1 /* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 4 -*- */
2 /* vi: set expandtab shiftwidth=4 tabstop=4: */
3
4 /**
5 * \file modp_ascii.c
6 * <PRE>
7 * MODP_ASCII - Ascii transformations (upper/lower, etc)
8 * http://code.google.com/p/stringencoders/
9 *
10 * Copyright © 2007 Nick Galbreath -- nickg [at] modp [dot] com
11 * All rights reserved.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions are
15 * met:
16 *
17 * Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 *
20 * Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in the
22 * documentation and/or other materials provided with the distribution.
23 *
24 * Neither the name of the modp.com nor the names of its
25 * contributors may be used to endorse or promote products derived from
26 * this software without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
39 *
40 * This is the standard "new" BSD license:
41 * http://www.opensource.org/licenses/bsd-license.php
42 * </PRE>
43 */
44
45 #include <stdint.h>
46 #include "modp_ascii.h"
47 #include "modp_ascii_data.h"
48
modp_toupper_copy(char * dest,const char * str,int len)49 void modp_toupper_copy(char* dest, const char* str, int len)
50 {
51 int i;
52 uint32_t eax, ebx;
53 const uint8_t* ustr = (const uint8_t*) str;
54 const int leftover = len % 4;
55 const int imax = len / 4;
56 const uint32_t* s = (const uint32_t*) str;
57 uint32_t* d = (uint32_t*) dest;
58 for (i = 0; i != imax; ++i) {
59 eax = s[i];
60 /*
61 * This is based on the algorithm by Paul Hsieh
62 * http://www.azillionmonkeys.com/qed/asmexample.html
63 */
64 ebx = (0x7f7f7f7fu & eax) + 0x05050505u;
65 ebx = (0x7f7f7f7fu & ebx) + 0x1a1a1a1au;
66 ebx = ((ebx & ~eax) >> 2) & 0x20202020u;
67 *d++ = eax - ebx;
68 }
69
70 i = imax*4;
71 dest = (char*) d;
72 switch (leftover) {
73 case 3: *dest++ = (char) gsToUpperMap[ustr[i++]];
74 case 2: *dest++ = (char) gsToUpperMap[ustr[i++]];
75 case 1: *dest++ = (char) gsToUpperMap[ustr[i]];
76 case 0: *dest = '\0';
77 }
78 }
79
modp_tolower_copy(char * dest,const char * str,int len)80 void modp_tolower_copy(char* dest, const char* str, int len)
81 {
82 int i;
83 uint32_t eax, ebx;
84 const uint8_t* ustr = (const uint8_t*) str;
85 const int leftover = len % 4;
86 const int imax = len / 4;
87 const uint32_t* s = (const uint32_t*) str;
88 uint32_t* d = (uint32_t*) dest;
89 for (i = 0; i != imax; ++i) {
90 eax = s[i];
91 /*
92 * This is based on the algorithm by Paul Hsieh
93 * http://www.azillionmonkeys.com/qed/asmexample.html
94 */
95 ebx = (0x7f7f7f7fu & eax) + 0x25252525u;
96 ebx = (0x7f7f7f7fu & ebx) + 0x1a1a1a1au;
97 ebx = ((ebx & ~eax) >> 2) & 0x20202020u;
98 *d++ = eax + ebx;
99 }
100
101 i = imax*4;
102 dest = (char*) d;
103 switch (leftover) {
104 case 3: *dest++ = (char) gsToLowerMap[ustr[i++]];
105 case 2: *dest++ = (char) gsToLowerMap[ustr[i++]];
106 case 1: *dest++ = (char) gsToLowerMap[ustr[i]];
107 case 0: *dest = '\0';
108 }
109 }
110
modp_toupper(char * str,int len)111 void modp_toupper(char* str, int len)
112 {
113 modp_toupper_copy(str, str, len);
114 }
115
modp_tolower(char * str,int len)116 void modp_tolower(char* str, int len)
117 {
118 modp_tolower_copy(str,str,len);
119 }
120
modp_toprint_copy(char * dest,const char * str,int len)121 void modp_toprint_copy(char* dest, const char* str, int len)
122 {
123 int i;
124 uint8_t c1,c2,c3,c4;
125
126 const int leftover = len % 4;
127 const int imax = len - leftover;
128 const uint8_t* s = (const uint8_t*) str;
129 for (i = 0; i != imax ; i+=4) {
130 /*
131 * it's important to make these variables
132 * it helps the optimizer to figure out what to do
133 */
134 c1 = s[i]; c2=s[i+1]; c3=s[i+2]; c4=s[i+3];
135 dest[0] = (char) gsToPrintMap[c1];
136 dest[1] = (char) gsToPrintMap[c2];
137 dest[2] = (char) gsToPrintMap[c3];
138 dest[3] = (char) gsToPrintMap[c4];
139 dest += 4;
140 }
141
142 switch (leftover) {
143 case 3: *dest++ = (char) gsToPrintMap[s[i++]];
144 case 2: *dest++ = (char) gsToPrintMap[s[i++]];
145 case 1: *dest++ = (char) gsToPrintMap[s[i]];
146 case 0: *dest = '\0';
147 }
148 }
149
modp_toprint(char * str,int len)150 void modp_toprint(char* str, int len)
151 {
152 modp_toprint_copy(str,str,len);
153 }
154