1 files changed, 130 insertions, 0 deletions
diff --git a/src/ui_ipc.c b/src/ui_ipc.c
new file mode 100644
index 0000000..9eac79e
--- /dev/null
+++ b/src/ui_ipc.c
@@ -0,0 +1,130 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <strings.h>
+#ifdef SEM_TIMEDWAIT
+#include <time.h>
+#endif
+#include <semaphore.h>
+#include <mqueue.h>
+#include <sys/stat.h>
+#include <errno.h>
+
+#include "ui_ipc.h"
+
+#define JMP_IF(cmd, retval, jmplabel) if ( (cmd) == retval ) {  printf("(%s) == %p\n", #cmd, (void*)retval);  goto jmplabel; }
+
+
+static sem_t *sems[SEM_NUM];
+static mqd_t msqs[MSQ_NUM];
+
+
+int
+ui_ipc_init(int is_master)
+{
+  volatile int sp_oflags, mq_oflags;
+  mode_t crt_flags;
+  struct mq_attr m_attr;
+
+  bzero(sems, sizeof(sem_t*)*SEM_NUM);
+  bzero(msqs, sizeof(mqd_t)*MSQ_NUM);
+  m_attr.mq_flags = 0;
+  m_attr.mq_msgsize = IPC_MQSIZ;
+  m_attr.mq_maxmsg = 3;
+  m_attr.mq_curmsgs = 0;
+  if (is_master) {
+    sp_oflags = O_CREAT | O_EXCL;
+    mq_oflags = O_NONBLOCK | O_CREAT | O_EXCL;
+    crt_flags = S_IRUSR | S_IWUSR;
+    JMP_IF( msqs[MQ_PW]  = mq_open(MSQ_PWD, mq_oflags | O_RDONLY, crt_flags, &m_attr), (mqd_t)-1, error );
+    JMP_IF( msqs[MQ_IF]  = mq_open(MSQ_INF, mq_oflags | O_WRONLY, crt_flags, &m_attr), (mqd_t)-1, error );
+  } else {
+    sp_oflags = 0;
+    mq_oflags = 0;
+    crt_flags = 0;
+    JMP_IF( msqs[MQ_PW]  = mq_open(MSQ_PWD, mq_oflags | O_WRONLY, crt_flags, &m_attr), (mqd_t)-1, error );
+    JMP_IF( msqs[MQ_IF]  = mq_open(MSQ_INF, mq_oflags | O_RDONLY, crt_flags, &m_attr), (mqd_t)-1, error );
+  }
+  JMP_IF( sems[SEM_UI] = sem_open(SEM_GUI, sp_oflags, crt_flags, 0), SEM_FAILED, error );
+  JMP_IF( sems[SEM_IN] = sem_open(SEM_INP, sp_oflags, crt_flags, 0), SEM_FAILED, error );
+  JMP_IF( sems[SEM_BS] = sem_open(SEM_BSY, sp_oflags, crt_flags, 0), SEM_FAILED, error );
+  JMP_IF( sems[SEM_RD] = sem_open(SEM_RDY, sp_oflags, crt_flags, 0), SEM_FAILED, error );
+  return 0;
+error:
+  return errno;
+}
+
+void
+ui_ipc_free(int is_master)
+{
+  int i;
+
+  for (i = 0; i < SEM_NUM; i++) {
+    if (sems[i]) sem_close(sems[i]);
+  }
+  for (i = 0; i < MSQ_NUM; i++) {
+    if (msqs[i]) mq_close(msqs[i]);
+  }
+  if (is_master > 0) {
+    sem_unlink(SEM_BSY);
+    sem_unlink(SEM_GUI);
+    sem_unlink(SEM_INP);
+    sem_unlink(SEM_RDY);
+    mq_unlink(MSQ_PWD);
+    mq_unlink(MSQ_INF);
+  }
+}
+
+int
+ui_ipc_sempost(enum UI_IPC_SEM e_sp)
+{
+  return ( sem_post(sems[e_sp]) );
+}
+
+int
+ui_ipc_semwait(enum UI_IPC_SEM e_sp)
+{
+  return ( sem_wait(sems[e_sp]) );
+}
+
+int
+ui_ipc_semtrywait(enum UI_IPC_SEM e_sp)
+{
+  return ( sem_trywait(sems[e_sp]) );
+}
+
+int
+ui_ipc_getvalue(enum UI_IPC_SEM e_sp)
+{
+  int sp_val = 0;
+
+  if (sem_getvalue(sems[e_sp], &sp_val) != 0) {
+    return -1;
+  }
+  return sp_val;
+}
+
+#ifdef SEM_TIMEDWAIT
+int
+ui_ipc_semtimedwait(enum UI_IPC_SEM e_sp, int timeout)
+{
+  struct timespec ts;
+  if (clock_gettime(CLOCK_REALTIME, &ts) == -1) {
+    return -1;
+  }
+  ts.tc_sec += timeout;
+  return ( sem_timedwait(sems[q_mq], &ts) );
+}
+#endif
+
+int
+ui_ipc_msgsend(enum UI_IPC_MSQ e_mq, const char *msg_ptr, size_t msg_len)
+{
+  return ( mq_send(msqs[e_mq], msg_ptr, msg_len, 0) );
+}
+
+ssize_t
+ui_ipc_msgrecv(enum UI_IPC_MSQ e_mq, char *msg_ptr, size_t msg_len)
+{
+  return ( mq_receive(msqs[e_mq], msg_ptr, msg_len, NULL) ); 
+}
+