From: Matthias Kruk <m@m10k.eu>
Date: Tue, 28 Jul 2020 13:22:15 +0000 (+0900)
Subject: libc: Add pipe() function for use in userspace processes
X-Git-Url: https://git.corax.cc/?a=commitdiff_plain;h=18a1b2d0ecf082b2cb30147aa03d74f9275755d2;p=corax

libc: Add pipe() function for use in userspace processes
---

diff --git a/include/unistd.h b/include/unistd.h
index 5011b68..09e2937 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -13,4 +13,6 @@ extern unsigned int sleep(unsigned int);
 extern int brk(void*);
 extern void* sbrk(int);
 
+extern int pipe(int pipefd[2]);
+
 #endif /* _UNISTD_H */
diff --git a/libc/unistd.c b/libc/unistd.c
new file mode 100644
index 0000000..f0947d0
--- /dev/null
+++ b/libc/unistd.c
@@ -0,0 +1,48 @@
+#include <unistd.h>
+#include <corax/ipc.h>
+#include <corax/ipc/io.h>
+#include <crxstd.h>
+#include <string.h>
+#include <errno.h>
+
+int pipe(int pipefd[2])
+{
+	struct cxmsg msg;
+	struct cxio_pipe *data;
+	int ret_val;
+
+	data = (struct cxio_pipe*)msg.cm_data;
+	data->flags = 0;
+
+	msg.cm_len = sizeof(*data);
+	msg.cm_type = CXIO_PIPE;
+
+	ret_val = cxsendrecv(PID_IO, &msg);
+
+	if(!ret_val) {
+		struct cxio_response *resp;
+
+		resp = (struct cxio_response*)msg.cm_data;
+
+		ret_val = resp->retval;
+		errno = resp->error;
+
+		if(!ret_val) {
+			/*
+			 * Call has succeeded, but we should still check if the amount
+			 * of data returned by the IO process has the expected size.
+			 */
+			if(resp->extralen == sizeof(int[2])) {
+				memcpy(pipefd, resp->extradata, resp->extralen);
+			} else {
+				ret_val = -1;
+				errno = EFAULT;
+			}
+		}
+	} else {
+		ret_val = -1;
+		errno = EFAULT;
+	}
+
+	return(ret_val);
+}