Use manual line buffering for stdout/stderr.

This is needed for Windows where line buffering is not supported.

cmdline/mingw.c

@@ -223,11 +223,6 @@ void os_init(int opt)
 
 	exedir_init();
 
-	/* set stdout and stderr as "line buffered" */
-	/* this ensures that messages are mixed correctly */
-	setvbuf(stdout, 0, _IOLBF, BUFSIZ);
-	setvbuf(stderr, 0, _IOLBF, BUFSIZ);
-
 	last_error = 0;
 }
 

cmdline/parity.c

@@ -136,13 +136,13 @@ void parity_overflow(struct snapraid_state* state, data_off_t size)
 			if (file->blockmax > 0) {
 				if (file->blockvec[file->blockmax - 1].parity_pos >= blockalloc) {
 					msg_tag("outofparity:%s:%s\n", disk->name, esc(file->sub));
-					msg_flush();
 					if (first) {
 						first = 0;
 						msg_warning("\nYour data requires more parity than the available space.\n");
 						msg_warning("Please move the files 'outofparity' to another data disk:\n");
 					}
 					msg_warning("outofparity %s%s\n", disk->dir, file->sub);
+					msg_flush();
 				}
 			}
 		}

cmdline/state.c

@@ -930,7 +930,6 @@ void state_config(struct snapraid_state* state, const char* path, const char* co
 	}
 	if (state->filter_hidden)
 		msg_tag("filter:nohidden:\n");
-
 	msg_flush();
 }
 
@@ -4633,6 +4632,7 @@ void state_progress_end(struct snapraid_state* state, block_off_t countpos, bloc
 		if (elapsed >= 60)
 			msg_bar(" in %u:%02u", (unsigned)(elapsed / 3600), (unsigned)((elapsed % 3600) / 60));
 		msg_bar("\n");
+		msg_flush();
 	}
 }
 
@@ -4642,8 +4642,10 @@ void state_progress_stop(struct snapraid_state* state)
 
 	now = time(0);
 
-	if (!state->opt.gui)
+	if (!state->opt.gui) {
 		msg_bar("\n");
+		msg_flush();
+	}
 
 	state->progress_interruption = now;
 }
@@ -4759,7 +4761,7 @@ int state_progress(struct snapraid_state* state, block_off_t blockpos, block_off
 			if (out_eta)
 				msg_bar(", %u:%02u ETA", out_eta / 60, out_eta % 60);
 			msg_bar("%s\r", PROGRESS_CLEAR);
-			fflush(stdout);
+			msg_flush();
 		}
 
 		/* store the new measure */

cmdline/support.c

@@ -24,13 +24,22 @@
 
 int msg_level = 0;
 
+/*
+ * Note that in the following functions we always flush both
+ * stdout and stderr, because we want to ensure that they mixes
+ * well when redirected to files
+ *
+ * The buffering is similar at the "line buffered" one, that
+ * is not available on Windows, so we emulate it in this way.
+ *
+ * For stdlog the flush is only limited.
+ * To ensure flushing the caller should use msg_flush().
+ */
+
 void msg_error(const char* format, ...)
 {
 	va_list ap;
 
-	/* first output the same message to stdlog and flush it */
-	/* to avoid to mix messages in case streams are redirected */
-	/* to the same file */
 	if (stdlog) {
 		va_start(ap, format);
 		fprintf(stdlog, "msg:error: ");
@@ -41,6 +50,7 @@ void msg_error(const char* format, ...)
 
 	va_start(ap, format);
 	vfprintf(stderr, format, ap);
+	fflush(stderr);
 	va_end(ap);
 }
 
@@ -52,10 +62,12 @@ void msg_warning(const char* format, ...)
 		va_start(ap, format);
 		fprintf(stdlog, "msg:warning: ");
 		vfprintf(stdlog, format, ap);
+		fflush(stdlog);
 		va_start(ap, format);
 	} else {
 		va_start(ap, format);
 		vfprintf(stderr, format, ap);
+		fflush(stderr);
 		va_start(ap, format);
 	}
 }
@@ -75,20 +87,18 @@ void msg_status(const char* format, ...)
 {
 	va_list ap;
 
-	/* first output the same message to stdlog and flush it */
-	/* to avoid to mix messages in case streams are redirected */
-	/* to the same file */
 	if (stdlog) {
 		va_start(ap, format);
 		fprintf(stdlog, "msg:status: ");
 		vfprintf(stdlog, format, ap);
-		va_end(ap);
 		fflush(stdlog);
+		va_end(ap);
 	}
 
 	if (msg_level >= MSG_STATUS) {
 		va_start(ap, format);
 		vfprintf(stdout, format, ap);
+		fflush(stdout);
 		va_end(ap);
 	}
 }
@@ -103,6 +113,7 @@ void msg_info(const char* format, ...)
 	if (msg_level >= MSG_INFO) {
 		va_start(ap, format);
 		vfprintf(stdout, format, ap);
+		fflush(stdout);
 		va_end(ap);
 	}
 }
@@ -111,20 +122,18 @@ void msg_progress(const char* format, ...)
 {
 	va_list ap;
 
-	/* first output the same message to stdlog and flush it */
-	/* to avoid to mix messages in case streams are redirected */
-	/* to the same file */
 	if (stdlog) {
 		va_start(ap, format);
 		fprintf(stdlog, "msg:progress: ");
 		vfprintf(stdlog, format, ap);
-		va_end(ap);
 		fflush(stdlog);
+		va_end(ap);
 	}
 
 	if (msg_level >= MSG_PROGRESS) {
 		va_start(ap, format);
 		vfprintf(stdout, format, ap);
+		fflush(stdout);
 		va_end(ap);
 	}
 }
@@ -135,6 +144,7 @@ void msg_bar(const char* format, ...)
 
 	/* don't output in stdlog as these messages */
 	/* are intended for screen only */
+	/* also don't flush stdout as they are intended to be partial messages */
 
 	if (msg_level >= MSG_BAR) {
 		va_start(ap, format);
@@ -147,20 +157,18 @@ void msg_verbose(const char* format, ...)
 {
 	va_list ap;
 
-	/* first output the same message to stdlog and flush it */
-	/* to avoid to mix messages in case streams are redirected */
-	/* to the same file */
 	if (stdlog) {
 		va_start(ap, format);
 		fprintf(stdlog, "msg:verbose: ");
 		vfprintf(stdlog, format, ap);
-		va_end(ap);
 		fflush(stdlog);
+		va_end(ap);
 	}
 
 	if (msg_level >= MSG_VERBOSE) {
 		va_start(ap, format);
 		vfprintf(stdout, format, ap);
+		fflush(stdout);
 		va_end(ap);
 	}
 }
@@ -170,6 +178,7 @@ void msg_flush(void)
 	if (stdlog)
 		fflush(stdlog);
 	fflush(stdout);
+	fflush(stderr);
 }
 
 /**

cmdline/support.h

@@ -50,6 +50,8 @@ void msg_warning(const char* format, ...) __attribute__((format(attribute_printf
  * These messages neves go on the screen, but only in the log file if specified.
  *
  * Note that this function, allows not \n terminated strings.
+ *
+ * These messages are buffered. Use msg_flush() to flush them.
  */
 void msg_tag(const char* format, ...) __attribute__((format(attribute_printf, 1, 2)));
 
@@ -106,6 +108,8 @@ void msg_progress(const char* format, ...) __attribute__((format(attribute_print
  * Message that show the percentage of the progress.
  *
  * These messages never go in the log file.
+ *
+ * These messages are buffered. Use msg_flush() to flush them.
  */
 void msg_bar(const char* format, ...) __attribute__((format(attribute_printf, 1, 2)));
 

cmdline/unix.c

@@ -958,11 +958,6 @@ int devquery(tommy_list* high, tommy_list* low, int operation)
 void os_init(int opt)
 {
 	(void)opt;
-
-	/* set stdout and stderr as "line buffered" */
-	/* this ensures that messages are mixed correctly */
-	setvbuf(stdout, 0, _IOLBF, BUFSIZ);
-	setvbuf(stderr, 0, _IOLBF, BUFSIZ);
 }
 
 void os_done(void)