src/lib/strnum.c

/* Copyright (c) 2010-2018 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "strnum.h"

bool str_is_numeric(const char *str, char end_char)
{
    if (*str == '\0' || *str == end_char)
        return FALSE;

    while (*str != '\0' && *str != end_char) {
        if (*str < '0' || *str > '9')
            return FALSE;
        str++;
    }

    return TRUE;
}

bool str_is_float(const char *str, char end_char)
{
    bool dot_seen = FALSE;
    bool num_seen = FALSE;

    if (*str == '\0' || *str == end_char)
        return FALSE;

    while (*str != '\0' && *str != end_char) {
        if (*str == '.') {
            if (dot_seen || !num_seen) return FALSE;
            dot_seen = TRUE;
            num_seen = FALSE;
            str++;
            /* enforce that number follows dot */
            continue;
        }
        if (*str < '0' || *str > '9')
            return FALSE;
        num_seen = TRUE;
        str++;
    }

    return num_seen;
}

/*
 * Unsigned decimal
 */

#define STR_PARSE_U__TEMPLATE(name, type)                     \
int name(const char *str, type *num_r, const char **endp_r)   \
{                                                             \
    uintmax_t l;                                                \
    if (str_parse_uintmax(str, &l, endp_r) < 0 || l > (type)-1) \
        return -1;                                                \
    *num_r = (type)l;                                           \
    return 0;                                                   \
}

STR_PARSE_U__TEMPLATE(str_parse_uint, unsigned int)
STR_PARSE_U__TEMPLATE(str_parse_ulong, unsigned long)
STR_PARSE_U__TEMPLATE(str_parse_ullong, unsigned long long)
STR_PARSE_U__TEMPLATE(str_parse_uint32, uint32_t)
STR_PARSE_U__TEMPLATE(str_parse_uint64, uint64_t)

#define STR_TO_U__TEMPLATE(name, type)                        \
int name(const char *str, type *num_r)                        \
{                                                             \
    uintmax_t l;                                                \
    if (str_to_uintmax(str, &l) < 0 || l > (type)-1)            \
        return -1;                                                \
    *num_r = (type)l;                                           \
    return 0;                                                   \
}

STR_TO_U__TEMPLATE(str_to_uint, unsigned int)
STR_TO_U__TEMPLATE(str_to_ulong, unsigned long)
STR_TO_U__TEMPLATE(str_to_ullong, unsigned long long)
STR_TO_U__TEMPLATE(str_to_uint32, uint32_t)
STR_TO_U__TEMPLATE(str_to_uint64, uint64_t)

int str_parse_uintmax(const char *str, uintmax_t *num_r,
    const char **endp_r)
{
    uintmax_t n = 0;

    if (*str < '0' || *str > '9')
        return -1;

    do {
        if (n >= ((uintmax_t)-1 / 10)) {
            if (n > (uintmax_t)-1 / 10)
                return -1;
            if ((uintmax_t)(*str - '0') > ((uintmax_t)-1 % 10))
                return -1;
        }
        n = n * 10 + (*str - '0');
        str++;
    } while (*str >= '0' && *str <= '9');

    if (endp_r != NULL)
        *endp_r = str;
    *num_r = n;
    return 0;
}
int str_to_uintmax(const char *str, uintmax_t *num_r)
{
    const char *endp;
    uintmax_t n;
    int ret = str_parse_uintmax(str, &n, &endp);
    if ((ret != 0) || (*endp != '\0'))
        return -1;
    *num_r = n;
    return 0;
}

bool str_uint_equals(const char *str, uintmax_t num)
{
    uintmax_t l;

    if (str_to_uintmax(str, &l) < 0)
        return FALSE;
    return l == num;
}

/*
 * Unsigned hexadecimal
 */

#define STR_PARSE_UHEX__TEMPLATE(name, type)                       \
int name(const char *str, type *num_r, const char **endp_r)        \
{                                                                  \
    uintmax_t l;                                                     \
    if (str_parse_uintmax_hex(str, &l, endp_r) < 0 || l > (type)-1)  \
        return -1;                                                     \
    *num_r = (type)l;                                                \
    return 0;                                                        \
}

STR_PARSE_UHEX__TEMPLATE(str_parse_uint_hex, unsigned int)
STR_PARSE_UHEX__TEMPLATE(str_parse_ulong_hex, unsigned long)
STR_PARSE_UHEX__TEMPLATE(str_parse_ullong_hex, unsigned long long)
STR_PARSE_UHEX__TEMPLATE(str_parse_uint32_hex, uint32_t)
STR_PARSE_UHEX__TEMPLATE(str_parse_uint64_hex, uint64_t)

#define STR_TO_UHEX__TEMPLATE(name, type)                          \
int name(const char *str, type *num_r)                             \
{                                                                  \
    uintmax_t l;                                                     \
    if (str_to_uintmax_hex(str, &l) < 0 || l > (type)-1)             \
        return -1;                                                     \
    *num_r = (type)l;                                                \
    return 0;                                                        \
}

STR_TO_UHEX__TEMPLATE(str_to_uint_hex, unsigned int)
STR_TO_UHEX__TEMPLATE(str_to_ulong_hex, unsigned long)
STR_TO_UHEX__TEMPLATE(str_to_ullong_hex, unsigned long long)
STR_TO_UHEX__TEMPLATE(str_to_uint32_hex, uint32_t)
STR_TO_UHEX__TEMPLATE(str_to_uint64_hex, uint64_t)

static inline int _str_parse_hex(const char ch,
    unsigned int *hex_r)
{
    switch (ch) {
    case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
        *hex_r = (unsigned int)(ch - 'a' + 10);
        return 0;
    case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
        *hex_r = (unsigned int)(ch - 'A' + 10);
        return 0;
    case '0': case '1': case '2': case '3': case '4':
    case '5': case '6': case '7': case '8': case '9':
        *hex_r = (unsigned int)(ch - '0');
        return 0;
    default:
        break;
    }
    return -1;
}
int str_parse_uintmax_hex(const char *str, uintmax_t *num_r,
    const char **endp_r)
{
    unsigned int hex;
    uintmax_t n = 0;

    if (_str_parse_hex(*str, &hex) < 0)
        return -1;

    do {
        if (n > (uintmax_t)-1 >> 4)
            return -1;
        n = (n << 4) + hex;
        str++;
    } while (_str_parse_hex(*str, &hex) >= 0);
    if (endp_r != NULL)
        *endp_r = str;
    *num_r = n;
    return 0;
}
int str_to_uintmax_hex(const char *str, uintmax_t *num_r)
{
    const char *endp;
    uintmax_t n;
    int ret = str_parse_uintmax_hex(str, &n, &endp);
    if ((ret != 0) || (*endp != '\0'))
        return -1;
    *num_r = n;
    return 0;
}

/*
 * Unsigned octal
 */

#define STR_PARSE_UOCT__TEMPLATE(name, type)                       \
int name(const char *str, type *num_r, const char **endp_r)        \
{                                                                  \
    uintmax_t l;                                                     \
    if (str_parse_uintmax_oct(str, &l, endp_r) < 0 || l > (type)-1)  \
        return -1;                                                     \
    *num_r = (type)l;                                                \
    return 0;                                                        \
}

STR_PARSE_UOCT__TEMPLATE(str_parse_uint_oct, unsigned int)
STR_PARSE_UOCT__TEMPLATE(str_parse_ulong_oct, unsigned long)
STR_PARSE_UOCT__TEMPLATE(str_parse_ullong_oct, unsigned long long)
STR_PARSE_UOCT__TEMPLATE(str_parse_uint32_oct, uint32_t)
STR_PARSE_UOCT__TEMPLATE(str_parse_uint64_oct, uint64_t)

#define STR_TO_UOCT__TEMPLATE(name, type)                          \
int name(const char *str, type *num_r)                             \
{                                                                  \
    uintmax_t l;                                                     \
    if (str_to_uintmax_oct(str, &l) < 0 || l > (type)-1)             \
        return -1;                                                     \
    *num_r = (type)l;                                                \
    return 0;                                                        \
}

STR_TO_UOCT__TEMPLATE(str_to_uint_oct, unsigned int)
STR_TO_UOCT__TEMPLATE(str_to_ulong_oct, unsigned long)
STR_TO_UOCT__TEMPLATE(str_to_ullong_oct, unsigned long long)
STR_TO_UOCT__TEMPLATE(str_to_uint32_oct, uint32_t)
STR_TO_UOCT__TEMPLATE(str_to_uint64_oct, uint64_t)

int str_parse_uintmax_oct(const char *str, uintmax_t *num_r,
    const char **endp_r)
{
    uintmax_t n = 0;

    if (*str < '0' || *str > '7')
        return -1;

    for (; *str >= '0' && *str <= '7'; str++) {
        if (n > (uintmax_t)-1 >> 3)
            return -1;
        n = (n << 3) + (*str - '0');
    }
    if (endp_r != NULL)
        *endp_r = str;
    *num_r = n;
    return 0;
}
int str_to_uintmax_oct(const char *str, uintmax_t *num_r)
{
    const char *endp;
    uintmax_t n;
    int ret = str_parse_uintmax_oct(str, &n, &endp);
    if ((ret != 0) || (*endp != '\0'))
        return -1;
    *num_r = n;
    return 0;
}

/*
 * Signed
 */

#define STR_PARSE_S__TEMPLATE(name, type, int_min, int_max)   \
int name(const char *str, type *num_r, const char **endp_r)   \
{                                                             \
    intmax_t l;                                                 \
    if (str_parse_intmax(str, &l, endp_r) < 0)                  \
        return -1;                                                \
    if (l < int_min || l > int_max)                             \
        return -1;                                                \
    *num_r = (type)l;                                           \
    return 0;                                                   \
}

STR_PARSE_S__TEMPLATE(str_parse_int, int, INT_MIN, INT_MAX)
STR_PARSE_S__TEMPLATE(str_parse_long, long, LONG_MIN, LONG_MAX)
STR_PARSE_S__TEMPLATE(str_parse_llong, long long, LLONG_MIN, LLONG_MAX)
STR_PARSE_S__TEMPLATE(str_parse_int32, int32_t, INT32_MIN, INT32_MAX)
STR_PARSE_S__TEMPLATE(str_parse_int64, int64_t, INT64_MIN, INT64_MAX)

#define STR_TO_S__TEMPLATE(name, type, int_min, int_max)      \
int name(const char *str, type *num_r)                        \
{                                                             \
    intmax_t l;                                                 \
    if (str_to_intmax(str, &l) < 0)                             \
        return -1;                                                \
    if (l < int_min || l > int_max)                             \
        return -1;                                                \
    *num_r = (type)l;                                           \
    return 0;                                                   \
}

STR_TO_S__TEMPLATE(str_to_int, int, INT_MIN, INT_MAX)
STR_TO_S__TEMPLATE(str_to_long, long, LONG_MIN, LONG_MAX)
STR_TO_S__TEMPLATE(str_to_llong, long long, LLONG_MIN, LLONG_MAX)
STR_TO_S__TEMPLATE(str_to_int32, int32_t, INT32_MIN, INT32_MAX)
STR_TO_S__TEMPLATE(str_to_int64, int64_t, INT64_MIN, INT64_MAX)

int str_parse_intmax(const char *str, intmax_t *num_r,
    const char **endp_r)
{
    bool neg = FALSE;
    uintmax_t l;

    if (*str == '-') {
        neg = TRUE;
        str++;
    }
    if (str_parse_uintmax(str, &l, endp_r) < 0)
        return -1;

    if (!neg) {
        if (l > INTMAX_MAX)
            return -1;
        *num_r = (intmax_t)l;
    } else {
        if (l > UINTMAX_MAX - (UINTMAX_MAX + INTMAX_MIN))
            return -1;
        *num_r = (intmax_t)-l;
    }
    return 0;
}
int str_to_intmax(const char *str, intmax_t *num_r)
{
    const char *endp;
    intmax_t n;
    int ret = str_parse_intmax(str, &n, &endp);
    if ((ret != 0) || (*endp != '\0'))
        return -1;
    *num_r = n;
    return 0;
}

/*
 * Special numeric types
 */

static int verify_xid(uintmax_t l, unsigned int result_size)
{
    unsigned int result_bits;

    /* we assume that result is a signed type,
       but that it can never be negative */
    result_bits = result_size*CHAR_BIT - 1;
    if ((l >> result_bits) != 0)
        return -1;
    return 0;
}

int str_to_uid(const char *str, uid_t *num_r)
{
    uintmax_t l;

    if (str_to_uintmax(str, &l) < 0)
        return -1;

    if (verify_xid(l, sizeof(*num_r)) < 0)
        return -1;
    *num_r = (uid_t)l;
    return 0;
}

int str_to_gid(const char *str, gid_t *num_r)
{
    uintmax_t l;

    if (str_to_uintmax(str, &l) < 0)
        return -1;

    /* OS X uses negative GIDs */
#ifndef __APPLE__
    if (verify_xid(l, sizeof(*num_r)) < 0)
        return -1;
#endif
    *num_r = (gid_t)l;
    return 0;
}

int str_to_pid(const char *str, pid_t *num_r)
{
    uintmax_t l;

    if (str_to_uintmax(str, &l) < 0)
        return -1;

    if (verify_xid(l, sizeof(*num_r)) < 0)
        return -1;
    *num_r = (pid_t)l;
    return 0;
}

int str_to_ino(const char *str, ino_t *num_r)
{
    uintmax_t l;

    if (str_to_uintmax(str, &l) < 0)
        return -1;

    if (verify_xid(l, sizeof(*num_r)) < 0)
        return -1;
    *num_r = (ino_t)l;
    return 0;
}

int str_to_uoff(const char *str, uoff_t *num_r)
{
    uintmax_t l;

    if (str_to_uintmax(str, &l) < 0)
        return -1;

    if (l > (uoff_t)-1)
        return -1;
    *num_r = (uoff_t)l;
    return 0;
}

int str_to_time(const char *str, time_t *num_r)
{
    intmax_t l;

    if (str_to_intmax(str, &l) < 0)
        return -1;

    *num_r = (time_t)l;
    return 0;
}

STR_PARSE_U__TEMPLATE(str_parse_uoff, uoff_t)

/*
 * Error handling
 */

const char *str_num_error(const char *str)
{
    if (*str == '-') {
        if (!str_is_numeric(str + 1, '\0'))
            return "Not a valid number";
        return "Number too small";
    } else {
        if (!str_is_numeric(str, '\0'))
            return "Not a valid number";
        return "Number too large";
    }
}