WebSVN – HelenOS – Diff – /trunk/kernel/generic/src/printf/vsnprintf.c


/*
 * Copyright (c) 2006 Josef Cejka
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
/** @addtogroup generic
 * @{
 */
/** @file
 */
 
#include <print.h>
#include <printf/printf_core.h>
#include <string.h>
#include <memstr.h>
 
typedef struct {
    size_t size;    /* Total size of the buffer (in bytes) */
    size_t len;     /* Number of already used bytes */
    char *dst;      /* Destination */
} vsnprintf_data_t;
 
/** Write UTF-8 string to given buffer.
 *
 * Write at most data->size plain characters including trailing zero.
 * According to C99, snprintf() has to return number of characters that
 * would have been written if enough space had been available. Hence
 * the return value is not the number of actually printed characters
 * but size of the input string.
 *
 * @param str  Source UTF-8 string to print.
 * @param size Number of plain characters in str.
 * @param data Structure describing destination string, counter
 *             of used space and total string size.
 *
 * @return Number of UTF-8 characters to print (not characters actually
 *         printed).
 *
 */
static int vsnprintf_write_utf8(const char *str, size_t size, vsnprintf_data_t *data)
{
    size_t left = data->size - data->len;
   
    if (left == 0)
        return ((int) size);
   
    if (left == 1) {
        /* We have only one free byte left in buffer
         * -> store trailing zero
         */
        data->dst[data->size - 1] = 0;
        data->len = data->size;
        return ((int) size);
    }
   
    if (left <= size) {
        /* We do not have enough space for the whole string
         * with the trailing zero => print only a part
         * of string
         */
        index_t index = 0;
       
        while (index < size) {
            wchar_t uc = chr_decode(str, &index, size);
 
            if (!chr_encode(uc, data->dst, &data->len, data->size - 1))
                break;
        }
       
        /* Put trailing zero at end, but not count it
         * into data->len so it could be rewritten next time
         */
        data->dst[data->len] = 0;
       
        return ((int) size);
    }
   
    /* Buffer is big enought to print the whole string */
    memcpy((void *)(data->dst + data->len), (void *) str, size);
    data->len += size;
   
    /* Put trailing zero at end, but not count it
     * into data->len so it could be rewritten next time
     */
    data->dst[data->len] = 0;
   
    return ((int) size);
}
 
/** Write UTF-32 string to given buffer.
 *
 * Write at most data->size plain characters including trailing zero.
 * According to C99, snprintf() has to return number of characters that
 * would have been written if enough space had been available. Hence
 * the return value is not the number of actually printed characters
 * but size of the input string.
 *
 * @param str  Source UTF-32 string to print.
 * @param size Number of bytes in str.
 * @param data Structure describing destination string, counter
 *             of used space and total string size.
 *
 * @return Number of UTF-8 characters to print (not characters actually
 *         printed).
 *
 */
static int vsnprintf_write_utf32(const wchar_t *str, size_t size, vsnprintf_data_t *data)
{
    index_t index = 0;
   
    while (index < (size / sizeof(wchar_t))) {
        size_t left = data->size - data->len;
       
        if (left == 0)
            return ((int) size);
       
        if (left == 1) {
            /* We have only one free byte left in buffer
             * -> store trailing zero
             */
            data->dst[data->size - 1] = 0;
            data->len = data->size;
            return ((int) size);
        }
       
        if (!chr_encode(str[index], data->dst, &data->len, data->size - 1))
            break;
       
        index++;
    }
   
    /* Put trailing zero at end, but not count it
     * into data->len so it could be rewritten next time
     */
    data->dst[data->len] = 0;
   
    return ((int) size);
}
 
int vsnprintf(char *str, size_t size, const char *fmt, va_list ap)
{
    vsnprintf_data_t data = {
        size,
        0,
        str
    };
    printf_spec_t ps = {
        (int(*) (const char *, size_t, void *)) vsnprintf_write_utf8,
        (int(*) (const wchar_t *, size_t, void *)) vsnprintf_write_utf32,
        &data
    };
   
    /* Print 0 at end of string - fix the case that nothing will be printed */
    if (size > 0)
        str[0] = 0;
   
    /* vsnprintf_write ensures that str will be terminated by zero. */
    return printf_core(fmt, &ps, ap);
}
 
/** @}
 */
 

Subversion Repositories HelenOS

(root)/trunk/kernel/generic/src/printf/vsnprintf.c @ 2064 – Rev 4200 → 4206

Rev 4200		Rev 4206
1	/*	1	/*
2	* Copyright (c) 2006 Josef Cejka	2	* Copyright (c) 2006 Josef Cejka
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	13	* documentation and/or other materials provided with the distribution.
14	* - The name of the author may not be used to endorse or promote products	14	* - The name of the author may not be used to endorse or promote products
15	* derived from this software without specific prior written permission.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	/** @addtogroup generic	29	/** @addtogroup generic
30	* @{	30	* @{
31	*/	31	*/
32	/** @file	32	/** @file
33	*/	33	*/
34		34
35	#include <print.h>	35	#include <print.h>
36	#include <printf/printf_core.h>	36	#include <printf/printf_core.h>
37	#include <string.h>	37	#include <string.h>
38	#include <memstr.h>	38	#include <memstr.h>
39		39
40	typedef struct {	40	typedef struct {
41	size_t size; /* Total size of the buffer (in bytes) */	41	size_t size; /* Total size of the buffer (in bytes) */
42	size_t len; /* Number of already used bytes */	42	size_t len; /* Number of already used bytes */
43	char dst; / Destination */	43	char dst; / Destination */
44	} vsnprintf_data_t;	44	} vsnprintf_data_t;
45		45
46	/** Write UTF-8 string to given buffer.	46	/** Write UTF-8 string to given buffer.
47	*	47	*
48	* Write at most data->size plain characters including trailing zero.	48	* Write at most data->size plain characters including trailing zero.
49	* According to C99, snprintf() has to return number of characters that	49	* According to C99, snprintf() has to return number of characters that
50	* would have been written if enough space had been available. Hence	50	* would have been written if enough space had been available. Hence
51	* the return value is not the number of actually printed characters	51	* the return value is not the number of actually printed characters
52	* but size of the input string.	52	* but size of the input string.
53	*	53	*
54	* @param str Source UTF-8 string to print.	54	* @param str Source UTF-8 string to print.
55	* @param size Number of plain characters in str.	55	* @param size Number of plain characters in str.
56	* @param data Structure describing destination string, counter	56	* @param data Structure describing destination string, counter
57	* of used space and total string size.	57	* of used space and total string size.
58	*	58	*
59	* @return Number of UTF-8 characters to print (not characters actually	59	* @return Number of UTF-8 characters to print (not characters actually
60	* printed).	60	* printed).
61	*	61	*
62	*/	62	*/
63	static int vsnprintf_write_utf8(const char str, size_t size, vsnprintf_data_t data)	63	static int vsnprintf_write_utf8(const char str, size_t size, vsnprintf_data_t data)
64	{	64	{
65	size_t left = data->size - data->len;	65	size_t left = data->size - data->len;
66		66
67	if (left == 0)	67	if (left == 0)
68	return ((int) size);	68	return ((int) size);
69		69
70	if (left == 1) {	70	if (left == 1) {
71	/* We have only one free byte left in buffer	71	/* We have only one free byte left in buffer
72	* -> store trailing zero	72	* -> store trailing zero
73	*/	73	*/
74	data->dst[data->size - 1] = 0;	74	data->dst[data->size - 1] = 0;
75	data->len = data->size;	75	data->len = data->size;
76	return ((int) size);	76	return ((int) size);
77	}	77	}
78		78
79	if (left <= size) {	79	if (left <= size) {
80	/* We have not enought space for whole string	80	/* We do not have enough space for the whole string
81	* with the trailing zero => print only a part	81	* with the trailing zero => print only a part
82	* of string	82	* of string
83	*/	83	*/
84	index_t index = 0;	84	index_t index = 0;
85		85
86	while (index < size) {	86	while (index < size) {
87	wchar_t uc = chr_decode(str, &index, size);	87	wchar_t uc = chr_decode(str, &index, size);
88		88
89	if (!chr_encode(uc, data->dst, &data->len, data->size - 1))	89	if (!chr_encode(uc, data->dst, &data->len, data->size - 1))
90	break;	90	break;
91	}	91	}
92		92
93	/* Put trailing zero at end, but not count it	93	/* Put trailing zero at end, but not count it
94	* into data->len so it could be rewritten next time	94	* into data->len so it could be rewritten next time
95	*/	95	*/
96	data->dst[data->len] = 0;	96	data->dst[data->len] = 0;
97		97
98	return ((int) size);	98	return ((int) size);
99	}	99	}
100		100
101	/* Buffer is big enought to print the whole string */	101	/* Buffer is big enought to print the whole string */
102	memcpy((void )(data->dst + data->len), (void ) str, size);	102	memcpy((void )(data->dst + data->len), (void ) str, size);
103	data->len += size;	103	data->len += size;
104		104
105	/* Put trailing zero at end, but not count it	105	/* Put trailing zero at end, but not count it
106	* into data->len so it could be rewritten next time	106	* into data->len so it could be rewritten next time
107	*/	107	*/
108	data->dst[data->len] = 0;	108	data->dst[data->len] = 0;
109		109
110	return ((int) size);	110	return ((int) size);
111	}	111	}
112		112
113	/** Write UTF-32 string to given buffer.	113	/** Write UTF-32 string to given buffer.
114	*	114	*
115	* Write at most data->size plain characters including trailing zero.	115	* Write at most data->size plain characters including trailing zero.
116	* According to C99, snprintf() has to return number of characters that	116	* According to C99, snprintf() has to return number of characters that
117	* would have been written if enough space had been available. Hence	117	* would have been written if enough space had been available. Hence
118	* the return value is not the number of actually printed characters	118	* the return value is not the number of actually printed characters
119	* but size of the input string.	119	* but size of the input string.
120	*	120	*
121	* @param str Source UTF-32 string to print.	121	* @param str Source UTF-32 string to print.
122	* @param size Number of bytes in str.	122	* @param size Number of bytes in str.
123	* @param data Structure describing destination string, counter	123	* @param data Structure describing destination string, counter
124	* of used space and total string size.	124	* of used space and total string size.
125	*	125	*
126	* @return Number of UTF-8 characters to print (not characters actually	126	* @return Number of UTF-8 characters to print (not characters actually
127	* printed).	127	* printed).
128	*	128	*
129	*/	129	*/
130	static int vsnprintf_write_utf32(const wchar_t str, size_t size, vsnprintf_data_t data)	130	static int vsnprintf_write_utf32(const wchar_t str, size_t size, vsnprintf_data_t data)
131	{	131	{
132	index_t index = 0;	132	index_t index = 0;
133		133
134	while (index < (size / sizeof(wchar_t))) {	134	while (index < (size / sizeof(wchar_t))) {
135	size_t left = data->size - data->len;	135	size_t left = data->size - data->len;
136		136
137	if (left == 0)	137	if (left == 0)
138	return ((int) size);	138	return ((int) size);
139		139
140	if (left == 1) {	140	if (left == 1) {
141	/* We have only one free byte left in buffer	141	/* We have only one free byte left in buffer
142	* -> store trailing zero	142	* -> store trailing zero
143	*/	143	*/
144	data->dst[data->size - 1] = 0;	144	data->dst[data->size - 1] = 0;
145	data->len = data->size;	145	data->len = data->size;
146	return ((int) size);	146	return ((int) size);
147	}	147	}
148		148
149	if (!chr_encode(str[index], data->dst, &data->len, data->size - 1))	149	if (!chr_encode(str[index], data->dst, &data->len, data->size - 1))
150	break;	150	break;
151		151
152	index++;	152	index++;
153	}	153	}
154		154
155	/* Put trailing zero at end, but not count it	155	/* Put trailing zero at end, but not count it
156	* into data->len so it could be rewritten next time	156	* into data->len so it could be rewritten next time
157	*/	157	*/
158	data->dst[data->len] = 0;	158	data->dst[data->len] = 0;
159		159
160	return ((int) size);	160	return ((int) size);
161	}	161	}
162		162
163	int vsnprintf(char str, size_t size, const char fmt, va_list ap)	163	int vsnprintf(char str, size_t size, const char fmt, va_list ap)
164	{	164	{
165	vsnprintf_data_t data = {	165	vsnprintf_data_t data = {
166	size,	166	size,
167	0,	167	0,
168	str	168	str
169	};	169	};
170	printf_spec_t ps = {	170	printf_spec_t ps = {
171	(int() (const char , size_t, void *)) vsnprintf_write_utf8,	171	(int() (const char , size_t, void *)) vsnprintf_write_utf8,
172	(int() (const wchar_t , size_t, void *)) vsnprintf_write_utf32,	172	(int() (const wchar_t , size_t, void *)) vsnprintf_write_utf32,
173	&data	173	&data
174	};	174	};
175		175
176	/* Print 0 at end of string - fix the case that nothing will be printed */	176	/* Print 0 at end of string - fix the case that nothing will be printed */
177	if (size > 0)	177	if (size > 0)
178	str[0] = 0;	178	str[0] = 0;
179		179
180	/* vsnprintf_write ensures that str will be terminated by zero. */	180	/* vsnprintf_write ensures that str will be terminated by zero. */
181	return printf_core(fmt, &ps, ap);	181	return printf_core(fmt, &ps, ap);
182	}	182	}
183		183
184	/** @}	184	/** @}
185	*/	185	*/
186		186