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author | Andy Wingo <wingo@pobox.com> | 2011-06-16 20:01:56 +0200 |
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committer | Andy Wingo <wingo@pobox.com> | 2011-06-16 20:01:56 +0200 |
commit | 99cc1092a89292c6e6db2db537988e5963b19868 (patch) | |
tree | 94f69d35c6328c2ab83304d8996a2dd957cac529 /lib/fclose.c | |
parent | 46da7909e1f67c13284730344e971d293df890c0 (diff) | |
parent | 32f94bf258bd032fa6f96fc76e4153086bc001f5 (diff) | |
download | guile-99cc1092a89292c6e6db2db537988e5963b19868.tar.gz |
Merge remote-tracking branch 'local-2.0/stable-2.0'
Diffstat (limited to 'lib/fclose.c')
-rw-r--r-- | lib/fclose.c | 49 |
1 files changed, 43 insertions, 6 deletions
diff --git a/lib/fclose.c b/lib/fclose.c index 805449a20..a4a519f7c 100644 --- a/lib/fclose.c +++ b/lib/fclose.c @@ -22,26 +22,63 @@ #include <errno.h> #include <unistd.h> -/* Override fclose() to call the overridden close(). */ +#include "freading.h" + +/* Override fclose() to call the overridden fflush() or close(). */ int rpl_fclose (FILE *fp) #undef fclose { int saved_errno = 0; + int fd; + int result = 0; + + /* Don't change behavior on memstreams. */ + fd = fileno (fp); + if (fd < 0) + return fclose (fp); - if (fflush (fp)) + /* We only need to flush the file if it is not reading or if it is + seekable. This only guarantees the file position of input files + if the fflush module is also in use. */ + if ((!freading (fp) || lseek (fileno (fp), 0, SEEK_CUR) != -1) + && fflush (fp)) saved_errno = errno; - if (close (fileno (fp)) < 0 && saved_errno == 0) + /* fclose() calls close(), but we need to also invoke all hooks that our + overridden close() function invokes. See lib/close.c. */ +#if WINDOWS_SOCKETS + /* Call the overridden close(), then the original fclose(). + Note about multithread-safety: There is a race condition where some + other thread could open fd between our close and fclose. */ + if (close (fd) < 0 && saved_errno == 0) saved_errno = errno; - fclose (fp); /* will fail with errno = EBADF */ + fclose (fp); /* will fail with errno = EBADF, if we did not lose a race */ + +#else /* !WINDOWS_SOCKETS */ + /* Call fclose() and invoke all hooks of the overridden close(). */ + +# if REPLACE_FCHDIR + /* Note about multithread-safety: There is a race condition here as well. + Some other thread could open fd between our calls to fclose and + _gl_unregister_fd. */ + result = fclose (fp); + if (result == 0) + _gl_unregister_fd (fd); +# else + /* No race condition here. */ + result = fclose (fp); +# endif + +#endif /* !WINDOWS_SOCKETS */ if (saved_errno != 0) { errno = saved_errno; - return EOF; + result = EOF; } - return 0; + + return result; } |