options.py: get the real tty width for word wrapping purposes.

Previously we just assumed it was 70 chars, which was safe enough, but not
as elegant as actually reading the real value and adjusting the word wrap of
the usage string accordingly.

Signed-off-by: Avery Pennarun <apenwarr@gmail.com>

diff --git a/lib/bup/helpers.py b/lib/bup/helpers.py
index 34067006f099b07695da943087cfc327d4702c2a..f911b046151123c8c31d85c6b41d9dae7dd97e7e 100644 (file)
--- a/lib/bup/helpers.py
+++ b/lib/bup/helpers.py
@@ -2,6 +2,11 @@
 import sys, os, pwd, subprocess, errno, socket, select, mmap, stat, re
 from bup import _version
 
+# This function should really be in helpers, not in bup.options.  But we
+# want options.py to be standalone so people can include it in other projects.
+from bup.options import _tty_width
+tty_width = _tty_width
+
 
 def atoi(s):
     """Convert the string 's' to an integer. Return 0 if s is not a number."""
@@ -368,7 +373,7 @@ def columnate(l, prefix):
         return ""
     l = l[:]
     clen = max(len(s) for s in l)
-    ncols = (78 - len(prefix)) / (clen + 2)
+    ncols = (tty_width() - len(prefix)) / (clen + 2)
     if ncols <= 1:
         ncols = 1
         clen = 0

diff --git a/lib/bup/options.py b/lib/bup/options.py
index 650e10af38a34f87dabd883f6e354fb7cba50e7a..5ff2a850a546007e9ff72e698518b8471a9946ee 100644 (file)
--- a/lib/bup/options.py
+++ b/lib/bup/options.py
@@ -1,10 +1,7 @@
 """Command-line options parser.
 With the help of an options spec string, easily parse command-line options.
 """
-import sys
-import textwrap
-import getopt
-import re
+import sys, os, textwrap, getopt, re, struct
 
 class OptDict:
     def __init__(self):
@@ -39,6 +36,13 @@ def _intify(v):
     return v
 
 
+def _atoi(v):
+    try:
+        return int(v or 0)
+    except ValueError:
+        return 0
+
+
 def _remove_negative_kv(k, v):
     if k.startswith('no-') or k.startswith('no_'):
         return k[3:], not v
@@ -48,6 +52,17 @@ def _remove_negative_k(k):
     return _remove_negative_kv(k, None)[0]
 
 
+def _tty_width():
+    s = struct.pack("HHHH", 0, 0, 0, 0)
+    try:
+        import fcntl, termios
+        s = fcntl.ioctl(sys.stderr.fileno(), termios.TIOCGWINSZ, s)
+    except (IOError, ImportError):
+        return _atoi(os.environ.get('WIDTH')) or 70
+    (ysize,xsize,ypix,xpix) = struct.unpack('HHHH', s)
+    return xsize
+
+
 class Options:
     """Option parser.
     When constructed, two strings are mandatory. The first one is the command
@@ -125,7 +140,7 @@ class Options:
                 if has_parm:
                     flags_nice += ' ...'
                 prefix = '    %-20s  ' % flags_nice
-                argtext = '\n'.join(textwrap.wrap(extra, width=70,
+                argtext = '\n'.join(textwrap.wrap(extra, width=_tty_width(),
                                                 initial_indent=prefix,
                                                 subsequent_indent=' '*28))
                 out.append(argtext + '\n')

diff --git a/main.py b/main.py
index 7a7e426ff8800ce5eba951beba9474d8191548ea..b55b61907e08ab5f297e6995fa0164652d476cd3 100755 (executable)
--- a/main.py
+++ b/main.py
@@ -26,6 +26,8 @@ os.environ['BUP_RESOURCE_PATH'] = resourcepath
 from bup import helpers
 from bup.helpers import *
 
+# after running 'bup newliner', the tty_width() ioctl won't work anymore
+os.environ['WIDTH'] = str(tty_width())
 
 def usage():
     log('Usage: bup [-?|--help] [-d BUP_DIR] [--debug] '