X-Git-Url: https://wimlib.net/git/?p=wimlib;a=blobdiff_plain;f=src%2Fsymlink.c;h=bed8fc3e06c7774934e54c1c05a42faebd6ed74e;hp=f7fa10d4a89b2ce4e55024749be8ec8b10c6f368;hb=d0e7f039e4ab206b9fd973c983e3fb841fcd2bf2;hpb=8a7aa1e0e77c5fadb2ee4d062b90532f709f7883 diff --git a/src/symlink.c b/src/symlink.c index f7fa10d4..bed8fc3e 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 General Public License as published by the Free + * Software Foundation; either version 3 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 General Public License for more + * details. + * + * You should have received a copy of the GNU General Public License + * along with wimlib; if not, see http://www.gnu.org/licenses/. + */ + #include "dentry.h" #include "io.h" #include "lookup_table.h" @@ -55,7 +80,7 @@ static ssize_t get_symlink_name(const u8 *resource, size_t resource_len, } if (header_size + substitute_name_offset + substitute_name_len > resource_len) return -EIO; - link_target = utf16_to_utf8(p + substitute_name_offset, + link_target = utf16_to_utf8((const char *)p + substitute_name_offset, substitute_name_len, &link_target_len); @@ -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] == '\\') @@ -103,22 +133,24 @@ void *make_symlink_reparse_data_buf(const char *symlink_target, size_t *len_ret) return NULL; /*DEBUG("utf16_len = %zu", utf16_len);*/ for (size_t i = 0; i < utf16_len / 2; i++) - if (((u16*)name_utf16)[i] == to_le16('/')) - ((u16*)name_utf16)[i] = to_le16('\\'); - size_t len = 12 + utf16_len * 2; + if (((u16*)name_utf16)[i] == cpu_to_le16('/')) + ((u16*)name_utf16)[i] = cpu_to_le16('\\'); + size_t len = 12 + utf16_len * 2 + 4; void *buf = MALLOC(len); if (!buf) goto out; /* XXX Fix absolute paths */ u8 *p = buf; - p = put_u16(p, 0); /* Substitute name offset */ + p = put_u16(p, utf16_len + 2); /* 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); - p = put_bytes(p, utf16_len, name_utf16); + p = put_bytes(p, utf16_len, (const u8*)name_utf16); + p = put_u16(p, 0); + p = put_bytes(p, utf16_len, (const u8*)name_utf16); + p = put_u16(p, 0); /*DEBUG("utf16_len = %zu, len = %zu", utf16_len, len);*/ *len_ret = len; out: @@ -126,106 +158,70 @@ out: return buf; } -static const struct lookup_table_entry * -dentry_first_lte(const struct dentry *dentry, const struct lookup_table *table) -{ - const struct lookup_table_entry *lte; - if (dentry->resolved) { - if (dentry->lte) - return dentry->lte; - for (u16 i = 0; i < dentry->num_ads; i++) - if (dentry->ads_entries[i].lte) - return dentry->ads_entries[i].lte; - } else { - const u8 *hash = dentry->hash; - u16 i = 0; - while (1) { - if ((lte = __lookup_resource(table, hash))) - break; - if (i == dentry->num_ads) - return NULL; - hash = dentry->ads_entries[i].hash; - i++; - } - } - return NULL; -} - -/* Get the symlink target from a dentry that's already checked to be either a - * "real" symlink or a junction point. */ -ssize_t dentry_readlink(const struct dentry *dentry, char *buf, size_t buf_len, - const WIMStruct *w) +/* Get the symlink target from a dentry. + * + * The dentry may be either "real" symlink or a junction point. + */ +ssize_t inode_readlink(const struct inode *inode, char *buf, size_t buf_len, + const WIMStruct *w) { - const struct resource_entry *res_entry; const struct lookup_table_entry *lte; + int ret; - wimlib_assert(dentry_is_symlink(dentry)); + wimlib_assert(inode_is_symlink(inode)); - lte = dentry_first_lte(dentry, w->lookup_table); + lte = inode_unnamed_lte(inode, w->lookup_table); if (!lte) return -EIO; - res_entry = <e->resource_entry; - if (res_entry->original_size > 10000) + if (wim_resource_size(lte) > 10000) 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, - buf_len, dentry->reparse_tag); -} - -static int dentry_set_symlink_buf(struct dentry *dentry, - const u8 symlink_buf_hash[]) -{ - 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); - dentry->num_ads = 2; - dentry->ads_entries = ads_entries; - return 0; + u8 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, inode->reparse_tag); } -int dentry_set_symlink(struct dentry *dentry, const char *target, - struct lookup_table *lookup_table, - struct lookup_table_entry **lte_ret) +/* + * Sets @inode 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 inode_set_symlink(struct inode *inode, const char *target, + struct lookup_table *lookup_table, + struct lookup_table_entry **lte_ret) { 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); if (!symlink_buf) 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(); @@ -233,27 +229,28 @@ 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; + copy_hash(lte->hash, symlink_buf_hash); } - ret = dentry_set_symlink_buf(dentry, symlink_buf_hash); - - if (ret != 0) - goto out_free_lte; + inode->lte = lte; + inode->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;