From: Ben Harris <bjh21@bjh21.me.uk>
Date: Sun, 11 Nov 2018 18:24:37 +0000 (+0000)
Subject: Implement reading from state file.
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~bjharris/git?a=commitdiff_plain;h=0b03b7d584e6bdcf601ba735d079bdc07ee87399;p=clunk.git

Implement reading from state file.
---

diff --git a/clunk.c b/clunk.c
index 0ca065a..cbb8efb 100644
--- a/clunk.c
+++ b/clunk.c
@@ -80,6 +80,30 @@ pulse()
 	dummy_out(false);
 }
 
+static void
+init_statestring(char const *str)
+{
+	if (sscanf(str, "%d:%d:%d", &displayed.tm_hour,
+		   &displayed.tm_min, &displayed.tm_sec) != 3)
+		errx(1, "usage");
+}
+
+static void
+init_statefile(char const *statefilename)
+{
+	char buf[10];
+	ssize_t len;
+
+	statefd = open(optarg, O_RDWR | O_CREAT | O_DSYNC, 0666);
+	if (statefd == -1)
+		err(1, "%s", optarg);
+	len = pread(statefd, buf, 9, 0);
+	if (len == -1)
+		err(1, "read %s", optarg);
+	buf[len] = '\0';
+	init_statestring(buf);
+}
+
 static void
 init(int argc, char **argv)
 {
@@ -95,15 +119,10 @@ init(int argc, char **argv)
 	while ((opt = getopt(argc, argv, "f:s:")) != -1) {
 		switch (opt) {
 		case 'f':
-			statefd =
-				open(optarg, O_RDWR | O_CREAT | O_DSYNC, 0666);
-			if (statefd == -1)
-				err(1, "%s", optarg);
+			init_statefile(optarg);
 			break;
 		case 's':
-			if (sscanf(optarg, "%d:%d:%d", &displayed.tm_hour,
-				   &displayed.tm_min, &displayed.tm_sec) != 3)
-				errx(1, "usage");
+			init_statestring(optarg);
 			break;
 		}
 	}