stage2/tparm.c - platform/external/grub - Git at Google

 /****************************************************************************
  * Copyright (c) 1998,2000,2002 Free Software Foundation, Inc.              *
  *                                                                          *
  * Permission is hereby granted, free of charge, to any person obtaining a  *
  * copy of this software and associated documentation files (the            *
  * "Software"), to deal in the Software without restriction, including      *
  * without limitation the rights to use, copy, modify, merge, publish,      *
  * distribute, distribute with modifications, sublicense, and/or sell       *
  * copies of the Software, and to permit persons to whom the Software is    *
  * furnished to do so, subject to the following conditions:                 *
  *                                                                          *
  * The above copyright notice and this permission notice shall be included  *
  * in all copies or substantial portions of the Software.                   *
  *                                                                          *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
  *                                                                          *
  * Except as contained in this notice, the name(s) of the above copyright   *
  * holders shall not be used in advertising or otherwise to promote the     *
  * sale, use or other dealings in this Software without prior written       *
  * authorization.                                                           *
  ****************************************************************************/

 /**********************************************************************
  * This code is a modification of lib_tparm.c found in ncurses-5.2. The
  * modification are for use in grub by replacing all libc function through
  * special grub functions. This also meant to delete all dynamic memory
  * allocation and replace it by a number of fixed buffers.
  *
  * Modifications by Tilmann Bubeck <t.bubeck@reinform.de> 2002
  **********************************************************************/

 /****************************************************************************
  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
  ****************************************************************************/

 /*
  *	tparm.c
  *
  */

 #include "shared.h"

 #include "tparm.h"

 /*
  * Common/troublesome character definitions
  */
 typedef char grub_bool;
 #define isdigit(c) ((c) >= '0' && (c) <= '9')
 #ifndef FALSE
 # define FALSE (0)
 #endif
 #ifndef TRUE
 # define TRUE (!FALSE)
 #endif
 #define MAX_FORMAT_LEN 256
 #define max(a,b) ((a) > (b) ? (a) : (b))

 //MODULE_ID("$Id: tparm.c,v 1.1 2002/11/29 20:39:24 okuji Exp $")

 /*
  *	char *
  *	tparm(string, ...)
  *
  *	Substitute the given parameters into the given string by the following
  *	rules (taken from terminfo(5)):
  *
  *	     Cursor addressing and other strings  requiring  parame-
  *	ters in the terminal are described by a parameterized string
  *	capability, with like escapes %x in  it.   For  example,  to
  *	address  the  cursor, the cup capability is given, using two
  *	parameters: the row and column to  address  to.   (Rows  and
  *	columns  are  numbered  from  zero and refer to the physical
  *	screen visible to the user, not to any  unseen  memory.)  If
  *	the terminal has memory relative cursor addressing, that can
  *	be indicated by
  *
  *	     The parameter mechanism uses  a  stack  and  special  %
  *	codes  to manipulate it.  Typically a sequence will push one
  *	of the parameters onto the stack and then print it  in  some
  *	format.  Often more complex operations are necessary.
  *
  *	     The % encodings have the following meanings:
  *
  *	     %%        outputs `%'
  *	     %c        print pop() like %c in printf()
  *	     %s        print pop() like %s in printf()
  *           %[[:]flags][width[.precision]][doxXs]
  *                     as in printf, flags are [-+#] and space
  *                     The ':' is used to avoid making %+ or %-
  *                     patterns (see below).
  *
  *	     %p[1-9]   push ith parm
  *	     %P[a-z]   set dynamic variable [a-z] to pop()
  *	     %g[a-z]   get dynamic variable [a-z] and push it
  *	     %P[A-Z]   set static variable [A-Z] to pop()
  *	     %g[A-Z]   get static variable [A-Z] and push it
  *	     %l        push strlen(pop)
  *	     %'c'      push char constant c
  *	     %{nn}     push integer constant nn
  *
  *	     %+ %- %* %/ %m
  *	               arithmetic (%m is mod): push(pop() op pop())
  *	     %& %| %^  bit operations: push(pop() op pop())
  *	     %= %> %<  logical operations: push(pop() op pop())
  *	     %A %O     logical and & or operations for conditionals
  *	     %! %~     unary operations push(op pop())
  *	     %i        add 1 to first two parms (for ANSI terminals)
  *
  *	     %? expr %t thenpart %e elsepart %;
  *	               if-then-else, %e elsepart is optional.
  *	               else-if's are possible ala Algol 68:
  *	               %? c1 %t b1 %e c2 %t b2 %e c3 %t b3 %e c4 %t b4 %e b5 %;
  *
  *	For those of the above operators which are binary and not commutative,
  *	the stack works in the usual way, with
  *			%gx %gy %m
  *	resulting in x mod y, not the reverse.
  */

 #define STACKSIZE	20

 typedef struct {
     union {
 	unsigned int num;
 	char *str;
     } data;
     grub_bool num_type;
 } stack_frame;

 static stack_frame stack[STACKSIZE];
 static int stack_ptr;

 static char out_buff[256];
 static int out_size = 256;
 static int out_used;

 static inline void
 get_space(int need)
 {
     need += out_used;
     if (need > out_size) {
 	// FIX ME! buffer full, what now?
 	;
     }
 }

 static inline void
 save_text(const char *fmt, const char *s, int len)
 {
     int s_len = grub_strlen(s);
     if (len > (int) s_len)
 	s_len = len;

     get_space(s_len + 1);

     (void) grub_sprintf(out_buff + out_used, fmt, s);
     out_used += grub_strlen(out_buff + out_used);
 }

 static inline void
 save_number(const char *fmt, int number, int len)
 {
     if (len < 30)
 	len = 30;		/* actually log10(MAX_INT)+1 */

     get_space(len + 1);

     (void) grub_sprintf(out_buff + out_used, fmt, number);
     out_used += grub_strlen(out_buff + out_used);
 }

 static inline void
 save_char(int c)
 {
     if (c == 0)
 	c = 0200;
     get_space(1);
     out_buff[out_used++] = c;
 }

 static inline void
 npush(int x)
 {
     if (stack_ptr < STACKSIZE) {
 	stack[stack_ptr].num_type = TRUE;
 	stack[stack_ptr].data.num = x;
 	stack_ptr++;
     }
 }

 static inline int
 npop(void)
 {
     int result = 0;
     if (stack_ptr > 0) {
 	stack_ptr--;
 	if (stack[stack_ptr].num_type)
 	    result = stack[stack_ptr].data.num;
     }
     return result;
 }

 static inline void
 spush(char *x)
 {
     if (stack_ptr < STACKSIZE) {
 	stack[stack_ptr].num_type = FALSE;
 	stack[stack_ptr].data.str = x;
 	stack_ptr++;
     }
 }

 static inline char *
 spop(void)
 {
     static char dummy[] = "";	/* avoid const-cast */
     char *result = dummy;
     if (stack_ptr > 0) {
 	stack_ptr--;
 	if (!stack[stack_ptr].num_type && stack[stack_ptr].data.str != 0)
 	    result = stack[stack_ptr].data.str;
     }
     return result;
 }

 static inline const char *
 parse_format(const char *s, char *format, int *len)
 {
     grub_bool done = FALSE;
     grub_bool allowminus = FALSE;
     grub_bool dot = FALSE;
     grub_bool err = FALSE;
     char *fmt = format;
     int prec = 0;
     int width = 0;
     int value = 0;

     *len = 0;
     *format++ = '%';
     while (*s != '\0' && !done) {
 	switch (*s) {
 	case 'c':		/* FALLTHRU */
 	case 'd':		/* FALLTHRU */
 	case 'o':		/* FALLTHRU */
 	case 'x':		/* FALLTHRU */
 	case 'X':		/* FALLTHRU */
 	case 's':
 	    *format++ = *s;
 	    done = TRUE;
 	    break;
 	case '.':
 	    *format++ = *s++;
 	    if (dot) {
 		err = TRUE;
 	    } else {
 		dot = TRUE;
 		prec = value;
 	    }
 	    value = 0;
 	    break;
 	case '#':
 	    *format++ = *s++;
 	    break;
 	case ' ':
 	    *format++ = *s++;
 	    break;
 	case ':':
 	    s++;
 	    allowminus = TRUE;
 	    break;
 	case '-':
 	    if (allowminus) {
 		*format++ = *s++;
 	    } else {
 		done = TRUE;
 	    }
 	    break;
 	default:
 	    if (isdigit(*s)) {
 		value = (value * 10) + (*s - '0');
 		if (value > 10000)
 		    err = TRUE;
 		*format++ = *s++;
 	    } else {
 		done = TRUE;
 	    }
 	}
     }

     /*
      * If we found an error, ignore (and remove) the flags.
      */
     if (err) {
 	prec = width = value = 0;
 	format = fmt;
 	*format++ = '%';
 	*format++ = *s;
     }

     if (dot)
 	width = value;
     else
 	prec = value;

     *format = '\0';
     /* return maximum string length in print */
     *len = (prec > width) ? prec : width;
     return s;
 }

 #define isUPPER(c) ((c) >= 'A' && (c) <= 'Z')
 #define isLOWER(c) ((c) >= 'a' && (c) <= 'z')

 static inline char *
 tparam_internal(const char *string, int *dataptr)
 {
 #define NUM_VARS 26
     char *p_is_s[9];
     int param[9];
     int lastpop;
     int popcount;
     int number;
     int len;
     int level;
     int x, y;
     int i;
     int len2;
     register const char *cp;
     static int len_fmt = MAX_FORMAT_LEN;
     static char dummy[] = "";
     static char format[MAX_FORMAT_LEN];
     static int dynamic_var[NUM_VARS];
     static int static_vars[NUM_VARS];

     out_used = 0;
     if (string == NULL)
 	return NULL;

     if ((len2 = grub_strlen(string)) > len_fmt) {
 	return NULL;
     }

     /*
      * Find the highest parameter-number referred to in the format string.
      * Use this value to limit the number of arguments copied from the
      * variable-length argument list.
      */

     number = 0;
     lastpop = -1;
     popcount = 0;
     grub_memset(p_is_s, 0, sizeof(p_is_s));

     /*
      * Analyze the string to see how many parameters we need from the varargs
      * list, and what their types are.  We will only accept string parameters
      * if they appear as a %l or %s format following an explicit parameter
      * reference (e.g., %p2%s).  All other parameters are numbers.
      *
      * 'number' counts coarsely the number of pop's we see in the string, and
      * 'popcount' shows the highest parameter number in the string.  We would
      * like to simply use the latter count, but if we are reading termcap
      * strings, there may be cases that we cannot see the explicit parameter
      * numbers.
      */
     for (cp = string; (cp - string) < (int) len2;) {
 	if (*cp == '%') {
 	    cp++;
 	    cp = parse_format(cp, format, &len);
 	    switch (*cp) {
 	    default:
 		break;

 	    case 'd':		/* FALLTHRU */
 	    case 'o':		/* FALLTHRU */
 	    case 'x':		/* FALLTHRU */
 	    case 'X':		/* FALLTHRU */
 	    case 'c':		/* FALLTHRU */
 		number++;
 		lastpop = -1;
 		break;

 	    case 'l':
 	    case 's':
 		if (lastpop > 0)
 		    p_is_s[lastpop - 1] = dummy;
 		++number;
 		break;

 	    case 'p':
 		cp++;
 		i = (*cp - '0');
 		if (i >= 0 && i <= 9) {
 		    lastpop = i;
 		    if (lastpop > popcount)
 			popcount = lastpop;
 		}
 		break;

 	    case 'P':
 	    case 'g':
 		cp++;
 		break;

 	    case '\'':
 		cp += 2;
 		lastpop = -1;
 		break;

 	    case '{':
 		cp++;
 		while (*cp >= '0' && *cp <= '9') {
 		    cp++;
 		}
 		break;

 	    case '+':
 	    case '-':
 	    case '*':
 	    case '/':
 	    case 'm':
 	    case 'A':
 	    case 'O':
 	    case '&':
 	    case '|':
 	    case '^':
 	    case '=':
 	    case '<':
 	    case '>':
 	    case '!':
 	    case '~':
 		lastpop = -1;
 		number += 2;
 		break;

 	    case 'i':
 		lastpop = -1;
 		if (popcount < 2)
 		    popcount = 2;
 		break;
 	    }
 	}
 	if (*cp != '\0')
 	    cp++;
     }

     if (number > 9)
 	number = 9;
     for (i = 0; i < max(popcount, number); i++) {
 	/*
 	 * A few caps (such as plab_norm) have string-valued parms.
 	 * We'll have to assume that the caller knows the difference, since
 	 * a char* and an int may not be the same size on the stack.
 	 */
 	if (p_is_s[i] != 0) {
 	  p_is_s[i] = (char *)(*(dataptr++));
 	} else {
 	  param[i] = (int)(*(dataptr++));
 	}
     }

     /*
      * This is a termcap compatibility hack.  If there are no explicit pop
      * operations in the string, load the stack in such a way that
      * successive pops will grab successive parameters.  That will make
      * the expansion of (for example) \E[%d;%dH work correctly in termcap
      * style, which means tparam() will expand termcap strings OK.
      */
     stack_ptr = 0;
     if (popcount == 0) {
 	popcount = number;
 	for (i = number - 1; i >= 0; i--)
 	    npush(param[i]);
     }

     while (*string) {
         /* skip delay timings */
 	if (*string == '$' && *(string + 1) == '<') {
 	    while( *string && *string != '>')
 	        string++;
 	    if ( *string == '>' ) string++;
 	} else if ( *string == '%') {
 	    string++;
 	    string = parse_format(string, format, &len);
 	    switch (*string) {
 	    default:
 		break;
 	    case '%':
 		save_char('%');
 		break;

 	    case 'd':		/* FALLTHRU */
 	    case 'o':		/* FALLTHRU */
 	    case 'x':		/* FALLTHRU */
 	    case 'X':		/* FALLTHRU */
 	    case 'c':		/* FALLTHRU */
 		save_number(format, npop(), len);
 		break;

 	    case 'l':
 		save_number("%d", strlen(spop()), 0);
 		break;

 	    case 's':
 		save_text(format, spop(), len);
 		break;

 	    case 'p':
 		string++;
 		i = (*string - '1');
 		if (i >= 0 && i < 9) {
 		    if (p_is_s[i])
 			spush(p_is_s[i]);
 		    else
 			npush(param[i]);
 		}
 		break;

 	    case 'P':
 		string++;
 		if (isUPPER(*string)) {
 		    i = (*string - 'A');
 		    static_vars[i] = npop();
 		} else if (isLOWER(*string)) {
 		    i = (*string - 'a');
 		    dynamic_var[i] = npop();
 		}
 		break;

 	    case 'g':
 		string++;
 		if (isUPPER(*string)) {
 		    i = (*string - 'A');
 		    npush(static_vars[i]);
 		} else if (isLOWER(*string)) {
 		    i = (*string - 'a');
 		    npush(dynamic_var[i]);
 		}
 		break;

 	    case '\'':
 		string++;
 		npush(*string);
 		string++;
 		break;

 	    case '{':
 		number = 0;
 		string++;
 		while (*string >= '0' && *string <= '9') {
 		    number = number * 10 + *string - '0';
 		    string++;
 		}
 		npush(number);
 		break;

 	    case '+':
 		npush(npop() + npop());
 		break;

 	    case '-':
 		y = npop();
 		x = npop();
 		npush(x - y);
 		break;

 	    case '*':
 		npush(npop() * npop());
 		break;

 	    case '/':
 		y = npop();
 		x = npop();
 		npush(y ? (x / y) : 0);
 		break;

 	    case 'm':
 		y = npop();
 		x = npop();
 		npush(y ? (x % y) : 0);
 		break;

 	    case 'A':
 		npush(npop() && npop());
 		break;

 	    case 'O':
 		npush(npop() || npop());
 		break;

 	    case '&':
 		npush(npop() & npop());
 		break;

 	    case '|':
 		npush(npop() | npop());
 		break;

 	    case '^':
 		npush(npop() ^ npop());
 		break;

 	    case '=':
 		y = npop();
 		x = npop();
 		npush(x == y);
 		break;

 	    case '<':
 		y = npop();
 		x = npop();
 		npush(x < y);
 		break;

 	    case '>':
 		y = npop();
 		x = npop();
 		npush(x > y);
 		break;

 	    case '!':
 		npush(!npop());
 		break;

 	    case '~':
 		npush(~npop());
 		break;

 	    case 'i':
 		if (p_is_s[0] == 0)
 		    param[0]++;
 		if (p_is_s[1] == 0)
 		    param[1]++;
 		break;

 	    case '?':
 		break;

 	    case 't':
 		x = npop();
 		if (!x) {
 		    /* scan forward for %e or %; at level zero */
 		    string++;
 		    level = 0;
 		    while (*string) {
 			if (*string == '%') {
 			    string++;
 			    if (*string == '?')
 				level++;
 			    else if (*string == ';') {
 				if (level > 0)
 				    level--;
 				else
 				    break;
 			    } else if (*string == 'e' && level == 0)
 				break;
 			}

 			if (*string)
 			    string++;
 		    }
 		}
 		break;

 	    case 'e':
 		/* scan forward for a %; at level zero */
 		string++;
 		level = 0;
 		while (*string) {
 		    if (*string == '%') {
 			string++;
 			if (*string == '?')
 			    level++;
 			else if (*string == ';') {
 			    if (level > 0)
 				level--;
 			    else
 				break;
 			}
 		    }

 		    if (*string)
 			string++;
 		}
 		break;

 	    case ';':
 		break;

 	    }			/* endswitch (*string) */
 	} else {             	/* endelse (*string == '%') */
 	    save_char(*string);
 	}

 	if (*string == '\0')
 	    break;

 	string++;
     }				/* endwhile (*string) */

     get_space(1);
     out_buff[out_used] = '\0';

     return (out_buff);
 }

 char *
 grub_tparm(const char *string,...)
 {
     char *result;
     int *dataptr = (int *) &string;

     dataptr++;

     result = tparam_internal(string, dataptr);

     return result;
 }
	/****************************************************************************
	* Copyright (c) 1998,2000,2002 Free Software Foundation, Inc. *
	* *
	* Permission is hereby granted, free of charge, to any person obtaining a *
	* copy of this software and associated documentation files (the *
	* "Software"), to deal in the Software without restriction, including *
	* without limitation the rights to use, copy, modify, merge, publish, *
	* distribute, distribute with modifications, sublicense, and/or sell *
	* copies of the Software, and to permit persons to whom the Software is *
	* furnished to do so, subject to the following conditions: *
	* *
	* The above copyright notice and this permission notice shall be included *
	* in all copies or substantial portions of the Software. *
	* *
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
	* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
	* IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
	* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
	* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
	* THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
	* *
	* Except as contained in this notice, the name(s) of the above copyright *
	* holders shall not be used in advertising or otherwise to promote the *
	* sale, use or other dealings in this Software without prior written *
	* authorization. *
	****************************************************************************/

	/**********************************************************************
	* This code is a modification of lib_tparm.c found in ncurses-5.2. The
	* modification are for use in grub by replacing all libc function through
	* special grub functions. This also meant to delete all dynamic memory
	* allocation and replace it by a number of fixed buffers.
	*
	* Modifications by Tilmann Bubeck <t.bubeck@reinform.de> 2002
	**********************************************************************/

	/****************************************************************************
	* Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995 *
	* and: Eric S. Raymond <esr@snark.thyrsus.com> *
	****************************************************************************/

	/*
	* tparm.c
	*
	*/

	#include "shared.h"

	#include "tparm.h"

	/*
	* Common/troublesome character definitions
	*/
	typedef char grub_bool;
	#define isdigit(c) ((c) >= '0' && (c) <= '9')
	#ifndef FALSE
	# define FALSE (0)
	#endif
	#ifndef TRUE
	# define TRUE (!FALSE)
	#endif
	#define MAX_FORMAT_LEN 256
	#define max(a,b) ((a) > (b) ? (a) : (b))

	//MODULE_ID("$Id: tparm.c,v 1.1 2002/11/29 20:39:24 okuji Exp $")

	/*
	* char *
	* tparm(string, ...)
	*
	* Substitute the given parameters into the given string by the following
	* rules (taken from terminfo(5)):
	*
	* Cursor addressing and other strings requiring parame-
	* ters in the terminal are described by a parameterized string
	* capability, with like escapes %x in it. For example, to
	* address the cursor, the cup capability is given, using two
	* parameters: the row and column to address to. (Rows and
	* columns are numbered from zero and refer to the physical
	* screen visible to the user, not to any unseen memory.) If
	* the terminal has memory relative cursor addressing, that can
	* be indicated by
	*
	* The parameter mechanism uses a stack and special %
	* codes to manipulate it. Typically a sequence will push one
	* of the parameters onto the stack and then print it in some
	* format. Often more complex operations are necessary.
	*
	* The % encodings have the following meanings:
	*
	* %% outputs `%'
	* %c print pop() like %c in printf()
	* %s print pop() like %s in printf()
	* %[[:]flags][width[.precision]][doxXs]
	* as in printf, flags are [-+#] and space
	* The ':' is used to avoid making %+ or %-
	* patterns (see below).
	*
	* %p[1-9] push ith parm
	* %P[a-z] set dynamic variable [a-z] to pop()
	* %g[a-z] get dynamic variable [a-z] and push it
	* %P[A-Z] set static variable [A-Z] to pop()
	* %g[A-Z] get static variable [A-Z] and push it
	* %l push strlen(pop)
	* %'c' push char constant c
	* %{nn} push integer constant nn
	*
	* %+ %- %* %/ %m
	* arithmetic (%m is mod): push(pop() op pop())
	* %& %\| %^ bit operations: push(pop() op pop())
	* %= %> %< logical operations: push(pop() op pop())
	* %A %O logical and & or operations for conditionals
	* %! %~ unary operations push(op pop())
	* %i add 1 to first two parms (for ANSI terminals)
	*
	* %? expr %t thenpart %e elsepart %;
	* if-then-else, %e elsepart is optional.
	* else-if's are possible ala Algol 68:
	* %? c1 %t b1 %e c2 %t b2 %e c3 %t b3 %e c4 %t b4 %e b5 %;
	*
	* For those of the above operators which are binary and not commutative,
	* the stack works in the usual way, with
	* %gx %gy %m
	* resulting in x mod y, not the reverse.
	*/

	#define STACKSIZE 20

	typedef struct {
	union {
	unsigned int num;
	char *str;
	} data;
	grub_bool num_type;
	} stack_frame;

	static stack_frame stack[STACKSIZE];
	static int stack_ptr;

	static char out_buff[256];
	static int out_size = 256;
	static int out_used;

	static inline void
	get_space(int need)
	{
	need += out_used;
	if (need > out_size) {
	// FIX ME! buffer full, what now?
	;
	}
	}

	static inline void
	save_text(const char fmt, const char s, int len)
	{
	int s_len = grub_strlen(s);
	if (len > (int) s_len)
	s_len = len;

	get_space(s_len + 1);

	(void) grub_sprintf(out_buff + out_used, fmt, s);
	out_used += grub_strlen(out_buff + out_used);
	}

	static inline void
	save_number(const char *fmt, int number, int len)
	{
	if (len < 30)
	len = 30; /* actually log10(MAX_INT)+1 */

	get_space(len + 1);

	(void) grub_sprintf(out_buff + out_used, fmt, number);
	out_used += grub_strlen(out_buff + out_used);
	}

	static inline void
	save_char(int c)
	{
	if (c == 0)
	c = 0200;
	get_space(1);
	out_buff[out_used++] = c;
	}

	static inline void
	npush(int x)
	{
	if (stack_ptr < STACKSIZE) {
	stack[stack_ptr].num_type = TRUE;
	stack[stack_ptr].data.num = x;
	stack_ptr++;
	}
	}

	static inline int
	npop(void)
	{
	int result = 0;
	if (stack_ptr > 0) {
	stack_ptr--;
	if (stack[stack_ptr].num_type)
	result = stack[stack_ptr].data.num;
	}
	return result;
	}

	static inline void
	spush(char *x)
	{
	if (stack_ptr < STACKSIZE) {
	stack[stack_ptr].num_type = FALSE;
	stack[stack_ptr].data.str = x;
	stack_ptr++;
	}
	}

	static inline char *
	spop(void)
	{
	static char dummy[] = ""; /* avoid const-cast */
	char *result = dummy;
	if (stack_ptr > 0) {
	stack_ptr--;
	if (!stack[stack_ptr].num_type && stack[stack_ptr].data.str != 0)
	result = stack[stack_ptr].data.str;
	}
	return result;
	}

	static inline const char *
	parse_format(const char s, char format, int *len)
	{
	grub_bool done = FALSE;
	grub_bool allowminus = FALSE;
	grub_bool dot = FALSE;
	grub_bool err = FALSE;
	char *fmt = format;
	int prec = 0;
	int width = 0;
	int value = 0;

	*len = 0;
	*format++ = '%';
	while (*s != '\0' && !done) {
	switch (*s) {
	case 'c': /* FALLTHRU */
	case 'd': /* FALLTHRU */
	case 'o': /* FALLTHRU */
	case 'x': /* FALLTHRU */
	case 'X': /* FALLTHRU */
	case 's':
	format++ = s;
	done = TRUE;
	break;
	case '.':
	format++ = s++;
	if (dot) {
	err = TRUE;
	} else {
	dot = TRUE;
	prec = value;
	}
	value = 0;
	break;
	case '#':
	format++ = s++;
	break;
	case ' ':
	format++ = s++;
	break;
	case ':':
	s++;
	allowminus = TRUE;
	break;
	case '-':
	if (allowminus) {
	format++ = s++;
	} else {
	done = TRUE;
	}
	break;
	default:
	if (isdigit(*s)) {
	value = (value * 10) + (*s - '0');
	if (value > 10000)
	err = TRUE;
	format++ = s++;
	} else {
	done = TRUE;
	}
	}
	}

	/*
	* If we found an error, ignore (and remove) the flags.
	*/
	if (err) {
	prec = width = value = 0;
	format = fmt;
	*format++ = '%';
	format++ = s;
	}

	if (dot)
	width = value;
	else
	prec = value;

	*format = '\0';
	/* return maximum string length in print */
	*len = (prec > width) ? prec : width;
	return s;
	}

	#define isUPPER(c) ((c) >= 'A' && (c) <= 'Z')
	#define isLOWER(c) ((c) >= 'a' && (c) <= 'z')

	static inline char *
	tparam_internal(const char string, int dataptr)
	{
	#define NUM_VARS 26
	char *p_is_s[9];
	int param[9];
	int lastpop;
	int popcount;
	int number;
	int len;
	int level;
	int x, y;
	int i;
	int len2;
	register const char *cp;
	static int len_fmt = MAX_FORMAT_LEN;
	static char dummy[] = "";
	static char format[MAX_FORMAT_LEN];
	static int dynamic_var[NUM_VARS];
	static int static_vars[NUM_VARS];

	out_used = 0;
	if (string == NULL)
	return NULL;

	if ((len2 = grub_strlen(string)) > len_fmt) {
	return NULL;
	}

	/*
	* Find the highest parameter-number referred to in the format string.
	* Use this value to limit the number of arguments copied from the
	* variable-length argument list.
	*/

	number = 0;
	lastpop = -1;
	popcount = 0;
	grub_memset(p_is_s, 0, sizeof(p_is_s));

	/*
	* Analyze the string to see how many parameters we need from the varargs
	* list, and what their types are. We will only accept string parameters
	* if they appear as a %l or %s format following an explicit parameter
	* reference (e.g., %p2%s). All other parameters are numbers.
	*
	* 'number' counts coarsely the number of pop's we see in the string, and
	* 'popcount' shows the highest parameter number in the string. We would
	* like to simply use the latter count, but if we are reading termcap
	* strings, there may be cases that we cannot see the explicit parameter
	* numbers.
	*/
	for (cp = string; (cp - string) < (int) len2;) {
	if (*cp == '%') {
	cp++;
	cp = parse_format(cp, format, &len);
	switch (*cp) {
	default:
	break;

	case 'd': /* FALLTHRU */
	case 'o': /* FALLTHRU */
	case 'x': /* FALLTHRU */
	case 'X': /* FALLTHRU */
	case 'c': /* FALLTHRU */
	number++;
	lastpop = -1;
	break;

	case 'l':
	case 's':
	if (lastpop > 0)
	p_is_s[lastpop - 1] = dummy;
	++number;
	break;

	case 'p':
	cp++;
	i = (*cp - '0');
	if (i >= 0 && i <= 9) {
	lastpop = i;
	if (lastpop > popcount)
	popcount = lastpop;
	}
	break;

	case 'P':
	case 'g':
	cp++;
	break;

	case '\'':
	cp += 2;
	lastpop = -1;
	break;

	case '{':
	cp++;
	while (cp >= '0' && cp <= '9') {
	cp++;
	}
	break;

	case '+':
	case '-':
	case '*':
	case '/':
	case 'm':
	case 'A':
	case 'O':
	case '&':
	case '\|':
	case '^':
	case '=':
	case '<':
	case '>':
	case '!':
	case '~':
	lastpop = -1;
	number += 2;
	break;

	case 'i':
	lastpop = -1;
	if (popcount < 2)
	popcount = 2;
	break;
	}
	}
	if (*cp != '\0')
	cp++;
	}

	if (number > 9)
	number = 9;
	for (i = 0; i < max(popcount, number); i++) {
	/*
	* A few caps (such as plab_norm) have string-valued parms.
	* We'll have to assume that the caller knows the difference, since
	* a char* and an int may not be the same size on the stack.
	*/
	if (p_is_s[i] != 0) {
	p_is_s[i] = (char )((dataptr++));
	} else {
	param[i] = (int)(*(dataptr++));
	}
	}

	/*
	* This is a termcap compatibility hack. If there are no explicit pop
	* operations in the string, load the stack in such a way that
	* successive pops will grab successive parameters. That will make
	* the expansion of (for example) \E[%d;%dH work correctly in termcap
	* style, which means tparam() will expand termcap strings OK.
	*/
	stack_ptr = 0;
	if (popcount == 0) {
	popcount = number;
	for (i = number - 1; i >= 0; i--)
	npush(param[i]);
	}

	while (*string) {
	/* skip delay timings */
	if (string == '$' && (string + 1) == '<') {
	while( string && string != '>')
	string++;
	if ( *string == '>' ) string++;
	} else if ( *string == '%') {
	string++;
	string = parse_format(string, format, &len);
	switch (*string) {
	default:
	break;
	case '%':
	save_char('%');
	break;

	case 'd': /* FALLTHRU */
	case 'o': /* FALLTHRU */
	case 'x': /* FALLTHRU */
	case 'X': /* FALLTHRU */
	case 'c': /* FALLTHRU */
	save_number(format, npop(), len);
	break;

	case 'l':
	save_number("%d", strlen(spop()), 0);
	break;

	case 's':
	save_text(format, spop(), len);
	break;

	case 'p':
	string++;
	i = (*string - '1');
	if (i >= 0 && i < 9) {
	if (p_is_s[i])
	spush(p_is_s[i]);
	else
	npush(param[i]);
	}
	break;

	case 'P':
	string++;
	if (isUPPER(*string)) {
	i = (*string - 'A');
	static_vars[i] = npop();
	} else if (isLOWER(*string)) {
	i = (*string - 'a');
	dynamic_var[i] = npop();
	}
	break;

	case 'g':
	string++;
	if (isUPPER(*string)) {
	i = (*string - 'A');
	npush(static_vars[i]);
	} else if (isLOWER(*string)) {
	i = (*string - 'a');
	npush(dynamic_var[i]);
	}
	break;

	case '\'':
	string++;
	npush(*string);
	string++;
	break;

	case '{':
	number = 0;
	string++;
	while (string >= '0' && string <= '9') {
	number = number * 10 + *string - '0';
	string++;
	}
	npush(number);
	break;

	case '+':
	npush(npop() + npop());
	break;

	case '-':
	y = npop();
	x = npop();
	npush(x - y);
	break;

	case '*':
	npush(npop() * npop());
	break;

	case '/':
	y = npop();
	x = npop();
	npush(y ? (x / y) : 0);
	break;

	case 'm':
	y = npop();
	x = npop();
	npush(y ? (x % y) : 0);
	break;

	case 'A':
	npush(npop() && npop());
	break;

	case 'O':
	npush(npop() \|\| npop());
	break;

	case '&':
	npush(npop() & npop());
	break;

	case '\|':
	npush(npop() \| npop());
	break;

	case '^':
	npush(npop() ^ npop());
	break;

	case '=':
	y = npop();
	x = npop();
	npush(x == y);
	break;

	case '<':
	y = npop();
	x = npop();
	npush(x < y);
	break;

	case '>':
	y = npop();
	x = npop();
	npush(x > y);
	break;

	case '!':
	npush(!npop());
	break;

	case '~':
	npush(~npop());
	break;

	case 'i':
	if (p_is_s[0] == 0)
	param[0]++;
	if (p_is_s[1] == 0)
	param[1]++;
	break;

	case '?':
	break;

	case 't':
	x = npop();
	if (!x) {
	/* scan forward for %e or %; at level zero */
	string++;
	level = 0;
	while (*string) {
	if (*string == '%') {
	string++;
	if (*string == '?')
	level++;
	else if (*string == ';') {
	if (level > 0)
	level--;
	else
	break;
	} else if (*string == 'e' && level == 0)
	break;
	}

	if (*string)
	string++;
	}
	}
	break;

	case 'e':
	/* scan forward for a %; at level zero */
	string++;
	level = 0;
	while (*string) {
	if (*string == '%') {
	string++;
	if (*string == '?')
	level++;
	else if (*string == ';') {
	if (level > 0)
	level--;
	else
	break;
	}
	}

	if (*string)
	string++;
	}
	break;

	case ';':
	break;

	} /* endswitch (string) /
	} else { /* endelse (string == '%') /
	save_char(*string);
	}

	if (*string == '\0')
	break;

	string++;
	} /* endwhile (string) /

	get_space(1);
	out_buff[out_used] = '\0';

	return (out_buff);
	}

	char *
	grub_tparm(const char *string,...)
	{
	char *result;
	int dataptr = (int ) &string;

	dataptr++;

	result = tparam_internal(string, dataptr);

	return result;
	}