vim-patch:8.1.0743: giving error messages is not flexible

Problem:    Giving error messages is not flexible.
Solution:   Add semsg().  Change argument from "char_u *" to "char *", also
            for msg() and get rid of most MSG macros. (Ozaki Kiichi, closes
            vim/vim#3302)  Also make emsg() accept a "char *" argument.  Get rid of
            an enormous number of type casts.
https://github.com/vim/vim/commit/f9e3e09fdc93be9f0d47afbc6c7df1188c2a5a0d

75 files changed, 1700 insertions, 1744 deletions

diff --git a/src/nvim/api/vim.c b/src/nvim/api/vim.c
index f51b5536e7..2f1df31858 100644
--- a/src/nvim/api/vim.c
+++ b/src/nvim/api/vim.c
@@ -1724,7 +1724,7 @@ static void write_msg(String message, bool to_err)
 #define PUSH_CHAR(i, pos, line_buf, msg) \
   if (message.data[i] == NL || pos == LINE_BUFFER_SIZE - 1) { \
     line_buf[pos] = NUL; \
-    msg((char_u *)line_buf); \
+    msg(line_buf); \
     pos = 0; \
     continue; \
   } \
diff --git a/src/nvim/autocmd.c b/src/nvim/autocmd.c
index d991b88131..b1d22ffc74 100644
--- a/src/nvim/autocmd.c
+++ b/src/nvim/autocmd.c
@@ -313,9 +313,9 @@ static void au_del_group(char_u *name)
 {
   int i = au_find_group(name);
   if (i == AUGROUP_ERROR) {  // the group doesn't exist
-    EMSG2(_("E367: No such group: \"%s\""), name);
+    semsg(_("E367: No such group: \"%s\""), name);
   } else if (i == current_augroup) {
-    EMSG(_("E936: Cannot delete the current group"));
+    emsg(_("E936: Cannot delete the current group"));
   } else {
     event_T event;
     AutoPat *ap;
@@ -372,7 +372,7 @@ void do_augroup(char_u *arg, int del_group)
 {
   if (del_group) {
     if (*arg == NUL) {
-      EMSG(_(e_argreq));
+      emsg(_(e_argreq));
     } else {
       au_del_group(arg);
     }
@@ -469,7 +469,7 @@ static char_u *find_end_event(char_u *arg, int have_group)
 
   if (*arg == '*') {
     if (arg[1] && !ascii_iswhite(arg[1])) {
-      EMSG2(_("E215: Illegal character after *: %s"), arg);
+      semsg(_("E215: Illegal character after *: %s"), arg);
       return NULL;
     }
     pat = arg + 1;
@@ -477,9 +477,9 @@ static char_u *find_end_event(char_u *arg, int have_group)
     for (pat = arg; *pat && *pat != '|' && !ascii_iswhite(*pat); pat = p) {
       if ((int)event_name2nr(pat, &p) >= NUM_EVENTS) {
         if (have_group) {
-          EMSG2(_("E216: No such event: %s"), pat);
+          semsg(_("E216: No such event: %s"), pat);
         } else {
-          EMSG2(_("E216: No such group or event: %s"), pat);
+          semsg(_("E216: No such group or event: %s"), pat);
         }
         return NULL;
       }
@@ -651,7 +651,7 @@ void do_autocmd(char_u *arg_in, int forceit)
         // Check for "++once" flag.
         if (STRNCMP(cmd, "++once", 6) == 0 && ascii_iswhite(cmd[6])) {
           if (once) {
-            EMSG2(_(e_duparg2), "++once");
+            semsg(_(e_duparg2), "++once");
           }
           once = true;
           cmd = skipwhite(cmd + 6);
@@ -660,7 +660,7 @@ void do_autocmd(char_u *arg_in, int forceit)
         // Check for "++nested" flag.
         if ((STRNCMP(cmd, "++nested", 8) == 0 && ascii_iswhite(cmd[8]))) {
           if (nested) {
-            EMSG2(_(e_duparg2), "++nested");
+            semsg(_(e_duparg2), "++nested");
           }
           nested = true;
           cmd = skipwhite(cmd + 8);
@@ -669,7 +669,7 @@ void do_autocmd(char_u *arg_in, int forceit)
         // Check for the old (deprecated) "nested" flag.
         if (STRNCMP(cmd, "nested", 6) == 0 && ascii_iswhite(cmd[6])) {
           if (nested) {
-            EMSG2(_(e_duparg2), "nested");
+            semsg(_(e_duparg2), "nested");
           }
           nested = true;
           cmd = skipwhite(cmd + 6);
@@ -699,7 +699,7 @@ void do_autocmd(char_u *arg_in, int forceit)
   last_group = AUGROUP_ERROR;  // for listing the group name
   if (*arg == '*' || *arg == NUL || *arg == '|') {
     if (!forceit && *cmd != NUL) {
-      EMSG(_(e_cannot_define_autocommands_for_all_events));
+      emsg(_(e_cannot_define_autocommands_for_all_events));
     } else {
       for (event_T event = (event_T)0; event < NUM_EVENTS;
            event = (event_T)(event + 1)) {
@@ -899,7 +899,7 @@ static int do_autocmd_event(event_T event, char_u *pat, bool once, int nested, c
         // refuse to add buffer-local ap if buffer number is invalid
         if (is_buflocal
             && (buflocal_nr == 0 || buflist_findnr(buflocal_nr) == NULL)) {
-          emsgf(_("E680: <buffer=%d>: invalid buffer number "), buflocal_nr);
+          semsg(_("E680: <buffer=%d>: invalid buffer number "), buflocal_nr);
           return FAIL;
         }
 
@@ -974,7 +974,7 @@ int do_doautocmd(char_u *arg, bool do_msg, bool *did_something)
   group = au_get_grouparg(&arg);
 
   if (*arg == '*') {
-    EMSG(_("E217: Can't execute autocommands for ALL events"));
+    emsg(_("E217: Can't execute autocommands for ALL events"));
     return FAIL;
   }
 
@@ -1414,7 +1414,7 @@ static bool apply_autocmds_group(event_T event, char_u *fname, char_u *fname_io,
   // Allow nesting of autocommands, but restrict the depth, because it's
   // possible to create an endless loop.
   if (nesting == 10) {
-    EMSG(_("E218: autocommand nesting too deep"));
+    emsg(_("E218: autocommand nesting too deep"));
     goto BYPASS_AU;
   }
 
diff --git a/src/nvim/buffer.c b/src/nvim/buffer.c
index 62d41051e0..db436c0afc 100644
--- a/src/nvim/buffer.c
+++ b/src/nvim/buffer.c
@@ -186,7 +186,7 @@ int open_buffer(int read_stdin, exarg_T *eap, int flags)
     // If there is no memfile at all, exit.
     // This is OK, since there are no changes to lose.
     if (curbuf == NULL) {
-      EMSG(_("E82: Cannot allocate any buffer, exiting..."));
+      emsg(_("E82: Cannot allocate any buffer, exiting..."));
 
       // Don't try to do any saving, with "curbuf" NULL almost nothing
       // will work.
@@ -194,7 +194,7 @@ int open_buffer(int read_stdin, exarg_T *eap, int flags)
       getout(2);
     }
 
-    EMSG(_("E83: Cannot allocate buffer, using other one..."));
+    emsg(_("E83: Cannot allocate buffer, using other one..."));
     enter_buffer(curbuf);
     if (old_tw != curbuf->b_p_tw) {
       check_colorcolumn(curwin);
@@ -439,7 +439,7 @@ bool close_buffer(win_T *win, buf_T *buf, int action, bool abort_if_last)
   // Disallow deleting the buffer when it is locked (already being closed or
   // halfway a command that relies on it). Unloading is allowed.
   if (buf->b_locked > 0 && (del_buf || wipe_buf)) {
-    EMSG(_("E937: Attempt to delete a buffer that is in use"));
+    emsg(_("E937: Attempt to delete a buffer that is in use"));
     return false;
   }
 
@@ -466,13 +466,13 @@ bool close_buffer(win_T *win, buf_T *buf, int action, bool abort_if_last)
     if (apply_autocmds(EVENT_BUFWINLEAVE, buf->b_fname, buf->b_fname, false,
                        buf) && !bufref_valid(&bufref)) {
       // Autocommands deleted the buffer.
-      EMSG(_(e_auabort));
+      emsg(_(e_auabort));
       return false;
     }
     buf->b_locked--;
     if (abort_if_last && last_nonfloat(win)) {
       // Autocommands made this the only window.
-      EMSG(_(e_auabort));
+      emsg(_(e_auabort));
       return false;
     }
 
@@ -483,13 +483,13 @@ bool close_buffer(win_T *win, buf_T *buf, int action, bool abort_if_last)
       if (apply_autocmds(EVENT_BUFHIDDEN, buf->b_fname, buf->b_fname, false,
                          buf) && !bufref_valid(&bufref)) {
         // Autocommands deleted the buffer.
-        EMSG(_(e_auabort));
+        emsg(_(e_auabort));
         return false;
       }
       buf->b_locked--;
       if (abort_if_last && last_nonfloat(win)) {
         // Autocommands made this the only window.
-        EMSG(_(e_auabort));
+        emsg(_(e_auabort));
         return false;
       }
     }
@@ -944,11 +944,11 @@ void handle_swap_exists(bufref_T *old_curbuf)
 /// @param end_bnr  buffer nr or last buffer nr in a range
 ///
 /// @return  error message or NULL
-char_u *do_bufdel(int command, char_u *arg, int addr_count, int start_bnr, int end_bnr, int forceit)
+char *do_bufdel(int command, char_u *arg, int addr_count, int start_bnr, int end_bnr, int forceit)
 {
   int do_current = 0;             // delete current buffer?
   int deleted = 0;                // number of buffers deleted
-  char_u *errormsg = NULL;   // return value
+  char *errormsg = NULL;   // return value
   int bnr;                        // buffer number
   char_u *p;
 
@@ -957,7 +957,7 @@ char_u *do_bufdel(int command, char_u *arg, int addr_count, int start_bnr, int e
   } else {
     if (addr_count == 2) {
       if (*arg) {               // both range and argument is not allowed
-        return (char_u *)_(e_trailing);
+        return _(e_trailing);
       }
       bnr = start_bnr;
     } else {    // addr_count == 1
@@ -1013,7 +1013,7 @@ char_u *do_bufdel(int command, char_u *arg, int addr_count, int start_bnr, int e
       } else {
         STRCPY(IObuff, _("E517: No buffers were wiped out"));
       }
-      errormsg = IObuff;
+      errormsg = (char *)IObuff;
     } else if (deleted >= p_report) {
       if (command == DOBUF_UNLOAD) {
         smsg(NGETTEXT("%d buffer unloaded", "%d buffers unloaded", (unsigned long)deleted),
@@ -1043,7 +1043,7 @@ static int empty_curbuf(int close_others, int forceit, int action)
   buf_T *buf = curbuf;
 
   if (action == DOBUF_UNLOAD) {
-    EMSG(_("E90: Cannot unload last buffer"));
+    emsg(_("E90: Cannot unload last buffer"));
     return FAIL;
   }
 
@@ -1116,7 +1116,7 @@ int do_buffer(int action, int start, int dir, int count, int forceit)
       } while (buf != curbuf && !bufIsChanged(buf));
     }
     if (!bufIsChanged(buf)) {
-      EMSG(_("E84: No modified buffer found"));
+      emsg(_("E84: No modified buffer found"));
       return FAIL;
     }
   } else if (start == DOBUF_FIRST && count) {  // find specified buffer number
@@ -1149,7 +1149,7 @@ int do_buffer(int action, int start, int dir, int count, int forceit)
       }
       if (bp == buf) {
         // back where we started, didn't find anything.
-        EMSG(_("E85: There is no listed buffer"));
+        emsg(_("E85: There is no listed buffer"));
         return FAIL;
       }
     }
@@ -1159,12 +1159,12 @@ int do_buffer(int action, int start, int dir, int count, int forceit)
     if (start == DOBUF_FIRST) {
       // don't warn when deleting
       if (!unload) {
-        EMSGN(_(e_nobufnr), count);
+        semsg(_(e_nobufnr), (int64_t)count);
       }
     } else if (dir == FORWARD) {
-      EMSG(_("E87: Cannot go beyond last buffer"));
+      emsg(_("E87: Cannot go beyond last buffer"));
     } else {
-      EMSG(_("E88: Cannot go before first buffer"));
+      emsg(_("E88: Cannot go before first buffer"));
     }
     return FAIL;
   }
@@ -1195,9 +1195,9 @@ int do_buffer(int action, int start, int dir, int count, int forceit)
           return FAIL;
         }
       } else {
-        EMSGN(_("E89: No write since last change for buffer %" PRId64
+        semsg(_("E89: No write since last change for buffer %" PRId64
                 " (add ! to override)"),
-              buf->b_fnum);
+              (int64_t)buf->b_fnum);
         return FAIL;
       }
     }
@@ -1208,7 +1208,7 @@ int do_buffer(int action, int start, int dir, int count, int forceit)
           return FAIL;
         }
       } else {
-        EMSG2(_("E89: %s will be killed (add ! to override)"),
+        semsg(_("E89: %s will be killed (add ! to override)"),
               (char *)buf->b_fname);
         return FAIL;
       }
@@ -1597,9 +1597,9 @@ void no_write_message(void)
 {
   if (curbuf->terminal
       && channel_job_running((uint64_t)curbuf->b_p_channel)) {
-    EMSG(_("E948: Job still running (add ! to end the job)"));
+    emsg(_("E948: Job still running (add ! to end the job)"));
   } else {
-    EMSG(_("E37: No write since last change (add ! to override)"));
+    emsg(_("E37: No write since last change (add ! to override)"));
   }
 }
 
@@ -1608,9 +1608,9 @@ void no_write_message_nobang(const buf_T *const buf)
 {
   if (buf->terminal
       && channel_job_running((uint64_t)buf->b_p_channel)) {
-    EMSG(_("E948: Job still running"));
+    emsg(_("E948: Job still running"));
   } else {
-    EMSG(_("E37: No write since last change"));
+    emsg(_("E37: No write since last change"));
   }
 }
 
@@ -1793,7 +1793,7 @@ buf_T *buflist_new(char_u *ffname_arg, char_u *sfname_arg, linenr_T lnum, int fl
     buf->b_fnum = top_file_num++;
     pmap_put(handle_T)(&buffer_handles, buf->b_fnum, buf);
     if (top_file_num < 0) {  // wrap around (may cause duplicates)
-      EMSG(_("W14: Warning: List of file names overflow"));
+      emsg(_("W14: Warning: List of file names overflow"));
       if (emsg_silent == 0) {
         ui_flush();
         os_delay(3001L, true);  // make sure it is noticed
@@ -1962,9 +1962,9 @@ int buflist_getfile(int n, linenr_T lnum, int options, int forceit)
   buf = buflist_findnr(n);
   if (buf == NULL) {
     if ((options & GETF_ALT) && n == 0) {
-      EMSG(_(e_noalt));
+      emsg(_(e_noalt));
     } else {
-      EMSGN(_("E92: Buffer %" PRId64 " not found"), n);
+      semsg(_("E92: Buffer %" PRId64 " not found"), (int64_t)n);
     }
     return FAIL;
   }
@@ -2224,9 +2224,9 @@ int buflist_findpat(const char_u *pattern, const char_u *pattern_end, bool unlis
   }
 
   if (match == -2) {
-    EMSG2(_("E93: More than one match for %s"), pattern);
+    semsg(_("E93: More than one match for %s"), pattern);
   } else if (match < 0) {
-    EMSG2(_("E94: No matching buffer for %s"), pattern);
+    semsg(_("E94: No matching buffer for %s"), pattern);
   }
   return match;
 }
@@ -2795,7 +2795,7 @@ int setfname(buf_T *buf, char_u *ffname_arg, char_u *sfname_arg, bool message)
     if (obuf != NULL && obuf != buf) {
       if (obuf->b_ml.ml_mfp != NULL) {          // it's loaded, fail
         if (message) {
-          EMSG(_("E95: Buffer with this name already exists"));
+          emsg(_("E95: Buffer with this name already exists"));
         }
         xfree(ffname);
         return FAIL;
@@ -2900,7 +2900,7 @@ char_u *getaltfname(bool errmsg)
 
   if (buflist_name_nr(0, &fname, &dummy) == FAIL) {
     if (errmsg) {
-      EMSG(_(e_noalt));
+      emsg(_(e_noalt));
     }
     return NULL;
   }
@@ -5386,7 +5386,7 @@ bool bt_dontwrite_msg(const buf_T *const buf)
   FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT
 {
   if (bt_dontwrite(buf)) {
-    EMSG(_("E382: Cannot write, 'buftype' option is set"));
+    emsg(_("E382: Cannot write, 'buftype' option is set"));
     return true;
   }
   return false;
diff --git a/src/nvim/change.c b/src/nvim/change.c
index 2450c56838..21a4798bfe 100644
--- a/src/nvim/change.c
+++ b/src/nvim/change.c
@@ -759,7 +759,7 @@ int del_bytes(colnr_T count, bool fixpos_arg, bool use_delcombine)
   }
   // If "count" is negative the caller must be doing something wrong.
   if (count < 1) {
-    IEMSGN("E292: Invalid count for del_bytes(): %ld", count);
+    siemsg("E292: Invalid count for del_bytes(): %ld", (int64_t)count);
     return FAIL;
   }
 
diff --git a/src/nvim/channel.c b/src/nvim/channel.c
index cfeaafe77a..0eae87c1f8 100644
--- a/src/nvim/channel.c
+++ b/src/nvim/channel.c
@@ -319,7 +319,7 @@ Channel *channel_job_start(char **argv, CallbackReader on_stdout, CallbackReader
 
   if (pty) {
     if (detach) {
-      EMSG2(_(e_invarg2), "terminal/pty job cannot be detached");
+      semsg(_(e_invarg2), "terminal/pty job cannot be detached");
       shell_free_argv(argv);
       if (env) {
         tv_dict_free(env);
@@ -369,7 +369,7 @@ Channel *channel_job_start(char **argv, CallbackReader on_stdout, CallbackReader
 
   int status = process_spawn(proc, has_in, has_out, has_err);
   if (status) {
-    EMSG3(_(e_jobspawn), os_strerror(status), cmd);
+    semsg(_(e_jobspawn), os_strerror(status), cmd);
     xfree(cmd);
     if (proc->env) {
       tv_dict_free(proc->env);
@@ -672,7 +672,7 @@ void channel_reader_callbacks(Channel *chan, CallbackReader *reader)
           tv_dict_add_list(reader->self, reader->type, strlen(reader->type),
                            data);
         } else {
-          EMSG3(_(e_streamkey), reader->type, chan->id);
+          semsg(_(e_streamkey), reader->type, chan->id);
         }
       } else {
         channel_callback_call(chan, reader);
diff --git a/src/nvim/context.c b/src/nvim/context.c
index 4a8e645d2c..614a3ce30e 100644
--- a/src/nvim/context.c
+++ b/src/nvim/context.c
@@ -316,7 +316,7 @@ static inline msgpack_sbuffer array_to_sbuf(Array array)
   object_to_vim(ARRAY_OBJ(array), &list_tv, &err);
 
   if (!encode_vim_list_to_buf(list_tv.vval.v_list, &sbuf.size, &sbuf.data)) {
-    EMSG(_("E474: Failed to convert list to msgpack string buffer"));
+    emsg(_("E474: Failed to convert list to msgpack string buffer"));
   }
   sbuf.alloc = sbuf.size;
 
diff --git a/src/nvim/cursor_shape.c b/src/nvim/cursor_shape.c
index 18cade1052..644bb2c324 100644
--- a/src/nvim/cursor_shape.c
+++ b/src/nvim/cursor_shape.c
@@ -93,7 +93,7 @@ Array mode_style_array(void)
 /// @param what SHAPE_CURSOR or SHAPE_MOUSE ('mouseshape')
 ///
 /// @returns error message for an illegal option, NULL otherwise.
-char_u *parse_shape_opt(int what)
+char *parse_shape_opt(int what)
 {
   char_u *modep;
   char_u *colonp;
@@ -126,10 +126,10 @@ char_u *parse_shape_opt(int what)
       commap = vim_strchr(modep, ',');
 
       if (colonp == NULL || (commap != NUL