diff options
Diffstat (limited to 'pjlib/src/pj/fifobuf.c')
| -rw-r--r-- | pjlib/src/pj/fifobuf.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/pjlib/src/pj/fifobuf.c b/pjlib/src/pj/fifobuf.c new file mode 100644 index 00000000..d0b41a15 --- /dev/null +++ b/pjlib/src/pj/fifobuf.c @@ -0,0 +1,182 @@ +/* $Header: /pjproject-0.3/pjlib/src/pj/fifobuf.c 4 9/17/05 10:37a Bennylp $ */
+/* $Log: /pjproject-0.3/pjlib/src/pj/fifobuf.c $
+ *
+ * 4 9/17/05 10:37a Bennylp
+ * Major reorganization towards version 0.3.
+ *
+ */
+#include <pj/fifobuf.h>
+#include <pj/log.h>
+#include <pj/assert.h>
+#include <pj/os.h>
+
+#define THIS_FILE "fifobuf"
+
+#define SZ sizeof(unsigned)
+
+PJ_DEF(void)
+pj_fifobuf_init (pj_fifobuf_t *fifobuf, void *buffer, unsigned size)
+{
+ PJ_CHECK_STACK();
+
+ PJ_LOG(6, (THIS_FILE,
+ "fifobuf_init fifobuf=%p buffer=%p, size=%d",
+ fifobuf, buffer, size));
+
+ fifobuf->first = buffer;
+ fifobuf->last = fifobuf->first + size;
+ fifobuf->ubegin = fifobuf->uend = fifobuf->first;
+ fifobuf->full = 0;
+}
+
+PJ_DEF(unsigned)
+pj_fifobuf_max_size (pj_fifobuf_t *fifobuf)
+{
+ unsigned s1, s2;
+
+ PJ_CHECK_STACK();
+
+ if (fifobuf->uend >= fifobuf->ubegin) {
+ s1 = fifobuf->last - fifobuf->uend;
+ s2 = fifobuf->ubegin - fifobuf->first;
+ } else {
+ s1 = s2 = fifobuf->ubegin - fifobuf->uend;
+ }
+
+ return s1<s2 ? s2 : s1;
+}
+
+PJ_DEF(void*)
+pj_fifobuf_alloc (pj_fifobuf_t *fifobuf, unsigned size)
+{
+ unsigned available;
+ char *start;
+
+ PJ_CHECK_STACK();
+
+ if (fifobuf->full) {
+ PJ_LOG(6, (THIS_FILE,
+ "fifobuf_alloc fifobuf=%p, size=%d: full!",
+ fifobuf, size));
+ return NULL;
+ }
+
+ /* try to allocate from the end part of the fifo */
+ if (fifobuf->uend >= fifobuf->ubegin) {
+ available = fifobuf->last - fifobuf->uend;
+ if (available >= size+SZ) {
+ char *ptr = fifobuf->uend;
+ fifobuf->uend += (size+SZ);
+ if (fifobuf->uend == fifobuf->last)
+ fifobuf->uend = fifobuf->first;
+ if (fifobuf->uend == fifobuf->ubegin)
+ fifobuf->full = 1;
+ *(unsigned*)ptr = size+SZ;
+ ptr += SZ;
+
+ PJ_LOG(6, (THIS_FILE,
+ "fifobuf_alloc fifobuf=%p, size=%d: returning %p, p1=%p, p2=%p",
+ fifobuf, size, ptr, fifobuf->ubegin, fifobuf->uend));
+ return ptr;
+ }
+ }
+
+ /* try to allocate from the start part of the fifo */
+ start = (fifobuf->uend <= fifobuf->ubegin) ? fifobuf->uend : fifobuf->first;
+ available = fifobuf->ubegin - start;
+ if (available >= size+SZ) {
+ char *ptr = start;
+ fifobuf->uend = start + size + SZ;
+ if (fifobuf->uend == fifobuf->ubegin)
+ fifobuf->full = 1;
+ *(unsigned*)ptr = size+SZ;
+ ptr += SZ;
+
+ PJ_LOG(6, (THIS_FILE,
+ "fifobuf_alloc fifobuf=%p, size=%d: returning %p, p1=%p, p2=%p",
+ fifobuf, size, ptr, fifobuf->ubegin, fifobuf->uend));
+ return ptr;
+ }
+
+ PJ_LOG(6, (THIS_FILE,
+ "fifobuf_alloc fifobuf=%p, size=%d: no space left! p1=%p, p2=%p",
+ fifobuf, size, fifobuf->ubegin, fifobuf->uend));
+ return NULL;
+}
+
+PJ_DEF(pj_status_t)
+pj_fifobuf_unalloc (pj_fifobuf_t *fifobuf, void *buf)
+{
+ char *ptr = buf;
+ char *endptr;
+ unsigned sz;
+
+ PJ_CHECK_STACK();
+
+ ptr -= SZ;
+ sz = *(unsigned*)ptr;
+
+ endptr = fifobuf->uend;
+ if (endptr == fifobuf->first)
+ endptr = fifobuf->last;
+
+ if (ptr+sz != endptr) {
+ pj_assert(!"Invalid pointer to undo alloc");
+ return -1;
+ }
+
+ fifobuf->uend = ptr;
+ fifobuf->full = 0;
+
+ PJ_LOG(6, (THIS_FILE,
+ "fifobuf_unalloc fifobuf=%p, ptr=%p, size=%d, p1=%p, p2=%p",
+ fifobuf, buf, sz, fifobuf->ubegin, fifobuf->uend));
+
+ return 0;
+}
+
+PJ_DEF(pj_status_t)
+pj_fifobuf_free (pj_fifobuf_t *fifobuf, void *buf)
+{
+ char *ptr = buf;
+ char *end;
+ unsigned sz;
+
+ PJ_CHECK_STACK();
+
+ ptr -= SZ;
+ if (ptr < fifobuf->first || ptr >= fifobuf->last) {
+ pj_assert(!"Invalid pointer to free");
+ return -1;
+ }
+
+ if (ptr != fifobuf->ubegin && ptr != fifobuf->first) {
+ pj_assert(!"Invalid free() sequence!");
+ return -1;
+ }
+
+ end = (fifobuf->uend > fifobuf->ubegin) ? fifobuf->uend : fifobuf->last;
+ sz = *(unsigned*)ptr;
+ if (ptr+sz > end) {
+ pj_assert(!"Invalid size!");
+ return -1;
+ }
+
+ fifobuf->ubegin = ptr + sz;
+
+ /* Rollover */
+ if (fifobuf->ubegin == fifobuf->last)
+ fifobuf->ubegin = fifobuf->first;
+
+ /* Reset if fifobuf is empty */
+ if (fifobuf->ubegin == fifobuf->uend)
+ fifobuf->ubegin = fifobuf->uend = fifobuf->first;
+
+ fifobuf->full = 0;
+
+ PJ_LOG(6, (THIS_FILE,
+ "fifobuf_free fifobuf=%p, ptr=%p, size=%d, p1=%p, p2=%p",
+ fifobuf, buf, sz, fifobuf->ubegin, fifobuf->uend));
+
+ return 0;
+}
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