lnav/src/textview_curses.hh

/**
 * Copyright (c) 2007-2012, Timothy Stack
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 * * 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.
 * * Neither the name of Timothy Stack 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.
 *
 * @file textview_curses.hh
 */

#ifndef __textview_curses_hh
#define __textview_curses_hh

#include <vector>

#include "grep_proc.hh"
#include "bookmarks.hh"
#include "listview_curses.hh"

class textview_curses;

/**
 * Source for the text to be shown in a textview_curses view.
 */
class text_sub_source {
public:
    virtual ~text_sub_source() { };

    virtual void toggle_scrub(void) { };

    /**
     * @return The total number of lines available from the source.
     */
    virtual size_t text_line_count() = 0;

    /**
     * Get the value for a line.
     *
     * @param tc The textview_curses object that is delegating control.
     * @param line The line number to retrieve.
     * @param value_out The string object that should be set to the line
     *   contents.
     * @param raw Indicates that the raw contents of the line should be returned
     *   without any post processing.
     */
    virtual void text_value_for_line(textview_curses &tc,
                                     int line,
                                     std::string &value_out,
                                     bool raw = false) = 0;

    /**
     * Inform the source that the given line has been marked/unmarked.  This
     * callback function can be used to translate between between visible line
     * numbers and content line numbers.  For example, when viewing a log file
     * with filters being applied, we want the bookmarked lines to be stable
     * across changes in the filters.
     *
     * @param bm    The type of bookmark.
     * @param line  The line that has been marked/unmarked.
     * @param added True if the line was bookmarked and false if it was
     *   unmarked.
     */
    virtual void text_mark(bookmark_type_t *bm, int line, bool added) {};

    /**
     * Clear the bookmarks for a particular type in the text source.
     *
     * @param bm The type of bookmarks to clear.
     */
    virtual void text_clear_marks(bookmark_type_t *bm) {};

    /**
     * Get the attributes for a line of text.
     *
     * @param tc The textview_curses object that is delegating control.
     * @param line The line number to retrieve.
     * @param value_out A string_attrs_t object that should be updated with the
     *   attributes for the line.
     */
    virtual void text_attrs_for_line(textview_curses &tc,
                                     int line,
                                     string_attrs_t &value_out) {};

    /**
     * Update the bookmarks used by the text view based on the bookmarks
     * maintained by the text source.
     *
     * @param bm The bookmarks data structure used by the text view.
     */
    virtual void text_update_marks(vis_bookmarks &bm) { };
};

/**
 * The textview_curses class adds user bookmarks and searching to the standard
 * list view interface.
 */
class textview_curses
    : public listview_curses,
      public list_data_source,
      public grep_proc_source,
      public grep_proc_sink {
public:

    typedef view_action<textview_curses> action;

    static bookmark_type_t BM_USER;
    static bookmark_type_t BM_SEARCH;

    struct highlighter {
        highlighter()
            : h_code(NULL),
              h_multiple(false) { };
        highlighter(pcre *code,
                    bool multiple = false,
                    view_colors::role_t role = view_colors::VCR_NONE)
            : h_code(code),
              h_multiple(multiple)
        {
            const char *errptr;

            if (!multiple) {
                if (role == view_colors::VCR_NONE) {
                    this->h_roles.
                    push_back(view_colors::singleton().next_highlight());
                }
                else {
                    this->h_roles.push_back(role);
                }
            }
            this->h_code_extra = pcre_study(this->h_code, 0, &errptr);
            if (!this->h_code_extra && errptr) {
                fprintf(stderr, "pcre_study error: %s\n", errptr);
            }
            if (this->h_code_extra != NULL) {
                pcre_extra *extra = this->h_code_extra;

                extra->flags |= (PCRE_EXTRA_MATCH_LIMIT |
                                 PCRE_EXTRA_MATCH_LIMIT_RECURSION);
                extra->match_limit           = 10000;
                extra->match_limit_recursion = 500;
            }
        };

        view_colors::role_t              get_role(unsigned int index)
        {
            view_colors &       vc = view_colors::singleton();
            view_colors::role_t retval;

            if (this->h_multiple) {
                while (index >= this->h_roles.size()) {
                    this->h_roles.push_back(vc.next_highlight());
                }
                retval = this->h_roles[index];
            }
            else {
                retval = this->h_roles[0];
            }

            return retval;
        };

        int                              get_attrs(int index)
        {
            return view_colors::singleton().
                   attrs_for_role(this->get_role(index));
        };

        pcre *                           h_code;
        pcre_extra *                     h_code_extra;
        bool                             h_multiple;
        std::vector<view_colors::role_t> h_roles;
    };

    textview_curses();
    virtual ~textview_curses();

    vis_bookmarks &get_bookmarks(void) { return this->tc_bookmarks; };

    void set_sub_source(text_sub_source *src)
    {
        this->tc_sub_source = src;
        this->reload_data();
    };
    text_sub_source *get_sub_source(void) { return this->tc_sub_source; };

    void horiz_shift(vis_line_t start, vis_line_t end,
                     int off_start,
                     std::string highlight_name,
                     std::pair<int, int> &range_out)
    {
        highlighter &hl       = this->tc_highlights[highlight_name];
        int          prev_hit = -1, next_hit = INT_MAX;
        std::string  str;

        for (; start < end; ++start) {
            int off;

            this->tc_sub_source->text_value_for_line(*this, start, str);

            for (off = 0; off < (int)str.size(); ) {
                int rc, matches[60];

                rc = pcre_exec(hl.h_code,
                               hl.h_code_extra,
                               str.c_str(),
                               str.size(),
                               off,
                               0,
                               matches,
                               60);
                if (rc > 0) {
                    struct line_range lr;

                    if (rc == 2) {
                        lr.lr_start = matches[2];
                        lr.lr_end   = matches[3];
                    }
                    else {
                        lr.lr_start = matches[0];
                        lr.lr_end   = matches[1];
                    }

                    if (lr.lr_start < off_start) {
                        prev_hit = std::max(prev_hit, lr.lr_start);
                    }
                    else if (lr.lr_start > off_start) {
                        next_hit = std::min(next_hit, lr.lr_start);
                    }
                    if (lr.lr_end > lr.lr_start) {
                        off = matches[1];
                    }
                    else {
                        off += 1;
                    }
                }
                else {
                    off = str.size();
                }
            }
        }

        range_out = std::make_pair(prev_hit, next_hit);
    };

    void set_search_action(action sa) { this->tc_search_action = sa; };

    template<class _Receiver>
    void set_search_action(action::mem_functor_t<_Receiver> *mf)
    {
        this->tc_search_action = action(mf);
    };

    void grep_end_batch(grep_proc &gp)
    {
        if (this->tc_follow_search &&
            !this->tc_bookmarks[&BM_SEARCH].empty()) {
            vis_line_t first_hit;

            first_hit = this->tc_bookmarks[&BM_SEARCH].
                        next(vis_line_t(this->get_top() - 1));
            if (first_hit != -1) {
                if (first_hit > 0) {
                    --first_hit;
                }
                this->set_top(first_hit);
            }
        }
        this->tc_search_action.invoke(this);
    };
    void grep_end(grep_proc &gp);

    size_t listview_rows(const listview_curses &lv)
    {
        return this->tc_sub_source == NULL ? 0 :
               this->tc_sub_source->text_line_count();
    };

    void listview_value_for_row(const listview_curses &lv,
                                vis_line_t line,
                                attr_line_t &value_out);

    bool grep_value_for_line(int line, std::string &value_out)
    {
        bool retval = false;

        if (line < (int)this->tc_sub_source->text_line_count()) {
            this->tc_sub_source->text_value_for_line(*this,
                                                     line,
                                                     value_out,
                                                     true);
            retval = true;
        }

        return retval;
    };

    void grep_begin(grep_proc &gp);
    void grep_match(grep_proc &gp,
                    grep_line_t line,
                    int start,
                    int end);

    bool is_searching(void) { return this->tc_searching; };

    void set_follow_search(bool fs) { this->tc_follow_search = fs; };

    size_t get_match_count(void)
    {
        return this->tc_bookmarks[&BM_SEARCH].size();
    };

    void match_reset()
    {
        this->tc_bookmarks[&BM_SEARCH].clear();
        if (this->tc_sub_source != NULL) {
            this->tc_sub_source->text_clear_marks(&BM_SEARCH);
        }
    };

    typedef std::map<std::string, highlighter> highlight_map_t;

    highlight_map_t &get_highlights() { return this->tc_highlights; };

    void reload_data(void);

protected:
    text_sub_source *tc_sub_source;

    vis_bookmarks tc_bookmarks;

    vis_line_t tc_lview_top;
    int        tc_lview_left;

    bool   tc_searching;
    bool   tc_follow_search;
    action tc_search_action;

    highlight_map_t           tc_highlights;
    highlight_map_t::iterator tc_current_highlight;
};
#endif