/* $Id$ */ | |
/* | |
* Copyright (C)2003-2006 Benny Prijono <benny@prijono.org> | |
* | |
* This program is free software; you can redistribute it and/or modify | |
* it under the terms of the GNU General Public License as published by | |
* the Free Software Foundation; either version 2 of the License, or | |
* (at your option) any later version. | |
* | |
* This program is distributed in the hope that it will be useful, | |
* but WITHOUT ANY WARRANTY; without even the implied warranty of | |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
* GNU General Public License for more details. | |
* | |
* You should have received a copy of the GNU General Public License | |
* along with this program; if not, write to the Free Software | |
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
*/ | |
#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; | |
} |