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/*
* Copyright (C) 2009-2013 Tobias Brunner
* Copyright (C) 2006-2008 Martin Willi
* HSR Hochschule fuer Technik Rapperswil
*
* 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. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* 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.
*/
#include "printf_hook.h"
#include <utils/utils.h>
#include <utils/debug.h>
#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include <printf.h>
typedef struct private_printf_hook_t private_printf_hook_t;
typedef struct printf_hook_handler_t printf_hook_handler_t;
/**
* private data of printf_hook
*/
struct private_printf_hook_t {
/**
* public functions
*/
printf_hook_t public;
};
/**
* struct with information about a registered handler
*/
struct printf_hook_handler_t {
/**
* callback function
*/
printf_hook_function_t hook;
/**
* number of arguments
*/
int numargs;
/**
* types of the arguments, PA_*
*/
int argtypes[3];
};
/**
* Data to pass to a printf hook.
*/
struct printf_hook_data_t {
/**
* Output FILE stream
*/
FILE *stream;;
};
/* A-Z | 6 other chars | a-z */
static printf_hook_handler_t *printf_hooks[58];
#define SPEC_TO_INDEX(spec) ((int)(spec) - (int)'A')
/**
* Glibc variant of print_in_hook()
*/
size_t print_in_hook(printf_hook_data_t *data, char *fmt, ...)
{
ssize_t written;
va_list args;
va_start(args, fmt);
written = vfprintf(data->stream, fmt, args);
va_end(args);
if (written < 0)
{
written = 0;
}
return written;
}
/**
* Printf hook print function. This is actually of type "printf_function",
* however glibc does it typedef to function, but uclibc to a pointer.
* So we redefine it here.
*/
static int custom_print(FILE *stream, const struct printf_info *info,
const void *const *args)
{
printf_hook_spec_t spec;
printf_hook_handler_t *handler;
printf_hook_data_t data = {
.stream = stream,
};
handler = printf_hooks[SPEC_TO_INDEX(info->spec)];
spec.hash = info->alt;
spec.plus = info->showsign;
spec.minus = info->left;
spec.width = info->width;
return handler->hook(&data, &spec, args);
}
/**
* Printf hook arginfo function, which is actually of type
* "printf_arginfo_[size_]function".
*/
static int custom_arginfo(const struct printf_info *info, size_t n, int *argtypes
#ifdef HAVE_PRINTF_SPECIFIER
, int *size
#endif
)
{
int i;
printf_hook_handler_t *handler;
handler = printf_hooks[SPEC_TO_INDEX(info->spec)];
if (handler->numargs <= n)
{
for (i = 0; i < handler->numargs; ++i)
{
argtypes[i] = handler->argtypes[i];
}
}
/* we never set "size", as we have no user defined types */
return handler->numargs;
}
METHOD(printf_hook_t, add_handler, void,
private_printf_hook_t *this, char spec,
printf_hook_function_t hook, ...)
{
int i = -1;
bool failed = FALSE;
printf_hook_handler_t *handler;
printf_hook_argtype_t argtype;
va_list args;
if (SPEC_TO_INDEX(spec) <= -1 ||
SPEC_TO_INDEX(spec) >= countof(printf_hooks))
{
DBG1(DBG_LIB, "'%c' is not a valid printf hook specifier, "
"not registered!", spec);
return;
}
INIT(handler,
.hook = hook,
);
va_start(args, hook);
while (!failed)
{
argtype = va_arg(args, printf_hook_argtype_t);
if (argtype == PRINTF_HOOK_ARGTYPE_END)
{
break;
}
if (++i >= countof(handler->argtypes))
{
DBG1(DBG_LIB, "Too many arguments for printf hook with "
"specifier '%c', not registered!", spec);
failed = TRUE;
break;
}
switch (argtype)
{
case PRINTF_HOOK_ARGTYPE_INT:
handler->argtypes[i] = PA_INT;
break;
case PRINTF_HOOK_ARGTYPE_POINTER:
handler->argtypes[i] = PA_POINTER;
break;
default:
DBG1(DBG_LIB, "Invalid printf hook arg type for '%c'", spec);
failed = TRUE;
break;
}
}
va_end(args);
handler->numargs = i + 1;
if (!failed && handler->numargs > 0)
{
# ifdef HAVE_PRINTF_SPECIFIER
register_printf_specifier(spec, custom_print, custom_arginfo);
# else
register_printf_function(spec, custom_print, custom_arginfo);
# endif
printf_hooks[SPEC_TO_INDEX(spec)] = handler;
}
else
{
free(handler);
}
}
METHOD(printf_hook_t, destroy, void,
private_printf_hook_t *this)
{
int i;
for (i = 0; i < countof(printf_hooks); i++)
{
free(printf_hooks[i]);
}
free(this);
}
/*
* see header file
*/
printf_hook_t *printf_hook_create()
{
private_printf_hook_t *this;
INIT(this,
.public = {
.add_handler = _add_handler,
.destroy = _destroy,
},
);
memset(printf_hooks, 0, sizeof(printf_hooks));
return &this->public;
}
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