fygue: support readdir() + small fixes

CMakeLists.txt

@@ -263,6 +263,7 @@ set(SOURCES
   src/fs/fygue/fygue.c
   src/fs/fygue/fygue_open.c
   src/fs/fygue/fygue_syncfs.c
+  src/fs/fygue/fygue_dir_read.c
   src/fs/fygue/fat/cluster.c
   src/fs/fygue/fat/initialize.c
   src/fs/fygue/fat/readdir.c

src/fs/fygue/fat/fat.h

@@ -43,6 +43,7 @@ struct fygue_fat
 };
 
 /* fygue_fat_dirent - FAT dirent information */
+//TODO: flexible name array like the high-level `struct dirent` ?
 struct fygue_fat_dirent
 {
     char name[256];

src/fs/fygue/fat/resolve.c

@@ -102,10 +102,6 @@ static int _fygue_resolve_set(
 // Public
 //---
 
-char const *debug_prefix = "";
-char const *debug_start = "";
-size_t debug_len = 0;
-
 /* fygue_fat_resolve(): resolve any path provided
  *
  * notes
@@ -138,9 +134,6 @@ int fygue_fat_resolve(
             is_root = false;
             continue;
         }
-        debug_prefix = prefix;
-        debug_start = start;
-        debug_len = len;
         if (_fygue_dirent_find(fat, &dir, &dirent, start, len) != 0)
             return -4;
         if (_fygue_path_get_name(&prefix, &start, &len) != 0)

src/fs/fygue/fygue.c

@@ -55,9 +55,9 @@ int fygue_resolve(char const * const path, struct fygue_resolve *resolve)
         return -1;
     if (fygue_mount(&fsinfo, true) != 0)
         return -2;
-    int rc = fygue_fat_resolve(&(fsinfo->fat), path, &fat_resolve);
-    if (rc < 0)
-        return rc;
+    if (fygue_fat_resolve(&(fsinfo->fat), path, &fat_resolve) < 0)
+        return -3;
+    memset(resolve, 0x00, sizeof(struct fygue_resolve));
     if (fat_resolve.type == FYGUE_FAT_FILE_TYPE_FILE)
     {
         resolve->type = FYGUE_FILE_TYPE_DIR;
@@ -69,6 +69,7 @@ int fygue_resolve(char const * const path, struct fygue_resolve *resolve)
         );
     } else {
         resolve->type = FYGUE_FILE_TYPE_DIR;
+        resolve->dir.dirent = NULL;
         memcpy(
             &(resolve->dir.fat),
             &(fat_resolve.dir),
@@ -90,7 +91,7 @@ const fs_descriptor_type_t fygue_descriptor_type = {
 };
 
 const fs_descriptor_type_t fygue_dir_descriptor_type = {
-    .read   = NULL,
+    .read   = (void*)&fygue_dir_read,
     .write  = NULL,
     .lseek  = NULL,
     .close  = NULL,

src/fs/fygue/fygue.h

@@ -28,10 +28,7 @@ extern const fs_descriptor_type_t fygue_dir_descriptor_type;
 extern int fygue_open(char const *path, int flags, mode_t mode);
 
 /* fygue_stat() - get file or directory information */
-extern int fygue_stat(
-    char const * restrict path,
-    struct stat * restrict statbuf
-);
+extern int fygue_stat(char const *path, struct stat *statbuf);
 
 /* fygue_syncfs() - request filesystem re-synchronisation */
 extern int fygue_syncfs(void *desc);
@@ -44,11 +41,7 @@ extern int fygue_syncfs(void *desc);
 #include <errno.h>
 
 #define ENOTSUP_IF_NOT_FYGUE(rc)    \
-   if(                                  \
-        (gint[HWFS] != HWFS_FUGUE) ||   \
-        (flags & O_WRONLY) ||           \
-        (flags & O_RDWR)                \
-    ) {                                 \
+   if(gint[HWFS] != HWFS_FUGUE) {   \
        errno = ENOTSUP;             \
        return (rc);                 \
     }
@@ -75,6 +68,7 @@ struct fygue_resolve {
         } file;
         struct {
             struct fygue_fat_dir fat;
+            struct dirent *dirent;
         } dir;
     };
 };
@@ -98,6 +92,13 @@ extern int fygue_resolve(
     struct fygue_resolve *resolve
 );
 
+/* fygue_dir_read(): directory read implementation */
+extern int fygue_dir_read(
+    struct fygue_descriptor *desc,
+    struct dirent **dirent,
+    size_t size
+);
+
 #ifdef __cplusplus
 }
 #endif

src/fs/fygue/fygue_dir_read.c

@@ -0,0 +1,68 @@
+#include <stdlib.h>
+#include <string.h>
+#include "fygue.h"
+
+/* fygue_dir_read(): directory read implementation
+ *
+ * notes
+ *   - assume that the directory have read permission */
+int fygue_dir_read(
+    struct fygue_descriptor *desc,
+    struct dirent **dirent,
+    size_t size
+) {
+    struct fygue_fat_dirent fat_dirent;
+    struct fygue_fsinfo *fsinfo;
+    size_t len;
+    int rc;
+
+    ENOTSUP_IF_NOT_FYGUE(-1);
+
+    if (desc == NULL || desc->resolve.type != FYGUE_FILE_TYPE_DIR) {
+        errno = EBADF;
+        return -1;
+    }
+    if (dirent == NULL) {
+        errno = EFAULT;
+        return -1;
+    }
+    if (size < sizeof *dirent) {
+        errno = EINVAL;
+        return -1;
+    }
+    if (fygue_mount(&fsinfo, true) != 0) {
+        errno = EIO;
+        return -1;
+    }
+
+    /* get the next FAT dirent */
+    rc = fygue_fat_readdir(
+        &(fsinfo->fat),
+        &desc->resolve.dir.fat,
+        &fat_dirent
+    );
+    if (rc <= -3)
+        return 0;
+    if (rc < 0) {
+        errno = EIO;
+        return -1;
+    }
+
+    /* since `struct dirent` use flexible array to store the filename
+     * we need to reallocate the buffer each time */
+    //FIXME: ensure UTF-8/SHIFT-JS
+    len = strlen(fat_dirent.name);
+    *dirent = desc->resolve.dir.dirent;
+    *dirent = realloc(*dirent, sizeof(struct dirent) + len + 2);
+    if (*dirent == NULL) {
+        errno = ENOMEM;
+        return -1;
+    }
+
+    /* convert FAT dirent into generic dirent information */
+    //FIXME: ensure UTF-8/SHIFT-JS
+    (*dirent)->d_ino  = fat_dirent.cluster_id;
+    (*dirent)->d_type = DT_REG;
+    memcpy((*dirent)->d_name, fat_dirent.name, len + 1);
+    return 0;
+}

src/fs/fygue/fygue_open.c

@@ -12,6 +12,10 @@ int fygue_open(char const *path, int flags, GUNUSED mode_t mode)
     struct fygue_resolve resolve;
     fs_descriptor_t data;
 
+    if ((flags & O_RDWR) || (flags & O_WRONLY)) {
+        errno = EROFS;
+        return -1;
+    }
     ENOTSUP_IF_NOT_FYGUE(-1);
 
     /* resolve the entry */