1  /*
 2   *
 3   * Copyright (C) 2008 coresystems GmbH
 4   *
 5   * Redistribution and use in source and binary forms, with or without
 6   * modification, are permitted provided that the following conditions
 7   * are met:
 8   * 1. Redistributions of source code must retain the above copyright
 9   *    notice, this list of conditions and the following disclaimer.
10   * 2. Redistributions in binary form must reproduce the above copyright
11   *    notice, this list of conditions and the following disclaimer in the
12   *    documentation and/or other materials provided with the distribution.
13   * 3. The name of the author may not be used to endorse or promote products
14   *    derived from this software without specific prior written permission.
15   *
16   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19   * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26   * SUCH DAMAGE.
27   */
28  
29  /**
30   * @file libc/readline.c
31   * Simple readline implementation
32   */
33  
34  #include <libpayload.h>
35  #include <getopt.h>
36  
37  /* We don't want to waste malloc on this, so we live with a small
38   * fixed size array
39   */
40  char *string_argv[MAX_ARGS];
41  int string_argc;
42  
43  /**
44   * Take a string and make char *argv[] and int argc from it.
45   *
46   * This function allows the user to use getopt on an arbitrary string.
47   *
48   * global variables valid after a successful run of string_to_args():
49   *   string_argc pointer to number of arguments
50   *   string_argv pointer to argument list.
51   *
52   * @param caller to be used as argv[0] (may be NULL to ignore)
53   * @param string to process
54   * @return 0 if no error occurred.
55   */
56  int string_to_args(char *caller, char *string)
57  {
58  	int i = 0;
59  
60  	if (caller)
61  		string_argv[i++] = caller;
62  
63  	if (*string)
64  		string_argv[i++] = string;
65  
66  	/* Terminate if the string ends */
67  	while (string && *string) {
68  		/* whitespace occurred? */
69  		if ((*string == ' ') || (*string == '\t')) {
70  			/* skip all whitespace (and null it) */
71  			while (*string == ' ' || *string == '\t')
72  				*string++ = 0;
73  			/* if our ugly static array is big enough, store
74  			 * argument to string_argv[]
75  			 */
76  			if (i < MAX_ARGS)
77  				string_argv[i++] = string;
78  		}
79  		string++;
80  	}
81  
82  	/* prevent array from overflowing */
83  	string_argc = (i <= MAX_ARGS) ? i : MAX_ARGS;
84  
85  	/* and return whether there was an overflow */
86  	return (i <= MAX_ARGS) ? 0 : 1;
87  }