Add timeout feature to expect()

README.md

@@ -222,11 +222,13 @@ Tio suppots Lua scripting to easily automate interaction with the tty device.
 In addition to the Lua API tio makes the following functions available:
 
 ```
-  expect(string)
+  expect(string, timeout)
-        Expect string - waits for string to match before continueing.
+        Expect string - waits for string to match or timeout before continueing.
 
         Supports regular expressions. Special characters must be escaped with '\\'.
 
+        Timeout is in milliseconds, defaults to 0 meaning it will wait forever.
+
   send(string)
         Send string.
 

man/tio.1.in

@@ -379,8 +379,10 @@ In addition to the Lua API tio makes the following functions available:
 
 .TP 6n
 
-.IP "\fBexpect(string)"
+.IP "\fBexpect(string, timeout)"
-Expect string - waits for string to match before continueing. Supports regular expressions. Special characters must be escaped with '\\\\'.
+Expect string - waits for string to match or timeout before continueing.
+Supports regular expressions. Special characters must be escaped with '\\\\'.
+Timeout is in milliseconds, defaults to 0 meaning it will wait forever.
 .IP "\fBsend(string)"
 Send string.
 .IP "\fBmodem_send(file, protocol)"

src/misc.c

@@ -28,6 +28,7 @@
 #include <sys/stat.h>
 #include <time.h>
 #include <errno.h>
+#include <sys/poll.h>
 #include "error.h"
 #include "print.h"
 #include "options.h"
@@ -112,3 +113,31 @@ bool regex_match(const char *string, const char *pattern)
     // Match
     return true;
 }
+
+int read_poll(int fd, void *data, size_t len, int timeout)
+{
+    struct pollfd fds;
+    int ret = 0;
+
+    fds.events = POLLIN;
+    fds.fd = fd;
+
+    /* Wait data available */
+    ret = poll(&fds, 1, timeout);
+    if (ret < 0)
+    {
+        tio_error_print("%s", strerror(errno));
+        return ret;
+    }
+    else if (ret > 0)
+    {
+        if (fds.revents & POLLIN)
+        {
+            // Read ready data
+            return read(fd, data, len);
+        }
+    }
+
+    /* Timeout */
+    return ret;
+}

src/misc.h

@@ -22,6 +22,7 @@
 #pragma once
 
 #include <stdbool.h>
+#include <stdio.h>
 
 #define UNUSED(expr) do { (void)(expr); } while (0)
 
@@ -33,3 +34,4 @@ void alert_connect(void);
 void alert_disconnect(void);
 bool fs_dir_exists(const char *path);
 bool regex_match(const char *string, const char *pattern);
+int read_poll(int fd, void *data, size_t len, int timeout);

src/script.c

@@ -256,20 +256,27 @@ bool match_regex(regex_t *regex)
     return false;
 }
 
-// lua: expect(string)
+// lua: expect(string, timeout)
 static int expect(lua_State *L)
 {
     const char *string = lua_tostring(L, 1);
+    long timeout = lua_tointeger(L, 2);
     regex_t regex;
     int ret = 0;
     char c;
 
-    if (string == NULL)
+    if ((string == NULL) || (timeout < 0))
     {
         ret = -1;
         goto error;
     }
 
+    if (timeout == 0)
+    {
+        // Let poll() wait forever
+        timeout = -1;
+    }
+
     // Compile the regular expression
     ret = regcomp(&regex, string, REG_EXTENDED);
     if (ret)
@@ -282,7 +289,7 @@ static int expect(lua_State *L)
     // Main loop to read and match
     while (true)
     {
-        ssize_t bytes_read = read(serial_fd, &c, 1);
+        ssize_t bytes_read = read_poll(serial_fd, &c, 1, timeout);
         if (bytes_read > 0)
         {
             putchar(c);
@@ -293,6 +300,11 @@ static int expect(lua_State *L)
                 break;
             }
         }
+        else
+        {
+            // Timeout or error
+            break;
+        }
     }
 
     // Cleanup

src/xymodem.c

@@ -65,27 +65,6 @@ static uint16_t crc16(const uint8_t *data, uint16_t size)
     return crc;
 }
 
-static int serial_poll(int sio, void *data, size_t len, int timeout)
-{
-    struct pollfd fds[1];
-    fds[0].fd = sio;
-    fds[0].events = POLLIN ;
-    int ret = 0;
-
-    /* Wait data available */
-    ret = poll(fds, 1, timeout);
-    if (ret < 0) {
-        return ret;
-    }
-    else if (ret > 0) {
-        if(fds[0].revents & POLLIN) {
-            return read(sio, data, len);
-        }
-    }
-    /* Timeout */
-    return ret;
-}
-
 static int xmodem_1k(int sio, const void *data, size_t len, int seq)
 {
     struct xpacket_1k  packet;
@@ -99,7 +78,7 @@ static int xmodem_1k(int sio, const void *data, size_t len, int seq)
     while(1) {
         if (key_hit)
             return -1;
-        rc = serial_poll(sio, &resp, 1, 50);
+        rc = read_poll(sio, &resp, 1, 50);
         if (rc == 0) {
             if (resp == 'C') break;
             if (resp == CAN) return ERR;
@@ -156,7 +135,7 @@ static int xmodem_1k(int sio, const void *data, size_t len, int seq)
         for(int n=0; n < 20; n++) {
             if (key_hit)
                 return ERR;
-            rc = serial_poll(sio, &resp, 1, 50);
+            rc = read_poll(sio, &resp, 1, 50);
             if (rc < 0) {
                 tio_error_print("Read ack/nak from serial failed");
                 return ERR;
@@ -193,7 +172,7 @@ static int xmodem_1k(int sio, const void *data, size_t len, int seq)
         }
         write(STDOUT_FILENO, "|", 1);
         /* 1s timeout */
-        rc = serial_poll(sio, &resp, 1, 1000);
+        rc = read_poll(sio, &resp, 1, 1000);
         if (rc < 0) {
             tio_error_print("Read from serial failed");
             return ERR;
@@ -221,7 +200,7 @@ static int xmodem(int sio, const void *data, size_t len)
     while(1) {
         if (key_hit)
             return -1;
-        rc = serial_poll(sio, &resp, 1, 50);
+        rc = read_poll(sio, &resp, 1, 50);
         if (rc == 0) {
             if (resp == 'C') break;
             if (resp == CAN) return ERR;
@@ -275,7 +254,7 @@ static int xmodem(int sio, const void *data, size_t len)
         for(int n=0; n < 20; n++) {
             if (key_hit)
                 return ERR;
-            rc = serial_poll(sio, &resp, 1, 50);
+            rc = read_poll(sio, &resp, 1, 50);
             if (rc < 0) {
                 tio_error_print("Read ack/nak from serial failed");
                 return ERR;
@@ -312,7 +291,7 @@ static int xmodem(int sio, const void *data, size_t len)
         }
         write(STDOUT_FILENO, "|", 1);
         /* 1s timeout */
-        rc = serial_poll(sio, &resp, 1, 1000);
+        rc = read_poll(sio, &resp, 1, 1000);
         if (rc < 0) {
             tio_error_print("Read from serial failed");
             return ERR;