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returned back to more golang style
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@a-mr
a-mr committed Feb 12, 2020
1 parent 5838315 commit 6a082e2
Showing 1 changed file with 79 additions and 73 deletions.
152 changes: 79 additions & 73 deletions lib/pure/os.nim
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Original file line number Diff line number Diff line change
Expand Up @@ -2096,86 +2096,92 @@ iterator walkDir*(dir: string; relative=false): tuple[kind: PathComponent, path:
yield (k, y)

type
WalkStepKind* = enum ## status of the step of walking through directory.
## Due to differences between operating systems,
## opening directory status may not have exactly
## the same meaning.
wsDirFailure, ## opening directory error: unrecognized OS-specific
wsDirNotFound, ## opening directory error: no such path
wsDirNoAccess, ## opening directory error: access denied a.k.a.
## permission denied error for the specified path
## (may have happened at its parent directory on posix)
wsNotDir, ## opening directory error: not a directory
## (a normal file with the same path exists)
wsDirOpened, ## opening directory OK, the directory can be read
wsEntryOk, ## entry OK: path component is right
wsEntryBad ## entry error: a broken symlink (on posix), where it's
## unclear if it points to a file or directory
wsInterrupted ## reading directory entries was interrupted
WalkStep* = object ## step of walking through directory
path*: string ## the path that this step applies to
code*: OSErrorCode ## OS error code for the step
case kind*: WalkStepKind ## discriminator
of wsEntryOk:
entryType*: PathComponent ## path component
of wsDirFailure, wsDirNoAccess, wsDirNotFound, wsNotDir,
wsDirOpened, wsEntryBad, wsInterrupted:
discard

iterator tryWalkDir*(dir: string, relative=false): WalkStep {.
WalkStatus* = enum ## status of the step of walking through directory;
## due to differences between operating systems,
## opening directory status may not have exactly
## the same meaning.
wsOpenUnknown, ## opening directory error: unrecognized OS-specific one
wsOpenOk, ## opening directory OK, the directory can be read
wsOpenNotFound, ## opening directory error: no such path
wsOpenNoAccess, ## opening directory error: access denied a.k.a.
## permission denied error for the specified path
## (may have happened at its parent directory on posix)
wsOpenNotDir, ## opening directory error: not a directory
## (a normal file with the same path exists)
wsEntryOk, ## entry OK: path component is correct
wsEntryBad ## entry error: a broken symlink (on posix), where it's
## unclear if it points to a file or directory
wsInterrupted ## reading directory entries was interrupted

iterator tryWalkDir*(dir: string, relative=false):
tuple[status: WalkStatus, kind: PathComponent, path: string,
code: OSErrorCode] {.
tags: [ReadDirEffect], raises: [], noNimScript, since: (1, 1).} =
## Walks over the directory `dir` and yields *steps* for each
## directory or file in `dir`, non-recursively. It's a version of
## `walkDir iterator <#walkDir.i,string>`_ with more thorough error
## checking. Never raises an exception.
##
## Each step is object variant ``WalkStep``, which contains corresponding
## path ``path``, OS error code ``code`` and discriminator ``kind``:
## Each step is a tuple, which contains ``status: WalkStatus``,
## path ``path``, entry type ``kind: PathCompenent``, OS error code ``code``.
##
## - it yields open directory status once after opening
## - it yields open directory status **once** after opening
## (when `relative=true` the path is '.'),
## ``kind`` is one of ``wsDirOpened``, ``wsDirNoAccess``,
## ``wsDirNotFound``, ``wsNotDir``, ``wsDirFailure``
## - then it yields zero or more entries, each can be of the following kind:
## - ``kind=wsEntryOk``: signifies normal entries with
## path component ``entryType``
## - ``kind=wsEntryBad``: broken symlink (without path component)
## - ``kind=wsInterrupted``: signifies that a rare OS-specific I/O error
## ``status`` is one of ``wsOpenOk``, ``wsOpenNoAccess``,
## ``wsOpenNotFound``, ``wsOpenNotDir``, ``wsOpenUnknown``
## - then it yields zero or more entries, each can be of the following type:
## - ``status=wsEntryOk``: signifies normal entries with
## path component ``kind``
## - ``status=wsEntryBad``: broken symlink (without path component)
## - ``status=wsInterrupted``: signifies that a rare OS-specific I/O error
## happenned and the walking was terminated.
##
## An example of usage with just minimal error logging:
## Path component ``kind`` is only meaningful when ``status=wsEntryOk``.
##
## An example of usage with just a minimal error logging:
## .. code-block:: Nim
## for status, kind, path, code in tryWalkDir("dirA"):
## case status
## of wsOpenOk: discard
## of wsEntryOk: echo path & " is entry of kind " & $kind
## else: echo "got error " & osErrorMsg(code) & " on " & path
##
## To just check whether the directory can be opened or not :
## .. code-block:: Nim
## for step in tryWalkDir("dirA"):
## case step.kind
## of wsDirOpened: discard
## of wsEntryOk: echo step.path & " is entry of kind " & $step.entryType
## else: echo "got error " & osErrorMsg(step.code) & " on " & step.path
## proc tryOpenDir(dir: string): WalkStatus =
## for status, _, _, _ in tryWalkDir(dir):
## case status
## of wsOpenOk, wsOpenUnknown, wsOpenNoAccess, wsOpenNotFound, wsOpenNotDir:
## return status
## else: continue # can not happen
## echo "can be opened: ", tryOpenDir("dirA") == wsOpenOk
##
## Iterator ``walkDir`` itself may be implemented using tryWalkDir:
## .. code-block:: Nim
## iterator myWalkDir(path: string, relative: bool):
## tuple[kind: PathComponent, path: string] =
## for step in tryWalkDir(path, relative):
## case step.kind
## of wsDirOpened, wsDirNotFound,
## wsDirNoAccess, wsDirNoAccess, wsNotDir: discard
## of wsEntryOk: yield (step.entryType, step.path)
## of wsEntryBad: yield (pcLinkToFile, step.path)
## of wsInterrupted: raiseOSError(step.code)

var step: WalkStep
## for (status, kind, path, code) in tryWalkDir(path, relative):
## case status
## of wsOpenOk, wsOpenNotFound,
## wsOpenUnknown, wsOpenNoAccess, wsOpenNotDir: discard
## of wsEntryOk: yield (kind, path)
## of wsEntryBad: yield (pcLinkToFile, path)
## of wsInterrupted: raiseOSError(code)

var step: tuple[status: WalkStatus, kind: PathComponent,
path: string, code: OSErrorCode]
var skip = false
let outDir = if relative: "." else: dir
proc openStatus(s: WalkStepKind, path: string): WalkStep =
let code = if s == wsDirOpened: OSErrorCode(0) else: osLastError()
result = WalkStep(kind: s, code: code, path: path)
proc entryOk(pc: PathComponent, path: string): WalkStep =
WalkStep(kind: wsEntryOk, entryType: pc, code: OSErrorCode(0), path: path)
proc entryError(k: WalkStepKind, path: string): WalkStep =
WalkStep(kind: k, code: osLastError(), path: path)
template openStatus(s, p): auto =
let code = if s == wsOpenOk: OSErrorCode(0) else: osLastError()
(status: s, kind: pcDir, path: p, code: code)
template entryOk(pc, p): auto =
(status: wsEntryOk, kind: pc, path: p, code: OSErrorCode(0))
template entryError(s, p): auto =
(status: s, kind: pcLinkToFile, path: p, code: osLastError())

when defined(windows):
template resolveFile(fdat: WIN32_FIND_DATA, relative: bool): WalkStep =
template resolveFile(fdat: WIN32_FIND_DATA, relative: bool): auto =
var k: PathComponent
if (fdat.dwFileAttributes and FILE_ATTRIBUTE_DIRECTORY) != 0'i32:
k = pcDir
Expand All @@ -2192,20 +2198,20 @@ iterator tryWalkDir*(dir: string, relative=false): WalkStep {.
findClose(h)
let status =
if h != -1:
wsDirOpened
wsOpenOk
else:
case getLastError()
of ERROR_PATH_NOT_FOUND: wsDirNotFound
of ERROR_DIRECTORY: wsNotDir
of ERROR_ACCESS_DENIED: wsDirNoAccess
else: wsDirFailure
of ERROR_PATH_NOT_FOUND: wsOpenNotFound
of ERROR_DIRECTORY: wsOpenNotDir
of ERROR_ACCESS_DENIED: wsOpenNoAccess
else: wsOpenUnknown
step = openStatus(status, outDir)

var firstStep = true
while true:
if not skip:
yield step
if h == -1 or step.kind == wsInterrupted:
if h == -1 or step.status == wsInterrupted:
break
if firstStep: # use file obtained by findFirstFile
firstStep = false
Expand All @@ -2225,7 +2231,7 @@ iterator tryWalkDir*(dir: string, relative=false): WalkStep {.
skip = false
step = entryError(wsInterrupted, outDir)
else:
proc resolveFile(x: ptr Dirent, path: string, y: string): WalkStep =
proc resolveFile(x: ptr Dirent, path: string, y: string): auto =
var k = pcFile
when defined(linux) or defined(macosx) or
defined(bsd) or defined(genode) or defined(nintendoswitch):
Expand Down Expand Up @@ -2267,18 +2273,18 @@ iterator tryWalkDir*(dir: string, relative=false): WalkStep {.
discard closedir(d)
let status =
if d != nil:
wsDirOpened
wsOpenOk
else:
if errno == ENOENT: wsDirNotFound
elif errno == ENOTDIR: wsNotDir
elif errno == EACCES: wsDirNoAccess
else: wsDirFailure
if errno == ENOENT: wsOpenNotFound
elif errno == ENOTDIR: wsOpenNotDir
elif errno == EACCES: wsOpenNoAccess
else: wsOpenUnknown
step = openStatus(status, outDir)

while true:
if not skip:
yield step
if d == nil or step.kind == wsInterrupted:
if d == nil or step.status == wsInterrupted:
break
let errnoSave = errno
errno = 0
Expand Down

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