michael@0: #!/usr/bin/env python
michael@0: 
michael@0: # This Source Code Form is subject to the terms of the Mozilla Public
michael@0: # License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0: # file, You can obtain one at http://mozilla.org/MPL/2.0/.
michael@0: 
michael@0: # This script generates nsStyleStructList.h, which contains macro invocations
michael@0: # that can be used for three things:
michael@0: #
michael@0: # 1. To generate code for each inherited style struct.
michael@0: # 2. To generate code for each reset style struct.
michael@0: # 3. To generate a tree of nested if statements that can be used to run
michael@0: #    some code on each style struct.
michael@0: #
michael@0: # As an example, if we assume that we have only four style structs, the
michael@0: # generated tree of nested if statements looks like this:
michael@0: #
michael@0: #   if (STYLE_STRUCT_TEST < 4) {
michael@0: #     if (STYLE_STRUCT_TEST < 2) {
michael@0: #       if (STYLE_STRUCT_TEST == 0) {
michael@0: #         ... code for style struct with id 0 ...
michael@0: #       } else {
michael@0: #         ... code for style struct with id 1 ...
michael@0: #       }
michael@0: #     } else {
michael@0: #       if (STYLE_STRUCT_TEST == 2) {
michael@0: #         ... code for style struct with id 2 ...
michael@0: #       } else {
michael@0: #         ... code for style struct with id 3 ...
michael@0: #       }
michael@0: #     }
michael@0: #   }
michael@0: #
michael@0: # The TOPLEVELBRANCHES variable controls how widely we branch on the outermost
michael@0: # if statement.  In the example above, it splits the search space in 2, but with
michael@0: # a larger number of style structs to test -- particularly when the number is
michael@0: # closer to one power of two than the next higher one -- the average number of
michael@0: # comparisons can be reduced by splitting the top level check into more than 2.
michael@0: 
michael@0: import math
michael@0: 
michael@0: # List of style structs and their corresponding Check callback functions,
michael@0: # if any.
michael@0: STYLE_STRUCTS = [("INHERITED",) + x for x in [
michael@0:     # Inherited style structs.
michael@0:     ("Font",           "CheckFontCallback"),
michael@0:     ("Color",          "CheckColorCallback"),
michael@0:     ("List",           "nullptr"),
michael@0:     ("Text",           "CheckTextCallback"),
michael@0:     ("Visibility",     "nullptr"),
michael@0:     ("Quotes",         "nullptr"),
michael@0:     ("UserInterface",  "nullptr"),
michael@0:     ("TableBorder",    "nullptr"),
michael@0:     ("SVG",            "nullptr"),
michael@0:     ("Variables",      "CheckVariablesCallback"),
michael@0: ]] + [("RESET",) + x for x in [
michael@0:     # Reset style structs.
michael@0:     ("Background",     "nullptr"),
michael@0:     ("Position",       "nullptr"),
michael@0:     ("TextReset",      "nullptr"),
michael@0:     ("Display",        "nullptr"),
michael@0:     ("Content",        "nullptr"),
michael@0:     ("UIReset",        "nullptr"),
michael@0:     ("Table",          "nullptr"),
michael@0:     ("Margin",         "nullptr"),
michael@0:     ("Padding",        "nullptr"),
michael@0:     ("Border",         "nullptr"),
michael@0:     ("Outline",        "nullptr"),
michael@0:     ("XUL",            "nullptr"),
michael@0:     ("SVGReset",       "nullptr"),
michael@0:     ("Column",         "nullptr"),
michael@0: ]]
michael@0: 
michael@0: # How widely to branch on the outermost if statement.
michael@0: TOPLEVELBRANCHES = 4
michael@0: 
michael@0: 
michael@0: # ---- Generate nsStyleStructList.h ----
michael@0: 
michael@0: count = len(STYLE_STRUCTS)
michael@0: 
michael@0: def nextPowerOf2(x):
michael@0:     return int(pow(2, math.ceil(math.log(x, 2))))
michael@0: 
michael@0: def printEntry(i):
michael@0:     print "STYLE_STRUCT_%s(%s, %s)" % STYLE_STRUCTS[i]
michael@0: 
michael@0: def printTestTree(min, max, depth, branches):
michael@0:     indent = "  " * depth
michael@0:     if min == count - 1 and max >= count:
michael@0:         print "  STYLE_STRUCT_TEST_CODE(%sNS_ASSERTION(STYLE_STRUCT_TEST == %d, \"out of range\");)" % (indent, min)
michael@0:         printEntry(min)
michael@0:     elif max - min == 2:
michael@0:         print "  STYLE_STRUCT_TEST_CODE(%sif (STYLE_STRUCT_TEST == %d) {)" % (indent, min)
michael@0:         printEntry(min)
michael@0:         print "  STYLE_STRUCT_TEST_CODE(%s} else {)" % indent
michael@0:         printEntry(min + 1)
michael@0:         print "  STYLE_STRUCT_TEST_CODE(%s})" % indent
michael@0:     elif min < count:
michael@0:         mid = min + (max - min) / branches
michael@0:         print "  STYLE_STRUCT_TEST_CODE(%sif (STYLE_STRUCT_TEST < %d) {)" % (indent, mid)
michael@0:         printTestTree(min, mid, depth + 1, 2)
michael@0:         for branch in range(1, branches):
michael@0:             lo = min + branch * (max - min) / branches
michael@0:             hi = min + (branch + 1) * (max - min) / branches
michael@0:             if lo >= count:
michael@0:                 break
michael@0:             if branch == branches - 1 or hi >= count:
michael@0:                 print "  STYLE_STRUCT_TEST_CODE(%s} else {)" % indent
michael@0:             else:
michael@0:                 print "  STYLE_STRUCT_TEST_CODE(%s} else if (STYLE_STRUCT_TEST < %d) {)" % (indent, hi)
michael@0:             printTestTree(lo, hi, depth + 1, 2)
michael@0:         print "  STYLE_STRUCT_TEST_CODE(%s})" % indent
michael@0: 
michael@0: HEADER = """/* THIS FILE IS AUTOGENERATED BY generate-stylestructlist.py - DO NOT EDIT */
michael@0: 
michael@0: // IWYU pragma: private, include "nsStyleStructFwd.h"
michael@0: 
michael@0: /*
michael@0:  * list of structs that contain the data provided by nsStyleContext, the
michael@0:  * internal API for computed style data for an element
michael@0:  */
michael@0: 
michael@0: /*
michael@0:  * This file is intended to be used by different parts of the code, with
michael@0:  * the STYLE_STRUCT macro (or the STYLE_STRUCT_INHERITED and
michael@0:  * STYLE_STRUCT_RESET pair of macros) defined in different ways.
michael@0:  */
michael@0: 
michael@0: #ifndef STYLE_STRUCT_INHERITED
michael@0: #define STYLE_STRUCT_INHERITED(name, checkdata_cb) \\
michael@0:   STYLE_STRUCT(name, checkdata_cb)
michael@0: #define UNDEF_STYLE_STRUCT_INHERITED
michael@0: #endif
michael@0: 
michael@0: #ifndef STYLE_STRUCT_RESET
michael@0: #define STYLE_STRUCT_RESET(name, checkdata_cb) \\
michael@0:   STYLE_STRUCT(name, checkdata_cb)
michael@0: #define UNDEF_STYLE_STRUCT_RESET
michael@0: #endif
michael@0: 
michael@0: #ifdef STYLE_STRUCT_TEST
michael@0: #define STYLE_STRUCT_TEST_CODE(c) c
michael@0: #else
michael@0: #define STYLE_STRUCT_TEST_CODE(c)
michael@0: #endif
michael@0: 
michael@0: // The inherited structs are listed before the Reset structs.
michael@0: // nsStyleStructID assumes this is the case, and callers other than
michael@0: // nsStyleStructFwd.h that want the structs in id-order just define
michael@0: // STYLE_STRUCT rather than including the file twice.
michael@0: 
michael@0: """
michael@0: FOOTER = """
michael@0: #ifdef UNDEF_STYLE_STRUCT_INHERITED
michael@0: #undef STYLE_STRUCT_INHERITED
michael@0: #undef UNDEF_STYLE_STRUCT_INHERITED
michael@0: #endif
michael@0: 
michael@0: #ifdef UNDEF_STYLE_STRUCT_RESET
michael@0: #undef STYLE_STRUCT_RESET
michael@0: #undef UNDEF_STYLE_STRUCT_RESET
michael@0: #endif
michael@0: 
michael@0: #undef STYLE_STRUCT_TEST_CODE
michael@0: """
michael@0: 
michael@0: print HEADER
michael@0: printTestTree(0, nextPowerOf2(count), 0, TOPLEVELBRANCHES)
michael@0: print FOOTER