toolbox: Add setfattr

TOOLS += r

endif

TOOLS += setfattr

ALL_TOOLS = $(TOOLS)

ALL_TOOLS += \

	cp \

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <sys/types.h>

extern int setxattr(const char *, const char *, const void *, size_t, int);

static int usage(const char *s)

{

    fprintf(stderr, "Usage: %s -n name -v value pathname\n", s);

    fprintf(stderr, "  -n name      name of the extended attribute to set\n");

    fprintf(stderr, "  -v value     new value of the attribute\n");

    fprintf(stderr, "  -h           display this help and exit\n");

    exit(10);

}

int setfattr_main(int argc, char **argv)

{

    int i;

    char *name = NULL;

    char *valuestr = NULL;

    unsigned long long value = 0;

    size_t valuelen = 0;

    for (;;) {

        int ret;

        ret = getopt(argc, argv, "hn:v:");

        if (ret < 0)

            break;

        switch(ret) {

            case 'h':

                usage(argv[0]);

                break;

            case 'n':

                name = optarg;

                break;

            case 'v':

                valuestr = optarg;

                break;

        }

    }

    if (!name || !valuestr || optind == argc)

        usage(argv[0]);

    /*

     * We are being super lazy here, since setxattr can take an arbitrary

     * amount of binary data.  We assume that the value is numerical and

     * not longer than 8 bytes.  strtoull() detects the numeric base from

     * the string prefix (0x for hexidecimal or 0 for octal).  We also

     * ignore endianness problems because it all works out fine on little

     * endian.  Hey, it's toolbox!

     */

    value = strtoull(valuestr, NULL, 0);

    while ((value >> (valuelen * 8)))

        valuelen++;

    for (i = optind ; i < argc ; i++)

        setxattr(argv[i], name, &value, valuelen, 0);

    return 0;

}