From 299884750e87e05c9d804e7f0fbcb08e02b37a8d Mon Sep 17 00:00:00 2001
From: "H. Peter Anvin" <hpa@zytor.com>
Date: Sat, 16 Sep 2006 14:35:58 -0700
Subject: [PATCH] Proper handling of different screen sizes (we're 78x29 in
 graphics mode...)

---
 com32/include/unistd.h        |  1 +
 com32/lib/Makefile            |  2 +-
 com32/lib/sys/ansicon_write.c |  7 ++++---
 com32/lib/sys/file.h          |  5 +++++
 com32/lib/sys/isatty.c        |  1 +
 com32/lib/sys/opendev.c       |  3 +--
 com32/lib/sys/vesacon_write.c |  9 ++++++++-
 com32/modules/menumain.c      | 15 +++++++++++++++
 8 files changed, 36 insertions(+), 7 deletions(-)

diff --git a/com32/include/unistd.h b/com32/include/unistd.h
index 84120d3..d0b8309 100644
--- a/com32/include/unistd.h
+++ b/com32/include/unistd.h
@@ -20,6 +20,7 @@ __extern ssize_t write(int, const void *, size_t);
 
 __extern int isatty(int);
 
+__extern int getscreensize(int, int *, int *);
 
 /* Standard file descriptor numbers. */
 #define STDIN_FILENO	0
diff --git a/com32/lib/Makefile b/com32/lib/Makefile
index e3cef23..a6355c9 100644
--- a/com32/lib/Makefile
+++ b/com32/lib/Makefile
@@ -28,7 +28,7 @@ LIBOBJS = \
 	sys/fileinfo.o sys/opendev.o sys/read.o sys/write.o sys/ftell.o \
 	sys/close.o sys/open.o sys/fileread.o sys/fileclose.o		\
 	sys/isatty.o sys/fstat.o sys/openconsole.o sys/line_input.o	\
-	sys/colortable.o						\
+	sys/colortable.o sys/screensize.o				\
 	\
 	sys/stdcon_read.o sys/stdcon_write.o sys/rawcon_read.o		\
 	sys/rawcon_write.o sys/err_read.o sys/err_write.o		\
diff --git a/com32/lib/sys/ansicon_write.c b/com32/lib/sys/ansicon_write.c
index 1fab2ac..c500adb 100644
--- a/com32/lib/sys/ansicon_write.c
+++ b/com32/lib/sys/ansicon_write.c
@@ -1,6 +1,6 @@
 /* ----------------------------------------------------------------------- *
  *
- *   Copyright 2004 H. Peter Anvin - All Rights Reserved
+ *   Copyright 2004-2006 H. Peter Anvin - All Rights Reserved
  *
  *   Permission is hereby granted, free of charge, to any person
  *   obtaining a copy of this software and associated documentation
@@ -80,8 +80,6 @@ int __ansicon_open(struct file_info *fp)
   static com32sys_t ireg;	/* Auto-initalized to all zero */
   com32sys_t oreg;
 
-  (void)fp;
-
   if (!ansicon_counter) {
     /* Are we disabled? */
     ireg.eax.w[0] = 0x000b;
@@ -109,6 +107,9 @@ int __ansicon_open(struct file_info *fp)
     }
   }
 
+  fp->o.rows = ti.rows;
+  fp->o.cols = ti.cols;
+
   ansicon_counter++;
   return 0;
 }
diff --git a/com32/lib/sys/file.h b/com32/lib/sys/file.h
index 3b73848..6138608 100644
--- a/com32/lib/sys/file.h
+++ b/com32/lib/sys/file.h
@@ -91,6 +91,11 @@ struct file_info {
     char *datap;		/* Current data pointer */
     char buf[MAXBLOCK];
   } i;
+
+  /* Output file data */
+  struct {
+    int rows, cols;		/* Rows and columns */
+  } o;
 };
 
 extern struct file_info __file_info[NFILES];
diff --git a/com32/lib/sys/isatty.c b/com32/lib/sys/isatty.c
index c0a14db..837a90a 100644
--- a/com32/lib/sys/isatty.c
+++ b/com32/lib/sys/isatty.c
@@ -48,5 +48,6 @@ int isatty(int fd)
     return -1;
   }
 
+  /* __DEV_TTY == 1 */
   return (fp->iop->flags & __DEV_TTY);
 }
diff --git a/com32/lib/sys/opendev.c b/com32/lib/sys/opendev.c
index 1bcc101..a61da0c 100644
--- a/com32/lib/sys/opendev.c
+++ b/com32/lib/sys/opendev.c
@@ -61,10 +61,9 @@ int opendev(const struct input_dev *idev,
     return -1;
   }
 
+  /* The file structure is already zeroed */
   fp->iop         = &dev_error_r;
   fp->oop         = &dev_error_w;
-  fp->i.offset    = 0;
-  fp->i.nbytes    = 0;
   fp->i.datap     = fp->i.buf;
 
   if (idev) {
diff --git a/com32/lib/sys/vesacon_write.c b/com32/lib/sys/vesacon_write.c
index da94006..7f1570b 100644
--- a/com32/lib/sys/vesacon_write.c
+++ b/com32/lib/sys/vesacon_write.c
@@ -85,15 +85,22 @@ int __vesacon_open(struct file_info *fp)
       ti.disabled = 1;
     } else {
       /* Switch mode */
-      if (__vesacon_init())
+      if (__vesacon_init()) {
+	vesacon_counter = -1;
 	return EAGAIN;
+      }
 
       /* Initial state */
       __ansi_init(&ti);
       ti.rows = __vesacon_text_rows;
     }
+  } else if (vesacon_counter == -1) {
+    return EAGAIN;
   }
 
+  fp->o.rows = ti.rows;
+  fp->o.cols = ti.cols;
+
   vesacon_counter++;
   return 0;
 }
diff --git a/com32/modules/menumain.c b/com32/modules/menumain.c
index 282618c..433f169 100644
--- a/com32/modules/menumain.c
+++ b/com32/modules/menumain.c
@@ -845,12 +845,27 @@ execute(const char *cmdline)
 int menu_main(int argc, char *argv[])
 {
   const char *cmdline;
+  int rows, cols;
+  int i;
 
   (void)argc;
 
   install_default_color_table();
+  if (getscreensize(1, &rows, &cols)) {
+    /* Unknown screen size? */
+    rows = 24;
+    cols = 80;
+  }
+
+  WIDTH = cols;
   parse_config(argv[1]);
 
+  /* If anyone has specified negative parameters, consider them
+     relative to the bottom row of the screen. */
+  for (i = 0; mparm[i].name; i++)
+    if (mparm[i].value < 0)
+      mparm[i].value = max(mparm[i].value+rows, 0);
+
   if (draw_background)
     draw_background(menu_background);
 
-- 
2.7.4