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Overview
Comment:Use Wapp to implement the search function. Search can now be run from the command-line using "./tclsh.docsrc doc/search".
Timelines: family | ancestors | descendants | both | search-refactor
Files: files | file ages | folders
SHA3-256: 33c56bee814568abd863f684f92fdafe8d8a1407d7ba944e4eab73ab7c89aa70
User & Date: drh 2018-02-04 21:41:59
Context
2018-02-04
23:30
Add the search.d/admin script. check-in: 685371e833 user: drh tags: search-refactor
21:41
Use Wapp to implement the search function. Search can now be run from the command-line using "./tclsh.docsrc doc/search". check-in: 33c56bee81 user: drh tags: search-refactor
2018-02-01
14:44
Merge fixes from the release branch. check-in: 5279eb6057 user: drh tags: trunk
Changes
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Changes to main.mk.

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# Flags to build [tclsqlite3.search] with.
#
SFLAGS = $(TCLINC) -DSQLITE_THREADSAFE=0 -DSQLITE_ENABLE_FTS5 -DSQLITE_TCLMD5 -DTCLSH -Dmain=xmain

$(TCLSH): $(SSRC)
	$(CC) -O2 -o $@ -I. $(SFLAGS) $(SSRC) $(TCLFLAGS)





searchdb: $(TCLSH)
	mkdir -p doc/search.d/
	./$(TCLSH) $(DOC)/search/buildsearchdb.tcl
	cp $(DOC)/document_header.tcl doc/document_header.tcl
	cp $(DOC)/document_header.tcl doc/search.d/document_header.tcl
	cp $(DOC)/search/search.tcl doc/search
	chmod +x doc/search

	cp $(DOC)/search/search.tcl doc/search.d/admin
	chmod +x doc/search.d/admin

fts5ext.so:	$(DOC)/search/fts5ext.c
	gcc -shared -fPIC -I. -DSQLITE_EXT \
		$(DOC)/search/fts5ext.c -o fts5ext.so

# Build the "docapp" application by adding an appropriate SQLAR
# repository onto the end of the "sqltclsh" application.  







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# Flags to build [tclsqlite3.search] with.
#
SFLAGS = $(TCLINC) -DSQLITE_THREADSAFE=0 -DSQLITE_ENABLE_FTS5 -DSQLITE_TCLMD5 -DTCLSH -Dmain=xmain

$(TCLSH): $(SSRC)
	$(CC) -O2 -o $@ -I. $(SFLAGS) $(SSRC) $(TCLFLAGS)

doc/search:	$(TCLSH) $(DOC)/search/mkscript.tcl $(DOC)/search/search.tcl.in $(DOC)/search/wapp.tcl $(DOC)/document_header.tcl
	./$(TCLSH) $(DOC)/search/mkscript.tcl $(DOC)/search/search.tcl.in >doc/search
	chmod +x doc/search

searchdb: $(TCLSH) doc/search
	mkdir -p doc/search.d/
	./$(TCLSH) $(DOC)/search/buildsearchdb.tcl





#	cp $(DOC)/search/search.tcl doc/search.d/admin
#	chmod +x doc/search.d/admin

fts5ext.so:	$(DOC)/search/fts5ext.c
	gcc -shared -fPIC -I. -DSQLITE_EXT \
		$(DOC)/search/fts5ext.c -o fts5ext.so

# Build the "docapp" application by adding an appropriate SQLAR
# repository onto the end of the "sqltclsh" application.  

Deleted search/buildsearchdb4.tcl.

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load ./parsehtml.so

#=========================================================================
# Return a list of relative paths to documents that should be included 
# in the index.
#
proc document_list {} {
  set files [list]
  foreach f [glob *.html c3ref/*.html releaselog/*.html] {
    if {![string match *crossref* $f]
     && ![string match fileio.html $f]
     && ![string match capi3ref.html $f]
     && ![string match changes.html $f]
     && ![string match btreemodule.html $f]
    } { lappend files $f }
  }
  return $files
}

#=========================================================================
# Read and return the contents of text file $zFile.
#
proc readfile {zFile} {
  set fd [open $zFile]
  set ret [read $fd]
  close $fd
  return $ret
}

#=========================================================================
# [parsehtml] callback used for parsing keywords.html...
#
proc keywordparse_callback {tag details} {
  global K P
  switch -- [string tolower $tag] {
    "" {
      if {[info exists K(hyperlink)]} {
        append K($K(hyperlink)) $details
      }
    }
    "a" {
      array set D $details
      if {[info exists D(href)]} { set K(hyperlink) $D(href) }
    }
    "/a" {
      unset -nocomplain P(hyperlink)
    }
  }
}

#=========================================================================
# This function is used as the callback when parsing ordinary documents 
# (not the keywords document).
#
# Rules for extracting fragment "titles". A fragment title consists of
# all text that follows the tag that opens the fragment until either:
#
#   1. 80 characters have been parsed, or
#   2. 8 characters have been parsed and one of the following is 
#        encountered:
#      a) A block element opening or closing tag, or
#      b) A <br> element, or
#      c) A "." character.
#
#   3. 8 characters have been parsed and a <br> tag or "." character is
#      encountered
#
proc docparse_callback {tag details} {
  global P
  set tag [string tolower $tag]
  switch -glob -- $tag {
    "" {
      append P(text) " $details"
      if {$P(isTitle)} { append P(title) $details }
      if {[llength $P(fragments)]} { 
        append P(ftext) " $details" 
      }
    }

    "title"  { set P(isTitle) 1 }
    "/title" { set P(isTitle) 0 }

    "a" { 
      array set D $details
      if {[info exists D(name)]} {
        if {[llength $P(fragments)]} { 
          lappend P(fragments) $P(ftitle) $P(ftext) 
        }
        lappend P(fragments) $D(name)
        set P(ftext) ""
        set P(ftitle) ""
        catch { unset P(ftitleclose) }
      }
    }
    "h*" {
      array set D $details
      if {[info exists D(id)]} {
        if {[llength $P(fragments)]} { 
          lappend P(fragments) $P(ftitle) $P(ftext) 
        }
        lappend P(fragments) $D(id)
        set P(ftext) ""
        set P(ftitle) ""
      }
    }

    div {
      array set D $details
      if {[info exists D(class)] && $D(class) == "startsearch"} { 
        set P(text) "" 
      }
    }
  }

  set ftext [string trim $P(ftext) " \v\n"]
  if {[string length $ftext]>4 && $P(ftitle) == ""} {
    set blocktags [list                               \
      br td /td th /th p /p                           \
      h1 h2 h3 h4 h5 h /h1 /h2 /h3 /h4 /h5 /h
    ]
    if {[lsearch $blocktags $tag]>=0} {
      set P(ftitle) $ftext
      set P(ftext)  ""
    } elseif {[string length $ftext]>80} {
      set idx [string last " " [string range $ftext 0 79]]
      if {$idx<0} { set idx 80 }
      set P(ftitle) [string range $ftext 0 [expr $idx-1]]
      set P(ftext)  [string range $ftext $idx end]
    } 
  }
}

proc findlinks_callback {tag details} {
  global P
  set doc $P(doc)

  set tag [string tolower $tag]
  switch -glob -- $tag {
    a {
      array set D $details
      if {[info exists D(href)]} {
        if { [string range $D(href) 0 0]=="#" } {
          set url "${doc}$D(href)"
        } else {
          set url "$D(href)"
        }

        set P(url) $url
        set P(link) ""
      }
    }
    /a {
      if {$P(url)!=""} {
        db eval { UPDATE pagedata SET links = links || ' ' || $P(link) WHERE url=$P(url) }
      }
      set P(url) ""
      set P(link) ""
    }

    "" {
      append P(link) " $details"
    }
  }
}

proc trim {a} {
  set L [split $a]
  return [lsort -uniq $L]
}

#=========================================================================
# Build the database.
#
proc rebuild_database {} {

  db transaction {
    db eval {
      DROP TABLE IF EXISTS pagedata;
      CREATE TABLE pagedata(
        url TEXT PRIMARY KEY,     -- Relative URL for this document
        links,                    -- Text of all links to this URI
        title,                    -- Document or fragment title
        content                   -- Document or fragment content
      );
    }

    # Scan the file-system for HTML documents. Add each document found to
    # the page and pagedata tables.
    foreach file [document_list] {
      set zHtml [readfile $file]

      array unset ::P
      set ::P(text) ""                 ;# The full document text
      set ::P(isTitle) 0               ;# True while parsing contents of <title>
      set ::P(fragments) [list]        ;# List of document fragments parsed
      set ::P(ftext) ""                ;# Text of current document fragment 

      parsehtml $zHtml docparse_callback
      if {[info exists ::P(ftitle)]} {
        lappend ::P(fragments) $::P(ftitle) $::P(ftext)
      }

      set keyword ""
      catch { set keyword $::K($file) }
      if {![info exists ::P(title)]} {set ::P(title) "No Title"}
      db eval { REPLACE INTO pagedata VALUES($file, '', $::P(title), $::P(text)) }

      foreach {name title text} $::P(fragments) {
        set url "$file#$name"
        puts $url
        db eval { REPLACE INTO pagedata VALUES($url, '', $title, $text) }
      }
    }

    foreach file [document_list] {
      set zHtml [readfile $file]

      array unset ::P
      set ::P(url) ""
      set ::P(doc) $file
      parsehtml $zHtml findlinks_callback
    }

    db func trim trim
    #db eval { UPDATE pagedata SET links = trim(links) }
    db eval { CREATE INDEX ft ON pagedata USING fts5() }
  }
}

sqlite4 db search4.db
rebuild_database

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Added search/mkscript.tcl.













































































































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#!/usr/bin/tclsh
#
# Use this script to build the TCL scripts that implement the search
# functions on the SQLite website.
#
# Usage example:
#
#     tclsh mkscript.tcl search.tcl.in >search.tcl
#
# The input to this script is a template script file, named something
# like "search.tcl.in".  This script reads the template line-by-line and
# applies some minor transformations:
#
#     INCLUDE filename         Lines match this pattern are replaced
#                              by the complete text of filename.  This
#                              is used (for example) to insert the
#                              complete text of wapp.tcl in the appropriate
#                              place CGI scripts
#
#     DOCHEADER title path     Lines matching this pattern invoke the
#                              document_header function contained in the
#                              ../document_header.tcl file to generate
#                              header text for the document, and then
#                              insert that header text in place of the
#                              line
#
# Other than these transformations, the input is copied through into
# the output.
#
if {[llength $argv]!=1} {
  puts stderr "Usage: $argv0 TEMPLATE >OUTPUT"
  exit 1
}
set infile [lindex $argv 0]
set ROOT [file dir [file dir [file normalize $argv0]]]
set HOME [file dir [file normalize $infile]]
set in [open $infile rb]
while {1} {
  set line [gets $in]
  if {[eof $in]} break
  if {[regexp {^INCLUDE (.*)} $line all path]} {
    set in2 [open $HOME/$path rb]
    puts [read $in2]
    close $in2
    continue
  }
  if {[regexp {^DOCHEAD } $line] && [llength $line]==3} {
    source $ROOT/document_header.tcl
    puts [document_header [lindex $line 1] [lindex $line 2]]
    continue
  }
  puts $line
}
close $in

Deleted search/search.tcl.

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#!/usr/bin/tclsh.docsrc

source [file dirname [info script]]/document_header.tcl

# Decode an HTTP %-encoded string
#
proc percent_decode {str} {
    # rewrite "+" back to space
    # protect \ and [ and ] by quoting with '\'
    set str [string map [list + { } "\\" "\\\\" \[ \\\[ \] \\\]] $str]

    # prepare to process all %-escapes
    regsub -all -- {%([A-Fa-f][A-Fa-f0-9])%([A-Fa-f89][A-Fa-f0-9])} \
        $str {[encoding convertfrom utf-8 [binary decode hex \1\2]]} str
    regsub -all -- {%([0-7][A-Fa-f0-9])} $str {\\u00\1} str

    # process %-escapes
    return [subst -novar $str]
}

#=========================================================================
# This proc is called to parse the arguments passed to this invocation of
# the CGI program (via either the GET or POST method). It returns a
# key/value list containing the arguments suitable for passing to [array
# set]. For example, if the CGI is invoked via a GET request on the URI:
#
#   http://www.sqlite.org/search?query=fts3+table&results=10
#
# then the returned list value is: 
#
#   {query {fts3 table} results 10}
#
proc cgi_parse_args {} {
  global env A

  if {$env(REQUEST_METHOD) == "GET"} {
    foreach q [split $env(QUERY_STRING) &] {
      if {[regexp {([a-z0-9]*)=(.*)} $q all var value]} {
        set A($var) [percent_decode $value]
      }
    }
  } elseif {$env(REQUEST_METHOD) == "POST"} {
    set qstring [read stdin $env(CONTENT_LENGTH)]
    foreach q [split $qstring &] {
      if {[regexp {([a-z0-9]*)=(.*)} $q all var value]} {
        set A($var) [percent_decode $value]
      }
    }
  } else {
    error "Unrecognized method: $env(REQUEST_METHOD)"
  }
}


#=========================================================================
# The argument contains a key value list. The values in the list are
# transformed to an HTTP query key value list. For example:
#
#   % cgi_encode_args {s "search string" t "search \"type\""}
#   s=search+string&t=search+%22type%22
#
proc cgi_encode_args {list} {
  set reslist [list]
  foreach {key value} $list {
    set value [string map {
      \x20 +   \x21 %21 \x2A %2A \x22 %22 \x27 %27 \x28 %28 \x29 %29 \x3B %3B 
      \x3A %3A \x40 %40 \x26 %26 \x3D %3D \x2B %2B \x24 %24 \x2C %2C \x2F %2F 
      \x3F %3F \x25 %25 \x23 %23 \x5B %5B \x5D %5D
    } $value]

    lappend reslist "$key=$value"
  }
  join $reslist &
}

proc htmlize {str} { string map {< &lt; > &gt;} $str }
proc attrize {str} { string map {< &lt; > &gt; \x22 &quot;} $str }

#=========================================================================

proc cgi_env_dump {} {

  set ret "<h1>Arguments</h1><table>"
  foreach {key value} [array get ::A] {
    append ret "<tr><td>[htmlize $key]<td>[htmlize $value]"
  }
  append ret "</table>"

  append ret "<h1>Environment</h1><table>"
  foreach {key value} [array get ::env] {
    append ret "<tr><td>[htmlize $key]<td>[htmlize $value]"
  }
  append ret "</table>"
  return $ret
}

#-------------------------------------------------------------------------
# Add an entry to the log database for the current query. Which 
# returns $nRes results.
#
proc search_add_log_entry {nRes} {
  if {[info exists ::A(donotlog)]} return

  sqlite3 db2 search.d/searchlog.db
  db2 timeout 10000

  set ip $::env(REMOTE_ADDR)
  set query $::A(q)

  db2 eval {
    PRAGMA synchronous=OFF;
    PRAGMA journal_mode=OFF;
    BEGIN;
      CREATE TABLE IF NOT EXISTS log(
        ip,                  -- IP query was made from
        query,               -- Fts5 query string
        nres,                -- Number of results
        timestamp DEFAULT CURRENT_TIMESTAMP
      );
      INSERT INTO log(ip, query, nres) VALUES($ip, $query, $nRes);
    COMMIT;
  }

  db2 close
}

proc sqlize {text} {
  return "'[string map [list ' ''] $text]'"
}

proc admin_list {} {
  sqlite3 db2 searchlog.db

  set where ""
  set res ""

  set ipfilter ""
  if {[info exists ::A(ip)] && $::A(ip)!=""} {
    set where "WHERE ip = [sqlize $::A(ip)]"
    set ipfilter $::A(ip)
  }

  set checked ""
  if {[info exists ::A(unique)] && $::A(unique)} {
    set checked "checked"
  }

  set limit 10
  if {[info exists ::A(limit)]} {
    set limit $::A(limit)
  }
  set s10 ""
  set s100 ""
  set s1000 ""
  if {$limit==10} {set s10 selected}
  if {$limit==100} {set s100 selected}
  if {$limit==1000} {set s1000 selected}

  append res "
    <div style=\"margin:2em\">
    <center>
    <form action=admin method=get>
      Results: <select name=limit onChange=\"this.form.submit()\">
        <option $s10 value=\"10\">10</option>
        <option $s100 value=\"100\">100</option>
        <option $s1000 value=\"1000\">1000</option>
      </select>
      IP: <input type=input name=ip value=\"[attrize $ipfilter]\"> 
      Unique: <input 
        type=checkbox name=unique value=1 
        $checked
        onChange=\"this.form.submit()\"
      >
      <input type=submit>
    </form>
    </center>
    </div>
  "

  set i 0
  append res "<table border=1 cellpadding=10 align=center>\n"
  append res "<tr><td><th>IP <th>Query <th> Results <th> Timestamp\n"
  db2 eval "
    SELECT rowid, ip, query, nres, timestamp FROM log $where
    ORDER BY rowid DESC
  " {

    if {[info exists ::A(unique)] && $::A(unique)} {
      if {[info exists seen($query)]} continue
      set seen($query) 1
    }

    set querylink "<a href=\"../search?q=[attrize $query]&donotlog=1\">$query</a>"
    set iplink "<a href=\"?admin=1&ip=$ip\">$ip</a>"

    append res "  <tr> <td> $rowid <td> $iplink <td> $querylink"
    append res "       <td> $nres <td> $timestamp\n"

    incr i
    if {$i >= $limit} break
  }
  append res "</table>\n"

  return $res
}


#-------------------------------------------------------------------------
# This command is similar to the builtin Tcl [time] command, except that
# it only ever runs the supplied script once. Also, instead of returning
# a string like "xxx microseconds per iteration", it returns "x.yy ms" or
# "x.yy s", depending on the magnitude of the time spent running the 
# command. For example:
#
#   % ttime {after 1500}
#   1.50 s
#   % ttime {after 45}
#   45.02 ms
#
proc ttime {script} {
  set t [lindex [time [list uplevel $script]] 0]
  if {$t>1000000} { return [format "%.2f s" [expr {$t/1000000.0}]] }
  return [format "%.2f ms" [expr {$t/1000.0}]]
}

proc searchchanges {} {
  global A
  if {![info exists A(q)]} return ""

  set open {<span style="background-color:#d9f2e6">}
  set close {</span>}
  set query {
    SELECT url, version, idx, highlight(change, 3, $open, $close) AS text 
    FROM change($A(q)) ORDER BY rowid ASC
  }

  set ret [subst {
    <p>Change log entries mentioning: <b>[htmlize $::A(q)]</b>
    <table border=0>
  }]

  set s2 "style=\"margin-top:0\""
  set s1 "style=\"font-size:larger; text-align:left\" class=nounderline"
  set prev ""
  db eval $query {
    if {$prev!=$version} {
      append ret [subst {
        <tr> <td $s1 valign=top> <a href=$url>$version</a> <td> <ul $s2>
      }]
      set prev $version
    }
    append ret [subst { <li value=$idx> ($idx) $text }]
  }

  append ret "</table>"
  append ret "<center><p>You can also see the <a href=changes.html>entire"
  append ret " changelog as a single page</a> if you wish.</center>"

  return $ret
}

proc searchresults {} {
  if {![info exists ::A(q)]} return ""
  #set ::A(q) [string map {' ''} $A(q)]
  #regsub -all {[^-/"A-Za-z0-9]} $::A(q) { } ::A(q)

  # Count the '"' characters in $::A(q). If there is an odd number of
  # occurences, add a " to the end of the query so that fts5 can parse
  # it without error.
  if {[regexp -all \x22 $::A(q)] % 2} { append ::A(q) \x22 }

  # Set iStart to the index of the first result to display. Results are
  # indexed starting at zero from most to least relevant.
  #
  set iStart [expr {([info exists ::A(i)] ? $::A(i) : 0)*10}]

  # Grab a list of rowid results.
  #
  set q {
    SELECT rowid FROM page WHERE page MATCH $::A(q) 
    ORDER BY srank(page) DESC,
    rank * COALESCE(
      (SELECT percent FROM weight WHERE id=page.rowid), 100
    );
  }
  if {[catch { set lRowid [db eval $q] }]} {
    set x ""
    foreach word [split $::A(q) " "] {
      append x " \"[string map [list "\"" "\"\""] $word]\""
    }
    set ::A(q) [string trim $x]
    set lRowid [db eval $q]
  }

  set lRes [list]
  foreach rowid $lRowid {
    if {$rowid > 1000} {
      set parent [expr $rowid / 1000]
      lappend subsections($parent) $rowid
    } else {
      lappend lRes $rowid
    }
  }

  set nRes [llength $lRes]
  set lRes [lrange $lRes $iStart [expr $iStart+9]]

  # Add an entry to the log database.
  #
  search_add_log_entry $nRes

  # If there are no results, return a message to that effect.
  #
  if {[llength $lRes] == 0} {
    return [subst { No results for: <b>[htmlize $::A(q)]</b> }]
  }
  
  # HTML markup used to highlight keywords within FTS5 generated snippets.
  #
  set open {<span style="background-color:#d9f2e6">}
  set close {</span>}
  set ellipsis {<b>&nbsp;...&nbsp;</b>}

  # Grab the required data
  #
  db eval [string map [list %LIST% [join $lRowid ,]] {
    SELECT 
      rowid AS parentid, 
      snippet(page, 0, $open, $close, $ellipsis, 6)  AS s_apis,
      snippet(page, 2, $open, $close, '', 40)        AS s_title1,
      snippet(page, 3, $open, $close, $ellipsis, 40) AS s_title2,
      snippet(page, 4, $open, $close, $ellipsis, 40) AS s_content,
      url, rank
    FROM page($::A(q))
    WHERE rowid IN (%LIST%)
  }] X {
    foreach k [array names X] { set data($X(parentid),$k) [set X($k)] }
  }

  set ret [subst {
    <table border=0>
    <p>Search results 
       [expr $iStart+1]..[expr {($nRes < $iStart+10) ? $nRes : $iStart+10}] 
       of $nRes for: <b>[htmlize $::A(q)]</b>
  }]

  foreach rowid $lRes {

    foreach a {parentid s_apis s_title1 s_content url rank} {
      set $a $data($rowid,$a)
    }

    if {[info exists subsections($parentid)]} {
      set childid [lindex $subsections($parentid) 0]
      set link $data($childid,url)
      set hdr $data($childid,s_title2)

      if {$hdr==""} {
        set s_content ""
      } else {
        set s_content [subst {
          <b><a style=color:#044a64 href=$link>$hdr</a></b>
        }]
      }

      append s_content " $data($childid,s_content)"
    }

    append ret [subst -nocommands {<tr>
      <td valign=top style="line-height:150%">
        <div style="white-space:wrap;font-size:larger" class=nounderline>
          <a href="$url">$s_title1 </a> 
          <div style="float:right;font-size:smaller;color:#BBB">($url)</div>
        </div>
          <div style="margin-left: 10ex; font:larger monospace">$s_apis</div>
        <div style="margin-left: 4ex; margin-bottom:1.5em">
           $s_content 
        </div>
      </td>
    }]
  }
  append ret { </table> }


  # If the query returned more than 10 results, add up to 10 links to 
  # each set of 10 results (first link to results 1-10, second to 11-20, 
  # third to 21-30, as required).
  #
  if {$nRes>10} {
    set s(0) {border:solid #044a64 1px;padding:1ex;margin:1ex;line-height:300%;}
    set s(1) "$s(0);background:#044a64;color:white"
    append ret <center><p>
    for {set i 0} {$i < 10 && ($i*10)<$nRes} {incr i} {
      append ret [subst {
        <a style="$s([expr {($iStart/10)==$i}])" 
           href="search?[cgi_encode_args [list q $::A(q) s $::A(s) i $i]]">[expr $i+1]</a>
      }]
    }
    append ret </center>
  }

  return $ret
}

proc main {} {
  global A
  cgi_parse_args

  # If "env=1" is specified, dump the environment variables instead
  # of running any search.
  if {[info exists ::A(env)]} { return [cgi_env_dump] }
  
  # If "admin=1" is specified, jump to the admin screen.
  if {[string match *admin* $::env(REQUEST_URI)]} {
    set ::PATH ../
    return [admin_list]
  }

  sqlite3 db search.d/search.db

  set cmd searchresults
  if {[info exists A(s)] && $A(s)=="c"} {
    set cmd searchchanges
  }

  db transaction {
    set t [ttime { 
      if {[catch $cmd srchout]} {
        set A(q) [string tolower $A(q)]
        set srchout [$cmd]
      }
      set doc $srchout
    }]
  }
  append doc "<center>"
  append doc "<p>Page generated by <a href='fts5.html'>FTS5</a> in about $t."
  append doc "</center>"
  return $doc

  # return [cgi_env_dump]
}

#=========================================================================

source [file dirname [info script]]/document_header.tcl

if {![info exists env(REQUEST_METHOD)]} {
  set env(REQUEST_METHOD) GET
  set env(QUERY_STRING) rebuild=1
  set ::HEADER ""

  #set env(QUERY_STRING) {q="one+two+three+four"+eleven}
  set env(QUERY_STRING) {q=windows}
  set ::HEADER ""
}

set ::PATH ""
if {0==[catch main res]} {
  set title "Search SQLite Documentation"
  if {[info exists ::A(q)]} {
    set initsearch [attrize $::A(q)]
    append title " - [htmlize $::A(q)]"
  } else {
    set initsearch {}
  }
  set document [document_header $title $::PATH $initsearch]
  if {$::A(s)!="d" && $::A(s)!="c"} {set ::A(s) d}
  append document [subst {
    <script>
      window.addEventListener('load', function() {
        var w = document.getElementById("searchmenu");
        w.style.display = "block";

        document.getElementById("searchtype").value = "$::A(s)"

        setTimeout(function(){
          var s = document.getElementById("searchbox");
          s.focus();
          s.select();
        }, 30);
      });
    </script>
  }]
  append document $res
} else {
  set document "<pre>"
  append document "Error: $res\n\n"
  append document $::errorInfo
  append document "</pre>"
}

puts "Content-type: text/html" 
puts "Content-Length: [string length $document]"
puts ""
puts $document
puts ""
flush stdout
close stdout

exit
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#!/usr/bin/tclsh.docsrc
#### Import of wapp.tcl
INCLUDE wapp.tcl
#### End of wapp.tcl

# Generate all header content for the output document
#
proc search_header {} {
  wapp-trim {
DOCHEAD {Search SQLite Documentation} {}
  }
}

#-------------------------------------------------------------------------
# Add an entry to the log database for the current query. Which 
# returns $nRes results.
#
proc search_add_log_entry {nRes} {
  if {[wapp-param-exists donotlog]} return
  sqlite3 db2 [file dir [wapp-param SCRIPT_FILENAME]]/search.d/searchlog.db
  db2 timeout 10000
  set ip [wapp-param REMOTE_ADDR]
  set query [wapp-param q]
  db2 eval {
    PRAGMA synchronous=OFF;
    PRAGMA journal_mode=OFF;
    BEGIN;
      CREATE TABLE IF NOT EXISTS log(
        ip,                  -- IP query was made from
        query,               -- Fts5 query string
        nres,                -- Number of results
        timestamp DEFAULT CURRENT_TIMESTAMP
      );
      INSERT INTO log(ip, query, nres) VALUES($ip, $query, $nRes);
    COMMIT;
  }
  db2 close
}

#-------------------------------------------------------------------------
# This command is similar to the builtin Tcl [time] command, except that
# it only ever runs the supplied script once. Also, instead of returning
# a string like "xxx microseconds per iteration", it returns "x.yy ms" or
# "x.yy s", depending on the magnitude of the time spent running the 
# command. For example:
#
#   % ttime {after 1500}
#   1.50 s
#   % ttime {after 45}
#   45.02 ms
#
proc ttime {script} {
  set t [lindex [time [list uplevel $script]] 0]
  if {$t>1000000} { return [format "%.2f s" [expr {$t/1000000.0}]] }
  return [format "%.2f ms" [expr {$t/1000.0}]]
}

#-----------------------------------------------------------------------
# Do a search of the change log
#
proc searchchanges {} {
  set q [wapp-param q]
  if {$q==""} {return {}}
  set open {<span style="background-color:#d9f2e6">}
  set close {</span>}
  set query {
    SELECT url, version, idx, highlight(change, 3, $open, $close) AS text 
    FROM change($q) ORDER BY rowid ASC
  }
  wapp-trim {
    <p>Change log entries mentioning: <b>%html($q)</b>
    <table border=0>
  }
  set s2 "style=\"margin-top:0\""
  set s1 "style=\"font-size:larger; text-align:left\" class=nounderline"
  set prev ""
  db eval $query {
    if {$prev!=$version} {
      wapp-trim {
        <tr> <td %unsafe($s1) valign=top> <a href='%url($url)'>%html($version)</a>
        <td> <ul %unsafe($s2)>
      }
      set prev $version
    }
    wapp-subst {<li value=%html($idx)> (%html($idx)) %unsafe($text)\n}
  }
  wapp-trim {
    </table>
    <center><p>You can also see the <a href=changes.html>entire
    changelog as a single page</a> if you wish.</center>
  }
}

#-----------------------------------------------------------------------
# Do a search over all documentation other than the change log
#
proc searchresults {} {
  set q [wapp-param q]
  if {$q==""} {return ""}

  # Count the '"' characters in $::A(q). If there is an odd number of
  # occurences, add a " to the end of the query so that fts5 can parse
  # it without error.
  if {[regexp -all \x22 $q] % 2} { append q \x22 }

  # Set iStart to the index of the first result to display. Results are
  # indexed starting at zero from most to least relevant.
  #
  set iStart 0
  catch {set iStart [expr {[wapp-param i 0]*10}]}

  # Grab a list of rowid results.
  #
  set sql {
    SELECT rowid FROM page WHERE page MATCH $q
    ORDER BY srank(page) DESC,
    rank * COALESCE(
      (SELECT percent FROM weight WHERE id=page.rowid), 100
    );
  }
  if {[catch { set lRowid [db eval $sql] }]} {
    set x ""
    foreach word [split $q " "] {
      append x " \"[string map [list "\"" "\"\""] $word]\""
    }
    set q [string trim $x]
    set lRowid [db eval $sql]
  }

  set lRes [list]
  foreach rowid $lRowid {
    if {$rowid > 1000} {
      set parent [expr $rowid / 1000]
      lappend subsections($parent) $rowid
    } else {
      lappend lRes $rowid
    }
  }

  set nRes [llength $lRes]
  set lRes [lrange $lRes $iStart [expr $iStart+9]]

  # Add an entry to the log database.
  #
  search_add_log_entry $nRes

  # If there are no results, return a message to that effect.
  #
  if {[llength $lRes] == 0} {
    wapp-subst {<p>No Results for: <b>%html($q)</b>\n}
  }
  
  # HTML markup used to highlight keywords within FTS5 generated snippets.
  #
  set open {<span style="background-color:#d9f2e6">}
  set close {</span>}
  set ellipsis {<b>&nbsp;...&nbsp;</b>}

  # Grab the required data
  #
  db eval [string map [list %LIST% [join $lRowid ,]] {
    SELECT 
      rowid AS parentid, 
      snippet(page, 0, $open, $close, $ellipsis, 6)  AS s_apis,
      snippet(page, 2, $open, $close, '', 40)        AS s_title1,
      snippet(page, 3, $open, $close, $ellipsis, 40) AS s_title2,
      snippet(page, 4, $open, $close, $ellipsis, 40) AS s_content,
      url, rank
    FROM page($q)
    WHERE rowid IN (%LIST%)
  }] X {
    foreach k [array names X] { set data($X(parentid),$k) [set X($k)] }
  }

  set i1 [expr {$iStart+1}]
  set i2 [expr {($nRes < $iStart+10) ? $nRes : $iStart+10}]
  wapp-trim {
    <table border=0>
    <p>Search results %html($i1)..%html($i2) of %html($nRes) for: <b>%html($q)</b>
  }

  foreach rowid $lRes {

    foreach a {parentid s_apis s_title1 s_content url rank} {
      set $a $data($rowid,$a)
    }

    if {[info exists subsections($parentid)]} {
      set childid [lindex $subsections($parentid) 0]
      set link $data($childid,url)
      set hdr $data($childid,s_title2)

      if {$hdr==""} {
        set s_content ""
      } else {
        set s_content [subst {
          <b><a style=color:#044a64 href=$link>$hdr</a></b>
        }]
      }

      append s_content " $data($childid,s_content)"
    }

    wapp-trim {<tr>
      <td valign=top style="line-height:150%">
        <div style="white-space:wrap;font-size:larger" class=nounderline>
          <a href="%url($url)">%unsafe($s_title1)</a> 
          <div style="float:right;font-size:smaller;color:#BBB">(%url($url))</div>
        </div>
          <div style="margin-left: 10ex; font:larger monospace">%unsafe($s_apis)</div>
        <div style="margin-left: 4ex; margin-bottom:1.5em">
           %unsafe($s_content)
        </div>
      </td>
    }
  }
  wapp-subst {</table>\n}


  # If the query returned more than 10 results, add up to 10 links to 
  # each set of 10 results (first link to results 1-10, second to 11-20, 
  # third to 21-30, as required).
  #
  if {$nRes>10} {
    set s(0) {border:solid #044a64 1px;padding:1ex;margin:1ex;line-height:300%;}
    set s(1) "$s(0);background:#044a64;color:white"
    wapp-subst {<center><p>\n}
    for {set i 0} {$i < 10 && ($i*10)<$nRes} {incr i} {
      set style $s([expr {($iStart/10)==$i}])
      wapp-trim {
        <a style="%html($style)"
           href="search?q=%qp($q)&i=%qp($i)">%html([expr $i+1])</a>
      }
    }
    wapp-subst {</center>\n}
  }
}

# This is the main entry point into the search result page generator
#
proc wapp-default {} {
  wapp-content-security-policy off
  wapp-allow-xorigin-params
  if {[wapp-param-exists env]} {
    search_header
    wapp-trim {
      <h1>Environment Dump For Debugging</h1>
      <pre>%html([wapp-debug-env])</pre>
    }
    return
  }

  # When running using the built-in webserver in Wapp (in other words,
  # when not running as CGI) any filename that contains a "." loads
  # directly from the filesystem.
  if {[string match *//127.0.0.1:* [wapp-param BASE_URL]]
   && [string match *.* [wapp-param PATH_INFO]]
  } {
    set altfile [file dir [wapp-param SCRIPT_FILENAME]][wapp-param PATH_INFO]
    set fd [open $altfile rb]
    fconfigure $fd -translation binary
    wapp-unsafe [read $fd]
    close $fd
    switch -glob -- $altfile {
      *.html {
        wapp-mimetype text/html
      }
      *.css {
        wapp-mimetype text/css
      }
      *.gif {
        wapp-mimetype image/gif
      }
    }
  }

  search_header
  sqlite3 db [file dir [wapp-param SCRIPT_FILENAME]]/search.d/search.db
  set searchType [wapp-param s d]
  if {$searchType=="c"} {
    set cmd searchchanges
  } else {
    set cmd searchresults
  }
  db transaction {
    set t [ttime {$cmd}]
  }
  wapp-trim {
    <center>
    <p>Page generated by <a href='fts5.html'>FTS5</a> in about %html($t).
    </center>
    <script>
      window.addEventListener('load', function() {
        var w = document.getElementById("searchmenu");
        w.style.display = "block";
        w = document.getElementById("searchtype");
        w.value = "%string($searchType)"
        setTimeout(function(){
          var s = document.getElementById("searchbox");
          s.value = "%string([wapp-param q])"
          s.focus();
          s.select();
        }, 30);
      });
    </script>
  }
}
wapp-start $argv

Deleted search/search4.tcl.

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#!/usr/bin/tclsqlite4

#=========================================================================
# Decode an HTTP %-encoded string
#
proc percent_decode {str} {
    # rewrite "+" back to space
    # protect \ and [ and ] by quoting with '\'
    set str [string map [list + { } "\\" "\\\\" \[ \\\[ \] \\\]] $str]

    # prepare to process all %-escapes
    regsub -all -- {%([A-Fa-f][A-Fa-f0-9])%([A-Fa-f89][A-Fa-f0-9])} \
        $str {[encoding convertfrom utf-8 [binary decode hex \1\2]]} str
    regsub -all -- {%([0-7][A-Fa-f0-9])} $str {\\u00\1} str

    # process %-escapes
    return [subst -novar $str]
}

#=========================================================================
# This proc is called to parse the arguments passed to this invocation of
# the CGI program (via either the GET or POST method). It returns a
# key/value list containing the arguments suitable for passing to [array
# set]. For example, if the CGI is invoked via a GET request on the URI:
#
#   http://www.sqlite.org/search?query=fts3+table&results=10
#
# then the returned list value is: 
#
#   {query {fts3 table} results 10}
#
proc cgi_parse_args {} {
  global env A

  if {$env(REQUEST_METHOD) == "GET"} {
    foreach q [split $env(QUERY_STRING) &] {
      if {[regexp {([a-z0-9]*)=(.*)} $q all var value]} {
        set A($var) [percent_decode $value]
      }
    }
  } elseif {$env(REQUEST_METHOD) == "POST"} {
    set qstring [read stdin $env(CONTENT_LENGTH)]
    foreach q [split $qstring &] {
      if {[regexp {([a-z0-9]*)=(.*)} $q all var value]} {
        set A($var) [percent_decode $value]
      }
    }
  } else {
    error "Unrecognized method: $env(REQUEST_METHOD)"
  }
}


#=========================================================================
# Redirect the web-browser to URL $url. This command does not return.
#
proc cgi_redirect {url} {
  set server $::env(SERVER_NAME)
  set path [file dirname $::env(REQUEST_URI)]
  if {[string range $path end end]!="/"} {
    append path /
  }

  puts "Status: 302 Redirect"
  puts "Location: http://${server}${path}${url}"
  puts "Content-Length: 0"
  puts ""
  exit
}

#=========================================================================
# The argument contains a key value list. The values in the list are
# transformed to an HTTP query key value list. For example:
#
#   % cgi_encode_args {s "search string" t "search \"type\""}
#   s=search+string&t=search+%22type%22
#
proc cgi_encode_args {list} {
  set reslist [list]
  foreach {key value} $list {
    set value [string map {
      \x20 +   \x21 %21 \x2A %2A \x22 %22 \x27 %27 \x28 %28 \x29 %29 \x3B %3B 
      \x3A %3A \x40 %40 \x26 %26 \x3D %3D \x2B %2B \x24 %24 \x2C %2C \x2F %2F 
      \x3F %3F \x25 %25 \x23 %23 \x5B %5B \x5D %5D
    } $value]

    lappend reslist "$key=$value"
  }
  join $reslist &
}

proc htmlize {str} { string map {< &lt; > &gt;} $str }
proc attrize {str} { string map {< &lt; > &gt; \x22 \x5c\x22} $str }

#=========================================================================

proc cgi_env_dump {} {

  set ret "<h1>Arguments</h1><table>"
  foreach {key value} [array get ::A] {
    append ret "<tr><td>[htmlize $key]<td>[htmlize $value]"
  }
  append ret "</table>"

  append ret "<h1>Environment</h1><table>"
  foreach {key value} [array get ::env] {
    append ret "<tr><td>[htmlize $key]<td>[htmlize $value]"
  }
  append ret "</table>"
  return $ret
}

proc searchform {} {
  return {}
  set initial "Enter search term:"
  catch { set initial $::A(q) }
  return [subst {
    <table style="margin: 1em auto"> <tr><td>Search SQLite docs for:<td>
      <form name=f method=GET action=search4>
        <input name=q type=text width=35 value="[attrize $initial]"></input>
        <input name=s type=submit value="Search"></input>
        <input name=s type=submit value="Lucky"></input>
      </form>
    </table>
    <script> 
      document.forms.f.q.focus()
      document.forms.f.q.select()
    </script>
  }]
}

proc footer {} {
  return {
    <hr>
    <table align=right>
    <td>
      <i>Powered by <a href="http://www.sqlite.org/src4">FTS5</a>.</i>
    </table>
  }
}


#-------------------------------------------------------------------------
# This command is similar to the builtin Tcl [time] command, except that
# it only ever runs the supplied script once. Also, instead of returning
# a string like "xxx microseconds per iteration", it returns "x.yy ms" or
# "x.yy s", depending on the magnitude of the time spent running the 
# command. For example:
#
#   % ttime {after 1500}
#   1.50 s
#   % ttime {after 45}
#   45.02 ms
#
proc ttime {script} {
  set t [lindex [time [list uplevel $script]] 0]
  if {$t>1000000} { return [format "%.2f s" [expr {$t/1000000.0}]] }
  return [format "%.2f ms" [expr {$t/1000.0}]]
}

proc rank {matchinfo args} {
  binary scan $matchinfo i* I

  set nPhrase [lindex $I 0]
  set nCol [lindex $I 1]

  set G [lrange $I 2 [expr {1+$nCol*$nPhrase}]]
  set L [lrange $I [expr {2+$nCol*$nPhrase}] end]

  foreach a $args { lappend log [expr {log10(100+$a)}] }

  set score 0.0
  set i 0
  foreach l $L g $G {
    if {$l > 0} {
      set div [lindex $log [expr $i%3]]
      set score [expr {$score + (double($l) / double($g)) / $div}]
    }
    incr i
  }

  return $score
}
proc erank {matchinfo args} {
  eval rank [list $matchinfo] $args
}


proc searchresults {} {
  if {![info exists ::A(q)]} return ""
  #set ::A(q) [string map {' ''} $A(q)]
  #regsub -all {[^-/"A-Za-z0-9]} $::A(q) { } ::A(q)

  # Count the '"' characters in $::A(q). If there is an odd number of
  # occurences, add a " to the end of the query so that fts3 can parse
  # it without error.
  if {[regexp -all \x22 $::A(q)] % 2} { append ::A(q) \x22 }

  set ::TITLE "Results for: \"[htmlize $::A(q)]\""

  #db func rank rank
  #db func erank erank

  set score 0
  catch {set score $::A(score)}

  # Set nRes to the total number of documents that the users query matches.
  # If nRes is 0, then the users query returned zero results. Return a short 
  # message to that effect.
  #
  set nRes [db one { SELECT count(*) FROM pagedata WHERE pagedata MATCH $::A(q) }]
  if {$nRes == 0} {
    return [subst { No results for: <b>[htmlize $::A(q)]</b> }]
  }

  # Set iStart to the index of the first result to display. Results are
  # indexed starting at zero from most to least relevant.
  #
  set iStart [expr {([info exists ::A(i)] ? $::A(i) : 0)*10}]

  # HTML markup used to highlight keywords within FTS3 generated snippets.
  #
  set open {<span style="font-weight:bold; color:navy">}
  set close {</span>}
  set ellipsis {<b>&nbsp;...&nbsp;</b>}

  set ret [subst {
    <table border=0>
    <p>Search results 
       [expr $iStart+1]..[expr {($nRes < $iStart+10) ? $nRes : $iStart+10}] 
       of $nRes for: <b>[htmlize $::A(q)]</b>
  }]

  set open {<span style="font-weight:bold; color:navy">}
  set close {</span>}
  set ellipsis {<b>&nbsp;...&nbsp;</b>}

  if {0==[info exists ::A(e)]} {
    set sqlquery {
      SELECT url, title, 
      snippet(pagedata, $open, $close, $ellipsis, 3, 40) AS snippet,
      '' AS report
      FROM pagedata WHERE pagedata MATCH $::A(q)
      ORDER BY rankc(pagedata, 1.0, 5.0, 10.0, 1.0) DESC
      LIMIT 10 OFFSET $iStart
    }
  } else {
    set sqlquery {
      SELECT url, title, 
      snippet(pagedata, $open, $close, $ellipsis, 3, 40) AS snippet,
      erankc(pagedata, 1.0, 5.0, 10.0, 1.0) AS report
      FROM pagedata WHERE pagedata MATCH $::A(q)
      ORDER BY rankc(pagedata, 1.0, 5.0, 10.0, 1.0) DESC
      LIMIT 10 OFFSET $iStart
    }
  }

  set resnum $iStart
  db eval $sqlquery {
    incr resnum

    append ret [subst -nocommands {<tr>
      <td valign=top>${resnum}.</td>
      <td valign=top>
        <div style="white-space:wrap">
          <a href="$url">$title</a>
        </div>
        <div style="font-size:small;margin-left: 2ex">
          <div style="width:80ex"> $snippet </div>
          <div style="margin-bottom:1em"><a href="$url">$url</a></div>
        </div>
      </td>

      <td width=100%>
      <td valign=top style="font-size:70%;white-space:nowrap;color:darkgreen"> $report </td>
    }]
  }
  append ret { </table> }


  # If the query returned more than 10 results, add up to 10 links to 
  # each set of 10 results (first link to results 1-10, second to 11-20, 
  # third to 21-30, as required).
  #
  if {$nRes>10} {
    set s(0) {border: solid #044a64 1px ; padding: 1ex ; margin: 1ex}
    set s(1) "$s(0);background:#044a64;color:white"
    append ret <center><p>
    for {set i 0} {$i < 10 && ($i*10)<$nRes} {incr i} {
      append ret [subst {
        <a style="$s([expr {($iStart/10)==$i}])" 
           href="search4?[cgi_encode_args [list q $::A(q) i $i]]">[expr $i+1]</a>
      }]
    }
    append ret </center>
  }

  return $ret
}

proc main {} {
  global A
  sqlite4 db search4.db
  cgi_parse_args

  db transaction {
    set t [ttime { set doc "[searchform] [searchresults] [footer]" }]
  }
  append doc "<p>Page generated in $t."
  return $doc

  # return [cgi_env_dump]
}

#=========================================================================

set ::HEADER {
  <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
  "http://www.w3.org/TR/html4/strict.dtd">
  <html><head>
  <title>$TITLE</title>
  <style type="text/css">
  body {
    margin: auto;
    font-family: Verdana, sans-serif;
    padding: 8px 1%;
  }

  a { color: #044a64 }
  a:visited { color: #734559 }

  .logo { position:absolute; margin:3px; }
  .tagline {
    float:right;
    text-align:right;
    font-style:italic;
    width:300px;
    margin:12px;
    margin-top:58px;
  }
  .menubar {
    clear: both;
    border-radius: 8px;
    background: #044a64;
    padding: 0px;
    margin: 0px;
    cell-spacing: 0px;
  }
  .toolbar {
    text-align: center;
    line-height: 1.6em;
    margin: 0;
    padding: 0px 8px;
  }
  .toolbar a { color: white;
  text-decoration: none; padding: 6px
  12px; }
  .toolbar a:visited { color: white; }
  .toolbar a:hover { color: #044a64;
  background: white; }

  .content    { margin: 5%; }
  .content dt { font-weight:bold; }
  .content dd { margin-bottom: 25px; margin-left:20%; }
  .content ul { padding:0px; padding-left: 15px; margin:0px; }
  </style>
  <meta http-equiv="content-type" content="text/html; charset=UTF-8">
    
  </head>
  <body>
  <div><!-- container div to satisfy validator -->

  <a href="index.html">
  <img class="logo" src="images/sqlite370_banner.gif" alt="SQLite Logo" border="0"></a>
    <div><!-- IE hack to prevent disappearing logo--></div>
    <div class="tagline">Small. Fast. Reliable.<br>Choose any three.</div>

    <table width=100% class="menubar"><tr><td>
  <table width=100% style="padding:0;margin:0;cell-spacing:0"><tr>
  <td width=100%>
  <div class="toolbar">
    <a href="about.html">About</a>
    <a href="sitemap.html">Sitemap</a>
    <a href="docs.html">Documentation</a>
    <a href="download.html">Download</a>
    <a href="copyright.html">License</a>
    <a href="news.html">News</a>
    <a href="support.html">Support</a>
  </div>
<td>
    <div style="padding:0 1em 0px 0;white-space:nowrap">
    <form name=f method="GET" action="search4">
      <input id=q name=q type=text value=""
       onfocus="entersearch()" onblur="leavesearch()" style="width:24ex;padding:1px 1ex; border:solid white 1px; font-size:0.9em">
      <input type=submit value="Go" style="border:solid white 1px;background-color:#044a64;color:white;font-size:0.9em;padding:0 1ex">
    </form>
    </div>
  </table>
</div></div></div></div>
</td></tr></table>
  
<script>
  gMsg = "Search SQLite Docs..."
  function entersearch() {
    var q = document.getElementById("q");
    if( q.value == gMsg ) { q.value = "" }
    q.style.color = "black"
    q.style.fontStyle = "normal"
  }
  function leavesearch() {
    var q = document.getElementById("q");
    if( q.value == "" ) { 
      q.value = gMsg
      q.style.color = "#044a64"
      q.style.fontStyle = "italic"
    }
  }
  function initsearch() {
    var q = document.getElementById("q");
    q.value = ""
      q.value = $::INITSEARCH
      q.style.color = "black"
      q.style.fontStyle = "normal"
  }
  window.onload = initsearch
</script>
}

if {![info exists env(REQUEST_METHOD)]} {
  set env(REQUEST_METHOD) GET
  set env(QUERY_STRING) rebuild=1
  set ::HEADER ""

  set env(QUERY_STRING) {q=cache+size}
  set ::HEADER ""
}


set TITLE "Search SQLite Documentation (fts5)"

if {0==[catch main res]} {
  if {[info exists ::A(q)]} {
    set ::INITSEARCH \"[attrize $::A(q)]\"
  } else {
    set ::INITSEARCH \"\"
  }
  set document [subst -nocommands $::HEADER]
  append document $res
} else {
  set document "<pre>"
  append document "Error: $res\n\n"
  append document $::errorInfo
  append document "</pre>"
}

puts "Content-type: text/html" 
puts "Content-Length: [string length $document]"
puts ""
puts $document
puts ""
flush stdout
close stdout

exit
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Added search/wapp.tcl.



























































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































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# Copyright (c) 2017 D. Richard Hipp
# 
# This program is free software; you can redistribute it and/or
# modify it under the terms of the Simplified BSD License (also
# known as the "2-Clause License" or "FreeBSD License".)
#
# This program 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.
#
#---------------------------------------------------------------------------
#
# Design rules:
#
#   (1)  All identifiers in the global namespace begin with "wapp"
#
#   (2)  Indentifiers intended for internal use only begin with "wappInt"
#

# Add text to the end of the HTTP reply.  No interpretation or transformation
# of the text is performs.  The argument should be enclosed within {...}
#
proc wapp {txt} {
  global wapp
  dict append wapp .reply $txt
}

# Add text to the page under construction.  Do no escaping on the text.
#
# Though "unsafe" in general, there are uses for this kind of thing.
# For example, if you want to return the complete, unmodified content of
# a file:
#
#         set fd [open content.html rb]
#         wapp-unsafe [read $fd]
#         close $fd
#
# You could do the same thing using ordinary "wapp" instead of "wapp-unsafe".
# The difference is that wapp-safety-check will complain about the misuse
# of "wapp", but it assumes that the person who write "wapp-unsafe" understands
# the risks.
#
# Though occasionally necessary, the use of this interface should be minimized.
#
proc wapp-unsafe {txt} {
  global wapp
  dict append wapp .reply $txt
}

# Add text to the end of the reply under construction.  The following
# substitutions are made:
#
#     %html(...)          Escape text for inclusion in HTML
#     %url(...)           Escape text for use as a URL
#     %qp(...)            Escape text for use as a URI query parameter
#     %string(...)        Escape text for use within a JSON string
#     %unsafe(...)        No transformations of the text
#
# The %unsafe substitution should be avoided whenever possible, obviously.
# In addition to the substitutions above, the text also does backslash
# escapes.
#
proc wapp-subst {txt} {
  global wapp
  regsub -all {%(html|url|qp|string|unsafe)\(([^)]+)\)} $txt \
         {[wappInt-enc-\1 "\2"]} txt
  dict append wapp .reply [uplevel 1 [list subst -novariables $txt]]
}

# There must be a wappInt-enc-NAME routine for each possible substitution
# in wapp-subst.  Thus there are routines for "html", "url", "qp", and "unsafe".
#
#    wappInt-enc-html           Escape text so that it is safe to use in the
#                               body of an HTML document.
#
#    wappInt-enc-url            Escape text so that it is safe to pass as an
#                               argument to href= and src= attributes in HTML.
#
#    wappInt-enc-qp             Escape text so that it is safe to use as the
#                               value of a query parameter in a URL or in
#                               post data or in a cookie.
#
#    wappInt-enc-string         Escape ", ', and \ for using inside of a
#                               javascript string literal.
#
#    wappInt-enc-unsafe         Perform no encoding at all.  Unsafe.
#
proc wappInt-enc-html {txt} {
  return [string map {& &amp; < &lt; > &gt;} $txt]
}
proc wappInt-enc-unsafe {txt} {
  return $txt
}
proc wappInt-enc-url {s} {
  if {[regsub -all {[^-{}@~?=#_.:/a-zA-Z0-9]} $s {[wappInt-%HHchar {&}]} s]} {
    set s [subst -novar -noback $s]
  }
  if {[regsub -all {[{}]} $s {[wappInt-%HHchar \\&]} s]} {
    set s [subst -novar -noback $s]
  }
  return $s
}
proc wappInt-enc-qp {s} {
  if {[regsub -all {[^-{}_.a-zA-Z0-9]} $s {[wappInt-%HHchar {&}]} s]} {
    set s [subst -novar -noback $s]
  }
  if {[regsub -all {[{}]} $s {[wappInt-%HHchar \\&]} s]} {
    set s [subst -novar -noback $s]
  }
  return $s
}
proc wappInt-enc-string {s} {
  return [string map {\\ \\\\ \" \\\" ' \\'} $s]
}

# Works like wapp-subst, but also removes whitespace from the beginning
# of lines.
#
proc wapp-trim {txt} {
  global wapp
  regsub -all {\n\s+} [string trim $txt] \n txt
  regsub -all {%(html|url|qp|string|unsafe)\(([^)]+)\)} $txt \
         {[wappInt-enc-\1 "\2"]} txt
  dict append wapp .reply [uplevel 1 [list subst -novariables $txt]]
}

# This is a helper routine for wappInt-enc-url and wappInt-enc-qp.  It returns
# an appropriate %HH encoding for the single character c.  If c is a unicode
# character, then this routine might return multiple bytes:  %HH%HH%HH
#
proc wappInt-%HHchar {c} {
  if {$c==" "} {return +}
  return [regsub -all .. [binary encode hex [encoding convertto utf-8 $c]] {%&}]
}


# Undo the www-url-encoded format.
#
# HT: This code stolen from ncgi.tcl
#
proc wappInt-decode-url {str} {
  set str [string map [list + { } "\\" "\\\\" \[ \\\[ \] \\\]] $str]
  regsub -all -- \
      {%([Ee][A-Fa-f0-9])%([89ABab][A-Fa-f0-9])%([89ABab][A-Fa-f0-9])} \
      $str {[encoding convertfrom utf-8 [binary decode hex \1\2\3]]} str
  regsub -all -- \
      {%([CDcd][A-Fa-f0-9])%([89ABab][A-Fa-f0-9])}                     \
      $str {[encoding convertfrom utf-8 [binary decode hex \1\2]]} str
  regsub -all -- {%([0-7][A-Fa-f0-9])} $str {\\u00\1} str
  return [subst -novar $str]
}

# Reset the document back to an empty string.
#
proc wapp-reset {} {
  global wapp
  dict set wapp .reply {}
}

# Change the mime-type of the result document.
#
proc wapp-mimetype {x} {
  global wapp
  dict set wapp .mimetype $x
}

# Change the reply code.
#
proc wapp-reply-code {x} {
  global wapp
  dict set wapp .reply-code $x
}

# Set a cookie
#
proc wapp-set-cookie {name value} {
  global wapp
  dict lappend wapp .new-cookies $name $value
}

# Unset a cookie
#
proc wapp-clear-cookie {name} {
  wapp-set-cookie $name {}
}

# Add extra entries to the reply header
#
proc wapp-reply-extra {name value} {
  global wapp
  dict lappend wapp .reply-extra $name $value
}

# Specifies how the web-page under construction should be cached.
# The argument should be one of:
#
#    no-cache
#    max-age=N             (for some integer number of seconds, N)
#    private,max-age=N
#
proc wapp-cache-control {x} {
  wapp-reply-extra Cache-Control $x
}

# Redirect to a different web page
#
proc wapp-redirect {uri} {
  wapp-reply-code {307 Redirect}
  wapp-reply-extra Location $uri
}

# Return the value of a wapp parameter
#
proc wapp-param {name {dflt {}}} {
  global wapp
  if {![dict exists $wapp $name]} {return $dflt}
  return [dict get $wapp $name]
}

# Return true if a and only if the wapp parameter $name exists
#
proc wapp-param-exists {name} {
  global wapp
  return [dict exists $wapp $name]
}

# Set the value of a wapp parameter
#
proc wapp-set-param {name value} {
  global wapp
  dict set wapp $name $value
}

# Return all parameter names that match the GLOB pattern, or all
# names if the GLOB pattern is omitted.
#
proc wapp-param-list {{glob {*}}} {
  global wapp
  return [dict keys $wapp $glob]
}

# By default, Wapp does not decode query parameters and POST parameters
# for cross-origin requests.  This is a security restriction, designed to
# help prevent cross-site request forgery (CSRF) attacks.
#
# As a consequence of this restriction, URLs for sites generated by Wapp
# that contain query parameters will not work as URLs found in other
# websites.  You cannot create a link from a second website into a Wapp
# website if the link contains query planner, by default.
#
# Of course, it is sometimes desirable to allow query parameters on external
# links.  For URLs for which this is safe, the application should invoke
# wapp-allow-xorigin-params.  This procedure tells Wapp that it is safe to
# go ahead and decode the query parameters even for cross-site requests.
#
# In other words, for Wapp security is the default setting.  Individual pages
# need to actively disable the cross-site request security if those pages
# are safe for cross-site access.
#
proc wapp-allow-xorigin-params {} {
  global wapp
  if {![dict exists $wapp .qp] && ![dict get $wapp SAME_ORIGIN]} {
    wappInt-decode-query-params
  }
}

# Set the content-security-policy.
#
# The default content-security-policy is very strict:  "default-src 'self'"
# The default policy prohibits the use of in-line javascript or CSS.
#
# Provide an alternative CSP as the argument.  Or use "off" to disable
# the CSP completely.
#
proc wapp-content-security-policy {val} {
  global wapp
  if {$val=="off"} {
    dict unset wapp .csp
  } else {
    dict set wapp .csp $val
  }
}

# Examine the bodys of all procedures in this program looking for
# unsafe calls to various Wapp interfaces.  Return a text string
# containing warnings. Return an empty string if all is ok.
#
# This routine is advisory only.  It misses some constructs that are
# dangerous and flags others that are safe.
#
proc wapp-safety-check {} {
  set res {}
  foreach p [info procs] {
    set ln 0
    foreach x [split [info body $p] \n] {
      incr ln
      if {[regexp {^[ \t]*wapp[ \t]+([^\n]+)} $x all tail]
       && [string index $tail 0]!="\173"
       && [regexp {[[$]} $tail]
      } {
        append res "$p:$ln: unsafe \"wapp\" call: \"[string trim $x]\"\n"
      }
      if {[regexp {^[ \t]*wapp-(subst|trim)[ \t]+[^\173]} $x all cx]} {
        append res "$p:$ln: unsafe \"wapp-$cx\" call: \"[string trim $x]\"\n"
      }
    }
  }
  return $res
}

# Return a string that descripts the current environment.  Applications
# might find this useful for debugging.
#
proc wapp-debug-env {} {
  global wapp
  set out {}
  foreach var [lsort [dict keys $wapp]] {
    if {[string index $var 0]=="."} continue
    append out "$var = [list [dict get $wapp $var]]\n"
  }
  return $out
}

# Start up the wapp framework.  Parameters are a list passed as the
# single argument.
#
#    -server $PORT         Listen for HTTP requests on this TCP port $PORT
#
#    -scgi $PORT           Listen for SCGI requests on TCP port $PORT
#
#    -cgi                  Handle a single CGI request
#
# With no arguments, the behavior is called "auto".  In "auto" mode,
# if the GATEWAY_INTERFACE environment variable indicates CGI, then run
# as CGI.  Otherwise, start an HTTP server bound to the loopback address
# only, on an arbitrary TCP port, and automatically launch a web browser
# on that TCP port.
#
# Additional options:
#
#    -trace               "puts" each request URL as it is handled, for
#                         debugging
#
#    -lint                Run wapp-safety-check on the application instead
#                         of running the application itself
#
#    -Dvar=value          Set TCL global variable "var" to "value"
#
#
proc wapp-start {arglist} {
  global env
  set mode auto
  set port 0
  set n [llength $arglist]
  for {set i 0} {$i<$n} {incr i} {
    set term [lindex $arglist $i]
    if {[string match --* $term]} {set term [string range $term 1 end]}
    switch -glob -- $term {
      -server {
        incr i;
        set mode "server"
        set port [lindex $arglist $i]
      }
      -scgi {
        incr i;
        set mode "scgi"
        set port [lindex $arglist $i]
      }
      -cgi {
        set mode "cgi"
      }
      -trace {
        proc wappInt-trace {} {
          set q [wapp-param QUERY_STRING]
          set uri [wapp-param BASE_URL][wapp-param PATH_INFO]
          if {$q!=""} {append uri ?$q}
          puts $uri
        }
      }
      -lint {
        set res [wapp-safety-check]
        if {$res!=""} {
          puts "Potential problems in this code:"
          puts $res
          exit 1
        } else {
          exit
        }
      }
      -D*=* {
        if {[regexp {^.D([^=]+)=(.*)$} $term all var val]} {
          set ::$var $val
        }
      }
      default {
        error "unknown option: $term"
      }
    }
  }
  if {($mode=="auto"
       && [info exists env(GATEWAY_INTERFACE)]
       && $env(GATEWAY_INTERFACE)=="CGI/1.0")
    || $mode=="cgi"
  } {
    wappInt-handle-cgi-request
    return
  }
  if {$mode=="scgi"} {
    wappInt-start-listener $port 1 0 1
  } elseif {$mode=="server"} {
    wappInt-start-listener $port 0 0 0
  } else {
    wappInt-start-listener $port 1 1 0
  }
  vwait ::forever
}

# Tracing function for each HTTP request.  This is overridden by wapp-start
# if tracing is enabled.
#
proc wappInt-trace {} {}

# Start up a listening socket.  Arrange to invoke wappInt-new-connection
# for each inbound HTTP connection.
#
#    localonly   -   If true, listen on 127.0.0.1 only
#
#    browser     -   If true, launch a web browser pointing to the new server
#
proc wappInt-start-listener {port localonly browser scgi} {
  if {$scgi} {
    set type SCGI
    set server [list wappInt-new-connection wappInt-scgi-readable]
  } else {
    set type HTTP
    set server [list wappInt-new-connection wappInt-http-readable]
  }
  if {$localonly} {
    set x [socket -server $server -myaddr 127.0.0.1 $port]
  } else {
    set x [socket -server $server $port]
  }
  set coninfo [chan configure $x -sockname]
  set port [lindex $coninfo 2]
  if {$browser} {
    wappInt-start-browser http://127.0.0.1:$port/
  } else {
    puts "Listening for $type requests on TCP port $port"
  }
}

# Start a web-browser and point it at $URL
#
proc wappInt-start-browser {url} {
  global tcl_platform
  if {$tcl_platform(platform)=="windows"} {
    exec cmd /c start $url &
  } elseif {$tcl_platform(os)=="Darwin"} {
    exec open $url &
  } elseif {[catch {exec xdg-open $url}]} {
    exec firefox $url &
  }
}

# Accept a new inbound HTTP request
#
proc wappInt-new-connection {callback chan ip port} {
  upvar #0 wappInt-$chan W
  set W [dict create REMOTE_ADDR $ip REMOTE_PORT $port .header {}]
  fconfigure $chan -blocking 0 -translation binary
  fileevent $chan readable [list $callback $chan]
}

# Close an input channel
#
proc wappInt-close-channel {chan} {
  if {$chan=="stdout"} {
    # This happens after completing a CGI request
    exit 0
  } else {
    unset ::wappInt-$chan
    close $chan
  }
}

# Process new text received on an inbound HTTP request
#
proc wappInt-http-readable {chan} {
  if {[catch [list wappInt-http-readable-unsafe $chan] msg]} {
    puts stderr "$msg\n$::errorInfo"
    wappInt-close-channel $chan
  }
}
proc wappInt-http-readable-unsafe {chan} {
  upvar #0 wappInt-$chan W wapp wapp
  if {![dict exists $W .toread]} {
    # If the .toread key is not set, that means we are still reading
    # the header
    set line [string trimright [gets $chan]]
    set n [string length $line]
    if {$n>0} {
      if {[dict get $W .header]=="" || [regexp {^\s+} $line]} {
        dict append W .header $line
      } else {
        dict append W .header \n$line
      }
      if {[string length [dict get $W .header]]>100000} {
        error "HTTP request header too big - possible DOS attack"
      }
    } elseif {$n==0} {
      # We have reached the blank line that terminates the header.
      global argv0
      dict set W SCRIPT_FILENAME $argv0
      dict set W DOCUMENT_ROOT [file dir $argv0]
      if {[wappInt-parse-header $chan]} {
        catch {close $chan}
        return
      }
      set len 0
      if {[dict exists $W CONTENT_LENGTH]} {
        set len [dict get $W CONTENT_LENGTH]
      }
      if {$len>0} {
        # Still need to read the query content
        dict set W .toread $len
      } else {
        # There is no query content, so handle the request immediately
        set wapp $W
        wappInt-handle-request $chan 0
      }
    }
  } else {
    # If .toread is set, that means we are reading the query content.
    # Continue reading until .toread reaches zero.
    set got [read $chan [dict get $W .toread]]
    dict append W CONTENT $got
    dict set W .toread [expr {[dict get $W .toread]-[string length $got]}]
    if {[dict get $W .toread]<=0} {
      # Handle the request as soon as all the query content is received
      set wapp $W
      wappInt-handle-request $chan 0
    }
  }
}

# Decode the HTTP request header.
#
# This routine is always running inside of a [catch], so if
# any problems arise, simply raise an error.
#
proc wappInt-parse-header {chan} {
  upvar #0 wappInt-$chan W
  set hdr [split [dict get $W .header] \n]
  if {$hdr==""} {return 1}
  set req [lindex $hdr 0]
  dict set W REQUEST_METHOD [set method [lindex $req 0]]
  if {[lsearch {GET HEAD POST} $method]<0} {
    error "unsupported request method: \"[dict get $W REQUEST_METHOD]\""
  }
  set uri [lindex $req 1]
  set split_uri [split $uri ?]
  set uri0 [lindex $split_uri 0]
  if {![regexp {^/[-.a-z0-9_/]*$} $uri0]} {
    error "invalid request uri: \"$uri0\""
  }
  dict set W REQUEST_URI $uri0
  dict set W PATH_INFO $uri0
  set uri1 [lindex $split_uri 1]
  dict set W QUERY_STRING $uri1
  set n [llength $hdr]
  for {set i 1} {$i<$n} {incr i} {
    set x [lindex $hdr $i]
    if {![regexp {^(.+): +(.*)$} $x all name value]} {
      error "invalid header line: \"$x\""
    }
    set name [string toupper $name]
    switch -- $name {
      REFERER {set name HTTP_REFERER}
      USER-AGENT {set name HTTP_USER_AGENT}
      CONTENT-LENGTH {set name CONTENT_LENGTH}
      CONTENT-TYPE {set name CONTENT_TYPE}
      HOST {set name HTTP_HOST}
      COOKIE {set name HTTP_COOKIE}
      ACCEPT-ENCODING {set name HTTP_ACCEPT_ENCODING}
      default {set name .hdr:$name}
    }
    dict set W $name $value
  }
  return 0
}

# Decode the QUERY_STRING parameters from a GET request or the
# application/x-www-form-urlencoded CONTENT from a POST request.
#
# This routine sets the ".qp" element of the ::wapp dict as a signal
# that query parameters have already been decoded.
#
proc wappInt-decode-query-params {} {
  global wapp
  dict set wapp .qp 1
  if {[dict exists $wapp QUERY_STRING]} {
    foreach qterm [split [dict get $wapp QUERY_STRING] &] {
      set qsplit [split $qterm =]
      set nm [lindex $qsplit 0]
      if {[regexp {^[a-z][a-z0-9]*$} $nm]} {
        dict set wapp $nm [wappInt-decode-url [lindex $qsplit 1]]
      }
    }
  }
  if {[dict exists $wapp CONTENT_TYPE]
   && [dict get $wapp CONTENT_TYPE]=="application/x-www-form-urlencoded"
   && [dict exists $wapp CONTENT]
  } {
    foreach qterm [split [string trim [dict get $wapp CONTENT]] &] {
      set qsplit [split $qterm =]
      set nm [lindex $qsplit 0]
      if {[regexp {^[a-z][-a-z0-9_]*$} $nm]} {
        dict set wapp $nm [wappInt-decode-url [lindex $qsplit 1]]
      }
    }
  }
  # To-Do:  Perhaps add support for multipart/form-data decoding.
  # Alternatively, perhaps multipart/form-data decoding can be done
  # by application code using a separate helper function, like
  # "wapp_decode_multipart_formdata" or somesuch.
}

# Invoke application-supplied methods to generate a reply to
# a single HTTP request.
#
# This routine always runs within [catch], so handle exceptions by
# invoking [error].
#
proc wappInt-handle-request {chan useCgi} {
  global wapp
  dict set wapp .reply {}
  dict set wapp .mimetype {text/html; charset=utf-8}
  dict set wapp .reply-code {200 Ok}
  dict set wapp .csp {default-src 'self'}

  # Set up additional CGI environment values
  #
  if {![dict exists $wapp HTTP_HOST]} {
    dict set wapp BASE_URL {}
  } elseif {[dict exists $wapp HTTPS]} {
    dict set wapp BASE_URL https://[dict get $wapp HTTP_HOST]
  } else {
    dict set wapp BASE_URL http://[dict get $wapp HTTP_HOST]
  }
  if {![dict exists $wapp REQUEST_URI]} {
    dict set wapp REQUEST_URI /
  } elseif {[regsub {\?.*} [dict get $wapp REQUEST_URI] {} newR]} {
    # Some servers (ex: nginx) append the query parameters to REQUEST_URI.
    # These need to be stripped off
    dict set wapp REQUEST_URI $newR
  }
  if {[dict exists $wapp SCRIPT_NAME]} {
    dict append wapp BASE_URL [dict get $wapp SCRIPT_NAME]
  } else {
    dict set wapp SCRIPT_NAME {}
  }
  if {![dict exists $wapp PATH_INFO]} {
    # If PATH_INFO is missing (ex: nginx) the construct it
    set URI [dict get $wapp REQUEST_URI]
    set skip [string length [dict get $wapp SCRIPT_NAME]]
    dict set wapp PATH_INFO [string range $URI $skip end]
  }
  if {[regexp {^/([^/]+)(.*)$} [dict get $wapp PATH_INFO] all head tail]} {
    dict set wapp PATH_HEAD $head
    dict set wapp PATH_TAIL [string trimleft $tail /]
  } else {
    dict set wapp PATH_INFO {}
    dict set wapp PATH_HEAD {}
    dict set wapp PATH_TAIL {}
  }
  dict set wapp SELF_URL [dict get $wapp BASE_URL]/[dict get $wapp PATH_HEAD]

  # Parse query parameters from the query string, the cookies, and
  # POST data
  #
  if {[dict exists $wapp HTTP_COOKIE]} {
    foreach qterm [split [dict get $wapp HTTP_COOKIE] {;}] {
      set qsplit [split [string trim $qterm] =]
      set nm [lindex $qsplit 0]
      if {[regexp {^[a-z][-a-z0-9_]*$} $nm]} {
        dict set wapp $nm [wappInt-decode-url [lindex $qsplit 1]]
      }
    }
  }
  if {[dict exists $wapp HTTP_REFERER]
   && [string match [dict get $wapp BASE_URL]/* [dict get $wapp HTTP_REFERER]]
  } {
    set same_origin 1
  } else {
    set same_origin 0
  }
  dict set wapp SAME_ORIGIN $same_origin
  if {$same_origin} {
    wappInt-decode-query-params
  }

  # Invoke the application-defined handler procedure for this page
  # request.  If an error occurs while running that procedure, generate
  # an HTTP reply that contains the error message.
  #
  wapp-before-dispatch-hook
  wappInt-trace
  set mname [dict get $wapp PATH_HEAD]
  if {[catch {
    if {$mname!="" && [llength [info proc wapp-page-$mname]]>0} {
      wapp-page-$mname
    } else {
      wapp-default
    }
  } msg]} {
    wapp-reset
    wapp-reply-code "500 Internal Server Error"
    wapp-mimetype text/html
    wapp-trim {
      <h1>Wapp Application Error</h1>
      <pre>%html($::errorInfo)</pre>
    }
    dict unset wapp .new-cookies
  }

  # Transmit the HTTP reply
  #
  if {$chan=="stdout"} {
    puts $chan "Status: [dict get $wapp .reply-code]\r"
  } else {
    puts $chan "HTTP/1.1 [dict get $wapp .reply-code]\r"
    puts $chan "Server: wapp\r"
    puts $chan "Connection: close\r"
  }
  if {[dict exists $wapp .reply-extra]} {
    foreach {name value} [dict get $wapp .reply-extra] {
      puts $chan "$name: $value\r"
    }
  }
  if {[dict exists $wapp .csp]} {
    puts $chan "Content-Security-Policy: [dict get $wapp .csp]\r"
  }
  set mimetype [dict get $wapp .mimetype]
  puts $chan "Content-Type: $mimetype\r"
  if {[dict exists $wapp .new-cookies]} {
    foreach {nm val} [dict get $wapp .new-cookies] {
      if {[regexp {^[a-z][-a-z0-9_]*$} $nm]} {
        if {$val==""} {
          puts $chan "Set-Cookie: $nm=; HttpOnly; Path=/; Max-Age=1\r"
        } else {
          set val [wappInt-enc-url $val]
          puts $chan "Set-Cookie: $nm=$val; HttpOnly; Path=/\r"
        }
      }
    }
  }
  if {[string match text/* $mimetype]} {
    set reply [encoding convertto utf-8 [dict get $wapp .reply]]
    if {[regexp {\ygzip\y} [wapp-param HTTP_ACCEPT_ENCODING]]} {
      catch {
        set x [zlib gzip $reply]
        set reply $x
        puts $chan "Content-Encoding: gzip\r"
      }
    }
  } else {
    set reply [dict get $wapp .reply]
  }
  puts $chan "Content-Length: [string length $reply]\r"
  puts $chan \r
  puts $chan $reply
  flush $chan
  wappInt-close-channel $chan
}

# This routine runs just prior to request-handler dispatch.  The
# default implementation is a no-op, but applications can override
# to do additional transformations or checks.
#
proc wapp-before-dispatch-hook {} {return}

# Process a single CGI request
#
proc wappInt-handle-cgi-request {} {
  global wapp env
  foreach key {
    CONTENT_LENGTH
    CONTENT_TYPE
    DOCUMENT_ROOT
    HTTP_ACCEPT_ENCODING
    HTTP_COOKIE
    HTTP_HOST
    HTTP_REFERER
    HTTP_USER_AGENT
    HTTPS
    PATH_INFO
    QUERY_STRING
    REMOTE_ADDR
    REQUEST_METHOD
    REQUEST_URI
    REMOTE_USER
    SCRIPT_FILENAME
    SCRIPT_NAME
    SERVER_NAME
    SERVER_PORT
    SERVER_PROTOCOL
  } {
    if {[info exists env($key)]} {
      dict set wapp $key $env($key)
    }
  }
  set len 0
  if {[dict exists $wapp CONTENT_LENGTH]} {
    set len [dict get $wapp CONTENT_LENGTH]
  }
  if {$len>0} {
    fconfigure stdin -translation binary
    dict set wapp CONTENT [read stdin $len]
  }
  fconfigure stdout -translation binary
  wappInt-handle-request stdout 1
}

# Process new text received on an inbound SCGI request
#
proc wappInt-scgi-readable {chan} {
  if {[catch [list wappInt-scgi-readable-unsafe $chan] msg]} {
    puts stderr "$msg\n$::errorInfo"
    wappInt-close-channel $chan
  }
}
proc wappInt-scgi-readable-unsafe {chan} {
  upvar #0 wappInt-$chan W wapp wapp
  if {![dict exists $W .toread]} {
    # If the .toread key is not set, that means we are still reading
    # the header.
    #
    # An SGI header is short.  This implementation assumes the entire
    # header is available all at once.
    #
    set req [read $chan 15]
    set n [string length $req]
    scan $req %d:%s len hdr
    incr len [string length "$len:,"]
    append hdr [read $chan [expr {$len-15}]]
    foreach {nm val} [split $hdr \000] {
      if {$nm==","} break
      dict set W $nm $val
    }
    set len 0
    if {[dict exists $W CONTENT_LENGTH]} {
      set len [dict get $W CONTENT_LENGTH]
    }
    if {$len>0} {
      # Still need to read the query content
      dict set W .toread $len
    } else {
      # There is no query content, so handle the request immediately
      set wapp $W
      wappInt-handle-request $chan 0
    }
  } else {
    # If .toread is set, that means we are reading the query content.
    # Continue reading until .toread reaches zero.
    set got [read $chan [dict get $W .toread]]
    dict append W CONTENT $got
    dict set W .toread [expr {[dict get $W .toread]-[string length $got]}]
    if {[dict get $W .toread]<=0} {
      # Handle the request as soon as all the query content is received
      set wapp $W
      wappInt-handle-request $chan 0
    }
  }
}

# Call this version 1.0
package provide wapp 1.0