diff options
Diffstat (limited to 'lib/system/sysstr.nim')
| -rw-r--r-- | lib/system/sysstr.nim | 71 |
1 files changed, 46 insertions, 25 deletions
diff --git a/lib/system/sysstr.nim b/lib/system/sysstr.nim index b8dc7101d..3621c4960 100644 --- a/lib/system/sysstr.nim +++ b/lib/system/sysstr.nim @@ -47,27 +47,22 @@ else: template allocStrNoInit(size: untyped): untyped = cast[NimString](newObjNoInit(addr(strDesc), size)) -proc rawNewStringNoInit(space: int): NimString {.compilerproc.} = - var s = space - if s < 7: s = 7 +proc rawNewStringNoInit(space: int): NimString = + let s = max(space, 7) result = allocStrNoInit(sizeof(TGenericSeq) + s + 1) result.reserved = s - result.len = 0 when defined(gogc): result.elemSize = 1 proc rawNewString(space: int): NimString {.compilerproc.} = - var s = space - if s < 7: s = 7 - result = allocStr(sizeof(TGenericSeq) + s + 1) - result.reserved = s + result = rawNewStringNoInit(space) result.len = 0 - when defined(gogc): - result.elemSize = 1 + result.data[0] = '\0' proc mnewString(len: int): NimString {.compilerproc.} = - result = rawNewString(len) + result = rawNewStringNoInit(len) result.len = len + zeroMem(addr result.data[0], len + 1) proc copyStrLast(s: NimString, start, last: int): NimString {.compilerproc.} = # This is not used by most recent versions of the compiler anymore, but @@ -75,13 +70,10 @@ proc copyStrLast(s: NimString, start, last: int): NimString {.compilerproc.} = let start = max(start, 0) if s == nil: return nil let len = min(last, s.len-1) - start + 1 - if len > 0: - result = rawNewStringNoInit(len) - result.len = len - copyMem(addr(result.data), addr(s.data[start]), len) - result.data[len] = '\0' - else: - result = rawNewString(len) + result = rawNewStringNoInit(len) + result.len = len + copyMem(addr(result.data), addr(s.data[start]), len) + result.data[len] = '\0' proc copyStr(s: NimString, start: int): NimString {.compilerproc.} = # This is not used by most recent versions of the compiler anymore, but @@ -96,7 +88,8 @@ proc nimToCStringConv(s: NimString): cstring {.compilerproc, nonReloadable, inli proc toNimStr(str: cstring, len: int): NimString {.compilerproc.} = result = rawNewStringNoInit(len) result.len = len - copyMem(addr(result.data), str, len + 1) + copyMem(addr(result.data), str, len) + result.data[len] = '\0' proc cstrToNimstr(str: cstring): NimString {.compilerRtl.} = if str == nil: NimString(nil) @@ -201,7 +194,7 @@ proc addChar(s: NimString, c: char): NimString = proc resizeString(dest: NimString, addlen: int): NimString {.compilerRtl.} = if dest == nil: - result = rawNewStringNoInit(addlen) + result = rawNewString(addlen) elif dest.len + addlen <= dest.space: result = dest else: # slow path: @@ -227,15 +220,18 @@ proc appendChar(dest: NimString, c: char) {.compilerproc, inline.} = proc setLengthStr(s: NimString, newLen: int): NimString {.compilerRtl.} = let n = max(newLen, 0) if s == nil: - result = mnewString(newLen) + if n == 0: + return s + else: + result = mnewString(n) elif n <= s.space: result = s else: - let sp = max(resize(s.space), newLen) + let sp = max(resize(s.space), n) result = rawNewStringNoInit(sp) result.len = s.len - copyMem(addr result.data[0], unsafeAddr(s.data[0]), s.len+1) - zeroMem(addr result.data[s.len], newLen - s.len) + copyMem(addr result.data[0], unsafeAddr(s.data[0]), s.len) + zeroMem(addr result.data[s.len], n - s.len) result.reserved = sp result.len = n result.data[n] = '\0' @@ -308,7 +304,10 @@ proc setLengthSeqV2(s: PGenericSeq, typ: PNimType, newLen: int): PGenericSeq {. compilerRtl.} = sysAssert typ.kind == tySequence, "setLengthSeqV2: type is not a seq" if s == nil: - result = cast[PGenericSeq](newSeq(typ, newLen)) + if newLen == 0: + result = s + else: + result = cast[PGenericSeq](newSeq(typ, newLen)) else: let elemSize = typ.base.size let elemAlign = typ.base.align @@ -340,3 +339,25 @@ proc setLengthSeqV2(s: PGenericSeq, typ: PNimType, newLen: int): PGenericSeq {. result = s zeroMem(dataPointer(result, elemAlign, elemSize, result.len), (newLen-%result.len) *% elemSize) result.len = newLen + +func capacity*(self: string): int {.inline.} = + ## Returns the current capacity of the string. + # See https://github.com/nim-lang/RFCs/issues/460 + runnableExamples: + var str = newStringOfCap(cap = 42) + str.add "Nim" + assert str.capacity == 42 + + let str = cast[NimString](self) + result = if str != nil: str.space else: 0 + +func capacity*[T](self: seq[T]): int {.inline.} = + ## Returns the current capacity of the seq. + # See https://github.com/nim-lang/RFCs/issues/460 + runnableExamples: + var lst = newSeqOfCap[string](cap = 42) + lst.add "Nim" + assert lst.capacity == 42 + + let sek = cast[PGenericSeq](self) + result = if sek != nil: sek.space else: 0 |