#! /usr/bin/env tclsh
if {[llength $argv] != 1} {
puts stderr "Usage: generate-mime-type <file>"
exit 1
}
set mimeinfofile [lindex $argv 0]
set modulus 16777259
# Must match what is in filed.c
proc filed_hash {str mod} {
set retval [expr {$mod - 1}]
set prev [expr {$mod % 255}]
for {set idx 0} {$idx < [string length $str]} {incr idx} {
set curr [string index $str $idx]
binary scan $curr H* curr
set curr [format %u 0x$curr]
if {$curr < 32} {
set curr [expr {255 - $curr}]
} else {
set curr [expr {$curr - 32}]
}
if {$prev < $curr} {
set diff [expr {$curr - $prev}]
} else {
set diff [expr {$prev - $curr}]
}
set prev $curr
set retval [expr {($retval << 3) & 0xffffffff}]
set retval [expr {$retval ^ $diff}]
}
set retval [expr {$retval % $mod}]
return $retval
}
# Read contents of mime types file
set fd [open $mimeinfofile]
set mimeinfo [read $fd]
close $fd
# Parse into type and extensions pairs
foreach line [split $mimeinfo "\n"] {
regsub {#.*} $line {} line
set line [string trim $line]
if {$line == ""} {
continue
}
set line [split $line]
set mime [lindex $line 0]
set extensions [lrange $line 1 end]
foreach extension $extensions {
if {$extension == ""} {
continue
}
set extensioninfo($extension) $mime
}
}
# For every extension, generate a hash
# For every hash, note the extension
foreach extension [array names extensioninfo] {
set hash_id [filed_hash $extension $modulus]
lappend hashinfo($hash_id) $extension
}
# Emit a C fragment to take a pointer (p) to an extension determine the mime type
puts "\tswitch (filed_hash((const unsigned char *) p, $modulus)) \{"
foreach hash [lsort -integer -increasing [array names hashinfo]] {
puts "\t\tcase $hash:"
foreach extension $hashinfo($hash) {
puts "\t\t\tif (strcmp(p, \"$extension\") == 0) \{"
puts "\t\t\t\treturn(\"$extensioninfo($extension)\");"
puts "\t\t\t\}"
}
puts "\t\t\treturn(FILED_DEFAULT_TYPE);"
}
puts "\t\}"
# Declare victory
exit 0