add directory study

study/linux-travel/MINIX-1.5/1.5/Source/amoeba/examples/server3.c

@@ -0,0 +1,104 @@
+#include <amoeba.h>
+#include <minix/callnr.h>
+#include <errno.h>
+#include "header.h"
+
+header hdr;				/* header for incoming messages */
+char buffer[BUF_SIZE+NAME_SIZE];	/* buffer for incoming messages */
+char *server_name = "filsrv";
+int repsize;
+extern int errno;
+
+main()
+{
+/* This is a primitive file server.  The client runs with a special set of
+ * routines for read(), write(), etc. that call this server.  The server is
+ * stateless.
+ */
+
+  int s;
+  int count;
+  unshort opcode, size;
+
+  strncpy( (char *) &hdr.h_port, server_name, PORTSIZE);  /* init port */
+
+  while (1) {
+	/* Wait for a request to arrive. */
+	count = (short) getreq(&hdr, buffer, MAX_TRANS);
+	if (count < 0) {
+	    printf("Server's getreq failed. Error = %d.   ", count);
+	    printf("Hit F1 to see if AMTASK running.\n");
+	    exit(1);
+	}
+	
+	/* Dispatch on opcode. */
+	opcode = hdr.h_command;
+	repsize = 0;
+	errno = 0;
+	switch(opcode) {
+		case CREAT:	s = do_creat();		break;
+		case READ:	s = do_read();		break;
+		case WRITE:	s = do_write();		break;
+		default:	s = EINVAL;		break;
+	}
+
+	/* Work done.  Send a reply. */
+	hdr.h_status = (unshort) s;
+ 	hdr.h_extra = (unshort) errno;
+	putrep(&hdr, buffer, repsize);
+  }
+}
+
+int do_read()
+{
+  /* Stateless read. */
+
+  int fd, n;
+  long offset;
+  unshort count;
+
+  offset = hdr.h_offset;
+  count = hdr.h_size;
+  if (count > MAX_TRANS) count = MAX_TRANS;
+
+  fd = open(buffer, 0);		/* open the file for reading */
+  if (fd < 0) return(errno);
+  lseek(fd, offset, 0);
+  n = read(fd, buffer, count);
+  close(fd);
+  repsize = n;
+  return(n);
+}
+
+int do_write()
+{
+  /* Stateless write. */
+
+  int fd, n;
+  long offset;
+  unshort count;
+
+  offset = hdr.h_offset;
+  count = hdr.h_size;
+  if (count > MAX_TRANS) count = MAX_TRANS;
+
+  fd = open(&buffer[BUF_SIZE], 2);		/* open the file for writing */
+  if (fd < 0) return(errno);
+  lseek(fd, offset, 0);
+  n = write(fd, buffer, count);
+  close(fd);
+  return(n);
+}
+
+int do_creat()
+{
+  /* Stateless creat. */
+
+  int fd, n, mode;
+  
+
+  mode = hdr.h_size;
+  fd = creat(buffer, mode);		/* creat the file  */ 
+  close(fd);
+  return(fd);
+}