#
#
# Nim's Runtime Library
# (c) Copyright 2013 Andreas Rumpf
#
# See the file "copying.txt", included in this
# distribution, for details about the copyright.
#
# Nim's standard IO library. It contains high-performance
# routines for reading and writing data to (buffered) files or
# TTYs.
{.push debugger:off .} # the user does not want to trace a part
# of the standard library!
proc fputs(c: cstring, f: File) {.importc: "fputs", header: "<stdio.h>",
tags: [WriteIOEffect].}
proc fgets(c: cstring, n: int, f: File): cstring {.
importc: "fgets", header: "<stdio.h>", tags: [ReadIOEffect].}
proc fgetc(stream: File): cint {.importc: "fgetc", header: "<stdio.h>",
tags: [ReadIOEffect].}
proc ungetc(c: cint, f: File) {.importc: "ungetc", header: "<stdio.h>",
tags: [].}
proc putc(c: char, stream: File) {.importc: "putc", header: "<stdio.h>",
tags: [WriteIOEffect].}
proc fprintf(f: File, frmt: cstring) {.importc: "fprintf",
header: "<stdio.h>", varargs, tags: [WriteIOEffect].}
proc strlen(c: cstring): int {.
importc: "strlen", header: "<string.h>", tags: [].}
# C routine that is used here:
proc fread(buf: pointer, size, n: int, f: File): int {.
importc: "fread", header: "<stdio.h>", tags: [ReadIOEffect].}
proc fseek(f: File, offset: clong, whence: int): int {.
importc: "fseek", header: "<stdio.h>", tags: [].}
proc ftell(f: File): int {.importc: "ftell", header: "<stdio.h>", tags: [].}
proc setvbuf(stream: File, buf: pointer, typ, size: cint): cint {.
importc, header: "<stdio.h>", tags: [].}
{.push stackTrace:off, profiler:off.}
proc write(f: File, c: cstring) = fputs(c, f)
{.pop.}
when NoFakeVars:
when defined(windows):
const
IOFBF = cint(0)
IONBF = cint(4)
elif defined(macosx) or defined(linux):
const
IOFBF = cint(0)
IONBF = cint(2)
else:
{.error: "IOFBF not ported to your platform".}
else:
var
IOFBF {.importc: "_IOFBF", nodecl.}: cint
IONBF {.importc: "_IONBF", nodecl.}: cint
const
BufSize = 4000
proc raiseEIO(msg: string) {.noinline, noreturn.} =
sysFatal(IOError, msg)
proc readLine(f: File, line: var TaintedString): bool =
# of course this could be optimized a bit; but IO is slow anyway...
# and it was difficult to get this CORRECT with Ansi C's methods
setLen(line.string, 0) # reuse the buffer!
while true:
var c = fgetc(f)
if c < 0'i32:
if line.len > 0: break
else: return false
if c == 10'i32: break # LF
if c == 13'i32: # CR
c = fgetc(f) # is the next char LF?
if c != 10'i32: ungetc(c, f) # no, put the character back
break
add line.string, chr(int(c))
result = true
proc readLine(f: File): TaintedString =
result = TaintedString(newStringOfCap(80))
if not readLine(f, result): raiseEIO("EOF reached")
proc write(f: File, i: int) =
when sizeof(int) == 8:
fprintf(f, "%lld", i)
else:
fprintf(f, "%ld", i)
proc write(f: File, i: BiggestInt) =
when sizeof(BiggestInt) == 8:
fprintf(f, "%lld", i)
else:
fprintf(f, "%ld", i)
proc write(f: File, b: bool) =
if b: write(f, "true")
else: write(f, "false")
proc write(f: File, r: float32) = fprintf(f, "%g", r)
proc write(f: File, r: BiggestFloat) = fprintf(f, "%g", r)
proc write(f: File, c: char) = putc(c, f)
proc write(f: File, a: varargs[string, `$`]) =
for x in items(a): write(f, x)
proc readAllBuffer(file: File): string =
# This proc is for File we want to read but don't know how many
# bytes we need to read before the buffer is empty.
result = ""
var buffer = newString(BufSize)
while true:
var bytesRead = readBuffer(file, addr(buffer[0]), BufSize)
if bytesRead == BufSize:
result.add(buffer)
else:
buffer.setLen(bytesRead)
result.add(buffer)
break
proc rawFileSize(file: File): int =
# this does not raise an error opposed to `getFileSize`
var oldPos = ftell(file)
discard fseek(file, 0, 2) # seek the end of the file
result = ftell(file)
discard fseek(file, clong(oldPos), 0)
proc readAllFile(file: File, len: int): string =
# We aquire the filesize beforehand and hope it doesn't change.
# Speeds things up.
result = newString(int(len))
if readBuffer(file, addr(result[0]), int(len)) != len:
raiseEIO("error while reading from file")
proc readAllFile(file: File): string =
var len = rawFileSize(file)
result = readAllFile(file, len)
proc readAll(file: File): TaintedString =
# Separate handling needed because we need to buffer when we
# don't know the overall length of the File.
var len = rawFileSize(file)
if len >= 0:
result = readAllFile(file, len).TaintedString
else:
result = readAllBuffer(file).TaintedString
proc readFile(filename: string): TaintedString =
var f = open(filename)
try:
result = readAllFile(f).TaintedString
finally:
close(f)
proc writeFile(filename, content: string) =
var f = open(filename, fmWrite)
try:
f.write(content)
finally:
close(f)
proc endOfFile(f: File): bool =
# do not blame me; blame the ANSI C standard this is so brain-damaged
var c = fgetc(f)
ungetc(c, f)
return c < 0'i32
proc writeln[Ty](f: File, x: varargs[Ty, `$`]) =
for i in items(x): write(f, i)
write(f, "\n")
proc rawEcho(x: string) {.inline, compilerproc.} = write(stdout, x)
proc rawEchoNL() {.inline, compilerproc.} = write(stdout, "\n")
# interface to the C procs:
when (defined(windows) and not defined(useWinAnsi)) or defined(nimdoc):
include "system/widestrs"
when defined(windows) and not defined(useWinAnsi):
proc wfopen(filename, mode: WideCString): pointer {.
importc: "_wfopen", nodecl.}
proc wfreopen(filename, mode: WideCString, stream: File): File {.
importc: "_wfreopen", nodecl.}
proc fopen(filename, mode: cstring): pointer =
var f = newWideCString(filename)
var m = newWideCString(mode)
result = wfopen(f, m)
proc freopen(filename, mode: cstring, stream: File): File =
var f = newWideCString(filename)
var m = newWideCString(mode)
result = wfreopen(f, m, stream)
else:
proc fopen(filename, mode: cstring): pointer {.importc: "fopen", noDecl.}
proc freopen(filename, mode: cstring, stream: File): File {.
importc: "freopen", nodecl.}
const
FormatOpen: array [FileMode, string] = ["rb", "wb", "w+b", "r+b", "ab"]
#"rt", "wt", "w+t", "r+t", "at"
# we always use binary here as for Nim the OS line ending
# should not be translated.
proc open(f: var File, filename: string,
mode: FileMode = fmRead,
bufSize: int = -1): bool =
var p: pointer = fopen(filename, FormatOpen[mode])
result = (p != nil)
f = cast[File](p)
if bufSize > 0 and bufSize <= high(cint).int:
if setvbuf(f, nil, IOFBF, bufSize.cint) != 0'i32:
sysFatal(OutOfMemError, "out of memory")
elif bufSize == 0:
discard setvbuf(f, nil, IONBF, 0)
proc reopen(f: File, filename: string, mode: FileMode = fmRead): bool =
var p: pointer = freopen(filename, FormatOpen[mode], f)
result = p != nil
proc fdopen(filehandle: FileHandle, mode: cstring): File {.
importc: pccHack & "fdopen", header: "<stdio.h>".}
proc open(f: var File, filehandle: FileHandle, mode: FileMode): bool =
f = fdopen(filehandle, FormatOpen[mode])
result = f != nil
proc fwrite(buf: pointer, size, n: int, f: File): int {.
importc: "fwrite", noDecl.}
proc readBuffer(f: File, buffer: pointer, len: int): int =
result = fread(buffer, 1, len, f)
proc readBytes(f: File, a: var openArray[int8], start, len: int): int =
result = readBuffer(f, addr(a[start]), len)
proc readChars(f: File, a: var openArray[char], start, len: int): int =
result = readBuffer(f, addr(a[start]), len)
{.push stackTrace:off, profiler:off.}
proc writeBytes(f: File, a: openArray[int8], start, len: int): int =
var x = cast[ptr array[0..1000_000_000, int8]](a)
result = writeBuffer(f, addr(x[start]), len)
proc writeChars(f: File, a: openArray[char], start, len: int): int =
var x = cast[ptr array[0..1000_000_000, int8]](a)
result = writeBuffer(f, addr(x[start]), len)
proc writeBuffer(f: File, buffer: pointer, len: int): int =
result = fwrite(buffer, 1, len, f)
proc write(f: File, s: string) =
if writeBuffer(f, cstring(s), s.len) != s.len:
raiseEIO("cannot write string to file")
{.pop.}
proc setFilePos(f: File, pos: int64) =
if fseek(f, clong(pos), 0) != 0:
raiseEIO("cannot set file position")
proc getFilePos(f: File): int64 =
result = ftell(f)
if result < 0: raiseEIO("cannot retrieve file position")
proc getFileSize(f: File): int64 =
var oldPos = getFilePos(f)
discard fseek(f, 0, 2) # seek the end of the file
result = getFilePos(f)
setFilePos(f, oldPos)
{.pop.}