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-rw-r--r--string/argz-insert.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/string/argz-insert.c b/string/argz-insert.c
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+++ b/string/argz-insert.c
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+/* Routines for dealing with '\0' separated arg vectors.
+
+ Copyright (C) 1995, 1996 Free Software Foundation, Inc.
+
+ Written by Miles Bader <miles@gnu.ai.mit.edu>
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2, or (at
+ your option) any later version.
+
+ This program 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#include <argz.h>
+#include <string.h>
+#include <stdlib.h>
+
+/* Insert ENTRY into ARGZ & ARGZ_LEN before BEFORE, which should be an
+ existing entry in ARGZ; if BEFORE is NULL, ENTRY is appended to the end.
+ Since ARGZ's first entry is the same as ARGZ, argz_insert (ARGZ, ARGZ_LEN,
+ ARGZ, ENTRY) will insert ENTRY at the beginning of ARGZ. If BEFORE is not
+ in ARGZ, EINVAL is returned, else if memory can't be allocated for the new
+ ARGZ, ENOMEM is returned, else 0. */
+error_t
+__argz_insert (char **argz, size_t *argz_len, char *before, const char *entry)
+{
+ if (! before)
+ return __argz_add (argz, argz_len, entry);
+
+ if (before < *argz || before >= *argz + *argz_len)
+ return EINVAL;
+
+ if (before > *argz)
+ /* Make sure before is actually the beginning of an entry. */
+ while (before[-1])
+ before--;
+
+ {
+ size_t after_before = *argz_len - (before - *argz);
+ size_t entry_len = strlen (entry) + 1;
+ size_t new_argz_len = *argz_len + entry_len;
+ char *new_argz = realloc (*argz, new_argz_len);
+
+ if (new_argz)
+ {
+ before = new_argz + (before - *argz);
+ memcpy (before + entry_len, before, after_before);
+ memcpy (before, entry, entry_len);
+ *argz = new_argz;
+ *argz_len = new_argz_len;
+ return 0;
+ }
+ else
+ return ENOMEM;
+ }
+}
+weak_alias (__argz_insert, argz_insert)