fygue: support cluster chunk list generator for file (needed for the future read() primitive)

src/fs/fygue/fat/cluster.c

@@ -79,3 +79,16 @@ int fygue_fat_cluster_get_sector(
     }
     return 0;
 }
+
+/* fygue_fat_get_cluster_addr() - get logical sector addr */
+int fygue_fat_cluster_get_addr(
+    struct fygue_fat *fat,
+    uintptr_t *addr,
+    int cluster_id
+) {
+    int sector_id;
+
+    if (fygue_fat_cluster_get_sector(fat, cluster_id, &sector_id) != 0)
+        return -1;
+    return fygue_fat_sector_get_addr(fat, addr, sector_id);
+}

src/fs/fygue/fat/fat.h

@@ -83,6 +83,12 @@ struct fygue_fat_file
     int cluster_entry;
     int attribute;
     size_t size;
+    struct {
+        uintptr_t addr;
+        size_t size;
+        int cluster_count;
+    } *chunk;
+    int chunk_count;
 };
 
 /* fygue_fat_resolve: internal resolve information */
@@ -163,6 +169,13 @@ extern int fygue_fat_cluster_get_sector(
     int *sector_id
 );
 
+/* fygue_fat_get_cluster_addr() - get logical sector addr */
+extern int fygue_fat_cluster_get_addr(
+    struct fygue_fat *fat,
+    uintptr_t *addr,
+    int cluster_id
+);
+
 /* fygue_fat_get_sector_addr() - get logical sector addr */
 extern int fygue_fat_sector_get_addr(
     struct fygue_fat *fat,

src/fs/fygue/fat/initialize.c

@@ -149,25 +149,7 @@ static int _fygue_fat_configure(struct fygue_fat *fat)
 /* _fygue_fat_prepare() - prepare logic information */
 static int _fygue_fat_prepare(struct fygue_fat *fat)
 {
-    int rc;
-
-#if 0
-    rc = fygue_fat_sector_get_addr(
-        fat,
-        &fat->FAT0Addr,
-        fat->FAT0SectorID
-    );
-    if (rc != 0)
-        return -1;
-    rc = fygue_fat_sector_get_addr(
-        fat,
-        (void*)&fat->FAT1Addr,
-        fat->FAT1SectorID
-    );
-    if (rc != 0)
-        return -1;
-#endif
-    rc = fygue_flash_cmap_lsector_get_addr(
+    int rc = fygue_flash_cmap_lsector_get_addr(
         &fat->_flash.cmap,
         &fat->RootAddr,
         fat->RootSectorID

src/fs/fygue/fat/resolve.c

@@ -1,4 +1,5 @@
 #include <string.h>
+#include <stdlib.h>
 #include "fat.h"
 
 //---
@@ -30,8 +31,70 @@ static int _fygue_path_get_name(
     return 0;
 }
 
-/* _fugue_dirent_resolve(): convert found dirent to dir */
-static int _fygue_dirent_resolve(
+/* _fygue_dirent_resolve_file(): generate file information
+ *
+ * notes
+ *   - assume FAT integrity */
+static int _fygue_dirent_resolve_file(
+    struct fygue_fat *fat,
+    struct fygue_fat_file *file,
+    struct fygue_fat_dirent *dirent
+) {
+    uintptr_t cluster_addr_prev;
+    uintptr_t cluster_addr;
+    size_t cluster_size;
+    int cluster;
+    void *tmp;
+
+    memset(file, 0x00, sizeof(struct fygue_fat_file));
+    file->attribute     = dirent->attribute;
+    file->cluster_entry = dirent->cluster_id;
+    file->size          = dirent->size;
+    file->chunk         = NULL;
+    file->chunk_count   = 0;
+
+    cluster = file->cluster_entry;
+    cluster_size = fat->SectorSize * fat->SectorPerClus;
+    while (true)
+    {
+        if (fygue_fat_cluster_get_addr(fat, &cluster_addr, cluster) != 0)
+            goto error;
+        if (file->chunk_count > 0) {
+            cluster_addr_prev  = file->chunk[file->chunk_count - 1].addr;
+            cluster_addr_prev += file->chunk[file->chunk_count - 1].size;
+            if (cluster_addr == cluster_addr_prev) {
+                file->chunk[file->chunk_count - 1].size += cluster_size;
+                file->chunk[file->chunk_count - 1].cluster_count += 1;
+                if (fygue_fat_cluster_get_next(fat, &cluster) != 0)
+                    break;
+                continue;
+            }
+        }
+        tmp = reallocarray(
+            file->chunk,
+            file->chunk_count + 1,
+            sizeof(*file->chunk)
+        );
+        if (tmp == NULL)
+            goto error;
+        file->chunk = tmp;
+        file->chunk[file->chunk_count].size = cluster_size;
+        file->chunk[file->chunk_count].addr = cluster_addr;
+        file->chunk[file->chunk_count].cluster_count = 1;
+        file->chunk_count += 1;
+        if (fygue_fat_cluster_get_next(fat, &cluster) != 0)
+            break;
+    }
+    return 0;
+error:
+    if (file->chunk == NULL)
+        free(file->chunk);
+    memset(file, 0x00, sizeof(struct fygue_fat_file));
+    return -1;
+}
+
+/* _fugue_dirent_resolve_dir(): convert found dirent to dir */
+static int _fygue_dirent_resolve_dir(
     struct fygue_fat *fat,
     struct fygue_fat_dir *dir,
     struct fygue_fat_dirent *dirent
@@ -96,13 +159,10 @@ static int _fygue_resolve_set(
 ) {
     if (dirent == NULL || (dirent->attribute & FYGUE_FAT_ATTR_DIRECTORY)) {
         resolve->type = FYGUE_FAT_FILE_TYPE_DIR;
-        return _fygue_dirent_resolve(fat, &(resolve->dir), dirent);
+        return _fygue_dirent_resolve_dir(fat, &(resolve->dir), dirent);
     }
     resolve->type = FYGUE_FAT_FILE_TYPE_FILE;
-    resolve->file.attribute = dirent->attribute;
-    resolve->file.cluster_entry = dirent->cluster_id;
-    resolve->file.size = dirent->size;
-    return 0;
+    return _fygue_dirent_resolve_file(fat, &(resolve->file), dirent);
 }
 
 //---
@@ -134,7 +194,7 @@ int fygue_fat_resolve(
     while (true)
     {
         if (is_root) {
-            if (_fygue_dirent_resolve(fat, &dir, NULL) != 0)
+            if (_fygue_dirent_resolve_dir(fat, &dir, NULL) != 0)
                 return -3;
             if (_fygue_path_get_name(&prefix, &start, &len) != 0)
                 break;
@@ -145,7 +205,7 @@ int fygue_fat_resolve(
             return -4;
         if (_fygue_path_get_name(&prefix, &start, &len) != 0)
             break;
-        if (_fygue_dirent_resolve(fat, &dir, &dirent) != 0)
+        if (_fygue_dirent_resolve_dir(fat, &dir, &dirent) != 0)
             return -5;
     }
     if (is_root)