raises annotations for framed format

snappy/framing.nim

@@ -6,6 +6,8 @@ import
 export
   types
 
+{.push raises: [Defect].}
+
 {.compile: "crc32c.c".}
 # TODO: we don't have a native implementation of CRC32C algorithm yet.
 #       we can't use nimPNG CRC32
@@ -14,9 +16,11 @@ proc masked_crc32c(buf: ptr byte, len: uint): cuint {.cdecl, importc.}
 func checkCrc*(data: openArray[byte], expected: uint32): bool =
   let startPtr = if data.len == 0: nil else: data[0].unsafeAddr
   let actual = masked_crc32c(startPtr, data.len.uint)
-  result = actual == expected
+  actual == expected
 
-proc checkCrcAndAppend*(output: OutputStream, data: openArray[byte], crc: uint32): bool =
+proc checkCrcAndAppend*(
+    output: OutputStream, data: openArray[byte], crc: uint32): bool {.
+    raises: [Defect, IOError].}=
   if checkCrc(data, crc):
     output.write(data)
     return true
@@ -35,10 +39,12 @@ const
 
   STREAM_HEADER*                = "\xff\x06\x00\x00sNaPpY"
 
-proc uncompressFramedStream*(input: InputStream, output: OutputStream) {.fsMultiSync.} =
+proc uncompressFramedStream*(
+    input: InputStream, output: OutputStream) {.
+    fsMultiSync, raises: [Defect, IOError, SnappyError].} =
   try:
     if not input.readable(STREAM_HEADER.len):
-      raise newException(UnexpectedEofError, "Failed to read strean header")
+      raise newException(UnexpectedEofError, "Failed to read stream header")
 
     if input.read(STREAM_HEADER.len) != STREAM_HEADER.toOpenArrayByte(0, STREAM_HEADER.len-1):
       raise newException(MalformedSnappyData, "Invalid header value")
@@ -91,15 +97,21 @@ proc uncompressFramedStream*(input: InputStream, output: OutputStream) {.fsMulti
   finally:
     close output
 
-proc framingFormatUncompress*(input: InputStream): seq[byte] =
+proc framingFormatUncompress*(input: InputStream): seq[byte] {.
+    raises: [Defect, SnappyError].} =
   var output = memoryOutput()
-  uncompressFramedStream input, output
+  try:
+    uncompressFramedStream input, output
+  except IOError as e: raiseAssert e.msg # Doesn't happen with memory outputs
   return output.getOutput
 
-proc framingFormatUncompress*(input: openarray[byte]): seq[byte] =
+proc framingFormatUncompress*(input: openarray[byte]): seq[byte] {.
+    raises: [Defect, SnappyError].} =
   framingFormatUncompress unsafeMemoryInput(input)
 
-proc processFrame(output: OutputStream, dst: var openArray[byte], src: openArray[byte]) =
+proc processFrame(
+    output: OutputStream, dst: var openArray[byte], src: openArray[byte]) {.
+    raises: [Defect, IOError].} =
   let
     crc = masked_crc32c(src[0].unsafeAddr, src.len.uint)
     leb128 = uint32(src.len).toBytes(Leb128)
@@ -127,7 +139,8 @@ proc processFrame(output: OutputStream, dst: var openArray[byte], src: openArray
     output.write toBytesLE(crc)
     output.write dst.toOpenArray(0, encodedLen-1)
 
-proc framingFormatCompress*(output: OutputStream, src: openArray[byte]) =
+proc framingFormatCompress*(output: OutputStream, src: openArray[byte]) {.
+    raises: [Defect, IOError].} =
   const maxFrameSize = MAX_UNCOMPRESSED_DATA_LEN
   var compressedData = newSeq[byte](MAX_COMPRESSED_DATA_LEN)
 
@@ -148,5 +161,8 @@ proc framingFormatCompress*(output: OutputStream, src: openArray[byte]) =
 
 proc framingFormatCompress*(src: openArray[byte]): seq[byte] =
   var output = memoryOutput()
-  framingFormatCompress(output, src)
+  try:
+    framingFormatCompress(output, src)
+  except IOError as e: raiseAssert e.msg
+
   return output.getOutput