--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/share/lua/5.2/luarocks/tools/zip.lua	Fri Dec 14 22:24:27 2012 +0000
@@ -0,0 +1,245 @@
+
+--- A Lua implementation of .zip file archiving (used for creating .rock files),
+-- using only lua-zlib.
+module("luarocks.tools.zip", package.seeall)
+
+local zlib = require("zlib")
+local fs = require("luarocks.fs")
+local dir = require("luarocks.dir")
+
+local function number_to_bytestring(number, nbytes)
+   local out = {}
+   for i = 1, nbytes do
+      local byte = number % 256
+      table.insert(out, string.char(byte))
+      number = (number - byte) / 256
+   end
+   return table.concat(out)
+end
+
+--- Begin a new file to be stored inside the zipfile.
+-- @param self handle of the zipfile being written.
+-- @param filename filenome of the file to be added to the zipfile.
+-- @return true if succeeded, nil in case of failure.
+local function zipwriter_open_new_file_in_zip(self, filename)
+   if self.in_open_file then
+      self:close_file_in_zip()
+      return nil
+   end
+   local lfh = {}
+   self.local_file_header = lfh
+   lfh.last_mod_file_time = 0 -- TODO
+   lfh.last_mod_file_date = 0 -- TODO
+   lfh.crc32 = 0 -- initial value
+   lfh.compressed_size = 0 -- unknown yet
+   lfh.uncompressed_size = 0 -- unknown yet
+   lfh.file_name_length = #filename
+   lfh.extra_field_length = 0
+   lfh.file_name = filename:gsub("\\", "/")
+   lfh.external_attr = 0 -- TODO properly store permissions
+   self.in_open_file = true
+   self.data = {}
+   return true
+end
+
+--- Write data to the file currently being stored in the zipfile.
+-- @param self handle of the zipfile being written.
+-- @param buf string containing data to be written.
+-- @return true if succeeded, nil in case of failure.
+local function zipwriter_write_file_in_zip(self, buf)
+   if not self.in_open_file then
+      return nil
+   end
+   local lfh = self.local_file_header
+   local cbuf = zlib.compress(buf):sub(3, -5)
+   lfh.crc32 = zlib.crc32(lfh.crc32, buf)
+   lfh.compressed_size = lfh.compressed_size + #cbuf
+   lfh.uncompressed_size = lfh.uncompressed_size + #buf
+   table.insert(self.data, cbuf)
+   return true
+end
+
+--- Complete the writing of a file stored in the zipfile.
+-- @param self handle of the zipfile being written.
+-- @return true if succeeded, nil in case of failure.
+local function zipwriter_close_file_in_zip(self)
+   local zh = self.ziphandle
+   
+   if not self.in_open_file then
+      return nil
+   end
+
+   -- Local file header
+   local lfh = self.local_file_header
+   lfh.offset = zh:seek()
+   zh:write(number_to_bytestring(0x04034b50, 4)) -- signature
+   zh:write(number_to_bytestring(20, 2)) -- version needed to extract: 2.0
+   zh:write(number_to_bytestring(0, 2)) -- general purpose bit flag
+   zh:write(number_to_bytestring(8, 2)) -- compression method: deflate
+   zh:write(number_to_bytestring(lfh.last_mod_file_time, 2))
+   zh:write(number_to_bytestring(lfh.last_mod_file_date, 2))
+   zh:write(number_to_bytestring(lfh.crc32, 4))
+   zh:write(number_to_bytestring(lfh.compressed_size, 4))
+   zh:write(number_to_bytestring(lfh.uncompressed_size, 4))
+   zh:write(number_to_bytestring(lfh.file_name_length, 2))
+   zh:write(number_to_bytestring(lfh.extra_field_length, 2))
+   zh:write(lfh.file_name)
+
+   -- File data   
+   for _, cbuf in ipairs(self.data) do
+      zh:write(cbuf)
+   end
+   
+   -- Data descriptor
+   zh:write(number_to_bytestring(lfh.crc32, 4))
+   zh:write(number_to_bytestring(lfh.compressed_size, 4))
+   zh:write(number_to_bytestring(lfh.uncompressed_size, 4))
+   
+   table.insert(self.files, lfh)
+   self.in_open_file = false
+   
+   return true
+end
+
+-- @return boolean or (boolean, string): true on success,
+-- false and an error message on failure.
+local function zipwriter_add(self, file)
+   local fin
+   local ok, err = self:open_new_file_in_zip(file)
+   if not ok then
+      err = "error in opening "..file.." in zipfile"
+   else
+      fin = io.open(fs.absolute_name(file), "rb")
+      if not fin then
+         ok = false
+         err = "error opening "..file.." for reading"
+      end
+   end
+   if ok then
+      local buf = fin:read("*a")
+      if not buf then
+         err = "error reading "..file
+         ok = false
+      else
+         ok = self:write_file_in_zip(buf)
+         if not ok then
+            err = "error in writing "..file.." in the zipfile"
+         end
+      end
+   end
+   if fin then
+      fin:close()
+   end
+   if ok then
+      ok = self:close_file_in_zip()
+      if not ok then
+         err = "error in writing "..file.." in the zipfile"
+      end
+   end
+   return ok == true, err
+end
+
+--- Complete the writing of the zipfile.
+-- @param self handle of the zipfile being written.
+-- @return true if succeeded, nil in case of failure.
+local function zipwriter_close(self)
+   local zh = self.ziphandle
+   
+   local central_directory_offset = zh:seek()
+   
+   local size_of_central_directory = 0
+   -- Central directory structure
+   for _, lfh in ipairs(self.files) do
+      zh:write(number_to_bytestring(0x02014b50, 4)) -- signature
+      zh:write(number_to_bytestring(3, 2)) -- version made by: UNIX
+      zh:write(number_to_bytestring(20, 2)) -- version needed to extract: 2.0
+      zh:write(number_to_bytestring(0, 2)) -- general purpose bit flag
+      zh:write(number_to_bytestring(8, 2)) -- compression method: deflate
+      zh:write(number_to_bytestring(lfh.last_mod_file_time, 2))
+      zh:write(number_to_bytestring(lfh.last_mod_file_date, 2))
+      zh:write(number_to_bytestring(lfh.crc32, 4))
+      zh:write(number_to_bytestring(lfh.compressed_size, 4))
+      zh:write(number_to_bytestring(lfh.uncompressed_size, 4))
+      zh:write(number_to_bytestring(lfh.file_name_length, 2))
+      zh:write(number_to_bytestring(lfh.extra_field_length, 2))
+      zh:write(number_to_bytestring(0, 2)) -- file comment length
+      zh:write(number_to_bytestring(0, 2)) -- disk number start
+      zh:write(number_to_bytestring(0, 2)) -- internal file attributes
+      zh:write(number_to_bytestring(lfh.external_attr, 4)) -- external file attributes
+      zh:write(number_to_bytestring(lfh.offset, 4)) -- relative offset of local header
+      zh:write(lfh.file_name)
+      size_of_central_directory = size_of_central_directory + 46 + lfh.file_name_length
+   end
+   
+   -- End of central directory record
+   zh:write(number_to_bytestring(0x06054b50, 4)) -- signature
+   zh:write(number_to_bytestring(0, 2)) -- number of this disk
+   zh:write(number_to_bytestring(0, 2)) -- number of disk with start of central directory
+   zh:write(number_to_bytestring(#self.files, 2)) -- total number of entries in the central dir on this disk
+   zh:write(number_to_bytestring(#self.files, 2)) -- total number of entries in the central dir
+   zh:write(number_to_bytestring(size_of_central_directory, 4))
+   zh:write(number_to_bytestring(central_directory_offset, 4))
+   zh:write(number_to_bytestring(0, 2)) -- zip file comment length
+   zh:close()
+
+   return true
+end
+
+--- Return a zip handle open for writing.
+-- @param name filename of the zipfile to be created.
+-- @return a zip handle, or nil in case of error.
+function new_zipwriter(name)
+   
+   local zw = {}
+  
+   zw.ziphandle = io.open(fs.absolute_name(name), "wb")
+   if not zw.ziphandle then
+      return nil
+   end
+   zw.files = {}
+   zw.in_open_file = false
+   
+   zw.add = zipwriter_add
+   zw.close = zipwriter_close
+   zw.open_new_file_in_zip = zipwriter_open_new_file_in_zip
+   zw.write_file_in_zip = zipwriter_write_file_in_zip
+   zw.close_file_in_zip = zipwriter_close_file_in_zip
+
+   return zw
+end
+
+--- Compress files in a .zip archive.
+-- @param zipfile string: pathname of .zip archive to be created.
+-- @param ... Filenames to be stored in the archive are given as
+-- additional arguments.
+-- @return boolean or (boolean, string): true on success,
+-- false and an error message on failure.
+function zip(zipfile, ...)
+   local zw = new_zipwriter(zipfile)
+   if not zw then
+      return nil, "error opening "..zipfile
+   end
+
+   local ok, err
+   for _, file in pairs({...}) do
+      if fs.is_dir(file) then
+         for _, entry in pairs(fs.find(file)) do
+            local fullname = dir.path(file, entry)
+            if fs.is_file(fullname) then
+               ok, err = zw:add(fullname)
+               if not ok then break end
+            end
+         end
+      else
+         ok, err = zw:add(file)
+         if not ok then break end
+      end
+   end
+
+   local ok = zw:close()
+   if not ok then
+      return false, "error closing "..zipfile
+   end
+   return ok, err
+end
+