diff options
Diffstat (limited to 'lib/pure/streams.nim')
| -rwxr-xr-x | lib/pure/streams.nim | 114 |
1 files changed, 89 insertions, 25 deletions
diff --git a/lib/pure/streams.nim b/lib/pure/streams.nim index dc76bd95f..5e8926e6d 100755 --- a/lib/pure/streams.nim +++ b/lib/pure/streams.nim @@ -19,13 +19,75 @@ proc newEIO(msg: string): ref EIO = type PStream* = ref TStream TStream* = object of TObject ## Stream interface that supports - ## writing or reading. - close*: proc (s: PStream) - atEnd*: proc (s: PStream): bool - setPosition*: proc (s: PStream, pos: int) - getPosition*: proc (s: PStream): int - readData*: proc (s: PStream, buffer: pointer, bufLen: int): int - writeData*: proc (s: PStream, buffer: pointer, bufLen: int) + ## writing or reading. Note that these fields + ## here shouldn't be used directly. They are + ## accessible so that a stream implementation + ## can override them. + closeImpl*: proc (s: PStream) + atEndImpl*: proc (s: PStream): bool + setPositionImpl*: proc (s: PStream, pos: int) + getPositionImpl*: proc (s: PStream): int + readDataImpl*: proc (s: PStream, buffer: pointer, bufLen: int): int + writeDataImpl*: proc (s: PStream, buffer: pointer, bufLen: int) + flushImpl*: proc (s: PStream) + +proc flush*(s: PStream) = + ## flushes the buffers that the stream `s` might use. + if not isNil(s.flushImpl): s.flushImpl(s) + +proc close*(s: PStream) = + ## closes the stream `s`. + if not isNil(s.closeImpl): s.closeImpl(s) + +proc close*(s, unused: PStream) {.deprecated.} = + ## closes the stream `s`. + s.closeImpl(s) + +proc atEnd*(s: PStream): bool = + ## checks if more data can be read from `f`. Returns true if all data has + ## been read. + result = s.atEndImpl(s) + +proc atEnd*(s, unused: PStream): bool {.deprecated.} = + ## checks if more data can be read from `f`. Returns true if all data has + ## been read. + result = s.atEndImpl(s) + +proc setPosition*(s: PStream, pos: int) = + ## sets the position `pos` of the stream `s`. + s.setPositionImpl(s, pos) + +proc setPosition*(s, unused: PStream, pos: int) {.deprecated.} = + ## sets the position `pos` of the stream `s`. + s.setPositionImpl(s, pos) + +proc getPosition*(s: PStream): int = + ## retrieves the current position in the stream `s`. + result = s.getPositionImpl(s) + +proc getPosition*(s, unused: PStream): int {.deprecated.} = + ## retrieves the current position in the stream `s`. + result = s.getPositionImpl(s) + +proc readData*(s: PStream, buffer: pointer, bufLen: int): int = + ## low level proc that reads data into an untyped `buffer` of `bufLen` size. + result = s.readDataImpl(s, buffer, bufLen) + +proc readData*(s, unused: PStream, buffer: pointer, + bufLen: int): int {.deprecated.} = + ## low level proc that reads data into an untyped `buffer` of `bufLen` size. + result = s.readDataImpl(s, buffer, bufLen) + +proc writeData*(s: PStream, buffer: pointer, bufLen: int) = + ## low level proc that writes an untyped `buffer` of `bufLen` size + ## to the stream `s`. + s.writeDataImpl(s, buffer, bufLen) + +proc writeData*(s, unused: PStream, buffer: pointer, + bufLen: int) {.deprecated.} = + ## low level proc that writes an untyped `buffer` of `bufLen` size + ## to the stream `s`. + s.writeDataImpl(s, buffer, bufLen) proc write*[T](s: PStream, x: T) = ## generic write procedure. Writes `x` to the stream `s`. Implementation: @@ -35,22 +97,22 @@ proc write*[T](s: PStream, x: T) = ## s.writeData(s, addr(x), sizeof(x)) var y: T shallowCopy(y, x) - s.writeData(s, addr(y), sizeof(y)) + writeData(s, addr(y), sizeof(y)) proc write*(s: PStream, x: string) = ## writes the string `x` to the the stream `s`. No length field or ## terminating zero is written. - s.writeData(s, cstring(x), x.len) + writeData(s, cstring(x), x.len) proc read[T](s: PStream, result: var T) = ## generic read procedure. Reads `result` from the stream `s`. - if s.readData(s, addr(result), sizeof(T)) != sizeof(T): + if readData(s, addr(result), sizeof(T)) != sizeof(T): raise newEIO("cannot read from stream") proc readChar*(s: PStream): char = ## reads a char from the stream `s`. Raises `EIO` if an error occured. ## Returns '\0' as an EOF marker. - discard s.readData(s, addr(result), sizeof(result)) + discard readData(s, addr(result), sizeof(result)) proc readBool*(s: PStream): bool = ## reads a bool from the stream `s`. Raises `EIO` if an error occured. @@ -84,14 +146,14 @@ proc readStr*(s: PStream, length: int): TaintedString = ## reads a string of length `length` from the stream `s`. Raises `EIO` if ## an error occured. result = newString(length).TaintedString - var L = s.readData(s, addr(string(result)[0]), length) + var L = readData(s, addr(string(result)[0]), length) if L != length: setLen(result.string, L) proc readLine*(s: PStream): TaintedString = ## Reads a line from a stream `s`. Note: This is not very efficient. Raises ## `EIO` if an error occured. result = TaintedString"" - while not s.atEnd(s): + while not atEnd(s): var c = readChar(s) if c == '\c': c = readChar(s) @@ -140,12 +202,12 @@ proc newStringStream*(s: string = ""): PStringStream = new(result) result.data = s result.pos = 0 - result.close = ssClose - result.atEnd = ssAtEnd - result.setPosition = ssSetPosition - result.getPosition = ssGetPosition - result.readData = ssReadData - result.writeData = ssWriteData + result.closeImpl = ssClose + result.atEndImpl = ssAtEnd + result.setPositionImpl = ssSetPosition + result.getPositionImpl = ssGetPosition + result.readDataImpl = ssReadData + result.writeDataImpl = ssWriteData type PFileStream* = ref TFileStream ## a stream that encapsulates a `TFile` @@ -153,6 +215,7 @@ type f: TFile proc fsClose(s: PStream) = close(PFileStream(s).f) +proc fsFlush(s: PStream) = flushFile(PFileStream(s).f) proc fsAtEnd(s: PStream): bool = return EndOfFile(PFileStream(s).f) proc fsSetPosition(s: PStream, pos: int) = setFilePos(PFileStream(s).f, pos) proc fsGetPosition(s: PStream): int = return int(getFilePos(PFileStream(s).f)) @@ -168,12 +231,13 @@ proc newFileStream*(f: TFile): PFileStream = ## creates a new stream from the file `f`. new(result) result.f = f - result.close = fsClose - result.atEnd = fsAtEnd - result.setPosition = fsSetPosition - result.getPosition = fsGetPosition - result.readData = fsReadData - result.writeData = fsWriteData + result.closeImpl = fsClose + result.atEndImpl = fsAtEnd + result.setPositionImpl = fsSetPosition + result.getPositionImpl = fsGetPosition + result.readDataImpl = fsReadData + result.writeDataImpl = fsWriteData + result.flushImpl = fsFlush proc newFileStream*(filename: string, mode: TFileMode): PFileStream = ## creates a new stream from the file named `filename` with the mode `mode`. |