1if not modules then modules = { } end modules ['util-sac'] = {
2 version = 1.001,
3 optimize = true,
4 comment = "companion to luat-lib.mkiv",
5 author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
6 copyright = "PRAGMA ADE / ConTeXt Development Team",
7 license = "see context related readme files"
8}
9
10
11local byte, sub = string.byte, string.sub
12local tonumber = tonumber
13
14utilities = utilities or { }
15local streams = { }
16utilities.streams = streams
17
18function streams.open(filename,zerobased)
19 local f = filename and io.loaddata(filename)
20 if f then
21 return { f, 1, #f, zerobased or false }
22 end
23end
24
25function streams.openstring(f,zerobased)
26 if f then
27 return { f, 1, #f, zerobased or false }
28 end
29end
30
31function streams.getstring(f)
32 if f then
33 return f[1]
34 end
35end
36
37function streams.close()
38
39end
40
41function streams.size(f)
42 return f and f[3] or 0
43end
44
45streams.getsize = streams.size
46
47function streams.setposition(f,i)
48 if f[4] then
49
50 if i <= 0 then
51 f[2] = 1
52 else
53 f[2] = i + 1
54 end
55 else
56 if i <= 1 then
57 f[2] = 1
58 else
59 f[2] = i
60 end
61 end
62end
63
64function streams.getposition(f)
65 if f[4] then
66
67 return f[2] - 1
68 else
69 return f[2]
70 end
71end
72
73function streams.look(f,n,chars)
74 local b = f[2]
75 local e = b + n - 1
76 if chars then
77 return sub(f[1],b,e)
78 else
79 return byte(f[1],b,e)
80 end
81end
82
83function streams.skip(f,n)
84 f[2] = f[2] + n
85end
86
87
88
89function streams.readbyte(f)
90 local i = f[2]
91 f[2] = i + 1
92 return byte(f[1],i)
93end
94
95function streams.readbytes(f,n)
96 local i = f[2]
97 local j = i + n
98 f[2] = j
99 return byte(f[1],i,j-1)
100end
101
102function streams.readbytetable(f,n)
103 local i = f[2]
104 local j = i + n
105 f[2] = j
106 return { byte(f[1],i,j-1) }
107end
108
109function streams.skipbytes(f,n)
110 f[2] = f[2] + n
111end
112
113function streams.readchar(f)
114 local i = f[2]
115 f[2] = i + 1
116 return sub(f[1],i,i)
117end
118
119function streams.readstring(f,n)
120 local i = f[2]
121 local j = i + n
122 f[2] = j
123 return sub(f[1],i,j-1)
124end
125
126function streams.skipshort(f,n) f[2] = f[2] + 2*(n or 1) end
127function streams.skiplong (f,n) f[2] = f[2] + 4*(n or 1) end
128
129local readcardinal1 = sio.readcardinal1
130local readcardinal2 = sio.readcardinal2
131local readcardinal3 = sio.readcardinal3
132local readcardinal4 = sio.readcardinal4
133
134function streams.readcardinal1(f) local i = f[2] f[2] = i + 1 return readcardinal1(f[1],i) end
135function streams.readcardinal2(f) local i = f[2] f[2] = i + 2 return readcardinal2(f[1],i) end
136function streams.readcardinal3(f) local i = f[2] f[2] = i + 3 return readcardinal3(f[1],i) end
137function streams.readcardinal4(f) local i = f[2] f[2] = i + 4 return readcardinal4(f[1],i) end
138
139local readcardinal1le = sio.readcardinal1le
140local readcardinal2le = sio.readcardinal2le
141local readcardinal3le = sio.readcardinal3le
142local readcardinal4le = sio.readcardinal4le
143
144function streams.readcardinal1le(f) local i = f[2] f[2] = i + 1 return readcardinal1le(f[1],i) end
145function streams.readcardinal2le(f) local i = f[2] f[2] = i + 2 return readcardinal2le(f[1],i) end
146function streams.readcardinal3le(f) local i = f[2] f[2] = i + 3 return readcardinal3le(f[1],i) end
147function streams.readcardinal4le(f) local i = f[2] f[2] = i + 4 return readcardinal4le(f[1],i) end
148
149local readinteger1 = sio.readinteger1
150local readinteger2 = sio.readinteger2
151local readinteger3 = sio.readinteger3
152local readinteger4 = sio.readinteger4
153
154function streams.readinteger1(f) local i = f[2] f[2] = i + 1 return readinteger1(f[1],i) end
155function streams.readinteger2(f) local i = f[2] f[2] = i + 2 return readinteger2(f[1],i) end
156function streams.readinteger3(f) local i = f[2] f[2] = i + 3 return readinteger3(f[1],i) end
157function streams.readinteger4(f) local i = f[2] f[2] = i + 4 return readinteger4(f[1],i) end
158
159local readinteger1le = sio.readinteger1le
160local readinteger2le = sio.readinteger2le
161local readinteger3le = sio.readinteger3le
162local readinteger4le = sio.readinteger4le
163
164function streams.readinteger1le(f) local i = f[2] f[2] = i + 1 return readinteger1le(f[1],i) end
165function streams.readinteger2le(f) local i = f[2] f[2] = i + 2 return readinteger2le(f[1],i) end
166function streams.readinteger3le(f) local i = f[2] f[2] = i + 3 return readinteger3le(f[1],i) end
167function streams.readinteger4le(f) local i = f[2] f[2] = i + 4 return readinteger4le(f[1],i) end
168
169local readfixed2 = sio.readfixed2
170local readfixed4 = sio.readfixed4
171local read2dot14 = sio.read2dot14
172
173function streams.readfixed2(f) local i = f[2] f[2] = i + 2 return readfixed2(f[1],i) end
174function streams.readfixed4(f) local i = f[2] f[2] = i + 4 return readfixed4(f[1],i) end
175function streams.read2dot14(f) local i = f[2] f[2] = i + 2 return read2dot14(f[1],i) end
176
177local readcstring = sio.readcstring
178local readcline = sio.readcline
179
180function streams.readcstring(f)
181 local s, p = readcstring(f[1],f[2])
182 f[2] = p
183 return s
184end
185
186function streams.readcline(f,n)
187 local s, p = readcline(f[1],f[2])
188 f[2] = p
189 return s
190end
191
192local readbytes = sio.readbytes
193local readbytetable = sio.readbytetable
194
195function streams.readbytes(f,n)
196 local i = f[2]
197 local s = f[3]
198 local p = i + n
199 if p > s then
200 f[2] = s + 1
201 else
202 f[2] = p
203 end
204 return readbytes(f[1],i,n)
205end
206
207function streams.readbytetable(f,n)
208 local i = f[2]
209 local s = f[3]
210 local p = i + n
211 if p > s then
212 f[2] = s + 1
213 else
214 f[2] = p
215 end
216 return readbytetable(f[1],i,n)
217end
218
219streams.readbyte = streams.readcardinal1
220streams.readsignedbyte = streams.readinteger1
221streams.readcardinal1 = streams.readcardinal1
222streams.readcardinal = streams.readcardinal1
223streams.readinteger = streams.readinteger1
224streams.readinteger1 = streams.readinteger1
225
226local readcardinaltable = sio.readcardinaltable
227local readintegertable = sio.readintegertable
228
229function utilities.streams.readcardinaltable(f,n,b)
230 local i = f[2]
231 local s = f[3]
232 local p = i + n * b
233 if p > s then
234 f[2] = s + 1
235 else
236 f[2] = p
237 end
238 return readcardinaltable(f[1],i,n,b)
239end
240
241function utilities.streams.readintegertable(f,n,b)
242 local i = f[2]
243 local s = f[3]
244 local p = i + n * b
245 if p > s then
246 f[2] = s + 1
247 else
248 f[2] = p
249 end
250 return readintegertable(f[1],i,n,b)
251end
252
253
254
255
256local files = utilities.files
257
258if files then
259
260 local openfile = files.open
261 local openstream = streams.open
262 local openstring = streams.openstring
263
264 local setmetatable = setmetatable
265
266 function io.newreader(str,method)
267 local f, m
268 if method == "string" then
269 f = openstring(str,true)
270 m = streams
271 elseif method == "stream" then
272 f = openstream(str,true)
273 m = streams
274 else
275 f = openfile(str,"rb")
276 m = files
277 end
278 if f then
279 local t = { }
280 setmetatable(t, {
281 __index = function(t,k)
282 local r = m[k]
283 if k == "close" then
284 if f then
285 m.close(f)
286 f = nil
287 end
288 return function() end
289 elseif r then
290 local v = function(_,a,b) return r(f,a,b) end
291 t[k] = v
292 return v
293 else
294 print("unknown key",k)
295 end
296 end
297 } )
298 return t
299 end
300 end
301
302end
303
304streams.tocardinal1 = sio.tocardinal1
305streams.tocardinal2 = sio.tocardinal2
306streams.tocardinal3 = sio.tocardinal3
307streams.tocardinal4 = sio.tocardinal4
308
309streams.tocardinal1le = sio.tocardinal1le
310streams.tocardinal2le = sio.tocardinal2le
311streams.tocardinal3le = sio.tocardinal3le
312streams.tocardinal4le = sio.tocardinal4le
313 |
