refactor: Remove strncpy/STRNCPY. (#6008)

Closes #731
References #851

Note: This does not remove some intentional legacy usages of strncpy.
      - memcpy isn't equivalent because it doesn't check the string
        length of `src`, and doesn't zero-out the remainder of `dst`.
      - xstrlcpy isn't equivalent because it doesn't zero-out the
        remainder of `dst`. Some Vim logic depends on that (e.g.
        ex_append which calls vim_strnsave).

Helped-by: Douglas Schneider <ds3@ualberta.ca>
Helped-by: oni-link <knil.ino@gmail.com>
Helped-by: James McCoy <jamessan@jamessan.com>

1 files changed, 5 insertions, 6 deletions

diff --git a/src/nvim/os/env.c b/src/nvim/os/env.c
index 109b5c7175..747a34d8ce 100644
--- a/src/nvim/os/env.c
+++ b/src/nvim/os/env.c
@@ -112,11 +112,11 @@ int64_t os_get_pid(void)
 #endif
 }
 
-/// Get the hostname of the machine running Neovim.
+/// Gets the hostname of the current machine.
 ///
-/// @param hostname Buffer to store the hostname.
-/// @param len Length of `hostname`.
-void os_get_hostname(char *hostname, size_t len)
+/// @param hostname   Buffer to store the hostname.
+/// @param size       Size of `hostname`.
+void os_get_hostname(char *hostname, size_t size)
 {
 #ifdef HAVE_SYS_UTSNAME_H
   struct utsname vutsname;
@@ -124,8 +124,7 @@ void os_get_hostname(char *hostname, size_t len)
   if (uname(&vutsname) < 0) {
     *hostname = '\0';
   } else {
-    strncpy(hostname, vutsname.nodename, len - 1);
-    hostname[len - 1] = '\0';
+    xstrlcpy(hostname, vutsname.nodename, size);
   }
 #else
   // TODO(unknown): Implement this for windows.