Prepare for radical source tree reorganization. zack/build-layout-experiment

All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).

1 files changed, 172 insertions, 0 deletions

diff --git a/REORG.TODO/string/envz.c b/REORG.TODO/string/envz.c
new file mode 100644
index 0000000000..02fb5cc28a
--- /dev/null
+++ b/REORG.TODO/string/envz.c
@@ -0,0 +1,172 @@
+/* Routines for dealing with '\0' separated environment vectors
+   Copyright (C) 1995-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Written by Miles Bader <miles@gnu.org>
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <malloc.h>
+#include <string.h>
+
+#include <envz.h>
+
+/* The character separating names from values in an envz.  */
+#define SEP '='
+
+/* Returns a pointer to the entry in ENVZ for NAME, or 0 if there is none.
+   If NAME contains the separator character, only the portion before it is
+   used in the comparison.  */
+char *
+envz_entry (const char *envz, size_t envz_len, const char *name)
+{
+  while (envz_len)
+    {
+      const char *p = name;
+      const char *entry = envz;	/* Start of this entry. */
+
+      /* See how far NAME and ENTRY match.  */
+      while (envz_len && *p == *envz && *p && *p != SEP)
+	p++, envz++, envz_len--;
+
+      if ((*envz == '\0' || *envz == SEP) && (*p == '\0' || *p == SEP))
+	/* Bingo! */
+	return (char *) entry;
+
+      /* No match, skip to the next entry.  */
+      while (envz_len && *envz)
+	envz++, envz_len--;
+      if (envz_len)
+	envz++, envz_len--;	/* skip '\0' */
+    }
+
+  return 0;
+}
+libc_hidden_def (envz_entry)
+
+/* Returns a pointer to the value portion of the entry in ENVZ for NAME, or 0
+   if there is none.  */
+char *
+envz_get (const char *envz, size_t envz_len, const char *name)
+{
+  char *entry = envz_entry (envz, envz_len, name);
+  if (entry)
+    {
+      while (*entry && *entry != SEP)
+	entry++;
+      if (*entry)
+	entry++;
+      else
+	entry = 0;		/* A null entry.  */
+    }
+  return entry;
+}
+
+/* Remove the entry for NAME from ENVZ & ENVZ_LEN, if any.  */
+void
+envz_remove (char **envz, size_t *envz_len, const char *name)
+{
+  char *entry = envz_entry (*envz, *envz_len, name);
+  if (entry)
+    argz_delete (envz, envz_len, entry);
+}
+libc_hidden_def (envz_remove)
+
+/* Adds an entry for NAME with value VALUE to ENVZ & ENVZ_LEN.  If an entry
+   with the same name already exists in ENVZ, it is removed.  If VALUE is
+   NULL, then the new entry will a special null one, for which envz_get will
+   return NULL, although envz_entry will still return an entry; this is handy
+   because when merging with another envz, the null entry can override an
+   entry in the other one.  Null entries can be removed with envz_strip ().  */
+error_t
+envz_add (char **envz, size_t *envz_len, const char *name, const char *value)
+{
+  envz_remove (envz, envz_len, name);
+
+  if (value)
+    /* Add the new value, if there is one.  */
+    {
+      size_t name_len = strlen (name);
+      size_t value_len = strlen (value);
+      size_t old_envz_len = *envz_len;
+      size_t new_envz_len = old_envz_len + name_len + 1 + value_len + 1;
+      char *new_envz = realloc (*envz, new_envz_len);
+
+      if (new_envz)
+	{
+	  memcpy (new_envz + old_envz_len, name, name_len);
+	  new_envz[old_envz_len + name_len] = SEP;
+	  memcpy (new_envz + old_envz_len + name_len + 1, value, value_len);
+	  new_envz[new_envz_len - 1] = 0;
+
+	  *envz = new_envz;
+	  *envz_len = new_envz_len;
+
+	  return 0;
+	}
+      else
+	return ENOMEM;
+    }
+  else
+    /* Add a null entry.  */
+    return __argz_add (envz, envz_len, name);
+}
+
+/* Adds each entry in ENVZ2 to ENVZ & ENVZ_LEN, as if with envz_add().  If
+   OVERRIDE is true, then values in ENVZ2 will supersede those with the same
+   name in ENV, otherwise not.  */
+error_t
+envz_merge (char **envz, size_t *envz_len, const char *envz2,
+	    size_t envz2_len, int override)
+{
+  error_t err = 0;
+
+  while (envz2_len && ! err)
+    {
+      char *old = envz_entry (*envz, *envz_len, envz2);
+      size_t new_len = strlen (envz2) + 1;
+
+      if (! old)
+	err = __argz_append (envz, envz_len, envz2, new_len);
+      else if (override)
+	{
+	  argz_delete (envz, envz_len, old);
+	  err = __argz_append (envz, envz_len, envz2, new_len);
+	}
+
+      envz2 += new_len;
+      envz2_len -= new_len;
+    }
+
+  return err;
+}
+
+/* Remove null entries.  */
+void
+envz_strip (char **envz, size_t *envz_len)
+{
+  char *entry = *envz;
+  size_t left = *envz_len;
+  while (left)
+    {
+      size_t entry_len = strlen (entry) + 1;
+      left -= entry_len;
+      if (! strchr (entry, SEP))
+	/* Null entry. */
+	memmove (entry, entry + entry_len, left);
+      else
+	entry += entry_len;
+    }
+  *envz_len = entry - *envz;
+}