[thirdparty/util-linux.git] / lib / strutils.c

/*
 * No copyright is claimed.  This code is in the public domain; do with
 * it what you wish.
 *
 * Authors: Karel Zak <kzak@redhat.com> [2010]
 *          Davidlohr Bueso <dave@gnu.org> [2010]
 */
#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include <ctype.h>
#include <errno.h>
#include <sys/stat.h>
#include <string.h>
#include <strings.h>
#include <assert.h>

#include "c.h"
#include "nls.h"
#include "strutils.h"
#include "bitops.h"
#include "pathnames.h"

static int STRTOXX_EXIT_CODE = EXIT_FAILURE;

void strutils_set_exitcode(int ex) {
        STRTOXX_EXIT_CODE = ex;
}

static int do_scale_by_power (uintmax_t *x, int base, int power)
{
        while (power--) {
                if (UINTMAX_MAX / base < *x)
                        return -ERANGE;
                *x *= base;
        }
        return 0;
}

/*
 * strtosize() - convert string to size (uintmax_t).
 *
 * Supported suffixes:
 *
 * XiB or X for 2^N
 *     where X = {K,M,G,T,P,E,Z,Y}
 *        or X = {k,m,g,t,p,e}  (undocumented for backward compatibility only)
 * for example:
 *              10KiB   = 10240
 *              10K     = 10240
 *
 * XB for 10^N
 *     where X = {K,M,G,T,P,E,Z,Y}
 * for example:
 *              10KB    = 10000
 *
 * The optional 'power' variable returns number associated with used suffix
 * {K,M,G,T,P,E,Z,Y}  = {1,2,3,4,5,6,7,8}.
 *
 * The function also supports decimal point, for example:
 *              0.5MB   = 500000
 *              0.5MiB  = 512000
 *
 * Note that the function does not accept numbers with '-' (negative sign)
 * prefix.
 */
int ul_parse_size(const char *str, uintmax_t *res, int *power)
{
        const char *p;
        char *end;
        uintmax_t x, frac = 0;
        int base = 1024, rc = 0, pwr = 0, frac_zeros = 0;

        static const char *suf  = "KMGTPEZY";
        static const char *suf2 = "kmgtpezy";
        const char *sp;

        *res = 0;

        if (!str || !*str) {
                rc = -EINVAL;
                goto err;
        }

        /* Only positive numbers are acceptable
         *
         * Note that this check is not perfect, it would be better to
         * use lconv->negative_sign. But coreutils use the same solution,
         * so it's probably good enough...
         */
        p = str;
        while (isspace((unsigned char) *p))
                p++;
        if (*p == '-') {
                rc = -EINVAL;
                goto err;
        }

        errno = 0, end = NULL;
        x = strtoumax(str, &end, 0);

        if (end == str ||
            (errno != 0 && (x == UINTMAX_MAX || x == 0))) {
                rc = errno ? -errno : -EINVAL;
                goto err;
        }
        if (!end || !*end)
                goto done;                      /* without suffix */
        p = end;

        /*
         * Check size suffixes
         */
check_suffix:
        if (*(p + 1) == 'i' && (*(p + 2) == 'B' || *(p + 2) == 'b') && !*(p + 3))
                base = 1024;                    /* XiB, 2^N */
        else if ((*(p + 1) == 'B' || *(p + 1) == 'b') && !*(p + 2))
                base = 1000;                    /* XB, 10^N */
        else if (*(p + 1)) {
                struct lconv const *l = localeconv();
                const char *dp = l ? l->decimal_point : NULL;
                size_t dpsz = dp ? strlen(dp) : 0;

                if (frac == 0 && *p && dp && strncmp(dp, p, dpsz) == 0) {
                        const char *fstr = p + dpsz;

                        for (p = fstr; *p == '0'; p++)
                                frac_zeros++;
                        fstr = p;
                        if (isdigit(*fstr)) {
                                errno = 0, end = NULL;
                                frac = strtoumax(fstr, &end, 0);
                                if (end == fstr ||
                                    (errno != 0 && (frac == UINTMAX_MAX || frac == 0))) {
                                        rc = errno ? -errno : -EINVAL;
                                        goto err;
                                }
                        } else
                                end = (char *) p;

                        if (frac && (!end  || !*end)) {
                                rc = -EINVAL;
                                goto err;               /* without suffix, but with frac */
                        }
                        p = end;
                        goto check_suffix;
                }
                rc = -EINVAL;
                goto err;                       /* unexpected suffix */
        }

        sp = strchr(suf, *p);
        if (sp)
                pwr = (sp - suf) + 1;
        else {
                sp = strchr(suf2, *p);
                if (sp)
                        pwr = (sp - suf2) + 1;
                else {
                        rc = -EINVAL;
                        goto err;
                }
        }

        rc = do_scale_by_power(&x, base, pwr);
        if (power)
                *power = pwr;
        if (frac && pwr) {
                int i;
                uintmax_t frac_div = 10, frac_poz = 1, frac_base = 1;

                /* mega, giga, ... */
                do_scale_by_power(&frac_base, base, pwr);

                /* maximal divisor for last digit (e.g. for 0.05 is
                 * frac_div=100, for 0.054 is frac_div=1000, etc.)
                 *
                 * Reduce frac if too large.
                 */
                while (frac_div < frac) {
                        if (frac_div <= UINTMAX_MAX/10)
                                frac_div *= 10;
                        else
                                frac /= 10;
                }

                /* 'frac' is without zeros (5 means 0.5 as well as 0.05) */
                for (i = 0; i < frac_zeros; i++) {
                        if (frac_div <= UINTMAX_MAX/10)
                                frac_div *= 10;
                        else
                                frac /= 10;
                }

                /*
                 * Go backwardly from last digit and add to result what the
                 * digit represents in the frac_base. For example 0.25G
                 *
                 *  5 means 1GiB / (100/5)
                 *  2 means 1GiB / (10/2)
                 */
                do {
                        unsigned int seg = frac % 10;            /* last digit of the frac */
                        uintmax_t seg_div = frac_div / frac_poz; /* what represents the segment 1000, 100, .. */

                        frac /= 10;     /* remove last digit from frac */
                        frac_poz *= 10;

                        if (seg && seg_div / seg)
                                x += frac_base / (seg_div / seg);
                } while (frac);
        }
done:
        *res = x;
err:
        if (rc < 0)
                errno = -rc;
        return rc;
}

int strtosize(const char *str, uintmax_t *res)
{
        return ul_parse_size(str, res, NULL);
}

int isdigit_strend(const char *str, const char **end)
{
        const char *p;

        for (p = str; p && *p && isdigit((unsigned char) *p); p++);

        if (end)
                *end = p;
        return p && p > str && !*p;
}

int isxdigit_strend(const char *str, const char **end)
{
        const char *p;

        for (p = str; p && *p && isxdigit((unsigned char) *p); p++);

        if (end)
                *end = p;

        return p && p > str && !*p;
}

/*
 *  For example: ul_parse_switch(argv[i], "on", "off",  "yes", "no",  NULL);
 */
int ul_parse_switch(const char *arg, ...)
{
        const char *a, *b;
        va_list ap;

        va_start(ap, arg);
        do {
                a = va_arg(ap, char *);
                if (!a)
                        break;
                b = va_arg(ap, char *);
                if (!b)
                        break;

                if (strcmp(arg, a) == 0) {
                        va_end(ap);
                        return 1;
                }

                if (strcmp(arg, b) == 0) {
                        va_end(ap);
                        return 0;
                }
        } while (1);
        va_end(ap);

        errx(STRTOXX_EXIT_CODE, _("unsupported argument: %s"), arg);
}

#ifndef HAVE_MEMPCPY
void *mempcpy(void *restrict dest, const void *restrict src, size_t n)
{
    return ((char *)memcpy(dest, src, n)) + n;
}
#endif

#ifndef HAVE_STRNLEN
size_t strnlen(const char *s, size_t maxlen)
{
        size_t i;

        for (i = 0; i < maxlen; i++) {
                if (s[i] == '\0')
                        return i;
        }
        return maxlen;
}
#endif

#ifndef HAVE_STRNCHR
char *strnchr(const char *s, size_t maxlen, int c)
{
        for (; maxlen-- && *s != '\0'; ++s)
                if (*s == (char)c)
                        return (char *)s;
        return NULL;
}
#endif

#ifndef HAVE_STRNDUP
char *strndup(const char *s, size_t n)
{
        size_t len = strnlen(s, n);
        char *new = malloc((len + 1) * sizeof(char));
        if (!new)
                return NULL;
        new[len] = '\0';
        return (char *) memcpy(new, s, len);
}
#endif

/*
 * convert strings to numbers; returns <0 on error, and 0 on success
 */
int ul_strtos64(const char *str, int64_t *num, int base)
{
        char *end = NULL;

        if (str == NULL || *str == '\0')
                return -(errno = EINVAL);

        errno = 0;
        *num = (int64_t) strtoimax(str, &end, base);

        if (errno != 0)
                return -errno;
        if (str == end || (end && *end))
                return -(errno = EINVAL);
        return 0;
}

int ul_strtou64(const char *str, uint64_t *num, int base)
{
        char *end = NULL;
        int64_t tmp;

        if (str == NULL || *str == '\0')
                return -(errno = EINVAL);

        /* we need to ignore negative numbers, note that for invalid negative
         * number strtoimax() returns negative number too, so we do not
         * need to check errno here */
        errno = 0;
        tmp = (int64_t) strtoimax(str, &end, base);
        if (tmp < 0)
                errno = ERANGE;
        else {
                errno = 0;
                *num = strtoumax(str, &end, base);
        }

        if (errno != 0)
                return -errno;
        if (str == end || (end && *end))
                return -(errno = EINVAL);
        return 0;
}

int ul_strtos32(const char *str, int32_t *num, int base)
{
        int64_t tmp;
        int rc;

        rc = ul_strtos64(str, &tmp, base);
        if (rc == 0 && (tmp < INT32_MIN || tmp > INT32_MAX))
                rc = -(errno = ERANGE);
        if (rc == 0)
                *num = (int32_t) tmp;
        return rc;
}

int ul_strtou32(const char *str, uint32_t *num, int base)
{
        uint64_t tmp;
        int rc;

        rc = ul_strtou64(str, &tmp, base);
        if (rc == 0 && tmp > UINT32_MAX)
                rc = -(errno = ERANGE);
        if (rc == 0)
                *num = (uint32_t) tmp;
        return rc;
}

int ul_strtou16(const char *str, uint16_t *num, int base)
{
        uint64_t tmp;
        int rc;

        rc = ul_strtou64(str, &tmp, base);
        if (rc == 0 && tmp > UINT16_MAX)
                rc = -(errno = ERANGE);
        if (rc == 0)
                *num = (uint16_t) tmp;
        return rc;
}

/*
 * Convert strings to numbers in defined range and print message on error.
 *
 * These functions are used when we read input from users (getopt() etc.). It's
 * better to consolidate the code and keep it all based on 64-bit numbers than
 * implement it for 32 and 16-bit numbers too.
 */
int64_t str2num_or_err(const char *str, int base, const char *errmesg,
                             int64_t low, int64_t up)
{
        int64_t num = 0;
        int rc;

        rc = ul_strtos64(str, &num, base);
        if (rc == 0 && ((low && num < low) || (up && num > up)))
                rc = -(errno = ERANGE);

        if (rc) {
                if (errno == ERANGE)
                        err(STRTOXX_EXIT_CODE, "%s: '%s'", errmesg, str);
                errx(STRTOXX_EXIT_CODE, "%s: '%s'", errmesg, str);
        }
        return num;
}

uint64_t str2unum_or_err(const char *str, int base, const char *errmesg, uint64_t up)
{
        uint64_t num = 0;
        int rc;

        rc = ul_strtou64(str, &num, base);
        if (rc == 0 && (up && num > up))
                rc = -(errno = ERANGE);

        if (rc) {
                if (errno == ERANGE)
                        err(STRTOXX_EXIT_CODE, "%s: '%s'", errmesg, str);
                errx(STRTOXX_EXIT_CODE, "%s: '%s'", errmesg, str);
        }
        return num;
}

double strtod_or_err(const char *str, const char *errmesg)
{
        double num;
        char *end = NULL;

        errno = 0;
        if (str == NULL || *str == '\0')
                goto err;
        num = strtod(str, &end);

        if (errno || str == end || (end && *end))
                goto err;

        return num;
err:
        if (errno == ERANGE)
                err(STRTOXX_EXIT_CODE, "%s: '%s'", errmesg, str);

        errx(STRTOXX_EXIT_CODE, "%s: '%s'", errmesg, str);
}

int ul_strtold(const char *str, long double *num)
{
        char *end = NULL;

        errno = 0;
        if (str == NULL || *str == '\0')
                return -(errno = EINVAL);
        *num = strtold(str, &end);

        if (errno != 0)
                return -errno;
        if (str == end || (end && *end))
                return -(errno = EINVAL);
        return 0;
}

long double strtold_or_err(const char *str, const char *errmesg)
{
        long double num = 0;

        if (ul_strtold(str, &num) == 0)
                return num;
        if (errno == ERANGE)
                err(STRTOXX_EXIT_CODE, "%s: '%s'", errmesg, str);

        errx(STRTOXX_EXIT_CODE, "%s: '%s'", errmesg, str);
}

uintmax_t strtosize_or_err(const char *str, const char *errmesg)
{
        uintmax_t num;

        if (strtosize(str, &num) == 0)
                return num;

        if (errno)
                err(STRTOXX_EXIT_CODE, "%s: '%s'", errmesg, str);

        errx(STRTOXX_EXIT_CODE, "%s: '%s'", errmesg, str);
}


void strtotimeval_or_err(const char *str, struct timeval *tv, const char *errmesg)
{
        long double user_input;

        user_input = strtold_or_err(str, errmesg);
        tv->tv_sec = (time_t) user_input;
        tv->tv_usec = (suseconds_t)((user_input - tv->tv_sec) * 1000000);
}

void strtotimespec_or_err(const char *str, struct timespec *ts, const char *errmesg)
{
        long double user_input;

        user_input = strtold_or_err(str, errmesg);
        ts->tv_sec = (time_t) user_input;
        ts->tv_nsec = (long)((user_input - ts->tv_sec) * 1000000000);
}

time_t strtotime_or_err(const char *str, const char *errmesg)
{
        int64_t user_input;

        user_input = strtos64_or_err(str, errmesg);
        return (time_t) user_input;
}

bool hyperlinkwanted(const char *mode)
{
        if (mode && strcmp(mode, "never") == 0)
                return false;

        if (mode && strcmp(mode, "always") == 0)
                return true;

        if (!mode || strcmp(mode, "auto") == 0)
                return isatty(STDOUT_FILENO) ? true : false;

        errx(EXIT_FAILURE, _("invalid argument of --hyperlink: %s"), mode);
}

/*
 * Converts stat->st_mode to ls(1)-like mode string. The size of "str" must
 * be 11 bytes.
 */
char *xstrmode(mode_t mode, char *str)
{
        unsigned short i = 0;

        if (S_ISDIR(mode))
                str[i++] = 'd';
        else if (S_ISLNK(mode))
                str[i++] = 'l';
        else if (S_ISCHR(mode))
                str[i++] = 'c';
        else if (S_ISBLK(mode))
                str[i++] = 'b';
        else if (S_ISSOCK(mode))
                str[i++] = 's';
        else if (S_ISFIFO(mode))
                str[i++] = 'p';
        else if (S_ISREG(mode))
                str[i++] = '-';

        str[i++] = mode & S_IRUSR ? 'r' : '-';
        str[i++] = mode & S_IWUSR ? 'w' : '-';
        str[i++] = (mode & S_ISUID
                ? (mode & S_IXUSR ? 's' : 'S')
                : (mode & S_IXUSR ? 'x' : '-'));
        str[i++] = mode & S_IRGRP ? 'r' : '-';
        str[i++] = mode & S_IWGRP ? 'w' : '-';
        str[i++] = (mode & S_ISGID
                ? (mode & S_IXGRP ? 's' : 'S')
                : (mode & S_IXGRP ? 'x' : '-'));
        str[i++] = mode & S_IROTH ? 'r' : '-';
        str[i++] = mode & S_IWOTH ? 'w' : '-';
        str[i++] = (mode & S_ISVTX
                ? (mode & S_IXOTH ? 't' : 'T')
                : (mode & S_IXOTH ? 'x' : '-'));
        str[i] = '\0';

        return str;
}

/*
 * returns exponent (2^x=n) in range KiB..EiB (2^10..2^60)
 */
static int get_exp(uint64_t n)
{
        int shft;

        for (shft = 10; shft <= 60; shft += 10) {
                if (n < (1ULL << shft))
                        break;
        }
        return shft - 10;
}

char *size_to_human_string(int options, uint64_t bytes)
{
        char buf[32];
        int dec, exp;
        uint64_t frac;
        const char *letters = "BKMGTPE";
        char suffix[sizeof(" KiB")], *psuf = suffix;
        char c;

        if (options & SIZE_SUFFIX_SPACE)
                *psuf++ = ' ';


        exp  = get_exp(bytes);
        c    = *(letters + (exp ? exp / 10 : 0));
        dec  = exp ? bytes / (1ULL << exp) : bytes;
        frac = exp ? bytes % (1ULL << exp) : 0;

        *psuf++ = c;

        if ((options & SIZE_SUFFIX_3LETTER) && (c != 'B')) {
                *psuf++ = 'i';
                *psuf++ = 'B';
        }

        *psuf = '\0';

        /* fprintf(stderr, "exp: %d, unit: %c, dec: %d, frac: %jd\n",
         *                 exp, suffix[0], dec, frac);
         */

        /* round */
        if (frac) {
                /* get 3 digits after decimal point */
                if (frac >= UINT64_MAX / 1000)
                        frac = ((frac / 1024) * 1000) / (1ULL << (exp - 10)) ;
                else
                        frac = (frac * 1000) / (1ULL << (exp)) ;

                if (options & SIZE_DECIMAL_2DIGITS) {
                        /* round 4/5 and keep 2 digits after decimal point */
                        frac = (frac + 5) / 10 ;
                } else {
                        /* round 4/5 and keep 1 digit after decimal point */
                        frac = ((frac + 50) / 100) * 10 ;
                }

                /* rounding could have overflowed */
                if (frac == 100) {
                        dec++;
                        frac = 0;
                }
        }

        if (frac) {
                struct lconv const *l = localeconv();
                char *dp = l ? l->decimal_point : NULL;
                int len;

                if (!dp || !*dp)
                        dp = ".";

                len = snprintf(buf, sizeof(buf), "%d%s%02" PRIu64, dec, dp, frac);
                if (len > 0 && (size_t) len < sizeof(buf)) {
                        /* remove potential extraneous zero */
                        if (buf[len - 1] == '0')
                                buf[len--] = '\0';
                        /* append suffix */
                        xstrncpy(buf+len, suffix, sizeof(buf) - len);
                } else
                        *buf = '\0';    /* snprintf error */
        } else
                snprintf(buf, sizeof(buf), "%d%s", dec, suffix);

        return strdup(buf);
}

/*
 * Parses comma delimited list to array with IDs, for example:
 *
 * "aaa,bbb,ccc" --> ary[0] = FOO_AAA;
 *                   ary[1] = FOO_BBB;
 *                   ary[3] = FOO_CCC;
 *
 * The function name2id() provides conversion from string to ID.
 *
 * Returns: >= 0  : number of items added to ary[]
 *            -1  : parse error or unknown item
 *            -2  : arysz reached
 */
int string_to_idarray(const char *list, int ary[], size_t arysz,
                        int (name2id)(const char *, size_t))
{
        const char *begin = NULL, *p;
        size_t n = 0;

        if (!list || !*list || !ary || !arysz || !name2id)
                return -1;

        for (p = list; p && *p; p++) {
                const char *end = NULL;
                int id;

                if (n >= arysz)
                        return -2;
                if (!begin)
                        begin = p;              /* begin of the column name */
                if (*p == ',')
                        end = p;                /* terminate the name */
                if (*(p + 1) == '\0')
                        end = p + 1;            /* end of string */
                if (!begin || !end)
                        continue;
                if (end <= begin)
                        return -1;

                id = name2id(begin, end - begin);
                if (id == -1)
                        return -1;
                ary[ n++ ] = id;
                begin = NULL;
                if (end && !*end)
                        break;
        }
        return n;
}

/*
 * Parses the array like string_to_idarray but if format is "+aaa,bbb"
 * it adds fields to array instead of replacing them.
 */
int string_add_to_idarray(const char *list, int ary[], size_t arysz,
                        size_t *ary_pos, int (name2id)(const char *, size_t))
{
        const char *list_add;
        int r;

        if (!list || !*list || !ary_pos || *ary_pos > arysz)
                return -1;

        if (list[0] == '+')
                list_add = &list[1];
        else {
                list_add = list;
                *ary_pos = 0;
        }

        r = string_to_idarray(list_add, &ary[*ary_pos], arysz - *ary_pos, name2id);
        if (r > 0)
                *ary_pos += r;
        return r;
}

/*
 * LIST ::= <item> [, <item>]
 *
 * The <item> is translated to 'id' by name2id() function and the 'id' is used
 * as a position in the 'ary' bit array. It means that the 'id' has to be in
 * range <0..N> where N < sizeof(ary) * NBBY.
 *
 * If allow_range is enabled:
 * An item ending in '+' also sets all bits in <0..N>.
 * An item beginning with '+' also sets all bits in <N..allow_minus>.
 *
 * Returns: 0 on success, <0 on error.
 */
int string_to_bitarray(const char *list,
                     char *ary,
                     int (*name2bit)(const char *, size_t),
                     size_t allow_range)
{
        const char *begin = NULL, *p;

        if (!list || !name2bit || !ary)
                return -EINVAL;

        for (p = list; p && *p; p++) {
                const char *end = NULL;
                int bit, set_lower = 0, set_higher = 0;

                if (!begin)
                        begin = p;              /* begin of the level name */
                if (*p == ',')
                        end = p;                /* terminate the name */
                if (*(p + 1) == '\0')
                        end = p + 1;            /* end of string */
                if (!begin || !end)
                        continue;
                if (end <= begin)
                        return -1;
                if (allow_range) {
                        if (*(end - 1) == '+') {
                                end--;
                                set_lower = 1;
                        } else if (*begin == '+') {
                                begin++;
                                set_higher = 1;
                        }
                }

                bit = name2bit(begin, end - begin);
                if (bit < 0)
                        return bit;
                setbit(ary, bit);
                if (set_lower)
                        while (--bit >= 0)
                                setbit(ary, bit);
                else if (set_higher)
                        while (++bit < (int) allow_range)
                                setbit(ary, bit);
                begin = NULL;
                if (end && !*end)
                        break;
        }
        return 0;
}

/*
 * LIST ::= <item> [, <item>]
 *
 * The <item> is translated to 'id' by name2flag() function and the flags is
 * set to the 'mask'
*
 * Returns: 0 on success, <0 on error.
 */
int string_to_bitmask(const char *list,
                     unsigned long *mask,
                     long (*name2flag)(const char *, size_t))
{
        const char *begin = NULL, *p;

        if (!list || !name2flag || !mask)
                return -EINVAL;

        for (p = list; p && *p; p++) {
                const char *end = NULL;
                long flag;

                if (!begin)
                        begin = p;              /* begin of the level name */
                if (*p == ',')
                        end = p;                /* terminate the name */
                if (*(p + 1) == '\0')
                        end = p + 1;            /* end of string */
                if (!begin || !end)
                        continue;
                if (end <= begin)
                        return -1;

                flag = name2flag(begin, end - begin);
                if (flag < 0)
                        return flag;    /* error */
                *mask |= flag;
                begin = NULL;
                if (end && !*end)
                        break;
        }
        return 0;
}

/*
 * Parse the lower and higher values in a string containing
 * "lower:higher" or "lower-higher" format. Note that either
 * the lower or the higher values may be missing, and the def
 * value will be assigned to it by default.
 *
 * Returns: 0 on success, <0 on error.
 */
int ul_parse_range(const char *str, int *lower, int *upper, int def)
{
        char *end = NULL;

        if (!str)
                return 0;

        *upper = *lower = def;
        errno = 0;

        if (*str == ':') {                              /* <:N> */
                str++;
                *upper = strtol(str, &end, 10);
                if (errno || !end || *end || end == str)
                        return -1;
        } else {
                *upper = *lower = strtol(str, &end, 10);
                if (errno || !end || end == str)
                        return -1;

                if (*end == ':' && !*(end + 1))         /* <M:> */
                        *upper = def;
                else if (*end == '-' || *end == ':') {  /* <M:N> <M-N> */
                        str = end + 1;
                        end = NULL;
                        errno = 0;
                        *upper = strtol(str, &end, 10);

                        if (errno || !end || *end || end == str)
                                return -1;
                }
        }
        return 0;
}

static const char *next_path_segment(const char *str, size_t *sz)
{
        const char *start, *p;

        start = str;
        *sz = 0;
        while (start && *start == '/' && *(start + 1) == '/')
                start++;

        if (!start || !*start)
                return NULL;

        for (*sz = 1, p = start + 1; *p && *p != '/'; p++) {
                (*sz)++;
        }

        return start;
}

int streq_paths(const char *a, const char *b)
{
        while (a && b) {
                size_t a_sz, b_sz;
                const char *a_seg = next_path_segment(a, &a_sz);
                const char *b_seg = next_path_segment(b, &b_sz);

                /*
                fprintf(stderr, "A>>>(%zu) '%s'\n", a_sz, a_seg);
                fprintf(stderr, "B>>>(%zu) '%s'\n", b_sz, b_seg);
                */

                /* end of the path */
                if (a_sz + b_sz == 0)
                        return 1;

                /* ignore trailing slash */
                if (a_sz + b_sz == 1 &&
                    ((a_seg && *a_seg == '/') || (b_seg && *b_seg == '/')))
                        return 1;

                if (!a_seg || !b_seg)
                        break;
                if (a_sz != b_sz || strncmp(a_seg, b_seg, a_sz) != 0)
                        break;

                a = a_seg + a_sz;
                b = b_seg + b_sz;
        };

        return 0;
}

/* concatenate two strings to a new string, the size of the second string is limited by @b */
char *ul_strnconcat(const char *s, const char *suffix, size_t b)
{
        size_t a;
        char *r;

        if (!s && !suffix)
                return strdup("");
        if (!s)
                return strndup(suffix, b);
        if (!suffix)
                return strdup(s);

        assert(s);
        assert(suffix);

        a = strlen(s);
        if (b > ((size_t) -1) - a)
                return NULL;

        r = malloc(a + b + 1);
        if (!r)
                return NULL;

        memcpy(r, s, a);
        memcpy(r + a, suffix, b);
        r[a+b] = 0;

        return r;
}

/* concatenate two strings to a new string */
char *ul_strconcat(const char *s, const char *suffix)
{
        return ul_strnconcat(s, suffix, suffix ? strlen(suffix) : 0);
}

/* concatenate @s and string defined by @format to a new string */
char *ul_strfconcat(const char *s, const char *format, ...)
{
        va_list ap;
        char *val, *res;
        int sz;

        va_start(ap, format);
        sz = vasprintf(&val, format, ap);
        va_end(ap);

        if (sz < 0)
                return NULL;

        res = ul_strnconcat(s, val, sz);
        free(val);
        return res;
}

int ul_strappend(char **a, const char *b)
{
        size_t al, bl;
        char *tmp;

        if (!a)
                return -EINVAL;
        if (!b || !*b)
                return 0;
        if (!*a) {
                *a = strdup(b);
                return !*a ? -ENOMEM : 0;
        }

        al = strlen(*a);
        bl = strlen(b);

        tmp = realloc(*a, al + bl + 1);
        if (!tmp)
                return -ENOMEM;
        *a = tmp;
        memcpy((*a) + al, b, bl + 1);
        return 0;
}

/* the hybrid version of strfconcat and strappend. */
int strfappend(char **a, const char *format, ...)
{
        va_list ap;
        int res;

        va_start(ap, format);
        res = ul_strvfappend(a, format, ap);
        va_end(ap);

        return res;
}

extern int ul_strvfappend(char **a, const char *format, va_list ap)
{
        char *val;
        int sz;
        int res;

        sz = vasprintf(&val, format, ap);
        if (sz < 0)
                return -errno;

        res = ul_strappend(a, val);
        free(val);
        return res;
}

static size_t strcspn_escaped(const char *s, const char *reject)
{
        int escaped = 0;
        int n;

        for (n=0; s[n]; n++) {
                if (escaped)
                        escaped = 0;
                else if (s[n] == '\\')
                        escaped = 1;
                else if (strchr(reject, s[n]))
                        break;
        }

        /* if s ends in \, return index of previous char */
        return n - escaped;
}

/*
 * Like strchr() but ignores @c if escaped by '\', '\\' is interpreted like '\'.
 *
 * For example for @c='X':
 *
 *      "abcdXefgXh"    --> "XefgXh"
 *      "abcd\XefgXh"   --> "Xh"
 *      "abcd\\XefgXh"  --> "XefgXh"
 *      "abcd\\\XefgXh" --> "Xh"
 *      "abcd\Xefg\Xh"  --> (null)
 *
 *      "abcd\\XefgXh"  --> "\XefgXh"   for @c='\\'
 */
char *ul_strchr_escaped(const char *s, int c)
{
        char *p;
        int esc = 0;

        for (p = (char *) s; p && *p; p++) {
                if (!esc && *p == '\\') {
                        esc = 1;
                        continue;
                }
                if (*p == c && (!esc || c == '\\'))
                        return p;
                esc = 0;
        }

        return NULL;
}

/* Split a string into words. */
const char *ul_split(const char **state, size_t *l, const char *separator, int quoted)
{
        const char *current;

        current = *state;

        if (!*current) {
                assert(**state == '\0');
                return NULL;
        }

        current += strspn(current, separator);
        if (!*current) {
                *state = current;
                return NULL;
        }

        if (quoted && strchr("\'\"", *current)) {
                char quotechars[2] = {*current, '\0'};

                *l = strcspn_escaped(current + 1, quotechars);
                if (current[*l + 1] == '\0' || current[*l + 1] != quotechars[0] ||
                    (current[*l + 2] && !strchr(separator, current[*l + 2]))) {
                        /* right quote missing or garbage at the end */
                        *state = current;
                        return NULL;
                }
                *state = current++ + *l + 2;
        } else if (quoted) {
                *l = strcspn_escaped(current, separator);
                if (current[*l] && !strchr(separator, current[*l])) {
                        /* unfinished escape */
                        *state = current;
                        return NULL;
                }
                *state = current + *l;
        } else {
                *l = strcspn(current, separator);
                *state = current + *l;
        }

        return current;
}

/* Rewind file pointer forward to new line.  */
int skip_fline(FILE *fp)
{
        int ch;

        do {
                if ((ch = fgetc(fp)) == EOF)
                        return 1;
                if (ch == '\n')
                        return 0;
        } while (1);
}


/* compare two strings, but ignoring non-alnum and case of the characters, for example
 * "Hello (123)!" is the same as "hello123".
 */
int ul_stralnumcmp(const char *p1, const char *p2)
{
        const unsigned char *s1 = (const unsigned char *) p1;
        const unsigned char *s2 = (const unsigned char *) p2;
        unsigned char c1, c2;

        do {
                do {
                        c1 = (unsigned char) *s1++;
                } while (c1 != '\0' && !isalnum((unsigned int) c1));

                do {
                        c2 = (unsigned char) *s2++;
                } while (c2 != '\0' && !isalnum((unsigned int) c2));

                if (c1 != '\0')
                        c1 = tolower(c1);
                if (c2 != '\0')
                        c2 = tolower(c2);
                if (c1 == '\0')
                        return c1 - c2;
        } while (c1 == c2);

        return c1 - c2;
}

/*
 * Parses the first option from @optstr. The @optstr pointer is set to the beginning
 * of the next option. The options string looks like 'aaa,bbb=data,foo,bar="xxx"'.
 *
 * Note this function is used by libmount to parse mount options. Be careful when modify.
 *
 * Returns -EINVAL on parse error, 1 at the end of optstr and 0 on success.
 */
int ul_optstr_next(char **optstr, char **name, size_t *namesz,
                   char **value, size_t *valsz)
{
        int open_quote = 0;
        char *start = NULL, *stop = NULL, *p, *sep = NULL;
        char *optstr0;

        assert(optstr);
        assert(*optstr);

        optstr0 = *optstr;

        if (name)
                *name = NULL;
        if (namesz)
                *namesz = 0;
        if (value)
                *value = NULL;
        if (valsz)
                *valsz = 0;

        /* trim leading commas as to not invalidate option
         * strings with multiple consecutive commas */
        while (optstr0 && *optstr0 == ',')
                optstr0++;

        for (p = optstr0; p && *p; p++) {
                if (!start && *p == '=')
                        return -EINVAL;
                if (!start)
                        start = p;              /* beginning of the option item */
                if (*p == '"' && (p == optstr0 || *(p - 1) != '\\'))
                        open_quote ^= 1;        /* reverse the status */
                if (open_quote)
                        continue;               /* still in quoted block */
                if (!sep && p > start && *p == '=')
                        sep = p;                /* name and value separator */
                if (*p == ',' && (p == optstr0 || *(p - 1) != '\\'))
                        stop = p;               /* terminate the option item */
                else if (*(p + 1) == '\0')
                        stop = p + 1;           /* end of optstr */
                if (!start || !stop)
                        continue;
                if (stop <= start)
                        return -EINVAL;

                if (name)
                        *name = start;
                if (namesz)
                        *namesz = sep ? sep - start : stop - start;
                *optstr = *stop ? stop + 1 : stop;

                if (sep) {
                        if (value)
                                *value = sep + 1;
                        if (valsz)
                                *valsz = stop - sep - 1;
                }
                return 0;
        }

        return 1;                               /* end of optstr */
}

int ul_optstr_is_valid(const char *optstr)
{
        int rc;
        char *p = (char *) optstr;

        while ((rc = ul_optstr_next(&p, NULL, NULL, NULL, NULL)) == 0);
        return rc < 0 ? 0 : 1;
}

#ifdef TEST_PROGRAM_STRUTILS

#include "cctype.h"

struct testS {
        char *name;
        char *value;
};

static int test_strdup_to_member(int argc, char *argv[])
{
        struct testS *xx;

        if (argc < 3)
                return EXIT_FAILURE;

        xx = calloc(1, sizeof(*xx));
        if (!xx)
                err(EXIT_FAILURE, "calloc() failed");

        strdup_to_struct_member(xx, name, argv[1]);
        strdup_to_struct_member(xx, value, argv[2]);

        if (strcmp(xx->name, argv[1]) != 0 &&
            strcmp(xx->value, argv[2]) != 0)
                errx(EXIT_FAILURE, "strdup_to_struct_member() failed");

        printf("1: '%s', 2: '%s'\n", xx->name, xx->value);

        free(xx->name);
        free(xx->value);
        free(xx);
        return EXIT_SUCCESS;
}

static int test_strutils_sizes(int argc, char *argv[])
{
        uintmax_t size = 0;
        char *hum1, *hum2, *hum3;

        if (argc < 2)
                return EXIT_FAILURE;

        if (strtosize(argv[1], &size))
                errx(EXIT_FAILURE, "invalid size '%s' value", argv[1]);

        hum1 = size_to_human_string(SIZE_SUFFIX_1LETTER, size);
        hum2 = size_to_human_string(SIZE_SUFFIX_3LETTER |
                                    SIZE_SUFFIX_SPACE, size);
        hum3 = size_to_human_string(SIZE_SUFFIX_3LETTER |
                                    SIZE_SUFFIX_SPACE |
                                    SIZE_DECIMAL_2DIGITS, size);

        printf("%25s : %20ju : %8s : %12s : %13s\n", argv[1], size, hum1, hum2, hum3);
        free(hum1);
        free(hum2);
        free(hum3);

        return EXIT_SUCCESS;
}

static int test_strutils_cmp_paths(int argc, char *argv[])
{
        int rc = streq_paths(argv[1], argv[2]);

        if (argc < 3)
                return EXIT_FAILURE;

        printf("%s: '%s' '%s'\n", rc == 1 ? "YES" : "NOT", argv[1], argv[2]);
        return EXIT_SUCCESS;
}

static int test_strutils_normalize(int argc, char *argv[])
{
        unsigned char *src, *dst, *org;
        size_t sz, len;

        if (argc < 2)
                return EXIT_FAILURE;

        org = (unsigned char *) strdup(argv[1]);
        src = (unsigned char *) strdup((char *) org);
        len = strlen((char *) src);
        dst = malloc(len + 1);

        if (!org || !src || !dst)
                goto done;

        /* two buffers */
        sz = __normalize_whitespace(src, len, dst, len + 1);
        printf("1: '%s' --> '%s' [sz=%zu]\n", src, dst, sz);

        /* one buffer */
        sz = normalize_whitespace(src);
        printf("2: '%s' --> '%s' [sz=%zu]\n", org, src, sz);

done:
        free(src);
        free(dst);
        free(org);

        return EXIT_SUCCESS;
}

static int test_strutils_cstrcasecmp(int argc, char *argv[])
{
        char *a, *b;

        if (argc < 3)
                return EXIT_FAILURE;

        a = argv[1];
        b = argv[2];

        if (!a || !b)
                return EXIT_FAILURE;

        printf("cmp    '%s' '%s' = %d\n", a, b, strcasecmp(a, b));
        printf("c_cmp  '%s' '%s' = %d\n", a, b, c_strcasecmp(a, b));
        printf("c_ncmp '%s' '%s' = %d\n", a, b, c_strncasecmp(a, b, strlen(a)));

        return EXIT_SUCCESS;
}

int main(int argc, char *argv[])
{
        if (argc == 3 && strcmp(argv[1], "--size") == 0) {
                return test_strutils_sizes(argc - 1, argv + 1);

        } else if (argc == 3 && strcmp(argv[1], "--parse-switch") == 0) {
                printf("'%s'-->%d\n", argv[2], ul_parse_switch(argv[2],
                                                "on", "off",
                                                "enable", "disable",
                                                "yes", "no",
                                                "1", "0",
                                                NULL));
                return EXIT_SUCCESS;
        } else if (argc == 4 && strcmp(argv[1], "--cmp-paths") == 0) {
                return test_strutils_cmp_paths(argc - 1, argv + 1);

        } else if (argc == 4 && strcmp(argv[1], "--strdup-member") == 0) {
                return test_strdup_to_member(argc - 1, argv + 1);

        } else if  (argc == 4 && strcmp(argv[1], "--stralnumcmp") == 0) {
                printf("%s\n", ul_stralnumcmp(argv[2], argv[3]) == 0 ?
                                "match" : "dismatch");
                return EXIT_SUCCESS;

        } else if (argc == 4 && strcmp(argv[1], "--cstrcasecmp") == 0) {
                return test_strutils_cstrcasecmp(argc - 1, argv + 1);

        } else if (argc == 3 && strcmp(argv[1], "--normalize") == 0) {
                return test_strutils_normalize(argc - 1, argv + 1);

        } else if (argc == 3 && strcmp(argv[1], "--strtos64") == 0) {
                printf("'%s'-->%jd\n", argv[2], strtos64_or_err(argv[2], "strtos64 failed"));
                return EXIT_SUCCESS;
        } else if (argc == 3 && strcmp(argv[1], "--strtou64") == 0) {
                printf("'%s'-->%ju\n", argv[2], strtou64_or_err(argv[2], "strtou64 failed"));
                return EXIT_SUCCESS;
        } else if (argc == 3 && strcmp(argv[1], "--strtos32") == 0) {
                printf("'%s'-->%d\n", argv[2], strtos32_or_err(argv[2], "strtos32 failed"));
                return EXIT_SUCCESS;
        } else if (argc == 3 && strcmp(argv[1], "--strtou32") == 0) {
                printf("'%s'-->%u\n", argv[2], strtou32_or_err(argv[2], "strtou32 failed"));
                return EXIT_SUCCESS;
        } else if (argc == 3 && strcmp(argv[1], "--strtos16") == 0) {
                printf("'%s'-->%hd\n", argv[2], strtos16_or_err(argv[2], "strtos16 failed"));
                return EXIT_SUCCESS;
        } else if (argc == 3 && strcmp(argv[1], "--strtou16") == 0) {
                printf("'%s'-->%hu\n", argv[2], strtou16_or_err(argv[2], "strtou16 failed"));
                return EXIT_SUCCESS;

        } else if (argc == 4 && strcmp(argv[1], "--strchr-escaped") == 0) {
                printf("\"%s\" --> \"%s\"\n", argv[2], ul_strchr_escaped(argv[2], *argv[3]));
                return EXIT_SUCCESS;

        } else if (argc == 2 && strcmp(argv[1], "--next-string") == 0) {
                char *buf = "abc\0Y\0\0xyz\0X";
                char *end = buf + 12;
                char *p = buf;

                do {
                        printf("str: '%s'\n", p);
                } while ((p = ul_next_string(p, end)));

                return EXIT_SUCCESS;

        } else if (argc == 3 && strcmp(argv[1], "--optstr") == 0) {

                size_t namesz, valsz;
                char *name = NULL, *val = NULL;
                char *p = argv[2];
                int rc;

                if (!ul_optstr_is_valid(p))
                        errx(EXIT_FAILURE, _("unsupported option format: %s"), p);

                while ((rc = ul_optstr_next(&p, &name, &namesz, &val, &valsz)) == 0) {
                        printf("'%.*s' : '%.*s'\n", (int) namesz, name,
                                                   (int) valsz, val);
                }
                if (rc == 1)
                        return EXIT_SUCCESS;
        } else {
                fprintf(stderr, "usage: %1$s --size <number>[suffix]\n"
                                "       %1$s --parse-switch <str>\n"
                                "       %1$s --cmp-paths <path> <path>\n"
                                "       %1$s --strdup-member <str> <str>\n"
                                "       %1$s --stralnumcmp <str> <str>\n"
                                "       %1$s --cstrcasecmp <str> <str>\n"
                                "       %1$s --normalize <str>\n"
                                "       %1$s --strto{s,u}{16,32,64} <str>\n"
                                "       %1$s --optstr <str>\n",
                                argv[0]);
                exit(EXIT_FAILURE);
        }

        return EXIT_FAILURE;
}
#endif /* TEST_PROGRAM_STRUTILS */