searchweb.c

Go to the documentation of this file.

/*
 * Copyright 2014 Vincent Sanders <vince@netsurf-browser.org>
 *
 * This file is part of NetSurf, http://www.netsurf-browser.org/
 *
 * NetSurf 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; version 2 of the License.
 *
 * NetSurf 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
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
/**
 * \file
 * \brief core web search facilities implementation.
 */
 
#include <stdlib.h>
#include <string.h>
 
#include "utils/utils.h"
#include "utils/log.h"
#include "utils/url.h"
#include "utils/nsoption.h"
#include "netsurf/content.h"
#include "content/hlcache.h"
 
#include "desktop/searchweb.h"
#include "desktop/gui_internal.h"
 
struct search_provider {
        char *name; /**< readable name such as 'google', 'yahoo', etc */
        char *hostname; /**< host address such as www.google.com */
        char *searchstring; /** < such as "www.google.com?search=%s" */
        char *ico; /** < location of domain's favicon */
        hlcache_handle *ico_handle;
};
 
static struct search_web_ctx_s {
        struct search_provider *providers; /* web search providers */
        size_t providers_count; /* number of providers */
 
        size_t current; /* current provider */
 
        hlcache_handle *default_ico_handle;
 
} search_web_ctx;
 
 
static const char *default_providers = "DuckDuckGo|www.duckduckgo.com|https://www.duckduckgo.com/html/?q=%s|https://www.duckduckgo.com/favicon.ico|\n";
 
static const char *default_search_icon_url = "resource:icons/search.png";
 
 
/**
 * Read providers file.
 *
 * Allocates storage of sufficient size for the providers file and
 * reads the entire file in.
 *
 * \param fname The filename to read.
 * \param providers_out A pointer to place the result buffer in.
 * \param providers_size_out Size of buffer.
 * \return NSERROR_OK and providers_out updated or appropriate error code.
 */
static nserror
read_providers(const char *fname,
               char **providers_out,
               size_t *providers_size_out)
{
        FILE *providersf;
        long ftellsize;
        size_t fsize;
        char *providersd;
 
        if (fname == NULL) {
                return NSERROR_BAD_PARAMETER;
        }
 
        providersf = fopen(fname, "r");
        if (providersf == NULL) {
                return NSERROR_NOT_FOUND;
        }
 
        if (fseek(providersf, 0, SEEK_END) != 0) {
                fclose(providersf);
                return NSERROR_INVALID;
        }
 
        ftellsize = ftell(providersf);
        if (ftellsize < 0) {
                fclose(providersf);
                return NSERROR_INVALID;
        }
        fsize = ftellsize;
 
        if (fseek(providersf, 0, SEEK_SET) != 0) {
                fclose(providersf);
                return NSERROR_INVALID;
        }
 
        providersd = malloc(fsize + 1);
        if (providersd == NULL) {
                fclose(providersf);
                return NSERROR_NOMEM;
        }
 
        if (fread(providersd, 1, fsize, providersf) != fsize) {
                fclose(providersf);
                free(providersd);
                return NSERROR_BAD_SIZE;
        }
        providersd[fsize] = 0; /* ensure null terminated */
 
        fclose(providersf);
 
        *providers_out = providersd;
        *providers_size_out = fsize;
 
        return NSERROR_OK;
}
 
/**
 * parse search providers from a memory block.
 *
 * \param providersd The provider info data.
 * \param providers_size The size of the provider data.
 * \param providers_out The resulting provider array.
 * \param providers_count The number of providers in the output array.
 * \return NSERROR_OK on success or error code on failure.
 */
static nserror
parse_providers(char *providersd,
                size_t providers_size,
                struct search_provider **providers_out,
                size_t *providers_count)
{
        size_t pcount = 0; /* number of providers */
        size_t pidx;
        char *nl = providersd;
        struct search_provider *providers;
 
        /* count newlines */
        while (nl != NULL) {
                nl = strchr(nl, '\n');
                if (nl != NULL) {
                        nl++;
                        pcount+=1;
                }
        }
 
        if (pcount == 0) {
                return NSERROR_INVALID;
        }
 
        providers = malloc(pcount * sizeof(*providers));
        if (providers == NULL) {
                return NSERROR_NOMEM;
        }
 
        nl = providersd;
        for (pidx = 0; pidx < pcount; pidx++) {
                providers[pidx].name = nl;
                nl = strchr(nl, '|');
                if (nl == NULL) {
                        free(providers);
                        return NSERROR_INVALID;
                }
                *nl = 0;
                nl++;
 
                providers[pidx].hostname = nl;
                nl = strchr(nl, '|');
                if (nl == NULL) {
                        free(providers);
                        return NSERROR_INVALID;
                }
                *nl = 0;
                nl++;
 
                providers[pidx].searchstring = nl;
                nl = strchr(nl, '|');
                if (nl == NULL) {
                        free(providers);
                        return NSERROR_INVALID;
                }
                *nl = 0;
                nl++;
 
                providers[pidx].ico = nl;
                nl = strchr(nl, '|');
                if (nl == NULL) {
                        free(providers);
                        return NSERROR_INVALID;
                }
                *nl = 0;
                nl++;
 
                /* skip newline */
                nl = strchr(nl, '\n');
                if (nl == NULL) {
                        free(providers);
                        return NSERROR_INVALID;
                }
                nl++;
 
                providers[pidx].ico_handle = NULL;
        }
 
        *providers_out = providers;
        *providers_count = pcount;
 
        return NSERROR_OK;
}
 
/**
 * create a url for a search provider and a term
 *
 * \param provider The provider to use.
 * \param term The term being searched for.
 * \param url_out The resulting url.
 * \return NSERROR_OK on success or appropriate error code.
 */
static nserror
make_search_nsurl(struct search_provider *provider,
                const char *term,
                nsurl **url_out)
{
        nserror ret;
        nsurl *url;
        char *eterm; /* escaped term */
        char *searchstr; /* the providers search string */
        char *urlstr; /* the escaped term substituted into the provider */
        char *urlstro;
        size_t urlstr_len;
 
        /* escape the search term and join it to the search url */
        ret = url_escape(term, true, NULL, &eterm);
        if (ret != NSERROR_OK) {
                return ret;
        }
 
        searchstr = provider->searchstring;
 
        urlstr_len = strlen(searchstr) + strlen(eterm)  + 1;
        urlstro = urlstr = malloc(urlstr_len);
        if (urlstr == NULL) {
                free(eterm);
                return NSERROR_NOMEM;
        }
 
        /* composite search url */
        for ( ; *searchstr != 0; searchstr++, urlstro++) {
                *urlstro = *searchstr;
                if ((*searchstr == '%') && (searchstr[1] == 's')) {
                        searchstr++; /* skip % */
                        memcpy(urlstro, eterm, strlen(eterm));
                        urlstro += strlen(eterm) - 1;
                }
        }
        free(eterm);
        *urlstro = '\0'; /* ensure string is NULL-terminated */
 
        ret = nsurl_create(urlstr, &url);
        free(urlstr);
        if (ret != NSERROR_OK) {
                return ret;
        }
 
        *url_out = url;
        return NSERROR_OK;
}
 
/**
 * callback for hlcache icon fetch events.
 */
static nserror
search_web_ico_callback(hlcache_handle *ico,
                        const hlcache_event *event,
                        void *pw)
{
        struct search_provider *provider = pw;
 
        switch (event->type) {
 
        case CONTENT_MSG_DONE:
                NSLOG(netsurf, INFO, "icon '%s' retrieved",
                      nsurl_access(hlcache_handle_get_url(ico)));
                guit->search_web->provider_update(provider->name,
                                                  content_get_bitmap(ico));
                break;
 
        case CONTENT_MSG_ERROR:
                NSLOG(netsurf, INFO, "icon %s error: %s",
                      nsurl_access(hlcache_handle_get_url(ico)),
                      event->data.errordata.errormsg);
 
                hlcache_handle_release(ico);
                /* clear reference to released handle */
                provider->ico_handle = NULL;
                break;
 
        default:
                break;
        }
 
        return NSERROR_OK;
}
 
/* exported interface documented in desktop/searchweb.h */
nserror
search_web_omni(const char *term,
                enum search_web_omni_flags flags,
                struct nsurl **url_out)
{
        nserror ret;
        nsurl *url;
        char *eterm; /* encoded/altered search term */
 
        if ((flags & SEARCH_WEB_OMNI_SEARCHONLY) == 0) {
 
                /* first check to see if the term is a url */
                ret = nsurl_create(term, &url);
                if (ret == NSERROR_OK) {
                        *url_out = url;
                        return NSERROR_OK;
                }
 
                /* try with adding default scheme */
                eterm = malloc(strlen(term) + SLEN("https://") + 1);
                if (eterm == NULL) {
                        return NSERROR_NOMEM;
                }
                sprintf(eterm, "https://%s", term);
                ret = nsurl_create(eterm, &url);
                free(eterm);
                if (ret == NSERROR_OK) {
                        *url_out = url;
                        return NSERROR_OK;
                }
 
                /* do not pass to search if user has disabled the option */
                if (nsoption_bool(search_url_bar) == false) {
                        return NSERROR_BAD_URL;
                }
        }
 
        /* ensure providers are initialised */
        if (search_web_ctx.providers == NULL) {
                ret = search_web_init(NULL);
                if (ret != NSERROR_OK) {
                        return ret;
                }
        }
        if (search_web_ctx.providers == NULL) {
                return NSERROR_INIT_FAILED;
        }
 
        /* turn search into a nsurl */
        ret = make_search_nsurl(&search_web_ctx.providers[search_web_ctx.current], term, &url);
        if (ret != NSERROR_OK) {
                return ret;
        }
 
        *url_out = url;
        return NSERROR_OK;
}
 
/* exported interface documented in desktop/searchweb.h */
nserror search_web_get_provider_bitmap(struct bitmap **bitmap_out)
{
        struct search_provider *provider;
        struct bitmap *ico_bitmap = NULL;
 
        /* must be initialised */
        if (search_web_ctx.providers == NULL) {
                return NSERROR_INIT_FAILED;
        }
 
        provider = &search_web_ctx.providers[search_web_ctx.current];
 
        /* set the icon now (if we can) at least to the default */
        if (provider->ico_handle != NULL) {
                ico_bitmap = content_get_bitmap(provider->ico_handle);
        }
        if ((ico_bitmap == NULL) &&
            (search_web_ctx.default_ico_handle != NULL)) {
                ico_bitmap = content_get_bitmap(search_web_ctx.default_ico_handle);
        }
 
        *bitmap_out = ico_bitmap;
        return NSERROR_OK;
}
 
 
/* exported interface documented in desktop/searchweb.h */
nserror search_web_select_provider(const char *selection)
{
        struct search_provider *provider;
        struct bitmap *ico_bitmap = NULL;
        size_t pidx;
 
        /* must be initialised */
        if (search_web_ctx.providers == NULL) {
                return NSERROR_INIT_FAILED;
        }
 
        /* negative value just selects whatevers current */
        if (selection != NULL) {
                for (pidx=0; pidx < search_web_ctx.providers_count;pidx++) {
                        if (strcmp(search_web_ctx.providers[pidx].name, selection)==0) {
                                search_web_ctx.current = pidx;
                                break;
                        }
                }
                if (pidx == search_web_ctx.providers_count) {
                        /* selected provider not found */
                        search_web_ctx.current = 0;
                }
        }
 
        provider = &search_web_ctx.providers[search_web_ctx.current];
 
        /* set the icon now (if we can) at least to the default */
        if (provider->ico_handle != NULL) {
                ico_bitmap = content_get_bitmap(provider->ico_handle);
        }
        if ((ico_bitmap == NULL) &&
            (search_web_ctx.default_ico_handle != NULL)) {
                ico_bitmap = content_get_bitmap(search_web_ctx.default_ico_handle);
        }
 
        /* signal the frontend with the provider change. Bitmap may
         * be NULL at this point.
         */
        guit->search_web->provider_update(provider->name, ico_bitmap);
 
        /* if the providers icon has not been retrieved get it now */
        if (provider->ico_handle == NULL) {
                nsurl *icon_nsurl;
                nserror ret;
 
                /* create search icon url */
                ret = nsurl_create(provider->ico, &icon_nsurl);
                if (ret != NSERROR_OK) {
                        return ret;
                }
 
                ret = hlcache_handle_retrieve(icon_nsurl, 0, NULL, NULL,
                                              search_web_ico_callback,
                                              provider,
                                              NULL, CONTENT_IMAGE,
                                              &provider->ico_handle);
                nsurl_unref(icon_nsurl);
                if (ret != NSERROR_OK) {
                        provider->ico_handle = NULL;
                        return ret;
                }
        }
 
        return NSERROR_OK;
}
 
/**
 * callback for hlcache icon fetch events.
 */
static nserror
default_ico_callback(hlcache_handle *ico,
                     const hlcache_event *event,
                     void *pw)
{
        struct search_web_ctx_s *ctx = pw;
 
        switch (event->type) {
 
        case CONTENT_MSG_DONE:
                NSLOG(netsurf, INFO, "default icon '%s' retrieved",
                      nsurl_access(hlcache_handle_get_url(ico)));
 
                /* only set to default icon if providers icon has no handle */
                if (ctx->providers[search_web_ctx.current].ico_handle == NULL) {
                        guit->search_web->provider_update(
                                ctx->providers[search_web_ctx.current].name,
                                content_get_bitmap(ico));
                }
                break;
 
        case CONTENT_MSG_ERROR:
                NSLOG(netsurf, INFO, "icon %s error: %s",
                      nsurl_access(hlcache_handle_get_url(ico)),
                      event->data.errordata.errormsg);
 
                hlcache_handle_release(ico);
                /* clear reference to released handle */
                ctx->default_ico_handle = NULL;
                break;
 
        default:
                break;
        }
 
        return NSERROR_OK;
}
 
/* exported interface documented in desktop/searchweb.h */
ssize_t search_web_iterate_providers(ssize_t iter, const char **name)
{
        if (iter < 0) {
                iter=0;
        } else {
                iter++;
        }
 
        if ((size_t)iter >= search_web_ctx.providers_count) {
                iter = -1;
        } else {
                *name = search_web_ctx.providers[iter].name;
        }
 
        return iter;
}
 
 
/* exported interface documented in desktop/searchweb.h */
nserror search_web_init(const char *provider_fname)
{
        nserror ret;
        char *providers;
        size_t providers_size;
        nsurl *icon_nsurl;
 
        /* create search icon url */
        ret = nsurl_create(default_search_icon_url, &icon_nsurl);
        if (ret != NSERROR_OK) {
                return ret;
        }
 
        /* get a list of providers */
        ret = read_providers(provider_fname, &providers, &providers_size);
        if (ret != NSERROR_OK) {
                providers = strdup(default_providers);
                if (providers == NULL) {
                        return NSERROR_NOMEM;
                }
                providers_size = strlen(providers);
        }
 
        /* parse list of providers */
        ret = parse_providers(providers,
                              providers_size,
                              &search_web_ctx.providers,
                              &search_web_ctx.providers_count);
        if (ret != NSERROR_OK) {
                free(providers);
                return ret;
        }
 
        /* get default search icon */
        ret = hlcache_handle_retrieve(icon_nsurl,
                                      0,
                                      NULL,
                                      NULL,
                                      default_ico_callback,
                                      &search_web_ctx,
                                      NULL,
                                      CONTENT_IMAGE,
                                      &search_web_ctx.default_ico_handle);
        nsurl_unref(icon_nsurl);
        if (ret != NSERROR_OK) {
                search_web_ctx.default_ico_handle = NULL;
                free(search_web_ctx.providers);
                search_web_ctx.providers = NULL;
                free(providers);
                return ret;
        }
 
 
        return NSERROR_OK;
}
 
/* exported interface documented in desktop/searchweb.h */
nserror search_web_finalise(void)
{
        size_t pidx;
 
        /* must be initialised */
        if (search_web_ctx.providers == NULL) {
                return NSERROR_INIT_FAILED;
        }
 
        if (search_web_ctx.default_ico_handle != NULL) {
                hlcache_handle_release(search_web_ctx.default_ico_handle);
        }
        for (pidx = 0; pidx < search_web_ctx.providers_count; pidx++) {
                if (search_web_ctx.providers[pidx].ico_handle != NULL) {
                        hlcache_handle_release(search_web_ctx.providers[pidx].ico_handle);
                }
        }
 
        /* All the search provider data is held in a single block for
         * efficiency.
         */
        free(search_web_ctx.providers[0].name);
 
        free(search_web_ctx.providers);
        search_web_ctx.providers = NULL;
 
        return NSERROR_OK;
}