[PATCH 2/5] Detect console streams more reliably on Windows
- From
Stepan Kasal <kasal@ucw.cz>
- Date
- Jun 6, 2014, 13:42 UTC
- Message-ID
- <1402062173-9602-3-git-send-email-kasal@ucw.cz>
- In-Reply-To
- <1402062173-9602-1-git-send-email-kasal@ucw.cz>
From: Karsten Blees <blees@dcon.de>
GetStdHandle(STD_OUTPUT_HANDLE) doesn't work for stderr if stdout is redirected. Use _get_osfhandle of the FILE* instead.
_isatty() is true for all character devices (including parallel and serial ports). Check return value of GetConsoleScreenBufferInfo instead to reliably detect console handles (also don't initialize internal state from an uninitialized CONSOLE_SCREEN_BUFFER_INFO structure if the function fails).
Signed-off-by: Karsten Blees <blees@dcon.de> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Stepan Kasal <kasal@ucw.cz> --- compat/winansi.c | 50 ++++++++++++++++++++++++++------------------------ 1 file changed, 26 insertions(+), 24 deletions(-)
diff --git a/compat/winansi.c b/compat/winansi.c index abe0fea..c4be401 100644 --- a/compat/winansi.c +++ b/compat/winansi.c @@ -25,27 +25,39 @@ static HANDLE console; static WORD plain_attr; static WORD attr; static int negative; +static FILE *last_stream = NULL; -static void init(void) +static int is_console(FILE *stream) { CONSOLE_SCREEN_BUFFER_INFO sbi; + HANDLE hcon; static int initialized = 0; - if (initialized) - return; - console = GetStdHandle(STD_OUTPUT_HANDLE); - if (console == INVALID_HANDLE_VALUE) - console = NULL; + /* use cached value if stream hasn't changed */ + if (stream == last_stream) + return console != NULL; - if (!console) - return; + last_stream = stream; + console = NULL; - GetConsoleScreenBufferInfo(console, &sbi); - attr = plain_attr = sbi.wAttributes; - negative = 0; + /* get OS handle of the stream */ + hcon = (HANDLE) _get_osfhandle(_fileno(stream)); + if (hcon == INVALID_HANDLE_VALUE) + return 0; + + /* check if its a handle to a console output screen buffer */ + if (!GetConsoleScreenBufferInfo(hcon, &sbi)) + return 0; + + if (!initialized) { + attr = plain_attr = sbi.wAttributes; + negative = 0; + initialized = 1; + } - initialized = 1; + console = hcon; + return 1; } static int write_console(const char *str, size_t len) @@ -292,12 +304,7 @@ int winansi_fputs(const char *str, FILE *stream) { int rv; - if (!isatty(fileno(stream))) - return fputs(str, stream); - - init(); - - if (!console) + if (!is_console(stream)) return fputs(str, stream); rv = ansi_emulate(str, stream); @@ -315,12 +322,7 @@ int winansi_vfprintf(FILE *stream, const char *format, va_list list) char *buf = small_buf; va_list cp; - if (!isatty(fileno(stream))) - goto abort; - - init(); - - if (!console) + if (!is_console(stream)) goto abort; va_copy(cp, list);
-- 2.0.0.9635.g0be03cb -- -- *** Please reply-to-all at all times *** *** (do not pretend to know who is subscribed and who is not) *** *** Please avoid top-posting. *** The msysGit Wiki is here: https://github.com/msysgit/msysgit/wiki - Github accounts are free. You received this message because you are subscribed to the Google Groups "msysGit" group. To post to this group, send email to msysgit@googlegroups.com To unsubscribe from this group, send email to msysgit+unsubscribe@googlegroups.com For more options, and view previous threads, visit this group at http://groups.google.com/group/msysgit?hl=en_US?hl=en --- You received this message because you are subscribed to the Google Groups "msysGit" group. To unsubscribe from this group and stop receiving emails from it, send an email to msysgit+unsubscribe@googlegroups.com. For more options, visit https://groups.google.com/d/optout.