From 9636425fa0a941f6f92e906b0e578b9869b3d043 Mon Sep 17 00:00:00 2001
From: Timo Kokkonen <timo.t.kokkonen@iki.fi>
Date: Sun, 6 Oct 2013 18:26:14 +0300
Subject: [PATCH] main: Open ouput file when one is requested

Write the read data into a given logfile and not only into stdout.

Signed-off-by: Timo Kokkonen <timo.t.kokkonen@iki.fi>
---
 main.c | 26 ++++++++++++++++++++++----
 1 file changed, 22 insertions(+), 4 deletions(-)

diff --git a/main.c b/main.c
index 065d9dc..9ac44f9 100644
--- a/main.c
+++ b/main.c
@@ -1,6 +1,9 @@
 #include <stdio.h>
 #include <unistd.h>
+#include <fcntl.h>
 #include <sys/epoll.h>
+#include <sys/types.h>
+#include <sys/stat.h>
 
 #include "options.h"
 #include "baud.h"
@@ -10,7 +13,7 @@ int main(int argc, char *argv[])
 {
 	struct epoll_event ev;
 	struct plotter_options options;
-	int fd, baud, ret;
+	int fd, baud, ret, out_fd = STDOUT_FILENO;
 	int epoll_fd;
 	char buf[256];
 
@@ -26,8 +29,22 @@ int main(int argc, char *argv[])
 	if (baud != options.baud_rate) {
 		pr_err("Failed to set baudrate to %d, only got %d\n",
 			options.baud_rate, baud);
-		close(fd);
-		return 1;
+		ret = 1;
+		goto out;
+	}
+
+	if (options.output_path) {
+		pr_debug("Opening %s for writing the log file\n",
+			options.output_path);
+
+		out_fd = open(options.output_path,
+			O_CREAT | O_APPEND | O_WRONLY, 0664);
+		if (out_fd < 0) {
+			pr_err("Failed to open file %s for writing: %m\n",
+				options.output_path);
+			ret = 1;
+			goto out;
+		}
 	}
 
 	epoll_fd = epoll_create(1);
@@ -67,6 +84,7 @@ int main(int argc, char *argv[])
 		}
 	}
 
+out:
 	close(fd);
-	return 0;
+	return ret;
 }
-- 
2.44.0