Remove scandir() requirement in pg_upgrade; instead just use readdir()

--- we were not using the scandir pattern filtering anyway.  This also
removes the scandir requirement in configure.

Author: bmomjian

configure

@@ -18987,8 +18987,7 @@ fi
 
 
 
-
-for ac_func in cbrt dlopen fcvt fdatasync getifaddrs getpeerucred getrlimit memmove poll pstat readlink scandir setproctitle setsid sigprocmask symlink sysconf towlower utime utimes waitpid wcstombs wcstombs_l
+for ac_func in cbrt dlopen fcvt fdatasync getifaddrs getpeerucred getrlimit memmove poll pstat readlink setproctitle setsid sigprocmask symlink sysconf towlower utime utimes waitpid wcstombs wcstombs_l
 do
 as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
 { $as_echo "$as_me:$LINENO: checking for $ac_func" >&5

configure.in

@@ -1193,7 +1193,7 @@ PGAC_VAR_INT_TIMEZONE
 AC_FUNC_ACCEPT_ARGTYPES
 PGAC_FUNC_GETTIMEOFDAY_1ARG
 
-AC_CHECK_FUNCS([cbrt dlopen fcvt fdatasync getifaddrs getpeerucred getrlimit memmove poll pstat readlink scandir setproctitle setsid sigprocmask symlink sysconf towlower utime utimes waitpid wcstombs wcstombs_l])
+AC_CHECK_FUNCS([cbrt dlopen fcvt fdatasync getifaddrs getpeerucred getrlimit memmove poll pstat readlink setproctitle setsid sigprocmask symlink sysconf towlower utime utimes waitpid wcstombs wcstombs_l])
 
 AC_REPLACE_FUNCS(fseeko)
 case $host_os in

contrib/pg_upgrade/file.c

@@ -21,12 +21,6 @@ static int	copy_file(const char *fromfile, const char *tofile, bool force);
 static int	win32_pghardlink(const char *src, const char *dst);
 #endif
 
-#ifndef HAVE_SCANDIR
-static int pg_scandir_internal(const char *dirname,
-					struct dirent *** namelist,
-					int (*selector) (const struct dirent *));
-#endif
-
 
 /*
  * copyAndUpdateFile()
@@ -228,59 +222,18 @@ copy_file(const char *srcfile, const char *dstfile, bool force)
 
 
 /*
- * pg_scandir()
- *
- * Wrapper for portable scandir functionality
- */
-int
-pg_scandir(const char *dirname,
-		   struct dirent *** namelist,
-		   int (*selector) (const struct dirent *))
-{
-#ifndef HAVE_SCANDIR
-	return pg_scandir_internal(dirname, namelist, selector);
-
-	/*
-	 * scandir() is originally from BSD 4.3, which had the third argument as
-	 * non-const. Linux and other C libraries have updated it to use a const.
-	 * http://unix.derkeiler.com/Mailing-Lists/FreeBSD/questions/2005-12/msg002
-	 * 14.html
-	 *
-	 * Here we try to guess which libc's need const, and which don't. The net
-	 * goal here is to try to suppress a compiler warning due to a prototype
-	 * mismatch of const usage. Ideally we would do this via autoconf, but
-	 * autoconf doesn't have a suitable builtin test and it seems overkill to
-	 * add one just to avoid a warning.
-	 */
-#elif defined(__FreeBSD__) || defined(__bsdi__) || defined(__darwin__) || defined(__OpenBSD__)
-	/* no const */
-	return scandir(dirname, namelist, (int (*) (struct dirent *)) selector, NULL);
-#else
-	/* use const */
-	return scandir(dirname, namelist, selector, NULL);
-#endif
-}
-
-
-#ifndef HAVE_SCANDIR
-/*
- * pg_scandir_internal()
- *
- * Implement our own scandir() on platforms that don't have it.
+ * load_directory()
  *
  * Returns count of files that meet the selection criteria coded in
  * the function pointed to by selector.  Creates an array of pointers
  * to dirent structures.  Address of array returned in namelist.
  *
  * Note that the number of dirent structures needed is dynamically
  * allocated using realloc.  Realloc can be inefficient if invoked a
- * large number of times.  Its use in pg_upgrade is to find filesystem
- * filenames that have extended beyond the initial segment (file.1,
- * .2, etc.) and should therefore be invoked a small number of times.
+ * large number of times.
  */
-static int
-pg_scandir_internal(const char *dirname,
-		 struct dirent *** namelist, int (*selector) (const struct dirent *))
+int
+load_directory(const char *dirname, struct dirent ***namelist)
 {
 	DIR		   *dirdesc;
 	struct dirent *direntry;
@@ -295,42 +248,37 @@ pg_scandir_internal(const char *dirname,
 
 	while ((direntry = readdir(dirdesc)) != NULL)
 	{
-		/* Invoke the selector function to see if the direntry matches */
-		if (!selector || (*selector) (direntry))
-		{
-			count++;
+		count++;
 
-			*namelist = (struct dirent **) realloc((void *) (*namelist),
-						(size_t) ((name_num + 1) * sizeof(struct dirent *)));
+		*namelist = (struct dirent **) realloc((void *) (*namelist),
+					(size_t) ((name_num + 1) * sizeof(struct dirent *)));
 
-			if (*namelist == NULL)
-			{
-				closedir(dirdesc);
-				return -1;
-			}
+		if (*namelist == NULL)
+		{
+			closedir(dirdesc);
+			return -1;
+		}
 
-			entrysize = sizeof(struct dirent) - sizeof(direntry->d_name) +
-				strlen(direntry->d_name) + 1;
+		entrysize = sizeof(struct dirent) - sizeof(direntry->d_name) +
+			strlen(direntry->d_name) + 1;
 
-			(*namelist)[name_num] = (struct dirent *) malloc(entrysize);
+		(*namelist)[name_num] = (struct dirent *) malloc(entrysize);
 
-			if ((*namelist)[name_num] == NULL)
-			{
-				closedir(dirdesc);
-				return -1;
-			}
+		if ((*namelist)[name_num] == NULL)
+		{
+			closedir(dirdesc);
+			return -1;
+		}
 
-			memcpy((*namelist)[name_num], direntry, entrysize);
+		memcpy((*namelist)[name_num], direntry, entrysize);
 
-			name_num++;
-		}
+		name_num++;
 	}
 
 	closedir(dirdesc);
 
 	return count;
 }
-#endif
 
 
 void

contrib/pg_upgrade/pg_upgrade.h

@@ -333,8 +333,7 @@ const char *setupPageConverter(pageCnvCtx **result);
 typedef void *pageCnvCtx;
 #endif
 
-int pg_scandir(const char *dirname, struct dirent *** namelist,
-		   int (*selector) (const struct dirent *));
+int load_directory(const char *dirname, struct dirent ***namelist);
 const char *copyAndUpdateFile(pageCnvCtx *pageConverter, const char *src,
 				  const char *dst, bool force);
 const char *linkAndUpdateFile(pageCnvCtx *pageConverter, const char *src,

contrib/pg_upgrade/relfilenode.c

@@ -160,7 +160,7 @@ transfer_single_new_db(pageCnvCtx *pageConverter,
 			}
 
 			snprintf(old_dir, sizeof(old_dir), "%s", maps[mapnum].old_dir);
-			numFiles = pg_scandir(old_dir, &namelist, NULL);
+			numFiles = load_directory(old_dir, &namelist);
 		}
 
 		/* Copying files might take some time, so give feedback. */