X-Git-Url: https://wimlib.net/git/?a=blobdiff_plain;f=src%2Fsymlink.c;h=ca2e422fca2176e49f6f6b1054bc0667736bcce0;hb=81be60d782a4b4b8ae2e40141fc42b6e0e2d2706;hp=c94ba7509c01ae6c01dbe3abf78862613fdfa6ab;hpb=0bf41495dd9e04585be10794d7745a5baa7165a5;p=wimlib diff --git a/src/symlink.c b/src/symlink.c index c94ba750..ca2e422f 100644 --- a/src/symlink.c +++ b/src/symlink.c @@ -1,3 +1,28 @@ +/* + * symlink.c + * + * Code to read and set symbolic links in WIM files. + */ + +/* + * Copyright (C) 2012 Eric Biggers + * + * This file is part of wimlib, a library for working with WIM files. + * + * wimlib is free software; you can redistribute it and/or modify it under the + * terms of the GNU Lesser General Public License as published by the Free + * Software Foundation; either version 2.1 of the License, or (at your option) + * any later version. + * + * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY + * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR + * A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more + * details. + * + * You should have received a copy of the GNU Lesser General Public License + * along with wimlib; if not, see http://www.gnu.org/licenses/. + */ + #include "dentry.h" #include "io.h" #include "lookup_table.h" @@ -80,7 +105,12 @@ static ssize_t get_symlink_name(const u8 *resource, size_t resource_len, translated_target += 4; link_target_len -= 4; /* There's a drive letter, so just leave the backslashes since - * it won't go anyhwere on UNIX anyway... */ + * it won't go anyhwere on UNIX anyway... + * + * XXX + * NTFS-3g tries to re-map these links to actually point to + * something, so maybe we could do something like that here + * XXX*/ } else { for (size_t i = 0; i < link_target_len; i++) if (translated_target[i] == '\\') @@ -112,9 +142,9 @@ void *make_symlink_reparse_data_buf(const char *symlink_target, size_t *len_ret) /* XXX Fix absolute paths */ u8 *p = buf; - p = put_u16(p, 0); /* Substitute name offset */ + p = put_u16(p, utf16_len); /* Substitute name offset */ p = put_u16(p, utf16_len); /* Substitute name length */ - p = put_u16(p, utf16_len); /* Print name offset */ + p = put_u16(p, 0); /* Print name offset */ p = put_u16(p, utf16_len); /* Print name length */ p = put_u32(p, 1); p = put_bytes(p, utf16_len, name_utf16); @@ -126,63 +156,64 @@ out: return buf; } -/* Get the symlink target from a dentry that's already checked to be either a - * "real" symlink or a junction point. */ +/* Get the symlink target from a dentry. + * + * The dentry may be either "real" symlink or a junction point. + */ ssize_t dentry_readlink(const struct dentry *dentry, char *buf, size_t buf_len, const WIMStruct *w) { - struct resource_entry *res_entry; - struct lookup_table_entry *lte; - u16 i = 0; - const u8 *hash = dentry->hash; + const struct lookup_table_entry *lte; + int ret; wimlib_assert(dentry_is_symlink(dentry)); - while (1) { - if ((lte = __lookup_resource(w->lookup_table, hash))) - break; - if (i == dentry->num_ads) - return -EIO; - hash = dentry->ads_entries[i].hash; - i++; - } - res_entry = <e->resource_entry; - if (res_entry->original_size > 10000) + lte = dentry_first_lte(dentry, w->lookup_table); + if (!lte) return -EIO; - char __res_buf[res_entry->original_size]; - const char *res_buf; - if (lte->is_symlink && lte->symlink_buf) { - res_buf = lte->symlink_buf; - } else { - res_buf = __res_buf; - if (read_full_resource(w->fp, res_entry->size, - res_entry->original_size, - res_entry->offset, - wim_resource_compression_type(w, res_entry), - __res_buf) != 0) - return -EIO; - res_buf = __res_buf; - } - return get_symlink_name(res_buf, res_entry->original_size, buf, + if (wim_resource_size(lte) > 10000) + return -EIO; + + char res_buf[wim_resource_size(lte)]; + ret = read_full_wim_resource(lte, res_buf); + if (ret != 0) + return -EIO; + return get_symlink_name(res_buf, wim_resource_size(lte), buf, buf_len, dentry->reparse_tag); } static int dentry_set_symlink_buf(struct dentry *dentry, - const u8 symlink_buf_hash[]) + struct lookup_table_entry *lte) { struct ads_entry *ads_entries; ads_entries = CALLOC(2, sizeof(struct ads_entry)); if (!ads_entries) return WIMLIB_ERR_NOMEM; - memcpy(ads_entries[1].hash, symlink_buf_hash, WIM_HASH_SIZE); - dentry_free_ads_entries(dentry); + + wimlib_assert(dentry->num_ads == 0); + wimlib_assert(dentry->ads_entries == NULL); + + ads_entries[0].lte = lte; + + /*dentry_free_ads_entries(dentry);*/ dentry->num_ads = 2; dentry->ads_entries = ads_entries; return 0; } +/* + * Sets @dentry to be a symbolic link pointing to @target. + * + * A lookup table entry for the symbolic link data buffer is created and + * inserted into @lookup_table, unless there is an existing lookup table entry + * for the exact same data, in which its reference count is incremented. + * + * The lookup table entry is returned in @lte_ret. + * + * On failure @dentry and @lookup_table are not modified. + */ int dentry_set_symlink(struct dentry *dentry, const char *target, struct lookup_table *lookup_table, struct lookup_table_entry **lte_ret) @@ -191,7 +222,7 @@ int dentry_set_symlink(struct dentry *dentry, const char *target, int ret; size_t symlink_buf_len; struct lookup_table_entry *lte = NULL, *existing_lte; - u8 symlink_buf_hash[WIM_HASH_SIZE]; + u8 symlink_buf_hash[SHA1_HASH_SIZE]; void *symlink_buf; symlink_buf = make_symlink_reparse_data_buf(target, &symlink_buf_len); @@ -199,14 +230,16 @@ int dentry_set_symlink(struct dentry *dentry, const char *target, return WIMLIB_ERR_NOMEM; DEBUG("Made symlink reparse data buf (len = %zu, name len = %zu)", - symlink_buf_len, ret); + symlink_buf_len, symlink_buf_len); sha1_buffer(symlink_buf, symlink_buf_len, symlink_buf_hash); existing_lte = __lookup_resource(lookup_table, symlink_buf_hash); if (existing_lte) { - existing_lte->refcnt++; + lte = existing_lte; + FREE(symlink_buf); + symlink_buf = NULL; } else { DEBUG("Creating new lookup table entry for symlink buf"); lte = new_lookup_table_entry(); @@ -214,27 +247,33 @@ int dentry_set_symlink(struct dentry *dentry, const char *target, ret = WIMLIB_ERR_NOMEM; goto out_free_symlink_buf; } - lte->is_symlink = true; - lte->symlink_buf = symlink_buf; + lte->resource_location = RESOURCE_IN_ATTACHED_BUFFER; + lte->attached_buffer = symlink_buf; lte->resource_entry.original_size = symlink_buf_len; - lte->resource_entry.size = symlink_buf_len; - memcpy(lte->hash, symlink_buf_hash, WIM_HASH_SIZE); + lte->resource_entry.size = symlink_buf_len; + lte->resource_entry.flags = 0; + copy_hash(lte->hash, symlink_buf_hash); } - ret = dentry_set_symlink_buf(dentry, symlink_buf_hash); + ret = dentry_set_symlink_buf(dentry, lte); if (ret != 0) goto out_free_lte; + dentry->resolved = true; + DEBUG("Loaded symlink buf"); - if (!existing_lte) + if (existing_lte) + lte->refcnt++; + else lookup_table_insert(lookup_table, lte); if (lte_ret) *lte_ret = lte; return 0; out_free_lte: - FREE(lte); + if (lte != existing_lte) + FREE(lte); out_free_symlink_buf: FREE(symlink_buf); return ret;