page ,132 title strnicmp - compare n chars of strings, ignore case ;*** ;strnicmp.asm - compare n chars of strings, ignoring case ; ; Copyright (c) 1985-1991, Microsoft Corporation. All rights reserved. ; ;Purpose: ; defines _strnicmp() - Compares at most n characters of two strings, ; without regard to case. ; ;Revision History: ; 04-04-85 RN initial version ; 07-11-85 TC zeroed cx, to allow correct return value if not equal ; 05-18-88 SJM Add model-independent (large model) ifdef ; 08-04-88 SJM convert to cruntime/ add 32-bit support ; 08-23-88 JCR 386 cleanup and improved return value sequence ; 10-26-88 JCR General cleanup for 386-only code ; 03-23-90 GJF Changed to _stdcall. Also, fixed the copyright. ; 01-18-91 GJF ANSI naming. ; 05-10-91 GJF Back to _cdecl, sigh... ; ;******************************************************************************* .xlist include cruntime.inc .list page ;*** ;int _strnicmp(first, last, count) - compares count char of strings, ignore case ; ;Purpose: ; Compare the two strings for lexical order. Stops the comparison ; when the following occurs: (1) strings differ, (2) the end of the ; strings is reached, or (3) count characters have been compared. ; For the purposes of the comparison, upper case characters are ; converted to lower case. ; ; Algorithm: ; int ; _strncmpi (first, last, count) ; char *first, *last; ; unsigned int count; ; { ; int f,l; ; int result = 0; ; ; if (count) { ; do { ; f = tolower(*first); ; l = tolower(*last); ; first++; ; last++; ; } while (--count && f && l && f == l); ; result = f - l; ; } ; return(result); ; } ; ;Entry: ; char *first, *last - strings to compare ; unsigned count - maximum number of characters to compare ; ;Exit: ; returns <0 if first < last ; returns 0 if first == last ; returns >0 if first > last ; ;Uses: ; ;Exceptions: ; ;******************************************************************************* CODESEG public _strnicmp _strnicmp proc \ uses edi esi ebx, \ first:ptr byte, \ last:ptr byte, \ count:IWORD mov esi,[first] ; si = first string mov edi,[last] ; di = last string mov ecx,[count] ; cx = byte count jecxz short toend ; if count=0 mov bh,'A' mov bl,'Z' mov dh,'a'-'A' ; add to cap to make lower lupe: mov ah,[esi] ; *first mov al,[edi] ; *last or ah,ah ; see if *first is null jz short eject ; jump if so or al,al ; see if *last is null jz short eject ; jump if so inc esi ; first++ inc edi ; last++ cmp ah,bh ; 'A' jb short skip1 cmp ah,bl ; 'Z' ja short skip1 add ah,dh ; make lower case skip1: cmp al,bh ; 'A' jb short skip2 cmp al,bl ; 'Z' ja short skip2 add al,dh ; make lower case skip2: cmp ah,al ; *first == *last ?? jne short differ loop lupe eject: xor ecx,ecx cmp ah,al ; compare the (possibly) differing bytes je short toend ; both zero; return 0 differ: mov ecx,-1 ; assume last is bigger (* can't use 'or' *) jb short toend ; last is, in fact, bigger (return -1) neg ecx ; first is bigger (return 1) toend: mov eax,ecx ifdef _STDCALL_ ret 2*DPSIZE + ISIZE ; _stdcall return else ret ; _cdecl return endif _strnicmp endp end