Marc-Andre Lemburg <mal@lemburg.com>:

Generator for the new ucnhash module (ucnhash.h|c). Uses perfect_hash.py
to create the ucnhash module.

Tools/perfecthash/GenUCNHash.py

+#! /usr/bin/env python
+import sys
+import string
+import perfect_hash
+
+# This is a user of perfect_hash.py
+# that takes as input the UnicodeData.txt file available from:
+# ftp://ftp.unicode.org/Public/UNIDATA/UnicodeData.txt
+
+# It generates a hash table from Unicode Character Name ->
+# unicode code space value.
+
+# These variables determine which hash function is tried first.
+# Yields a multiple of 1.7875 for UnicodeData.txt on 2000/06/24/
+f1Seed = 1694245428
+f2Seed = -1917331657
+
+# Maximum allowed multipler, if this isn't None then instead of continually
+# increasing C, it resets it back to initC to keep searching for
+# a solution.
+minC = 1.7875
+# Initial multiplier for trying to find a perfect hash function.
+initC = 1.7875
+
+moduleName = "ucnhash"
+dataArrayName = "aucn"
+dataArrayType = "_Py_UnicodeCharacterName"
+headerFileName = "ucnhash.h"
+cFileName      = "ucnhash.c"
+structName     = "_Py_UCNHashAPI"
+
+keys = []
+hashData = {}
+
+def generateOutputFiles(perfHash, hashData):
+  header = perfHash.generate_header(structName)
+  header = header + """
+typedef struct 
+{
+    const char *pszUCN;
+    unsigned int uiValue;
+} _Py_UnicodeCharacterName;
+
+"""
+  
+  code = perfHash.generate_code(moduleName,
+                                dataArrayName,
+                                dataArrayType,
+                                structName)
+  out = open(headerFileName, "w")
+  out.write(header)
+  out = open(cFileName, "w")
+  out.write("#include <%s>\n" % headerFileName)
+  out.write(code)
+  perfHash.generate_graph(out)
+  out.write("""
+  
+static const _Py_UnicodeCharacterName aucn[] = 
+{
+""")
+  for i in xrange(len(keys)):
+    v = hashData[keys[i][0]]
+    out.write('  { "' + keys[i][0] + '", ' + hex(v) + " }," + "\n")
+  out.write("};\n\n")
+  sys.stderr.write('\nGenerated output files: \n')
+  sys.stderr.write('%s\n%s\n' % (headerFileName, cFileName))
+
+def main():
+  # Suck in UnicodeData.txt and spit out the generated files.
+  input = open(sys.argv[1], 'r')
+  i = 0
+  while 1:
+    line = input.readline()
+    if line == "": break
+    fields = string.split(line, ';')
+    if len(fields) < 2:
+      sys.stderr.write('Ill-formated line!\n')
+      sys.stderr.write('line #: %d\n' % (i + 1))
+      sys.exit()
+    data, key = fields[:2]
+    key = string.strip( key )
+    # Any name starting with '<' is a control, or start/end character,
+    # so skip it...
+    if key[0] == "<":
+      continue
+    hashcode = i
+    i = i + 1
+    # force the name to uppercase
+    keys.append( (string.upper(key),hashcode) )
+    data = string.atoi(data, 16)
+    hashData[key] = data
+
+  input.close()
+  sys.stderr.write('%i key/hash pairs read\n' % len(keys) )
+  perfHash = perfect_hash.generate_hash(keys, 1,
+                                        minC, initC,
+                                        f1Seed, f2Seed,
+                                        # increment, tries
+                                        0.0025, 50)
+  generateOutputFiles(perfHash, hashData)
+
+if __name__ == '__main__':
+  if len(sys.argv) == 1:
+    sys.stdout = sys.stderr
+    print 'Usage: %s <input filename>' % sys.argv[0]
+    print '  The input file needs to be UnicodeData.txt'
+    sys.exit()
+  main()
+