fetch_rsrc.cpp

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/*
 * Copyright 2008 François Revol <mmu_man@users.sourceforge.net>
 * Copyright 2008 Rob Kendrick <rjek@netsurf-browser.org>
 *
 * This file is part of NetSurf.
 *
 * 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/>.
 */
 
/* rsrc: URL handling. */
 
#define __STDBOOL_H__   1
#include <stdlib.h>
#include <assert.h>
#include <errno.h>
#include <stdbool.h>
#include <string.h>
#include <strings.h>
#include <time.h>
#include <sys/select.h>
#include <sys/stat.h>
#include <sys/utsname.h>
#include <image.h>
#include <Resources.h>
#include <String.h>
#include <libwapcaplet/libwapcaplet.h>
 
extern "C" {
#include "utils/config.h"
#include "utils/nsoption.h"
#include "utils/log.h"
#include "utils/messages.h"
#include "utils/utils.h"
#include "utils/ring.h"
#include "content/fetch.h"
#include "content/fetchers.h"
}
 
#include "beos/fetch_rsrc.h"
#include "beos/filetype.h"
#include "beos/gui.h"
 
 
struct fetch_rsrc_context {
        struct fetch *parent_fetch;
        char *name;
        char *url;
        char *mimetype;
        char *data;
        size_t datalen;
 
        bool aborted;
        bool locked;
        
        struct fetch_rsrc_context *r_next, *r_prev;
};
 
static struct fetch_rsrc_context *ring = NULL;
 
BResources *gAppResources = NULL;
 
static bool fetch_rsrc_initialise(lwc_string *scheme)
{
        NSLOG(netsurf, INFO, "fetch_rsrc_initialise called for %s",
              lwc_string_data(scheme));
        return true;
}
 
static void fetch_rsrc_finalise(lwc_string *scheme)
{
        NSLOG(netsurf, INFO, "fetch_rsrc_finalise called for %s",
              lwc_string_data(scheme));
}
 
static bool fetch_rsrc_can_fetch(const nsurl *url)
{
        return true;
}
 
static void *fetch_rsrc_setup(struct fetch *parent_fetch, nsurl *url,
                 bool only_2xx, bool downgrade_tls, const char *post_urlenc,
                 const struct fetch_multipart_data *post_multipart,
                 const char **headers)
{
        struct fetch_rsrc_context *ctx;
        ctx = (struct fetch_rsrc_context *)calloc(1, sizeof(*ctx));
        
        if (ctx == NULL)
                return NULL;
                
        ctx->parent_fetch = parent_fetch;
        /* TODO: keep as nsurl to avoid copy */
        ctx->url = (char *)malloc(nsurl_length(url) + 1);
        
        if (ctx->url == NULL) {
                free(ctx);
                return NULL;
        }
        memcpy(ctx->url, nsurl_access(url), nsurl_length(url) + 1);
 
        RING_INSERT(ring, ctx);
        
        return ctx;
}
 
static bool fetch_rsrc_start(void *ctx)
{
        return true;
}
 
static void fetch_rsrc_free(void *ctx)
{
        struct fetch_rsrc_context *c = (struct fetch_rsrc_context *)ctx;
 
        free(c->name);
        free(c->url);
        free(c->data);
        free(c->mimetype);
        RING_REMOVE(ring, c);
        free(ctx);
}
 
static void fetch_rsrc_abort(void *ctx)
{
        struct fetch_rsrc_context *c = (struct fetch_rsrc_context *)ctx;
 
        /* To avoid the poll loop having to deal with the fetch context
         * disappearing from under it, we simply flag the abort here. 
         * The poll loop itself will perform the appropriate cleanup.
         */
        c->aborted = true;
}
 
static void fetch_rsrc_send_callback(const fetch_msg *msg, 
                struct fetch_rsrc_context *c)
{
        c->locked = true;
        fetch_send_callback(msg, c->parent_fetch);
        c->locked = false;
}
 
static bool fetch_rsrc_process(struct fetch_rsrc_context *c)
{
        fetch_msg msg;
        char *params;
        //char *at = NULL;
        char *slash;
        //char *comma = NULL;
        //char *unescaped;
        uint32 type = 'data'; // default for embeded files
        int32 id = 0;
        
        /* format of a rsrc: URL is:
         *   rsrc://[TYPE][@NUM]/name[,mime]
         */
        
        NSLOG(netsurf, INFO, "*** Processing %s", c->url);
        
        if (strlen(c->url) < 7) {
                /* 7 is the minimum possible length (rsrc://) */
                msg.type = FETCH_ERROR;
                msg.data.error = "Malformed rsrc: URL";
                fetch_rsrc_send_callback(&msg, c);
                return false;
        }
        
        /* skip the rsrc: part */
        params = c->url + sizeof("rsrc://") - 1;
        
        /* find the slash */
        if ( (slash = strchr(params, '/')) == NULL) {
                msg.type = FETCH_ERROR;
                msg.data.error = "Malformed rsrc: URL";
                fetch_rsrc_send_callback(&msg, c);
                return false;
        }
 
        // doesn't exist in the filesystem but we should hit the internal types.
        c->mimetype = strdup(fetch_filetype(slash));
        c->name = strdup(slash + 1);
        
        if (c->mimetype == NULL) {
                msg.type = FETCH_ERROR;
                msg.data.error =
                        "Unable to allocate memory for mimetype in rsrc: URL";
                fetch_rsrc_send_callback(&msg, c);
                return false;
        }
 
        if (params[0] != '/') {
                uint8 c1, c2, c3, c4;
                if (sscanf(params, "%c%c%c%c", &c1, &c2, &c3, &c4) > 3) {
                        type = c1 << 24 | c2 << 16 | c3 << 8 | c4;
                        NSLOG(netsurf, INFO, "fetch_rsrc: type:%4.4s\n",
                              (char *)&type);
                }
        }
 
        NSLOG(netsurf, INFO, "fetch_rsrc: 0x%08lx, %ld, '%s'\n", type, id,
              c->name);
 
        bool found;
        if (id)
                found = gAppResources->HasResource(type, id);
        else
                found = gAppResources->HasResource(type, c->name);
        if (!found) {
                BString error("Cannot locate resource: ");
                if (id)
                        error << id;
                else
                        error << c->name;
                msg.type = FETCH_ERROR;
                msg.data.error = error.String();
                fetch_rsrc_send_callback(&msg, c);
                return false;
        }
 
        size_t len;
        const void *data;
        if (id)
                data = gAppResources->LoadResource(type, id, &len);
        else
                data = gAppResources->LoadResource(type, c->name, &len);
 
        if (!data) {
                msg.type = FETCH_ERROR;
                msg.data.error = "Cannot load rsrc: URL";
                fetch_rsrc_send_callback(&msg, c);
                return false;
        }
 
        c->datalen = len;
        c->data = (char *)malloc(c->datalen);
        if (c->data == NULL) {
                msg.type = FETCH_ERROR;
                msg.data.error = "Unable to allocate memory for rsrc: URL";
                fetch_rsrc_send_callback(&msg, c);
                return false;
        }
        memcpy(c->data, data, c->datalen);
 
        return true;
}
 
static void fetch_rsrc_poll(lwc_string *scheme)
{
        fetch_msg msg;
        struct fetch_rsrc_context *c, *next;
 
        if (ring == NULL) return;
        
        /* Iterate over ring, processing each pending fetch */
        c = ring;
        do {
                /* Take a copy of the next pointer as we may destroy
                 * the ring item we're currently processing */
                next = c->r_next;
 
                /* Ignore fetches that have been flagged as locked.
                 * This allows safe re-entrant calls to this function.
                 * Re-entrancy can occur if, as a result of a callback,
                 * the interested party causes fetch_poll() to be called 
                 * again.
                 */
                if (c->locked == true) {
                        continue;
                }
 
                /* Only process non-aborted fetches */
                if (!c->aborted && fetch_rsrc_process(c) == true) {
                        char header[64];
 
                        fetch_set_http_code(c->parent_fetch, 200);
                        NSLOG(netsurf, INFO,
                              "setting rsrc: MIME type to %s, length to %zd",
                              c->mimetype,
                              c->datalen);
                        /* Any callback can result in the fetch being aborted.
                         * Therefore, we _must_ check for this after _every_
                         * call to fetch_rsrc_send_callback().
                         */
                        snprintf(header, sizeof header, "Content-Type: %s",
                                        c->mimetype);
                        msg.type = FETCH_HEADER;
                        msg.data.header_or_data.buf = (const uint8_t *) header;
                        msg.data.header_or_data.len = strlen(header);
                        fetch_rsrc_send_callback(&msg, c);
 
                        snprintf(header, sizeof header, "Content-Length: %zd",
                                        c->datalen);
                        msg.type = FETCH_HEADER;
                        msg.data.header_or_data.buf = (const uint8_t *) header;
                        msg.data.header_or_data.len = strlen(header);
                        fetch_rsrc_send_callback(&msg, c);
 
                        if (!c->aborted) {
                                msg.type = FETCH_DATA;
                                msg.data.header_or_data.buf = (const uint8_t *) c->data;
                                msg.data.header_or_data.len = c->datalen;
                                fetch_rsrc_send_callback(&msg, c);
                        }
                        if (!c->aborted) {
                                msg.type = FETCH_FINISHED;
                                fetch_rsrc_send_callback(&msg, c);
                        }
                } else {
                        NSLOG(netsurf, INFO, "Processing of %s failed!",
                              c->url);
 
                        /* Ensure that we're unlocked here. If we aren't, 
                         * then fetch_rsrc_process() is broken.
                         */
                        assert(c->locked == false);
                }
 
                fetch_remove_from_queues(c->parent_fetch);
                fetch_free(c->parent_fetch);
 
                /* Advance to next ring entry, exiting if we've reached
                 * the start of the ring or the ring has become empty
                 */
        } while ( (c = next) != ring && ring != NULL);
}
 
/* BAppFileInfo is supposed to find the app's resources for us,
 * but this won't work if we ever want to be used as a replicant.
 * This trick should work regardless,
 */
static int find_app_resources()
{
        char path[B_PATH_NAME_LENGTH];
        if (nsbeos_find_app_path(path) < B_OK)
                return B_ERROR;
        //fprintf(stderr, "loading resources from '%s'\n", path);
 
        BFile file(path, B_READ_ONLY);
        if (file.InitCheck() < 0)
                return file.InitCheck();
        gAppResources = new BResources;
        status_t err;
        err = gAppResources->SetTo(&file);
        if (err >= B_OK)
                return B_OK;
        delete gAppResources;
        gAppResources = NULL;
        return err;
}
 
BResources *get_app_resources()
{
        return gAppResources;
}
 
void fetch_rsrc_register(void)
{
        lwc_string *scheme;
        int err;
        nserror ret;
 
        const struct fetcher_operation_table fetcher_ops_rsrc = {
                fetch_rsrc_initialise,
                fetch_rsrc_can_fetch,
                fetch_rsrc_setup,
                fetch_rsrc_start,
                fetch_rsrc_abort,
                fetch_rsrc_free,
                fetch_rsrc_poll,
                NULL,
                fetch_rsrc_finalise
        };
 
        err = find_app_resources();
 
        if (err < B_OK) {
                beos_warn_user("Resources", strerror(err));
                return;
        }
 
        if (lwc_intern_string("rsrc", SLEN("rsrc"), &scheme) != lwc_error_ok) {
                die("Failed to initialise the fetch module "
                                "(couldn't intern \"rsrc\").");
        }
 
        ret = fetcher_add(scheme, &fetcher_ops_rsrc);
        if (ret != NSERROR_OK) {
                die("unable to add rsrc fetcher.");
        }
}
 
void fetch_rsrc_unregister(void)
{
        delete gAppResources;
        gAppResources = NULL;
}