netsurf/content/content.h

307 lines
11 KiB
C

/*
* This file is part of NetSurf, http://netsurf.sourceforge.net/
* Licensed under the GNU General Public License,
* http://www.opensource.org/licenses/gpl-license
* Copyright 2004 James Bursa <bursa@users.sourceforge.net>
* Copyright 2003 Philip Pemberton <philpem@users.sourceforge.net>
*/
/** \file
* Content handling (interface).
*
* The content functions manipulate struct contents, which correspond to URLs.
*
* Each content has a type. The type is used to call a specific implementation
* of functions such as content_process_data().
*
* The source data fetched from the URL is placed in the source_data buffer as
* it arrives.
*
* Contents have an associated set of users, which are informed by a callback
* when the state of the content changes or something interesting happens.
*
* Optionally, contents may have instances (depending on type). Instances
* represent copies of the same URL, for example if a page is open in two
* windows, or a page contains the same image twice.
*
* The status of a content follows a fixed order. Certain content functions
* change the state, and each change of state results in a message to all users
* of the content. The diagram below shows this:
* \dot
* digraph status {
* node [shape=plaintext, fontname=Helvetica, fontsize=9];
* edge [fontname=Helvetica, fontsize=9];
*
* content_create -> TYPE_UNKNOWN [style=bold];
* TYPE_UNKNOWN -> content_set_type [style=bold];
* content_set_type -> LOADING [label=MSG_LOADING, style=bold];
* content_set_type -> LOADING [label="MSG_NEWPTR\nMSG_LOADING"];
* content_set_type -> ERROR [label=MSG_ERROR];
* LOADING -> content_process_data [style=bold];
* content_process_data -> LOADING [style=bold];
* content_process_data -> ERROR [label=MSG_ERROR];
* LOADING -> content_convert [style=bold];
* content_convert -> READY [label=MSG_READY, style=bold];
* content_convert -> DONE [label="MSG_READY\nMSG_DONE", style=bold];
* content_convert -> ERROR [label=MSG_ERROR];
* READY -> READY [style=bold];
* READY -> DONE [label=MSG_DONE, style=bold];
* READY -> content_stop;
* content_stop -> DONE [label=MSG_DONE];
*
* TYPE_UNKNOWN [shape=ellipse];
* LOADING [shape=ellipse];
* READY [shape=ellipse];
* DONE [shape=ellipse];
* ERROR [shape=ellipse];
* }
* \enddot
*
* To implement a new content type, implement the following functions:
*
* - <i>type</i>_create(): called to initialise type-specific fields in the
* content structure. Optional.
*
* - <i>type</i>_process_data(): called when some data arrives. Optional.
*
* - <i>type</i>_convert(): called when data has finished arriving. The
* content needs to be converted for display. Must set the status to one of
* CONTENT_STATUS_READY or CONTENT_STATUS_DONE if no error occurs. Optional,
* but probably required for non-trivial types.
*
* - <i>type</i>_reformat(): called when, for example, the window has been
* resized, and the content needs reformatting for the new size. Optional.
*
* - <i>type</i>_destroy(): called when the content is being destroyed. Free all
* resources. Optional.
*
* - <i>type</i>_redraw(): called to plot the content to screen.
*
* - <i>type</i>_stop(): called when the user interrupts in status
* CONTENT_STATUS_READY. Must stop any processing and set the status to
* CONTENT_STATUS_DONE. Required iff the status can be CONTENT_STATUS_READY.
*
* - <i>type</i>_open(): called when a window containing the content is
* opened. Probably only makes sense if no_share is set for the content type
* in handler_map. Optional.
*
* - <i>type</i>_close(): called when the window containing the content is
* closed. Optional.
*
* - <i>type</i>_create(), <i>type</i>_process_data(), <i>type</i>_convert():
* if an error occurs, must broadcast CONTENT_MSG_ERROR and return false.
* Optionally use warn_user() for serious errors. The _destroy function will
* be called soon after.
*/
#ifndef _NETSURF_DESKTOP_CONTENT_H_
#define _NETSURF_DESKTOP_CONTENT_H_
#include "netsurf/utils/config.h"
#include "netsurf/content/content_type.h"
#include "netsurf/css/css.h"
#include "netsurf/render/html.h"
#ifdef WITH_JPEG
#include "netsurf/riscos/jpeg.h"
#endif
#ifdef WITH_GIF
#include "netsurf/riscos/gif.h"
#endif
#ifdef WITH_PLUGIN
#include "netsurf/riscos/plugin.h"
#endif
#ifdef WITH_PNG
#include "netsurf/riscos/png.h"
#endif
#ifdef WITH_MNG
#include "netsurf/riscos/mng.h"
#endif
#ifdef WITH_SPRITE
#include "netsurf/riscos/sprite.h"
#endif
#ifdef WITH_DRAW
#include "netsurf/riscos/draw.h"
#endif
struct box;
struct browser_window;
struct content;
struct fetch;
struct object_params;
/** Used in callbacks to indicate what has occurred. */
typedef enum {
CONTENT_MSG_LOADING, /**< fetching or converting */
CONTENT_MSG_READY, /**< may be displayed */
CONTENT_MSG_DONE, /**< finished */
CONTENT_MSG_ERROR, /**< error occurred */
CONTENT_MSG_STATUS, /**< new status string */
CONTENT_MSG_REDIRECT, /**< replacement URL */
CONTENT_MSG_REFORMAT, /**< content_reformat done */
CONTENT_MSG_REDRAW, /**< needs redraw (eg. new animation frame) */
CONTENT_MSG_NEWPTR, /**< address of structure has changed */
#ifdef WITH_AUTH
CONTENT_MSG_AUTH /**< authentication required */
#endif
} content_msg;
/** Extra data for some content_msg messages. */
union content_msg_data {
const char *error; /**< Error message, for CONTENT_MSG_ERROR. */
char *redirect; /**< Redirect URL, for CONTENT_MSG_REDIRECT. */
/** Area of content which needs redrawing, for CONTENT_MSG_REDRAW. */
struct {
float x, y, width, height;
/** Redraw the area fully. If false, object must be set,
* and only the object will be redrawn. */
bool full_redraw;
/** Object to redraw if full_redraw is false. */
struct content *object;
/** Coordinates to plot object at. */
float object_x, object_y;
/** Dimensions to plot object with. */
float object_width, object_height;
} redraw;
char *auth_realm; /**< Realm, for CONTENT_MSG_AUTH. */
};
/** Linked list of users of a content. */
struct content_user
{
void (*callback)(content_msg msg, struct content *c, void *p1,
void *p2, union content_msg_data data);
void *p1;
void *p2;
bool stop;
struct content_user *next;
};
/** Corresponds to a single URL. */
struct content {
char *url; /**< URL, in standard form as from url_join. */
content_type type; /**< Type of content. */
char *mime_type; /**< Original MIME type of data, or 0. */
enum {
CONTENT_STATUS_TYPE_UNKNOWN, /**< Type not yet known. */
CONTENT_STATUS_LOADING, /**< Content is being fetched or
converted and is not safe to display. */
CONTENT_STATUS_READY, /**< Some parts of content still being
loaded, but can be displayed. */
CONTENT_STATUS_DONE, /**< All finished. */
CONTENT_STATUS_ERROR /**< Error occurred, content will be
destroyed imminently. */
} status; /**< Current status. */
int width, height; /**< Dimensions, if applicable. */
int available_width; /**< Available width (eg window width). */
/** Data dependent on type. */
union {
struct content_html_data html;
struct content_css_data css;
#ifdef WITH_JPEG
struct content_jpeg_data jpeg;
#endif
#ifdef WITH_GIF
struct content_gif_data gif;
#endif
#ifdef WITH_PNG
struct content_png_data png;
#endif
#ifdef WITH_MNG
struct content_mng_data mng;
#endif
#ifdef WITH_SPRITE
struct content_sprite_data sprite;
#endif
#ifdef WITH_DRAW
struct content_draw_data draw;
#endif
#ifdef WITH_PLUGIN
struct content_plugin_data plugin;
#endif
} data;
/** This content may be given to new users. Indicates that the content
* was fetched using a simple GET, has not expired, and may be
* shared between users. */
bool fresh;
unsigned int size; /**< Estimated size of all data
associated with this content. */
char *title; /**< Title for browser window. */
unsigned int active; /**< Number of child fetches or
conversions currently in progress. */
struct content_user *user_list; /**< List of users. */
char status_message[80]; /**< Text for status bar. */
struct fetch *fetch; /**< Associated fetch, or 0. */
char *source_data; /**< Source data, as received. */
unsigned long source_size; /**< Amount of data fetched so far. */
unsigned long total_size; /**< Total data size, 0 if unknown. */
bool no_error_pages; /**< Used by fetchcache(). */
/** Array of first n rendering errors or warnings. */
struct {
const char *token;
unsigned int line; /**< Line no, 0 if not applicable. */
} error_list[40];
unsigned int error_count; /**< Number of valid error entries. */
struct content *prev; /**< Previous in global content list. */
struct content *next; /**< Next in global content list. */
};
extern struct content *content_list;
extern const char *content_type_name[];
extern const char *content_status_name[];
content_type content_lookup(const char *mime_type);
struct content * content_create(const char *url);
struct content * content_get(const char *url);
bool content_set_type(struct content *c, content_type type,
const char *mime_type, const char *params[]);
void content_set_status(struct content *c, const char *status_message, ...);
bool content_process_data(struct content *c, const char *data,
unsigned int size);
void content_convert(struct content *c, int width, int height);
void content_reformat(struct content *c, int width, int height);
void content_clean(void);
void content_reset(struct content *c);
void content_quit(void);
bool content_redraw(struct content *c, int x, int y,
int width, int height,
int clip_x0, int clip_y0, int clip_x1, int clip_y1,
float scale);
void content_add_user(struct content *c,
void (*callback)(content_msg msg, struct content *c, void *p1,
void *p2, union content_msg_data data),
void *p1, void *p2);
struct content_user * content_find_user(struct content *c,
void (*callback)(content_msg msg, struct content *c, void *p1,
void *p2, union content_msg_data data),
void *p1, void *p2);
void content_remove_user(struct content *c,
void (*callback)(content_msg msg, struct content *c, void *p1,
void *p2, union content_msg_data data),
void *p1, void *p2);
void content_broadcast(struct content *c, content_msg msg,
union content_msg_data data);
void content_stop(struct content *c,
void (*callback)(content_msg msg, struct content *c, void *p1,
void *p2, union content_msg_data data),
void *p1, void *p2);
void content_open(struct content *c, struct browser_window *bw,
struct content *page, struct box *box,
struct object_params *params);
void content_close(struct content *c);
void content_add_error(struct content *c, const char *token,
unsigned int line);
#endif