/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
 */

#include <dirent.h>
#include <fnmatch.h>
#include <string.h>
#include "bart.h"

static int count_slashes(const char *);
static struct rule *gen_rulestruct(void);
static struct tree_modifier *gen_tree_modifier(void);
static struct dir_component *gen_dir_component(void);
static void init_rule(uint_t, struct rule *);
static void add_modifier(struct rule *, char *);
static struct rule *add_subtree_rule(char *, char *, int, int *);
static struct rule *add_single_rule(char *);
static void dirs_cleanup(struct dir_component *);
static void add_dir(struct dir_component **, char *);
static char *lex(FILE *);
static int match_subtree(const char *, char *);
static struct rule *get_last_entry(boolean_t);

static int      lex_linenum;    /* line number in current input file    */
static struct rule      *first_rule = NULL, *current_rule = NULL;

/*
 * This function is responsible for validating whether or not a given file
 * should be cataloged, based upon the modifiers for a subtree.
 * For example, a line in the rules file: '/home/nickiso *.c' should only
 * catalog the C files (based upon pattern matching) in the subtree
 * '/home/nickiso'.
 *
 * exclude_fname depends on having the modifiers be pre-sorted to put
 * negative directory modifiers first, so that the logic does
 * not need to save complex state information.  This is valid because
 * we are only cataloging things that meet all modifiers (AND logic.)
 *
 * Returns:
 * NO_EXCLUDE
 * EXCLUDE_SKIP
 * EXCLUDE_PRUNE
 */
int
exclude_fname(const char *fname, char fname_type, struct rule *rule_ptr)
{
        char    *pattern, *ptr, *fname_ptr, saved_char;
        char    fname_cp[PATH_MAX], pattern_cp[PATH_MAX];
        int     num_pattern_slash,  i, num_fname_slash, slashes_to_adv;
        struct  tree_modifier   *mod_ptr;

        /*
         * If this is create and there are no modifiers, bail.
         * This will have to change once create handles multiple rules
         * during walk.
         */
        if (rule_ptr->modifiers == NULL)
                if (rule_ptr->attr_list == 0)
                        return (EXCLUDE_PRUNE);
                else
                        return (NO_EXCLUDE);
        /*
         * Walk through all the modifiers until its they are exhausted OR
         * until the file should definitely be excluded.
         */
        for (mod_ptr = rule_ptr->modifiers; mod_ptr != NULL;
            mod_ptr = mod_ptr->next) {
                /* leading !'s were processed in add_modifier */
                pattern = mod_ptr->mod_str;
                if (mod_ptr->is_dir == B_FALSE) {
                        /*
                         * Pattern is a file pattern.
                         *
                         * In the case when a user is trying to filter on
                         * a file pattern and the entry is a directory,
                         * this is not a match.
                         *
                         * If a match is required, skip this file.  If
                         * a match is forbidden, keep looking at modifiers.
                         */
                        if (fname_type == 'D') {
                                if (mod_ptr->include == B_TRUE)
                                        return (EXCLUDE_SKIP);
                                else
                                        continue;
                        }

                        /*
                         * Match patterns against filenames.
                         * Need to be able to handle multi-level patterns,
                         * eg. "SCCS/<star-wildcard>.c", which means
                         * 'only match C files under SCCS directories.
                         *
                         * Determine the number of levels in the filename and
                         * in the pattern.
                         */
                        num_pattern_slash = count_slashes(pattern);
                        num_fname_slash = count_slashes(fname);

                        /* Check for trivial exclude condition */
                        if (num_pattern_slash > num_fname_slash) {
                                if (mod_ptr->include == B_TRUE)
                                        return (EXCLUDE_SKIP);
                        }

                        /*
                         * Do an apples to apples comparison, based upon the
                         * number of levels:
                         *
                         * Assume fname is /A/B/C/D/E and the pattern is D/E.
                         * In that case, 'ptr' will point to "D/E" and
                         * 'slashes_to_adv' will be '4'.
                         */
                        (void) strlcpy(fname_cp, fname, sizeof (fname_cp));
                        ptr = fname_cp;
                        slashes_to_adv = num_fname_slash - num_pattern_slash;
                        for (i = 0; i < slashes_to_adv; i++)  {
                                ptr = strchr(ptr, '/');
                                ptr++;
                        }
                        if ((pattern[0] == '.') && (pattern[1] == '.') &&
                            (pattern[2] == '/')) {
                                pattern = strchr(pattern, '/');
                                ptr = strchr(ptr, '/');
                        }


                        /* OK, now do the fnmatch() compare to the file */
                        if (fnmatch(pattern, ptr, FNM_PATHNAME) == 0) {
                                /* matches, is it an exclude? */
                                if (mod_ptr->include == B_FALSE)
                                        return (EXCLUDE_SKIP);
                        } else if (mod_ptr->include == B_TRUE) {
                                /* failed a required filename match */
                                return (EXCLUDE_SKIP);
                        }
                } else {
                        /*
                         * The rule requires directory matching.
                         *
                         * Unlike filename matching, directory matching can
                         * prune.
                         *
                         * First, make copies, since both the pattern and
                         * filename need to be modified.
                         *
                         * When copying 'fname', ignore the relocatable root
                         * since pattern matching is done for the string AFTER
                         * the relocatable root.  For example, if the
                         * relocatable root is "/dir1/dir2/dir3" and the
                         * pattern is "dir3/", we do NOT want to include every
                         * directory in the relocatable root.  Instead, we
                         * only want to include subtrees that look like:
                         * "/dir1/dir2/dir3/....dir3/....."
                         *
                         * NOTE: the 'fname_cp' does NOT have a trailing '/':
                         * necessary for fnmatch().
                         */
                        (void) strlcpy(fname_cp,
                            (fname+strlen(rule_ptr->subtree)),
                            sizeof (fname_cp));
                        (void) strlcpy(pattern_cp, pattern,
                            sizeof (pattern_cp));

                        /*
                         * For non-directory files, remove the trailing
                         * name, e.g., for a file /A/B/C/D where 'D' is
                         * the actual filename, remove the 'D' since it
                         * should *not* be considered in the directory match.
                         */
                        if (fname_type != 'D') {
                                ptr = strrchr(fname_cp, '/');
                                if (ptr != NULL)
                                        *ptr = '\0';

                                /*
                                 * Trivial case: a simple filename does
                                 * not match a directory by definition,
                                 * so skip if match is required,
                                 * keep analyzing otherwise.
                                 */

                                if (strlen(fname_cp) == 0)
                                        if (mod_ptr->include == B_TRUE)
                                                return (EXCLUDE_SKIP);
                        }

                        /* Count the # of slashes in the pattern and fname */
                        num_pattern_slash = count_slashes(pattern_cp);
                        num_fname_slash = count_slashes(fname_cp);

                        /*
                         * fname_cp is too short if this is not a dir
                         */
                        if ((num_pattern_slash > num_fname_slash) &&
                            (fname_type != 'D')) {
                                if (mod_ptr->include == B_TRUE)
                                        return (EXCLUDE_SKIP);
                        }


                        /*
                         * Take the leading '/' from fname_cp before
                         * decrementing the number of slashes.
                         */
                        if (fname_cp[0] == '/') {
                                (void) strlcpy(fname_cp,
                                    strchr(fname_cp, '/') + 1,
                                    sizeof (fname_cp));
                                num_fname_slash--;
                        }

                        /*
                         * Begin the loop, walk through the file name until
                         * it can be determined that there is no match.
                         * For example: if pattern is C/D/, and fname_cp is
                         * A/B/C/D/E then compare A/B/ with C/D/, if it doesn't
                         * match, then walk further so that the next iteration
                         * checks B/C/ against C/D/, continue until we have
                         * exhausted options.
                         * In the above case, the 3rd iteration will match
                         * C/D/ with C/D/.
                         */
                        while (num_pattern_slash <= num_fname_slash) {
                                /* get a pointer to our filename */
                                fname_ptr = fname_cp;

                                /*
                                 * Walk the filename through the slashes
                                 * so that we have a component of the same
                                 * number of slashes as the pattern.
                                 */

                                for (i = 0; i < num_pattern_slash; i++) {
                                        ptr = strchr(fname_ptr, '/');
                                        fname_ptr = ptr + 1;
                                }

                                /*
                                 * Save the character after our target slash
                                 * before breaking the string for use with
                                 * fnmatch
                                 */
                                saved_char = *(++ptr);

                                *ptr = '\0';

                                /*
                                 * Call compare function for the current
                                 * component with the pattern we are looking
                                 * for.
                                 */
                                if (fnmatch(pattern_cp, fname_cp,
                                    FNM_PATHNAME) == 0) {
                                        if (mod_ptr->include == B_TRUE) {
                                                break;
                                        } else if (fname_type == 'D')
                                                return (EXCLUDE_PRUNE);
                                        else
                                                return (EXCLUDE_SKIP);
                                } else if (mod_ptr->include == B_TRUE) {
                                        if (fname_type == 'D')
                                                return (EXCLUDE_PRUNE);
                                        else
                                                return (EXCLUDE_SKIP);
                                }
                                /*
                                 * We didn't match, so restore the saved
                                 * character to the original position.
                                 */
                                *ptr = saved_char;

                                /*
                                 * Break down fname_cp, if it was A/B/C
                                 * then after this operation it will be B/C
                                 * in preparation for the next iteration.
                                 */
                                (void) strlcpy(fname_cp,
                                    strchr(fname_cp, '/') + 1,
                                    sizeof (fname_cp));

                                /*
                                 * Decrement the number of slashes to
                                 * compensate for the one removed above.
                                 */
                                num_fname_slash--;
                        } /* end while loop looking down the path */

                        /*
                         * If we didn't get a match above then we may be on the
                         * last component of our filename.
                         * This is to handle the following cases
                         *    - filename is A/B/C/D/E and pattern may be D/E/
                         *    - filename is D/E and pattern may be D/E/
                         */
                        if (num_pattern_slash == (num_fname_slash + 1)) {

                                /* strip the trailing slash from the pattern */
                                ptr = strrchr(pattern_cp, '/');
                                *ptr = '\0';

                                /* fnmatch returns 0 for a match */
                                if (fnmatch(pattern_cp, fname_cp,
                                    FNM_PATHNAME) == 0) {
                                        if (mod_ptr->include == B_FALSE) {
                                                if (fname_type == 'D')
                                                        return (EXCLUDE_PRUNE);
                                                else
                                                        return (EXCLUDE_SKIP);
                                        }
                                } else if (mod_ptr->include == B_TRUE)
                                        return (EXCLUDE_SKIP);

                        }

                }
        }
        return (NO_EXCLUDE);
}

static int
count_slashes(const char *in_path)
{
        int num_fname_slash = 0;
        const char *p;
        for (p = in_path; *p != '\0'; p++)
                if (*p == '/')
                        num_fname_slash++;
        return (num_fname_slash);
}

static struct rule *
gen_rulestruct(void)
{
        struct rule     *new_rule;

        new_rule = (struct rule *)safe_calloc(sizeof (struct rule));
        return (new_rule);
}

static struct tree_modifier *
gen_tree_modifier(void)
{
        struct tree_modifier    *new_modifier;

        new_modifier = (struct tree_modifier *)safe_calloc
            (sizeof (struct tree_modifier));
        return (new_modifier);
}

static struct dir_component *
gen_dir_component(void)
{
        struct dir_component    *new_dir;

        new_dir = (struct dir_component *)safe_calloc
            (sizeof (struct dir_component));
        return (new_dir);
}

/*
 * Set up a default rule when there is no rules file.
 */
static struct rule *
setup_default_rule(char *reloc_root, uint_t flags)
{
        struct  rule    *new_rule;

        new_rule = add_single_rule(reloc_root[0] == '\0' ? "/" : reloc_root);
        init_rule(flags, new_rule);
        add_modifier(new_rule, "*");

        return (new_rule);
}

/*
 * Utility function, used to initialize the flag in a new rule structure.
 */
static void
init_rule(uint_t flags, struct rule *new_rule)
{

        if (new_rule == NULL)
                return;
        new_rule->attr_list = flags;
}

/*
 * Function to read the rulesfile.  Used by both 'bart create' and
 * 'bart compare'.
 */
int
read_rules(FILE *file, char *reloc_root, uint_t in_flags, int create)
{
        char            *s;
        struct rule     *block_begin = NULL, *new_rule, *rp;
        struct attr_keyword *akp;
        int             check_flag, ignore_flag, syntax_err, ret_code;
        int             global_block;

        ret_code = EXIT;

        lex_linenum = 0;
        check_flag = 0;
        ignore_flag = 0;
        syntax_err = 0;
        global_block = 1;

        if (file == NULL) {
                (void) setup_default_rule(reloc_root, in_flags);
                return (ret_code);
        } else if (!create) {
                block_begin = setup_default_rule("/", in_flags);
        }

        while (!feof(file)) {
                /* Read a line from the file */
                s = lex(file);

                /* skip blank lines and comments */
                if (s == NULL || *s == 0 || *s == '#')
                        continue;

                /*
                 * Beginning of a subtree and possibly a new block.
                 *
                 * If this is a new block, keep track of the beginning of
                 * the block. if there are directives later on, we need to
                 * apply that directive to all members of the block.
                 *
                 * If the first stmt in the file was an 'IGNORE all' or
                 * 'IGNORE contents', we need to keep track of it and
                 * automatically switch off contents checking for new
                 * subtrees.
                 */
                if (s[0] == '/') {
                        /* subtree definition hence not a global block */
                        global_block = 0;

                        new_rule = add_subtree_rule(s, reloc_root, create,
                            &ret_code);

                        s = lex(0);
                        while ((s != NULL) && (*s != 0) && (*s != '#')) {
                                add_modifier(new_rule, s);
                                s = lex(0);
                        }

                        /* Found a new block, keep track of the beginning */
                        if (block_begin == NULL ||
                            (ignore_flag != 0) || (check_flag != 0)) {
                                block_begin = new_rule;
                                check_flag = 0;
                                ignore_flag = 0;
                        }

                        /* Apply global settings to this block, if any */
                        init_rule(in_flags, new_rule);
                } else if (IGNORE_KEYWORD(s) || CHECK_KEYWORD(s)) {
                        int check_kw;

                        if (IGNORE_KEYWORD(s)) {
                                ignore_flag++;
                                check_kw = 0;
                        } else {
                                check_flag++;
                                check_kw = 1;
                        }

                        /* Parse next token */
                        s = lex(0);
                        while ((s != NULL) && (*s != 0) && (*s != '#')) {
                                akp = attr_keylookup(s);
                                if (akp == NULL) {
                                        (void) fprintf(stderr, SYNTAX_ERR, s);
                                        syntax_err++;
                                        exit(2);
                                }

                                /*
                                 * For all the flags, check if this is a global
                                 * IGNORE/CHECK. If so, set the global flags.
                                 *
                                 * NOTE: The only time you can have a
                                 * global ignore is when its the
                                 * stmt before any blocks have been
                                 * spec'd.
                                 */
                                if (global_block) {
                                        if (check_kw)
                                                in_flags |= akp->ak_flags;
                                        else
                                                in_flags &= ~(akp->ak_flags);
                                } else {
                                        for (rp = block_begin; rp != NULL;
                                            rp = rp->next) {
                                                if (check_kw)
                                                        rp->attr_list |=
                                                            akp->ak_flags;
                                                else
                                                        rp->attr_list &=
                                                            ~(akp->ak_flags);
                                        }
                                }

                                /* Parse next token */
                                s = lex(0);
                        }
                } else {
                        (void) fprintf(stderr, SYNTAX_ERR, s);
                        s = lex(0);
                        while (s != NULL && *s != 0) {
                                (void) fprintf(stderr, " %s", s);
                                s = lex(0);
                        }
                        (void) fprintf(stderr, "\n");
                        syntax_err++;
                }
        }

        (void) fclose(file);

        if (syntax_err) {
                (void) fprintf(stderr, SYNTAX_ABORT);
                exit(2);
        }

        return (ret_code);
}
/*
 * Add a modifier to the mod_ptr list in each rule, putting negative
 * directory entries
 * first to guarantee walks will be appropriately pruned.
 */
static void
add_modifier(struct rule *rule, char *modifier_str)
{
        int     include, is_dir;
        char    *pattern;
        struct tree_modifier    *new_mod_ptr, *curr_mod_ptr;
        struct rule             *this_rule;

        include = B_TRUE;
        pattern = modifier_str;

        /* see if the pattern is an include or an exclude */
        if (pattern[0] == '!') {
                include = B_FALSE;
                pattern++;
        }

        is_dir = (pattern[0] != '\0' && pattern[strlen(pattern) - 1] == '/');

        for (this_rule = rule; this_rule != NULL; this_rule = this_rule->next) {
                new_mod_ptr = gen_tree_modifier();
                new_mod_ptr->include = include;
                new_mod_ptr->is_dir = is_dir;
                new_mod_ptr->mod_str = safe_strdup(pattern);

                if (is_dir && !include) {
                        new_mod_ptr->next = this_rule->modifiers;
                        this_rule->modifiers = new_mod_ptr;
                } else if (this_rule->modifiers == NULL)
                        this_rule->modifiers = new_mod_ptr;
                else {
                        curr_mod_ptr = this_rule->modifiers;
                        while (curr_mod_ptr->next != NULL)
                                curr_mod_ptr = curr_mod_ptr->next;

                        curr_mod_ptr->next = new_mod_ptr;
                }
        }
}

/*
 * This funtion is invoked when reading rulesfiles.  A subtree may have
 * wildcards in it, e.g., '/home/n*', which is expected to match all home
 * dirs which start with an 'n'.
 *
 * This function needs to break down the subtree into its components.  For
 * each component, see how many directories match.  Take the subtree list just
 * generated and run it through again, this time looking at the next component.
 * At each iteration, keep a linked list of subtrees that currently match.
 * Once the final list is created, invoke add_single_rule() to create the
 * rule struct with the correct information.
 *
 * This function returns a ptr to the first element in the block of subtrees
 * which matched the subtree def'n in the rulesfile.
 */
static struct rule *
add_subtree_rule(char *rule, char *reloc_root, int create, int *err_code)
{
        char                    full_path[PATH_MAX], pattern[PATH_MAX];
        char                    new_dirname[PATH_MAX];
        char                    *beg_pattern, *end_pattern, *curr_dirname;
        struct  dir_component   *current_level = NULL, *next_level = NULL;
        struct  dir_component   *tmp_ptr;
        DIR                     *dir_ptr;
        struct dirent           *dir_entry;
        struct rule             *begin_rule = NULL;
        int                     ret;
        struct stat64           statb;

        (void) snprintf(full_path, sizeof (full_path),
            (rule[0] == '/') ? "%s%s" : "%s/%s", reloc_root, rule);

        /*
         * In the case of 'bart compare', don't validate
         * the subtrees, since the machine running the
         * comparison may not be the machine which generated
         * the manifest.
         */
        if (create == 0)
                return (add_single_rule(full_path));


        /* Insert 'current_level' into the linked list */
        add_dir(&current_level, NULL);

        /* Special case: occurs when -R is "/" and the subtree is "/" */
        if (strcmp(full_path, "/") == 0)
                (void) strcpy(current_level->dirname, "/");

        beg_pattern = full_path;

        while (beg_pattern != NULL) {
                /*
                 * Extract the pathname component starting at 'beg_pattern'.
                 * Take those chars and put them into 'pattern'.
                 */
                while (*beg_pattern == '/')
                        beg_pattern++;
                if (*beg_pattern == '\0')       /* end of pathname */
                        break;
                end_pattern = strchr(beg_pattern, '/');
                if (end_pattern != NULL)
                        (void) strlcpy(pattern, beg_pattern,
                            end_pattern - beg_pattern + 1);
                else
                        (void) strlcpy(pattern, beg_pattern, sizeof (pattern));
                beg_pattern = end_pattern;

                /*
                 * At this point, search for 'pattern' as a *subdirectory* of
                 * the dirs in the linked list.
                 */
                while (current_level != NULL) {
                        /* curr_dirname used to make the code more readable */
                        curr_dirname = current_level->dirname;

                        /* Initialization case */
                        if (strlen(curr_dirname) == 0)
                                (void) strcpy(curr_dirname, "/");

                        /* Open up the dir for this element in the list */
                        dir_ptr = opendir(curr_dirname);
                        dir_entry = NULL;

                        if (dir_ptr == NULL) {
                                perror(curr_dirname);
                                *err_code = WARNING_EXIT;
                        } else
                                dir_entry = readdir(dir_ptr);

                        /*
                         * Now iterate through the subdirs of 'curr_dirname'
                         * In the case of a match against 'pattern',
                         * add the path to the next linked list, which
                         * will be matched on the next iteration.
                         */
                        while (dir_entry != NULL) {
                                /* Skip the dirs "." and ".." */
                                if ((strcmp(dir_entry->d_name, ".") == 0) ||
                                    (strcmp(dir_entry->d_name, "..") == 0)) {
                                        dir_entry = readdir(dir_ptr);
                                        continue;
                                }
                                if (fnmatch(pattern, dir_entry->d_name,
                                    FNM_PATHNAME) == 0) {
                                        /*
                                         * Build 'new_dirname' which will be
                                         * examined on the next iteration.
                                         */
                                        if (curr_dirname[strlen(curr_dirname)-1]
                                            != '/')
                                                (void) snprintf(new_dirname,
                                                    sizeof (new_dirname),
                                                    "%s/%s", curr_dirname,
                                                    dir_entry->d_name);
                                        else
                                                (void) snprintf(new_dirname,
                                                    sizeof (new_dirname),
                                                    "%s%s", curr_dirname,
                                                    dir_entry->d_name);

                                        /* Add to the next lined list */
                                        add_dir(&next_level, new_dirname);
                                }
                                dir_entry = readdir(dir_ptr);
                        }

                        /* Close directory */
                        if (dir_ptr != NULL)
                                (void) closedir(dir_ptr);

                        /* Free this entry and move on.... */
                        tmp_ptr = current_level;
                        current_level = current_level->next;
                        free(tmp_ptr);
                }

                /*
                 * OK, done with this level.  Move to the next level and
                 * advance the ptrs which indicate the component name.
                 */
                current_level = next_level;
                next_level = NULL;
        }

        tmp_ptr = current_level;

        /* Error case: the subtree doesn't exist! */
        if (current_level == NULL) {
                (void) fprintf(stderr, INVALID_SUBTREE, full_path);
                *err_code = WARNING_EXIT;
        }

        /*
         * Iterate through all the dirnames which match the pattern and
         * add them to to global list of subtrees which must be examined.
         */
        while (current_level != NULL) {
                /*
                 * Sanity check for 'bart create', make sure the subtree
                 * points to a valid object.
                 */
                ret = lstat64(current_level->dirname, &statb);
                if (ret < 0) {
                        (void) fprintf(stderr, INVALID_SUBTREE,
                            current_level->dirname);
                        current_level = current_level->next;
                        *err_code = WARNING_EXIT;
                        continue;
                }

                if (begin_rule == NULL) {
                        begin_rule =
                            add_single_rule(current_level->dirname);
                } else
                        (void) add_single_rule(current_level->dirname);

                current_level = current_level->next;
        }

        /*
         * Free up the memory and return a ptr to the first entry in the
         * subtree block.  This is necessary for the parser, which may need
         * to add modifier strings to all the elements in this block.
         */
        dirs_cleanup(tmp_ptr);

        return (begin_rule);
}


/*
 * Add a single entry to the linked list of rules to be read.  Does not do
 * the wildcard expansion of 'add_subtree_rule', so is much simpler.
 */
static struct rule *
add_single_rule(char *path)
{

        /*
         * If the rules list does NOT exist, then create it.
         * If the rules list does exist, then traverse the next element.
         */
        if (first_rule == NULL) {
                first_rule = gen_rulestruct();
                current_rule = first_rule;
        } else {
                current_rule->next = gen_rulestruct();
                current_rule->next->prev = current_rule;
                current_rule = current_rule->next;
        }

        /* Setup the rule struct, handle relocatable roots, i.e. '-R' option */
        (void) strlcpy(current_rule->subtree, path,
            sizeof (current_rule->subtree));

        return (current_rule);
}

/*
 * Code stolen from filesync utility, used by read_rules() to read in the
 * rulesfile.
 */
static char *
lex(FILE *file)
{
        char c, delim;
        char *p;
        char *s;
        static char *savep;
        static char namebuf[ BUF_SIZE ];
        static char inbuf[ BUF_SIZE ];

        if (file) {                     /* read a new line              */
                p = inbuf + sizeof (inbuf);

                s = inbuf;
                /* read the next input line, with all continuations     */
                while (savep = fgets(s, p - s, file)) {
                        lex_linenum++;

                        /* go find the last character of the input line */
                        while (*s && s[1])
                                s++;
                        if (*s == '\n')
                                s--;

                        /* see whether or not we need a continuation    */
                        if (s < inbuf || *s != '\\')
                                break;

                        continue;
                }

                if (savep == NULL)
                        return (0);

                s = inbuf;
        } else {                        /* continue with old line       */
                if (savep == NULL)
                        return (0);
                s = savep;
        }
        savep = NULL;

        /* skip over leading white space        */
        while (isspace(*s))
                s++;
        if (*s == 0)
                return (0);

        /* see if this is a quoted string       */
        c = *s;
        if (c == '\'' || c == '"') {
                delim = c;
                s++;
        } else
                delim = 0;

        /* copy the token into the buffer       */
        for (p = namebuf; (c = *s) != 0; s++) {
                /* literal escape               */
                if (c == '\\') {
                        s++;
                        *p++ = *s;
                        continue;
                }

                /* closing delimiter            */
                if (c == delim) {
                        s++;
                        break;
                }

                /* delimiting white space       */
                if (delim == 0 && isspace(c))
                        break;

                /* ordinary characters          */
                *p++ = *s;
        }


        /* remember where we left off           */
        savep = *s ? s : 0;

        /* null terminate and return the buffer */
        *p = 0;
        return (namebuf);
}

/*
 * Iterate through the dir strcutures and free memory.
 */
static void
dirs_cleanup(struct dir_component *dir)
{
        struct  dir_component   *next;

        while (dir != NULL) {
                next = dir->next;
                free(dir);
                dir = next;
        }
}

/*
 * Create and initialize a new dir structure.  Used by add_subtree_rule() when
 * doing expansion of directory names caused by wildcards.
 */
static void
add_dir(struct dir_component **dir, char *dirname)
{
        struct  dir_component   *new, *next_dir;

        new = gen_dir_component();
        if (dirname != NULL)
                (void) strlcpy(new->dirname, dirname, sizeof (new->dirname));

        if (*dir == NULL)
                *dir = new;
        else {
                next_dir = *dir;
                while (next_dir->next != NULL)
                        next_dir = next_dir->next;

                next_dir->next = new;
        }
}

/*
 * Traverse the linked list of rules in a REVERSE order.
 */
static struct rule *
get_last_entry(boolean_t reset)
{
        static struct rule      *curr_root = NULL;

        if (reset) {

                curr_root = first_rule;

                /* RESET: set cur_root to the end of the list */
                while (curr_root != NULL)
                        if (curr_root->next == NULL)
                                break;
                        else
                                curr_root = curr_root->next;
        } else
                curr_root = (curr_root->prev);

        return (curr_root);
}

/*
 * Traverse the first entry, used by 'bart create' to iterate through
 * subtrees or individual filenames.
 */
struct rule *
get_first_subtree()
{
        return (first_rule);
}

/*
 * Traverse the next entry, used by 'bart create' to iterate through
 * subtrees or individual filenames.
 */
struct rule *
get_next_subtree(struct rule *entry)
{
        return (entry->next);
}

char *
safe_strdup(char *s)
{
        char *ret;
        size_t len;

        len = strlen(s) + 1;
        ret = safe_calloc(len);
        (void) strlcpy(ret, s, len);
        return (ret);
}

/*
 * Function to match a filename against the subtrees in the link list
 * of 'rule' strcutures.  Upon finding a matching rule, see if it should
 * be excluded.  Keep going until a match is found OR all rules have been
 * exhausted.
 * NOTES: Rules are parsed in reverse;
 * satisfies the spec that "Last rule wins".  Also, the default rule should
 * always match, so this function should NEVER return NULL.
 */
struct rule *
check_rules(const char *fname, char type)
{
        struct rule             *root;

        root = get_last_entry(B_TRUE);
        while (root != NULL) {
                if (match_subtree(fname, root->subtree)) {
                        if (exclude_fname(fname, type, root) == NO_EXCLUDE)
                                break;
                }
                root = get_last_entry(B_FALSE);
        }

        return (root);
}

/*
 * Function to determine if an entry in a rules file (see bart_rules(5)) applies
 * to a filename. We truncate "fname" such that it has the same number of
 * components as "rule" and let fnmatch(3C) do the rest. A "component" is one
 * part of an fname as delimited by slashes ('/'). So "/A/B/C/D" has four
 * components: "A", "B", "C" and "D".
 *
 * For example:
 *
 * 1. the rule "/home/nickiso" applies to fname "/home/nickiso/src/foo.c" so
 * should match.
 *
 * 2. the rule "/home/nickiso/temp/src" does not apply to fname
 * "/home/nickiso/foo.c" so should not match.
 */
static int
match_subtree(const char *fname, char *rule)
{
        int     match, num_rule_slash;
        char    *ptr, fname_cp[PATH_MAX];

        /* If rule has more components than fname, it cannot match. */
        if ((num_rule_slash = count_slashes(rule)) > count_slashes(fname))
                return (0);

        /* Create a copy of fname that we can truncate. */
        (void) strlcpy(fname_cp, fname, sizeof (fname_cp));

        /*
         * Truncate fname_cp such that it has the same number of components
         * as rule. If rule ends with '/', so should fname_cp. ie:
         *
         * rule         fname                   fname_cp        matches
         * ----         -----                   --------        -------
         * /home/dir*   /home/dir0/dir1/fileA   /home/dir0      yes
         * /home/dir/   /home/dir0/dir1/fileA   /home/dir0/     no
         */
        for (ptr = fname_cp; num_rule_slash > 0; num_rule_slash--, ptr++)
                ptr = strchr(ptr, '/');
        if (*(rule + strlen(rule) - 1) != '/') {
                while (*ptr != '\0') {
                        if (*ptr == '/')
                                break;
                        ptr++;
                }
        }
        *ptr = '\0';

        /* OK, now see if they match. */
        match = fnmatch(rule, fname_cp, FNM_PATHNAME);

        /* No match, return failure */
        if (match != 0)
                return (0);
        else
                return (1);
}

void
process_glob_ignores(char *ignore_list, uint_t *flags)
{
        char    *cp;
        struct attr_keyword *akp;

        if (ignore_list == NULL)
                usage();

        cp = strtok(ignore_list, ",");
        while (cp != NULL) {
                akp = attr_keylookup(cp);
                if (akp == NULL)
                        (void) fprintf(stderr, "ERROR: Invalid keyword %s\n",
                            cp);
                else
                        *flags &= ~akp->ak_flags;
                cp = strtok(NULL, ",");
        }
}