summary refs log blame commit diff stats
path: root/TODO
blob: f5e5536f287306997f28e5473cd2760f12dd1de6 (plain) (tree)
1
2
3
4
5
6
7
8
9
10
11

       

                                      
                               
                                         
                                                    



       
                                                    
                                           
                                     
                                                                

                                                                  
                            
                                                               
                                                        
                                                        
                                       

                                                             

                                                  
                                                                        



    
                                                           
                                                              
                                               
                                                                   
                                                                 
                                                              
                                             




                                                               
                                  

                                                                     
                                                 
Console

   (X) #0   09/12/06  console commands
   (X) #1   09/12/06  quick find
   (X) #2   09/12/06  open with
   (X) #4   09/12/06  history for console
   (X) #13  09/12/27  display docstring of a command


General

   (X) #5   09/12/06  move code from fm into objects
   (X) #6   09/12/06  move main to __init__
   (X) #7   09/12/06  cooler titlebar
   (X) #8   09/12/17  Add operations to modify files/directories
   (X) #9   09/12/24  add a widget for managing running operations
   (X) #10  09/12/24  sorting
   (X) #11  09/12/27  filter
   (X) #12  09/12/27  jump through the list in a specific order
   (X) #14  09/12/29  make filelists inherit from pagers
   (X) #15  09/12/29  better way of running processes!!~
   (X) #16  10/01/01  list of bookmarks
   (X) #21  10/01/01  write help!
   ( ) #22  10/01/03  add getopt options to change flags/mode
   ( ) #29  10/01/06  add chmod command
   ( ) #30  10/01/06  add a way to create symlinks
   ( ) #32  10/01/08  place the (hidden) cursor to a meaningful position


Bugs

   (X) #17  10/01/01  why do bookmarks disappear sometimes?
   (X) #18  10/01/01  fix notify widget (by adding a LogView?)
   (X) #19  10/01/01  resizing after pressing g
   (X) #23  10/01/04  stop dir loading with ^C -> wont load anymore
   (X) #25  10/01/06  directories sometimes dont reload correctly
   (X) #26  10/01/06  :delete on symlinks of directories fails
   ( ) #31  10/01/06  ^C breaks cd-after-exit


Ideas

   ( ) #20  10/01/01  use inotify to monitor filesystem changes
   ( ) #24  10/01/06  progress bar
   ( ) #27  10/01/06  hide bookmarks in list which contain hidden dir
   ( ) #28  10/01/06  use regexp instead of string for searching
   ( ) #33  10/01/08  accelerate mousewheel speed
f='/akkartik/mu/commit/034address.cc?h=main&id=7fd010710c0a34ff103bec3fb271f0c207bfcc53'>7fd01071 ^
b0bf5321 ^

7fd01071 ^
9a6f8798 ^
b0bf5321 ^




b0bf5321 ^
dc9afcbd ^

b0bf5321 ^
dc9afcbd ^
b0bf5321 ^


9a6f8798 ^
b0bf5321 ^


































192d59d3 ^
b0bf5321 ^
dc9afcbd ^
b0bf5321 ^


192d59d3 ^


b0bf5321 ^

2efceef6 ^

b0bf5321 ^



192d59d3 ^


b0bf5321 ^

2efceef6 ^

b0bf5321 ^





192d59d3 ^
b0bf5321 ^



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
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378















                                                                              



                                                                              





                                                                             

                                                                            









                                                                             


                                                                              





                                                                             
                                         




































                                                                             
                                





























                                                                                 

                                                                             
 





                                                                                       

                                      
                                                          


                             

                                    
                                                       


                                       



                                                                         
                                           










                                                               
                                                                                                                                


                                
                                               
                                  
                                                                                                                                     






                                                                                        
                                                                                                                      





                                                       
                                                
                                
                                                                                                       



                                     

                                                                                                       

                                     
                                                                     





                                                                                 


                                                         
                                                       

                                            
                                                                                            







                          




























                                                                                                                                                       
                                               











                                                                                                                  
                                           






















                                                                                                
                                                                                 

                                                                











                                                                                                                         
                               
         

                                                            
                  
                           




                                                         
                               

                                                                       
                            
   


                                                               
                


































                                                                                                                                      
                                  
 
                              


                     


                                                                  

                                                                                          

                                                                                                  



                             


                                                                  

                                                                                          

                                                         





                                                                                   
                                      



                                                                          
//: Addresses help us spend less time copying data around.

//: So far we've been operating on primitives like numbers and characters, and
//: we've started combining these primitives together into larger logical
//: units (containers or arrays) that may contain many different primitives at
//: once. Containers and arrays can grow quite large in complex programs, and
//: we'd like some way to efficiently share them between recipes without
//: constantly having to make copies. Right now 'next-ingredient' and 'reply'
//: copy data across recipe boundaries. To avoid copying large quantities of
//: data around, we'll use *addresses*. An address is a bookmark to some
//: arbitrary quantity of data (the *payload*). It's a primitive, so it's as
//: efficient to copy as a number. To read or modify the payload 'pointed to'
//: by an address, we'll perform a *lookup*.
//:
//: The notion of 'lookup' isn't an instruction like 'add' or 'subtract'.
//: Instead it's an operation that can be performed when reading any of the
//: ingredients of an instruction, and when writing to any of the products. To
//: write to the payload of an ingredient rather than its value, simply add
//: the /lookup property to it. Modern computers provide efficient support for
//: addresses and lookups, making this a realistic feature.
//:
//: To recap: an address is a bookmark to some potentially large payload, and
//: you can replace any ingredient or product with a lookup to an address of
//: the appropriate type. But how do we get addresses to begin with? That
//: requires a little more explanation. Once we introduce the notion of
//: bookmarks to data, we have to think about the life cycle of a piece of
//: data and its bookmarks (because remember, bookmarks can be copied around
//: just like anything else). Otherwise several bad outcomes can result (and
//: indeed *have* resulted in past languages like C):
//:
//:   a) You can run out of memory if you don't have a way to reclaim
//:   data.
//:   b) If you allow data to be reclaimed, you have to be careful not to
//:   leave any stale addresses pointing at it. Otherwise your program might
//:   try to lookup such an address and find something unexpected. Such
//:   problems can be very hard to track down, and they can also be exploited
//:   to break into your computer over the network, etc.
//:
//: To avoid these problems, we introduce the notion of a *reference count* or
//: refcount. The life cycle of a bit of data accessed through addresses looks
//: like this.
//:
//:    We create space in computer memory for it using the 'new' instruction.
//:    The 'new' instruction takes a type as an ingredient, allocates
//:    sufficient space to hold that type, and returns an address (bookmark)
//:    to the allocated space.
//:
//:      x:address:num <- new number:type
//:
//:                     +------------+
//:          x -------> |  number    |
//:                     +------------+
//:
//:    That isn't entirely accurate. Under the hood, 'new' allocates an extra
//:    number -- the refcount:
//:
//:                     +------------+------------+
//:          x -------> | refcount   |  number    |
//:                     +------------+------------+
//:
//:    This probably seems like a waste of space. In practice it isn't worth
//:    allocating individual numbers and our payload will tend to be larger,
//:    so the picture would look more like this (zooming out a bit):
//:
//:                         +-------------------------+
//:                     +---+                         |
//:          x -------> | r |                         |
//:                     +---+        DATA             |
//:                         |                         |
//:                         |                         |
//:                         +-------------------------+
//:
//:    (Here 'r' denotes the refcount. It occupies a tiny amount of space
//:    compared to the payload.)
//:
//:    Anyways, back to our example where the data is just a single number.
//:    After the call to 'new', Mu's map of memory looks like this:
//:
//:                     +---+------------+
//:          x -------> | 1 |  number    |
//:                     +---+------------+
//:
//:    The refcount of 1 here indicates that this number has one bookmark
//:    outstanding. If you then make a copy of x, the refcount increments:
//:
//:      y:address:num <- copy x
//:
//:          x ---+     +---+------------+
//:               +---> | 2 |  number    |
//:          y ---+     +---+------------+
//:
//:    Whether you access the payload through x or y, Mu knows how many
//:    bookmarks are outstanding to it. When you change x or y, the refcount
//:    transparently decrements:
//:
//:      x <- copy 0  # an address is just a number, you can always write 0 to it
//:
//:                     +---+------------+
//:          y -------> | 1 |  number    |
//:                     +---+------------+
//:
//:    The final flourish is what happens when the refcount goes down to 0: Mu
//:    reclaims the space occupied by both refcount and payload in memory, and
//:    they're ready to be reused by later calls to 'new'.
//:
//:      y <- copy 0
//:
//:                     +---+------------+
//:                     | 0 |  XXXXXXX   |
//:                     +---+------------+
//:
//: Using refcounts fixes both our problems a) and b) above: you can use
//: memory for many different purposes as many times as you want without
//: running out of memory, and you don't have to worry about ever leaving a
//: dangling bookmark when you reclaim memory.
//:
//: This layer implements creating addresses using 'new'. The next few layers
//: will flesh out the rest of the life cycle.

//: todo: give 'new' a custodian ingredient. Following malloc/free is a temporary hack.

:(scenario new)
# call 'new' two times with identical types without modifying the results; you
# should get back different results
def main [
  1:address:num/raw <- new number:type
  2:address:num/raw <- new number:type
  3:bool/raw <- equal 1:address:num/raw, 2:address:num/raw
]
+mem: storing 0 in location 3

:(scenario dilated_reagent_with_new)
def main [
  1:address:address:num <- new {(address number): type}
]
+new: size of ("address" "number") is 1

//: 'new' takes a weird 'type' as its first ingredient; don't error on it
:(before "End Mu Types Initialization")
put(Type_ordinal, "type", 0);
:(code)
bool is_mu_type_literal(const reagent& r) {
  return is_literal(r) && r.type && r.type->name == "type";
}

:(before "End Primitive Recipe Declarations")
NEW,
:(before "End Primitive Recipe Numbers")
put(Recipe_ordinal, "new", NEW);
:(before "End Primitive Recipe Checks")
case NEW: {
  const recipe& caller = get(Recipe, r);
  if (inst.ingredients.empty() || SIZE(inst.ingredients) > 2) {
    raise << maybe(caller.name) << "'new' requires one or two ingredients, but got '" << inst.original_string << "'\n" << end();
    break;
  }
  // End NEW Check Special-cases
  const reagent& type = inst.ingredients.at(0);
  if (!is_mu_type_literal(type)) {
    raise << maybe(caller.name) << "first ingredient of 'new' should be a type, but got '" << type.original_string << "'\n" << end();
    break;
  }
  if (inst.products.empty()) {
    raise << maybe(caller.name) << "result of 'new' should never be ignored\n" << end();
    break;
  }
  if (!product_of_new_is_valid(inst)) {
    raise << maybe(caller.name) << "product of 'new' has incorrect type: '" << inst.original_string << "'\n" << end();
    break;
  }
  break;
}
:(code)
bool product_of_new_is_valid(const instruction& inst) {
  reagent/*copy*/ product = inst.products.at(0);
  // Update NEW product in Check
  if (!product.type || product.type->atom || product.type->left->value != get(Type_ordinal, "address"))
    return false;
  drop_from_type(product, "address");
  if (SIZE(inst.ingredients) > 1) {
    // array allocation
    if (!product.type || product.type->atom || product.type->left->value != get(Type_ordinal, "array"))
      return false;
    drop_from_type(product, "array");
  }
  reagent/*copy*/ expected_product("x:"+inst.ingredients.at(0).name);
  {
    string_tree* tmp_type_names = parse_string_tree(expected_product.type->name);
    delete expected_product.type;
    expected_product.type = new_type_tree(tmp_type_names);
    delete tmp_type_names;
  }
  return types_strictly_match(product, expected_product);
}

void drop_from_type(reagent& r, string expected_type) {
  assert(!r.type->atom);
  if (r.type->left->name != expected_type) {
    raise << "can't drop2 " << expected_type << " from '" << to_string(r) << "'\n" << end();
    return;
  }
  type_tree* tmp = r.type;
  r.type = tmp->right;
  tmp->right = NULL;
  delete tmp;
}

//: To implement 'new', a Mu transform turns all 'new' instructions into
//: 'allocate' instructions that precompute the amount of memory they want to
//: allocate.

//: Ensure that we never call 'allocate' directly, and that there's no 'new'
//: instructions left after the transforms have run.
:(before "End Primitive Recipe Checks")
case ALLOCATE: {
  raise << "never call 'allocate' directly'; always use 'new'\n" << end();
  break;
}
:(before "End Primitive Recipe Implementations")
case NEW: {
  raise << "no implementation for 'new'; why wasn't it translated to 'allocate'? Please save a copy of your program and send it to Kartik.\n" << end();
  break;
}

:(after "Transform.push_back(check_instruction)")  // check_instruction will guard against direct 'allocate' instructions below
Transform.push_back(transform_new_to_allocate);  // idempotent

:(code)
void transform_new_to_allocate(const recipe_ordinal r) {
  trace(9991, "transform") << "--- convert 'new' to 'allocate' for recipe " << get(Recipe, r).name << end();
  for (int i = 0; i < SIZE(get(Recipe, r).steps); ++i) {
    instruction& inst = get(Recipe, r).steps.at(i);
    // Convert 'new' To 'allocate'
    if (inst.name == "new") {
      inst.operation = ALLOCATE;
      string_tree* type_name = new string_tree(inst.ingredients.at(0).name);
      type_name = parse_string_tree(type_name);
      type_tree* type = new_type_tree(type_name);
      inst.ingredients.at(0).set_value(size_of(type));
      trace(9992, "new") << "size of " << to_string(type_name) << " is " << inst.ingredients.at(0).value << end();
      delete type;
      delete type_name;
    }
  }
}

//: implement 'allocate' based on size

:(before "End Globals")
extern const int Reserved_for_tests = 1000;
int Memory_allocated_until = Reserved_for_tests;
int Initial_memory_per_routine = 100000;
:(before "End Setup")
Memory_allocated_until = Reserved_for_tests;
Initial_memory_per_routine = 100000;
:(before "End routine Fields")
int alloc, alloc_max;
:(before "End routine Constructor")
alloc = Memory_allocated_until;
Memory_allocated_until += Initial_memory_per_routine;
alloc_max = Memory_allocated_until;
trace(9999, "new") << "routine allocated memory from " << alloc << " to " << alloc_max << end();

:(before "End Primitive Recipe Declarations")
ALLOCATE,
:(before "End Primitive Recipe Numbers")
put(Recipe_ordinal, "allocate", ALLOCATE);
:(before "End Primitive Recipe Implementations")
case ALLOCATE: {
  // compute the space we need
  int size = ingredients.at(0).at(0);
  if (SIZE(ingredients) > 1) {
    // array allocation
    trace(9999, "mem") << "array length is " << ingredients.at(1).at(0) << end();
    size = /*space for length*/1 + size*ingredients.at(1).at(0);
  }
  int result = allocate(size);
  if (SIZE(current_instruction().ingredients) > 1) {
    // initialize array length
    trace(9999, "mem") << "storing " << ingredients.at(1).at(0) << " in location " << result+/*skip refcount*/1 << end();
    put(Memory, result+/*skip refcount*/1, ingredients.at(1).at(0));
  }
  products.resize(1);
  products.at(0).push_back(result);
  break;
}
:(code)
int allocate(int size) {
  // include space for refcount
  ++size;
  trace(9999, "mem") << "allocating size " << size << end();
//?   Total_alloc += size;
//?   ++Num_alloc;
  // Allocate Special-cases
  // compute the region of memory to return
  // really crappy at the moment
  ensure_space(size);
  const int result = Current_routine->alloc;
  trace(9999, "mem") << "new alloc: " << result << end();
  // initialize allocated space
  for (int address = result; address < result+size; ++address) {
    trace(9999, "mem") << "storing 0 in location " << address << end();
    put(Memory, address, 0);
  }
  Current_routine->alloc += size;
  // no support yet for reclaiming memory between routines
  assert(Current_routine->alloc <= Current_routine->alloc_max);
  return result;
}

//: statistics for debugging
//? :(before "End Globals")
//? int Total_alloc = 0;
//? int Num_alloc = 0;
//? int Total_free = 0;
//? int Num_free = 0;
//? :(before "End Setup")
//? Total_alloc = Num_alloc = Total_free = Num_free = 0;
//? :(before "End Teardown")
//? cerr << Total_alloc << "/" << Num_alloc
//?      << " vs " << Total_free << "/" << Num_free << '\n';
//? cerr << SIZE(Memory) << '\n';

:(code)
void ensure_space(int size) {
  if (size > Initial_memory_per_routine) {
    tb_shutdown();
    cerr << "can't allocate " << size << " locations, that's too much compared to " << Initial_memory_per_routine << ".\n";
    exit(0);
  }
  if (Current_routine->alloc + size > Current_routine->alloc_max) {
    // waste the remaining space and create a new chunk
    Current_routine->alloc = Memory_allocated_until;
    Memory_allocated_until += Initial_memory_per_routine;
    Current_routine->alloc_max = Memory_allocated_until;
    trace(9999, "new") << "routine allocated memory from " << Current_routine->alloc << " to " << Current_routine->alloc_max << end();
  }
}

:(scenario new_initializes)
% Memory_allocated_until = 10;
% put(Memory, Memory_allocated_until, 1);
def main [
  1:address:num <- new number:type
]
+mem: storing 0 in location 10

:(scenario new_array)
def main [
  1:address:array:num/raw <- new number:type, 5
  2:address:num/raw <- new number:type
  3:num/raw <- subtract 2:address:num/raw, 1:address:array:num/raw
]
+run: {1: ("address" "array" "number"), "raw": ()} <- new {number: "type"}, {5: "literal"}
+mem: array length is 5
# don't forget the extra location for array length, and the second extra location for the refcount
+mem: storing 7 in location 3

:(scenario new_empty_array)
def main [
  1:address:array:num/raw <- new number:type, 0
  2:address:num/raw <- new number:type
  3:num/raw <- subtract 2:address:num/raw, 1:address:array:num/raw
]
+run: {1: ("address" "array" "number"), "raw": ()} <- new {number: "type"}, {0: "literal"}
+mem: array length is 0
# one location for array length, and one for the refcount
+mem: storing 2 in location 3

//: If a routine runs out of its initial allocation, it should allocate more.
:(scenario new_overflow)
% Initial_memory_per_routine = 3;  // barely enough room for point allocation below
def main [
  1:address:num/raw <- new number:type
  2:address:point/raw <- new point:type  # not enough room in initial page
]
+new: routine allocated memory from 1000 to 1003
+new: routine allocated memory from 1003 to 1006