Subversion Repositories test_project

/*

 * Helper function for splitting a string into an argv-like array.

 */

#include <linux/kernel.h>

#include <linux/ctype.h>

#include <linux/slab.h>

#include <linux/module.h>

static const char *skip_sep(const char *cp)

{

        while (*cp && isspace(*cp))

                cp++;

        return cp;

}

static const char *skip_arg(const char *cp)

{

        while (*cp && !isspace(*cp))

                cp++;

        return cp;

}

static int count_argc(const char *str)

{

        int count = 0;

        while (*str) {

                str = skip_sep(str);

                if (*str) {

                        count++;

                        str = skip_arg(str);

                }

        }

        return count;

}

/**

 * argv_free - free an argv

 * @argv - the argument vector to be freed

 *

 * Frees an argv and the strings it points to.

 */

void argv_free(char **argv)

{

        char **p;

        for (p = argv; *p; p++)

                kfree(*p);

        kfree(argv);

}

EXPORT_SYMBOL(argv_free);

/**

 * argv_split - split a string at whitespace, returning an argv

 * @gfp: the GFP mask used to allocate memory

 * @str: the string to be split

 * @argcp: returned argument count

 *

 * Returns an array of pointers to strings which are split out from

 * @str.  This is performed by strictly splitting on white-space; no

 * quote processing is performed.  Multiple whitespace characters are

 * considered to be a single argument separator.  The returned array

 * is always NULL-terminated.  Returns NULL on memory allocation

 * failure.

 */

char **argv_split(gfp_t gfp, const char *str, int *argcp)

{

        int argc = count_argc(str);

        char **argv = kzalloc(sizeof(*argv) * (argc+1), gfp);

        char **argvp;

        if (argv == NULL)

                goto out;

        if (argcp)

                *argcp = argc;

        argvp = argv;

        while (*str) {

                str = skip_sep(str);

                if (*str) {

                        const char *p = str;

                        char *t;

                        str = skip_arg(str);

                        t = kstrndup(p, str-p, gfp);

                        if (t == NULL)

                                goto fail;

                        *argvp++ = t;

                }

        }

        *argvp = NULL;

  out:

        return argv;

  fail:

        argv_free(argv);

        return NULL;

}

EXPORT_SYMBOL(argv_split);