More -Wwrite-strings cleanup and make sure you can actually play it.

[dragonfly.git] / contrib / libarchive / archive_read_support_format_cpio.c

/*-
 * Copyright (c) 2003-2004 Tim Kientzle
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer
 *    in this position and unchanged.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "archive_platform.h"
__FBSDID("$FreeBSD: src/lib/libarchive/archive_read_support_format_cpio.c,v 1.13 2005/04/06 04:19:30 kientzle Exp $");

#include <sys/stat.h>

#include <errno.h>
/* #include <stdint.h> */ /* See archive_platform.h */
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "archive.h"
#include "archive_entry.h"
#include "archive_private.h"

struct cpio_bin_header {
        unsigned char   c_magic[2];
        unsigned char   c_dev[2];
        unsigned char   c_ino[2];
        unsigned char   c_mode[2];
        unsigned char   c_uid[2];
        unsigned char   c_gid[2];
        unsigned char   c_nlink[2];
        unsigned char   c_rdev[2];
        unsigned char   c_mtime[4];
        unsigned char   c_namesize[2];
        unsigned char   c_filesize[4];
};

struct cpio_odc_header {
        char    c_magic[6];
        char    c_dev[6];
        char    c_ino[6];
        char    c_mode[6];
        char    c_uid[6];
        char    c_gid[6];
        char    c_nlink[6];
        char    c_rdev[6];
        char    c_mtime[11];
        char    c_namesize[6];
        char    c_filesize[11];
};

struct cpio_newc_header {
        char    c_magic[6];
        char    c_ino[8];
        char    c_mode[8];
        char    c_uid[8];
        char    c_gid[8];
        char    c_nlink[8];
        char    c_mtime[8];
        char    c_filesize[8];
        char    c_devmajor[8];
        char    c_devminor[8];
        char    c_rdevmajor[8];
        char    c_rdevminor[8];
        char    c_namesize[8];
        char    c_crc[8];
};

struct links_entry {
        struct links_entry      *next;
        struct links_entry      *previous;
        int                      links;
        dev_t                    dev;
        ino_t                    ino;
        char                    *name;
};

#define CPIO_MAGIC   0x13141516
struct cpio {
        int                       magic;
        int                     (*read_header)(struct archive *, struct cpio *,
                                     struct stat *, size_t *, size_t *);
        struct links_entry       *links_head;
        struct archive_string     entry_name;
        struct archive_string     entry_linkname;
        off_t                     entry_bytes_remaining;
        off_t                     entry_offset;
        off_t                     entry_padding;
};

static int64_t  atol16(const char *, unsigned);
static int64_t  atol8(const char *, unsigned);
static int      archive_read_format_cpio_bid(struct archive *);
static int      archive_read_format_cpio_cleanup(struct archive *);
static int      archive_read_format_cpio_read_data(struct archive *,
                    const void **, size_t *, off_t *);
static int      archive_read_format_cpio_read_header(struct archive *,
                    struct archive_entry *);
static int      be4(const unsigned char *);
static int      header_bin_be(struct archive *, struct cpio *, struct stat *,
                    size_t *, size_t *);
static int      header_bin_le(struct archive *, struct cpio *, struct stat *,
                    size_t *, size_t *);
static int      header_newc(struct archive *, struct cpio *, struct stat *,
                    size_t *, size_t *);
static int      header_odc(struct archive *, struct cpio *, struct stat *,
                    size_t *, size_t *);
static int      le4(const unsigned char *);
static void     record_hardlink(struct cpio *cpio, struct archive_entry *entry,
                    const struct stat *st);

int
archive_read_support_format_cpio(struct archive *a)
{
        struct cpio *cpio;
        int r;

        cpio = malloc(sizeof(*cpio));
        memset(cpio, 0, sizeof(*cpio));
        cpio->magic = CPIO_MAGIC;

        r = __archive_read_register_format(a,
            cpio,
            archive_read_format_cpio_bid,
            archive_read_format_cpio_read_header,
            archive_read_format_cpio_read_data,
            NULL,
            archive_read_format_cpio_cleanup);

        if (r != ARCHIVE_OK)
                free(cpio);
        return (ARCHIVE_OK);
}


static int
archive_read_format_cpio_bid(struct archive *a)
{
        int bid, bytes_read;
        const void *h;
        const unsigned char *p;
        struct cpio *cpio;

        cpio = *(a->pformat_data);
        bid = 0;
        bytes_read = (a->compression_read_ahead)(a, &h, 6);
        /* Convert error code into error return. */
        if (bytes_read < 0)
                return ((int)bytes_read);
        if (bytes_read < 6)
                return (-1);

        p = h;
        if (memcmp(p, "070707", 6) == 0) {
                /* ASCII cpio archive (odc, POSIX.1) */
                cpio->read_header = header_odc;
                bid += 48;
                /*
                 * XXX TODO:  More verification; Could check that only octal
                 * digits appear in appropriate header locations. XXX
                 */
        } else if (memcmp(p, "070701", 6) == 0) {
                /* ASCII cpio archive (SVR4 without CRC) */
                cpio->read_header = header_newc;
                bid += 48;
                /*
                 * XXX TODO:  More verification; Could check that only hex
                 * digits appear in appropriate header locations. XXX
                 */
        } else if (memcmp(p, "070702", 6) == 0) {
                /* ASCII cpio archive (SVR4 with CRC) */
                /* XXX TODO: Flag that we should check the CRC. XXX */
                cpio->read_header = header_newc;
                bid += 48;
                /*
                 * XXX TODO:  More verification; Could check that only hex
                 * digits appear in appropriate header locations. XXX
                 */
        } else if (p[0] * 256 + p[1] == 070707) {
                /* big-endian binary cpio archives */
                cpio->read_header = header_bin_be;
                bid += 16;
                /* Is more verification possible here? */
        } else if (p[0] + p[1] * 256 == 070707) {
                /* little-endian binary cpio archives */
                cpio->read_header = header_bin_le;
                bid += 16;
                /* Is more verification possible here? */
        } else
                return (ARCHIVE_WARN);

        return (bid);
}

static int
archive_read_format_cpio_read_header(struct archive *a,
    struct archive_entry *entry)
{
        struct stat st;
        struct cpio *cpio;
        size_t bytes;
        const void *h;
        size_t namelength;
        size_t name_pad;
        int r;

        memset(&st, 0, sizeof(st));

        cpio = *(a->pformat_data);
        r = (cpio->read_header(a, cpio, &st, &namelength, &name_pad));

        if (r != ARCHIVE_OK)
                return (r);

        /* Assign all of the 'stat' fields at once. */
        archive_entry_copy_stat(entry, &st);

        /* Read name from buffer. */
        bytes = (a->compression_read_ahead)(a, &h, namelength + name_pad);
        if (bytes < namelength + name_pad)
            return (ARCHIVE_FATAL);
        (a->compression_read_consume)(a, namelength + name_pad);
        archive_strncpy(&cpio->entry_name, h, namelength);
        archive_entry_set_pathname(entry, cpio->entry_name.s);
        cpio->entry_offset = 0;

        /* If this is a symlink, read the link contents. */
        if (S_ISLNK(st.st_mode)) {
                bytes = (a->compression_read_ahead)(a, &h,
                    cpio->entry_bytes_remaining);
                if ((off_t)bytes < cpio->entry_bytes_remaining)
                        return (ARCHIVE_FATAL);
                (a->compression_read_consume)(a, cpio->entry_bytes_remaining);
                archive_strncpy(&cpio->entry_linkname, h,
                    cpio->entry_bytes_remaining);
                archive_entry_set_symlink(entry, cpio->entry_linkname.s);
                cpio->entry_bytes_remaining = 0;
        }

        /* Compare name to "TRAILER!!!" to test for end-of-archive. */
        if (namelength == 11 && strcmp(h,"TRAILER!!!")==0) {
            /* TODO: Store file location of start of block. */
            archive_set_error(a, 0, NULL);
            return (ARCHIVE_EOF);
        }

        /* Detect and record hardlinks to previously-extracted entries. */
        record_hardlink(cpio, entry, &st);

        return (ARCHIVE_OK);
}

static int
archive_read_format_cpio_read_data(struct archive *a,
    const void **buff, size_t *size, off_t *offset)
{
        ssize_t bytes_read;
        struct cpio *cpio;

        cpio = *(a->pformat_data);
        if (cpio->entry_bytes_remaining > 0) {
                bytes_read = (a->compression_read_ahead)(a, buff, 1);
                if (bytes_read <= 0)
                        return (ARCHIVE_FATAL);
                if (bytes_read > cpio->entry_bytes_remaining)
                        bytes_read = cpio->entry_bytes_remaining;
                *size = bytes_read;
                *offset = cpio->entry_offset;
                cpio->entry_offset += bytes_read;
                cpio->entry_bytes_remaining -= bytes_read;
                (a->compression_read_consume)(a, bytes_read);
                return (ARCHIVE_OK);
        } else {
                while (cpio->entry_padding > 0) {
                        bytes_read = (a->compression_read_ahead)(a, buff, 1);
                        if (bytes_read <= 0)
                                return (ARCHIVE_FATAL);
                        if (bytes_read > cpio->entry_padding)
                                bytes_read = cpio->entry_padding;
                        (a->compression_read_consume)(a, bytes_read);
                        cpio->entry_padding -= bytes_read;
                }
                *buff = NULL;
                *size = 0;
                *offset = cpio->entry_offset;
                return (ARCHIVE_EOF);
        }
}

static int
header_newc(struct archive *a, struct cpio *cpio, struct stat *st,
    size_t *namelength, size_t *name_pad)
{
        const void *h;
        const struct cpio_newc_header *header;
        size_t bytes;

        a->archive_format = ARCHIVE_FORMAT_CPIO;
        a->archive_format_name = "ASCII cpio (SVR4 with no CRC)";

        /* Read fixed-size portion of header. */
        bytes = (a->compression_read_ahead)(a, &h, sizeof(struct cpio_newc_header));
        if (bytes < sizeof(struct cpio_newc_header))
            return (ARCHIVE_FATAL);
        (a->compression_read_consume)(a, sizeof(struct cpio_newc_header));

        /* Parse out hex fields into struct stat. */
        header = h;
        st->st_ino = atol16(header->c_ino, sizeof(header->c_ino));
        st->st_mode = atol16(header->c_mode, sizeof(header->c_mode));
        st->st_uid = atol16(header->c_uid, sizeof(header->c_uid));
        st->st_gid = atol16(header->c_gid, sizeof(header->c_gid));
        st->st_nlink = atol16(header->c_nlink, sizeof(header->c_nlink));
        st->st_mtime = atol16(header->c_mtime, sizeof(header->c_mtime));
        *namelength = atol16(header->c_namesize, sizeof(header->c_namesize));
        /* Pad name to 2 more than a multiple of 4. */
        *name_pad = (2 - *namelength) & 3;

        /*
         * Note: entry_bytes_remaining is at least 64 bits and
         * therefore gauranteed to be big enough for a 33-bit file
         * size.  struct stat.st_size may only be 32 bits, so
         * assigning there first could lose information.
         */
        cpio->entry_bytes_remaining =
            atol16(header->c_filesize, sizeof(header->c_filesize));
        st->st_size = cpio->entry_bytes_remaining;
        /* Pad file contents to a multiple of 4. */
        cpio->entry_padding = 3 & -cpio->entry_bytes_remaining;
        return (ARCHIVE_OK);
}

static int
header_odc(struct archive *a, struct cpio *cpio, struct stat *st,
    size_t *namelength, size_t *name_pad)
{
        const void *h;
        const struct cpio_odc_header *header;
        size_t bytes;

        a->archive_format = ARCHIVE_FORMAT_CPIO;
        a->archive_format_name = "POSIX octet-oriented cpio";

        /* Read fixed-size portion of header. */
        bytes = (a->compression_read_ahead)(a, &h, sizeof(struct cpio_odc_header));
        if (bytes < sizeof(struct cpio_odc_header))
            return (ARCHIVE_FATAL);
        (a->compression_read_consume)(a, sizeof(struct cpio_odc_header));

        /* Parse out octal fields into struct stat. */
        header = h;

        st->st_dev = atol8(header->c_dev, sizeof(header->c_dev));
        st->st_ino = atol8(header->c_ino, sizeof(header->c_ino));
        st->st_mode = atol8(header->c_mode, sizeof(header->c_mode));
        st->st_uid = atol8(header->c_uid, sizeof(header->c_uid));
        st->st_gid = atol8(header->c_gid, sizeof(header->c_gid));
        st->st_nlink = atol8(header->c_nlink, sizeof(header->c_nlink));
        st->st_rdev = atol8(header->c_rdev, sizeof(header->c_rdev));
        st->st_mtime = atol8(header->c_mtime, sizeof(header->c_mtime));
        *namelength = atol8(header->c_namesize, sizeof(header->c_namesize));
        *name_pad = 0; /* No padding of filename. */

        /*
         * Note: entry_bytes_remaining is at least 64 bits and
         * therefore gauranteed to be big enough for a 33-bit file
         * size.  struct stat.st_size may only be 32 bits, so
         * assigning there first could lose information.
         */
        cpio->entry_bytes_remaining =
            atol8(header->c_filesize, sizeof(header->c_filesize));
        st->st_size = cpio->entry_bytes_remaining;
        cpio->entry_padding = 0;
        return (ARCHIVE_OK);
}

static int
header_bin_le(struct archive *a, struct cpio *cpio, struct stat *st,
    size_t *namelength, size_t *name_pad)
{
        const void *h;
        const struct cpio_bin_header *header;
        size_t bytes;

        a->archive_format = ARCHIVE_FORMAT_CPIO;
        a->archive_format_name = "cpio (little-endian binary)";

        /* Read fixed-size portion of header. */
        bytes = (a->compression_read_ahead)(a, &h, sizeof(struct cpio_bin_header));
        if (bytes < sizeof(struct cpio_bin_header))
            return (ARCHIVE_FATAL);
        (a->compression_read_consume)(a, sizeof(struct cpio_bin_header));

        /* Parse out binary fields into struct stat. */
        header = h;

        st->st_dev = header->c_dev[0] + header->c_dev[1] * 256;
        st->st_ino = header->c_ino[0] + header->c_ino[1] * 256;
        st->st_mode = header->c_mode[0] + header->c_mode[1] * 256;
        st->st_uid = header->c_uid[0] + header->c_uid[1] * 256;
        st->st_gid = header->c_gid[0] + header->c_gid[1] * 256;
        st->st_nlink = header->c_nlink[0] + header->c_nlink[1] * 256;
        st->st_rdev = header->c_rdev[0] + header->c_rdev[1] * 256;
        st->st_mtime = le4(header->c_mtime);
        *namelength = header->c_namesize[0] + header->c_namesize[1] * 256;
        *name_pad = *namelength & 1; /* Pad to even. */

        cpio->entry_bytes_remaining = le4(header->c_filesize);
        st->st_size = cpio->entry_bytes_remaining;
        cpio->entry_padding = cpio->entry_bytes_remaining & 1; /* Pad to even. */
        return (ARCHIVE_OK);
}

static int
header_bin_be(struct archive *a, struct cpio *cpio, struct stat *st,
    size_t *namelength, size_t *name_pad)
{
        const void *h;
        const struct cpio_bin_header *header;
        size_t bytes;

        a->archive_format = ARCHIVE_FORMAT_CPIO;
        a->archive_format_name = "cpio (big-endian binary)";

        /* Read fixed-size portion of header. */
        bytes = (a->compression_read_ahead)(a, &h,
            sizeof(struct cpio_bin_header));
        if (bytes < sizeof(struct cpio_bin_header))
            return (ARCHIVE_FATAL);
        (a->compression_read_consume)(a, sizeof(struct cpio_bin_header));

        /* Parse out binary fields into struct stat. */
        header = h;
        st->st_dev = header->c_dev[0] * 256 + header->c_dev[1];
        st->st_ino = header->c_ino[0] * 256 + header->c_ino[1];
        st->st_mode = header->c_mode[0] * 256 + header->c_mode[1];
        st->st_uid = header->c_uid[0] * 256 + header->c_uid[1];
        st->st_gid = header->c_gid[0] * 256 + header->c_gid[1];
        st->st_nlink = header->c_nlink[0] * 256 + header->c_nlink[1];
        st->st_rdev = header->c_rdev[0] * 256 + header->c_rdev[1];
        st->st_mtime = be4(header->c_mtime);
        *namelength = header->c_namesize[0] * 256 + header->c_namesize[1];
        *name_pad = *namelength & 1; /* Pad to even. */

        cpio->entry_bytes_remaining = be4(header->c_filesize);
        st->st_size = cpio->entry_bytes_remaining;
        cpio->entry_padding = cpio->entry_bytes_remaining & 1; /* Pad to even. */
        return (ARCHIVE_OK);
}

static int
archive_read_format_cpio_cleanup(struct archive *a)
{
        struct cpio *cpio;

        cpio = *(a->pformat_data);
        /* Free inode->name map */
        while (cpio->links_head != NULL) {
                struct links_entry *lp = cpio->links_head->next;

                if (cpio->links_head->name)
                        free(cpio->links_head->name);
                free(cpio->links_head);
                cpio->links_head = lp;
        }

        free(cpio);
        *(a->pformat_data) = NULL;
        return (ARCHIVE_OK);
}

static int
le4(const unsigned char *p)
{
        return ((p[0]<<16) + (p[1]<<24) + (p[2]<<0) + (p[3]<<8));
}


static int
be4(const unsigned char *p)
{
        return (p[0] + (p[1]<<8) + (p[2]<<16) + (p[3]<<24));
}

/*
 * Note that this implementation does not (and should not!) obey
 * locale settings; you cannot simply substitute strtol here, since
 * it does obey locale.
 */
static int64_t
atol8(const char *p, unsigned char_cnt)
{
        int64_t l;
        int digit;

        l = 0;
        while (char_cnt-- > 0) {
                if (*p >= '0' && *p <= '7')
                        digit = *p - '0';
                else
                        return (l);
                p++;
                l <<= 3;
                l |= digit;
        }
        return (l);
}

static int64_t
atol16(const char *p, unsigned char_cnt)
{
        int64_t l;
        int digit;

        l = 0;
        while (char_cnt-- > 0) {
                if (*p >= 'a' && *p <= 'f')
                        digit = *p - 'a' + 10;
                else if (*p >= 'A' && *p <= 'F')
                        digit = *p - 'A' + 10;
                else if (*p >= '0' && *p <= '9')
                        digit = *p - '0';
                else
                        return (l);
                p++;
                l <<= 4;
                l |= digit;
        }
        return (l);
}

static void
record_hardlink(struct cpio *cpio, struct archive_entry *entry,
    const struct stat *st)
{
        struct links_entry      *le;

        /*
         * First look in the list of multiply-linked files.  If we've
         * already dumped it, convert this entry to a hard link entry.
         */
        for (le = cpio->links_head; le; le = le->next) {
                if (le->dev == st->st_dev && le->ino == st->st_ino) {
                        archive_entry_set_hardlink(entry, le->name);

                        if (--le->links <= 0) {
                                if (le->previous != NULL)
                                        le->previous->next = le->next;
                                if (le->next != NULL)
                                        le->next->previous = le->previous;
                                if (cpio->links_head == le)
                                        cpio->links_head = le->next;
                                free(le);
                        }

                        return;
                }
        }

        le = malloc(sizeof(struct links_entry));
        if (cpio->links_head != NULL)
                cpio->links_head->previous = le;
        le->next = cpio->links_head;
        le->previous = NULL;
        cpio->links_head = le;
        le->dev = st->st_dev;
        le->ino = st->st_ino;
        le->links = st->st_nlink - 1;
        le->name = strdup(archive_entry_pathname(entry));
}