diff options
| -rw-r--r-- | include/my_sys.h | 1 | ||||
| -rw-r--r-- | mysys/my_fopen.c | 134 | ||||
| -rw-r--r-- | sql/log.cc | 74 |
3 files changed, 144 insertions, 65 deletions
diff --git a/include/my_sys.h b/include/my_sys.h index 6e2cbd4c0b3..8f7d5b0925d 100644 --- a/include/my_sys.h +++ b/include/my_sys.h @@ -631,6 +631,7 @@ extern const char** get_global_errmsgs(); extern void wait_for_free_space(const char *filename, int errors); extern FILE *my_fopen(const char *FileName,int Flags,myf MyFlags); extern FILE *my_fdopen(File Filedes,const char *name, int Flags,myf MyFlags); +extern FILE *my_freopen(const char *path, const char *mode, FILE *stream); extern int my_fclose(FILE *fd,myf MyFlags); extern File my_fileno(FILE *fd); extern int my_chsize(File fd,my_off_t newlength, int filler, myf MyFlags); diff --git a/mysys/my_fopen.c b/mysys/my_fopen.c index 861e4380690..e184c8308fc 100644 --- a/mysys/my_fopen.c +++ b/mysys/my_fopen.c @@ -18,6 +18,10 @@ #include <errno.h> #include "mysys_err.h" +#if defined(__FreeBSD__) +extern int getosreldate(void); +#endif + static void make_ftype(char * to,int flag); /* @@ -89,7 +93,135 @@ FILE *my_fopen(const char *filename, int flags, myf MyFlags) } /* my_fopen */ - /* Close a stream */ +#if defined(_WIN32) + +static FILE *my_win_freopen(const char *path, const char *mode, FILE *stream) +{ + int handle_fd, fd= _fileno(stream); + HANDLE osfh; + + DBUG_ASSERT(path && stream); + + /* Services don't have stdout/stderr on Windows, so _fileno returns -1. */ + if (fd < 0) + { + if (!freopen(path, mode, stream)) + return NULL; + + fd= _fileno(stream); + } + + if ((osfh= CreateFile(path, GENERIC_READ | GENERIC_WRITE, + FILE_SHARE_READ | FILE_SHARE_WRITE | + FILE_SHARE_DELETE, NULL, + OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, + NULL)) == INVALID_HANDLE_VALUE) + return NULL; + + if ((handle_fd= _open_osfhandle((intptr_t)osfh, + _O_APPEND | _O_TEXT)) == -1) + { + CloseHandle(osfh); + return NULL; + } + + if (_dup2(handle_fd, fd) < 0) + { + CloseHandle(osfh); + return NULL; + } + + _close(handle_fd); + + return stream; +} + +#elif defined(__FreeBSD__) + +/* No close operation hook. */ + +static int no_close(void *cookie __attribute__((unused))) +{ + return 0; +} + +/* + A hack around a race condition in the implementation of freopen. + + The race condition steams from the fact that the current fd of + the stream is closed before its number is used to duplicate the + new file descriptor. This defeats the desired atomicity of the + close and duplicate of dup2(). + + See PR number 79887 for reference: + http://www.freebsd.org/cgi/query-pr.cgi?pr=79887 +*/ + +static FILE *my_freebsd_freopen(const char *path, const char *mode, FILE *stream) +{ + int old_fd; + FILE *result; + + flockfile(stream); + + old_fd= fileno(stream); + + /* Use a no operation close hook to avoid having the fd closed. */ + stream->_close= no_close; + + /* Relies on the implicit dup2 to close old_fd. */ + result= freopen(path, mode, stream); + + /* If successful, the _close hook was replaced. */ + + if (result == NULL) + close(old_fd); + else + funlockfile(result); + + return result; +} + +#endif + + +/** + Change the file associated with a file stream. + + @param path Path to file. + @param mode Mode of the stream. + @param stream File stream. + + @note + This function is used to redirect stdout and stderr to a file and + subsequently to close and reopen that file for log rotation. + + @retval A FILE pointer on success. Otherwise, NULL. +*/ + +FILE *my_freopen(const char *path, const char *mode, FILE *stream) +{ + FILE *result; + +#if defined(_WIN32) + result= my_win_freopen(path, mode, stream); +#elif defined(__FreeBSD__) + /* + XXX: Once the fix is ported to the stable releases, this should + be dependent upon the specific FreeBSD versions. Check at: + http://www.freebsd.org/cgi/query-pr.cgi?pr=79887 + */ + if (getosreldate() > 900027) + result= freopen(path, mode, stream); + else + result= my_freebsd_freopen(path, mode, stream); +#else + result= freopen(path, mode, stream); +#endif + + return result; +} + /* Close a stream */ int my_fclose(FILE *fd, myf MyFlags) diff --git a/sql/log.cc b/sql/log.cc index b9be66f8ce7..7ab4b6b4a61 100644 --- a/sql/log.cc +++ b/sql/log.cc @@ -5686,80 +5686,26 @@ void sql_perror(const char *message) } -#ifdef __WIN__ +/* + Change the file associated with two output streams. Used to + redirect stdout and stderr to a file. The streams are reopened + only for appending (writing at end of file). +*/ extern "C" my_bool reopen_fstreams(const char *filename, FILE *outstream, FILE *errstream) { - int handle_fd; - int err_fd, out_fd; - HANDLE osfh; - - DBUG_ASSERT(filename && errstream); - - // Services don't have stdout/stderr on Windows, so _fileno returns -1. - err_fd= _fileno(errstream); - if (err_fd < 0) - { - if (!freopen(filename, "a+", errstream)) - return TRUE; - - setbuf(errstream, NULL); - err_fd= _fileno(errstream); - } - - if (outstream) - { - out_fd= _fileno(outstream); - if (out_fd < 0) - { - if (!freopen(filename, "a+", outstream)) - return TRUE; - out_fd= _fileno(outstream); - } - } - - if ((osfh= CreateFile(filename, GENERIC_READ | GENERIC_WRITE, - FILE_SHARE_READ | FILE_SHARE_WRITE | - FILE_SHARE_DELETE, NULL, - OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, - NULL)) == INVALID_HANDLE_VALUE) + if (outstream && !my_freopen(filename, "a", outstream)) return TRUE; - if ((handle_fd= _open_osfhandle((intptr_t)osfh, - _O_APPEND | _O_TEXT)) == -1) - { - CloseHandle(osfh); + if (errstream && !my_freopen(filename, "a", errstream)) return TRUE; - } - if (_dup2(handle_fd, err_fd) < 0) - { - CloseHandle(osfh); - return TRUE; - } - - if (outstream && _dup2(handle_fd, out_fd) < 0) - { - CloseHandle(osfh); - return TRUE; - } - - _close(handle_fd); - return FALSE; -} -#else -extern "C" my_bool reopen_fstreams(const char *filename, - FILE *outstream, FILE *errstream) -{ - if (outstream && !freopen(filename, "a+", outstream)) - return TRUE; - - if (errstream && !freopen(filename, "a+", errstream)) - return TRUE; + /* The error stream must be unbuffered. */ + if (errstream) + setbuf(errstream, NULL); return FALSE; } -#endif /* |