1 //===========================================================================
5 // ANSI standard strlen() routine
7 //===========================================================================
8 //####ECOSGPLCOPYRIGHTBEGIN####
9 // -------------------------------------------
10 // This file is part of eCos, the Embedded Configurable Operating System.
11 // Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
13 // eCos is free software; you can redistribute it and/or modify it under
14 // the terms of the GNU General Public License as published by the Free
15 // Software Foundation; either version 2 or (at your option) any later version.
17 // eCos is distributed in the hope that it will be useful, but WITHOUT ANY
18 // WARRANTY; without even the implied warranty of MERCHANTABILITY or
19 // FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
22 // You should have received a copy of the GNU General Public License along
23 // with eCos; if not, write to the Free Software Foundation, Inc.,
24 // 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
26 // As a special exception, if other files instantiate templates or use macros
27 // or inline functions from this file, or you compile this file and link it
28 // with other works to produce a work based on this file, this file does not
29 // by itself cause the resulting work to be covered by the GNU General Public
30 // License. However the source code for this file must still be made available
31 // in accordance with section (3) of the GNU General Public License.
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34 // this file might be covered by the GNU General Public License.
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37 // at http://sources.redhat.com/ecos/ecos-license/
38 // -------------------------------------------
39 //####ECOSGPLCOPYRIGHTEND####
40 //===========================================================================
41 //#####DESCRIPTIONBEGIN####
43 // Author(s): jlarmour
50 //####DESCRIPTIONEND####
52 //===========================================================================
56 #include <pkgconf/libc_string.h> // Configuration header
60 #include <cyg/infra/cyg_type.h> // Common type definitions
61 #include <cyg/infra/cyg_trac.h> // Tracing support
62 #include <cyg/infra/cyg_ass.h> // Assertion support
63 #include <string.h> // Header for this file
64 #include <stddef.h> // Compiler definitions such as size_t, NULL etc.
65 #include <cyg/libc/string/stringsupp.hxx> // Useful string function support and
71 strlen( const char *s ) CYGBLD_ATTRIB_WEAK_ALIAS(__strlen);
76 __strlen( const char *s )
80 CYG_REPORT_FUNCNAMETYPE( "__strlen", "returning length %d" );
81 CYG_REPORT_FUNCARG1( "s=%08x", s );
83 CYG_CHECK_DATA_PTR( s, "s is not a valid pointer!" );
85 #if defined(CYGIMP_LIBC_STRING_PREFER_SMALL_TO_FAST) || defined(__OPTIMIZE_SIZE__)
86 const char *start = s;
93 CYG_REPORT_RETVAL( retval );
99 const char *start = s;
100 CYG_WORD *aligned_addr;
102 if (CYG_LIBC_STR_UNALIGNED (s))
108 CYG_REPORT_RETVAL( retval );
113 // If the string is word-aligned, we can check for the presence of
114 // a null in each word-sized block.
116 aligned_addr = (CYG_WORD *)s;
117 while (!CYG_LIBC_STR_DETECTNULL (*aligned_addr))
120 // Once a null is detected, we check each byte in that block for a
121 // precise position of the null.
122 s = (char*)aligned_addr;
127 CYG_REPORT_RETVAL( retval );
130 #endif // not defined(CYGIMP_LIBC_STRING_PREFER_SMALL_TO_FAST) ||
131 // defined(__OPTIMIZE_SIZE__)