Subversion Repositories eco32

#include "c.h"

static char rcsid[] = "$Id: string.c,v 1.1 2002/08/28 23:12:46 drh Exp $";

static struct string {

        char *str;

        int len;

        struct string *link;

} *buckets[1024];

static int scatter[] = {        /* map characters to random values */

        2078917053, 143302914, 1027100827, 1953210302, 755253631,

        2002600785, 1405390230, 45248011, 1099951567, 433832350,

        2018585307, 438263339, 813528929, 1703199216, 618906479,

        573714703, 766270699, 275680090, 1510320440, 1583583926,

        1723401032, 1965443329, 1098183682, 1636505764, 980071615,

        1011597961, 643279273, 1315461275, 157584038, 1069844923,

        471560540, 89017443, 1213147837, 1498661368, 2042227746,

        1968401469, 1353778505, 1300134328, 2013649480, 306246424,

        1733966678, 1884751139, 744509763, 400011959, 1440466707,

        1363416242, 973726663, 59253759, 1639096332, 336563455,

        1642837685, 1215013716, 154523136, 593537720, 704035832,

        1134594751, 1605135681, 1347315106, 302572379, 1762719719,

        269676381, 774132919, 1851737163, 1482824219, 125310639,

        1746481261, 1303742040, 1479089144, 899131941, 1169907872,

        1785335569, 485614972, 907175364, 382361684, 885626931,

        200158423, 1745777927, 1859353594, 259412182, 1237390611,

        48433401, 1902249868, 304920680, 202956538, 348303940,

        1008956512, 1337551289, 1953439621, 208787970, 1640123668,

        1568675693, 478464352, 266772940, 1272929208, 1961288571,

        392083579, 871926821, 1117546963, 1871172724, 1771058762,

        139971187, 1509024645, 109190086, 1047146551, 1891386329,

        994817018, 1247304975, 1489680608, 706686964, 1506717157,

        579587572, 755120366, 1261483377, 884508252, 958076904,

        1609787317, 1893464764, 148144545, 1415743291, 2102252735,

        1788268214, 836935336, 433233439, 2055041154, 2109864544,

        247038362, 299641085, 834307717, 1364585325, 23330161,

        457882831, 1504556512, 1532354806, 567072918, 404219416,

        1276257488, 1561889936, 1651524391, 618454448, 121093252,

        1010757900, 1198042020, 876213618, 124757630, 2082550272,

        1834290522, 1734544947, 1828531389, 1982435068, 1002804590,

        1783300476, 1623219634, 1839739926, 69050267, 1530777140,

        1802120822, 316088629, 1830418225, 488944891, 1680673954,

        1853748387, 946827723, 1037746818, 1238619545, 1513900641,

        1441966234, 367393385, 928306929, 946006977, 985847834,

        1049400181, 1956764878, 36406206, 1925613800, 2081522508,

        2118956479, 1612420674, 1668583807, 1800004220, 1447372094,

        523904750, 1435821048, 923108080, 216161028, 1504871315,

        306401572, 2018281851, 1820959944, 2136819798, 359743094,

        1354150250, 1843084537, 1306570817, 244413420, 934220434,

        672987810, 1686379655, 1301613820, 1601294739, 484902984,

        139978006, 503211273, 294184214, 176384212, 281341425,

        228223074, 147857043, 1893762099, 1896806882, 1947861263,

        1193650546, 273227984, 1236198663, 2116758626, 489389012,

        593586330, 275676551, 360187215, 267062626, 265012701,

        719930310, 1621212876, 2108097238, 2026501127, 1865626297,

        894834024, 552005290, 1404522304, 48964196, 5816381,

        1889425288, 188942202, 509027654, 36125855, 365326415,

        790369079, 264348929, 513183458, 536647531, 13672163,

        313561074, 1730298077, 286900147, 1549759737, 1699573055,

        776289160, 2143346068, 1975249606, 1136476375, 262925046,

        92778659, 1856406685, 1884137923, 53392249, 1735424165,

        1602280572

};

char *string(const char *str) {

        const char *s;

        for (s = str; *s; s++)

                ;

        return stringn(str, s - str);

}

char *stringd(long n) {

        char str[25], *s = str + sizeof (str);

        unsigned long m;

        if (n == LONG_MIN)

                m = (unsigned long)LONG_MAX + 1;

        else if (n < 0)

                m = -n;

        else

                m = n;

        do

                *--s = m%10 + '0';

        while ((m /= 10) != 0);

        if (n < 0)

                *--s = '-';

        return stringn(s, str + sizeof (str) - s);

}

char *stringn(const char *str, int len) {

        int i;

        unsigned int h;

        const char *end;

        struct string *p;

        assert(str);

        for (h = 0, i = len, end = str; i > 0; i--)

                h = (h<<1) + scatter[*(unsigned char *)end++];

        h &= NELEMS(buckets)-1;

        for (p = buckets[h]; p; p = p->link)

                if (len == p->len) {

                        const char *s1 = str;

                        char *s2 = p->str;

                        do {

                                if (s1 == end)

                                        return p->str;

                        } while (*s1++ == *s2++);

                }

        {

                static char *next, *strlimit;

                if (len + 1 >= strlimit - next) {

                        int n = len + 4*1024;

                        next = allocate(n, PERM);

                        strlimit = next + n;

                }

                NEW(p, PERM);

                p->len = len;

                for (p->str = next; str < end; )

                        *next++ = *str++;

                *next++ = 0;

                p->link = buckets[h];

                buckets[h] = p;

                return p->str;

        }

}