/*! @file lsame.c

 * \brief  Check if CA is the same letter as CB regardless of case.

 *

 * 

 * -- LAPACK auxiliary routine (version 2.0) --   

 *      Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,   

 *      Courant Institute, Argonne National Lab, and Rice University   

 *      September 30, 1994   

 * 

 */

#include "slu_Cnames.h"

/*! \brief

    Purpose   

    =======   

    LSAME returns .TRUE. if CA is the same letter as CB regardless of case.   

    Arguments   

    =========   

    CA      (input) CHARACTER*1   

    CB      (input) CHARACTER*1   

            CA and CB specify the single characters to be compared.   

   ===================================================================== 

*/  

int lsame_(char *ca, char *cb)

{

    /* System generated locals */

    int ret_val;

    /* Local variables */

    int inta, intb, zcode;

    ret_val = *(unsigned char *)ca == *(unsigned char *)cb;

    if (ret_val) {

	return ret_val;

    }

    /* Now test for equivalence if both characters are alphabetic. */

    zcode = 'Z';

    /* Use 'Z' rather than 'A' so that ASCII can be detected on Prime   

       machines, on which ICHAR returns a value with bit 8 set.   

       ICHAR('A') on Prime machines returns 193 which is the same as   

       ICHAR('A') on an EBCDIC machine. */

    inta = *(unsigned char *)ca;

    intb = *(unsigned char *)cb;

    if (zcode == 90 || zcode == 122) {

	/* ASCII is assumed - ZCODE is the ASCII code of either lower or   

          upper case 'Z'. */

	if (inta >= 97 && inta <= 122) inta += -32;

	if (intb >= 97 && intb <= 122) intb += -32;

    } else if (zcode == 233 || zcode == 169) {

	/* EBCDIC is assumed - ZCODE is the EBCDIC code of either lower or   

          upper case 'Z'. */

	if (inta >= 129 && inta <= 137 || inta >= 145 && inta <= 153 || inta 

		>= 162 && inta <= 169)

	    inta += 64;

	if (intb >= 129 && intb <= 137 || intb >= 145 && intb <= 153 || intb 

		>= 162 && intb <= 169)

	    intb += 64;

    } else if (zcode == 218 || zcode == 250) {

	/* ASCII is assumed, on Prime machines - ZCODE is the ASCII code   

          plus 128 of either lower or upper case 'Z'. */

	if (inta >= 225 && inta <= 250) inta += -32;

	if (intb >= 225 && intb <= 250) intb += -32;

    }

    ret_val = inta == intb;

    return ret_val;

} /* lsame_ */