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5083 avoid undefined order of operations in assignments


1766                 rb_head->put_idx = 0;
1767                 rb_head->get_idx = 0;
1768                 rb_head->size = 0;
1769                 rb_head->state = SGHSC_RB_EMPTY;
1770         }
1771 }
1772 
1773 /*
1774  * sghsc_rb_put()
1775  *      Insert an event info into the event ring buffer.
1776  * Returns DDI_FAILURE if the buffer is full, DDI_SUCCESS otherwise
1777  */
1778 static int
1779 sghsc_rb_put(sghsc_rb_head_t *rb_head, sghsc_event_t *event)
1780 {
1781         if (rb_head->state == SGHSC_RB_FULL)
1782                 return (DDI_FAILURE);
1783 
1784         rb_head->buf[rb_head->put_idx] = *event;
1785 
1786         rb_head->put_idx = ++rb_head->put_idx & (rb_head->size - 1);
1787 
1788         if (rb_head->put_idx == rb_head->get_idx)
1789                 rb_head->state = SGHSC_RB_FULL;
1790         else
1791                 rb_head->state = SGHSC_RB_FLOAT;
1792 
1793         return (DDI_SUCCESS);
1794 }
1795 /*
1796  * sghsc_rb_get()
1797  *      Remove an event info from the event  ring buffer.
1798  * Returns DDI_FAILURE if the buffer is empty, DDI_SUCCESS otherwise.
1799  */
1800 static int
1801 sghsc_rb_get(sghsc_rb_head_t *rb_head, sghsc_event_t *event)
1802 {
1803 
1804         if (rb_head->state == SGHSC_RB_EMPTY)
1805                 return (DDI_FAILURE);
1806 
1807         *event = rb_head->buf[rb_head->get_idx];
1808 
1809         rb_head->get_idx = ++rb_head->get_idx & (rb_head->size - 1);
1810 
1811         if (rb_head->get_idx == rb_head->put_idx)
1812                 rb_head->state = SGHSC_RB_EMPTY;
1813         else
1814                 rb_head->state = SGHSC_RB_FLOAT;
1815 
1816         return (DDI_SUCCESS);
1817 }



1766                 rb_head->put_idx = 0;
1767                 rb_head->get_idx = 0;
1768                 rb_head->size = 0;
1769                 rb_head->state = SGHSC_RB_EMPTY;
1770         }
1771 }
1772 
1773 /*
1774  * sghsc_rb_put()
1775  *      Insert an event info into the event ring buffer.
1776  * Returns DDI_FAILURE if the buffer is full, DDI_SUCCESS otherwise
1777  */
1778 static int
1779 sghsc_rb_put(sghsc_rb_head_t *rb_head, sghsc_event_t *event)
1780 {
1781         if (rb_head->state == SGHSC_RB_FULL)
1782                 return (DDI_FAILURE);
1783 
1784         rb_head->buf[rb_head->put_idx] = *event;
1785 
1786         rb_head->put_idx = (rb_head->put_idx + 1) & (rb_head->size - 1);
1787 
1788         if (rb_head->put_idx == rb_head->get_idx)
1789                 rb_head->state = SGHSC_RB_FULL;
1790         else
1791                 rb_head->state = SGHSC_RB_FLOAT;
1792 
1793         return (DDI_SUCCESS);
1794 }
1795 /*
1796  * sghsc_rb_get()
1797  *      Remove an event info from the event  ring buffer.
1798  * Returns DDI_FAILURE if the buffer is empty, DDI_SUCCESS otherwise.
1799  */
1800 static int
1801 sghsc_rb_get(sghsc_rb_head_t *rb_head, sghsc_event_t *event)
1802 {
1803 
1804         if (rb_head->state == SGHSC_RB_EMPTY)
1805                 return (DDI_FAILURE);
1806 
1807         *event = rb_head->buf[rb_head->get_idx];
1808 
1809         rb_head->get_idx = (rb_head->get_idx + 1) & (rb_head->size - 1);
1810 
1811         if (rb_head->get_idx == rb_head->put_idx)
1812                 rb_head->state = SGHSC_RB_EMPTY;
1813         else
1814                 rb_head->state = SGHSC_RB_FLOAT;
1815 
1816         return (DDI_SUCCESS);
1817 }