| 1,5 → 1,5 |
|---|
| /* |
| * Copyright (c) 2007 Jakub Jermar |
| * Copyright (c) 2008 Jakub Jermar |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| 37,12 → 37,12 |
|---|
| |
| #include "fat.h" |
| #include "../../vfs/vfs.h" |
| #include <libfs.h> |
| #include <ipc/ipc.h> |
| #include <async.h> |
| #include <errno.h> |
| #include <string.h> |
| |
| #define PLB_GET_CHAR(i) (fat_reg.plb_ro[(i) % PLB_SIZE]) |
| |
| #define FAT_NAME_LEN 8 |
| #define FAT_EXT_LEN 3 |
| |
| 53,88 → 53,122 |
|---|
| #define FAT_DENTRY_DOT 0x2e |
| #define FAT_DENTRY_ERASED 0xe5 |
| |
| /** Compare one component of path to a directory entry. |
| * |
| * @param dentry Directory entry to compare the path component with. |
| * @param start Index into PLB where the path component starts. |
| * @param last Index of the last character of the path in PLB. |
| * |
| * @return Zero on failure or delta such that (index + delta) % |
| * PLB_SIZE points to a new path component in PLB. |
| */ |
| static unsigned match_path_component(fat_dentry_t *dentry, unsigned start, |
| unsigned last) |
| static void dentry_name_canonify(fat_dentry_t *d, char *buf) |
| { |
| unsigned cur; /* current position in PLB */ |
| int pos; /* current position in dentry->name or dentry->ext */ |
| bool name_processed = false; |
| bool dot_processed = false; |
| bool ext_processed = false; |
| int i; |
| |
| if (last < start) |
| last += PLB_SIZE; |
| for (pos = 0, cur = start; (cur <= last) && (PLB_GET_CHAR(cur) != '/'); |
| pos++, cur++) { |
| if (!name_processed) { |
| if ((pos == FAT_NAME_LEN - 1) || |
| (dentry->name[pos + 1] == FAT_PAD)) { |
| /* this is the last character in name */ |
| name_processed = true; |
| } |
| if (dentry->name[0] == FAT_PAD) { |
| /* name is empty */ |
| name_processed = true; |
| } else if ((pos == 0) && (dentry->name[pos] == |
| FAT_DENTRY_E5_ESC)) { |
| if (PLB_GET_CHAR(cur) == 0xe5) |
| continue; |
| else |
| return 0; /* character mismatch */ |
| } else { |
| if (PLB_GET_CHAR(cur) == dentry->name[pos]) |
| continue; |
| else |
| return 0; /* character mismatch */ |
| } |
| for (i = 0; i < FAT_NAME_LEN; i++) { |
| if (d->name[i] == FAT_PAD) { |
| buf++; |
| break; |
| } |
| if (!dot_processed) { |
| dot_processed = true; |
| pos = -1; |
| if (PLB_GET_CHAR(cur) != '.') |
| return 0; |
| if (d->name[i] == FAT_DENTRY_E5_ESC) |
| *buf++ = 0xe5; |
| else |
| *buf++ = d->name[i]; |
| } |
| if (d->ext[0] != FAT_PAD) |
| *buf++ = '.'; |
| for (i = 0; i < FAT_EXT_LEN; i++) { |
| if (d->ext[i] == FAT_PAD) { |
| *buf = '\0'; |
| return; |
| } |
| if (d->ext[i] == FAT_DENTRY_E5_ESC) |
| *buf++ = 0xe5; |
| else |
| *buf++ = d->ext[i]; |
| } |
| } |
| |
| static fat_dentry_t *fat_dentry_get(fat_node_t *dirnode, unsigned idx) |
| { |
| return NULL; /* TODO */ |
| } |
| |
| static void fat_dentry_put(fat_dentry_t *dentry) |
| { |
| /* TODO */ |
| } |
| |
| static void *fat_node_get(dev_handle_t dev_handle, fs_index_t index) |
| { |
| return NULL; /* TODO */ |
| } |
| |
| static void *fat_match(void *prnt, const char *component) |
| { |
| fat_node_t *parentp = (fat_node_t *)prnt; |
| char name[FAT_NAME_LEN + 1 + FAT_EXT_LEN + 1]; |
| unsigned i; |
| unsigned dentries; |
| fat_dentry_t *d; |
| |
| dentries = parentp->size / sizeof(fat_dentry_t); |
| for (i = 0; i < dentries; i++) { |
| d = fat_dentry_get(parentp, i); |
| if (d->attr & FAT_ATTR_VOLLABEL) { |
| /* volume label entry */ |
| fat_dentry_put(d); |
| continue; |
| } |
| if (!ext_processed) { |
| if ((pos == FAT_EXT_LEN - 1) || |
| (dentry->ext[pos + 1] == FAT_PAD)) { |
| /* this is the last character in ext */ |
| ext_processed = true; |
| } |
| if (dentry->ext[0] == FAT_PAD) { |
| /* ext is empty; the match will fail */ |
| ext_processed = true; |
| } else if (PLB_GET_CHAR(cur) == dentry->ext[pos]) { |
| continue; |
| } else { |
| /* character mismatch */ |
| return 0; |
| } |
| if (d->name[0] == FAT_DENTRY_ERASED) { |
| /* not-currently-used entry */ |
| fat_dentry_put(d); |
| continue; |
| } |
| return 0; /* extra characters in the component */ |
| if (d->name[0] == FAT_DENTRY_UNUSED) { |
| /* never used entry */ |
| fat_dentry_put(d); |
| break; |
| } |
| if (d->name[0] == FAT_DENTRY_DOT) { |
| /* |
| * Most likely '.' or '..'. |
| * It cannot occur in a regular file name. |
| */ |
| fat_dentry_put(d); |
| continue; |
| } |
| |
| dentry_name_canonify(d, name); |
| if (strcmp(name, component) == 0) { |
| /* hit */ |
| void *node = fat_node_get(parentp->dev_handle, |
| (fs_index_t)d->firstc); |
| fat_dentry_put(d); |
| return node; |
| |
| } else { |
| /* miss */ |
| fat_dentry_put(d); |
| } |
| } |
| if (ext_processed || (name_processed && dentry->ext[0] == FAT_PAD)) |
| return cur - start; |
| else |
| return 0; |
| |
| return NULL; |
| } |
| |
| /** libfs operations */ |
| libfs_ops_t fat_libfs_ops = { |
| .match = fat_match, |
| .node_get = fat_node_get, |
| .create = NULL, |
| .destroy = NULL, |
| .link = NULL, |
| .unlink = NULL, |
| .index_get = NULL, |
| .size_get = NULL, |
| .lnkcnt_get = NULL, |
| .has_children = NULL, |
| .root_get = NULL, |
| .plb_get_char = NULL, |
| .is_directory = NULL, |
| .is_file = NULL |
| }; |
| |
| void fat_lookup(ipc_callid_t rid, ipc_call_t *request) |
| { |
| int first = IPC_GET_ARG1(*request); |
| int second = IPC_GET_ARG2(*request); |
| int dev_handle = IPC_GET_ARG3(*request); |
| |
| |
| libfs_lookup(&fat_libfs_ops, fat_reg.fs_handle, rid, request); |
| } |
| |
| /** |