summaryrefslogtreecommitdiff
path: root/Master/texmf-dist/tex/context/base/util-pck.lua
blob: c802a09ed8120f2ef423a9800ce063f398399c2c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
if not modules then modules = { } end modules ['util-pck'] = {
    version   = 1.001,
    comment   = "companion to luat-lib.mkiv",
    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
    copyright = "PRAGMA ADE / ConTeXt Development Team",
    license   = "see context related readme files"
}

-- moved from core-uti

local next, tostring, type = next, tostring, type
local sort, concat = table.sort, table.concat

utilities         = utilities         or { }
utilities.packers = utilities.packers or { }
local packers     = utilities.packers
packers.version   = 1.00

local function hashed(t)
    local s, ns = { }, 0
    for k, v in next, t do
        ns = ns + 1
        if type(v) == "table" then
            s[ns] = k .. "={" .. hashed(v) .. "}"
        else
            s[ns] = k .. "=" .. tostring(v)
        end
    end
    sort(s)
    return concat(s,",")
end

local function simplehashed(t)
    local s, ns = { }, 0
    for k, v in next, t do
        ns = ns + 1
        s[ns] = k .. "=" .. v
    end
    sort(s)
    return concat(s,",")
end

packers.hashed       = hashed
packers.simplehashed = simplehashed

--~ local function pack(t,keys,hash,index)
--~     for k,v in next, t do
--~         if type(v) == "table" then
--~             pack(v,keys,hash,index)
--~         end
--~         if keys[k] and type(v) == "table" then
--~             local h = hashed(v)
--~             local i = hash[h]
--~             if not i then
--~                 i = #index + 1
--~                 index[i] = v
--~                 hash[h] = i
--~             end
--~             t[k] = i
--~         end
--~     end
--~ end

local function pack(t,keys,hash,index)
    for k,v in next, t do
        if type(v) == "table" then
            pack(v,keys,hash,index)
            if keys[k] then
                local h = hashed(v)
                local i = hash[h]
                if not i then
                    i = #index + 1
                    index[i] = v
                    hash[h] = i
                end
                t[k] = i
            end
        end
    end
end

local function unpack(t,keys,index)
    for k,v in next, t do
        if keys[k] and type(v) == "number" then
            local iv = index[v]
            if iv then
                v = iv
                t[k] = v
            end
        end
        if type(v) == "table" then
            unpack(v,keys,index)
        end
    end
end

function packers.new(keys,version)
    return {
        version = version or packers.version,
        keys    = table.tohash(keys),
        hash    = { },
        index   = { },
    }
end

function packers.pack(t,p,shared)
    if shared then
        pack(t,p.keys,p.hash,p.index)
    elseif not t.packer then
        pack(t,p.keys,p.hash,p.index)
        if #p.index > 0 then
            t.packer = {
                version = p.version or packers.version,
                keys = p.keys,
                index = p.index,
            }
        end
        p.hash, p.index = { }, { }
    end
end

function packers.unpack(t,p,shared)
    if shared then
        if p then
            unpack(t,p.keys,p.index)
        end
    else
        local tp = t.packer
        if tp then
            if tp.version == (p and p.version or packers.version) then
                unpack(t,tp.keys,tp.index)
            else
                -- fatal error, wrong version
            end
            t.packer = nil
        end
    end
end

function packers.strip(p)
    p.hash = nil
end