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
|
import std/options
import std/os
import std/strutils
import utils/sandbox
import utils/twtstr
{.passc: "-fno-strict-aliasing".}
{.passl: "-fno-strict-aliasing".}
{.compile: "stb_image.c".}
type stbi_io_callbacks = object
read: proc(user: pointer; data: ptr uint8; size: cint): cint {.cdecl.}
skip: proc(user: pointer; n: cint) {.cdecl.}
eof: proc(user: pointer): cint {.cdecl.}
proc stbi_load_from_callbacks(clbk: ptr stbi_io_callbacks; user: pointer;
x, y, channels_in_file: var cint; desired_channels: cint):
ptr UncheckedArray[uint8] {.importc.}
proc stbi_failure_reason(): cstring {.importc.}
proc stbi_image_free(retval_from_stbi_load: pointer) {.importc.}
proc myRead(user: pointer; data: ptr uint8; size: cint): cint {.cdecl.} =
return cint(stdin.readBuffer(data, size))
proc mySkip(user: pointer; n: cint) {.cdecl.} =
var data: array[4096, uint8]
let n = int(n)
var i = 0
while i < n:
let j = stdin.readBuffer(addr data[0], n - i)
if j < data.len:
break
i += j
proc myEof(user: pointer): cint {.cdecl.} =
return cint(stdin.endOfFile())
type stbi_write_func = proc(context, data: pointer; size: cint) {.cdecl.}
proc stbi_write_png_to_func(fun: stbi_write_func; context: pointer;
w, h, comp: cint; data: pointer; stride_in_bytes: cint) {.importc.}
proc stbi_write_bmp_to_func(fun: stbi_write_func; context: pointer;
w, h, comp: cint; data: pointer) {.importc.}
proc stbi_write_jpg_to_func(fun: stbi_write_func; context: pointer;
w, h, comp: cint; data: pointer; quality: cint) {.importc.}
proc myWriteFunc(context, data: pointer; size: cint) {.cdecl.} =
discard stdout.writeBuffer(data, size)
proc main() =
enterNetworkSandbox()
let scheme = getEnv("MAPPED_URI_SCHEME")
let f = scheme.after('+')
case getEnv("MAPPED_URI_PATH")
of "decode":
if f notin ["jpeg", "gif", "bmp", "png"]:
stdout.write("Cha-Control: ConnectionError 1 unknown format " & f)
var x: cint
var y: cint
var channels_in_file: cint
var clbk = stbi_io_callbacks(
read: myRead,
skip: mySkip,
eof: myEof
)
let p = stbi_load_from_callbacks(addr clbk, nil, x, y, channels_in_file, 4)
if p == nil:
stdout.write("Cha-Control: ConnectionError 1 stbi error " &
$stbi_failure_reason())
return
stdout.write("Cha-Image-Dimensions: " & $x & "x" & $y & "\n\n")
discard stdout.writeBuffer(p, x * y * 4)
stbi_image_free(p)
of "encode":
let headers = getEnv("REQUEST_HEADERS")
var quality = cint(50)
var width = cint(0)
var height = cint(0)
for hdr in headers.split('\n'):
case hdr.until(':')
of "Cha-Image-Dimensions":
let s = hdr.after(':').strip().split('x')
#TODO error handling
let w = parseUInt32(s[0], allowSign = false)
let h = parseUInt32(s[1], allowSign = false)
if w.isNone or w.isNone:
stdout.write("Cha-Control: ConnectionError 1 wrong dimensions")
return
width = cint(w.get)
height = cint(h.get)
of "Cha-Image-Quality":
let s = hdr.after(':').strip()
let q = parseUInt32(s, allowSign = false).get(101)
if q < 1 or 100 < q:
stdout.write("Cha-Control: ConnectionError 1 wrong quality")
return
quality = cint(q)
let s = stdin.readAll()
if s.len != width * height * 4:
stdout.write("Cha-Control: ConnectionError 1 wrong size")
return
stdout.write("Cha-Image-Dimensions: " & $width & 'x' & $height & "\n\n")
let p = unsafeAddr s[0]
case f
of "png":
stbi_write_png_to_func(myWriteFunc, nil, cint(width), cint(height), 4, p,
0)
of "bmp":
stbi_write_bmp_to_func(myWriteFunc, nil, cint(width), cint(height), 4, p)
of "jpeg":
stbi_write_jpg_to_func(myWriteFunc, nil, cint(width), cint(height), 4, p,
quality)
else:
stdout.write("Cha-Control: ConnectionError 1 unknown format " & f)
main()
|