fix -F vs. -t

From 75160ba9c925c305a41b9002533e0c8013fe15ed Mon Sep 17 00:00:00 2001
From: Eric Blake <[email protected]>
Date: Wed, 17 Oct 2007 19:44:13 -0600
Subject: [PATCH] Fix 'm4 -F file -t undefined'.

* src/freeze.c (produce_frozen_state): Avoid core dump.
* doc/m4.texinfo (Using frozen files): Test for the bug.

Signed-off-by: Eric Blake <[email protected]>
---
 ChangeLog      |    7 ++
 NEWS           |    2 +
 doc/m4.texinfo |   10 +++
 src/freeze.c   |  192 ++++++++++++++++++++++++++++---------------------------
 4 files changed, 117 insertions(+), 94 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 9e334f1..2e4a12b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2007-10-17  Eric Blake  <[email protected]>
+
+	Fix 'm4 -F file -t undefined'.
+	* src/freeze.c (produce_frozen_state): Avoid core dump.
+	* doc/m4.texinfo (Using frozen files): Test for the bug.
+	* NEWS: Mention the fix.
+
 2007-10-09  Eric Blake  <[email protected]>
 
 	* NEWS: Document recent speedups.
diff --git a/NEWS b/NEWS
index af9b7ae..66e16c3 100644
--- a/NEWS
+++ b/NEWS
@@ -4,6 +4,8 @@ Foundation, Inc.
 
 Version 1.4.11 - ?? ??? 2007, by ????  (CVS version 1.4.10a)
 
+* Fix core dump in 'm4 -F file -t undefined', present since -F was
+  introduced in 1.3.
 * Fix regression introduced in 1.4.9b in the `divert' builtin when more
   than 512 kibibytes are saved in diversions on platforms like NetBSD
   where fopen(name,"a+") seeks to the end of the file.
diff --git a/doc/m4.texinfo b/doc/m4.texinfo
index 64e37ba..3bece3a 100644
--- a/doc/m4.texinfo
+++ b/doc/m4.texinfo
@@ -6029,6 +6029,16 @@ are handled correctly, as well as undefined or renamed builtins, and
 changed strings for quotes or comments.  And future releases of
 @acronym{GNU} M4 will improve on the utility of frozen files.
 
+@ignore
+@c This example is not worth putting in the manual, but caused core
+@c dumps in all versions prior to 1.4.11.
+
+@comment options: -F /dev/null
+@example
+traceon(`undefined')dnl
+@end example
+@end ignore
+
 When an @code{m4} run is to be frozen, the automatic undiversion
 which takes place at end of execution is inhibited.  Instead, all
 positively numbered diversions are saved into the frozen file.
diff --git a/src/freeze.c b/src/freeze.c
index fb4e93d..89a4c35 100644
--- a/src/freeze.c
+++ b/src/freeze.c
@@ -127,6 +127,10 @@ INTERNAL ERROR: builtin not found in builtin table!"));
 	      fputc ('\n', file);
 	      break;
 
+	    case TOKEN_VOID:
+	      /* Ignore placeholder tokens that exist due to traceon.  */
+	      break;
+
 	    default:
 	      M4ERROR ((warning_status, 0, "\
 INTERNAL ERROR: bad token data type in freeze_one_symbol ()"));
@@ -210,15 +214,15 @@ reload_frozen_state (const char *name)
      character to the next directive or to EOF.  */
 
 #define GET_DIRECTIVE \
-  do                                                            \
-    {                                                           \
-      GET_CHARACTER;                                            \
-      if (character == '#')                                     \
-        {                                                       \
-          while (character != EOF && character != '\n')         \
-            GET_CHARACTER;                                      \
-          VALIDATE ('\n');                                      \
-        }                                                       \
+  do								\
+    {								\
+      GET_CHARACTER;						\
+      if (character == '#')					\
+	{							\
+	  while (character != EOF && character != '\n')		\
+	    GET_CHARACTER;					\
+	  VALIDATE ('\n');					\
+	}							\
     }                                                           \
   while (character == '\n')
 
@@ -238,131 +242,131 @@ reload_frozen_state (const char *name)
   GET_NUMBER (number[0]);
   if (number[0] > 1)
     M4ERROR ((EXIT_MISMATCH, 0,
-              "frozen file version %d greater than max supported of 1",
+	      "frozen file version %d greater than max supported of 1",
 	      number[0]));
   else if (number[0] < 1)
     M4ERROR ((EXIT_FAILURE, 0,
-              "ill-formed frozen file, version directive expected"));
+	      "ill-formed frozen file, version directive expected"));
   VALIDATE ('\n');
 
   GET_DIRECTIVE;
   while (character != EOF)
     {
       switch (character)
-        {
-        default:
-          M4ERROR ((EXIT_FAILURE, 0, "ill-formed frozen file"));
-
-        case 'C':
-        case 'D':
-        case 'F':
-        case 'T':
-        case 'Q':
-          operation = character;
-          GET_CHARACTER;
+	{
+	default:
+	  M4ERROR ((EXIT_FAILURE, 0, "ill-formed frozen file"));
 
-          /* Get string lengths.  Accept a negative diversion number.  */
+	case 'C':
+	case 'D':
+	case 'F':
+	case 'T':
+	case 'Q':
+	  operation = character;
+	  GET_CHARACTER;
 
-          if (operation == 'D' && character == '-')
-            {
-              GET_CHARACTER;
-              GET_NUMBER (number[0]);
-              number[0] = -number[0];
-            }
-          else
-            GET_NUMBER (number[0]);
-          VALIDATE (',');
-          GET_CHARACTER;
-          GET_NUMBER (number[1]);
-          VALIDATE ('\n');
+	  /* Get string lengths.  Accept a negative diversion number.  */
 
-          if (operation != 'D')
-            {
+	  if (operation == 'D' && character == '-')
+	    {
+	      GET_CHARACTER;
+	      GET_NUMBER (number[0]);
+	      number[0] = -number[0];
+	    }
+	  else
+	    GET_NUMBER (number[0]);
+	  VALIDATE (',');
+	  GET_CHARACTER;
+	  GET_NUMBER (number[1]);
+	  VALIDATE ('\n');
+
+	  if (operation != 'D')
+	    {
 
-              /* Get first string contents.  */
+	      /* Get first string contents.  */
 
-              if (number[0] + 1 > allocated[0])
-                {
-                  free (string[0]);
-                  allocated[0] = number[0] + 1;
-                  string[0] = xcharalloc ((size_t) allocated[0]);
-                }
+	      if (number[0] + 1 > allocated[0])
+		{
+		  free (string[0]);
+		  allocated[0] = number[0] + 1;
+		  string[0] = xcharalloc ((size_t) allocated[0]);
+		}
 
-              if (number[0] > 0)
-                if (!fread (string[0], (size_t) number[0], 1, file))
-                  M4ERROR ((EXIT_FAILURE, 0, "premature end of frozen file"));
+	      if (number[0] > 0)
+		if (!fread (string[0], (size_t) number[0], 1, file))
+		  M4ERROR ((EXIT_FAILURE, 0, "premature end of frozen file"));
 
-              string[0][number[0]] = '\0';
-            }
+	      string[0][number[0]] = '\0';
+	    }
 
-          /* Get second string contents.  */
+	  /* Get second string contents.  */
 
-          if (number[1] + 1 > allocated[1])
-            {
-              free (string[1]);
-              allocated[1] = number[1] + 1;
-              string[1] = xcharalloc ((size_t) allocated[1]);
-            }
+	  if (number[1] + 1 > allocated[1])
+	    {
+	      free (string[1]);
+	      allocated[1] = number[1] + 1;
+	      string[1] = xcharalloc ((size_t) allocated[1]);
+	    }
 
-          if (number[1] > 0)
-            if (!fread (string[1], (size_t) number[1], 1, file))
-              M4ERROR ((EXIT_FAILURE, 0, "premature end of frozen file"));
+	  if (number[1] > 0)
+	    if (!fread (string[1], (size_t) number[1], 1, file))
+	      M4ERROR ((EXIT_FAILURE, 0, "premature end of frozen file"));
 
-          string[1][number[1]] = '\0';
-          GET_CHARACTER;
-          VALIDATE ('\n');
+	  string[1][number[1]] = '\0';
+	  GET_CHARACTER;
+	  VALIDATE ('\n');
 
-          /* Act according to operation letter.  */
+	  /* Act according to operation letter.  */
 
-          switch (operation)
-            {
-            case 'C':
+	  switch (operation)
+	    {
+	    case 'C':
 
-              /* Change comment strings.  */
+	      /* Change comment strings.  */
 
-              set_comment (string[0], string[1]);
-              break;
+	      set_comment (string[0], string[1]);
+	      break;
 
-            case 'D':
+	    case 'D':
 
-              /* Select a diversion and add a string to it.  */
+	      /* Select a diversion and add a string to it.  */
 
-              make_diversion (number[0]);
-              if (number[1] > 0)
-                output_text (string[1], number[1]);
-              break;
+	      make_diversion (number[0]);
+	      if (number[1] > 0)
+		output_text (string[1], number[1]);
+	      break;
 
-            case 'F':
+	    case 'F':
 
-              /* Enter a macro having a builtin function as a definition.  */
+	      /* Enter a macro having a builtin function as a definition.  */
 
-              bp = find_builtin_by_name (string[1]);
-              define_builtin (string[0], bp, SYMBOL_PUSHDEF);
-              break;
+	      bp = find_builtin_by_name (string[1]);
+	      define_builtin (string[0], bp, SYMBOL_PUSHDEF);
+	      break;
 
-            case 'T':
+	    case 'T':
 
-              /* Enter a macro having an expansion text as a definition.  */
+	      /* Enter a macro having an expansion text as a definition.  */
 
-              define_user_macro (string[0], string[1], SYMBOL_PUSHDEF);
-              break;
+	      define_user_macro (string[0], string[1], SYMBOL_PUSHDEF);
+	      break;
 
-            case 'Q':
+	    case 'Q':
 
-              /* Change quote strings.  */
+	      /* Change quote strings.  */
 
-              set_quotes (string[0], string[1]);
-              break;
+	      set_quotes (string[0], string[1]);
+	      break;
 
-            default:
+	    default:
 
-              /* Cannot happen.  */
+	      /* Cannot happen.  */
 
-              break;
-            }
-          break;
+	      break;
+	    }
+	  break;
 
-        }
+	}
       GET_DIRECTIVE;
     }
 
-- 
1.5.3.2