src/exp-templ.c

Template for internal export module.

/*
* Template for export modules
*/
/* $Id: exp-templ.c,v 1.10 2007-11-27 18:26:32 mschimek Exp $ */
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <limits.h>
#include "export.h"
typedef struct tmpl_instance
{
/* Common to all export modules */
vbi_export export;
/* Our private stuff */
/* Options */
int flip;
int day;
int prime;
double quality;
char * comment;
int weekday;
int counter;
} tmpl_instance;
/* Safer than tmpl_instance *tmpl = (tmpl_instance *)(vbi_export *) e */
#define TMPL(e) PARENT(e, tmpl_instance, export);
static vbi_export *
tmpl_new(void)
{
tmpl_instance *tmpl;
if (!(tmpl = calloc(1, sizeof(*tmpl))))
return NULL;
/*
* The caller will initialize tmpl->export.class for us
* and reset all options to their defaults, we only
* have to initialize our private stuff.
*/
tmpl->counter = 0;
return &tmpl->export;
}
static void
tmpl_delete(vbi_export *e)
{
tmpl_instance *tmpl = TMPL(e);
/* Uninitialize our private stuff and options */
if (tmpl->comment)
free(tmpl->comment);
free(tmpl);
}
/* convenience */
#define elements(array) (sizeof(array) / sizeof(array[0]))
/* N_(), _() are NLS functions, see info gettext. */
static const char *
string_menu_items[] = {
N_("Sunday"), N_("Monday"), N_("Tuesday"),
N_("Wednesday"), N_("Thursday"), N_("Friday"), N_("Saturday")
};
static int
int_menu_items[] = {
1, 3, 5, 7, 11, 13, 17, 19
};
static vbi_option_info
tmpl_options[] = {
VBI_OPTION_BOOL_INITIALIZER
/*
* Option keywords must be unique within their module
* and shall contain only "AZaz09_" (be filesystem safe that is).
* Note "network", "creator" and "reveal" are reserved generic
* options, filtered by the export api functions.
*/
("flip", N_("Boolean option"),
FALSE, N_("This is a boolean option")),
VBI_OPTION_INT_RANGE_INITIALIZER
("day", N_("Select a month day"),
/* default, min, max, step, has no tooltip */
13, 1, 31, 1, NULL),
VBI_OPTION_INT_MENU_INITIALIZER
("prime", N_("Select a prime"),
0, int_menu_items, elements(int_menu_items),
N_("Default is the first, '1'")),
VBI_OPTION_REAL_RANGE_INITIALIZER
("quality", N_("Compression quality"),
100, 1, 100, 0.01, NULL),
/* VBI_OPTION_REAL_MENU_INITIALIZER like int */
VBI_OPTION_STRING_INITIALIZER
("comment", N_("Add a comment"),
"default comment", N_("Another tooltip")),
VBI_OPTION_MENU_INITIALIZER
("weekday", N_("Select a weekday"),
2, string_menu_items, 7, N_("Default is Tuesday"))
};
/*
* Enumerate our options (optional if we have no options).
* Instead of using a table one could also dynamically create
* vbi_option_info's in tmpl_instance.
*/
static vbi_option_info *
option_enum(vbi_export *e, int index)
{
e = e;
/* Enumeration 0 ... n */
if (index < 0 || index >= (int) elements(tmpl_options))
return NULL;
return tmpl_options + index;
}
#define KEYWORD(str) (strcmp(keyword, str) == 0)
/*
* Get an option (optional if we have no options).
*/
static vbi_bool
option_get(vbi_export *e, const char *keyword, vbi_option_value *value)
{
tmpl_instance *tmpl = TMPL(e);
if (KEYWORD("flip")) {
value->num = tmpl->flip;
} else if (KEYWORD("day")) {
value->num = tmpl->day;
} else if (KEYWORD("prime")) {
value->num = tmpl->prime;
} else if (KEYWORD("quality")) {
value->dbl = tmpl->quality;
} else if (KEYWORD("comment")) {
if (!(value->str = vbi_export_strdup(e, NULL,
tmpl->comment ? tmpl->comment : "")))
return FALSE;
} else if (KEYWORD("weekday")) {
value->num = tmpl->weekday;
} else {
vbi_export_unknown_option(e, keyword);
return FALSE;
}
return TRUE; /* success */
}
/*
* Set an option (optional if we have no options).
*/
static vbi_bool
option_set(vbi_export *e, const char *keyword, va_list args)
{
tmpl_instance *tmpl = TMPL(e);
if (KEYWORD("flip")) {
tmpl->flip = !!va_arg(args, int);
} else if (KEYWORD("day")) {
int day = va_arg(args, int);
/* or clamp */
if (day < 1 || day > 31) {
vbi_export_invalid_option(e, keyword, day);
return FALSE;
}
tmpl->day = day;
} else if (KEYWORD("prime")) {
unsigned int i;
unsigned int d, dmin = UINT_MAX;
int value = va_arg(args, int);
/* or return an error */
for (i = 0; i < elements(int_menu_items); i++)
if ((d = abs(int_menu_items[i] - value)) < dmin) {
tmpl->prime = int_menu_items[i];
dmin = d;
}
} else if (KEYWORD("quality")) {
double quality = va_arg(args, double);
/* or return an error */
if (quality < 1)
quality = 1;
else if (quality > 100)
quality = 100;
tmpl->quality = quality;
} else if (KEYWORD("comment")) {
char *comment = va_arg(args, char *);
/* Note the option remains unchanged in case of error */
if (!vbi_export_strdup(e, &tmpl->comment, comment))
return FALSE;
} else if (KEYWORD("weekday")) {
int day = va_arg(args, int);
/* or return an error */
tmpl->weekday = day % 7;
} else {
vbi_export_unknown_option(e, keyword);
return FALSE;
}
return TRUE; /* success */
}
/*
* The output function, mandatory.
*/
static vbi_bool
export(vbi_export *e, vbi_page *pg)
{
tmpl_instance *tmpl = TMPL(e);
/* Write pg to target, that's all. */
vbi_export_printf (e, "Page %x.%x\n", pg->pgno, pg->subno);
tmpl->counter++; /* just for fun */
/*
* Should any of the module functions return unsuccessful
* they better post a description of the problem.
* Parameters like printf, no linefeeds '\n' please.
*/
/*
vbi_export_error_printf(_("Writing failed: %s"), strerror(errno));
*/
return FALSE; /* no success (since we didn't write anything) */
}
/*
* Let's describe us.
* You can leave away assignments unless mandatory.
*/
static vbi_export_info
info_tmpl = {
/* The mandatory keyword must be unique and shall
contain only "AZaz09_" */
.keyword = "templ",
/* When omitted this module can still be used by
libzvbi clients but won't be listed in a UI. */
.label = N_("Template"),
.tooltip = N_("This is just an export template"),
.mime_type = "misc/example",
.extension = "tmpl",
};
vbi_export_class
vbi_export_class_tmpl = {
._public = &info_tmpl,
/* Functions to allocate and free a tmpl_class vbi_export instance.
When you omit these, libzvbi will allocate a bare struct vbi_export */
._new = tmpl_new,
._delete = tmpl_delete,
/* Functions to enumerate, read and write options */
.option_enum = option_enum,
.option_get = option_get,
.option_set = option_set,
/* Function to export a page, mandatory */
.export = export
};
/*
* This is a constructor calling vbi_register_export_module().
* (Commented out since we don't want to register the example module.)
*/
#if 0
VBI_AUTOREG_EXPORT_MODULE(vbi_export_class_tmpl)
#endif
/*
Local variables:
c-set-style: K&R
c-basic-offset: 8
End:
*/
VBI_OPTION_STRING_INITIALIZER
#define VBI_OPTION_STRING_INITIALIZER(key_, label_, def_, tip_)
Definition export.h:602
VBI_OPTION_INT_MENU_INITIALIZER
#define VBI_OPTION_INT_MENU_INITIALIZER(key_, label_, def_, menu_, entries_, tip_)
Definition export.h:571
VBI_OPTION_INT_RANGE_INITIALIZER
#define VBI_OPTION_INT_RANGE_INITIALIZER(key_, label_, def_, min_, max_, step_, tip_)
Definition export.h:553
VBI_OPTION_REAL_RANGE_INITIALIZER
#define VBI_OPTION_REAL_RANGE_INITIALIZER(key_, label_, def_, min_, max_, step_, tip_)
Definition export.h:580
VBI_OPTION_BOOL_INITIALIZER
#define VBI_OPTION_BOOL_INITIALIZER(key_, label_, def_, tip_)
Definition export.h:539
vbi_export_strdup
char * vbi_export_strdup(vbi_export *export, char **d, const char *s)
Definition export.c:2054
vbi_export_unknown_option
void vbi_export_unknown_option(vbi_export *export, const char *keyword)
Definition export.c:1983
VBI_AUTOREG_EXPORT_MODULE
#define VBI_AUTOREG_EXPORT_MODULE(name)
Definition export.h:644
vbi_export_invalid_option
void vbi_export_invalid_option(vbi_export *export, const char *keyword,...)
Definition export.c:1997
VBI_OPTION_MENU_INITIALIZER
#define VBI_OPTION_MENU_INITIALIZER(key_, label_, def_, menu_, entries_, tip_)
Definition export.h:636
vbi_export_class
Definition export.h:432
vbi_export_info
Information about an export module.
Definition export.h:56
vbi_export
Definition export.h:333
vbi_option_info
Information about an export option.
Definition export.h:218
vbi_page
Formatted Teletext or Closed Caption page.
Definition format.h:265
vbi_page::subno
int subno
Definition format.h:284
vbi_page::pgno
int pgno
Definition format.h:279
vbi_option_value
Result of an option query.
Definition export.h:190