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/*
Copyright (C) 2002 Vladimir Oleynik <dzo@simtreas.ru>
*/
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#ifdef TEST
extern void *xrealloc(void *p, size_t size);
#else
#include "libbb.h" /* busybox source */
#endif
/* Exchange glibc vasprintf - minimize allocate memory version */
/* libc5 and uclibc have not vasprintf function */
void bb_vasprintf(char **string_ptr, const char *format, va_list args)
{
int bs = 128;
char stack_buff[128];
char *buff = stack_buff;
int done;
/* two or more loop, first - calculate memory size only */
while(1) {
done = vsnprintf (buff, bs, format, args);
/* Different libc have different interpretation vsnprintf returned value */
if(done >= 0) {
if(done < bs && buff != stack_buff) {
/* allocated */
*string_ptr = buff;
return;
} else {
/* true calculate memory size */
bs = done+1;
}
} else {
/*
* Old libc. Incrementaly test.
* Exact not minimize allocate memory.
*/
bs += 128;
}
buff = xrealloc((buff == stack_buff ? NULL : buff), bs);
}
}
void bb_asprintf(char **string_ptr, const char *format, ...)
{
va_list p;
va_start(p, format);
bb_vasprintf(string_ptr, format, p);
va_end(p);
}
#ifdef TEST
int main(int argc, char **argv)
{
char *out_buf;
char big_buf[200];
int i;
bb_asprintf(&out_buf, "Hi!\nargc=%d argv[0]=%s\n", argc, argv[0]);
printf(out_buf);
free(out_buf);
for(i=0; i < sizeof(big_buf)-1; i++)
big_buf[i]='x';
big_buf[i]=0;
bb_asprintf(&out_buf, "Test Big\n%s\n", big_buf);
printf(out_buf);
free(out_buf);
return 0;
}
void *xrealloc(void *p, size_t size)
{
void *p2 = realloc(p, size);
if(p2==0) {
fprintf(stderr, "TEST: memory_exhausted\n");
exit(1);
}
return p2;
}
#endif
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