ldisc->backhandle = backhandle;
+ ldisc->term = term;
+ ldisc->frontend = frontend;
+
+ /* Link ourselves into the backend and the terminal */
+ if (term)
+ term->ldisc = ldisc;
+ if (back)
+ back->provide_ldisc(backhandle, ldisc);
+
+ return ldisc;
+}
+
+void ldisc_free(void *handle)
+{
+ Ldisc ldisc = (Ldisc) handle;
+
+ if (ldisc->term)
+ ldisc->term->ldisc = NULL;
+ if (ldisc->back)
+ ldisc->back->provide_ldisc(ldisc->backhandle, NULL);
+ if (ldisc->buf)
+ sfree(ldisc->buf);
+ sfree(ldisc);
+}
+
+void ldisc_send(void *handle, char *buf, int len, int interactive)
+{
+ Ldisc ldisc = (Ldisc) handle;
+ int keyflag = 0;
+ /*
+ * Called with len=0 when the options change. We must inform
+ * the front end in case it needs to know.
+ */
+ if (len == 0) {
+ ldisc_update(ldisc->frontend, ECHOING, EDITING);
+ return;
+ }
+ /*
+ * Notify the front end that something was pressed, in case
+ * it's depending on finding out (e.g. keypress termination for
+ * Close On Exit).
+ */
+ frontend_keypress(ldisc->frontend);
+
+ /*
+ * Less than zero means null terminated special string.
+ */
+ if (len < 0) {
+ len = strlen(buf);
+ keyflag = KCTRL('@');
+ }
+ /*
+ * Either perform local editing, or just send characters.
+ */
+ if (EDITING) {
+ while (len--) {
+ int c;
+ c = *buf++ + keyflag;
+ if (!interactive && c == '\r')
+ c += KCTRL('@');
+ switch (ldisc->quotenext ? ' ' : c) {
+ /*
+ * ^h/^?: delete, and output BSBs, to return to
+ * last character boundary (in UTF-8 mode this may
+ * be more than one byte)
+ * ^w: delete, and output BSBs, to return to last
+ * space/nonspace boundary
+ * ^u: delete, and output BSBs, to return to BOL
+ * ^c: Do a ^u then send a telnet IP
+ * ^z: Do a ^u then send a telnet SUSP
+ * ^\: Do a ^u then send a telnet ABORT
+ * ^r: echo "^R\n" and redraw line
+ * ^v: quote next char
+ * ^d: if at BOL, end of file and close connection,
+ * else send line and reset to BOL
+ * ^m: send line-plus-\r\n and reset to BOL
+ */
+ case KCTRL('H'):
+ case KCTRL('?'): /* backspace/delete */
+ if (ldisc->buflen > 0) {
+ do {
+ if (ECHOING)
+ bsb(ldisc, plen(ldisc, ldisc->buf[ldisc->buflen - 1]));
+ ldisc->buflen--;
+ } while (!char_start(ldisc, ldisc->buf[ldisc->buflen]));
+ }
+ break;
+ case CTRL('W'): /* delete word */
+ while (ldisc->buflen > 0) {
+ if (ECHOING)
+ bsb(ldisc, plen(ldisc, ldisc->buf[ldisc->buflen - 1]));
+ ldisc->buflen--;
+ if (ldisc->buflen > 0 &&
+ isspace((unsigned char)ldisc->buf[ldisc->buflen-1]) &&
+ !isspace((unsigned char)ldisc->buf[ldisc->buflen]))
+ break;
+ }
+ break;
+ case CTRL('U'): /* delete line */
+ case CTRL('C'): /* Send IP */
+ case CTRL('\\'): /* Quit */
+ case CTRL('Z'): /* Suspend */
+ while (ldisc->buflen > 0) {
+ if (ECHOING)
+ bsb(ldisc, plen(ldisc, ldisc->buf[ldisc->buflen - 1]));
+ ldisc->buflen--;
+ }
+ ldisc->back->special(ldisc->backhandle, TS_EL);
+ /*
+ * We don't send IP, SUSP or ABORT if the user has
+ * configured telnet specials off! This breaks
+ * talkers otherwise.
+ */
+ if (!ldisc->cfg->telnet_keyboard)
+ goto default_case;
+ if (c == CTRL('C'))
+ ldisc->back->special(ldisc->backhandle, TS_IP);
+ if (c == CTRL('Z'))
+ ldisc->back->special(ldisc->backhandle, TS_SUSP);
+ if (c == CTRL('\\'))
+ ldisc->back->special(ldisc->backhandle, TS_ABORT);
+ break;
+ case CTRL('R'): /* redraw line */
+ if (ECHOING) {
+ int i;
+ c_write(ldisc, "^R\r\n", 4);
+ for (i = 0; i < ldisc->buflen; i++)
+ pwrite(ldisc, ldisc->buf[i]);
+ }
+ break;
+ case CTRL('V'): /* quote next char */
+ ldisc->quotenext = TRUE;
+ break;
+ case CTRL('D'): /* logout or send */
+ if (ldisc->buflen == 0) {
+ ldisc->back->special(ldisc->backhandle, TS_EOF);
+ } else {
+ ldisc->back->send(ldisc->backhandle, ldisc->buf, ldisc->buflen);
+ ldisc->buflen = 0;
+ }
+ break;
+ /*
+ * This particularly hideous bit of code from RDB
+ * allows ordinary ^M^J to do the same thing as
+ * magic-^M when in Raw protocol. The line `case
+ * KCTRL('M'):' is _inside_ the if block. Thus:
+ *
+ * - receiving regular ^M goes straight to the
+ * default clause and inserts as a literal ^M.
+ * - receiving regular ^J _not_ directly after a
+ * literal ^M (or not in Raw protocol) fails the
+ * if condition, leaps to the bottom of the if,
+ * and falls through into the default clause
+ * again.
+ * - receiving regular ^J just after a literal ^M
+ * in Raw protocol passes the if condition,
+ * deletes the literal ^M, and falls through
+ * into the magic-^M code
+ * - receiving a magic-^M empties the line buffer,
+ * signals end-of-line in one of the various
+ * entertaining ways, and _doesn't_ fall out of
+ * the bottom of the if and through to the
+ * default clause because of the break.
+ */
+ case CTRL('J'):
+ if (ldisc->cfg->protocol == PROT_RAW &&
+ ldisc->buflen > 0 && ldisc->buf[ldisc->buflen - 1] == '\r') {
+ if (ECHOING)
+ bsb(ldisc, plen(ldisc, ldisc->buf[ldisc->buflen - 1]));
+ ldisc->buflen--;
+ /* FALLTHROUGH */
+ case KCTRL('M'): /* send with newline */
+ if (ldisc->buflen > 0)
+ ldisc->back->send(ldisc->backhandle, ldisc->buf, ldisc->buflen);
+ if (ldisc->cfg->protocol == PROT_RAW)
+ ldisc->back->send(ldisc->backhandle, "\r\n", 2);
+ else if (ldisc->cfg->protocol == PROT_TELNET && ldisc->cfg->telnet_newline)
+ ldisc->back->special(ldisc->backhandle, TS_EOL);
+ else
+ ldisc->back->send(ldisc->backhandle, "\r", 1);
+ if (ECHOING)
+ c_write(ldisc, "\r\n", 2);
+ ldisc->buflen = 0;
+ break;
+ }
+ /* FALLTHROUGH */
+ default: /* get to this label from ^V handler */
+ default_case:
+ if (ldisc->buflen >= ldisc->bufsiz) {
+ ldisc->bufsiz = ldisc->buflen + 256;
+ ldisc->buf = sresize(ldisc->buf, ldisc->bufsiz, char);
+ }
+ ldisc->buf[ldisc->buflen++] = c;
+ if (ECHOING)
+ pwrite(ldisc, (unsigned char) c);
+ ldisc->quotenext = FALSE;
+ break;
+ }
+ }
+ } else {
+ if (ldisc->buflen != 0) {
+ ldisc->back->send(ldisc->backhandle, ldisc->buf, ldisc->buflen);
+ while (ldisc->buflen > 0) {
+ bsb(ldisc, plen(ldisc, ldisc->buf[ldisc->buflen - 1]));
+ ldisc->buflen--;
+ }
+ }
+ if (len > 0) {
+ if (ECHOING)
+ c_write(ldisc, buf, len);
+ if (keyflag && ldisc->cfg->protocol == PROT_TELNET && len == 1) {
+ switch (buf[0]) {
+ case CTRL('M'):
+ if (ldisc->cfg->protocol == PROT_TELNET && ldisc->cfg->telnet_newline)
+ ldisc->back->special(ldisc->backhandle, TS_EOL);
+ else
+ ldisc->back->send(ldisc->backhandle, "\r", 1);
+ break;
+ case CTRL('?'):
+ case CTRL('H'):
+ if (ldisc->cfg->telnet_keyboard) {
+ ldisc->back->special(ldisc->backhandle, TS_EC);
+ break;
+ }
+ case CTRL('C'):
+ if (ldisc->cfg->telnet_keyboard) {
+ ldisc->back->special(ldisc->backhandle, TS_IP);
+ break;
+ }
+ case CTRL('Z'):
+ if (ldisc->cfg->telnet_keyboard) {
+ ldisc->back->special(ldisc->backhandle, TS_SUSP);
+ break;
+ }
+
+ default:
+ ldisc->back->send(ldisc->backhandle, buf, len);
+ break;
+ }
+ } else
+ ldisc->back->send(ldisc->backhandle, buf, len);
+ }
+ }
+}
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