/*      $NetBSD: util.c,v 1.19 2018/02/05 22:14:26 mrg Exp $    */
/*      $FreeBSD: head/usr.bin/grep/util.c 211496 2010-08-19 09:28:59Z des $    */
/*      $OpenBSD: util.c,v 1.39 2010/07/02 22:18:03 tedu Exp $  */

/*-
 * Copyright (c) 1999 James Howard and Dag-Erling Coïdan Smørgrav
 * Copyright (C) 2008-2010 Gabor Kovesdan <gabor@FreeBSD.org>
 * All rights reserved.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 */

#if HAVE_NBTOOL_CONFIG_H
#include "nbtool_config.h"
#endif

#include <sys/cdefs.h>
__RCSID("$NetBSD: util.c,v 1.19 2018/02/05 22:14:26 mrg Exp $");

#include <sys/stat.h>
#include <sys/types.h>

#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fnmatch.h>
#include <fts.h>
#include <libgen.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <wchar.h>
#include <wctype.h>

#include "grep.h"

static bool      first, first_global = true;
static unsigned long long since_printed;

static int       procline(struct str *l, int);

bool
file_matching(const char *fname)
{
        char *fname_base, *fname_copy;
        unsigned int i;
        bool ret;

        ret = finclude ? false : true;
        fname_copy = grep_strdup(fname);
        fname_base = basename(fname_copy);

        for (i = 0; i < fpatterns; ++i) {
                if (fnmatch(fpattern[i].pat, fname, 0) == 0 ||
                    fnmatch(fpattern[i].pat, fname_base, 0) == 0) {
                        if (fpattern[i].mode == EXCL_PAT) {
                                free(fname_copy);
                                return (false);
                        } else
                                ret = true;
                }
        }
        free(fname_copy);
        return (ret);
}

static inline bool
dir_matching(const char *dname)
{
        unsigned int i;
        bool ret;

        ret = dinclude ? false : true;

        for (i = 0; i < dpatterns; ++i) {
                if (dname != NULL &&
                    fnmatch(dname, dpattern[i].pat, 0) == 0) {
                        if (dpattern[i].mode == EXCL_PAT)
                                return (false);
                        else
                                ret = true;
                }
        }
        return (ret);
}

/*
 * Processes a directory when a recursive search is performed with
 * the -R option.  Each appropriate file is passed to procfile().
 */
int
grep_tree(char **argv)
{
        FTS *fts;
        FTSENT *p;
        char *d, *dir = NULL;
        int c, fts_flags;
        bool ok;

        c = fts_flags = 0;

        switch(linkbehave) {
        case LINK_EXPLICIT:
                fts_flags = FTS_COMFOLLOW;
                break;
        case LINK_SKIP:
                fts_flags = FTS_PHYSICAL;
                break;
        default:
                fts_flags = FTS_LOGICAL;
                        
        }

        fts_flags |= FTS_NOSTAT | FTS_NOCHDIR;

        if (!(fts = fts_open(argv, fts_flags, NULL)))
                err(2, "fts_open");
        while ((p = fts_read(fts)) != NULL) {
                switch (p->fts_info) {
                case FTS_DNR:
                        /* FALLTHROUGH */
                case FTS_ERR:
                        errx(2, "%s: %s", p->fts_path, strerror(p->fts_errno));
                        break;
                case FTS_D:
                        /* FALLTHROUGH */
                case FTS_DP:
                        break;
                case FTS_DC:
                        /* Print a warning for recursive directory loop */
                        warnx("warning: %s: recursive directory loop",
                                p->fts_path);
                        break;
                default:
                        /* Check for file exclusion/inclusion */
                        ok = true;
                        if (dexclude || dinclude) {
                                if ((d = strrchr(p->fts_path, '/')) != NULL) {
                                        dir = grep_malloc(sizeof(char) *
                                            (d - p->fts_path + 1));
                                        memcpy(dir, p->fts_path,
                                            d - p->fts_path);
                                        dir[d - p->fts_path] = '\0';
                                }
                                ok = dir_matching(dir);
                                free(dir);
                                dir = NULL;
                        }
                        if (fexclude || finclude)
                                ok &= file_matching(p->fts_path);

                        if (ok)
                                c += procfile(p->fts_path);
                        break;
                }
        }

        fts_close(fts);
        return (c);
}

/*
 * Opens a file and processes it.  Each file is processed line-by-line
 * passing the lines to procline().
 */
int
procfile(const char *fn)
{
        struct file *f;
        struct stat sb;
        struct str ln;
        mode_t s;
        int c, t;

        if (mflag && (mcount <= 0))
                return (0);

        if (strcmp(fn, "-") == 0) {
                fn = label != NULL ? label : getstr(1);
                f = grep_open(NULL);
        } else {
                if (!stat(fn, &sb)) {
                        /* Check if we need to process the file */
                        s = sb.st_mode & S_IFMT;
                        if (s == S_IFDIR && dirbehave == DIR_SKIP)
                                return (0);
                        if ((s == S_IFIFO || s == S_IFCHR || s == S_IFBLK
                                || s == S_IFSOCK) && devbehave == DEV_SKIP)
                                        return (0);
                }
                f = grep_open(fn);
        }
        if (f == NULL) {
                if (!sflag)
                        warn("%s", fn);
                if (errno == ENOENT)
                        notfound = true;
                return (0);
        }

        ln.file = grep_malloc(strlen(fn) + 1);
        strcpy(ln.file, fn);
        ln.line_no = 0;
        ln.len = 0;
        tail = 0;
        ln.off = -1;

        for (first = true, c = 0;  c == 0 || !(lflag || qflag); ) {
                ln.off += ln.len + 1;
                if ((ln.dat = grep_fgetln(f, &ln.len)) == NULL || ln.len == 0)
                        break;
                if (ln.len > 0 && ln.dat[ln.len - 1] == line_sep)
                        --ln.len;
                ln.line_no++;

                /* Return if we need to skip a binary file */
                if (f->binary && binbehave == BINFILE_SKIP) {
                        grep_close(f);
                        free(ln.file);
                        free(f);
                        return (0);
                }
                /* Process the file line-by-line */
                t = procline(&ln, f->binary);
                c += t;

                /* Count the matches if we have a match limit */
                if (mflag) {
                        mcount -= t;
                        if (mcount <= 0)
                                break;
                }
        }
        if (Bflag > 0)
                clearqueue();
        grep_close(f);

        if (cflag) {
                if (!hflag)
                        printf("%s:", ln.file);
                printf("%u%c", c, line_sep);
        }
        if (lflag && !qflag && c != 0)
                printf("%s%c", fn, line_sep);
        if (Lflag && !qflag && c == 0)
                printf("%s%c", fn, line_sep);
        if (c && !cflag && !lflag && !Lflag &&
            binbehave == BINFILE_BIN && f->binary && !qflag)
                printf(getstr(8), fn);

        free(ln.file);
        free(f);
        return (c);
}

#define iswword(x)      (iswalnum((x)) || (x) == L'_')

/*
 * Processes a line comparing it with the specified patterns.  Each pattern
 * is looped to be compared along with the full string, saving each and every
 * match, which is necessary to colorize the output and to count the
 * matches.  The matching lines are passed to printline() to display the
 * appropriate output.
 */
static int
procline(struct str *l, int nottext)
{
        regmatch_t matches[MAX_LINE_MATCHES];
        regmatch_t pmatch;
        size_t st = 0;
        unsigned int i;
        int c = 0, m = 0, r = 0;

        /* Loop to process the whole line */
        while (st <= l->len) {
                pmatch.rm_so = st;
                pmatch.rm_eo = l->len;

                /* Loop to compare with all the patterns */
                for (i = 0; i < patterns; i++) {
/*
 * XXX: grep_search() is a workaround for speed up and should be
 * removed in the future.  See fastgrep.c.
 */
                        if (fg_pattern[i].pattern) {
                                r = grep_search(&fg_pattern[i],
                                    (unsigned char *)l->dat,
                                    l->len, &pmatch);
                                r = (r == 0) ? 0 : REG_NOMATCH;
                                st = pmatch.rm_eo;
                        } else {
                                r = regexec(&r_pattern[i], l->dat, 1,
                                    &pmatch, eflags);
                                r = (r == 0) ? 0 : REG_NOMATCH;
                                st = pmatch.rm_eo;
                        }
                        if (r == REG_NOMATCH)
                                continue;
                        /* Check for full match */
                        if (xflag &&
                            (pmatch.rm_so != 0 ||
                             (size_t)pmatch.rm_eo != l->len))
                                continue;
                        /* Check for whole word match */
                        if (fg_pattern[i].word && pmatch.rm_so != 0) {
                                wchar_t wbegin, wend;

                                wbegin = wend = L' ';
                                if (pmatch.rm_so != 0 &&
                                    sscanf(&l->dat[pmatch.rm_so - 1],
                                    "%lc", &wbegin) != 1)
                                        continue;
                                if ((size_t)pmatch.rm_eo != l->len &&
                                    sscanf(&l->dat[pmatch.rm_eo],
                                    "%lc", &wend) != 1)
                                        continue;
                                if (iswword(wbegin) || iswword(wend))
                                        continue;
                        }
                        c = 1;
                        if (m < MAX_LINE_MATCHES)
                                matches[m++] = pmatch;
                        /* matches - skip further patterns */
                        if ((color != NULL && !oflag) || qflag || lflag)
                                break;
                }

                if (vflag) {
                        c = !c;
                        break;
                }
                /* One pass if we are not recording matches */
                if ((color != NULL && !oflag) || qflag || lflag)
                        break;

                if (st == (size_t)pmatch.rm_so)
                        break;  /* No matches */
        }

        if (c && binbehave == BINFILE_BIN && nottext)
                return (c); /* Binary file */

        /* Dealing with the context */
        if ((tail || c) && !cflag && !qflag && !lflag && !Lflag) {
                if (c) {
                        if ((Aflag || Bflag) && !first_global &&
                            (first || since_printed > Bflag))
                                printf("--\n");
                        tail = Aflag;
                        if (Bflag > 0)
                                printqueue();
                        printline(l, ':', matches, m);
                } else {
                        printline(l, '-', matches, m);
                        tail--;
                }
                first = false;
                first_global = false;
                since_printed = 0;
        } else {
                if (Bflag)
                        enqueue(l);
                since_printed++;
        }
        return (c);
}

/*
 * Safe malloc() for internal use.
 */
void *
grep_malloc(size_t size)
{
        void *ptr;

        if ((ptr = malloc(size)) == NULL)
                err(2, "malloc");
        return (ptr);
}

/*
 * Safe calloc() for internal use.
 */
void *
grep_calloc(size_t nmemb, size_t size)
{
        void *ptr;

        if ((ptr = calloc(nmemb, size)) == NULL)
                err(2, "calloc");
        return (ptr);
}

/*
 * Safe realloc() for internal use.
 */
void *
grep_realloc(void *ptr, size_t size)
{

        if ((ptr = realloc(ptr, size)) == NULL)
                err(2, "realloc");
        return (ptr);
}

/*
 * Safe strdup() for internal use.
 */
char *
grep_strdup(const char *str)
{
        char *ret;

        if ((ret = strdup(str)) == NULL)
                err(2, "strdup");
        return (ret);
}

/*
 * Prints a matching line according to the command line options.
 */
void
printline(struct str *line, int sep, regmatch_t *matches, int m)
{
        size_t a = 0;
        int i, n = 0;

        if (!hflag) {
                if (nullflag == 0)
                        fputs(line->file, stdout);
                else {
                        printf("%s", line->file);
                        putchar(0);
                }
                ++n;
        }
        if (nflag) {
                if (n > 0)
                        putchar(sep);
                printf("%d", line->line_no);
                ++n;
        }
        if (bflag) {
                if (n > 0)
                        putchar(sep);
                printf("%lld", (long long)line->off);
                ++n;
        }
        if (n)
                putchar(sep);
        /* --color and -o */
        if ((oflag || color) && m > 0) {
                for (i = 0; i < m; i++) {
                        if (!oflag)
                                fwrite(line->dat + a, matches[i].rm_so - a, 1,
                                    stdout);
                        if (color) 
                                fprintf(stdout, "\33[%sm\33[K", color);

                        fwrite(line->dat + matches[i].rm_so, 
                            matches[i].rm_eo - matches[i].rm_so, 1,
                            stdout);

                        if (color) 
                                fprintf(stdout, "\33[m\33[K");
                        a = matches[i].rm_eo;
                        if (oflag)
                                putchar('\n');
                }
                if (!oflag) {
                        if (line->len - a > 0)
                                fwrite(line->dat + a, line->len - a, 1, stdout);
                        putchar(line_sep);
                }
        } else {
                fwrite(line->dat, line->len, 1, stdout);
                putchar(line_sep);
        }
}