diff options
Diffstat (limited to 'archival/libarchive/get_header_cpio.c')
| -rw-r--r-- | archival/libarchive/get_header_cpio.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/archival/libarchive/get_header_cpio.c b/archival/libarchive/get_header_cpio.c new file mode 100644 index 0000000..3d99b49 --- /dev/null +++ b/archival/libarchive/get_header_cpio.c @@ -0,0 +1,186 @@ +/* vi: set sw=4 ts=4: */ +/* Copyright 2002 Laurence Anderson + * + * Licensed under GPLv2 or later, see file LICENSE in this source tree. + */ + +#include "libbb.h" +#include "archive.h" + +typedef struct hardlinks_t { + struct hardlinks_t *next; + int inode; /* TODO: must match maj/min too! */ + int mode ; + int mtime; /* These three are useful only in corner case */ + int uid ; /* of hardlinks with zero size body */ + int gid ; + char name[1]; +} hardlinks_t; + +char FAST_FUNC get_header_cpio(archive_handle_t *archive_handle) +{ + file_header_t *file_header = archive_handle->file_header; + char cpio_header[110]; + int namesize; + int major, minor, nlink, mode, inode; + unsigned size, uid, gid, mtime; + + /* There can be padding before archive header */ + data_align(archive_handle, 4); + + size = full_read(archive_handle->src_fd, cpio_header, 110); + if (size == 0) { + goto create_hardlinks; + } + if (size != 110) { + bb_error_msg_and_die("short read"); + } + archive_handle->offset += 110; + + 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"); + } + + if (sscanf(cpio_header + 6, + "%8x" "%8x" "%8x" "%8x" + "%8x" "%8x" "%8x" /*maj,min:*/ "%*16c" + /*rmaj,rmin:*/"%8x" "%8x" "%8x" /*chksum: "%*8c"*/, + &inode, &mode, &uid, &gid, + &nlink, &mtime, &size, + &major, &minor, &namesize) != 10) + bb_error_msg_and_die("damaged cpio file"); + file_header->mode = mode; + file_header->uid = uid; + file_header->gid = gid; + file_header->mtime = mtime; + file_header->size = size; + + namesize &= 0x1fff; /* paranoia: limit names to 8k chars */ + file_header->name = xzalloc(namesize + 1); + /* Read in filename */ + xread(archive_handle->src_fd, file_header->name, namesize); + if (file_header->name[0] == '/') { + /* Testcase: echo /etc/hosts | cpio -pvd /tmp + * Without this code, it tries to unpack /etc/hosts + * into "/etc/hosts", not "etc/hosts". + */ + char *p = file_header->name; + do p++; while (*p == '/'); + overlapping_strcpy(file_header->name, p); + } + 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) { + /* Always round up. ">> 9" divides by 512 */ + archive_handle->cpio__blocks = (uoff_t)(archive_handle->offset + 511) >> 9; + goto create_hardlinks; + } + + file_header->link_target = NULL; + if (S_ISLNK(file_header->mode)) { + file_header->size &= 0x1fff; /* paranoia: limit names to 8k chars */ + 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 */ + } + +// TODO: data_extract_all can't deal with hardlinks to non-files... +// when fixed, change S_ISREG to !S_ISDIR here + + if (nlink > 1 && S_ISREG(file_header->mode)) { + hardlinks_t *new = xmalloc(sizeof(*new) + namesize); + new->inode = inode; + new->mode = mode ; + new->mtime = mtime; + new->uid = uid ; + new->gid = gid ; + strcpy(new->name, file_header->name); + /* Put file on a linked list for later */ + if (size == 0) { + new->next = archive_handle->cpio__hardlinks_to_create; + archive_handle->cpio__hardlinks_to_create = new; + return EXIT_SUCCESS; /* Skip this one */ + /* TODO: this breaks cpio -t (it does not show hardlinks) */ + } + new->next = archive_handle->cpio__created_hardlinks; + archive_handle->cpio__created_hardlinks = new; + } + file_header->device = makedev(major, minor); + + if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) { + archive_handle->action_data(archive_handle); +//TODO: run "echo /etc/hosts | cpio -pv /tmp" twice. On 2nd run: +//cpio: etc/hosts not created: newer or same age file exists +//etc/hosts <-- should NOT show it +//2 blocks <-- should say "0 blocks" + archive_handle->action_header(file_header); + } else { + data_skip(archive_handle); + } + + archive_handle->offset += file_header->size; + + free(file_header->link_target); + free(file_header->name); + file_header->link_target = NULL; + file_header->name = NULL; + + return EXIT_SUCCESS; + + create_hardlinks: + free(file_header->link_target); + free(file_header->name); + + while (archive_handle->cpio__hardlinks_to_create) { + hardlinks_t *cur; + hardlinks_t *make_me = archive_handle->cpio__hardlinks_to_create; + + archive_handle->cpio__hardlinks_to_create = make_me->next; + + memset(file_header, 0, sizeof(*file_header)); + file_header->mtime = make_me->mtime; + file_header->name = make_me->name; + file_header->mode = make_me->mode; + file_header->uid = make_me->uid; + file_header->gid = make_me->gid; + /*file_header->size = 0;*/ + /*file_header->link_target = NULL;*/ + + /* Try to find a file we are hardlinked to */ + cur = archive_handle->cpio__created_hardlinks; + while (cur) { + /* TODO: must match maj/min too! */ + if (cur->inode == make_me->inode) { + file_header->link_target = cur->name; + /* link_target != NULL, size = 0: "I am a hardlink" */ + if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) + archive_handle->action_data(archive_handle); + free(make_me); + goto next_link; + } + cur = cur->next; + } + /* Oops... no file with such inode was created... do it now + * (happens when hardlinked files are empty (zero length)) */ + if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) + archive_handle->action_data(archive_handle); + /* Move to the list of created hardlinked files */ + make_me->next = archive_handle->cpio__created_hardlinks; + archive_handle->cpio__created_hardlinks = make_me; + next_link: ; + } + + while (archive_handle->cpio__created_hardlinks) { + hardlinks_t *p = archive_handle->cpio__created_hardlinks; + archive_handle->cpio__created_hardlinks = p->next; + free(p); + } + + return EXIT_FAILURE; /* "No more files to process" */ +} |