| 53,9 → 53,79 |
|---|
| #define FAT_DENTRY_DOT 0x2e |
| #define FAT_DENTRY_ERASED 0xe5 |
| |
| static int match_path_component(fat_dentry_t *dentry, unsigned index, |
| size_t len) |
| /** 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) |
| { |
| 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; |
| |
| 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 */ |
| } |
| } |
| if (!dot_processed) { |
| dot_processed = true; |
| pos = -1; |
| if (PLB_GET_CHAR(cur) != '.') |
| return 0; |
| 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; |
| } |
| } |
| return 0; /* extra characters in the component */ |
| } |
| if (ext_processed || (name_processed && dentry->ext[0] == FAT_PAD)) |
| return cur - start; |
| else |
| return 0; |
| } |
| |
| void fat_lookup(ipc_callid_t rid, ipc_call_t *request) |