vim-patch:8.2.1049: Vim9: leaking memory when using continuation line

Problem:    Vim9: leaking memory when using continuation line.
Solution:   Keep a pointer to the continuation line in evalarg_T.  Centralize
            checking for a next command.

b171fb1790

Omit eval_next_line(): Vim9 script only.

vim-patch:8.2.1050: missing change in struct

Problem:    Missing change in struct.
Solution:   Add missing change.

65a8ed37f7

Co-authored-by: Bram Moolenaar <Bram@vim.org>

src/nvim/digraph.c

@@ -2203,7 +2203,7 @@ bool get_keymap_str(win_T *wp, char *fmt, char *buf, int len)
   curwin = wp;
   STRCPY(buf, "b:keymap_name");       // must be writable
   emsg_skip++;
-  s = p = eval_to_string(buf, NULL, false);
+  s = p = eval_to_string(buf, false);
   emsg_skip--;
   curbuf = old_curbuf;
   curwin = old_curwin;

src/nvim/eval.c

@@ -698,7 +698,7 @@ void eval_patch(const char *const origfile, const char *const difffile, const ch
 /// @param skip  only parse, don't execute
 ///
 /// @return  true or false.
-int eval_to_bool(char *arg, bool *error, char **nextcmd, int skip)
+int eval_to_bool(char *arg, bool *error, exarg_T *eap, int skip)
 {
   typval_T tv;
   bool retval = false;
@@ -706,7 +706,7 @@ int eval_to_bool(char *arg, bool *error, char **nextcmd, int skip)
   if (skip) {
     emsg_skip++;
   }
-  if (eval0(arg, &tv, nextcmd, skip ? NULL : &EVALARG_EVALUATE) == FAIL) {
+  if (eval0(arg, &tv, eap, skip ? NULL : &EVALARG_EVALUATE) == FAIL) {
     *error = true;
   } else {
     *error = false;
@@ -817,13 +817,12 @@ bool eval_expr_to_bool(const typval_T *expr, bool *error)
 /// Top level evaluation function, returning a string
 ///
 /// @param[in]  arg  String to evaluate.
-/// @param  nextcmd  Pointer to the start of the next Ex command.
 /// @param[in]  skip  If true, only do parsing to nextcmd without reporting
 ///                   errors or actually evaluating anything.
 ///
 /// @return [allocated] string result of evaluation or NULL in case of error or
 ///                     when skipping.
-char *eval_to_string_skip(const char *arg, const char **nextcmd, const bool skip)
+char *eval_to_string_skip(char *arg, exarg_T *eap, const bool skip)
   FUNC_ATTR_MALLOC FUNC_ATTR_NONNULL_ARG(1) FUNC_ATTR_WARN_UNUSED_RESULT
 {
   typval_T tv;
@@ -832,8 +831,7 @@ char *eval_to_string_skip(const char *arg, const char **nextcmd, const bool skip
   if (skip) {
     emsg_skip++;
   }
-  if (eval0((char *)arg, &tv, (char **)nextcmd, skip ? NULL : &EVALARG_EVALUATE)
-      == FAIL || skip) {
+  if (eval0(arg, &tv, eap, skip ? NULL : &EVALARG_EVALUATE) == FAIL || skip) {
     retval = NULL;
   } else {
     retval = xstrdup(tv_get_string(&tv));
@@ -863,13 +861,13 @@ int skip_expr(char **pp)
 ///                 a Float to a String.
 ///
 /// @return         pointer to allocated memory, or NULL for failure.
-char *eval_to_string(char *arg, char **nextcmd, bool convert)
+char *eval_to_string(char *arg, bool convert)
 {
   typval_T tv;
   char *retval;
   garray_T ga;
 
-  if (eval0(arg, &tv, nextcmd, &EVALARG_EVALUATE) == FAIL) {
+  if (eval0(arg, &tv, NULL, &EVALARG_EVALUATE) == FAIL) {
     retval = NULL;
   } else {
     if (convert && tv.v_type == VAR_LIST) {
@@ -899,7 +897,7 @@ char *eval_to_string(char *arg, char **nextcmd, bool convert)
 /// textlock.
 ///
 /// @param use_sandbox  when true, use the sandbox.
-char *eval_to_string_safe(char *arg, char **nextcmd, int use_sandbox)
+char *eval_to_string_safe(char *arg, int use_sandbox)
 {
   char *retval;
   funccal_entry_T funccal_entry;
@@ -909,7 +907,7 @@ char *eval_to_string_safe(char *arg, char **nextcmd, int use_sandbox)
     sandbox++;
   }
   textlock++;
-  retval = eval_to_string(arg, nextcmd, false);
+  retval = eval_to_string(arg, false);
   if (use_sandbox) {
     sandbox--;
   }
@@ -1778,7 +1776,7 @@ notify:
 /// @param[out] *errp  set to true for an error, false otherwise;
 ///
 /// @return  a pointer that holds the info.  Null when there is an error.
-void *eval_for_line(const char *arg, bool *errp, char **nextcmdp, int skip)
+void *eval_for_line(const char *arg, bool *errp, exarg_T *eap, int skip)
 {
   forinfo_T *fi = xcalloc(1, sizeof(forinfo_T));
   const char *expr;
@@ -1802,7 +1800,7 @@ void *eval_for_line(const char *arg, bool *errp, char **nextcmdp, int skip)
   if (skip) {
     emsg_skip++;
   }
-  if (eval0(skipwhite(expr + 2), &tv, nextcmdp, &evalarg) == OK) {
+  if (eval0(skipwhite(expr + 2), &tv, eap, &evalarg) == OK) {
     *errp = false;
     if (!skip) {
       if (tv.v_type == VAR_LIST) {
@@ -2230,7 +2228,7 @@ static int eval_func(char **const arg, char *const name, const int name_len, typ
 /// @param evalarg  can be NULL, &EVALARG_EVALUATE or a pointer.
 ///
 /// @return OK or FAIL.
-int eval0(char *arg, typval_T *rettv, char **nextcmd, evalarg_T *const evalarg)
+int eval0(char *arg, typval_T *rettv, exarg_T *eap, evalarg_T *const evalarg)
 {
   int ret;
   char *p;
@@ -2238,6 +2236,9 @@ int eval0(char *arg, typval_T *rettv, char **nextcmd, evalarg_T *const evalarg)
   const int called_emsg_before = called_emsg;
   bool end_error = false;
 
+  if (evalarg != NULL) {
+    evalarg->eval_tofree = NULL;
+  }
   p = skipwhite(arg);
   ret = eval1(&p, rettv, evalarg);
 
@@ -2263,8 +2264,24 @@ int eval0(char *arg, typval_T *rettv, char **nextcmd, evalarg_T *const evalarg)
     }
     ret = FAIL;
   }
-  if (nextcmd != NULL) {
-    *nextcmd = check_nextcmd(p);
+
+  if (eap != NULL) {
+    eap->nextcmd = check_nextcmd(p);
+  }
+
+  if (evalarg != NULL) {
+    if (eap != NULL) {
+      if (evalarg->eval_tofree != NULL) {
+        // We may need to keep the original command line, e.g. for
+        // ":let" it has the variable names.  But we may also need the
+        // new one, "nextcmd" points into it.  Keep both.
+        xfree(eap->cmdline_tofree);
+        eap->cmdline_tofree = *eap->cmdlinep;
+        *eap->cmdlinep = evalarg->eval_tofree;
+      }
+    } else {
+      xfree(evalarg->eval_tofree);
+    }
   }
 
   return ret;
@@ -6537,15 +6554,14 @@ static char *make_expanded_name(const char *in_start, char *expr_start, char *ex
   }
 
   char *retval = NULL;
-  char *nextcmd = NULL;
 
   *expr_start = NUL;
   *expr_end = NUL;
   char c1 = *in_end;
   *in_end = NUL;
 
-  char *temp_result = eval_to_string(expr_start + 1, &nextcmd, false);
-  if (temp_result != NULL && nextcmd == NULL) {
+  char *temp_result = eval_to_string(expr_start + 1, false);
+  if (temp_result != NULL) {
     retval = xmalloc(strlen(temp_result) + (size_t)(expr_start - in_start)
                      + (size_t)(in_end - expr_end) + 1);
     STRCPY(retval, in_start);

src/nvim/eval.h

@@ -273,6 +273,9 @@ typedef struct {
 
   /// copied from exarg_T when "getline" is "getsourceline". Can be NULL.
   void *eval_cookie;   // argument for getline()
+
+  /// pointer to the line obtained with getsourceline()
+  char *eval_tofree;
 } evalarg_T;
 
 /// Flag for expression evaluation.
@@ -281,7 +284,7 @@ enum {
 };
 
 /// Passed to an eval() function to enable evaluation.
-EXTERN evalarg_T EVALARG_EVALUATE INIT(= { EVAL_EVALUATE, NULL });
+EXTERN evalarg_T EVALARG_EVALUATE INIT(= { EVAL_EVALUATE, NULL, NULL });
 
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "eval.h.generated.h"

src/nvim/eval/userfunc.c

@@ -2957,7 +2957,7 @@ void ex_return(exarg_T *eap)
 
   eap->nextcmd = NULL;
   if ((*arg != NUL && *arg != '|' && *arg != '\n')
-      && eval0(arg, &rettv, &eap->nextcmd, &evalarg) != FAIL) {
+      && eval0(arg, &rettv, eap, &evalarg) != FAIL) {
     if (!eap->skip) {
       returning = do_return(eap, false, true, &rettv);
     } else {
@@ -3008,7 +3008,7 @@ void ex_call(exarg_T *eap)
     // instead to skip to any following command, e.g. for:
     //   :if 0 | call dict.foo().bar() | endif.
     emsg_skip++;
-    if (eval0(eap->arg, &rettv, &eap->nextcmd, NULL) != FAIL) {
+    if (eval0(eap->arg, &rettv, eap, NULL) != FAIL) {
       tv_clear(&rettv);
     }
     emsg_skip--;

src/nvim/eval/vars.c

@@ -259,7 +259,7 @@ void ex_let(exarg_T *eap)
       .eval_flags = eap->skip ? 0 : EVAL_EVALUATE,
       .eval_cookie = eap->getline == getsourceline ? eap->cookie : NULL,
     };
-    i = eval0(expr, &rettv, &eap->nextcmd, &evalarg);
+    i = eval0(expr, &rettv, eap, &evalarg);
     if (eap->skip) {
       emsg_skip--;
     }

src/nvim/ex_cmds_defs.h

@@ -185,6 +185,7 @@ struct exarg {
   char *nextcmd;                ///< next command (NULL if none)
   char *cmd;                    ///< the name of the command (except for :make)
   char **cmdlinep;              ///< pointer to pointer of allocated cmdline
+  char *cmdline_tofree;         ///< free later
   cmdidx_T cmdidx;              ///< the index for the command
   uint32_t argt;                ///< flags for the command
   int skip;                     ///< don't execute the command, only parse it

src/nvim/ex_docmd.c

@@ -2328,6 +2328,7 @@ doend:
   }
 
   ex_nesting_level--;
+  xfree(ea.cmdline_tofree);
 
   return ea.nextcmd;
 }
@@ -4432,7 +4433,7 @@ static void ex_colorscheme(exarg_T *eap)
     char *expr = xstrdup("g:colors_name");
 
     emsg_off++;
-    char *p = eval_to_string(expr, NULL, false);
+    char *p = eval_to_string(expr, false);
     emsg_off--;
     xfree(expr);
 

src/nvim/ex_eval.c

@@ -796,7 +796,7 @@ void ex_eval(exarg_T *eap)
     .eval_flags = eap->skip ? 0 : EVAL_EVALUATE,
     .eval_cookie = eap->getline == getsourceline ? eap->cookie : NULL,
   };
-  if (eval0(eap->arg, &tv, &eap->nextcmd, &evalarg) == OK) {
+  if (eval0(eap->arg, &tv, eap, &evalarg) == OK) {
     tv_clear(&tv);
   }
 }
@@ -815,7 +815,7 @@ void ex_if(exarg_T *eap)
     int skip = CHECK_SKIP;
 
     bool error;
-    int result = eval_to_bool(eap->arg, &error, &eap->nextcmd, skip);
+    int result = eval_to_bool(eap->arg, &error, eap, skip);
 
     if (!skip && !error) {
       if (result) {
@@ -910,7 +910,7 @@ void ex_else(exarg_T *eap)
     if (skip && *eap->arg != '"' && ends_excmd(*eap->arg)) {
       semsg(_(e_invexpr2), eap->arg);
     } else {
-      result = eval_to_bool(eap->arg, &error, &eap->nextcmd, skip);
+      result = eval_to_bool(eap->arg, &error, eap, skip);
     }
 
     // When throwing error exceptions, we want to throw always the first
@@ -957,7 +957,7 @@ void ex_while(exarg_T *eap)
     int skip = CHECK_SKIP;
     if (eap->cmdidx == CMD_while) {
       // ":while bool-expr"
-      result = eval_to_bool(eap->arg, &error, &eap->nextcmd, skip);
+      result = eval_to_bool(eap->arg, &error, eap, skip);
     } else {
       void *fi;
 
@@ -969,7 +969,7 @@ void ex_while(exarg_T *eap)
         error = false;
       } else {
         // Evaluate the argument and get the info in a structure.
-        fi = eval_for_line(eap->arg, &error, &eap->nextcmd, skip);
+        fi = eval_for_line(eap->arg, &error, eap, skip);
         cstack->cs_forinfo[cstack->cs_idx] = fi;
       }
 
@@ -1128,12 +1128,11 @@ void ex_endwhile(exarg_T *eap)
 /// Handle ":throw expr"
 void ex_throw(exarg_T *eap)
 {
-  const char *arg = eap->arg;
+  char *arg = eap->arg;
   char *value;
 
   if (*arg != NUL && *arg != '|' && *arg != '\n') {
-    value = eval_to_string_skip(arg, (const char **)&eap->nextcmd,
-                                (bool)eap->skip);
+    value = eval_to_string_skip(arg, eap, eap->skip);
   } else {
     emsg(_(e_argreq));
     value = NULL;

src/nvim/fold.c

@@ -1749,7 +1749,8 @@ char *get_foldtext(win_T *wp, linenr_T lnum, linenr_T lnume, foldinfo_T foldinfo
       curbuf = wp->w_buffer;
 
       emsg_silent++;       // handle exceptions, but don't display errors
-      text = eval_to_string_safe(wp->w_p_fdt, NULL, was_set_insecurely(wp, "foldtext", OPT_LOCAL));
+      text = eval_to_string_safe(wp->w_p_fdt,
+                                 was_set_insecurely(wp, "foldtext", OPT_LOCAL));
       emsg_silent--;
 
       if (text == NULL || did_emsg) {

src/nvim/mapping.c

@@ -1632,7 +1632,7 @@ char *eval_map_expr(mapblock_T *mp, int c)
       api_clear_error(&err);
     }
   } else {
-    p = eval_to_string(expr, NULL, false);
+    p = eval_to_string(expr, false);
     xfree(expr);
   }
   expr_map_lock--;

src/nvim/ops.c

@@ -763,7 +763,7 @@ char *get_expr_line(void)
   }
 
   nested++;
-  rv = eval_to_string(expr_copy, NULL, true);
+  rv = eval_to_string(expr_copy, true);
   nested--;
   xfree(expr_copy);
   return rv;

src/nvim/path.c

@@ -1371,7 +1371,7 @@ static int expand_backtick(garray_T *gap, char *pat, int flags)
   char *cmd = xstrnsave(pat + 1, strlen(pat) - 2);
 
   if (*cmd == '=') {          // `={expr}`: Expand expression
-    buffer = eval_to_string(cmd + 1, &p, true);
+    buffer = eval_to_string(cmd + 1, true);
   } else {
     buffer = get_cmd_output(cmd, NULL, (flags & EW_SILENT) ? kShellOptSilent : 0, NULL);
   }
@@ -1662,7 +1662,7 @@ void simplify_filename(char *filename)
 static char *eval_includeexpr(const char *const ptr, const size_t len)
 {
   set_vim_var_string(VV_FNAME, ptr, (ptrdiff_t)len);
-  char *res = eval_to_string_safe(curbuf->b_p_inex, NULL,
+  char *res = eval_to_string_safe(curbuf->b_p_inex,
                                   was_set_insecurely(curwin, "includeexpr", OPT_LOCAL));
   set_vim_var_string(VV_FNAME, NULL, 0);
   return res;

src/nvim/quickfix.c

@@ -6958,7 +6958,7 @@ void ex_cexpr(exarg_T *eap)
   // Evaluate the expression.  When the result is a string or a list we can
   // use it to fill the errorlist.
   typval_T tv;
-  if (eval0(eap->arg, &tv, &eap->nextcmd, &EVALARG_EVALUATE) == FAIL) {
+  if (eval0(eap->arg, &tv, eap, &EVALARG_EVALUATE) == FAIL) {
     return;
   }
 

src/nvim/regexp.c

@@ -1812,7 +1812,7 @@ static int vim_regsub_both(char *source, typval_T *expr, char *dest, int destlen
         }
         tv_clear(&rettv);
       } else {
-        eval_result[nested] = eval_to_string(source + 2, NULL, true);
+        eval_result[nested] = eval_to_string(source + 2, true);
       }
       nesting--;
 

src/nvim/statusline.c

@@ -985,7 +985,7 @@ int build_stl_str_hl(win_T *wp, char *out, size_t outlen, char *fmt, char *opt_n
     };
     set_var(S_LEN("g:statusline_winid"), &tv, false);
 
-    usefmt = eval_to_string_safe(fmt + 2, NULL, use_sandbox);
+    usefmt = eval_to_string_safe(fmt + 2, use_sandbox);
     if (usefmt == NULL) {
       usefmt = fmt;
     }
@@ -1457,7 +1457,7 @@ int build_stl_str_hl(win_T *wp, char *out, size_t outlen, char *fmt, char *opt_n
       }
 
       // Note: The result stored in `t` is unused.
-      str = eval_to_string_safe(out_p, &t, use_sandbox);
+      str = eval_to_string_safe(out_p, use_sandbox);
 
       curwin = save_curwin;
       curbuf = save_curbuf;