i/o redirection in sh

better parsing of sh commands (copied from jos sh)
cat: read from 1 if no args
sbrk system call, but untested
getpid system call
moved locks in keyboard intr, but why do we get intr w. null characters from keyboard?

1 files changed, 34 insertions, 23 deletions

diff --git a/ls.c b/ls.c
index 3441eba..34fac2a 100644
--- a/ls.c
+++ b/ls.c
@@ -7,13 +7,24 @@ char buf[512];
 struct stat st;
 struct dirent dirent;
 
+void
+pname(char *n)
+{
+  int i;
+
+  for (i = 0; (i < DIRSIZ) && (n[i] != '\0') ; i++) {
+      printf(1, "%c", n[i]);
+  }
+  for (; i < DIRSIZ; i++)
+    printf(1, " ");
+}
+
 int
 main(int argc, char *argv[])
 {
   int fd;
   uint off;
   uint sz;
-  int i;
 
   if(argc > 2){
     puts("Usage: ls [dir]\n");
@@ -23,7 +34,7 @@ main(int argc, char *argv[])
   if (argc == 2) {
     fd = open(argv[1], 0);
     if(fd < 0){
-      printf(2, "ls: cannot open dir %s\n", argv[1]);
+      printf(2, "ls: cannot open %s\n", argv[1]);
       exit();
     } 
   } else {
@@ -38,31 +49,31 @@ main(int argc, char *argv[])
     printf(2, "ls: cannot stat dir\n");
     exit();
   }
-  if (st.st_type != T_DIR) {
-    printf(2, "ls: dir is not a directory\n");
-  }
-  sz = st.st_size;
-  for(off = 0; off < sz; off += sizeof(struct dirent)) {
-    if (read(fd, &dirent, sizeof(struct dirent)) != sizeof(struct dirent)) {
-      printf(1, "ls: read error\n");
-      break;
-    }
-    if (dirent.inum != 0) {
-      // xxx prepend to name the pathname supplied to ls (e.g. .. in ls ..)
-      if (stat (dirent.name, &st) < 0)  {
-	printf(1, "stat: failed %s\n", dirent.name);
-	continue;
+
+  switch (st.st_type) {
+  case T_FILE:
+    pname(argv[1]);
+    printf(1, "%d %d %d\n", st.st_type, st.st_ino, st.st_size);
+    break;
+  case T_DIR:
+    sz = st.st_size;
+    for(off = 0; off < sz; off += sizeof(struct dirent)) {
+      if (read(fd, &dirent, sizeof(struct dirent)) != sizeof(struct dirent)) {
+	printf(1, "ls: read error\n");
+	break;
       }
-      for (i = 0; i < DIRSIZ; i++) {
-	if (dirent.name[i] != '\0')
-	  printf(1, "%c", dirent.name[i]);
-	else
-	  printf(1, " ");
+      if (dirent.inum != 0) {
+	// xxx prepend to name the pathname supplied to ls (e.g. .. in ls ..)
+	if (stat (dirent.name, &st) < 0)  {
+	  printf(1, "stat: failed %s\n", dirent.name);
+	  continue;
+	}
+	pname(dirent.name);
+	printf(1, "%d %d %d\n", st.st_type, dirent.inum, st.st_size);
       }
-      printf(1, "%d %d %d\n", st.st_type, dirent.inum, st.st_size);
     }
+    break;
   }
   close(fd);
-
   exit();
 }