commit 4859d8d8e8a4bbaac0117db827001fae6c9062b9
author Jing Peng <pj.hades@gmail.com> Fri Mar 04 17:43:50 2022 -0500
committer Damjan Marion <dmarion@me.com> Wed Mar 23 18:52:50 2022 +0000
tree a65a02f3e4fd3c3ccc8fab58d464ee946a367272
parent 9deb2ec335925e02c4e98065b374144b9acda11a

vlib: send full error message to syslog

Currently the last character of the error message string
is temporarily changed to a null byte '\0' before the string
is sent to syslog(3), resulting in confusingly incomplete log
entries.

This patch changes the syslog format to "%.*s" so that the
maximum number of characters to be printed could be controlled.

Type: improvement

Signed-off-by: Jing Peng <pj.hades@gmail.com>
Change-Id: I1bd6295c19b51b962a3d8ee3016cd91ffb2a4eaf

src/vlib/unix/main.c

diff --git a/src/vlib/unix/main.c b/src/vlib/unix/main.c
index 8e06bfa..ba1c9d1 100644
--- a/src/vlib/unix/main.c
+++ b/src/vlib/unix/main.c
@@ -40,6 +40,7 @@
 #include <vlib/unix/unix.h>
 #include <vlib/unix/plugin.h>
 
+#include <limits.h>
 #include <signal.h>
 #include <sys/ucontext.h>
 #include <syslog.h>
@@ -247,14 +248,7 @@
     }
   else
     {
-      char save = msg[msg_len - 1];
-
-      /* Null Terminate. */
-      msg[msg_len - 1] = 0;
-
-      syslog (LOG_ERR | LOG_DAEMON, "%s", msg);
-
-      msg[msg_len - 1] = save;
+      syslog (LOG_ERR | LOG_DAEMON, "%.*s", msg_len, msg);
     }
 }
 
@@ -267,20 +261,10 @@
     return;
 
   {
-    char save;
-    u8 *msg;
-    u32 msg_len;
-
-    msg = error->what;
-    msg_len = vec_len (msg);
-
-    /* Null Terminate. */
-    save = msg[msg_len - 1];
-    msg[msg_len - 1] = 0;
-
-    syslog (LOG_ERR | LOG_DAEMON, "%s", msg);
-
-    msg[msg_len - 1] = save;
+    u8 *msg = error->what;
+    u32 len = vec_len (msg);
+    int msg_len = (len > INT_MAX) ? INT_MAX : len;
+    syslog (LOG_ERR | LOG_DAEMON, "%.*s", msg_len, msg);
   }
 }