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-rw-r--r--src/lib9/_p9proc.c73
1 files changed, 73 insertions, 0 deletions
diff --git a/src/lib9/_p9proc.c b/src/lib9/_p9proc.c
new file mode 100644
index 00000000..6e4010cd
--- /dev/null
+++ b/src/lib9/_p9proc.c
@@ -0,0 +1,73 @@
+#include <u.h>
+#include <libc.h>
+#include "9proc.h"
+
+static Lock uproclock;
+static Uproc *phash[PIDHASH];
+
+Uproc*
+_p9uproc(void)
+{
+ /* for now, assume getpid is fast or cached */
+ int pid;
+ Uproc *up;
+
+ pid = getpid();
+again:
+if(0)print("find %d\n", pid);
+ lock(&uproclock);
+ for(up=phash[pid%PIDHASH]; up; up=up->next){
+ if(up->pid == pid){
+if(0)print("found %d\n", pid);
+ unlock(&uproclock);
+ return up;
+ }
+ }
+
+ up = mallocz(sizeof(Uproc), 1);
+ if(up == nil){
+if(0)print("again %d\n", pid);
+ unlock(&uproclock);
+ sleep(1000);
+ goto again;
+ }
+
+againpipe:
+ if(pipe(up->pipe) < 0){
+if(0)print("againpipe %d\n", pid);
+ sleep(1000);
+ goto againpipe;
+ }
+
+ up->pid = pid;
+ up->next = phash[pid%PIDHASH];
+ phash[pid%PIDHASH] = up;
+if(0)print("link %d\n", pid);
+ unlock(&uproclock);
+ return up;
+}
+
+void
+_p9uprocdie(void)
+{
+ Uproc **l, *up;
+ int pid;
+
+ pid = getpid();
+if(0)print("die %d\n", pid);
+ lock(&uproclock);
+ for(l=&phash[pid%33]; *l; l=&(*l)->next){
+ if((*l)->pid == pid){
+ up = *l;
+ *l = up->next;
+if(0)print("died %d\n", pid);
+ unlock(&uproclock);
+ close(up->pipe[0]);
+ close(up->pipe[1]);
+ free(up);
+ return;
+ }
+ }
+if(0)print("not started %d\n", pid);
+ unlock(&uproclock);
+}