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import std/options
import std/os
import std/posix
import std/strutils
import utils/sandbox
import utils/twtstr
{.passc: "-fno-strict-aliasing".}
{.passl: "-fno-strict-aliasing".}
{.compile("stb_image.c", "-O3").}
{.push header: "stb_image.h".}
type stbi_io_callbacks {.importc.} = object
read: proc(user: pointer; data: ptr char; 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 uint8 {.importc.}
proc stbi_info_from_callbacks(clbk: ptr stbi_io_callbacks; user: pointer;
x, y, comp: var cint): cint {.importc.}
proc stbi_failure_reason(): cstring {.importc.}
proc stbi_image_free(retval_from_stbi_load: pointer) {.importc.}
{.pop.}
type StbiUser = object
atEof: bool
const STDIN_FILENO = 0
const STDOUT_FILENO = 1
proc myRead(user: pointer; data: ptr char; size: cint): cint {.cdecl.} =
var n = cint(0)
while n < size:
let i = read(STDIN_FILENO, addr cast[ptr UncheckedArray[char]](data)[n],
int(size - n))
if i == 0:
cast[ptr StbiUser](user)[].atEof = true
break
n += cint(i)
return n
proc mySkip(user: pointer; size: cint) {.cdecl.} =
var data: array[4096, uint8]
var n = cint(0)
while n < size:
let i = read(STDIN_FILENO, addr data[0], min(int(size - n), data.len))
if i == 0:
cast[ptr StbiUser](user)[].atEof = true
break
n += cint(i)
proc myEof(user: pointer): cint {.cdecl.} =
return cint(cast[ptr StbiUser](user)[].atEof)
type stbi_write_func = proc(context, data: pointer; size: cint) {.cdecl.}
{.push header: "stb_image_write.h".}
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.}
{.pop.}
proc writeAll(data: pointer; size: int) =
var n = 0
while n < size:
let i = write(STDOUT_FILENO, addr cast[ptr UncheckedArray[uint8]](data)[n],
int(size) - n)
assert i >= 0
n += i
proc myWriteFunc(context, data: pointer; size: cint) {.cdecl.} =
writeAll(data, int(size))
{.push header: "stb_image_resize.h".}
proc stbir_resize_uint8(input_pixels: ptr uint8;
input_w, input_h, input_stride_in_bytes: cint; output_pixels: ptr uint8;
output_w, output_h, output_stride_in_bytes, num_channels: cint): cint
{.importc.}
{.pop.}
proc puts(s: string) =
if s.len > 0:
writeAll(unsafeAddr s[0], s.len)
proc die(s: string) {.noreturn.} =
puts(s)
quit(1)
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", "x-unknown"]:
die("Cha-Control: ConnectionError 1 unknown format " & f)
var user = StbiUser()
var x: cint
var y: cint
var channels_in_file: cint
var clbk = stbi_io_callbacks(
read: myRead,
skip: mySkip,
eof: myEof
)
let headers = getEnv("REQUEST_HEADERS")
var targetWidth = cint(-1)
var targetHeight = cint(-1)
var infoOnly = false
for hdr in headers.split('\n'):
let v = hdr.after(':').strip()
case hdr.until(':')
of "Cha-Image-Info-Only":
infoOnly = v == "1"
of "Cha-Image-Target-Dimensions":
let s = v.split('x')
if s.len != 2:
die("Cha-Control: ConnectionError 1 wrong dimensions\n")
let w = parseUInt32(s[0], allowSign = false)
let h = parseUInt32(s[1], allowSign = false)
if w.isNone or w.isNone:
die("Cha-Control: ConnectionError 1 wrong dimensions\n")
targetWidth = cint(w.get)
targetHeight = cint(h.get)
if infoOnly:
if stbi_info_from_callbacks(addr clbk, addr user, x, y,
channels_in_file) == 1:
puts("Cha-Image-Dimensions: " & $x & "x" & $y & "\n\n")
quit(0)
else:
die("Cha-Control: ConnectionError 1 stbi error " &
$stbi_failure_reason())
let p = stbi_load_from_callbacks(addr clbk, addr user, x, y,
channels_in_file, 4)
if p == nil:
die("Cha-Control: ConnectionError 1 stbi error " &
$stbi_failure_reason())
elif targetWidth != -1 and targetHeight != -1:
let hdr = "Cha-Image-Dimensions: " & $targetWidth & "x" &
$targetHeight & "\n\n"
let p2 = cast[ptr UncheckedArray[uint8]](alloc(hdr.len +
targetWidth * targetHeight * 4))
copyMem(addr p2[0], unsafeAddr hdr[0], hdr.len)
doAssert stbir_resize_uint8(p, x, y, 0, addr p2[hdr.len], targetWidth,
targetHeight, 0, 4) == 1
writeAll(p2, hdr.len + targetWidth * targetHeight * 4)
dealloc(p2)
stbi_image_free(p)
else:
puts("Cha-Image-Dimensions: " & $x & "x" & $y & "\n\n")
writeAll(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')
let w = parseUInt32(s[0], allowSign = false)
let h = parseUInt32(s[1], allowSign = false)
if w.isNone or w.isNone:
die("Cha-Control: ConnectionError 1 wrong dimensions")
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:
die("Cha-Control: ConnectionError 1 wrong quality")
quality = cint(q)
let s = stdin.readAll()
if s.len != width * height * 4:
die("Cha-Control: ConnectionError 1 wrong size")
puts("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:
die("Cha-Control: ConnectionError 1 unknown format " & f)
main()
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