1. Introduction
   1.1. Project/Component Working Name:

        w3m  a text-based WWW browser

   1.2. Name of Document Author/Supplier:
        
        Author:         Rick Ju
        Sponser:        Irene Huang

   1.3. Date of This Document:

        05/11/2008

2. Technical Description:
    2.1. Details:
     
     w3m is a text-based web browser as well as a pager like `more' or `less'.
     With w3m you can browse web pages through a terminal emulator window
     (xterm, rxvt or something like that).  Moreover, w3m can be used as a
     text formatting tool which typesets HTML into plain text.

     w3m has support for tables, frames, SSL connections, color and even inline
     images on suitable terminals. Generally, it renders pages in a form as true
     to their original layout as possible.  And W3m is small. Its stripped
     binary for Sparc is only 260kbyte.

     w3m locally run cgi scripts to test html output (requires *no* webserver).
     w3m keystroke compatible with lynx and support the keybindings customize.
     w3m support SSL through the openssl library. And w3m could support cookies.

     Table rendering algorithm in w3m

     HTML table rendering is difficult. Tabular environment of LaTeX is not very
     difficult, which makes the width of a column either a specified value or
     the maximum width to put items into it. On the other hand, HTML table
     renderer has to decide the width of a column so that the entire table can
     fit into the display appropriately, and fold the contents of the table
     according to the column width.  Inappropriate column width decision makes
     the table ugly.  Moreover, table can be nested, which makes the algorithm
     more complicated.

     1. First, calculate the maximum and minimum width of each column. The
        maximum width is the width required to display the column without
        folding the contents. Generally, it is the length of paragraph
        delimited by <BR> or <P>. The minimum width is the lower limit
        to display the contents.  If the column contains the word
        `internationalization', the minimum width will be 20. If the column
        contains <pre>..</pre>, the maximum width of the preformatted
        text will be the minimum width of the column.  2. If the width of
        the column is specified by WIDTH attribute, fix the column
        width using that value. If the specified width is smaller than the
        minimum width of the column, fix the column width to the minimum
        width.

     3. Calculate the sum of the maximum width (or fixed width) of each column
        and check if the sum exceeds the screen width. If it is smaller than
        screen width, these values are used for width of each column.

     4. If the sum is larger than the screen width, determine the widths of
        each column according to the following steps.
         1. Let W be the screen width subtracted by the sum of widths of
            fixed-width columns.
         2. Distribute W into the columns whose width are not decided, in
            proportion to the logarithm of the maximum width of each column.
         3. If the distributed width of a column is smaller than the minimum
            width, then fix the width of the column to the minimum width,
            and do the distribution again. 

    In this process, distributed width is proportion to logarithm of maximum width.

    The algorithm above assumes that the screen width is known. But it is not
    true for nested table. According the algorithm above, the column width of
    the outer table have to be known to render the inner table, while the total
    width of the inner table have to be known to determine the column width of
    the outer table. If WIDTH attribute exists there are no problems.
    Otherwise, w3m assumes that the inner table is 0.8 times as wide as the
    outer table. It works fine, but if there are two tables side by side in an
    outer table, the width of the outer table always exceeds the screen width.
    To render this kind of table correctly, one have to render the table once,
    check the width of outmost table, and then render the entire table again.
    Netscape might employ this kind of algorithm.

    2.2. Interfaces:
           Exported Interfaces
                Interface        Classification    Comments
                --------------- ---------------    -----------------------
                w3m CLI           Volatile         See w3m-help.txt

                $HOME/.w3m/config Project Private  w3m Configuration information
                SUNWw3m           Uncommited       w3m end-user packaging contains binary, libraries.
                SUNWw3m-l10n      Uncommited       Localization.

        Imported Interfaces
                Interface        Classification        Comments
                --------------- --------------- -----------------------
                HTML/XML/HTTP       Stable           These specs are defined
                                                     W 3C.org
                OpenSSL             Volatile         PSARC/2003/500
                Firefox             Volatile         LSARC/2008/158
                GTK+                Committed        LSARC/2006/202
                libpng              Volatile         LSARC/2006/202

    2.3. Doc Impact:
    
         Man page is needed.
     
    2.4. Packaging & Delivery:
         SUNWw3m (base package)             - application i.e binary, libraries
         SUNWw3m-l10n (localization)        - Localization.

   
    2.5. Dependencies:
         w3m depends on OpenSSL, Firefox, GTK+, and libpng.
        
    2.6. L10N Impact:
         There are string changes. Hence this should be taken care.

    2.7 Security Impact:

        None.