Changeset 5973fd0 in mainline

Timestamp:

2008-01-18T23:45:16Z (16 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

ae78b53

Parents:

62da45a

Message:

Finish implementation of readdir(). Functions from this family are implemented
via using file descriptors for directories. For example, readdir() is
implemented as read() from an open directory. Of course, FS implementations
must understand that they are asked to read a directory and behave accordingly.

Location:

uspace

Files:

• app/tester/vfs/vfs1.c (modified) (4 diffs)
• lib/libc/generic/vfs.c (modified) (2 diffs)
• lib/libc/include/dirent.h (modified) (1 diff)
• srv/fs/tmpfs/tmpfs_ops.c (modified) (2 diffs)

uspace/app/tester/vfs/vfs1.c

@@ -1 +1 @@
 /*
- * Copyright (c) 2007 Jakub Jermar
+ * Copyright (c) 2008 Jakub Jermar
  * All rights reserved.
  *
@@ -35 +35 @@
 #include <unistd.h>
 #include <fcntl.h>
+#include <dirent.h>
 #include "../tester.h"
 
@@ -41 +42 @@
         if (mount("tmpfs", "/", "nulldev0") != EOK)
                 return "Mount failed.\n";
+
+
+        DIR *dirp;
+        struct dirent *dp;
+
+        dirp = opendir("/");
+        if (!dirp)
+                return "opendir() failed.";
+        while ((dp = readdir(dirp)))
+                printf("Discovered %s\n", dp->d_name);
+        closedir(dirp);
+
         int fd1 = open("/dir1/file1", 0);
         int fd2 = open("/dir2/file2", 0);
 
         if (fd1 < 0)
-                return "Open failed.\n";
+                return "open() failed.\n";
         if (fd2 < 0)
-                return "Open failed.\n";
+                return "open() failed.\n";
 
         if (!quiet)
@@ -56 +69 @@
         ssize_t cnt = read(fd1, buf, sizeof(buf));
         if (cnt < 0)
-                return "Read failed.\n";
+                return "read() failed.\n";
 
         if (!quiet)

uspace/lib/libc/generic/vfs.c

@@ -244 +244 @@
                 return NULL;
         dirp->fd = open(dirname, 0);    /* TODO: must be a directory */
-        if (!dirp->fd) {
+        if (dirp->fd < 0) {
                 free(dirp);
                 return NULL;
         }
-        dirp->pos = 0;
         return dirp;
 }
@@ -254 +253 @@
 struct dirent *readdir(DIR *dirp)
 {
-        return NULL;    /* TODO */      
+        ssize_t len = read(dirp->fd, &dirp->res.d_name[0], NAME_MAX + 1);
+        if (len <= 0)
+                return NULL;
+        return &dirp->res;
 }
 
 void rewinddir(DIR *dirp)
 {
-        dirp->pos = 0;
+        (void) lseek(dirp->fd, 0, SEEK_SET);
 }
 

uspace/lib/libc/include/dirent.h

@@ -44 +44 @@
 typedef struct {
         int fd;
-        unsigned pos;
         struct dirent res;
 } DIR;

uspace/srv/fs/tmpfs/tmpfs_ops.c

@@ -46 +46 @@
 #include <string.h>
 #include <stdio.h>
+#include <assert.h>
 #include <sys/types.h>
 #include <libadt/hash_table.h>
@@ -308 +309 @@
         }
 
-        size_t bytes = max(0, min(dentry->size - pos, len));
-        (void) ipc_data_read_finalize(callid, dentry->data + pos, bytes);
+        size_t bytes;
+        if (dentry->type == TMPFS_FILE) {
+                bytes = max(0, min(dentry->size - pos, len));
+                (void) ipc_data_read_finalize(callid, dentry->data + pos,
+                    bytes);
+        } else {
+                int i;
+                tmpfs_dentry_t *cur = dentry->child;
+                
+                assert(dentry->type == TMPFS_DIRECTORY);
+                
+                /*
+                 * Yes, we really use O(n) algorithm here.
+                 * If it bothers someone, it could be fixed by introducing a
+                 * hash table.
+                 */
+                for (i = 0, cur = dentry->child; i < pos && cur; i++,
+                    cur = cur->sibling)
+                        ;
+
+                if (!cur) {
+                        ipc_answer_0(callid, ENOENT);
+                        ipc_answer_1(rid, ENOENT, 0);
+                        return;
+                }
+
+                (void) ipc_data_read_finalize(callid, cur->name,
+                    strlen(cur->name) + 1);
+                bytes = 1;
+        }
 
         /*