source: MondoRescue/branches/3.3/mindi-busybox/libbb/compare_string_array.c@ 3901

/* vi: set sw=4 ts=4: */
/*
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */

#include "libbb.h"

/*
 * Return NULL if string is not prefixed with key. Return pointer to the
 * first character in string after the prefix key. If key is an empty string,
 * return pointer to the beginning of string.
 */
char* FAST_FUNC is_prefixed_with(const char *string, const char *key)
{
#if 0   /* Two passes over key - probably slower */
    int len = strlen(key);
    if (strncmp(string, key, len) == 0)
        return string + len;
    return NULL;
#else   /* Open-coded */
    while (*key != '\0') {
        if (*key != *string)
            return NULL;
        key++;
        string++;
    }
    return (char*)string;
#endif
}

/*
 * Return NULL if string is not suffixed with key. Return pointer to the
 * beginning of prefix key in string. If key is an empty string return pointer
 * to the end of string.
 */
char* FAST_FUNC is_suffixed_with(const char *string, const char *key)
{
    size_t key_len = strlen(key);
    ssize_t len_diff = strlen(string) - key_len;

    if (len_diff >= 0) {
        string += len_diff;
        if (strcmp(string, key) == 0) {
            return (char*)string;
        }
    }

    return NULL;
}

/* returns the array index of the string */
/* (index of first match is returned, or -1) */
int FAST_FUNC index_in_str_array(const char *const string_array[], const char *key)
{
    int i;

    for (i = 0; string_array[i] != 0; i++) {
        if (strcmp(string_array[i], key) == 0) {
            return i;
        }
    }
    return -1;
}

int FAST_FUNC index_in_strings(const char *strings, const char *key)
{
    int idx = 0;

    while (*strings) {
        if (strcmp(strings, key) == 0) {
            return idx;
        }
        strings += strlen(strings) + 1; /* skip NUL */
        idx++;
    }
    return -1;
}

/* returns the array index of the string, even if it matches only a beginning */
/* (index of first match is returned, or -1) */
#ifdef UNUSED
int FAST_FUNC index_in_substr_array(const char *const string_array[], const char *key)
{
    int i;
    if (key[0]) {
        for (i = 0; string_array[i] != 0; i++) {
            if (is_prefixed_with(string_array[i], key)) {
                return i;
            }
        }
    }
    return -1;
}
#endif

int FAST_FUNC index_in_substrings(const char *strings, const char *key)
{
    int matched_idx = -1;
    const int len = strlen(key);

    if (len) {
        int idx = 0;
        while (*strings) {
            if (strncmp(strings, key, len) == 0) {
                if (strings[len] == '\0')
                    return idx; /* exact match */
                if (matched_idx >= 0)
                    return -1; /* ambiguous match */
                matched_idx = idx;
            }
            strings += strlen(strings) + 1; /* skip NUL */
            idx++;
        }
    }
    return matched_idx;
}

const char* FAST_FUNC nth_string(const char *strings, int n)
{
    while (n) {
        n--;
        strings += strlen(strings) + 1;
    }
    return strings;
}

#ifdef UNUSED_SO_FAR /* only brctl.c needs it yet */
/* Returns 0 for no, 1 for yes or a negative value on error.  */
smallint FAST_FUNC yesno(const char *str)
{
    static const char no_yes[] ALIGN1 =
        "0\0" "off\0" "no\0"
        "1\0" "on\0" "yes\0";
    int ret = index_in_substrings(no_yes, str);
    return ret / 3;
}
#endif

#if ENABLE_UNIT_TEST

BBUNIT_DEFINE_TEST(is_prefixed_with)
{
    BBUNIT_ASSERT_STREQ(" bar", is_prefixed_with("foo bar", "foo"));
    BBUNIT_ASSERT_STREQ("bar", is_prefixed_with("foo bar", "foo "));
    BBUNIT_ASSERT_STREQ("", is_prefixed_with("foo", "foo"));
    BBUNIT_ASSERT_STREQ("foo", is_prefixed_with("foo", ""));
    BBUNIT_ASSERT_STREQ("", is_prefixed_with("", ""));

    BBUNIT_ASSERT_NULL(is_prefixed_with("foo", "bar foo"));
    BBUNIT_ASSERT_NULL(is_prefixed_with("foo foo", "bar"));
    BBUNIT_ASSERT_NULL(is_prefixed_with("", "foo"));

    BBUNIT_ENDTEST;
}

BBUNIT_DEFINE_TEST(is_suffixed_with)
{
    BBUNIT_ASSERT_STREQ("bar", is_suffixed_with("foo bar", "bar"));
    BBUNIT_ASSERT_STREQ("foo", is_suffixed_with("foo", "foo"));
    BBUNIT_ASSERT_STREQ("", is_suffixed_with("foo", ""));
    BBUNIT_ASSERT_STREQ("", is_suffixed_with("", ""));
    BBUNIT_ASSERT_STREQ("foo", is_suffixed_with("barfoofoo", "foo"));

    BBUNIT_ASSERT_NULL(is_suffixed_with("foo", "bar foo"));
    BBUNIT_ASSERT_NULL(is_suffixed_with("foo foo", "bar"));
    BBUNIT_ASSERT_NULL(is_suffixed_with("", "foo"));

    BBUNIT_ENDTEST;
}

#endif /* ENABLE_UNIT_TEST */