fixup: apply the change on more files

19 files changed, 45 insertions, 45 deletions

diff --git a/src/nvim/api/buffer.c b/src/nvim/api/buffer.c
index 7e64808709..e078d85f33 100644
--- a/src/nvim/api/buffer.c
+++ b/src/nvim/api/buffer.c
@@ -1375,7 +1375,7 @@ static inline void init_line_array(lua_State *lstate, Array *a, size_t size, Are
 /// @param s           String to push
 /// @param len         Size of string
 /// @param idx         0-based index to place s (only used for Lua)
-/// @param replace_nl  Replace newlines ('\n') with null ('\0')
+/// @param replace_nl  Replace newlines ('\n') with null (NUL)
 static void push_linestr(lua_State *lstate, Array *a, const char *s, size_t len, int idx,
                          bool replace_nl, Arena *arena)
 {
@@ -1384,7 +1384,7 @@ static void push_linestr(lua_State *lstate, Array *a, const char *s, size_t len,
     if (s && replace_nl && strchr(s, '\n')) {
       // TODO(bfredl): could manage scratch space in the arena, for the NUL case
       char *tmp = xmemdupz(s, len);
-      strchrsub(tmp, '\n', '\0');
+      strchrsub(tmp, '\n', NUL);
       lua_pushlstring(lstate, tmp, len);
       xfree(tmp);
     } else {
@@ -1397,7 +1397,7 @@ static void push_linestr(lua_State *lstate, Array *a, const char *s, size_t len,
       str = CBUF_TO_ARENA_STR(arena, s, len);
       if (replace_nl) {
         // Vim represents NULs as NLs, but this may confuse clients.
-        strchrsub(str.data, '\n', '\0');
+        strchrsub(str.data, '\n', NUL);
       }
     }
 
diff --git a/src/nvim/api/command.c b/src/nvim/api/command.c
index 779e216c74..5ad439af9c 100644
--- a/src/nvim/api/command.c
+++ b/src/nvim/api/command.c
@@ -193,7 +193,7 @@ Dict(cmd) nvim_parse_cmd(String str, Dict(empty) *opts, Arena *arena, Error *err
   } else {
     nargs[0] = '0';
   }
-  nargs[1] = '\0';
+  nargs[1] = NUL;
   PUT_KEY(result, cmd, nargs, CSTR_TO_ARENA_OBJ(arena, nargs));
 
   char *addr;
@@ -391,7 +391,7 @@ String nvim_cmd(uint64_t channel_id, Dict(cmd) *cmd, Dict(cmd_opts) *opts, Arena
       case kObjectTypeBoolean:
         data_str = arena_alloc(arena, 2, false);
         data_str[0] = elem.data.boolean ? '1' : '0';
-        data_str[1] = '\0';
+        data_str[1] = NUL;
         ADD_C(args, CSTR_AS_OBJ(data_str));
         break;
       case kObjectTypeBuffer:
diff --git a/src/nvim/api/private/validate.c b/src/nvim/api/private/validate.c
index e198c671eb..9fd7d3bfa6 100644
--- a/src/nvim/api/private/validate.c
+++ b/src/nvim/api/private/validate.c
@@ -17,7 +17,7 @@ void api_err_invalid(Error *err, const char *name, const char *val_s, int64_t va
   char *has_space = strchr(name, ' ');
 
   // No value.
-  if (val_s && val_s[0] == '\0') {
+  if (val_s && val_s[0] == NUL) {
     api_set_error(err, errtype, has_space ? "Invalid %s" : "Invalid '%s'", name);
     return;
   }
diff --git a/src/nvim/api/vimscript.c b/src/nvim/api/vimscript.c
index 477cbe2428..124c26d175 100644
--- a/src/nvim/api/vimscript.c
+++ b/src/nvim/api/vimscript.c
@@ -109,7 +109,7 @@ String exec_impl(uint64_t channel_id, String src, Dict(exec_opts) *opts, Error *
     // redir usually (except :echon) prepends a newline.
     if (s.data[0] == '\n') {
       memmove(s.data, s.data + 1, s.size - 1);
-      s.data[s.size - 1] = '\0';
+      s.data[s.size - 1] = NUL;
       s.size = s.size - 1;
     }
     return s;  // Caller will free the memory.
diff --git a/src/nvim/eval/encode.c b/src/nvim/eval/encode.c
index d35ac4eb7b..e216dbdaa6 100644
--- a/src/nvim/eval/encode.c
+++ b/src/nvim/eval/encode.c
@@ -855,7 +855,7 @@ char *encode_tv2string(typval_T *tv, size_t *len)
   if (len != NULL) {
     *len = (size_t)ga.ga_len;
   }
-  ga_append(&ga, '\0');
+  ga_append(&ga, NUL);
   return (char *)ga.ga_data;
 }
 
@@ -883,7 +883,7 @@ char *encode_tv2echo(typval_T *tv, size_t *len)
   if (len != NULL) {
     *len = (size_t)ga.ga_len;
   }
-  ga_append(&ga, '\0');
+  ga_append(&ga, NUL);
   return (char *)ga.ga_data;
 }
 
@@ -908,7 +908,7 @@ char *encode_tv2json(typval_T *tv, size_t *len)
   if (len != NULL) {
     *len = (size_t)ga.ga_len;
   }
-  ga_append(&ga, '\0');
+  ga_append(&ga, NUL);
   return (char *)ga.ga_data;
 }
 
diff --git a/src/nvim/eval/funcs.c b/src/nvim/eval/funcs.c
index e704135366..666d46cdad 100644
--- a/src/nvim/eval/funcs.c
+++ b/src/nvim/eval/funcs.c
@@ -4318,7 +4318,7 @@ static dict_T *create_environment(const dictitem_T *job_env, const bool clear_en
 
   // Set $NVIM (in the child process) to v:servername. #3118
   char *nvim_addr = get_vim_var_str(VV_SEND_SERVER);
-  if (nvim_addr[0] != '\0') {
+  if (nvim_addr[0] != NUL) {
     dictitem_T *dv = tv_dict_find(env, S_LEN("NVIM"));
     if (dv) {
       tv_dict_item_remove(env, dv);
@@ -9174,13 +9174,13 @@ static void f_termopen(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
   size_t len = home_replace(NULL, NameBuff, IObuff, sizeof(IObuff), true);
   // Trim slash.
   if (len != 1 && (IObuff[len - 1] == '\\' || IObuff[len - 1] == '/')) {
-    IObuff[len - 1] = '\0';
+    IObuff[len - 1] = NUL;
   }
 
   if (len == 1 && IObuff[0] == '/') {
     // Avoid ambiguity in the URI when CWD is root directory.
     IObuff[1] = '.';
-    IObuff[2] = '\0';
+    IObuff[2] = NUL;
   }
 
   // Terminal URI: "term://$CWD//$PID:$CMD"
diff --git a/src/nvim/eval/typval.c b/src/nvim/eval/typval.c
index 1ea1fe46d2..13b31ab30f 100644
--- a/src/nvim/eval/typval.c
+++ b/src/nvim/eval/typval.c
@@ -1824,7 +1824,7 @@ char *callback_to_string(Callback *cb, Arena *arena)
     snprintf(msg, msglen, "<vim partial: %s>", cb->data.partial->pt_name);
     break;
   default:
-    *msg = '\0';
+    *msg = NUL;
     break;
   }
   return msg;
diff --git a/src/nvim/eval/window.c b/src/nvim/eval/window.c
index d7485c12a3..86495f1cb6 100644
--- a/src/nvim/eval/window.c
+++ b/src/nvim/eval/window.c
@@ -272,7 +272,7 @@ static int get_winnr(tabpage_T *tp, typval_T *argvar)
         // if count is not specified, default to 1
         count = 1;
       }
-      if (endp != NULL && *endp != '\0') {
+      if (endp != NULL && *endp != NUL) {
         if (strequal(endp, "j")) {
           twin = win_vert_neighbor(tp, twin, false, count);
         } else if (strequal(endp, "k")) {
diff --git a/src/nvim/event/socket.c b/src/nvim/event/socket.c
index 017f159fa1..1214c3e336 100644
--- a/src/nvim/event/socket.c
+++ b/src/nvim/event/socket.c
@@ -35,7 +35,7 @@ int socket_watcher_init(Loop *loop, SocketWatcher *watcher, const char *endpoint
   if (host_end && addr != host_end) {
     // Split user specified address into two strings, addr(hostname) and port.
     // The port part in watcher->addr will be updated later.
-    *host_end = '\0';
+    *host_end = NUL;
     char *port = host_end + 1;
     intmax_t iport;
 
diff --git a/src/nvim/lua/secure.c b/src/nvim/lua/secure.c
index a84d6c4d65..61277949c4 100644
--- a/src/nvim/lua/secure.c
+++ b/src/nvim/lua/secure.c
@@ -104,12 +104,12 @@ void ex_trust(exarg_T *eap)
     action = "deny";
   } else if (strcmp(arg1, "++remove") == 0) {
     action = "remove";
-  } else if (*arg1 != '\0') {
+  } else if (*arg1 != NUL) {
     semsg(e_invarg2, arg1);
     goto theend;
   }
 
-  if (path[0] == '\0') {
+  if (path[0] == NUL) {
     path = NULL;
   }
 
diff --git a/src/nvim/lua/treesitter.c b/src/nvim/lua/treesitter.c
index e87cf756a8..b13a162074 100644
--- a/src/nvim/lua/treesitter.c
+++ b/src/nvim/lua/treesitter.c
@@ -279,7 +279,7 @@ static const char *input_cb(void *payload, uint32_t byte_index, TSPoint position
 
   memcpy(buf, line + position.column, tocopy);
   // Translate embedded \n to NUL
-  memchrsub(buf, '\n', '\0', tocopy);
+  memchrsub(buf, '\n', NUL, tocopy);
   *bytes_read = (uint32_t)tocopy;
   if (tocopy < BUFSIZE) {
     // now add the final \n. If it didn't fit, input_cb will be called again
diff --git a/src/nvim/msgpack_rpc/server.c b/src/nvim/msgpack_rpc/server.c
index 56b03d67d0..341f638a55 100644
--- a/src/nvim/msgpack_rpc/server.c
+++ b/src/nvim/msgpack_rpc/server.c
@@ -131,7 +131,7 @@ bool server_owns_pipe_address(const char *path)
 /// @returns 0: success, 1: validation error, 2: already listening, -errno: failed to bind/listen.
 int server_start(const char *addr)
 {
-  if (addr == NULL || addr[0] == '\0') {
+  if (addr == NULL || addr[0] == NUL) {
     WLOG("Empty or NULL address");
     return 1;
   }
diff --git a/src/nvim/os/env.c b/src/nvim/os/env.c
index 5a79004c41..4689414559 100644
--- a/src/nvim/os/env.c
+++ b/src/nvim/os/env.c
@@ -63,13 +63,13 @@ const char *os_getenv(const char *name)
   FUNC_ATTR_NONNULL_ALL
 {
   char *e = NULL;
-  if (name[0] == '\0') {
+  if (name[0] == NUL) {
     return NULL;
   }
   int r = 0;
   if (map_has(cstr_t, &envmap, name)
       && !!(e = (char *)pmap_get(cstr_t)(&envmap, name))) {
-    if (e[0] != '\0') {
+    if (e[0] != NUL) {
       // Found non-empty cached env var.
       // NOTE: This risks incoherence if an in-process library changes the
       //       environment without going through our os_setenv() wrapper.  If
@@ -85,11 +85,11 @@ const char *os_getenv(const char *name)
   if (r == UV_ENOBUFS) {
     e = xmalloc(size);
     r = uv_os_getenv(name, e, &size);
-    if (r != 0 || size == 0 || e[0] == '\0') {
+    if (r != 0 || size == 0 || e[0] == NUL) {
       XFREE_CLEAR(e);
       goto end;
     }
-  } else if (r != 0 || size == 0 || buf[0] == '\0') {
+  } else if (r != 0 || size == 0 || buf[0] == NUL) {
     e = NULL;
     goto end;
   } else {
@@ -110,7 +110,7 @@ end:
 bool os_env_exists(const char *name)
   FUNC_ATTR_NONNULL_ALL
 {
-  if (name[0] == '\0') {
+  if (name[0] == NUL) {
     return false;
   }
   // Use a tiny buffer because we don't care about the value: if uv_os_getenv()
@@ -134,14 +134,14 @@ bool os_env_exists(const char *name)
 int os_setenv(const char *name, const char *value, int overwrite)
   FUNC_ATTR_NONNULL_ALL
 {
-  if (name[0] == '\0') {
+  if (name[0] == NUL) {
     return -1;
   }
 #ifdef MSWIN
   if (!overwrite && os_getenv(name) != NULL) {
     return 0;
   }
-  if (value[0] == '\0') {
+  if (value[0] == NUL) {
     // Windows (Vim-compat): Empty string undefines the env var.
     return os_unsetenv(name);
   }
@@ -174,7 +174,7 @@ int os_setenv(const char *name, const char *value, int overwrite)
 int os_unsetenv(const char *name)
   FUNC_ATTR_NONNULL_ALL
 {
-  if (name[0] == '\0') {
+  if (name[0] == NUL) {
     return -1;
   }
   pmap_del2(&envmap, name);
@@ -366,7 +366,7 @@ void os_get_hostname(char *hostname, size_t size)
   struct utsname vutsname;
 
   if (uname(&vutsname) < 0) {
-    *hostname = '\0';
+    *hostname = NUL;
   } else {
     xstrlcpy(hostname, vutsname.nodename, size);
   }
@@ -374,12 +374,12 @@ void os_get_hostname(char *hostname, size_t size)
   wchar_t host_utf16[MAX_COMPUTERNAME_LENGTH + 1];
   DWORD host_wsize = sizeof(host_utf16) / sizeof(host_utf16[0]);
   if (GetComputerNameW(host_utf16, &host_wsize) == 0) {
-    *hostname = '\0';
+    *hostname = NUL;
     DWORD err = GetLastError();
     semsg("GetComputerNameW failed: %d", err);
     return;
   }
-  host_utf16[host_wsize] = '\0';
+  host_utf16[host_wsize] = NUL;
 
   char *host_utf8;
   int conversion_result = utf16_to_utf8(host_utf16, -1, &host_utf8);
@@ -391,7 +391,7 @@ void os_get_hostname(char *hostname, size_t size)
   xfree(host_utf8);
 #else
   emsg("os_get_hostname failed: missing uname()");
-  *hostname = '\0';
+  *hostname = NUL;
 #endif
 }
 
@@ -885,9 +885,9 @@ void vim_get_prefix_from_exepath(char *exe_name)
   // but c_grammar.lua does not recognize it (yet).
   xstrlcpy(exe_name, get_vim_var_str(VV_PROGPATH), MAXPATHL * sizeof(*exe_name));
   char *path_end = path_tail_with_sep(exe_name);
-  *path_end = '\0';  // remove the trailing "nvim.exe"
+  *path_end = NUL;  // remove the trailing "nvim.exe"
   path_end = path_tail(exe_name);
-  *path_end = '\0';  // remove the trailing "bin/"
+  *path_end = NUL;  // remove the trailing "bin/"
 }
 
 /// Vim getenv() wrapper with special handling of $HOME, $VIM, $VIMRUNTIME,
diff --git a/src/nvim/os/fs.c b/src/nvim/os/fs.c
index 13e87a1ca5..b681b2f832 100644
--- a/src/nvim/os/fs.c
+++ b/src/nvim/os/fs.c
@@ -302,7 +302,7 @@ static bool is_executable_ext(const char *name, char **abspath)
   char *nameext = strrchr(name, '.');
   size_t nameext_len = nameext ? strlen(nameext) : 0;
   xstrlcpy(os_buf, name, sizeof(os_buf));
-  char *buf_end = xstrchrnul(os_buf, '\0');
+  char *buf_end = xstrchrnul(os_buf, NUL);
   const char *pathext = os_getenv("PATHEXT");
   if (!pathext) {
     pathext = ".com;.exe;.bat;.cmd";
@@ -310,7 +310,7 @@ static bool is_executable_ext(const char *name, char **abspath)
   const char *ext = pathext;
   while (*ext) {
     // If $PATHEXT itself contains dot:
-    if (ext[0] == '.' && (ext[1] == '\0' || ext[1] == ENV_SEPCHAR)) {
+    if (ext[0] == '.' && (ext[1] == NUL || ext[1] == ENV_SEPCHAR)) {
       if (is_executable(name, abspath)) {
         return true;
       }
@@ -436,7 +436,7 @@ FILE *os_fopen(const char *path, const char *flags)
   assert(flags != NULL && strlen(flags) > 0 && strlen(flags) <= 2);
   int iflags = 0;
   // Per table in fopen(3) manpage.
-  if (flags[1] == '\0' || flags[1] == 'b') {
+  if (flags[1] == NUL || flags[1] == 'b') {
     switch (flags[0]) {
     case 'r':
       iflags = O_RDONLY;
diff --git a/src/nvim/os/pty_process_win.c b/src/nvim/os/pty_process_win.c
index f73baed490..39c3966c1c 100644
--- a/src/nvim/os/pty_process_win.c
+++ b/src/nvim/os/pty_process_win.c
@@ -399,7 +399,7 @@ static int build_env_block(dict_T *denv, wchar_t **env_block)
     QUEUE_INSERT_TAIL(&env_q, &env_node->node);
   }
 
-  // Additional '\0' after the final entry
+  // Additional NUL after the final entry
   env_block_len++;
 
   *env_block = xmalloc(sizeof(**env_block) * env_block_len);
diff --git a/src/nvim/os/shell.c b/src/nvim/os/shell.c
index d572e9b933..026f14ebc8 100644
--- a/src/nvim/os/shell.c
+++ b/src/nvim/os/shell.c
@@ -648,13 +648,13 @@ char *shell_argv_to_str(char **const argv)
     p++;
   }
   if (n < maxsize) {
-    rv[n - 1] = '\0';
+    rv[n - 1] = NUL;
   } else {
     // Command too long, show ellipsis: "/bin/bash 'foo' 'bar'..."
     rv[maxsize - 4] = '.';
     rv[maxsize - 3] = '.';
     rv[maxsize - 2] = '.';
-    rv[maxsize - 1] = '\0';
+    rv[maxsize - 1] = NUL;
   }
   return rv;
 }
@@ -861,7 +861,7 @@ static int do_os_system(char **argv, const char *input, size_t len, char **outpu
 {
   out_data_decide_throttle(0);  // Initialize throttle decider.
   out_data_ring(NULL, 0);       // Initialize output ring-buffer.
-  bool has_input = (input != NULL && input[0] != '\0');
+  bool has_input = (input != NULL && input[0] != NUL);
 
   // the output buffer
   DynamicBuffer buf = DYNAMIC_BUFFER_INIT;
@@ -1024,7 +1024,7 @@ static bool out_data_decide_throttle(size_t size)
   static uint64_t started = 0;  // Start time of the current throttle.
   static size_t received = 0;  // Bytes observed since last throttle.
   static size_t visit = 0;  // "Pulse" count of the current throttle.
-  static char pulse_msg[] = { ' ', ' ', ' ', '\0' };
+  static char pulse_msg[] = { ' ', ' ', ' ', NUL };
 
   if (!size) {
     bool previous_decision = (visit > 0);
diff --git a/src/nvim/os/stdpaths.c b/src/nvim/os/stdpaths.c
index e5bdd56fe6..e4435bcaa8 100644
--- a/src/nvim/os/stdpaths.c
+++ b/src/nvim/os/stdpaths.c
@@ -69,7 +69,7 @@ static const char *const xdg_defaults[] = {
 const char *get_appname(void)
 {
   const char *env_val = os_getenv("NVIM_APPNAME");
-  if (env_val == NULL || *env_val == '\0') {
+  if (env_val == NULL || *env_val == NUL) {
     env_val = "nvim";
   }
   return env_val;
diff --git a/src/nvim/tui/terminfo.c b/src/nvim/tui/terminfo.c
index 3cf9650428..657bd6dd10 100644
--- a/src/nvim/tui/terminfo.c
+++ b/src/nvim/tui/terminfo.c
@@ -35,7 +35,7 @@ bool terminfo_is_term_family(const char *term, const char *family)
          // The screen terminfo may have a terminal name like screen.xterm. By making
          // the dot(.) a valid separator, such terminal names will also be the
          // terminal family of the screen.
-         && ('\0' == term[flen] || '-' == term[flen] || '.' == term[flen]);
+         && (NUL == term[flen] || '-' == term[flen] || '.' == term[flen]);
 }
 
 bool terminfo_is_bsd_console(const char *term)
diff --git a/src/nvim/tui/tui.c b/src/nvim/tui/tui.c
index dc8c8def5b..650133e6a2 100644
--- a/src/nvim/tui/tui.c
+++ b/src/nvim/tui/tui.c
@@ -2508,7 +2508,7 @@ static const char *tui_get_stty_erase(int fd)
   struct termios t;
   if (tcgetattr(fd, &t) != -1) {
     stty_erase[0] = (char)t.c_cc[VERASE];
-    stty_erase[1] = '\0';
+    stty_erase[1] = NUL;
     DLOG("stty/termios:erase=%s", stty_erase);
   }
 #endif