From 3b3ab4464c943a9da5e36e1375a86acbc264834c Mon Sep 17 00:00:00 2001
From: Elliott Hughes <enh@google.com>
Date: Wed, 25 Oct 2023 17:41:37 -0700
Subject: [PATCH] microcom: simple menu, new "paste file" functionality.

Rather than take up yet another key for the new functionality, I've moved
everything to a menu, similar to the one in telnet. It's not amazing,
but it's the least code I could get away with, and it's good enough for
now, and it leaves us in a better place if we need to add more stuff
(such as xmodem, say).

But this is enough to let me stop using minicom and get back to toybox
microcom for today!
---
 toys/net/microcom.c | 71 ++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 63 insertions(+), 8 deletions(-)

diff --git a/toys/net/microcom.c b/toys/net/microcom.c
index 963445c2..66799b94 100644
--- a/toys/net/microcom.c
+++ b/toys/net/microcom.c
@@ -13,7 +13,7 @@ config MICROCOM
     Simple serial console.
 
     -s	Set baud rate to SPEED (default 115200)
-    -X	Ignore ^@ (send break) and ^] (exit)
+    -X	Ignore ^] escape (default is ^] for menu)
 */
 
 #define FOR_microcom
@@ -33,6 +33,65 @@ static void restore_states(int i)
   tcsetattr(TT.fd, TCSAFLUSH, &TT.old_fd);
 }
 
+static void handle_esc(void)
+{
+  char input;
+
+  xputsn("\r\n"
+         "Commands are:\r\n"
+         " b  send Break\r\n"
+         " p  paste file\r\n"
+         " x  eXit microcom\r\n"
+         "\r\n"
+         "microcom> ");
+  if (read(0, &input, 1) <= 0 || input == CTRL('D') || input == 'x') {
+    xputs("Connection closed.\r");
+    xexit();
+  }
+  if (input == 'b') {
+    tcsendbreak(TT.fd, 0);
+  } else if (input == 'p') {
+    long long written = 0, size;
+    char* filename;
+    int len = 0, fd;
+
+    // TODO: share code with hexedit's prompt() and vi's ex mode.
+    // TODO: tab completion!
+    memset(toybuf, 0, sizeof(toybuf));
+    while (1) {
+      xprintf("\r\e[2K\e[1mFilename: \e[0m%s", toybuf);
+      if (read(0, &input, 1) <= 0 || input == CTRL('[')) {
+        return;
+      }
+      if (input == '\r') break;
+      if (input == 0x7f && len > 0) toybuf[--len] = 0;
+      else if (input == CTRL('U')) while (len > 0) toybuf[--len] = 0;
+      else if (input >= ' ' && input <= 0x7f && len < sizeof(toybuf))
+        toybuf[len++] = input;
+    }
+    toybuf[len] = 0;
+    if (!len) return;
+    filename = xstrdup(toybuf);
+    fd = xopen(filename, O_RDONLY);
+    size = fdlength(fd);
+    // The alternative would be to just feed this fd into the usual loop,
+    // so we're reading back these characters if they're being echoed, but
+    // for my specific use case of pasting into `base64 -d -i > foo`, this
+    // is a much more convenient UI.
+    while ((len = read(fd, toybuf, sizeof(toybuf))) > 0) {
+      written += len;
+      xprintf("\r\e[2KPasting '%s' %lld/%lld (%lld%%)...", filename, written,
+        size, written*100/size);
+      xwrite(TT.fd, toybuf, len);
+    }
+    free(filename);
+    close(fd);
+  } else {
+    xprintf("Ignoring unknown command.");
+  }
+  xprintf("\r\n");
+}
+
 void microcom_main(void)
 {
   struct termios tio;
@@ -58,6 +117,7 @@ void microcom_main(void)
   fds[1].fd = 0;
   fds[0].events = fds[1].events = POLLIN;
 
+  if (!FLAG(X)) xputs("Escape character is '^]'.\r");
   while (poll(fds, 2, -1) > 0) {
 
     // Read from connection, write to stdout.
@@ -69,13 +129,8 @@ void microcom_main(void)
     // Read from stdin, write to connection.
     if (fds[1].revents) {
       if (read(0, toybuf, 1) != 1) break;
-      if (!FLAG(X)) {
-        if (!*toybuf) {
-          tcsendbreak(TT.fd, 0);
-          continue;
-        } else if (*toybuf == (']'-'@')) break;
-      }
-      xwrite(TT.fd, toybuf, 1);
+      if (!FLAG(X) && *toybuf == CTRL(']')) handle_esc();
+      else xwrite(TT.fd, toybuf, 1);
     }
   }
 }
-- 
2.39.2