void reset_buffer(struct safe_buffer* b)
{
- if (b && b->buffer != NULL)
- b->buffer[0] = '\0';
+ if (b && b->buffer != NULL) {
+ memset(b->buffer, 0, b->bufsize);
+ b->buf_end = b->buffer;
+ b->buflen = 0;
+ }
}
void cleanup_buffer(struct safe_buffer *b)
if (b && b->buffer == NULL) {
b->buffer = (char *)malloc(INITIAL_BUF_SIZE);
if (b->buffer) {
- b->buffer[0] = '\0';
b->bufsize = INITIAL_BUF_SIZE;
+ memset(b->buffer, 0, b->bufsize);
+ b->buf_end = b->buffer;
+ b->buflen = 0;
if (b->cleanup_func && atexit(b->cleanup_func) != 0) {
fprintf(stderr, _("Could not register buffer cleanup function"));
fprintf(stderr, "\n");
}
}
+void grow_buffer(struct safe_buffer *b)
+{
+ char* new_buffer;
+ size_t old_size = b->bufsize;
+ b->bufsize *= 2;
+ new_buffer = realloc(b->buffer, b->bufsize);
+ if (new_buffer) {
+ b->buffer = new_buffer;
+ memset(b->buffer + old_size, 0, b->bufsize - old_size);
+ b->buf_end = b->buffer + b->buflen;
+ }
+ else
+ b->buffer = NULL;
+}
+
int safe_buf_vappend(struct safe_buffer *b, const char *s, va_list ap)
{
int res = 0;
- int len;
init_buffer(b);
if (b && b->buffer) {
- len = strlen(b->buffer);
while (1) {
- char *buf_ptr = b->buffer + len;
- int rest_size = b->bufsize - len;
+ int rest_size = b->bufsize - b->buflen;
#if HAVE_VSNPRINTF
- res = vsnprintf(buf_ptr, rest_size, s, ap);
+ res = vsnprintf(b->buf_end, rest_size, s, ap);
if (res > -1 && res < rest_size) {
+ b->buf_end = b->buf_end + res;
+ b->buflen = b->buflen + res;
break;
}
- else {
- b->bufsize *= 2;
- b->buffer = realloc(b->buffer, b->bufsize);
+ else {
+ grow_buffer(b);
}
#else /* not HAVE_VSNPRINTF */
# if HAVE_VSPRINTF
# warning "Using VSPRINTF. Buffer overflow could happen!"
- vsprintf(buf_ptr, s, ap);
+ res = vsprintf(b->buf_end, s, ap);
+ b->buf_end = b->buf_end + res;
+ b->buflen = b->buflen + res;
break;
# else /* not HAVE_VPRINTF */
# error "Your standard library has neither vsnprintf nor vsprintf defined. One of them is required!"