/** See dropt_vsnprintf. */
int
dropt_snprintf(dropt_char* s, size_t n, const dropt_char* format, ...)
{
int ret;
va_list args;
va_start(args, format);
ret = dropt_vsnprintf(s, n, format, args);
va_end(args);
return ret;
}
/** dropt_vssprintf
*
* Appends a formatted string with vprintf semantics to a
* dropt_stringstream.
*
* PARAMETERS:
* IN/OUT ss : The dropt_stringstream.
* IN format : printf-style format specifier. Must not be NULL.
* IN args : Arguments to insert into the formatted string.
*
* RETURNS:
* The number of characters written to the dropt_stringstream,
* excluding the NUL-terminator.
* Returns a negative value on error.
*/
int
dropt_vssprintf(dropt_stringstream * ss, const dropt_char * format, va_list args)
{
int n;
va_list argsCopy;
assert(ss != NULL);
assert(format != NULL);
va_copy(argsCopy, args);
n = dropt_vsnprintf(NULL, 0, format, argsCopy);
va_end(argsCopy);
if (n > 0) {
size_t available = dropt_ssgetfreespace(ss);
if ((unsigned int) n >= available) {
/* It's possible that newSize < ss->maxSize if
* GROWN_STRINGSTREAM_BUFFER_SIZE overflows, but it should be
* safe since we'll recompute the available space.
*/
size_t newSize = GROWN_STRINGSTREAM_BUFFER_SIZE(ss->maxSize, n);
dropt_ssresize(ss, newSize);
available = dropt_ssgetfreespace(ss);
}
assert(available > 0); /* Space always is reserved for NUL. */
/* snprintf's family of functions return the number of characters
* that would be output with a sufficiently large buffer, excluding
* NUL.
*/
n = dropt_vsnprintf(ss->string + ss->used, available, format, args);
/* We couldn't allocate enough space. */
if ((unsigned int) n >= available) {
n = -1;
}
if (n > 0) {
ss->used += n;
}
}
return n;
}
/** dropt_vasprintf
*
* Allocates a formatted string with vprintf semantics.
*
* PARAMETERS:
* IN format : printf-style format specifier. Must not be NULL.
* IN args : Arguments to insert into the formatted string.
*
* RETURNS:
* The formatted string, which is always NUL-terminated. The caller
* is responsible for calling free() on it when no longer needed.
* Returns NULL on error.
*/
dropt_char *
dropt_vasprintf(const dropt_char * format, va_list args)
{
dropt_char * s = NULL;
int len;
va_list argsCopy;
assert(format != NULL);
va_copy(argsCopy, args);
len = dropt_vsnprintf(NULL, 0, format, argsCopy);
va_end(argsCopy);
if (len >= 0) {
size_t n = len + 1 /* NUL */;
s = dropt_safe_malloc(n, sizeof * s);
if (s != NULL) {
dropt_vsnprintf(s, n, format, args);
}
}
return s;
}
