Prevent garbage from being saved in the userid field

It seems that in some scenarios we end up with a string that isn't NUL
terminated and that results in garbage being stored as userid. This patch
is a little brute force but it fixes the problem even if a previous
version os Subsurface ended up adding other text to the end of the userid.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

3 files changed, 4 insertions, 2 deletions

diff --git a/dive.c b/dive.c
index 56c0de0ec..78ad25532 100644
--- a/dive.c
+++ b/dive.c
@@ -2720,6 +2720,8 @@ void set_save_userid_local(short value)
 void set_userid(char *rUserId)
 {
 	prefs.userid = strdup(rUserId);
+	if (strlen(prefs.userid) > 30)
+		prefs.userid[30]='\0';
 }
 
 int average_depth(struct diveplan *dive)
diff --git a/save-git.c b/save-git.c
index 288917a29..8cde454f2 100644
--- a/save-git.c
+++ b/save-git.c
@@ -754,7 +754,7 @@ static void save_userid(void *_b)
 {
 	struct membuffer *b = _b;
 	if (prefs.save_userid_local)
-		put_format(b, "userid %30s", prefs.userid);
+		put_format(b, "userid %30s\n", prefs.userid);
 }
 
 static void save_one_device(void *_b, const char *model, uint32_t deviceid,
diff --git a/save-xml.c b/save-xml.c
index cf7ccfec7..c9adf5307 100644
--- a/save-xml.c
+++ b/save-xml.c
@@ -520,7 +520,7 @@ void save_dives_buffer(struct membuffer *b, const bool select_only)
 	put_format(b, "<divelog program='subsurface' version='%d'>\n<settings>\n", VERSION);
 
 	if (prefs.save_userid_local)
-		put_format(b, "  <userid>%s</userid>\n", prefs.userid);
+		put_format(b, "  <userid>%30s</userid>\n", prefs.userid);
 
 	/* save the dive computer nicknames, if any */
 	call_for_each_dc(b, save_one_device);