argz_insert.c

来自「cygwin, 著名的在win32下模拟unix操作系统的东东」· C语言 代码 · 共 39 行

/* Copyright (C) 2002 by  Red Hat, Incorporated. All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software
 * is freely granted, provided that this notice is preserved.
 */

#include <errno.h>
#include <sys/types.h>
#include <string.h>
#include <stdlib.h>
#include <argz.h>

error_t
argz_insert (char **argz, size_t *argz_len, char *before, const char *entry)
{
  int len = 0;

  if (before == NULL)
    argz_add(argz, argz_len, entry);

  if (before < *argz || before >= *argz + *argz_len)
    return EINVAL;

  while (before != *argz && before[-1])
    before--;

  len = strlen(entry) + 1;

  if(!(*argz = (char *)realloc(*argz, *argz_len + len)))
    return ENOMEM;
  
  memmove(before + len, before, *argz + *argz_len - before);
  memcpy(before, entry, len);

  *argz_len += len;

  return 0;
}