Fetching directory entries

kernel/fs/portlfs/portlfs.c

@@ -160,6 +160,52 @@ struct VfsObj *littlefs_open(struct VfsMountPoint *vmp, const char *path, uint32
   return vobj;
 }
 
+int32_t littlefs_fetchdirent(struct VfsMountPoint *vmp, const char *path, IoctlDirent *direntbuf, size_t idx) {
+  size_t i = 0;
+  struct lfs_info statinfo;
+  int ok;
+
+  spinlock_acquire(&vmp->spinlock);
+  
+  ok = lfs_stat(&vmp->fs.littlefs.instance, path, &statinfo);
+  if (ok < 0) {
+    spinlock_release(&vmp->spinlock);
+    return E_BADIO;
+  }
+
+  if (statinfo.type != LFS_TYPE_DIR) {
+    spinlock_release(&vmp->spinlock);
+    return E_BADIO;
+  }
+
+  lfs_dir_t dir;
+  ok = lfs_dir_open(&vmp->fs.littlefs.instance, &dir, path);
+  if (ok < 0) { 
+    spinlock_release(&vmp->spinlock);
+    return E_BADIO;
+  }
+
+  struct lfs_info entinfo;
+  while (lfs_dir_read(&vmp->fs.littlefs.instance, &dir, &entinfo) > 0) {
+    if (i == idx) {
+      if (entinfo.type == LFS_TYPE_REG) {
+        direntbuf->stat.type = IOCTLSTAT_FILE;
+        direntbuf->stat.size = entinfo.size;
+      } else if (entinfo.type == LFS_TYPE_DIR) {
+        direntbuf->stat.type = IOCTLSTAT_DIR;
+      }
+
+      hal_memcpy(direntbuf->name, entinfo.name, sizeof(direntbuf->name));
+      break;
+    }
+    i++;
+  }
+  
+  lfs_dir_close(&vmp->fs.littlefs.instance, &dir);
+
+  spinlock_release(&vmp->spinlock);
+}
+
 int portlfs_read(const struct lfs_config *c, lfs_block_t block, lfs_off_t off, void *buffer, lfs_size_t size) {
   VfsMountPoint *vmp = c->context;
   vmp->backingsd->read(vmp->backingsd, buffer, size, block * LITTLEFS_BLOCK_SIZE + off);

kernel/fs/portlfs/portlfs.h

@@ -4,6 +4,7 @@
 #include <stdint.h>
 #include <stdbool.h>
 #include "fs/littlefs/lfs.h"
+#include "sysdefs/ioctl.h"
 
 #define LITTLEFS_BLOCK_SIZE 4096
 
@@ -18,6 +19,7 @@ typedef struct {
 int32_t littlefs_cleanup(struct VfsMountPoint *vmp);
 struct VfsObj *littlefs_open(struct VfsMountPoint *vmp, const char *path, uint32_t flags);
 int32_t littlefs_stat(struct VfsMountPoint *vmp, const char *path, struct VfsStat *statbuf);
+int32_t littlefs_fetchdirent(struct VfsMountPoint *vmp, const char *path, IoctlDirent *direntbuf, size_t idx);
 
 int portlfs_read(const struct lfs_config *c, lfs_block_t block, lfs_off_t off, void *buffer, lfs_size_t size);
 int portlfs_prog(const struct lfs_config *c, lfs_block_t block, lfs_off_t off, const void *buffer, lfs_size_t size);

kernel/syscall/ioctl.c

@@ -161,6 +161,29 @@ int32_t SYSCALL5(sys_ioctl, ioh1, cmd1, arg1, arg2, arg3) {
       iostat->size = stat1.size;
       iostat->type = stat1.type;
     } break;
+    case IOCTL_FETCHDIRENT: {
+      const char *opath = (const char *)arg1;
+      
+      if (opath == NULL) {
+        ret = E_INVALIDARGUMENT;
+        goto done;
+      }
+
+      IoctlDirent *direntbuf = (IoctlDirent *)arg2;
+      if (direntbuf == NULL) {
+        ret = E_INVALIDARGUMENT;
+        goto done;
+      }
+
+      size_t idx = (size_t)arg3;
+      
+      char mp[IOCTL_MP_MAX];
+      char path[IOCTL_PATH_MAX];
+
+      path_parse(opath, mp, path);
+
+      ret = vfs_fetchdirent(mp, path, direntbuf, idx);
+    } break;
     default: {
       ret = E_INVALIDARGUMENT;
       goto done;

kernel/vfs/vfs.c

@@ -47,6 +47,7 @@ void vfs_init_littlefs(VfsMountPoint *mp, bool format) {
   mp->cleanup = &littlefs_cleanup;
   mp->open = &littlefs_open;
   mp->stat = &littlefs_stat;
+  mp->fetchdirent = &littlefs_fetchdirent;
 }
 
 int32_t vfs_stat(char *mountpoint, const char *path, VfsStat *stat) {
@@ -63,6 +64,20 @@ int32_t vfs_stat(char *mountpoint, const char *path, VfsStat *stat) {
   return mp->stat(mp, path, stat);
 }
 
+int32_t vfs_fetchdirent(char *mountpoint, const char *path, IoctlDirent *direntbuf, size_t idx) {
+  VfsMountPoint *mp = NULL;
+
+  spinlock_acquire(&VFS_TABLE.spinlock);
+  HSHTB_GET(&VFS_TABLE, mountpoints, mountpoint, label, mp);
+  spinlock_release(&VFS_TABLE.spinlock);
+
+  if (mp == NULL) {
+    return E_NOENTRY;
+  }
+
+  return mp->fetchdirent(mp, path, direntbuf, idx);
+}
+
 int32_t vfs_mount(char *mountpoint, int32_t fstype, StoreDev *backingsd, bool format) {
   VfsMountPoint *mp = NULL;
 

kernel/vfs/vfs.h

@@ -7,6 +7,7 @@
 #include "spinlock/spinlock.h"
 #include "fs/portlfs/portlfs.h"
 #include "storedev/storedev.h"
+#include "sysdefs/ioctl.h"
 
 #define VFS_MOUNTPOINT_LABEL_MAX 128
 #define VFS_MOUNTPOINTS_MAX 30
@@ -58,6 +59,7 @@ typedef struct VfsMountPoint {
   VfsObj *(*open)(struct VfsMountPoint *vmp, const char *path, uint32_t flags);
   int32_t (*cleanup)(struct VfsMountPoint *vmp);
   int32_t (*stat)(struct VfsMountPoint *vmp, const char *path, struct VfsStat *statbuf);
+  int32_t (*fetchdirent)(struct VfsMountPoint *vmp, const char *path, IoctlDirent *direntbuf, size_t idx);
 
   union {
     LittleFs littlefs;
@@ -78,5 +80,6 @@ int32_t vfs_mount(char *mountpoint, int32_t fstype, StoreDev *backingsd, bool fo
 void vfs_close(VfsObj *vobj);
 VfsObj *vfs_open(char *mountpoint, const char *path, uint32_t flags);
 int32_t vfs_stat(char *mountpoint, const char *path, VfsStat *stat);
+int32_t vfs_fetchdirent(char *mountpoint, const char *path, IoctlDirent *direntbuf, size_t idx);
 
 #endif // VFS_VFS_H_