about summary refs log tree commit diff stats
path: root/088file.mu
blob: 3c31e66f999dd203a29340a77a4b72a8dca60f8a (plain) (blame)
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
# Wrappers around file system primitives that take a 'resources' object and
# are thus easier to test.

container resources [
  data:&:@:resource
]

container resource [
  name:text
  contents:text
]

def start-reading resources:&:resources, filename:text -> contents:&:source:char [
  local-scope
  load-ingredients
  {
    break-unless resources
    # fake file system
    contents <- start-reading-from-fake-resources resources, filename
    return
  }
  # real file system
  file:num <- $open-file-for-reading filename
  assert file, [file not found]
  contents:&:source:char, sink:&:sink:char <- new-channel 30
  start-running receive-from-file file, sink
]

def start-reading-from-fake-resources resources:&:resources, resource:text -> contents:&:source:char [
  local-scope
  load-ingredients
  i:num <- copy 0
  data:&:@:resource <- get *resources, data:offset
  len:num <- length *data
  {
    done?:bool <- greater-or-equal i, len
    break-if done?
    tmp:resource <- index *data, i
    i <- add i, 1
    curr-resource:text <- get tmp, name:offset
    found?:bool <- equal resource, curr-resource
    loop-unless found?
    contents:&:source:char, sink:&:sink:char <- new-channel 30
    curr-contents:text <- get tmp, contents:offset
    start-running receive-from-text curr-contents, sink
    return
  }
  return 0/not-found
]

def receive-from-file file:num, sink:&:sink:char -> sink:&:sink:char [
  local-scope
  load-ingredients
  {
    c:char, eof?:bool <- $read-from-file file
    break-if eof?
    sink <- write sink, c
    loop
  }
  sink <- close sink
  file <- $close-file file
]

def receive-from-text contents:text, sink:&:sink:char -> sink:&:sink:char [
  local-scope
  load-ingredients
  i:num <- copy 0
  len:num <- length *contents
  {
    done?:bool <- greater-or-equal i, len
    break-if done?
    c:char <- index *contents, i
    sink <- write sink, c
    i <- add i, 1
    loop
  }
  sink <- close sink
]

def start-writing resources:&:resources, filename:text -> sink:&:sink:char, routine-id:num [
  local-scope
  load-ingredients
  source:&:source:char, sink:&:sink:char <- new-channel 30
  {
    break-unless resources
    # fake file system
    # beware: doesn't support multiple concurrent writes yet
    routine-id <- start-running transmit-to-fake-file resources, filename, source
    reply
  }
  # real file system
  file:num <- $open-file-for-writing filename
  assert file, [no such file]
  routine-id <- start-running transmit-to-file file, source
]

def transmit-to-file file:num, source:&:source:char -> source:&:source:char [
  local-scope
  load-ingredients
  {
    c:char, done?:bool, source <- read source
    break-if done?
    $write-to-file file, c
    loop
  }
  file <- $close-file file
]

def transmit-to-fake-file resources:&:resources, filename:text, source:&:source:char -> resources:&:resources, source:&:source:char [
  local-scope
  load-ingredients
  # compute new file contents
  buf:&:buffer <- new-buffer 30
  {
    c:char, done?:bool, source <- read source
    break-if done?
    buf <- append buf, c
    loop
  }
  contents:text <- buffer-to-array buf
  new-resource:resource <- merge filename, contents
  # write to resources
  curr-filename:text <- copy 0
  data:&:@:resource <- get *resources, data:offset
  # replace file contents if it already exists
  i:num <- copy 0
  len:num <- length *data
  {
    done?:bool <- greater-or-equal i, len
    break-if done?
    tmp:resource <- index *data, i
    curr-filename <- get tmp, name:offset
    found?:bool <- equal filename, curr-filename
    loop-unless found?
    put-index *data, i, new-resource
    reply
  }
  # if file didn't already exist, make room for it
  new-len:num <- add len, 1
  new-data:&:@:resource <- new resource:type, new-len
  put *resources, data:offset, new-data
  # copy over old files
  i:num <- copy 0
  {
    done?:bool <- greater-or-equal i, len
    break-if done?
    tmp:resource <- index *data, i
    put-index *new-data, i, tmp
  }
  # write new file
  put-index *new-data, len, new-resource
]