* Remove most Cygwin-specific code. Cygwin 1.7 implements advisory

POSIX locks, and simulates Unix-style file deletion semantics
  sufficiently.  Note that this means that Nix won't work on Cygwin
  1.5 anymore.

src/libstore/gc.cc

@@ -15,11 +15,6 @@
 #include <fcntl.h>
 #include <unistd.h>
 
-#ifdef __CYGWIN__
-#include <windows.h>
-#include <sys/cygwin.h>
-#endif
-
 
 namespace nix {
 
@@ -179,15 +174,6 @@ void LocalStore::addTempRoot(const Path & path)
 
             fdGCLock.close();
       
-	    /* Note that on Cygwin a lot of the following complexity
-	       is unnecessary, since we cannot delete open lock
-	       files.  If we have the lock file open, then it's valid;
-	       if we can delete it, then it wasn't in use any more. 
-
-	       Also note that on Cygwin we cannot "upgrade" a lock
-	       from a read lock to a write lock. */
-
-#ifndef __CYGWIN__
             debug(format("acquiring read lock on `%1%'") % fnTempRoots);
             lockFile(fdTempRoots, ltRead, true);
 
@@ -201,10 +187,6 @@ void LocalStore::addTempRoot(const Path & path)
             /* The garbage collector deleted this file before we could
                get a lock.  (It won't delete the file after we get a
                lock.)  Try again. */
-
-#else
-            break;
-#endif
         }
 
     }
@@ -217,14 +199,9 @@ void LocalStore::addTempRoot(const Path & path)
     string s = path + '\0';
     writeFull(fdTempRoots, (const unsigned char *) s.c_str(), s.size());
 
-#ifndef __CYGWIN__
     /* Downgrade to a read lock. */
     debug(format("downgrading to read lock on `%1%'") % fnTempRoots);
     lockFile(fdTempRoots, ltRead, true);
-#else
-    debug(format("releasing write lock on `%1%'") % fnTempRoots);
-    lockFile(fdTempRoots, ltNone, true);
-#endif
 }
 
 
@@ -252,19 +229,6 @@ static void readTempRoots(PathSet & tempRoots, FDs & fds)
         Path path = (format("%1%/%2%/%3%") % nixStateDir % tempRootsDir % *i).str();
 
         debug(format("reading temporary root file `%1%'") % path);
-
-#ifdef __CYGWIN__
-	/* On Cygwin we just try to delete the lock file. */
-	char win32Path[MAX_PATH];
-	cygwin_conv_to_full_win32_path(path.c_str(), win32Path);
-	if (DeleteFile(win32Path)) {
-            printMsg(lvlError, format("removed stale temporary roots file `%1%'")
-                % path);
-            continue;
-        } else
-            debug(format("delete of `%1%' failed: %2%") % path % GetLastError());
-#endif
-
         FDPtr fd(new AutoCloseFD(open(path.c_str(), O_RDWR, 0666)));
         if (*fd == -1) {
             /* It's okay if the file has disappeared. */
@@ -276,7 +240,6 @@ static void readTempRoots(PathSet & tempRoots, FDs & fds)
         //FDPtr fd(new AutoCloseFD(openLockFile(path, false)));
         //if (*fd == -1) continue;
 
-#ifndef __CYGWIN__
         /* Try to acquire a write lock without blocking.  This can
            only succeed if the owning process has died.  In that case
            we don't care about its temporary roots. */
@@ -287,7 +250,6 @@ static void readTempRoots(PathSet & tempRoots, FDs & fds)
             writeFull(*fd, (const unsigned char *) "d", 1);
             continue;
         }
-#endif
 
         /* Acquire a read lock.  This will prevent the owning process
            from upgrading to a write lock, therefore it will block in

src/libstore/pathlocks.cc

@@ -8,11 +8,6 @@
 #include <sys/stat.h>
 #include <fcntl.h>
 
-#ifdef __CYGWIN__
-#include <windows.h>
-#include <sys/cygwin.h>
-#endif
-
 
 namespace nix {
 
@@ -21,72 +16,24 @@ int openLockFile(const Path & path, bool create)
 {
     AutoCloseFD fd;
 
-#ifdef __CYGWIN__
-    /* On Cygwin we have to open the lock file without "DELETE"
-       sharing mode; otherwise Windows will allow open lock files to
-       be deleted (which is almost but not quite what Unix does). */
-    char win32Path[MAX_PATH + 1];
-    cygwin_conv_to_full_win32_path(path.c_str(), win32Path);
-
-    SECURITY_ATTRIBUTES sa; /* required, otherwise inexplicably bad shit happens */
-    sa.nLength = sizeof sa;
-    sa.lpSecurityDescriptor = 0;
-    sa.bInheritHandle = TRUE;
-    HANDLE h = CreateFile(win32Path, GENERIC_READ | GENERIC_WRITE,
-        FILE_SHARE_READ | FILE_SHARE_WRITE, &sa, 
-        (create ? OPEN_ALWAYS : OPEN_EXISTING), 
-        FILE_ATTRIBUTE_NORMAL, 0);
-    if (h == INVALID_HANDLE_VALUE) {
-        if (create || GetLastError() != ERROR_FILE_NOT_FOUND)
-            throw Error(format("opening lock file `%1%'") % path);
-        fd = -1;
-    }
-    else
-        fd = cygwin_attach_handle_to_fd((char *) path.c_str(), -1, h, 1, O_RDWR);
-#else        
     fd = open(path.c_str(), O_RDWR | (create ? O_CREAT : 0), 0666);
     if (fd == -1 && (create || errno != ENOENT))
         throw SysError(format("opening lock file `%1%'") % path);
-#endif
 
     return fd.borrow();
 }
 
 
-void deleteLockFilePreClose(const Path & path, int fd)
+void deleteLockFile(const Path & path, int fd)
 {
-#ifndef __CYGWIN__
     /* Get rid of the lock file.  Have to be careful not to introduce
-       races. */
+       races.  Write a (meaningless) token to the file to indicate to
-    /* On Unix, write a (meaningless) token to the file to indicate to
        other processes waiting on this lock that the lock is stale
        (deleted). */
     unlink(path.c_str());
     writeFull(fd, (const unsigned char *) "d", 1);
     /* Note that the result of unlink() is ignored; removing the lock
        file is an optimisation, not a necessity. */
-#endif
-}
-
-
-void deleteLockFilePostClose(const Path & path)
-{
-#ifdef __CYGWIN__
-    /* On Windows, just try to delete the lock file.  This will fail
-       if anybody still has the file open.  We cannot use unlink()
-       here, because Cygwin emulates Unix semantics of allowing an
-       open file to be deleted (but fakes it - the file isn't actually
-       deleted until later, so a file with the same name cannot be
-       created in the meantime). */
-    char win32Path[MAX_PATH + 1];
-    cygwin_conv_to_full_win32_path(path.c_str(), win32Path);
-    if (DeleteFile(win32Path))
-        debug(format("delete of `%1%' succeeded") % path.c_str());
-    else
-        /* Not an error: probably means that the lock is still opened
-           by someone else. */
-        debug(format("delete of `%1%' failed: %2%") % path.c_str() % GetLastError());
-#endif
 }
 
 
@@ -220,15 +167,13 @@ PathLocks::~PathLocks()
 void PathLocks::unlock()
 {
     foreach (list<FDPair>::iterator, i, fds) {
-        if (deletePaths) deleteLockFilePreClose(i->second, i->first);
+        if (deletePaths) deleteLockFile(i->second, i->first);
 
         lockedPaths.erase(i->second);
         if (close(i->first) == -1)
             printMsg(lvlError,
                 format("error (ignored): cannot close lock file on `%1%'") % i->second);
 
-	if (deletePaths) deleteLockFilePostClose(i->second);
-
         debug(format("lock released on `%1%'") % i->second);
     }
 

src/libstore/pathlocks.hh

@@ -12,10 +12,8 @@ namespace nix {
    because it doesn't exist.  Any other error throws an exception. */
 int openLockFile(const Path & path, bool create);
 
-/* Delete an open lock file.  Both must be called to be fully portable
+/* Delete an open lock file. */
-   between Unix and Windows. */
+void deleteLockFile(const Path & path, int fd);
-void deleteLockFilePreClose(const Path & path, int fd);
-void deleteLockFilePostClose(const Path & path);
 
 enum LockType { ltRead, ltWrite, ltNone };
 

src/libutil/util.cc

@@ -1,9 +1,5 @@
 #include "config.h"
 
-#ifdef __CYGWIN__
-#include <windows.h>
-#endif
-
 #include <iostream>
 #include <cerrno>
 #include <cstdio>
@@ -905,15 +901,7 @@ void closeMostFDs(const set<int> & exceptions)
 
 void quickExit(int status)
 {
-#ifdef __CYGWIN__
-    /* Hack for Cygwin: _exit() doesn't seem to work quite right,
-       since some Berkeley DB code appears to be called when a child
-       exits through _exit() (e.g., because execve() failed).  So call
-       the Windows API directly. */
-    ExitProcess(status);
-#else
     _exit(status);
-#endif
 }