X-Git-Url: http://git.itanic.dy.fi/?p=log-plotter;a=blobdiff_plain;f=main.c;h=e116477dd5d77ba2d731dde0e404ea1f888ff435;hp=6189b7be34b7048123c441f8ea1c33e96c258741;hb=3d8040b9815e450cec28cc26aa1d158fb02500ae;hpb=564f4d9d9c2cc16e53265c40ad63712cf14f534d

diff --git a/main.c b/main.c
index 6189b7b..e116477 100644
--- a/main.c
+++ b/main.c
@@ -1,6 +1,7 @@
 #include <stdio.h>
 #include <unistd.h>
 #include <fcntl.h>
+#include <string.h>
 #include <sys/epoll.h>
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -9,12 +10,67 @@
 #include "baud.h"
 #include "debug.h"
 
-int read_data(int infd, int outfd)
+/**
+ * Read data from a slow device
+ *
+ * return 1 when a complete NULL terminated line has been read
+ *
+ * return 0 when a partial line has been read and appended to the
+ *		 buffer at @offset
+ *
+ * return negative on error
+ */
+static int read_log_line(int infd, char *buf, size_t bufsize, int *offset)
+{
+	int ret;
+	int i;
+
+	ret = read(infd, buf + *offset, bufsize - *offset - 1);
+	if (read < 0) {
+		pr_err("read: %m\n");
+		return -1;
+	}
+
+	if (ret == 0) {
+		pr_err("Read EOF, stopping\n");
+		return -1;
+	}
+	buf[*offset + ret] = 0;
+
+	for (i = 0; i < ret; i++) {
+		if (buf[i + *offset] == '\n' ||
+		    buf[i + *offset] == '\r') {
+			/*
+			 * Got a complete line when there is a newline
+			 * at the end. Remove the newline and possible
+			 * other junk, such as '\r'
+			 */
+			buf[i + *offset] = 0;
+			*offset = 0;
+
+			return 1;
+		}
+
+		/*
+		 * Fixme! Nothing guarantees that there isn't actually
+		 * more data (a part of a new log entry perhaps) after
+		 * the newline. So in rare cases (we are prevented
+		 * from reading the serial line in very long time) we
+		 * might lose data from the stream..
+		 */
+	}
+
+	*offset += ret;
+	return 0;
+}
+
+static int read_data(int infd, int outfd)
 {
 	struct epoll_event ev;
 	int epoll_fd;
 	int ret;
 	char buf[256];
+	int offset;
 
 	epoll_fd = epoll_create(1);
 	if (epoll_fd < 0) {
@@ -39,22 +95,28 @@ int read_data(int infd, int outfd)
 			return -1;
 		}
 
-		ret = read(infd, buf, sizeof(buf));
-		if (read < 0) {
-			pr_err("read: %m\n");
-			break;
-		}
+		ret = read_log_line(infd, buf, sizeof(buf), &offset);
+		if (ret < 0)
+			return ret;
 
-		if (ret == 0) {
-			pr_err("Read EOF, stopping\n");
-			break;
-		}
+		if (ret == 0)
+			continue;
 
-		ret = write(outfd, buf, ret);
-		if (read < 0) {
-			pr_err("write: %m\n");
-			break;
+		if (outfd) {
+			char newline = '\n';
+			ret = write(outfd, buf, strlen(buf));
+			if (read < 0) {
+				pr_err("write: %m\n");
+				break;
+			}
+			ret = write(outfd, &newline, 1);
+			if (read < 0) {
+				pr_err("write: %m\n");
+				break;
+			}
 		}
+
+		pr_info("%s\n", buf);
 	}
 
 	return 0;
@@ -63,7 +125,7 @@ int read_data(int infd, int outfd)
 int main(int argc, char *argv[])
 {
 	struct plotter_options options;
-	int fd, baud, ret = 0, out_fd = STDOUT_FILENO;
+	int fd, baud, ret = 0, out_fd = 0;
 
 	if (read_args(argc, argv, &options))
 		return 1;