Don't free uninitialized hash_table

* src/dir.c (clear_directory_contents): We use ht_vec to mark when
we have initialized the hash_table: don't free if it's NULL.
(everywhere): Use NULL instead of 0 when working with pointers.

1 files changed, 40 insertions, 42 deletions

diff --git a/src/dir.c b/src/dir.c
index 855dc3d5..641a46df 100644
--- a/src/dir.c
+++ b/src/dir.c
@@ -76,12 +76,12 @@ dosify (const char *filename)
   char *df;
   int i;
 
-  if (filename == 0 || _USE_LFN)
+  if (filename == NULL || _USE_LFN)
     return filename;
 
   /* FIXME: what about filenames which violate
      8+3 constraints, like "config.h.in", or ".emacs"?  */
-  if (strpbrk (filename, "\"*+,;<=>?[\\]|") != 0)
+  if (strpbrk (filename, "\"*+,;<=>?[\\]|") != NULL)
     return filename;
 
   df = dos_filename;
@@ -105,7 +105,7 @@ dosify (const char *filename)
     ++filename;
   if (*filename == '.')
     return filename;
-  *df = 0;
+  *df = '\0';
   return dos_filename;
 }
 #endif /* __MSDOS__ */
@@ -125,8 +125,8 @@ downcase (const char *filename)
   static PATH_VAR (new_filename);
   char *df;
 
-  if (filename == 0)
-    return 0;
+  if (filename == NULL)
+    return NULL;
 
   df = new_filename;
   while (*filename != '\0')
@@ -135,7 +135,7 @@ downcase (const char *filename)
       ++filename;
     }
 
-  *df = 0;
+  *df = '\0';
 
   return new_filename;
 }
@@ -203,14 +203,14 @@ vmsstat_dir (const char *name, struct stat *st)
   DIR *dir;
 
   dir = opendir (name);
-  if (dir == 0)
+  if (dir == NULL)
     return -1;
   closedir (dir);
   s = strchr (name, ':');       /* find device */
   if (s)
     {
       /* to keep the compiler happy we said "const char *name", now we cheat */
-      *s++ = 0;
+      *s++ = '\0';
       st->st_dev = (char *)vms_hash (name);
       h = vms_hash (s);
       *(s-1) = ':';
@@ -281,9 +281,10 @@ clear_directory_contents (struct directory_contents *dc)
     {
       --open_directories;
       closedir (dc->dirstream);
-      dc->dirstream = 0;
+      dc->dirstream = NULL;
     }
-  hash_free (&dc->dirfiles, 1);
+  if (dc->dirfiles.ht_vec != NULL)
+    hash_free (&dc->dirfiles, 1);
 
   return NULL;
 }
@@ -610,10 +611,9 @@ find_directory (const char *name)
       dc->counter = command_count;
 
       ENULLLOOP (dc->dirstream, opendir (name));
-      if (dc->dirstream == 0)
-        /* Couldn't open the directory.  Mark this by setting the
-           'files' member to a nil pointer.  */
-        dc->dirfiles.ht_vec = 0;
+      if (dc->dirstream == NULL)
+        /* Couldn't open the directory: mark this by setting files to NULL.  */
+        dc->dirfiles.ht_vec = NULL;
       else
         {
           hash_init (&dc->dirfiles, DIRFILE_BUCKETS,
@@ -623,7 +623,7 @@ find_directory (const char *name)
           if (open_directories == MAX_OPEN_DIRECTORIES)
             /* We have too many directories open already.
                Read the entire directory and then close it.  */
-            dir_contents_file_exists_p (dir, 0);
+            dir_contents_file_exists_p (dir, NULL);
         }
     }
 
@@ -645,7 +645,7 @@ dir_contents_file_exists_p (struct directory *dir,
   int rehash = 0;
 #endif
 
-  if (dc == 0 || dc->dirfiles.ht_vec == 0)
+  if (dc == NULL || dc->dirfiles.ht_vec == NULL)
     /* The directory could not be stat'd or opened.  */
     return 0;
 
@@ -658,10 +658,10 @@ dir_contents_file_exists_p (struct directory *dir,
 #endif
 
 #ifdef __EMX__
-  if (filename != 0)
+  if (filename != NULL)
     _fnlwr (filename); /* lower case for FAT drives */
 #endif
-  if (filename != 0)
+  if (filename != NULL)
     {
       struct dirfile dirfile_key;
 
@@ -680,7 +680,7 @@ dir_contents_file_exists_p (struct directory *dir,
   /* The file was not found in the hashed list.
      Try to read the directory further.  */
 
-  if (dc->dirstream == 0)
+  if (dc->dirstream == NULL)
     {
 #ifdef WINDOWS32
       /*
@@ -692,7 +692,7 @@ dir_contents_file_exists_p (struct directory *dir,
         {
           if ((dc->fs_flags & FS_FAT) != 0)
             {
-              dc->mtime = time ((time_t *) 0);
+              dc->mtime = time (NULL);
               rehash = 1;
             }
           else if (stat (dc->path_key, &st) == 0 && st.st_mtime > dc->mtime)
@@ -725,7 +725,7 @@ dir_contents_file_exists_p (struct directory *dir,
       struct dirfile **dirfile_slot;
 
       ENULLLOOP (d, readdir (dc->dirstream));
-      if (d == 0)
+      if (d == NULL)
         {
           if (errno)
             OSS (fatal, NILF, "readdir %s: %s", dir->name, strerror (errno));
@@ -772,7 +772,7 @@ dir_contents_file_exists_p (struct directory *dir,
           hash_insert_at (&dc->dirfiles, df, dirfile_slot);
         }
       /* Check if the name matches the one we're searching for.  */
-      if (filename != 0 && patheq (d->d_name, filename))
+      if (filename != NULL && patheq (d->d_name, filename))
         return 1;
     }
 
@@ -819,17 +819,17 @@ file_exists_p (const char *name)
 
   dirend = strrchr (name, '/');
 #ifdef VMS
-  if (dirend == 0)
+  if (dirend == NULL)
     {
       dirend = strrchr (name, ']');
       dirend == NULL ? dirend : dirend++;
     }
-  if (dirend == 0)
+  if (dirend == NULL)
     {
       dirend = strrchr (name, '>');
       dirend == NULL ? dirend : dirend++;
     }
-  if (dirend == 0)
+  if (dirend == NULL)
     {
       dirend = strrchr (name, ':');
       dirend == NULL ? dirend : dirend++;
@@ -846,7 +846,7 @@ file_exists_p (const char *name)
       dirend = name + 1;
   }
 #endif /* HAVE_DOS_PATHS */
-  if (dirend == 0)
+  if (dirend == NULL)
 #ifndef _AMIGA
     return dir_file_exists_p (".", name);
 #else /* !AMIGA */
@@ -920,7 +920,7 @@ file_impossible (const char *filename)
       dirend = p + 1;
   }
 #endif /* HAVE_DOS_PATHS */
-  if (dirend == 0)
+  if (dirend == NULL)
 #ifdef _AMIGA
     dir = find_directory ("");
 #else /* !AMIGA */
@@ -957,16 +957,14 @@ file_impossible (const char *filename)
 #endif
     }
 
-  if (dir->contents == 0)
+  if (dir->contents == NULL)
     /* The directory could not be stat'd.  We allocate a contents
        structure for it, but leave it out of the contents hash table.  */
     dir->contents = xcalloc (sizeof (struct directory_contents));
 
-  if (dir->contents->dirfiles.ht_vec == 0)
-    {
-      hash_init (&dir->contents->dirfiles, DIRFILE_BUCKETS,
-                 dirfile_hash_1, dirfile_hash_2, dirfile_hash_cmp);
-    }
+  if (dir->contents->dirfiles.ht_vec == NULL)
+    hash_init (&dir->contents->dirfiles, DIRFILE_BUCKETS,
+               dirfile_hash_1, dirfile_hash_2, dirfile_hash_cmp);
 
   /* Make a new entry and put it in the table.  */
 
@@ -1018,7 +1016,7 @@ file_impossible_p (const char *filename)
       dirend = filename + 1;
   }
 #endif /* HAVE_DOS_PATHS */
-  if (dirend == 0)
+  if (dirend == NULL)
 #ifdef _AMIGA
     dir = find_directory ("")->contents;
 #else /* !AMIGA */
@@ -1055,7 +1053,7 @@ file_impossible_p (const char *filename)
 #endif
     }
 
-  if (dir == 0 || dir->dirfiles.ht_vec == 0)
+  if (dir == NULL || dir->dirfiles.ht_vec == NULL)
     /* There are no files entered for this directory.  */
     return 0;
 
@@ -1112,9 +1110,9 @@ print_dir_data_base (void)
       struct directory *dir = *dir_slot;
       if (! HASH_VACANT (dir))
         {
-          if (dir->contents == 0)
+          if (dir->contents == NULL)
             printf (_("# %s: could not be stat'd.\n"), dir->name);
-          else if (dir->contents->dirfiles.ht_vec == 0)
+          else if (dir->contents->dirfiles.ht_vec == NULL)
 #ifdef WINDOWS32
             printf (_("# %s (key %s, mtime %s): could not be opened.\n"),
                     dir->name, dir->contents->path_key,
@@ -1171,7 +1169,7 @@ print_dir_data_base (void)
               else
                 printf ("%u", im);
               fputs (_(" impossibilities"), stdout);
-              if (dir->contents->dirstream == 0)
+              if (dir->contents->dirstream == NULL)
                 puts (".");
               else
                 puts (_(" so far."));
@@ -1214,15 +1212,15 @@ open_dirstream (const char *directory)
   struct dirstream *new;
   struct directory *dir = find_directory (directory);
 
-  if (dir->contents == 0 || dir->contents->dirfiles.ht_vec == 0)
+  if (dir->contents == NULL || dir->contents->dirfiles.ht_vec == NULL)
     /* DIR->contents is nil if the directory could not be stat'd.
        DIR->contents->dirfiles is nil if it could not be opened.  */
-    return 0;
+    return NULL;
 
   /* Read all the contents of the directory now.  There is no benefit
      in being lazy, since glob will want to see every file anyway.  */
 
-  dir_contents_file_exists_p (dir, 0);
+  dir_contents_file_exists_p (dir, NULL);
 
   new = xmalloc (sizeof (struct dirstream));
   new->contents = dir->contents;
@@ -1276,7 +1274,7 @@ read_dirstream (__ptr_t stream)
         }
     }
 
-  return 0;
+  return NULL;
 }
 
 /* On 64 bit ReliantUNIX (5.44 and above) in LFS mode, stat() is actually a