/*      $OpenBSD: fastfind.c,v 1.17 2023/04/28 20:22:35 tb Exp $        */

/*
 * Copyright (c) 1995 Wolfram Schneider <wosch@FreeBSD.org>. Berlin.
 * Copyright (c) 1989, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * James A. Woods.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef _LOCATE_STATISTIC_
#define _LOCATE_STATISTIC_

void
statistic (FILE *fp, char *path_fcodes)
{
        int lines, chars, size, big, zwerg;
        u_char *p, *s;
        int c;
        int count, umlaut;
        u_char bigram1[NBG], bigram2[NBG], path[PATH_MAX];

        for (c = 0, p = bigram1, s = bigram2; c < NBG; c++) {
                p[c] = check_bigram_char(getc(fp));
                s[c] = check_bigram_char(getc(fp));
        }

        lines = chars = big = zwerg = umlaut = 0;
        size = NBG + NBG;

        for (c = getc(fp), count = 0; c != EOF; size++) {
                if (c == SWITCH) {
                        count += getwf(fp) - OFFSET;
                        size += sizeof(int);
                        zwerg++;
                } else
                        count += c - OFFSET;

                sane_count(count);
                for (p = path + count; (c = getc(fp)) > SWITCH; size++)
                        if (c < PARITY) {
                                if (c == UMLAUT) {
                                        c = getc(fp);
                                        size++;
                                        umlaut++;
                                }
                                p++;
                        } else {
                                /* bigram char */
                                big++;
                                p += 2;
                        }

                p++;
                lines++;
                chars += (p - path);
        }

        (void)printf("\nDatabase: %s\n", path_fcodes);
        (void)printf("Compression: Front: %2.2f%%, ",
            (float)(100 * (size + big - (2 * NBG))) / chars);
        (void)printf("Bigram: %2.2f%%, ", (float)(100 * (size - big)) / size);
        (void)printf("Total: %2.2f%%\n",
            (float)(100 * (size - (2 * NBG))) / chars);
        (void)printf("Filenames: %d, ", lines);
        (void)printf("Characters: %d, ", chars);
        (void)printf("Database size: %d\n", size);
        (void)printf("Bigram characters: %d, ", big);
        (void)printf("Integers: %d, ", zwerg);
        (void)printf("8-Bit characters: %d\n", umlaut);

}
#endif /* _LOCATE_STATISTIC_ */


void


#ifdef FF_ICASE
fastfind_mmap_icase
#else
fastfind_mmap
#endif /* FF_ICASE */
(char *pathpart, caddr_t paddr, int len, char *database)
{
        u_char *p, *s, *patend, *q, *foundchar;
        int c, cc;
        int count, found, globflag;
        u_char *cutoff;
        u_char bigram1[NBG], bigram2[NBG], path[PATH_MAX];

#ifdef FF_ICASE
        for (p = pathpart; *p != '\0'; p++)
                *p = tolower(*p);
#endif /* FF_ICASE*/

        /* init bigram table */
        if (len < (2*NBG)) {
                (void)fprintf(stderr, "database too small: %s\n", database);
                exit(1);
        }

        for (c = 0, p = bigram1, s = bigram2; c < NBG; c++, len-= 2) {
                p[c] = check_bigram_char(*paddr++);
                s[c] = check_bigram_char(*paddr++);
        }

        /* find optimal (last) char for searching */
        for (p = pathpart; *p != '\0'; p++)
                if (strchr(LOCATE_REG, *p) != NULL)
                        break;

        if (*p == '\0')
                globflag = 0;
        else
                globflag = 1;

        p = pathpart;
        patend = patprep(p);
        cc = *patend;
#ifdef FF_ICASE
        cc = tolower(cc);
#endif /* FF_ICASE */


        /* main loop */
        found = count = 0;
        foundchar = 0;

        c = (u_char)*paddr++; len--;
        for (; len > 0; ) {

                /* go forward or backward */
                if (c == SWITCH) { /* big step, an integer */
                        if (len < sizeof(int))
                                break;
                        count += getwm(paddr) - OFFSET;
                        len -= sizeof(int);
                        paddr += sizeof(int);
                } else {           /* slow step, =< 14 chars */
                        count += c - OFFSET;
                }

                sane_count(count);
                /* overlay old path */
                p = path + count;
                foundchar = p - 1;

                for (; len > 0; ) {
                        c = (u_char)*paddr++;
                        len--;
                        /*
                         * == UMLAUT: 8 bit char followed
                         * <= SWITCH: offset
                         * >= PARITY: bigram
                         * rest:      single ascii char
                         *
                         * offset < SWITCH < UMLAUT < ascii < PARITY < bigram
                         */
                        if (c < PARITY) {
                                if (c <= UMLAUT) {
                                        if (c == UMLAUT && len > 0) {
                                                c = (u_char)*paddr++;
                                                len--;

                                        } else
                                                break; /* SWITCH */
                                }
#ifdef FF_ICASE
                                if (tolower(c) == cc)
#else
                                if (c == cc)
#endif /* FF_ICASE */
                                        foundchar = p;
                                *p++ = c;
                        } else {
                                /* bigrams are parity-marked */
                                c &= ASCII_MAX;
#ifdef FF_ICASE
                                if (tolower(bigram1[c]) == cc ||
                                    tolower(bigram2[c]) == cc)
#else
                                if (bigram1[c] == cc ||
                                    bigram2[c] == cc)
#endif /* FF_ICASE */
                                        foundchar = p + 1;

                                *p++ = bigram1[c];
                                *p++ = bigram2[c];
                        }
                }

                if (found) {                    /* previous line matched */
                        cutoff = path;
                        *p-- = '\0';
                        foundchar = p;
                } else if (foundchar >= path + count) { /* a char matched */
                        *p-- = '\0';
                        cutoff = path + count;
                } else                          /* nothing to do */
                        continue;

                found = 0;
                for (s = foundchar; s >= cutoff; s--) {
                        if (*s == cc
#ifdef FF_ICASE
                            || tolower(*s) == cc
#endif /* FF_ICASE */
                            ) { /* fast first char check */
                                for (p = patend - 1, q = s - 1; *p != '\0';
                                    p--, q--)
                                        if (*q != *p
#ifdef FF_ICASE
                                            && tolower(*q) != *p
#endif /* FF_ICASE */
                                            )
                                                break;
                                if (*p == '\0') {   /* fast match success */
                                        char    *shortpath;

                                        found = 1;
                                        shortpath = path;
                                        if (f_basename)
                                                shortpath = basename(path);

                                        if ((!f_basename && (!globflag ||
#ifdef FF_ICASE
                                            !fnmatch(pathpart, shortpath,
                                                FNM_CASEFOLD)))
#else
                                            !fnmatch(pathpart, shortpath, 0)))
#endif /* FF_ICASE */
                                            || (strstr(shortpath, pathpart) !=
                                            NULL)) {
                                                if (f_silent)
                                                        counter++;
                                                else if (f_limit) {
                                                        counter++;
                                                        if (f_limit >= counter)
                                                                (void)puts(path);
                                                        else  {
                                                                fprintf(stderr, "[show only %u lines]\n", counter - 1);
                                                                exit(0);
                                                        }
                                                } else
                                                        (void)puts(path);
                                        }
                                        break;
                                }
                        }
                }
        }
}