[7264] info fix crash

[gavinsmith0123]

Revision: 7264
          http://svn.sv.gnu.org/viewvc/?view=rev&root=texinfo&revision=7264
Author:   gavin
Date:     2016-07-17 16:44:53 +0000 (Sun, 17 Jul 2016)
Log Message:
-----------
info fix crash

Modified Paths:
--------------
    trunk/ChangeLog
    trunk/info/indices.c
    trunk/info/nodes.c
    trunk/info/nodes.h

Modified: trunk/ChangeLog
===================================================================
--- trunk/ChangeLog     2016-07-16 19:52:28 UTC (rev 7263)
+++ trunk/ChangeLog     2016-07-17 16:44:53 UTC (rev 7264)
@@ -1,3 +1,11 @@
+2016-07-17  Gavin Smith  <address@hidden>
+
+       * info/indices.c (apropos_in_all_indices): Only free file buffer 
+       if we had to load it.  Otherwise the file buffer could still be 
+       referenced.  Fixes crash reported by "address@hidden".
+       * info/nodes.c (check_loaded_file): Function split out from 
+       info_find_file.
+
 2016-07-16  Gavin Smith  <address@hidden>
 
        * dco/texinfo-tex-test.texi (Test of auxiliary files): Add test

Modified: trunk/info/indices.c
===================================================================
--- trunk/info/indices.c        2016-07-16 19:52:28 UTC (rev 7263)
+++ trunk/info/indices.c        2016-07-17 16:44:53 UTC (rev 7264)
@@ -558,7 +558,7 @@
   for (dir_index = 0; dir_menu[dir_index]; dir_index++)
     {
       REFERENCE **this_index, *this_item;
-      FILE_BUFFER *this_fb;
+      FILE_BUFFER *this_fb, *loaded_file = 0;
 
       this_item = dir_menu[dir_index];
       if (!this_item->filename)
@@ -574,11 +574,14 @@
       if (i < dir_index)
         continue;
 
-      this_fb = info_find_file (this_item->filename);
+      this_fb = check_loaded_file (this_item->filename);
 
       if (!this_fb)
-        continue;
+        this_fb = loaded_file = info_find_file (this_item->filename);
 
+      if (!this_fb)
+        continue; /* Couldn't load file. */
+
       if (this_fb && inform)
         message_in_echo_area (_("Scanning indices of '%s'..."), 
this_item->filename);
 
@@ -602,9 +605,16 @@
           free (old_indices);
           }
         }
-      /* Try to avoid running out of memory */
-      free (this_fb->contents);
-      this_fb->contents = NULL;
+
+      /* Try to avoid running out of memory by not loading all of the
+         Info files on the system into memory.  This is risky because we
+         may have a pointer into the file buffer, so only free the contents
+         if we have just loaded the file. */
+      if (loaded_file)
+        {
+          free (loaded_file->contents);
+          loaded_file->contents = NULL;
+        }
     }
 
   /* Build a list of the references which contain SEARCH_STRING. */

Modified: trunk/info/nodes.c
===================================================================
--- trunk/info/nodes.c  2016-07-16 19:52:28 UTC (rev 7263)
+++ trunk/info/nodes.c  2016-07-17 16:44:53 UTC (rev 7264)
@@ -544,24 +544,17 @@
 static void forget_info_file (FILE_BUFFER *file_buffer);
 static void info_reload_file_buffer_contents (FILE_BUFFER *fb);
 
-/* Locate the file named by FILENAME, and return the information structure
-   describing this file.  The file may appear in our list of loaded files
-   already, or it may not.  If it does not already appear, find the file,
-   and add it to the list of loaded files.  If the file cannot be found,
-   return a NULL FILE_BUFFER *. */
+/* Try to find a file in our list of already loaded files. */
 FILE_BUFFER *
-info_find_file (char *filename)
+check_loaded_file (char *filename)
 {
-  int i;
+  int is_fullpath, i;
   FILE_BUFFER *file_buffer;
-  char *fullpath;
-  int is_fullpath;
   
   /* If full path to the file has been given, we must find it exactly. */
   is_fullpath = IS_ABSOLUTE (filename)
                 || filename[0] == '.' && IS_SLASH(filename[1]);
 
-  /* First try to find the file in our list of already loaded files. */
   if (info_loaded_files)
     {
       for (i = 0; (file_buffer = info_loaded_files[i]); i++)
@@ -601,11 +594,31 @@
             return file_buffer;
           }
     }
+  return 0;
+}
 
+/* Locate the file named by FILENAME, and return the information structure
+   describing this file.  The file may appear in our list of loaded files
+   already, or it may not.  If it does not already appear, find the file,
+   and add it to the list of loaded files.  If the file cannot be found,
+   return a NULL FILE_BUFFER *. */
+FILE_BUFFER *
+info_find_file (char *filename)
+{
+  FILE_BUFFER *file_buffer;
+  char *fullpath;
+  int is_fullpath;
+  
+  file_buffer = check_loaded_file (filename);
+  if (file_buffer)
+    return file_buffer;
+
   /* The file wasn't loaded.  Try to load it now. */
 
   /* Get the full pathname of this file, as known by the info system.
      That is to say, search along INFOPATH and expand tildes, etc. */
+  is_fullpath = IS_ABSOLUTE (filename)
+                || filename[0] == '.' && IS_SLASH(filename[1]);
   if (!is_fullpath)
     fullpath = info_find_fullpath (filename, 0);
   else

Modified: trunk/info/nodes.h
===================================================================
--- trunk/info/nodes.h  2016-07-16 19:52:28 UTC (rev 7263)
+++ trunk/info/nodes.h  2016-07-17 16:44:53 UTC (rev 7264)
@@ -141,6 +141,8 @@
    return a NULL FILE_BUFFER *. */
 FILE_BUFFER *info_find_file (char *filename);
 
+FILE_BUFFER *check_loaded_file (char *filename);
+
 FILE_BUFFER *info_find_subfile (char *filename);
 
 TAG *info_create_tag (void);