/*      $OpenBSD: seq.c,v 1.14 2017/04/18 01:45:35 deraadt Exp $        */

/*-
 * Copyright (c) 1992, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 * Copyright (c) 1992, 1993, 1994, 1995, 1996
 *      Keith Bostic.  All rights reserved.
 *
 * See the LICENSE file for redistribution information.
 */

#include "config.h"

#include <sys/queue.h>

#include <bitstring.h>
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "common.h"

#define MINIMUM(a, b)   (((a) < (b)) ? (a) : (b))

/*
 * seq_set --
 *      Internal version to enter a sequence.
 *
 * PUBLIC: int seq_set(SCR *, CHAR_T *,
 * PUBLIC:    size_t, CHAR_T *, size_t, CHAR_T *, size_t, seq_t, int);
 */
int
seq_set(SCR *sp, CHAR_T *name, size_t nlen, CHAR_T *input, size_t ilen,
    CHAR_T *output, size_t olen, seq_t stype, int flags)
{
        CHAR_T *p;
        SEQ *lastqp, *qp;
        int sv_errno;

        /*
         * An input string must always be present.  The output string
         * can be NULL, when set internally, that's how we throw away
         * input.
         *
         * Just replace the output field if the string already set.
         */
        if ((qp =
            seq_find(sp, &lastqp, NULL, input, ilen, stype, NULL)) != NULL) {
                if (LF_ISSET(SEQ_NOOVERWRITE))
                        return (0);
                if (output == NULL || olen == 0) {
                        p = NULL;
                        olen = 0;
                } else if ((p = v_strdup(sp, output, olen)) == NULL) {
                        sv_errno = errno;
                        goto mem1;
                }
                free(qp->output);
                qp->olen = olen;
                qp->output = p;
                return (0);
        }

        /* Allocate and initialize SEQ structure. */
        CALLOC(sp, qp, 1, sizeof(SEQ));
        if (qp == NULL) {
                sv_errno = errno;
                goto mem1;
        }

        /* Name. */
        if (name == NULL || nlen == 0)
                qp->name = NULL;
        else if ((qp->name = v_strdup(sp, name, nlen)) == NULL) {
                sv_errno = errno;
                goto mem2;
        }
        qp->nlen = nlen;

        /* Input. */
        if ((qp->input = v_strdup(sp, input, ilen)) == NULL) {
                sv_errno = errno;
                goto mem3;
        }
        qp->ilen = ilen;

        /* Output. */
        if (output == NULL) {
                qp->output = NULL;
                olen = 0;
        } else if ((qp->output = v_strdup(sp, output, olen)) == NULL) {
                sv_errno = errno;
                free(qp->input);
mem3:           free(qp->name);
mem2:           free(qp);
mem1:           errno = sv_errno;
                msgq(sp, M_SYSERR, NULL);
                return (1);
        }
        qp->olen = olen;

        /* Type, flags. */
        qp->stype = stype;
        qp->flags = flags;

        /* Link into the chain. */
        if (lastqp == NULL) {
                LIST_INSERT_HEAD(&sp->gp->seqq, qp, q);
        } else {
                LIST_INSERT_AFTER(lastqp, qp, q);
        }

        /* Set the fast lookup bit. */
        if (qp->input[0] < MAX_BIT_SEQ)
                bit_set(sp->gp->seqb, qp->input[0]);

        return (0);
}

/*
 * seq_delete --
 *      Delete a sequence.
 *
 * PUBLIC: int seq_delete(SCR *, CHAR_T *, size_t, seq_t);
 */
int
seq_delete(SCR *sp, CHAR_T *input, size_t ilen, seq_t stype)
{
        SEQ *qp;

        if ((qp = seq_find(sp, NULL, NULL, input, ilen, stype, NULL)) == NULL)
                return (1);
        return (seq_mdel(qp));
}

/*
 * seq_mdel --
 *      Delete a map entry, without lookup.
 *
 * PUBLIC: int seq_mdel(SEQ *);
 */
int
seq_mdel(SEQ *qp)
{
        LIST_REMOVE(qp, q);
        free(qp->name);
        free(qp->input);
        free(qp->output);
        free(qp);
        return (0);
}

/*
 * seq_find --
 *      Search the sequence list for a match to a buffer, if ispartial
 *      isn't NULL, partial matches count.
 *
 * PUBLIC: SEQ *seq_find
 * PUBLIC:(SCR *, SEQ **, EVENT *, CHAR_T *, size_t, seq_t, int *);
 */
SEQ *
seq_find(SCR *sp, SEQ **lastqp, EVENT *e_input, CHAR_T *c_input, size_t ilen,
    seq_t stype, int *ispartialp)
{
        SEQ *lqp, *qp;
        int diff;

        /*
         * Ispartialp is a location where we return if there was a
         * partial match, i.e. if the string were extended it might
         * match something.
         *
         * XXX
         * Overload the meaning of ispartialp; only the terminal key
         * search doesn't want the search limited to complete matches,
         * i.e. ilen may be longer than the match.
         */
        if (ispartialp != NULL)
                *ispartialp = 0;
        for (lqp = NULL, qp = LIST_FIRST(&sp->gp->seqq);
            qp != NULL; lqp = qp, qp = LIST_NEXT(qp, q)) {
                /*
                 * Fast checks on the first character and type, and then
                 * a real comparison.
                 */
                if (e_input == NULL) {
                        if (qp->input[0] > c_input[0])
                                break;
                        if (qp->input[0] < c_input[0] ||
                            qp->stype != stype || F_ISSET(qp, SEQ_FUNCMAP))
                                continue;
                        diff = memcmp(qp->input, c_input, MINIMUM(qp->ilen, ilen));
                } else {
                        if (qp->input[0] > e_input->e_c)
                                break;
                        if (qp->input[0] < e_input->e_c ||
                            qp->stype != stype || F_ISSET(qp, SEQ_FUNCMAP))
                                continue;
                        diff =
                            e_memcmp(qp->input, e_input, MINIMUM(qp->ilen, ilen));
                }
                if (diff > 0)
                        break;
                if (diff < 0)
                        continue;
                /*
                 * If the entry is the same length as the string, return a
                 * match.  If the entry is shorter than the string, return a
                 * match if called from the terminal key routine.  Otherwise,
                 * keep searching for a complete match.
                 */
                if (qp->ilen <= ilen) {
                        if (qp->ilen == ilen || ispartialp != NULL) {
                                if (lastqp != NULL)
                                        *lastqp = lqp;
                                return (qp);
                        }
                        continue;
                }
                /*
                 * If the entry longer than the string, return partial match
                 * if called from the terminal key routine.  Otherwise, no
                 * match.
                 */
                if (ispartialp != NULL)
                        *ispartialp = 1;
                break;
        }
        if (lastqp != NULL)
                *lastqp = lqp;
        return (NULL);
}

/*
 * seq_close --
 *      Discard all sequences.
 *
 * PUBLIC: void seq_close(GS *);
 */
void
seq_close(GS *gp)
{
        SEQ *qp;

        while ((qp = LIST_FIRST(&gp->seqq)) != NULL) {
                free(qp->name);
                free(qp->input);
                free(qp->output);
                LIST_REMOVE(qp, q);
                free(qp);
        }
}

/*
 * seq_dump --
 *      Display the sequence entries of a specified type.
 *
 * PUBLIC: int seq_dump(SCR *, seq_t, int);
 */
int
seq_dump(SCR *sp, seq_t stype, int isname)
{
        CHAR_T *p;
        GS *gp;
        SEQ *qp;
        int cnt, len, olen;

        cnt = 0;
        gp = sp->gp;
        LIST_FOREACH(qp, &gp->seqq, q) {
                if (stype != qp->stype || F_ISSET(qp, SEQ_FUNCMAP))
                        continue;
                ++cnt;
                for (p = qp->input,
                    olen = qp->ilen, len = 0; olen > 0; --olen, ++p)
                        len += ex_puts(sp, KEY_NAME(sp, *p));
                for (len = STANDARD_TAB - len % STANDARD_TAB; len > 0;)
                        len -= ex_puts(sp, " ");

                if (qp->output != NULL)
                        for (p = qp->output,
                            olen = qp->olen, len = 0; olen > 0; --olen, ++p)
                                len += ex_puts(sp, KEY_NAME(sp, *p));
                else
                        len = 0;

                if (isname && qp->name != NULL) {
                        for (len = STANDARD_TAB - len % STANDARD_TAB; len > 0;)
                                len -= ex_puts(sp, " ");
                        for (p = qp->name,
                            olen = qp->nlen; olen > 0; --olen, ++p)
                                (void)ex_puts(sp, KEY_NAME(sp, *p));
                }
                (void)ex_puts(sp, "\n");
        }
        return (cnt);
}

/*
 * seq_save --
 *      Save the sequence entries to a file.
 *
 * PUBLIC: int seq_save(SCR *, FILE *, char *, seq_t);
 */
int
seq_save(SCR *sp, FILE *fp, char *prefix, seq_t stype)
{
        CHAR_T *p;
        SEQ *qp;
        size_t olen;
        int ch;

        /* Write a sequence command for all keys the user defined. */
        LIST_FOREACH(qp, &sp->gp->seqq, q) {
                if (stype != qp->stype || !F_ISSET(qp, SEQ_USERDEF))
                        continue;
                if (prefix)
                        (void)fprintf(fp, "%s", prefix);
                for (p = qp->input, olen = qp->ilen; olen > 0; --olen) {
                        ch = *p++;
                        if (ch == CH_LITERAL || ch == '|' ||
                            isblank(ch) || KEY_VAL(sp, ch) == K_NL)
                                (void)putc(CH_LITERAL, fp);
                        (void)putc(ch, fp);
                }
                (void)putc(' ', fp);
                if (qp->output != NULL)
                        for (p = qp->output,
                            olen = qp->olen; olen > 0; --olen) {
                                ch = *p++;
                                if (ch == CH_LITERAL || ch == '|' ||
                                    KEY_VAL(sp, ch) == K_NL)
                                        (void)putc(CH_LITERAL, fp);
                                (void)putc(ch, fp);
                        }
                (void)putc('\n', fp);
        }
        return (0);
}

/*
 * e_memcmp --
 *      Compare a string of EVENT's to a string of CHAR_T's.
 *
 * PUBLIC: int e_memcmp(CHAR_T *, EVENT *, size_t);
 */
int
e_memcmp(CHAR_T *p1, EVENT *ep, size_t n)
{
        if (n != 0) {
                do {
                        if (*p1++ != ep->e_c)
                                return (*--p1 - ep->e_c);
                        ++ep;
                } while (--n != 0);
        }
        return (0);
}