aboutsummaryrefslogtreecommitdiff
path: root/lib/lib.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/lib.c')
-rw-r--r--lib/lib.c98
1 files changed, 98 insertions, 0 deletions
diff --git a/lib/lib.c b/lib/lib.c
index 1a60a7ff..ab773b5b 100644
--- a/lib/lib.c
+++ b/lib/lib.c
@@ -637,6 +637,40 @@ int terminal_size(unsigned *xx, unsigned *yy)
return x || y;
}
+// Reset terminal to known state, saving copy of old state if old != NULL.
+int set_terminal(int fd, int raw, struct termios *old)
+{
+ struct termios termio;
+
+ // Fetch local copy of old terminfo, and copy struct contents to *old if set
+ if (!tcgetattr(fd, &termio) && old) *old = termio;
+
+ // the following are the bits set for an xterm. Linux text mode TTYs by
+ // default add two additional bits that only matter for serial processing
+ // (turn serial line break into an interrupt, and XON/XOFF flow control)
+
+ // Any key unblocks output, swap CR and NL on input
+ termio.c_iflag = IXANY|ICRNL|INLCR;
+ if (toys.which->flags & TOYFLAG_LOCALE) termio.c_iflag |= IUTF8;
+
+ // Output appends CR to NL, does magic undocumented postprocessing
+ termio.c_oflag = ONLCR|OPOST;
+
+ // Leave serial port speed alone
+ // termio.c_cflag = C_READ|CS8|EXTB;
+
+ // Generate signals, input entire line at once, echo output
+ // erase, line kill, escape control characters with ^
+ // erase line char at a time
+ // "extended" behavior: ctrl-V quotes next char, ctrl-R reprints unread chars,
+ // ctrl-W erases word
+ termio.c_lflag = ISIG|ICANON|ECHO|ECHOE|ECHOK|ECHOCTL|ECHOKE|IEXTEN;
+
+ if (raw) cfmakeraw(&termio);
+
+ return tcsetattr(fd, TCSANOW, &termio);
+}
+
int yesno(char *prompt, int def)
{
char buf;
@@ -895,3 +929,67 @@ int qstrcmp(const void *a, const void *b)
{
return strcmp(*(char **)a, *(char **)b);
}
+
+int xpoll(struct pollfd *fds, int nfds, int timeout)
+{
+ int i;
+
+ for (;;) {
+ if (0>(i = poll(fds, nfds, timeout))) {
+ if (errno != EINTR && errno != ENOMEM) perror_exit("xpoll");
+ else if (timeout>0) timeout--;
+ } else return i;
+ }
+}
+
+// Scan stdin for a keypress, parsing known escape sequences
+// seq is array of char * strings, ends with NULL ptr
+// Returns: 0-255=literal, -1=EOF, -2=NONE, 256-...=index into seq
+// scratch space is necessary because last char of !seq could start new seq
+// Zero out first byte of scratch before first call to scan_key
+// block=0 allows fetching multiple characters before updating display
+int scan_key(char *scratch, char **seqs, int block)
+{
+ struct pollfd pfd;
+ int maybe, i, j;
+ char *test;
+
+ for (;;) {
+ pfd.fd = 0;
+ pfd.events = POLLIN;
+ pfd.revents = 0;
+
+ // check sequences
+ maybe = 0;
+ if (*scratch) {
+ for (i = maybe = 0; (test = seqs[i]); i++) {
+ for (j = 0; j<*scratch; j++) if (scratch[j+1] != test[j]) break;
+ if (j == *scratch) {
+ maybe = 1;
+ if (!test[j]) {
+ // We recognized current sequence: consume and return
+ *scratch = 0;
+ return 256+i;
+ }
+ }
+ }
+ // If current data can't be a known sequence, return next raw char
+ if (!maybe) break;
+ }
+
+ // Need more data to decide
+
+ // 30 miliseconds is about the gap between characters at 300 baud
+ if (maybe || !block) if (!xpoll(&pfd, 1, 30*maybe)) break;
+
+ if (1 != read(0, scratch+1+*scratch, 1)) return -1;
+ ++*scratch;
+ }
+
+ // Was not a sequence
+ if (!*scratch) return -2;
+ i = scratch[1];
+ if (--*scratch) memmove(scratch+1, scratch+2, *scratch);
+
+ return i;
+}