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/branches/tracing/kernel/generic/src/printf/vsnprintf.c
26,7 → 26,7
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
 
/** @addtogroup generic
/** @addtogroup generic
* @{
*/
/** @file
34,62 → 34,146
 
#include <print.h>
#include <printf/printf_core.h>
#include <string.h>
#include <memstr.h>
#include <errno.h>
 
struct vsnprintf_data {
size_t size; /* total space for string */
size_t len; /* count of currently used characters */
char *string; /* destination string */
};
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 string to given buffer.
* Write at most data->size 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
* number of really printed characters but size of the input string. Number of really used characters
* is stored in data->len.
* @param str source string to print
* @param count size of source string
* @param data structure with destination string, counter of used space and total string size.
* @return number of characters to print (not characters really printed!)
*
* 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 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 characters to print (not characters actually
* printed).
*
*/
static int vsnprintf_write(const char *str, size_t count, struct vsnprintf_data *data)
static int vsnprintf_str_write(const char *str, size_t size, vsnprintf_data_t *data)
{
size_t i;
i = data->size - data->len;
 
if (i == 0) {
return count;
}
size_t left = data->size - data->len;
if (i == 1) {
/* We have only one free byte left in buffer => write there trailing zero */
data->string[data->size - 1] = 0;
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 count;
return ((int) size);
}
if (i <= count) {
/* We have not enought space for whole string with the trailing zero => print only a part of string */
memcpy((void *)(data->string + data->len), (void *)str, i - 1);
data->string[data->size - 1] = 0;
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 = str_decode(str, &index, size);
if (chr_encode(uc, data->dst, &data->len, data->size - 1) != EOK)
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 wide 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 wide 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 wide characters to print (not characters actually
* printed).
*
*/
static int vsnprintf_wstr_write(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 count;
return ((int) size);
}
if (chr_encode(str[index], data->dst, &data->len, data->size - 1) != EOK)
break;
index++;
}
/* Buffer is big enought to print whole string */
memcpy((void *)(data->string + data->len), (void *)str, count);
data->len += count;
/* Put trailing zero at end, but not count it into data->len so it could be rewritten next time */
data->string[data->len] = 0;
 
return count;
/* 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)
{
struct vsnprintf_data data = {size, 0, str};
struct printf_spec ps = {(int(*)(void *, size_t, void *))vsnprintf_write, &data};
 
vsnprintf_data_t data = {
size,
0,
str
};
printf_spec_t ps = {
(int(*) (const char *, size_t, void *)) vsnprintf_str_write,
(int(*) (const wchar_t *, size_t, void *)) vsnprintf_wstr_write,
&data
};
/* Print 0 at end of string - fix the case that nothing will be printed */
if (size > 0)
str[0] = 0;