/usr/share/gnu-smalltalk/kernel/DLD.st is in gnu-smalltalk-common 3.2.5-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 | "======================================================================
|
| Dynamic Loader Method Definitions
|
|
======================================================================"
"======================================================================
|
| Copyright 1992,94,95,99,2000,2001,2002,2003,2005,2008,2009
| Free Software Foundation, Inc.
| Written by Steve Byrne.
|
| This file is part of the GNU Smalltalk class library.
|
| The GNU Smalltalk class library is free software; you can redistribute it
| and/or modify it under the terms of the GNU Lesser General Public License
| as published by the Free Software Foundation; either version 2.1, or (at
| your option) any later version.
|
| The GNU Smalltalk class library is distributed in the hope that it will be
| useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
| General Public License for more details.
|
| You should have received a copy of the GNU Lesser General Public License
| along with the GNU Smalltalk class library; see the file COPYING.LIB.
| If not, write to the Free Software Foundation, 59 Temple Place - Suite
| 330, Boston, MA 02110-1301, USA.
|
======================================================================"
Namespace current: Kernel [
Stream subclass: RoundRobinStream [
| stream first last |
<category: 'Language-C interface'>
<comment: 'This class implements a peculiar stream that optimizes the order
in which symbols are searched in dynamically linked libraries.
When using #next, the stream will restart from the first element
after returning nil once. When you use #do:, the stream starts
from the *last* element that was either returned by #next or passed
to #do: in the previous iteration.
Since the #primDefineExternFunc: leaves the #do: in advance if it
succeeds in finding a symbol, the next time it will restart from
the library in which it found a symbol. Usually symbols have a
very good locality (you find all the symbols in a library, or at
least symbols in the same #methodsFor: come from the same library):
so this avoids looking for symbols in the wrong library.'>
RoundRobinStream class >> test: s get: n [
<category: 'demo'>
n timesRepeat: [s next print].
Transcript nl
]
RoundRobinStream class >> test: s leaveAfter: n [
<category: 'demo'>
| i |
i := 0.
s do:
[:each |
each print.
(i := i + 1) = n
ifTrue:
[Transcript nl.
^nil]].
Transcript nl
]
RoundRobinStream class >> testOn: anArray [
"RoundRobinStream testOn: #(1 2 3 4 5 6)"
<category: 'demo'>
| s |
s := RoundRobinStream on: anArray readStream.
self test: s get: anArray size + 1.
self test: s get: anArray size + 1.
self test: s get: (anArray size + 1) * 2.
self test: s get: 2.
self test: s leaveAfter: anArray size + 1.
self test: s leaveAfter: anArray size + 1.
self test: s leaveAfter: 1.
self test: s leaveAfter: 1.
self test: s leaveAfter: 2.
self test: s leaveAfter: 2.
self test: s leaveAfter: anArray size + 1.
self test: s leaveAfter: anArray size + 1.
Transcript nl
]
RoundRobinStream class >> on: aStream [
<category: 'accessing'>
^self new stream: aStream
]
stream [
<category: 'accessing'>
^stream
]
stream: aStream [
<category: 'accessing'>
stream := aStream
]
atEnd [
<category: 'basic'>
stream atEnd
ifTrue:
[stream reset.
"If there is no established first, we started iterating from the
first element in the stream."
first isNil ifTrue: [^true]].
^(last := stream peek) == first
]
next [
<category: 'basic'>
^self atEnd
ifTrue: [SystemExceptions.EndOfStream signalOn: self]
ifFalse: [stream next]
]
do: aBlock [
"Iterate on all the items in the Stream. If it is not the first iteration,
and the last item was retrieved with #next or passed to a #do: block *that
did a global return*, return from there."
<category: 'basic'>
stream atEnd
ifTrue:
[stream reset.
stream atEnd ifTrue: [^self]].
"Establish the item at which we'll stop iterating. Start from that one."
last isNil ifTrue: [last := stream next].
first := last.
aBlock value: last.
super do: aBlock.
"Make sure we will not restart from the last item we passed to aBlock,
because aBlock did not return."
last := nil
]
]
]
Object subclass: DLD [
<category: 'Language-C interface'>
<comment: '...and Gandalf said:
``Many folk like to know beforehand what is to be set on the
table; but those who have laboured to prepare the feast like
to keep their secret; for wonder makes the words of praise
louder.''''
I am just an ancillary class used to reference some C functions.
Most of my actual functionality is used by redefinitions of methods
in CFunctionDescriptor.'>
DLD class [
| libraryList libraryStream moduleList |
]
DLD class >> linkFile: aFileName [
"Private-used by addLibrary: and addModule:."
<category: 'private-C call-outs'>
<cCall: 'dldLink' returning: #cObject args: #(#string)>
]
DLD class >> library: libHandle getFunc: aFuncString [
"Private-used for library searches."
<category: 'private-C call-outs'>
<cCall: 'dldGetFunc' returning: #cObject args: #(#cObject #string)>
]
DLD class >> defineCFunc: aName as: aFuncAddr [
"Register aFuncAddr as the target for cCalls to aName."
<category: 'C call-outs'>
<cCall: 'defineCFunc' returning: #void args: #(#string #cObject)>
]
DLD class >> defineExternFunc: aFuncName [
"This method calls #primDefineExternFunc: to try to link to a function with
the given name, and answers whether the linkage was successful. You can
redefine this method to restrict the ability to do dynamic linking."
<category: 'dynamic linking'>
^self primDefineExternFunc: aFuncName
]
DLD class >> primDefineExternFunc: aFuncName [
"This method tries to link to a function with the given name, and answers
whether the linkage was successful. It should not be overridden."
<category: 'dynamic linking'>
| couldNotLink |
libraryStream do:
[:lib |
| funcAddr |
lib value notNil
ifTrue:
[funcAddr := self library: lib value getFunc: aFuncName.
funcAddr notNil
ifTrue:
[self defineCFunc: aFuncName as: funcAddr.
^true]]].
^false
]
DLD class >> initialize [
"Private - Initialize the receiver's class variables"
<category: 'dynamic linking'>
libraryList := OrderedCollection new.
libraryStream := Kernel.RoundRobinStream on: libraryList readStream.
moduleList := OrderedCollection new.
]
DLD class >> update: aspect [
"Called on startup - Make DLD re-link and reset the addresses of
all the externally defined functions"
<category: 'dynamic linking'>
| notLoaded |
aspect == #returnFromSnapshot ifFalse: [^self].
libraryList := libraryList reject: [:lib | lib key isNil].
libraryList do: [:lib | lib value: (self linkFile: lib key)].
notLoaded := WriteStream on: Array new.
moduleList
do: [:each | (self linkFile: each) isNil ifTrue: [notLoaded nextPut: each]].
notLoaded := notLoaded contents.
notLoaded isEmpty
ifFalse:
[SystemExceptions.CInterfaceError
signal: 'modules ' , notLoaded printString , ' could not be loaded.']
]
DLD class >> libraryList [
"Answer a copy of the search path of libraries to be used by DLD"
<category: 'dynamic linking'>
^(libraryList select: [:each | each key notNil])
collect: [:each | each key]
]
DLD class >> moduleList [
"Answer a copy of the modules reloaded when the image is started"
<category: 'dynamic linking'>
^moduleList copy
]
DLD class >> addLibrary: library [
"Add library to the search path of libraries to be used by DLD."
<category: 'dynamic linking'>
(libraryList anySatisfy: [:anAssociation | anAssociation key = library])
ifFalse:
[libraryList add: library -> (self linkFile: library).
libraryStream := Kernel.RoundRobinStream on: libraryList readStream]
]
DLD class >> addLibraryHandle: libraryHandle [
"This is called internally by gst_dlopen. The library will
be open and put in the search path."
<category: 'dynamic linking'>
libraryList add: nil -> libraryHandle.
libraryStream := Kernel.RoundRobinStream on: libraryList readStream
]
DLD class >> addModule: library [
"Add library to the list of modules to be loaded when the image is
started. The gst_initModule function in the library is called,
but the library will not be put in the search path used whenever
a C function is requested but not registered."
<category: 'dynamic linking'>
(moduleList includes: library)
ifFalse:
[(self linkFile: library) isNil
ifTrue:
[SystemExceptions.CInterfaceError
signal: 'requested module ' , library , ' was not found']
ifFalse: [moduleList add: library]]
]
]
CFunctionDescriptor class extend [
addressOf: function [
"Answer whether a function is registered (on the C side) with the
given name or is dynamically loadable."
<category: 'testing'>
<primitive: VMpr_CFuncDescriptor_addressOf>
^(DLD defineExternFunc: function)
ifTrue: [self addressOf: function] "Try again."
ifFalse: [CObject new]
]
]
Eval [
DLD initialize
]
|