source: help.c @ 8fdeaa5

/********************************************************************\
  * BitlBee -- An IRC to other IM-networks gateway                     *
  *                                                                    *
  * Copyright 2002-2010 Wilmer van der Gaast and others                *
  \********************************************************************/

/* Help file control                                                    */

/*
  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License with
  the Debian GNU/Linux distribution in /usr/share/common-licenses/GPL;
  if not, write to the Free Software Foundation, Inc., 51 Franklin St.,
  Fifth Floor, Boston, MA  02110-1301  USA
*/

#define BITLBEE_CORE
#include "bitlbee.h"
#include "help.h"
#undef read
#undef write

#define BUFSIZE 2048

help_t *help_init(help_t **help, const char *helpfile)
{
        int i, buflen = 0;
        help_t *h;
        char *s, *t;
        time_t mtime;
        struct stat stat[1];

        *help = h = g_new0(help_t, 1);

        h->fd = open(helpfile, O_RDONLY);

        if (h->fd == -1) {
                g_free(h);
                return(*help = NULL);
        }

        if (fstat(h->fd, stat) != 0) {
                g_free(h);
                return(*help = NULL);
        }
        mtime = stat->st_mtime;

        s = g_new(char, BUFSIZE + 1);
        s[BUFSIZE] = 0;

        while (((i = read(h->fd, s + buflen, BUFSIZE - buflen)) > 0) ||
               (i == 0 && strstr(s, "\n%\n"))) {
                buflen += i;
                memset(s + buflen, 0, BUFSIZE - buflen);
                if (!(t = strstr(s, "\n%\n")) || s[0] != '?') {
                        /* FIXME: Clean up */
                        help_free(help);
                        g_free(s);
                        return NULL;
                }
                i = strchr(s, '\n') - s;

                if (h->title) {
                        h = h->next = g_new0(help_t, 1);
                }
                h->title = g_new(char, i);

                strncpy(h->title, s + 1, i - 1);
                h->title[i - 1] = 0;
                h->fd = (*help)->fd;
                h->offset.file_offset = lseek(h->fd, 0, SEEK_CUR) - buflen + i + 1;
                h->length = t - s - i - 1;
                h->mtime = mtime;

                buflen -= (t + 3 - s);
                t = g_strdup(t + 3);
                g_free(s);
                s = g_renew(char, t, BUFSIZE + 1);
                s[BUFSIZE] = 0;
        }

        g_free(s);

        return(*help);
}

void help_free(help_t **help)
{
        help_t *h, *oh;
        int last_fd = -1; /* Weak de-dupe */

        if (help == NULL || *help == NULL) {
                return;
        }

        h = *help;
        while (h) {
                if (h->fd != last_fd) {
                        close(h->fd);
                        last_fd = h->fd;
                }
                g_free(h->title);
                h = (oh = h)->next;
                g_free(oh);
        }

        *help = NULL;
}

char *help_get(help_t **help, char *title)
{
        time_t mtime;
        struct stat stat[1];
        help_t *h;

        for (h = *help; h; h = h->next) {
                if (h->title != NULL && g_strcasecmp(h->title, title) == 0) {
                        break;
                }
        }
        if (h && h->length > 0) {
                char *s = g_new(char, h->length + 1);

                s[h->length] = 0;
                if (h->fd >= 0) {
                        if (fstat(h->fd, stat) != 0) {
                                g_free(s);
                                return NULL;
                        }
                        mtime = stat->st_mtime;

                        if (mtime > h->mtime) {
                                g_free(s);
                                return NULL;
                        }

                        if (lseek(h->fd, h->offset.file_offset, SEEK_SET) == -1 ||
                            read(h->fd, s, h->length) != h->length) {
                                g_free(s);
                                return NULL;
                        }
                } else {
                        strncpy(s, h->offset.mem_offset, h->length);
                }
                return s;
        }

        return NULL;
}

int help_add_mem(help_t **help, const char *title, const char *content)
{
        help_t *h, *l = NULL;

        for (h = *help; h; h = h->next) {
                if (g_strcasecmp(h->title, title) == 0) {
                        return 0;
                }

                l = h;
        }

        if (l) {
                h = l->next = g_new0(struct help, 1);
        } else {
                *help = h = g_new0(struct help, 1);
        }
        h->fd = -1;
        h->title = g_strdup(title);
        h->length = strlen(content);
        h->offset.mem_offset = g_strdup(content);

        return 1;
}

char *help_get_whatsnew(help_t **help, int old)
{
        GString *ret = NULL;
        help_t *h;
        int v;

        for (h = *help; h; h = h->next) {
                if (h->title != NULL && strncmp(h->title, "whatsnew", 8) == 0 &&
                    sscanf(h->title + 8, "%x", &v) == 1 && v > old) {
                        char *s = help_get(&h, h->title);
                        if (ret == NULL) {
                                ret = g_string_new(s);
                        } else {
                                g_string_append_printf(ret, "\n\n%s", s);
                        }
                        g_free(s);
                }
        }

        return ret ? g_string_free(ret, FALSE) : NULL;
}