#include "pathlocks.hh"
#include "util.hh"

#include <cerrno>
#include <cstdlib>

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>


namespace nix {


int openLockFile(const Path & path, bool create)
{
    AutoCloseFD fd;

    fd = open(path.c_str(), O_RDWR | (create ? O_CREAT : 0), 0600);
    if (fd == -1 && (create || errno != ENOENT))
        throw SysError(format("opening lock file `%1%'") % path);

    closeOnExec(fd);

    return fd.borrow();
}


void deleteLockFile(const Path & path, int fd)
{
    /* Get rid of the lock file.  Have to be careful not to introduce
       races.  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, "d");
    /* Note that the result of unlink() is ignored; removing the lock
       file is an optimisation, not a necessity. */
}


bool lockFile(int fd, LockType lockType, bool wait)
{
    struct flock lock;
    if (lockType == ltRead) lock.l_type = F_RDLCK;
    else if (lockType == ltWrite) lock.l_type = F_WRLCK;
    else if (lockType == ltNone) lock.l_type = F_UNLCK;
   </td></tr></table>
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<div class='path'>path: <a href='/tracifyjs/log/?h=templatifyjs&amp;id=2850dc69fd7826817e05b524e3a6f147de537d81'>root</a>/<a href='/tracifyjs/log/package.json?h=templatifyjs&amp;id=2850dc69fd7826817e05b524e3a6f147de537d81'>package.json</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/tracifyjs/log/package.json?h=templatifyjs&amp;id=2850dc69fd7826817e05b524e3a6f147de537d81&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2015-03-29 14:02:37 +0300'>2015-03-29</span></td><td><a href='/tracifyjs/commit/package.json?h=templatifyjs&amp;id=94205c3a370d63a30fe2bd1ec844c86af042c51c'>v2.4.19</a></td><td>Mihai Bazon</td></tr>
<tr><td><span title='2015-03-29 13:15:27 +0300'>2015-03-29</span></td><td><a href='/tracifyjs/commit/package.json?h=templatifyjs&amp;id=73ca767d06bd54de07b36f934e509c42614909d1'>v2.4.18</a></td><td>Mihai Bazon</td></tr>
<tr><td><span title='2015-03-18 11:51:09 +0200'>2015-03-18</span></td><td><a href='/tracifyjs/commit/package.json?h=templatifyjs&amp;id=540c19792f813e38a815ff1bd2228ac0eca9e502'>Bump yargs version (for .array arguments)</a></td><td>Mihai Bazon</td></tr>
<tr><td><span title='2015-03-11 00:04:26 +0200'>2015-03-11</span></td><td><a href='/tracifyjs/commit/package.json?h=templatifyjs&amp;id=9de7199b88edb37753a36a9688d34a4be801f41b'>v2.4.17</a></td><td>Mihai Bazon</td></tr>
<tr><td><span title='2015-01-01 01:04:54 -0500'>2015-01-01</span></td><td><a href='/tracifyjs/commit/package.json?h=templatifyjs&amp;id=6d1c3e1aec62021c475c51f21fd553b83147218c'>Use yargs instead of optimist.</a></td><td>Kenneth Powers</td></tr>
<tr><td><span title='2014-12-09 15:21:44 +0200'>2014-12-09</span></td><td><a href='/tracifyjs/commit/package.json?h=templatifyjs&amp;id=5538ec7bd8a64c7fcc45895308a8463e4ca4d00a'>v2.4.16</a></td><td>Mihai Bazon</td></tr>
<tr><td><span title='2014-08-04 09:01:19 +0300'>2014-08-04</span></td><td><a href='/tracifyjs/commit/package.json?h=templatifyjs&amp;id=18ddf2f7b5a09e4e4da15cba4bed0e83e0d40cce'>Merge branch 'master' of https://github.com/RReverser/UglifyJS2</a></td><td>Mihai Bazon</td></tr>
<tr><td><span title='2014-08-03 20:48:59 +0300'>2014-08-03</span></td><td><a href='/tracifyjs/commit/package.json?h=templatifyjs&amp;id=b467a3c877c8a953bf945d892a5c1bdb9573336c'>Added generative testing for AST conversions.</a></td><td>Ingvar Stepanyan</td></tr>
<tr><td><span title='2014-07-28 13:49:44 -0700'>2014-07-28</span></td><td><a href='/tracifyjs/commit/package.json?h=templatifyjs&amp;id=ec3e74d7f48f2ccb4086cde60390dc58f5ddf8a2'>Added license</a></td><td>gdw2</td></tr>
<tr><td><span title='2014-07-09 18:01:40 +0300'>2014-07-09</span></td><td><a href='/tracifyjs/commit/package.json?h=templatifyjs&amp;id=83e0939088a26ad8c28bd2c1719f92bdcf17d045'>v2.4.15</a></td><td>Mihai Bazon</td></tr>
<tr><td><span title='2014-07-09 18:01:23 +0300'>2014-07-09</span></td><td><a href='/tracifyjs/commit/package.json?h=templatifyjs&amp;id=9798d96e3751d0815ec613e9bf4b7fb5e2fde041'>Lock source-map to 0.1.34</a></t