Reimplemented window size handling

this fixes #30
this fixes #17
this fixes #33

 * shellex main executable creates a temporary file
 * perl module writes maximum size to that file
 * preload library reads from there and deletes file

LICENSE

@@ -1,4 +1,4 @@
-Copyright © 2013 Axel Wagner
+Copyright © 2016 Axel Wagner and contributors
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without

conf/10-autoexec

@@ -28,7 +28,8 @@ function shellex_preexec () {
 
     # We write the expanded form of the command to the tempfile, because the
     # executet shell will not have our aliases or functions available
-    echo "rm $file\n$3" > $file
+    echo "rm $file" > $file
+    echo "$3" >> $file
 
     # prevent writing meaningless "zsh $file > /dev/null ...." to history
     unset HISTFILE

doc/autoresize.txt

@@ -12,15 +12,15 @@ shellex, because when is starting it's output, there is not enough space, for
 the tabcompletion, so even if we immediately resize the terminalwindow, it will
 be too late and the shell-output is screwed up.
 
-We rectify this, by injecting a custom ioctl-function into urxvt via
-LD_PRELOAD, which rewrites all TIOCSWINSZ-requests to have a constant size,
-thus faking to the shell that there is more space available, then there
-actually is. The actual number of rows is calculated on start of the urxvt and
-put into an environment-variable.
+We rectify this, by injecting a custom ioctl-function into zsh via LD_PRELOAD,
+which rewrites all TIOCGWINSZ-requests to have a constant size. This fakes to
+the shell that there is more space available, then there actually is.  The
+actual number of rows is calculated on start of the urxvt and put into a
+temporary file. The size is chosen a bit smaller than the screen, such that if
+zsh needs even more space for the tabcompletion than fits on the screen, the
+zsh handeling to deal with less space gets active. The filename is generated
+with mktemp before either zsh or urxvt start. The file gets unlinked by
+preload/main.c once a successful read happened.
 
-
-
-With the current state, the window of shellex is able to grow automatically
-exactly one time. This is, because zsh is spamming the output with '\n', if we
-grow it always and we have yet to figure out why and how to stop that.
-Shrinking (i.e. when the tab-completion vanishes again) is not implemented yet.
+Shrinking after tab completions mostly works fine: Depending on the
+tabcompletion settings, shrinking breaks once one hit the maximum size limit.

preload/main.c

@@ -6,6 +6,8 @@
 #define _GNU_SOURCE
 #include <dlfcn.h>
 #include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
 
 /* We can not take this from <sys/ioctl.h>, because it would define the
  * ioctl-function itself
@@ -22,28 +24,46 @@ int ioctl (int d, int request, char *argp) {
     if (orig_ioctl == NULL) {
         orig_ioctl = dlsym(RTLD_NEXT, "ioctl");
     }
+
+    /* We only care for TIOCGWINSZ ioctls */
+    if (request != 0x5413) {
+        return orig_ioctl(d, request, argp);
+    }
+
     static int max_rows = -1;
+
+    /* ioctl gets called once before the perl module had the time to determine
+     * the right size! Leave max_rows negative to indicat that it still needs to
+     * be read from the SHELLEX_SIZE_FILE */
+
     if (max_rows < 0 ) {
-        char *str = getenv("SHELLEX_MAX_ROWS");
-        if (str != NULL) {
-            max_rows = atoi(str);
+
+        char *fname = getenv("SHELLEX_SIZE_FILE");
+        if (fname != NULL && fname[0] != '\0') {
+            FILE *stream = fopen(fname,"r");
+            char str[5] = "-500";
+            if (stream != NULL) {
+                char *ret = fgets(str,5,stream);
+                fclose(stream);
+                if (ret != NULL) {
+                    /* this may be -500 */
+                    max_rows = atoi(str);
+                    if (max_rows > 0 ) {
+                        unlink(fname);
+                    }
+                }
+            }
         }
     }
 
-    // We only care for TIOCSWINSZ ioctls
-    if (request != 0x5414) {
-        return orig_ioctl(d, request, argp);
-    }
 
-    struct winsize ws = *((struct winsize *)argp);
-    int fheight = ws.ws_ypixel / ws.ws_row;
-    if (max_rows < 0) {
-        ws.ws_row = 80;
-        ws.ws_ypixel += 80 * fheight;
-    } else {
-        ws.ws_row = max_rows;
-        ws.ws_ypixel += max_rows * fheight;
-    }
+    int retval = orig_ioctl(d, request, (char *)argp);
+    struct winsize *ws = (struct winsize *)argp;
+
+    /* max_rows is still negative at first invocation */
+    int fheight = ws->ws_ypixel / ws->ws_row;
+    ws->ws_row = (max_rows > 0) ? max_rows : 25;
+    ws->ws_ypixel = ws->ws_row * fheight;
 
-    return orig_ioctl(d, request, (char *)&ws);
+    return retval;
 }

shellex.in

@@ -4,6 +4,6 @@
 #   See shellex(1) for information on invocation.
 # © 2013 Axel Wagner and contributors (see also: LICENSE)
 
-
-export LD_PRELOAD="@PREFIX@@LIBDIR@/shellex/shellex_preload.so"
-exec urxvt -perl-lib @PREFIX@@LIBDIR@/shellex/urxvt -pe shellex -override-redirect -name shellex $* -e env -u LD_PRELOAD zsh -f
+SHELLEX_PRELOAD="@PREFIX@@LIBDIR@/shellex/shellex_preload.so"
+export SHELLEX_SIZE_FILE=$(mktemp -t shellex-size-XXXXXXXX)
+exec urxvt -perl-lib @PREFIX@@LIBDIR@/shellex/urxvt -pe shellex -override-redirect -name shellex $* -e env LD_PRELOAD=$SHELLEX_PRELOAD  zsh -f

urxvt/shellex.in

@@ -203,7 +203,17 @@ sub on_start {
 
     # This environment variable is used by the LD_PRELOAD ioctl-override to
     # determine the values to send to the shell
-    $ENV{SHELLEX_MAX_ROWS} = int($self->{h} / $self->fheight);
+    # TODO revisit communication protocol (from file to pipe?)
+    # TODO check if user defined their own SHELLEX_MAX_ROWS, which should be used like
+    #$ENV{SHELLEX_MAX_ROWS} = $sane_max_rows < $ENV{SHELLEX_MAX_ROWS} ? $sane_max_rows : $ENV{SHELLEX_MAX_ROWS} ;
+    my $sane_max_rows = int($self->{h} / $self->fheight) - 10;
+
+    $ENV{SHELLEX_MAX_ROWS} = $sane_max_rows;
+    my $filename = $ENV{SHELLEX_SIZE_FILE};
+    open(my $fh, '>', $filename);
+    print $fh "$ENV{SHELLEX_MAX_ROWS}\n";
+    close $fh;
+    print "writing max rows file done\n";
 
     $self->{border} = $self->x_resource('internalBorder');
 
@@ -223,6 +233,8 @@ sub on_start {
 
     my $cfg = gen_conf();
 
+    print "loading config\n";
+    $self->tt_write($self->locale_encode("unset LD_PRELOAD\n"));
     $self->tt_write($self->locale_encode(". $cfg\n"));
     ();
 }
@@ -243,6 +255,7 @@ sub on_line_update {
         }
     }
     $nrow = $nrow > 0 ? $nrow : 1;
+    $nrow = $nrow > $ENV{SHELLEX_MAX_ROWS} ? $ENV{SHELLEX_MAX_ROWS} : $nrow;
     print "resizing to $nrow\n";
 
     # If the window is supposed to be at the bottom, we have to move the
@@ -315,6 +328,8 @@ sub on_add_lines {
     print "add_lines(string = \"$str\")\n";
 
     my $nrow = $self->predict_term_size($string);
+    $nrow = $nrow > 0 ? $nrow : 1;
+    $nrow = $nrow > $ENV{SHELLEX_MAX_ROWS} ? $ENV{SHELLEX_MAX_ROWS} : $nrow;
     print "resizing to $nrow\n";
 
     # If the window is supposed to be at the bottom, we have to move the