gzip: fix a case where tar xzf fails (we use uninitialized fd)
[oweals/busybox.git] / archival / libunarchive / get_header_cpio.c
index ea0857840d2b10c110dbc4789a0004ce9149f539..3f513551295ceab789f956292a7eef04e4f84c24 100644 (file)
-/*
- *  This program 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 2 of the License, or
- *  (at your option) any later version.
+/* vi: set sw=4 ts=4: */
+/* Copyright 2002 Laurence Anderson
  *
- *  This program 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 Library General Public License for more details.
- *
- *  You should have received a copy of the GNU General Public License
- *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include "unarchive.h"
 #include "libbb.h"
+#include "unarchive.h"
 
 typedef struct hardlinks_s {
-       file_header_t *entry;
+       char *name;
        int inode;
        struct hardlinks_s *next;
 } hardlinks_t;
 
-extern char get_header_cpio(archive_handle_t *archive_handle)
+char get_header_cpio(archive_handle_t *archive_handle)
 {
        static hardlinks_t *saved_hardlinks = NULL;
-       static unsigned short pending_hardlinks = 0;
+       static unsigned pending_hardlinks = 0;
+       static int inode;
+
        file_header_t *file_header = archive_handle->file_header;
        char cpio_header[110];
        int namesize;
        char dummy[16];
-       int major, minor, nlink, inode;
-       char extract_flag;
-       
+       int major, minor, nlink;
+
        if (pending_hardlinks) { /* Deal with any pending hardlinks */
-               hardlinks_t *tmp;
-               hardlinks_t *oldtmp;
+               hardlinks_t *tmp, *oldtmp;
 
                tmp = saved_hardlinks;
                oldtmp = NULL;
 
+               file_header->link_target = file_header->name;
+               file_header->size = 0;
+
                while (tmp) {
-                       error_msg_and_die("need to fix this\n");
-                       if (tmp->entry->link_name) { /* Found a hardlink ready to be extracted */
-                               file_header = tmp->entry;
-                               if (oldtmp) {
-                                       oldtmp->next = tmp->next; /* Remove item from linked list */
-                               } else {
-                                       saved_hardlinks = tmp->next;
-                               }
-                               free(tmp);
+                       if (tmp->inode != inode) {
+                               tmp = tmp->next;
                                continue;
                        }
+
+                       file_header->name = tmp->name;
+
+                       if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) {
+                               archive_handle->action_data(archive_handle);
+                               archive_handle->action_header(archive_handle->file_header);
+                       }
+
+                       pending_hardlinks--;
+
                        oldtmp = tmp;
                        tmp = tmp->next;
+                       free(oldtmp->name);
+                       free(oldtmp);
+                       if (oldtmp == saved_hardlinks)
+                               saved_hardlinks = tmp;
                }
-               pending_hardlinks = 0; /* No more pending hardlinks, read next file entry */
+
+               file_header->name = file_header->link_target;
+
+               if (pending_hardlinks > 1) {
+                       bb_error_msg("error resolving hardlink: archive made by GNU cpio 2.0-2.2?");
+               }
+
+               /* No more pending hardlinks, read next file entry */
+               pending_hardlinks = 0;
        }
 
        /* There can be padding before archive header */
        data_align(archive_handle, 4);
 
-       if (archive_xread_all_eof(archive_handle, cpio_header, 110) == 0) {
-               return(EXIT_FAILURE);
+       if (archive_xread_all_eof(archive_handle, (unsigned char*)cpio_header, 110) == 0) {
+               return EXIT_FAILURE;
        }
        archive_handle->offset += 110;
 
-       if (strncmp(&cpio_header[0], "07070", 5) != 0) {
-               printf("cpio header is %x-%x-%x-%x-%x\n",
-                       cpio_header[0],
-                       cpio_header[1],
-                       cpio_header[2],
-                       cpio_header[3],
-                       cpio_header[4]);
-               error_msg_and_die("Unsupported cpio format");
-       }
-               
-       if ((cpio_header[5] != '1') && (cpio_header[5] != '2')) {
-               error_msg_and_die("Unsupported cpio format, use newc or crc");
+       if (strncmp(&cpio_header[0], "07070", 5) != 0
+        || (cpio_header[5] != '1' && cpio_header[5] != '2')
+       ) {
+               bb_error_msg_and_die("unsupported cpio format, use newc or crc");
        }
 
        {
-           unsigned long tmpsize;
-           sscanf(cpio_header, "%6c%8x%8x%8x%8x%8x%8lx%8lx%16c%8x%8x%8x%8c",
-                   dummy, &inode, (unsigned int*)&file_header->mode, 
+               unsigned long tmpsize;
+               sscanf(cpio_header, "%6c%8x%8x%8x%8x%8x%8lx%8lx%16c%8x%8x%8x%8c",
+                   dummy, &inode, (unsigned int*)&file_header->mode,
                    (unsigned int*)&file_header->uid, (unsigned int*)&file_header->gid,
                    &nlink, &file_header->mtime, &tmpsize,
                    dummy, &major, &minor, &namesize, dummy);
-           file_header->size = tmpsize;
+               file_header->size = tmpsize;
        }
 
-       file_header->name = (char *) xmalloc(namesize + 1);
-       archive_xread_all(archive_handle, file_header->name, namesize); /* Read in filename */
-       file_header->name[namesize] = '\0';
+       free(file_header->name);
+       file_header->name = xzalloc(namesize + 1);
+       /* Read in filename */
+       xread(archive_handle->src_fd, file_header->name, namesize);
        archive_handle->offset += namesize;
 
        /* Update offset amount and skip padding before file contents */
        data_align(archive_handle, 4);
 
        if (strcmp(file_header->name, "TRAILER!!!") == 0) {
-               printf("%d blocks\n", (int) (archive_handle->offset % 512 ? (archive_handle->offset / 512) + 1 : archive_handle->offset / 512)); /* Always round up */
+               /* Always round up */
+               printf("%d blocks\n", (int) (archive_handle->offset % 512 ?
+                                            archive_handle->offset / 512 + 1 :
+                                            archive_handle->offset / 512
+                                           ));
                if (saved_hardlinks) { /* Bummer - we still have unresolved hardlinks */
                        hardlinks_t *tmp = saved_hardlinks;
                        hardlinks_t *oldtmp = NULL;
                        while (tmp) {
-                               error_msg("%s not created: cannot resolve hardlink", tmp->entry->name);
+                               bb_error_msg("%s not created: cannot resolve hardlink", tmp->name);
                                oldtmp = tmp;
                                tmp = tmp->next;
-                               free (oldtmp->entry->name);
-                               free (oldtmp->entry);
-                               free (oldtmp);
+                               free(oldtmp->name);
+                               free(oldtmp);
                        }
                        saved_hardlinks = NULL;
                        pending_hardlinks = 0;
                }
-               return(EXIT_FAILURE);
+               return EXIT_FAILURE;
        }
 
        if (S_ISLNK(file_header->mode)) {
-               file_header->link_name = (char *) xmalloc(file_header->size + 1);
-               archive_xread_all(archive_handle, file_header->link_name, file_header->size);
-               file_header->link_name[file_header->size] = '\0';
+               file_header->link_target = xzalloc(file_header->size + 1);
+               xread(archive_handle->src_fd, file_header->link_target, file_header->size);
                archive_handle->offset += file_header->size;
                file_header->size = 0; /* Stop possible seeks in future */
+       } else {
+               file_header->link_target = NULL;
        }
        if (nlink > 1 && !S_ISDIR(file_header->mode)) {
                if (file_header->size == 0) { /* Put file on a linked list for later */
                        hardlinks_t *new = xmalloc(sizeof(hardlinks_t));
                        new->next = saved_hardlinks;
                        new->inode = inode;
-                       new->entry = file_header;
+                       /* name current allocated, freed later */
+                       new->name = file_header->name;
+                       file_header->name = NULL;
                        saved_hardlinks = new;
-                       return(EXIT_SUCCESS); // Skip this one
-               } else { /* Found the file with data in */
-                       hardlinks_t *tmp = saved_hardlinks;
-                       pending_hardlinks = 1;
-                       while (tmp) {
-                               if (tmp->inode == inode) {
-                                       tmp->entry->link_name = xstrdup(file_header->name);
-                                       nlink--;
-                               }
-                               tmp = tmp->next;
-                       }
-                       if (nlink > 1) {
-                               error_msg("error resolving hardlink: did you create the archive with GNU cpio 2.0-2.2?");
-                       }
+                       return EXIT_SUCCESS; /* Skip this one */
                }
+               /* Found the file with data in */
+               pending_hardlinks = nlink;
        }
-       file_header->device = (major << 8) | minor;
+       file_header->device = makedev(major, minor);
 
-       extract_flag = FALSE;
        if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) {
-               struct stat statbuf;
-
-               extract_flag = TRUE;
-
-               /* Check if the file already exists */
-               if (lstat (file_header->name, &statbuf) == 0) {
-                       if ((archive_handle->flags & ARCHIVE_EXTRACT_UNCONDITIONAL) || (statbuf.st_mtime < file_header->mtime)) {
-                               /* Remove file if flag set or its older than the file to be extracted */
-                               if (unlink(file_header->name) == -1) {
-                                       perror_msg_and_die("Couldnt remove old file");
-                               }
-                       } else {
-                               if (! archive_handle->flags & ARCHIVE_EXTRACT_QUIET) {
-                                       error_msg("%s not created: newer or same age file exists", file_header->name);
-                               }
-                               extract_flag = FALSE;
-                       }
-               }
-               archive_handle->action_header(file_header);
-       }
-
-       archive_handle->action_header(file_header);
-       if (extract_flag) {
                archive_handle->action_data(archive_handle);
+               archive_handle->action_header(archive_handle->file_header);
        } else {
                data_skip(archive_handle);
        }
+
        archive_handle->offset += file_header->size;
-       return (EXIT_SUCCESS);
-}
 
+       free(file_header->link_target);
+
+       return EXIT_SUCCESS;
+}