update packages

[CreaPhase.git] / octave_packages / m / pkg / private / get_forge_pkg.m

diff --git a/octave_packages/m/pkg/private/get_forge_pkg.m b/octave_packages/m/pkg/private/get_forge_pkg.m
new file mode 100644 (file)
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+++ b/octave_packages/m/pkg/private/get_forge_pkg.m
@@ -0,0 +1,81 @@
+## Copyright (C) 2010-2012 VZLU Prague, a.s.
+##
+## This file is part of Octave.
+##
+## Octave 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 3 of the License, or (at
+## your option) any later version.
+##
+## Octave 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 Octave; see the file COPYING.  If not, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{ver}, @var{url}] =} get_forge_pkg (@var{name})
+## Try to discover the current version of an OctaveForge package from the web,
+## using a working internet connection and the urlread function.
+## If two output arguments are requested, also return an address from which
+## to download the file.
+## @end deftypefn
+
+function [ver, url] = get_forge_pkg (name)
+  if (nargin != 1)
+    print_usage ();
+  endif
+  ## Verify that name is valid.
+  if (! (ischar (name) && rows (name) == 1 && ndims (name) == 2))
+    error ("get_forge_pkg: package NAME must be a string");
+  elseif (! all (isalnum (name) | name == "-" | name == "." | name == "_"))
+    error ("get_forge_pkg: invalid package name: %s", name);
+  endif
+
+  name = tolower (name);
+
+  ## Try to download package's index page.
+  [html, succ] = urlread (sprintf ("http://octave.sourceforge.net/%s/index.html", name));
+  if (succ)
+    ## Remove blanks for simpler matching.
+    html(isspace(html)) = [];
+    ## Good. Let's grep for the version.
+    pat = "<tdclass=""package_table"">PackageVersion:</td><td>([\\d.]*)</td>";
+    t = regexp (html, pat, "tokens");
+    if (isempty (t) || isempty(t{1}))
+      error ("get_forge_pkg: could not read version number from package's page");
+    else
+      ver = t{1}{1};
+      if (nargout > 1)
+        # Build download string.
+        urlbase = "http://downloads.sourceforge.net/octave/%s-%s.tar.gz?download";
+        url = sprintf (urlbase, name, ver);
+        ## Verify that the string exists on the page.
+        if (isempty (strfind (html, url)))
+          warning ("get_forge_pkg: download URL not verified");
+        endif
+      endif
+    endif
+  else
+    ## Try get the list of all packages.
+    [html, succ] = urlread ("http://octave.sourceforge.net/packages.php");
+    if (succ)
+      t = regexp (html, "<div class=""package"" id=""(\\w+)"">", "tokens");
+      t = horzcat (t{:});
+      if (any (strcmp (t, name)))
+        error ("get_forge_pkg: package NAME exists, but index page not available");
+      else
+        ## Try a simplistic method to determine close names.
+        dist = cellfun (@(n) length (setdiff (name, n)), t);
+        [~, i] = min (dist);
+        error ("get_forge_pkg: package not found: ""%s"". Maybe you meant ""%s?""", name, t{i});
+      endif
+    else
+      error ("get_forge_pkg: could not read URL, please verify internet connection");
+    endif
+  endif
+
+endfunction