Merge #6947 from ZyX-I/consistent-get_keymap

6 files changed, 189 insertions, 139 deletions

diff --git a/src/nvim/eval.c b/src/nvim/eval.c
index 18aa5bf763..662270e788 100644
--- a/src/nvim/eval.c
+++ b/src/nvim/eval.c
@@ -12117,9 +12117,11 @@ static void get_maparg(typval_T *argvars, typval_T *rettv, int exact)
   xfree(keys_buf);
 
   if (!get_dict) {
-    /* Return a string. */
-    if (rhs != NULL)
-      rettv->vval.v_string = str2special_save(rhs, FALSE);
+    // Return a string.
+    if (rhs != NULL) {
+      rettv->vval.v_string = (char_u *)str2special_save(
+          (const char *)rhs, false, false);
+    }
 
   } else {
     tv_dict_alloc_ret(rettv);
@@ -12154,7 +12156,8 @@ void mapblock_fill_dict(dict_T *const dict,
                         bool compatible)
   FUNC_ATTR_NONNULL_ALL
 {
-  char_u *lhs = str2special_save(mp->m_keys, true);
+  char *const lhs = str2special_save((const char *)mp->m_keys,
+                                     compatible, !compatible);
   char *const mapmode = map_mode_to_chars(mp->m_mode);
   varnumber_T noremap_value;
 
@@ -12168,18 +12171,21 @@ void mapblock_fill_dict(dict_T *const dict,
     noremap_value = mp->m_noremap == REMAP_SCRIPT ? 2 : !!mp->m_noremap;
   }
 
-  tv_dict_add_str(dict, S_LEN("lhs"), (const char *)lhs);
-  tv_dict_add_str(dict, S_LEN("rhs"), (const char *)mp->m_orig_str);
+  if (compatible) {
+    tv_dict_add_str(dict, S_LEN("rhs"), (const char *)mp->m_orig_str);
+  } else {
+    tv_dict_add_allocated_str(dict, S_LEN("rhs"),
+                              str2special_save((const char *)mp->m_str, false,
+                                               true));
+  }
+  tv_dict_add_allocated_str(dict, S_LEN("lhs"), lhs);
   tv_dict_add_nr(dict, S_LEN("noremap"), noremap_value);
   tv_dict_add_nr(dict, S_LEN("expr"),  mp->m_expr ? 1 : 0);
   tv_dict_add_nr(dict, S_LEN("silent"), mp->m_silent ? 1 : 0);
   tv_dict_add_nr(dict, S_LEN("sid"), (varnumber_T)mp->m_script_ID);
   tv_dict_add_nr(dict, S_LEN("buffer"), (varnumber_T)buffer_value);
   tv_dict_add_nr(dict, S_LEN("nowait"), mp->m_nowait ? 1 : 0);
-  tv_dict_add_str(dict, S_LEN("mode"), mapmode);
-
-  xfree(lhs);
-  xfree(mapmode);
+  tv_dict_add_allocated_str(dict, S_LEN("mode"), mapmode);
 }
 
 /*
diff --git a/src/nvim/eval/typval.c b/src/nvim/eval/typval.c
index 4521085519..c339a5cdd2 100644
--- a/src/nvim/eval/typval.c
+++ b/src/nvim/eval/typval.c
@@ -1387,11 +1387,32 @@ int tv_dict_add_str(dict_T *const d,
                     const char *const val)
   FUNC_ATTR_NONNULL_ALL
 {
+  return tv_dict_add_allocated_str(d, key, key_len, xstrdup(val));
+}
+
+/// Add a string entry to dictionary
+///
+/// Unlike tv_dict_add_str() saves val to the new dictionary item in place of
+/// creating a new copy.
+///
+/// @warning String will be freed even in case addition fails.
+///
+/// @param[out]  d  Dictionary to add entry to.
+/// @param[in]  key  Key to add.
+/// @param[in]  key_len  Key length.
+/// @param[in]  val  String to add.
+///
+/// @return OK in case of success, FAIL when key already exists.
+int tv_dict_add_allocated_str(dict_T *const d,
+                              const char *const key, const size_t key_len,
+                              char *const val)
+  FUNC_ATTR_NONNULL_ALL
+{
   dictitem_T *const item = tv_dict_item_alloc_len(key, key_len);
 
   item->di_tv.v_lock = VAR_UNLOCKED;
   item->di_tv.v_type = VAR_STRING;
-  item->di_tv.vval.v_string = (char_u *)xstrdup(val);
+  item->di_tv.vval.v_string = (char_u *)val;
   if (tv_dict_add(d, item) == FAIL) {
     tv_dict_item_free(item);
     return FAIL;
diff --git a/src/nvim/getchar.c b/src/nvim/getchar.c
index 4e42042959..fc1b8ccfcb 100644
--- a/src/nvim/getchar.c
+++ b/src/nvim/getchar.c
@@ -1806,7 +1806,7 @@ static int vgetorpeek(int advance)
                  * <M-a> and then changing 'encoding'. Beware
                  * that 0x80 is escaped. */
                 char_u *p1 = mp->m_keys;
-                char_u *p2 = mb_unescape(&p1);
+                char_u *p2 = (char_u *)mb_unescape((const char **)&p1);
 
                 if (has_mbyte && p2 != NULL && MB_BYTE2LEN(c1) > MB_PTR2LEN(p2))
                   mlen = 0;
@@ -3999,12 +3999,10 @@ int put_escstr(FILE *fd, char_u *strstart, int what)
     return OK;
   }
 
-  for (; *str != NUL; ++str) {
-    char_u  *p;
-
-    /* Check for a multi-byte character, which may contain escaped
-     * K_SPECIAL and CSI bytes */
-    p = mb_unescape(&str);
+  for (; *str != NUL; str++) {
+    // Check for a multi-byte character, which may contain escaped
+    // K_SPECIAL and CSI bytes.
+    const char *p = mb_unescape((const char **)&str);
     if (p != NULL) {
       while (*p != NUL)
         if (fputc(*p++, fd) < 0)
diff --git a/src/nvim/mbyte.c b/src/nvim/mbyte.c
index d5907da2ed..5b00a4b9a8 100644
--- a/src/nvim/mbyte.c
+++ b/src/nvim/mbyte.c
@@ -1739,52 +1739,55 @@ int mb_charlen_len(char_u *str, int len)
   return count;
 }
 
-/*
- * Try to un-escape a multi-byte character.
- * Used for the "to" and "from" part of a mapping.
- * Return the un-escaped string if it is a multi-byte character, and advance
- * "pp" to just after the bytes that formed it.
- * Return NULL if no multi-byte char was found.
- */
-char_u * mb_unescape(char_u **pp)
-{
-  static char_u buf[6];
-  int n;
-  int m = 0;
-  char_u              *str = *pp;
-
-  /* Must translate K_SPECIAL KS_SPECIAL KE_FILLER to K_SPECIAL and CSI
-   * KS_EXTRA KE_CSI to CSI.
-   * Maximum length of a utf-8 character is 4 bytes. */
-  for (n = 0; str[n] != NUL && m < 4; ++n) {
-    if (str[n] == K_SPECIAL
-        && str[n + 1] == KS_SPECIAL
-        && str[n + 2] == KE_FILLER) {
-      buf[m++] = K_SPECIAL;
-      n += 2;
-    } else if ((str[n] == K_SPECIAL
-          )
-        && str[n + 1] == KS_EXTRA
-        && str[n + 2] == (int)KE_CSI) {
-      buf[m++] = CSI;
-      n += 2;
-    } else if (str[n] == K_SPECIAL
-        )
-      break;                    /* a special key can't be a multibyte char */
-    else
-      buf[m++] = str[n];
-    buf[m] = NUL;
+/// Try to unescape a multibyte character
+///
+/// Used for the rhs and lhs of the mappings.
+///
+/// @param[in,out]  pp  String to unescape. Is advanced to just after the bytes
+///                     that form a multibyte character.
+///
+/// @return Unescaped string if it is a multibyte character, NULL if no
+///         multibyte character was found. Returns a static buffer, always one
+///         and the same.
+const char *mb_unescape(const char **const pp)
+  FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_ALL
+{
+  static char buf[6];
+  size_t buf_idx = 0;
+  uint8_t *str = (uint8_t *)(*pp);
+
+  // Must translate K_SPECIAL KS_SPECIAL KE_FILLER to K_SPECIAL and CSI
+  // KS_EXTRA KE_CSI to CSI.
+  // Maximum length of a utf-8 character is 4 bytes.
+  for (size_t str_idx = 0; str[str_idx] != NUL && buf_idx < 4; str_idx++) {
+    if (str[str_idx] == K_SPECIAL
+        && str[str_idx + 1] == KS_SPECIAL
+        && str[str_idx + 2] == KE_FILLER) {
+      buf[buf_idx++] = (char)K_SPECIAL;
+      str_idx += 2;
+    } else if ((str[str_idx] == K_SPECIAL)
+               && str[str_idx + 1] == KS_EXTRA
+               && str[str_idx + 2] == KE_CSI) {
+      buf[buf_idx++] = (char)CSI;
+      str_idx += 2;
+    } else if (str[str_idx] == K_SPECIAL) {
+      break;  // A special key can't be a multibyte char.
+    } else {
+      buf[buf_idx++] = (char)str[str_idx];
+    }
+    buf[buf_idx] = NUL;
 
-    /* Return a multi-byte character if it's found.  An illegal sequence
-     * will result in a 1 here. */
-    if ((*mb_ptr2len)(buf) > 1) {
-      *pp = str + n + 1;
+    // Return a multi-byte character if it's found.  An illegal sequence
+    // will result in a 1 here.
+    if (utf_ptr2len((const char_u *)buf) > 1) {
+      *pp = (const char *)str + buf_idx + 1;
       return buf;
     }
 
-    /* Bail out quickly for ASCII. */
-    if (buf[0] < 128)
+    // Bail out quickly for ASCII.
+    if ((uint8_t)buf[0] < 128) {
       break;
+    }
   }
   return NULL;
 }
diff --git a/src/nvim/message.c b/src/nvim/message.c
index 057ce75f79..8a9d8e1bc6 100644
--- a/src/nvim/message.c
+++ b/src/nvim/message.c
@@ -1269,7 +1269,7 @@ msg_outtrans_special (
       string = "<Space>";
       str++;
     } else {
-      string = (const char *)str2special((char_u **)&str, from);
+      string = str2special((const char **)&str, from, false);
     }
     const int len = vim_strsize((char_u *)string);
     // Highlight special keys
@@ -1281,108 +1281,125 @@ msg_outtrans_special (
   return retval;
 }
 
-/*
- * Return the lhs or rhs of a mapping, with the key codes turned into printable
- * strings, in an allocated string.
- */
-char_u *
-str2special_save (
-    char_u *str,
-    int is_lhs          /* TRUE for lhs, FALSE for rhs */
-)
+/// Convert string, replacing key codes with printables
+///
+/// Used for lhs or rhs of mappings.
+///
+/// @param[in]  str  String to convert.
+/// @param[in]  replace_spaces  Convert spaces into `<Space>`, normally used fo
+///                             lhs, but not rhs.
+/// @param[in]  replace_lt  Convert `<` into `<lt>`.
+///
+/// @return [allocated] Converted string.
+char *str2special_save(const char *const str, const bool replace_spaces,
+                       const bool replace_lt)
+  FUNC_ATTR_NONNULL_ALL FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_MALLOC
+  FUNC_ATTR_NONNULL_RET
 {
   garray_T ga;
-  char_u      *p = str;
-
   ga_init(&ga, 1, 40);
-  while (*p != NUL)
-    ga_concat(&ga, str2special(&p, is_lhs));
+
+  const char *p = str;
+  while (*p != NUL) {
+    ga_concat(&ga, (const char_u *)str2special(&p, replace_spaces, replace_lt));
+  }
   ga_append(&ga, NUL);
-  return (char_u *)ga.ga_data;
+  return (char *)ga.ga_data;
 }
 
-/*
- * Return the printable string for the key codes at "*sp".
- * Used for translating the lhs or rhs of a mapping to printable chars.
- * Advances "sp" to the next code.
- */
-char_u *
-str2special (
-    char_u **sp,
-    int from               /* TRUE for lhs of mapping */
-)
-{
-  int c;
-  static char_u buf[7];
-  char_u              *str = *sp;
-  int modifiers = 0;
-  int special = FALSE;
-
-  if (has_mbyte) {
-    char_u  *p;
-
-    /* Try to un-escape a multi-byte character.  Return the un-escaped
-     * string if it is a multi-byte character. */
-    p = mb_unescape(sp);
-    if (p != NULL)
-      return p;
+/// Convert character, replacing key one key code with printable representation
+///
+/// @param[in,out]  sp  String to convert. Is advanced to the next key code.
+/// @param[in]  replace_spaces  Convert spaces into <Space>, normally used for
+///                             lhs, but not rhs.
+/// @param[in]  replace_lt  Convert `<` into `<lt>`.
+///
+/// @return Converted key code, in a static buffer. Buffer is always one and the
+///         same, so save converted string somewhere before running str2special
+///         for the second time.
+const char *str2special(const char **const sp, const bool replace_spaces,
+                        const bool replace_lt)
+  FUNC_ATTR_NONNULL_ALL FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_RET
+{
+  static char buf[7];
+
+  // Try to un-escape a multi-byte character.  Return the un-escaped
+  // string if it is a multi-byte character.
+  const char *const p = mb_unescape(sp);
+  if (p != NULL) {
+    return p;
   }
 
-  c = *str;
+  const char *str = *sp;
+  int c = (uint8_t)(*str);
+  int modifiers = 0;
+  bool special = false;
   if (c == K_SPECIAL && str[1] != NUL && str[2] != NUL) {
-    if (str[1] == KS_MODIFIER) {
-      modifiers = str[2];
+    if ((uint8_t)str[1] == KS_MODIFIER) {
+      modifiers = (uint8_t)str[2];
       str += 3;
-      c = *str;
+      c = (uint8_t)(*str);
     }
     if (c == K_SPECIAL && str[1] != NUL && str[2] != NUL) {
-      c = TO_SPECIAL(str[1], str[2]);
+      c = TO_SPECIAL((uint8_t)str[1], (uint8_t)str[2]);
       str += 2;
-      if (c == KS_ZERO)         /* display <Nul> as ^@ or <Nul> */
+      if (c == KS_ZERO) {  // display <Nul> as ^@ or <Nul>
         c = NUL;
+      }
+    }
+    if (IS_SPECIAL(c) || modifiers) {  // Special key.
+      special = true;
     }
-    if (IS_SPECIAL(c) || modifiers)     /* special key */
-      special = TRUE;
   }
 
-  if (has_mbyte && !IS_SPECIAL(c)) {
-    int len = (*mb_ptr2len)(str);
+  if (!IS_SPECIAL(c)) {
+    const int len = utf_ptr2len((const char_u *)str);
 
-    /* For multi-byte characters check for an illegal byte. */
-    if (has_mbyte && MB_BYTE2LEN(*str) > len) {
-      transchar_nonprint(buf, c);
+    // Check for an illegal byte.
+    if (MB_BYTE2LEN((uint8_t)(*str)) > len) {
+      transchar_nonprint((char_u *)buf, c);
       *sp = str + 1;
       return buf;
     }
-    /* Since 'special' is TRUE the multi-byte character 'c' will be
-     * processed by get_special_key_name() */
-    c = (*mb_ptr2char)(str);
+    // Since 'special' is TRUE the multi-byte character 'c' will be
+    // processed by get_special_key_name().
+    c = utf_ptr2char((const char_u *)str);
     *sp = str + len;
-  } else
+  } else {
     *sp = str + 1;
+  }
 
-  /* Make unprintable characters in <> form, also <M-Space> and <Tab>.
-   * Use <Space> only for lhs of a mapping. */
-  if (special || char2cells(c) > 1 || (from && c == ' '))
-    return get_special_key_name(c, modifiers);
+  // Make unprintable characters in <> form, also <M-Space> and <Tab>.
+  if (special
+      || char2cells(c) > 1
+      || (replace_spaces && c == ' ')
+      || (replace_lt && c == '<')) {
+    return (const char *)get_special_key_name(c, modifiers);
+  }
   buf[0] = c;
   buf[1] = NUL;
   return buf;
 }
 
-/*
- * Translate a key sequence into special key names.
- */
-void str2specialbuf(char_u *sp, char_u *buf, int len)
+/// Convert string, replacing key codes with printables
+///
+/// @param[in]  str  String to convert.
+/// @param[out]  buf  Buffer to save results to.
+/// @param[in]  len  Buffer length.
+void str2specialbuf(const char *sp, char *buf, size_t len)
+  FUNC_ATTR_NONNULL_ALL
 {
-  char_u      *s;
-
-  *buf = NUL;
   while (*sp) {
-    s = str2special(&sp, FALSE);
-    if ((int)(STRLEN(s) + STRLEN(buf)) < len)
-      STRCAT(buf, s);
+    const char *s = str2special(&sp, false, false);
+    const size_t s_len = strlen(s);
+    if (s_len <= len) {
+      break;
+    }
+    memcpy(buf, s, s_len);
+    buf += s_len;
+    len -= s_len;
   }
+  *buf = NUL;
 }
 
 /*
diff --git a/src/nvim/option.c b/src/nvim/option.c
index b48ffae85b..7287db6eb8 100644
--- a/src/nvim/option.c
+++ b/src/nvim/option.c
@@ -5175,9 +5175,13 @@ static int put_setstring(FILE *fd, char *cmd, char *name, char_u **valuep, int e
      * CTRL-V or backslash */
     if (valuep == &p_pt) {
       s = *valuep;
-      while (*s != NUL)
-        if (put_escstr(fd, str2special(&s, FALSE), 2) == FAIL)
+      while (*s != NUL) {
+        if (put_escstr(fd, (char_u *)str2special((const char **)&s, false,
+                                                 false), 2)
+            == FAIL) {
           return FAIL;
+        }
+      }
     } else if (expand) {
       buf = xmalloc(MAXPATHL);
       home_replace(NULL, *valuep, buf, MAXPATHL, FALSE);
@@ -6173,15 +6177,16 @@ option_value2string (
     }
   } else {  // P_STRING
     varp = *(char_u **)(varp);
-    if (varp == NULL)                       /* just in case */
+    if (varp == NULL) {  // Just in case.
       NameBuff[0] = NUL;
-    else if (opp->flags & P_EXPAND)
-      home_replace(NULL, varp, NameBuff, MAXPATHL, FALSE);
-    /* Translate 'pastetoggle' into special key names */
-    else if ((char_u **)opp->var == &p_pt)
-      str2specialbuf(p_pt, NameBuff, MAXPATHL);
-    else
+    } else if (opp->flags & P_EXPAND) {
+      home_replace(NULL, varp, NameBuff, MAXPATHL, false);
+    // Translate 'pastetoggle' into special key names.
+    } else if ((char_u **)opp->var == &p_pt) {
+      str2specialbuf((const char *)p_pt, (char *)NameBuff, MAXPATHL);
+    } else {
       STRLCPY(NameBuff, varp, MAXPATHL);
+    }
   }
 }