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#define _GNU_SOURCE
/* Because of conditional compilation, this is GNU source only if the C
library is GNU.
*/
#include <stdlib.h>
#include <string.h>
#include "pm_config.h"
#include "pm_c_util.h"
#include "nstring.h"
void
pm_vasprintf(const char ** const resultP,
const char * const format,
va_list varargs) {
char * result;
#if HAVE_VASPRINTF
int rc;
rc = vasprintf(&result, format, varargs);
if (rc < 0)
*resultP = pm_strsol;
else
*resultP = result;
#else
/* We have a big compromise here. To do this right, without a
huge amount of work, we need to go through the variable
arguments twice: once to determine how much memory to allocate,
and once to format the string. On some machines, you can
simply make two copies of the va_list variable in normal C
fashion, but on others you need va_copy, which is a relatively
recent invention. In particular, the simple va_list copy
failed on an AMD64 Gcc Linux system in March 2006.
So instead, we just allocate 4K and truncate or waste as
necessary.
Note that we don't recognize the floating point specifiers (%f, %e, %g)
- we render them as 'f', 'e', and 'g'. It would be too much work to
make this code handle those, just for the few systems on which it runs.
Instead, we have pm_vasprintf_knows_float(), and any caller that cares
enough can avoid using these specifiers where they don't work.
*/
size_t const allocSize = 4096;
result = malloc(allocSize);
if (result == NULL)
*resultP = pm_strsol;
else {
size_t realLen;
pm_vsnprintf(result, allocSize, format, varargs, &realLen);
if (realLen >= allocSize)
strcpy(result + allocSize - 15, "<<<TRUNCATED");
*resultP = result;
}
#endif
}
bool
pm_vasprintf_knows_float(void) {
#if HAVE_VASPRINTF
return true;
#else
return false;
#endif
}
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