common/hwconfig.c - filogic/uboot - Gitiles

 /*
  * An inteface for configuring a hardware via u-boot environment.
  *
  * Copyright (c) 2009  MontaVista Software, Inc.
  *
  * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
  *
  * 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.
  */

 #ifndef HWCONFIG_TEST
 #include <config.h>
 #include <common.h>
 #include <exports.h>
 #include <hwconfig.h>
 #include <linux/types.h>
 #include <linux/string.h>
 #else
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <assert.h>
 #define min(a, b) (((a) < (b)) ? (a) : (b))
 #endif /* HWCONFIG_TEST */

 DECLARE_GLOBAL_DATA_PTR;

 static const char *hwconfig_parse(const char *opts, size_t maxlen,
 				  const char *opt, char *stopchs, char eqch,
 				  size_t *arglen)
 {
 	size_t optlen = strlen(opt);
 	char *str;
 	const char *start = opts;
 	const char *end;

 next:
 	str = strstr(opts, opt);
 	end = str + optlen;
 	if (end - start > maxlen)
 		return NULL;

 	if (str && (str == opts || strpbrk(str - 1, stopchs) == str - 1) &&
 			(strpbrk(end, stopchs) == end || *end == eqch ||
 			 *end == '\0')) {
 		const char *arg_end;

 		if (!arglen)
 			return str;

 		if (*end != eqch)
 			return NULL;

 		arg_end = strpbrk(str, stopchs);
 		if (!arg_end)
 			*arglen = min(maxlen, strlen(str)) - optlen - 1;
 		else
 			*arglen = arg_end - end - 1;

 		return end + 1;
 	} else if (str) {
 		opts = end;
 		goto next;
 	}
 	return NULL;
 }

 const char cpu_hwconfig[] __attribute__((weak)) = "";
 const char board_hwconfig[] __attribute__((weak)) = "";

 #define HWCONFIG_PRE_RELOC_BUF_SIZE	128

 static const char *__hwconfig(const char *opt, size_t *arglen)
 {
 	const char *env_hwconfig = NULL, *ret;
 	char buf[HWCONFIG_PRE_RELOC_BUF_SIZE];

 	if (gd->flags & GD_FLG_ENV_READY) {
 		env_hwconfig = getenv("hwconfig");
 	} else {
 		/*
 		 * Use our own on stack based buffer before relocation to allow
 		 * accessing longer hwconfig strings that might be in the
 		 * environment before we've relocated.  This is pretty fragile
 		 * on both the use of stack and if the buffer is big enough.
 		 * However we will get a warning from getenv_f for the later.
 		 */
 		if ((getenv_f("hwconfig", buf, sizeof(buf))) > 0)
 			env_hwconfig = buf;
 	}

 	if (env_hwconfig) {
 		ret = hwconfig_parse(env_hwconfig, strlen(env_hwconfig),
 				      opt, ";", ':', arglen);
 		if (ret)
 			return ret;
 	}

 	ret = hwconfig_parse(board_hwconfig, strlen(board_hwconfig),
 			opt, ";", ':', arglen);
 	if (ret)
 		return ret;

 	return hwconfig_parse(cpu_hwconfig, strlen(cpu_hwconfig),
 			opt, ";", ':', arglen);
 }

 /*
  * hwconfig - query if a particular hwconfig option is specified
  * @opt:	a string representing an option
  *
  * This call can be used to find out whether U-Boot should configure
  * a particular hardware option.
  *
  * Returns non-zero value if the hardware option can be used and thus
  * should be configured, 0 otherwise.
  *
  * This function also returns non-zero value if CONFIG_HWCONFIG is
  * undefined.
  *
  * Returning non-zero value without CONFIG_HWCONFIG has its crucial
  * purpose: the hwconfig() call should be a "transparent" interface,
  * e.g. if a board doesn't need hwconfig facility, then we assume
  * that the board file only calls things that are actually used, so
  * hwconfig() will always return true result.
  */
 int hwconfig(const char *opt)
 {
 	return !!__hwconfig(opt, NULL);
 }

 /*
  * hwconfig_arg - get hwconfig option's argument
  * @opt:	a string representing an option
  * @arglen:	a pointer to an allocated size_t variable
  *
  * Unlike hwconfig() function, this function returns a pointer to the
  * start of the hwconfig arguments, if option is not found or it has
  * no specified arguments, the function returns NULL pointer.
  *
  * If CONFIG_HWCONFIG is undefined, the function returns "", and
  * arglen is set to 0.
  */
 const char *hwconfig_arg(const char *opt, size_t *arglen)
 {
 	return __hwconfig(opt, arglen);
 }

 /*
  * hwconfig_arg_cmp - compare hwconfig option's argument
  * @opt:	a string representing an option
  * @arg:	a string for comparing an option's argument
  *
  * This call is similar to hwconfig_arg, but instead of returning
  * hwconfig argument and its length, it is comparing it to @arg.
  *
  * Returns non-zero value if @arg matches, 0 otherwise.
  *
  * If CONFIG_HWCONFIG is undefined, the function returns a non-zero
  * value, i.e. the argument matches.
  */
 int hwconfig_arg_cmp(const char *opt, const char *arg)
 {
 	const char *argstr;
 	size_t arglen;

 	argstr = hwconfig_arg(opt, &arglen);
 	if (!argstr || arglen != strlen(arg))
 		return 0;

 	return !strncmp(argstr, arg, arglen);
 }

 /*
  * hwconfig_sub - query if a particular hwconfig sub-option is specified
  * @opt:	a string representing an option
  * @subopt:	a string representing a sub-option
  *
  * This call is similar to hwconfig(), except that it takes additional
  * argument @subopt. In this example:
  * 	"dr_usb:mode=peripheral"
  * "dr_usb" is an option, "mode" is a sub-option, and "peripheral" is its
  * argument.
  */
 int hwconfig_sub(const char *opt, const char *subopt)
 {
 	size_t arglen;
 	const char *arg;

 	arg = __hwconfig(opt, &arglen);
 	if (!arg)
 		return 0;
 	return !!hwconfig_parse(arg, arglen, subopt, ",;", '=', NULL);
 }

 /*
  * hwconfig_subarg - get hwconfig sub-option's argument
  * @opt:	a string representing an option
  * @subopt:	a string representing a sub-option
  * @subarglen:	a pointer to an allocated size_t variable
  *
  * This call is similar to hwconfig_arg(), except that it takes an additional
  * argument @subopt, and so works with sub-options.
  */
 const char *hwconfig_subarg(const char *opt, const char *subopt,
 			    size_t *subarglen)
 {
 	size_t arglen;
 	const char *arg;

 	arg = __hwconfig(opt, &arglen);
 	if (!arg)
 		return NULL;
 	return hwconfig_parse(arg, arglen, subopt, ",;", '=', subarglen);
 }

 /*
  * hwconfig_arg_cmp - compare hwconfig sub-option's argument
  * @opt:	a string representing an option
  * @subopt:	a string representing a sub-option
  * @subarg:	a string for comparing an sub-option's argument
  *
  * This call is similar to hwconfig_arg_cmp, except that it takes an additional
  * argument @subopt, and so works with sub-options.
  */
 int hwconfig_subarg_cmp(const char *opt, const char *subopt, const char *subarg)
 {
 	const char *argstr;
 	size_t arglen;

 	argstr = hwconfig_subarg(opt, subopt, &arglen);
 	if (!argstr || arglen != strlen(subarg))
 		return 0;

 	return !strncmp(argstr, subarg, arglen);
 }

 #ifdef HWCONFIG_TEST
 int main()
 {
 	const char *ret;
 	size_t len;

 	setenv("hwconfig", "key1:subkey1=value1,subkey2=value2;key2:value3;;;;"
 			   "key3;:,:=;key4", 1);

 	ret = hwconfig_arg("key1", &len);
 	printf("%zd %.*s\n", len, (int)len, ret);
 	assert(len == 29);
 	assert(hwconfig_arg_cmp("key1", "subkey1=value1,subkey2=value2"));
 	assert(!strncmp(ret, "subkey1=value1,subkey2=value2", len));

 	ret = hwconfig_subarg("key1", "subkey1", &len);
 	printf("%zd %.*s\n", len, (int)len, ret);
 	assert(len == 6);
 	assert(hwconfig_subarg_cmp("key1", "subkey1", "value1"));
 	assert(!strncmp(ret, "value1", len));

 	ret = hwconfig_subarg("key1", "subkey2", &len);
 	printf("%zd %.*s\n", len, (int)len, ret);
 	assert(len == 6);
 	assert(hwconfig_subarg_cmp("key1", "subkey2", "value2"));
 	assert(!strncmp(ret, "value2", len));

 	ret = hwconfig_arg("key2", &len);
 	printf("%zd %.*s\n", len, (int)len, ret);
 	assert(len == 6);
 	assert(hwconfig_arg_cmp("key2", "value3"));
 	assert(!strncmp(ret, "value3", len));

 	assert(hwconfig("key3"));
 	assert(hwconfig_arg("key4", &len) == NULL);
 	assert(hwconfig_arg("bogus", &len) == NULL);

 	unsetenv("hwconfig");

 	assert(hwconfig(NULL) == 0);
 	assert(hwconfig("") == 0);
 	assert(hwconfig("key3") == 0);

 	return 0;
 }
 #endif /* HWCONFIG_TEST */
	/*
	* An inteface for configuring a hardware via u-boot environment.
	*
	* Copyright (c) 2009 MontaVista Software, Inc.
	*
	* Author: Anton Vorontsov <avorontsov@ru.mvista.com>
	*
	* 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.
	*/

	#ifndef HWCONFIG_TEST
	#include <config.h>
	#include <common.h>
	#include <exports.h>
	#include <hwconfig.h>
	#include <linux/types.h>
	#include <linux/string.h>
	#else
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <assert.h>
	#define min(a, b) (((a) < (b)) ? (a) : (b))
	#endif /* HWCONFIG_TEST */

	DECLARE_GLOBAL_DATA_PTR;

	static const char hwconfig_parse(const char opts, size_t maxlen,
	const char opt, char stopchs, char eqch,
	size_t *arglen)
	{
	size_t optlen = strlen(opt);
	char *str;
	const char *start = opts;
	const char *end;

	next:
	str = strstr(opts, opt);
	end = str + optlen;
	if (end - start > maxlen)
	return NULL;

	if (str && (str == opts \|\| strpbrk(str - 1, stopchs) == str - 1) &&
	(strpbrk(end, stopchs) == end \|\| *end == eqch \|\|
	*end == '\0')) {
	const char *arg_end;

	if (!arglen)
	return str;

	if (*end != eqch)
	return NULL;

	arg_end = strpbrk(str, stopchs);
	if (!arg_end)
	*arglen = min(maxlen, strlen(str)) - optlen - 1;
	else
	*arglen = arg_end - end - 1;

	return end + 1;
	} else if (str) {
	opts = end;
	goto next;
	}
	return NULL;
	}

	const char cpu_hwconfig[] __attribute__((weak)) = "";
	const char board_hwconfig[] __attribute__((weak)) = "";

	#define HWCONFIG_PRE_RELOC_BUF_SIZE 128

	static const char __hwconfig(const char opt, size_t *arglen)
	{
	const char env_hwconfig = NULL, ret;
	char buf[HWCONFIG_PRE_RELOC_BUF_SIZE];

	if (gd->flags & GD_FLG_ENV_READY) {
	env_hwconfig = getenv("hwconfig");
	} else {
	/*
	* Use our own on stack based buffer before relocation to allow
	* accessing longer hwconfig strings that might be in the
	* environment before we've relocated. This is pretty fragile
	* on both the use of stack and if the buffer is big enough.
	* However we will get a warning from getenv_f for the later.
	*/
	if ((getenv_f("hwconfig", buf, sizeof(buf))) > 0)
	env_hwconfig = buf;
	}

	if (env_hwconfig) {
	ret = hwconfig_parse(env_hwconfig, strlen(env_hwconfig),
	opt, ";", ':', arglen);
	if (ret)
	return ret;
	}

	ret = hwconfig_parse(board_hwconfig, strlen(board_hwconfig),
	opt, ";", ':', arglen);
	if (ret)
	return ret;

	return hwconfig_parse(cpu_hwconfig, strlen(cpu_hwconfig),
	opt, ";", ':', arglen);
	}

	/*
	* hwconfig - query if a particular hwconfig option is specified
	* @opt: a string representing an option
	*
	* This call can be used to find out whether U-Boot should configure
	* a particular hardware option.
	*
	* Returns non-zero value if the hardware option can be used and thus
	* should be configured, 0 otherwise.
	*
	* This function also returns non-zero value if CONFIG_HWCONFIG is
	* undefined.
	*
	* Returning non-zero value without CONFIG_HWCONFIG has its crucial
	* purpose: the hwconfig() call should be a "transparent" interface,
	* e.g. if a board doesn't need hwconfig facility, then we assume
	* that the board file only calls things that are actually used, so
	* hwconfig() will always return true result.
	*/
	int hwconfig(const char *opt)
	{
	return !!__hwconfig(opt, NULL);
	}

	/*
	* hwconfig_arg - get hwconfig option's argument
	* @opt: a string representing an option
	* @arglen: a pointer to an allocated size_t variable
	*
	* Unlike hwconfig() function, this function returns a pointer to the
	* start of the hwconfig arguments, if option is not found or it has
	* no specified arguments, the function returns NULL pointer.
	*
	* If CONFIG_HWCONFIG is undefined, the function returns "", and
	* arglen is set to 0.
	*/
	const char hwconfig_arg(const char opt, size_t *arglen)
	{
	return __hwconfig(opt, arglen);
	}

	/*
	* hwconfig_arg_cmp - compare hwconfig option's argument
	* @opt: a string representing an option
	* @arg: a string for comparing an option's argument
	*
	* This call is similar to hwconfig_arg, but instead of returning
	* hwconfig argument and its length, it is comparing it to @arg.
	*
	* Returns non-zero value if @arg matches, 0 otherwise.
	*
	* If CONFIG_HWCONFIG is undefined, the function returns a non-zero
	* value, i.e. the argument matches.
	*/
	int hwconfig_arg_cmp(const char opt, const char arg)
	{
	const char *argstr;
	size_t arglen;

	argstr = hwconfig_arg(opt, &arglen);
	if (!argstr \|\| arglen != strlen(arg))
	return 0;

	return !strncmp(argstr, arg, arglen);
	}

	/*
	* hwconfig_sub - query if a particular hwconfig sub-option is specified
	* @opt: a string representing an option
	* @subopt: a string representing a sub-option
	*
	* This call is similar to hwconfig(), except that it takes additional
	* argument @subopt. In this example:
	* "dr_usb:mode=peripheral"
	* "dr_usb" is an option, "mode" is a sub-option, and "peripheral" is its
	* argument.
	*/
	int hwconfig_sub(const char opt, const char subopt)
	{
	size_t arglen;
	const char *arg;

	arg = __hwconfig(opt, &arglen);
	if (!arg)
	return 0;
	return !!hwconfig_parse(arg, arglen, subopt, ",;", '=', NULL);
	}

	/*
	* hwconfig_subarg - get hwconfig sub-option's argument
	* @opt: a string representing an option
	* @subopt: a string representing a sub-option
	* @subarglen: a pointer to an allocated size_t variable
	*
	* This call is similar to hwconfig_arg(), except that it takes an additional
	* argument @subopt, and so works with sub-options.
	*/
	const char hwconfig_subarg(const char opt, const char *subopt,
	size_t *subarglen)
	{
	size_t arglen;
	const char *arg;

	arg = __hwconfig(opt, &arglen);
	if (!arg)
	return NULL;
	return hwconfig_parse(arg, arglen, subopt, ",;", '=', subarglen);
	}

	/*
	* hwconfig_arg_cmp - compare hwconfig sub-option's argument
	* @opt: a string representing an option
	* @subopt: a string representing a sub-option
	* @subarg: a string for comparing an sub-option's argument
	*
	* This call is similar to hwconfig_arg_cmp, except that it takes an additional
	* argument @subopt, and so works with sub-options.
	*/
	int hwconfig_subarg_cmp(const char opt, const char subopt, const char *subarg)
	{
	const char *argstr;
	size_t arglen;

	argstr = hwconfig_subarg(opt, subopt, &arglen);
	if (!argstr \|\| arglen != strlen(subarg))
	return 0;

	return !strncmp(argstr, subarg, arglen);
	}

	#ifdef HWCONFIG_TEST
	int main()
	{
	const char *ret;
	size_t len;

	setenv("hwconfig", "key1:subkey1=value1,subkey2=value2;key2:value3;;;;"
	"key3;:,:=;key4", 1);

	ret = hwconfig_arg("key1", &len);
	printf("%zd %.*s\n", len, (int)len, ret);
	assert(len == 29);
	assert(hwconfig_arg_cmp("key1", "subkey1=value1,subkey2=value2"));
	assert(!strncmp(ret, "subkey1=value1,subkey2=value2", len));

	ret = hwconfig_subarg("key1", "subkey1", &len);
	printf("%zd %.*s\n", len, (int)len, ret);
	assert(len == 6);
	assert(hwconfig_subarg_cmp("key1", "subkey1", "value1"));
	assert(!strncmp(ret, "value1", len));

	ret = hwconfig_subarg("key1", "subkey2", &len);
	printf("%zd %.*s\n", len, (int)len, ret);
	assert(len == 6);
	assert(hwconfig_subarg_cmp("key1", "subkey2", "value2"));
	assert(!strncmp(ret, "value2", len));

	ret = hwconfig_arg("key2", &len);
	printf("%zd %.*s\n", len, (int)len, ret);
	assert(len == 6);
	assert(hwconfig_arg_cmp("key2", "value3"));
	assert(!strncmp(ret, "value3", len));

	assert(hwconfig("key3"));
	assert(hwconfig_arg("key4", &len) == NULL);
	assert(hwconfig_arg("bogus", &len) == NULL);

	unsetenv("hwconfig");

	assert(hwconfig(NULL) == 0);
	assert(hwconfig("") == 0);
	assert(hwconfig("key3") == 0);

	return 0;
	}
	#endif /* HWCONFIG_TEST */