add a lo-fi mode

Fixes #113

NEWS

@@ -1,6 +1,11 @@
 
 lnav v0.7.2:
      * Added a log format for vdsm.
+     * Added a "lo-fi" mode (L hotkey) that dumps the displayed log lines
+       to the terminal without any decorations.  The write-to, write-json-to,
+       and write-csv-to commands will also write their output to the terminal
+       when passed '-' as the file name.  This mode can be useful for copying
+       plain text lines to the clipboard.
 
 lnav v0.7.1:
      Features:

docs/source/commands.rst

@@ -59,7 +59,8 @@ Output
 * append-to <file> - Append any bookmarked lines in the current view to the
   given file.
 * write-to <file> - Overwrite the given file with any bookmarked lines in
-  the current view.
+  the current view.  Use '-' to write the lines to the terminal.
 * write-csv-to <file> - Write SQL query results to the given file in CSV format.
+  Use '-' to write the lines to the terminal.
 * write-json-to <file> - Write SQL query results to the given file in JSON
-  format.
+  format.  Use '-' to write the lines to the terminal.

docs/source/hotkeys.rst

@@ -191,6 +191,9 @@ Display
      - Toggle the display of the log parser results
    * - |ks| Tab |ke|
      - Cycle through colums to graph in the SQL result view
+   * - |ks| L |ke|
+     - Switch to lo-fi mode.  The displayed log lines will be dumped to the
+       terminal without any decorations so they can be copied easily.
 
 Query
 -----

src/help.txt

@@ -164,6 +164,12 @@ through the file.
   t                 Switch to/from the text file view.  The text file view is
                     for any files that are not recognized as log files.
 
+  L                 (Lo-fi mode) Exit screen-mode and write the
+                    displayed log lines in plain text to the terminal
+                    until a key is pressed.  Useful for copying long lines
+                    from the terminal without picking up any of the extra
+                    decorations.
+
   o/O               Move forward/backward 60 minutes from the current
                     position in the log file.
 
@@ -417,19 +423,22 @@ COMMANDS
 
   append-to <file>  Append any marked lines to the given file.
 
-  write-to <file>   Write any marked lines to the given file.
+  write-to <file>   Write any marked lines to the given file.  Use '-' to
+                    write the lines to the terminal.
 
   write-csv-to <file>
                     Write the results of a SQL query to a CSV-formatted file.
                     When running in non-interactive mode, a dash can be used
-                    to write to standard out.
+                    to write to standard out.  Use '-' to write the data to
+                    the terminal.
 
   write-json-to <file>
                     Write the results of a SQL query to a JSON-formatted file.
                     The contents of the file will be an array of objects with
                     each column in the query being a field in the objects.
                     When running in non-interactive mode, a dash can be used
-                    to write to standard out.
+                    to write to standard out.  Use '-' to write the data to
+                    the terminal.
 
   session <cmd>     Add the given command to the session file
                     (~/.lnav/session).  Any commands listed in the session file

src/lnav.cc

@@ -1645,6 +1645,36 @@ static void handle_paging_key(int ch)
         }
         break;
 
+    case 'L': {
+        vis_line_t top = tc->get_top();
+        vis_line_t bottom = tc->get_bottom();
+        char line_break[80];
+
+        nodelay(lnav_data.ld_window, 0);
+        endwin();
+        {
+            guard_termios tguard(STDOUT_FILENO);
+            struct termios new_termios = *tguard.get_termios();
+            new_termios.c_oflag |= ONLCR | OPOST | OXTABS;
+            tcsetattr(STDOUT_FILENO, TCSANOW, &new_termios);
+            snprintf(line_break, sizeof(line_break),
+                    "\n---------------- Lines %'d-%'d ----------------\n\n",
+                    (int) top, (int) bottom);
+            write(STDOUT_FILENO, line_break, strlen(line_break));
+            for (; top <= bottom; ++top) {
+                attr_line_t al;
+                tc->listview_value_for_row(*tc, top, al);
+                write(STDOUT_FILENO, al.get_string().c_str(), al.length());
+                write(STDOUT_FILENO, "\n", 1);
+            }
+        }
+        cbreak();
+        getch();
+        refresh();
+        nodelay(lnav_data.ld_window, 1);
+        break;
+    }
+
     case 'M':
         if (lnav_data.ld_last_user_mark.find(tc) ==
             lnav_data.ld_last_user_mark.end()) {

src/lnav_commands.cc

@@ -315,6 +315,7 @@ static string com_save_to(string cmdline, vector<string> &args)
     FILE *      outfile = NULL;
     const char *mode    = "";
     string fn, retval;
+    bool to_term = false;
 
     if (args.size() == 0) {
         args.push_back("filename");
@@ -322,7 +323,7 @@ static string com_save_to(string cmdline, vector<string> &args)
     }
 
     if (args.size() < 2) {
-        return "error: expecting file name";
+        return "error: expecting file name or '-' to write to the terminal";
     }
 
     fn = trim(cmdline.substr(cmdline.find(args[1], args[0].size())));
@@ -364,12 +365,25 @@ static string com_save_to(string cmdline, vector<string> &args)
     }
 
     if (strcmp(wordmem->we_wordv[0], "-") == 0) {
-        if (!(lnav_data.ld_flags & LNF_HEADLESS)) {
-            return "error: writing to stdout is only available in headless mode";
-        }
         outfile = stdout;
+        if (lnav_data.ld_flags & LNF_HEADLESS) {
             lnav_data.ld_stdout_used = true;
         }
+        else {
+            nodelay(lnav_data.ld_window, 0);
+            endwin();
+            struct termios curr_termios;
+            tcgetattr(1, &curr_termios);
+            curr_termios.c_oflag |= ONLCR|OPOST|OXTABS;
+            tcsetattr(1, TCSANOW, &curr_termios);
+            setvbuf(stdout, NULL, _IONBF, 0);
+            to_term = true;
+            fprintf(outfile,
+                    "\n---------------- %s output, press any key to exit "
+                            "----------------\n\n",
+                    args[0].c_str());
+        }
+    }
     else if ((outfile = fopen(wordmem->we_wordv[0], mode)) == NULL) {
         return "error: unable to open file -- " + string(wordmem->we_wordv[0]);
     }
@@ -437,6 +451,12 @@ static string com_save_to(string cmdline, vector<string> &args)
         }
     }
 
+    if (to_term) {
+        cbreak();
+        getch();
+        refresh();
+        nodelay(lnav_data.ld_window, 1);
+    }
     if (outfile != stdout) {
         fclose(outfile);
     }

test/Makefile.am

@@ -223,6 +223,7 @@ dist_noinst_DATA = \
 	logfile_tcf.0 \
 	logfile_tcf.1 \
 	logfile_tcsh_history.0 \
+	logfile_vdsm.0 \
 	logfile_with_a_really_long_name_to_test_a_bug_with_long_names.0 \
 	mvwattrline_output.0 \
 	simple-db.sql \

test/Makefile.in

@@ -805,6 +805,7 @@ dist_noinst_DATA = \
 	logfile_tcf.0 \
 	logfile_tcf.1 \
 	logfile_tcsh_history.0 \
+	logfile_vdsm.0 \
 	logfile_with_a_really_long_name_to_test_a_bug_with_long_names.0 \
 	mvwattrline_output.0 \
 	simple-db.sql \