Added log feature

Added "--log <filename>" option which writes all activity to specified
file.

README

@@ -29,6 +29,7 @@
           -p, --parity even|odd|none  Parity (default: none)
           -o, --output-delay <ms>     Output delay (default: 0)
           -n, --no-autoconnect        Disable automatic connect
+          -l, --log <filename>        Log to file
           -v, --version               Display version
           -h, --help                  Display help
 

man/gotty.1

@@ -47,6 +47,10 @@ Set output delay [ms] - delay inserted between each transmitted character (defau
 
 Disable automatic connect.
 .TP
+.B \-l, \--log <filename>
+
+Log to file.
+.TP
 .B \-v, \--version
 
 Display program version.

src/bash-completion/gotty

@@ -17,6 +17,7 @@ _gotty()
           -p --parity \
           -o --output-delay \
           -n --no-autoconnect \
+          -l --log \
           -v --version \
           -h --help"
 
@@ -79,6 +80,10 @@ _gotty()
             COMPREPLY=( $(compgen -W "${opts}" -- ${cur}) )
             return 0
             ;;
+        -l | --log)
+            COMPREPLY=( $(compgen -W "${opts}" -- ${cur}) )
+            return 0
+            ;;
         -v | --version)
             COMPREPLY=( $(compgen -W "${opts}" -- ${cur}) )
             return 0

src/include/gotty/log.h

@@ -0,0 +1,30 @@
+/*
+ * Go TTY - The Really Simple Terminal Application
+ *
+ * Copyright (c) 2014-2016  Martin Lund
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#ifndef LOG_H
+#define LOG_H
+
+void log_open(char *filename);
+void log_write(char c);
+void log_close(void);
+void log_exit(void);
+
+#endif

src/include/gotty/options.h

@@ -31,9 +31,11 @@
 struct option_t
 {
     char tty_device[MAXPATHLEN];
+    bool log;
+    char log_filename[_POSIX_ARG_MAX];
     bool no_autoconnect;
-    struct termios tio;
     int output_delay;
+    struct termios tio;
 };
 
 extern struct option_t option;

src/log.c

@@ -0,0 +1,62 @@
+/*
+ * Go TTY - The Really Simple Terminal Application
+ *
+ * Copyright (c) 2014-2016  Martin Lund
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include "gotty/options.h"
+#include "gotty/print.h"
+
+static FILE *fp;
+static bool error = false;
+
+void log_open(char *filename)
+{
+    fp = fopen(filename, "w+");
+
+    if (fp == NULL)
+    {
+        error = true;
+        exit(EXIT_FAILURE);
+    }
+}
+
+void log_write(char c)
+{
+    if (fp != NULL)
+        fputc(c, fp);
+}
+
+void log_close(void)
+{
+    if (fp != NULL)
+        fclose(fp);
+}
+
+void log_exit(void)
+{
+    if (option.log)
+        log_close();
+
+    if (error)
+        printf("Error: Could not open log file %s (%s)\n", option.log_filename, strerror(errno));
+}

src/main.c

@@ -23,6 +23,7 @@
 #include <stdlib.h>
 #include "gotty/options.h"
 #include "gotty/tty.h"
+#include "gotty/log.h"
 
 int main(int argc, char *argv[])
 {
@@ -34,9 +35,16 @@ int main(int argc, char *argv[])
     /* Configure output terminal */
     configure_stdout();
 
+    /* Install log exit handler */
+    atexit(&log_exit);
+
     /* Restore output terminal on exit */
     atexit(&restore_stdout);
 
+    /* Create log file */
+    if (option.log)
+        log_open(option.log_filename);
+
     /* Connect to tty device */
     if (option.no_autoconnect)
         status = connect_tty();
@@ -50,5 +58,8 @@ int main(int argc, char *argv[])
         }
     }
 
+    /* Close log */
+    log_close();
+
     return status;
 }

src/options.c

@@ -27,14 +27,18 @@
 #include <errno.h>
 #include <getopt.h>
 #include <termios.h>
+#include <limits.h>
 #include "config.h"
 #include "gotty/options.h"
 #include "gotty/print.h"
 
 struct option_t option =
 {
-    "",       /* Device name */
-    false,    /* No autoconnect */
+    "",       // Device name
+    false,    // No log
+    "",       // Log filename
+    false,    // No autoconnect
+    0,        // No output delay
 };
 
 void print_options_help(char *argv[])
@@ -49,6 +53,7 @@ void print_options_help(char *argv[])
     printf("  -p, --parity odd|even|none  Parity (default: none)\n");
     printf("  -o, --output-delay <ms>     Output delay (default: 0)\n");
     printf("  -n, --no-autoconnect        Disable automatic connect\n");
+    printf("  -l, --log <filename>        Log to file\n");
     printf("  -v, --version               Display version\n");
     printf("  -h, --help                  Display help\n");
     printf("\n");
@@ -88,6 +93,7 @@ void parse_options(int argc, char *argv[])
             {"parity",         required_argument, 0, 'p'},
             {"output-delay",   required_argument, 0, 'o'},
             {"no-autoconnect", no_argument,       0, 'n'},
+            {"log",            required_argument, 0, 'l'},
             {"version",	       no_argument,       0, 'v'},
             {"help",           no_argument,       0, 'h'},
             {0,                0,                 0,  0 }
@@ -97,7 +103,7 @@ void parse_options(int argc, char *argv[])
         int option_index = 0;
 
         /* Parse argument using getopt_long */
-        c = getopt_long(argc, argv, "b:d:f:s:p:o:nvh", long_options, &option_index);
+        c = getopt_long(argc, argv, "b:d:f:s:p:o:nl:vh", long_options, &option_index);
 
         /* Detect the end of the options */
         if (c == -1)
@@ -306,6 +312,11 @@ void parse_options(int argc, char *argv[])
                 option.no_autoconnect = true;
                 break;
 
+            case 'l':
+                option.log = true;
+                strncpy(option.log_filename, optarg, _POSIX_ARG_MAX);
+                break;
+
             case 'v':
                 printf("Go TTY v%s\n", VERSION);
                 printf("Copyright (c) 2014-2016 Martin Lund\n");

src/tty.c

@@ -35,6 +35,7 @@
 #include "gotty/print.h"
 #include "gotty/options.h"
 #include "gotty/time.h"
+#include "gotty/log.h"
 
 static int connected = false;
 struct termios new_stdout, old_stdout, old_tio;
@@ -204,6 +205,11 @@ int connect_tty(void)
                 /* Print received tty character to stdout */
                 putchar(c_tty);
                 fflush(stdout);
+
+                /* Write to log */
+                if (option.log)
+                    log_write(c_tty);
+
                 if (c_tty != 0x7) // Small trick to avoid ctrl-g echo
                     tainted = true;
             } else
@@ -229,6 +235,10 @@ int connect_tty(void)
             /* Forward input to tty device */
             status = write(fd, &c_stdin[0], 1);
 
+            /* Write to log */
+            if (option.log)
+                log_write(c_stdin[0]);
+
             /* Insert output delay */
             if (option.output_delay)
                 usleep(option.output_delay * 1000);