Next round of work on ISO9660 support:

* Reference-count the directory data so that
    we don't leak memory.
  * Correctly step through the directory records
    (skipping unrecognized extensions)
  * Use better defaults for file modes
  * Sort directory entries by offset of the end of the file
    rather than the beginning of the file.  This fixes a
    lot of "out-of-order" problems with zero-length files,
    in particular.
  * Style fixes, remove some debug code, add some error messages.
This commit is contained in:
Tim Kientzle 2005-01-03 01:24:13 +00:00
parent 3195113e2a
commit 483e82b86c

View File

@ -128,10 +128,12 @@ struct directory_record {
/* In-memory storage for a directory record. */
struct dir_rec {
struct dir_rec *parent;
int refcount;
unsigned char flags;
uint64_t offset; /* Offset on disk. */
uint64_t size; /* File size in bytes. */
time_t mtime; /* File last modified time. */
mode_t mode;
char name[1]; /* Null-terminated filename. */
};
@ -142,6 +144,10 @@ struct iso9660 {
int bid; /* If non-zero, return this as our bid. */
struct archive_string pathname;
uint64_t previous_offset;
uint64_t previous_size;
struct archive_string previous_pathname;
/* TODO: Make this a heap for fast inserts and deletions. */
struct dir_rec **pending_files;
int pending_files_allocated;
@ -150,8 +156,7 @@ struct iso9660 {
uint64_t current_position;
ssize_t logical_block_size;
off_t entry_offset;
ssize_t entry_padding;
off_t entry_sparse_offset;
ssize_t entry_bytes_remaining;
};
@ -162,9 +167,11 @@ static int archive_read_format_iso9660_read_data(struct archive *,
static int archive_read_format_iso9660_read_header(struct archive *,
struct archive_entry *);
static const char *build_pathname(struct archive_string *, struct dir_rec *);
static void dump_isodirent(FILE *, const struct directory_record *);
static time_t isodate(const void *);
static int isPVD(struct iso9660 *, const char *);
static struct dir_rec *next_entry(struct iso9660 *);
static void release_dirrec(struct iso9660 *, struct dir_rec *);
static int store_pending(struct iso9660 *, struct dir_rec *parent,
const struct directory_record *);
static int toi(const void *p, int n);
@ -227,6 +234,8 @@ archive_read_format_iso9660_bid(struct archive *a)
iso9660->bid = isPVD(iso9660, p);
if (iso9660->bid > 0)
return (iso9660->bid);
if (*p == '\xff') /* End-of-volume-descriptor marker. */
break;
}
/* We didn't find a valid PVD; return a bid of zero. */
@ -270,40 +279,13 @@ archive_read_format_iso9660_read_header(struct archive *a,
dirrec = next_entry(iso9660);
if (dirrec == NULL)
return (ARCHIVE_EOF);
while (dirrec->offset < iso9660->current_position) {
archive_string_empty(&iso9660->pathname);
fprintf(stderr, "\n ** Ignoring out-of-order file `%s' (offset 0x%0x/size %d) current offset 0x%x\n", build_pathname(&iso9660->pathname, dirrec), (unsigned int)dirrec->offset, (int)dirrec->size, (unsigned int)iso9660->current_position);
dirrec = next_entry(iso9660);
if (dirrec == NULL)
return (ARCHIVE_EOF);
}
/* Seek forward to the start of that entry. */
while (iso9660->current_position < dirrec->offset) {
ssize_t step = dirrec->offset - iso9660->current_position;
if (step > iso9660->logical_block_size)
step = iso9660->logical_block_size;
bytes_read = (a->compression_read_ahead)(a, &buff, step);
if (bytes_read <= 0)
return (ARCHIVE_FATAL);
if (bytes_read > step)
bytes_read = step;
iso9660->current_position += bytes_read;
(a->compression_read_consume)(a, bytes_read);
}
iso9660->entry_bytes_remaining = dirrec->size;
iso9660->entry_sparse_offset = 0; /* Offset for sparse-file-aware clients. */
/* Set up the entry structure with information about this entry. */
memset(&st, 0, sizeof(st));
iso9660->entry_bytes_remaining = dirrec->size;
/* The following assumes the logical block size is a power of 2. */
iso9660->entry_padding = (iso9660->logical_block_size - 1 )
& (-iso9660->entry_bytes_remaining);
iso9660->entry_offset = 0;
st.st_mode = 0444;
if (dirrec->flags & 0x02)
st.st_mode |= S_IFDIR;
else
st.st_mode |= S_IFREG;
st.st_mode = dirrec->mode;
st.st_mtime = dirrec->mtime;
st.st_size = iso9660->entry_bytes_remaining;
archive_entry_copy_stat(entry, &st);
@ -311,28 +293,74 @@ archive_read_format_iso9660_read_header(struct archive *a,
archive_entry_set_pathname(entry,
build_pathname(&iso9660->pathname, dirrec));
/* If this entry points to the same data as the previous
* entry, convert this into a hardlink to that entry.
* But don't bother for zero-length files. */
if (dirrec->offset == iso9660->previous_offset
&& dirrec->size == iso9660->previous_size
&& dirrec->size > 0) {
archive_entry_set_hardlink(entry,
iso9660->previous_pathname.s);
iso9660->entry_bytes_remaining = 0;
iso9660->entry_sparse_offset = 0;
release_dirrec(iso9660, dirrec);
return (ARCHIVE_OK);
}
/* If the offset is before our current position, we can't
* seek backwards to extract it, so issue a warning. */
if (dirrec->offset < iso9660->current_position) {
archive_set_error(a, ARCHIVE_ERRNO_MISC,
"Ignoring out-of-order file");
iso9660->entry_bytes_remaining = 0;
iso9660->entry_sparse_offset = 0;
release_dirrec(iso9660, dirrec);
return (ARCHIVE_WARN);
}
/* Seek forward to the start of the entry. */
while (iso9660->current_position < dirrec->offset) {
ssize_t step = dirrec->offset - iso9660->current_position;
if (step > iso9660->logical_block_size)
step = iso9660->logical_block_size;
bytes_read = (a->compression_read_ahead)(a, &buff, step);
if (bytes_read <= 0) {
release_dirrec(iso9660, dirrec);
return (ARCHIVE_FATAL);
}
if (bytes_read > step)
bytes_read = step;
iso9660->current_position += bytes_read;
(a->compression_read_consume)(a, bytes_read);
}
iso9660->previous_size = dirrec->size;
iso9660->previous_offset = dirrec->offset;
archive_strcpy(&iso9660->previous_pathname, iso9660->pathname.s);
/* If this is a directory, read in all of the entries right now. */
if (S_ISDIR(st.st_mode)) {
while(iso9660->entry_bytes_remaining > 0) {
const void *block;
const char *p;
const unsigned char *p;
ssize_t step = iso9660->logical_block_size;
if (step > iso9660->entry_bytes_remaining)
step = iso9660->entry_bytes_remaining;
bytes_read = (a->compression_read_ahead)(a, &block, step);
if (bytes_read < step) {
archive_set_error(a, -1,
archive_set_error(a, ARCHIVE_ERRNO_MISC,
"Failed to read full block when scanning ISO9660 directory list");
release_dirrec(iso9660, dirrec);
return (ARCHIVE_FATAL);
}
if (bytes_read > step)
bytes_read = step;
if (bytes_read > iso9660->entry_bytes_remaining)
bytes_read = iso9660->entry_bytes_remaining;
(a->compression_read_consume)(a, bytes_read);
iso9660->current_position += bytes_read;
iso9660->entry_bytes_remaining -= bytes_read;
for (p = block; *p != 0; p += *p) {
for (p = block;
*p != 0 && p < (const unsigned char *)block + bytes_read;
p += *p) {
const struct directory_record *dr
= (const struct directory_record *)p;
/* Skip '.' entry. */
@ -348,6 +376,7 @@ archive_read_format_iso9660_read_header(struct archive *a,
}
}
release_dirrec(iso9660, dirrec);
return (ARCHIVE_OK);
}
@ -359,35 +388,25 @@ archive_read_format_iso9660_read_data(struct archive *a,
struct iso9660 *iso9660;
iso9660 = *(a->pformat_data);
if (iso9660->entry_bytes_remaining > 0) {
bytes_read = (a->compression_read_ahead)(a, buff, 1);
if (bytes_read <= 0)
return (ARCHIVE_FATAL);
if (bytes_read > iso9660->entry_bytes_remaining)
bytes_read = iso9660->entry_bytes_remaining;
*size = bytes_read;
*offset = iso9660->entry_offset;
iso9660->entry_offset += bytes_read;
iso9660->entry_bytes_remaining -= bytes_read;
iso9660->current_position += bytes_read;
(a->compression_read_consume)(a, bytes_read);
return (ARCHIVE_OK);
} else {
while (iso9660->entry_padding > 0) {
bytes_read = (a->compression_read_ahead)(a, buff, 1);
if (bytes_read <= 0)
return (ARCHIVE_FATAL);
if (bytes_read > iso9660->entry_padding)
bytes_read = iso9660->entry_padding;
iso9660->current_position += bytes_read;
(a->compression_read_consume)(a, bytes_read);
iso9660->entry_padding -= bytes_read;
}
if (iso9660->entry_bytes_remaining <= 0) {
*buff = NULL;
*size = 0;
*offset = iso9660->entry_offset;
*offset = iso9660->entry_sparse_offset;
return (ARCHIVE_EOF);
}
bytes_read = (a->compression_read_ahead)(a, buff, 1);
if (bytes_read <= 0)
return (ARCHIVE_FATAL);
if (bytes_read > iso9660->entry_bytes_remaining)
bytes_read = iso9660->entry_bytes_remaining;
*size = bytes_read;
*offset = iso9660->entry_sparse_offset;
iso9660->entry_sparse_offset += bytes_read;
iso9660->entry_bytes_remaining -= bytes_read;
iso9660->current_position += bytes_read;
(a->compression_read_consume)(a, bytes_read);
return (ARCHIVE_OK);
}
static int
@ -424,6 +443,9 @@ store_pending(struct iso9660 *iso9660, struct dir_rec *parent,
new_dirent = malloc(sizeof(*new_dirent) + isodirent->name_len[0] + 1);
new_dirent->parent = parent;
if (parent != NULL)
parent->refcount++;
new_dirent->refcount = 0;
new_dirent->flags = isodirent->flags[0];
new_dirent->offset = toi(isodirent->extent, 4)
* iso9660->logical_block_size;
@ -432,45 +454,80 @@ store_pending(struct iso9660 *iso9660, struct dir_rec *parent,
memcpy(new_dirent->name, isodirent->name, isodirent->name_len[0]);
new_dirent->name[(int)isodirent->name_len[0]] = '\0';
if (isodirent->flags[0] & 0x02)
new_dirent->mode = S_IFDIR | 0700;
else
new_dirent->mode = S_IFREG | 0400;
iso9660->pending_files[iso9660->pending_files_used++] = new_dirent;
/* DEBUGGING */
/* DEBUGGING: Warn about attributes I don't yet fully support. */
if ((isodirent->flags[0] & ~0x02) != 0) {
archive_string_empty(&iso9660->pathname);
fprintf(stderr, "\n ** Unrecognized flag 0x%x in file %s\n",
new_dirent->flags,
build_pathname(&iso9660->pathname, new_dirent));
fprintf(stderr, "\n ** Unrecognized flag: ");
dump_isodirent(stderr, isodirent);
fprintf(stderr, "\n");
} else if (toi(isodirent->volume_sequence_number, 2) != 1) {
fprintf(stderr, "\n ** Unrecognized sequence number: ");
dump_isodirent(stderr, isodirent);
fprintf(stderr, "\n");
} else if (isodirent->file_unit_size[0] != 0) {
fprintf(stderr, "\n ** Unexpected file unit size: ");
dump_isodirent(stderr, isodirent);
fprintf(stderr, "\n");
} else if (isodirent->interleave[0] != 0) {
fprintf(stderr, "\n ** Unexpected interleave: ");
dump_isodirent(stderr, isodirent);
fprintf(stderr, "\n");
} else if (isodirent->ext_attr_length[0] != 0) {
fprintf(stderr, "\n ** Unexpected extended attribute length: ");
dump_isodirent(stderr, isodirent);
fprintf(stderr, "\n");
}
if (toi(isodirent->volume_sequence_number,2) != 1
|| isodirent->file_unit_size[0] != 0
|| isodirent->interleave[0] != 0
|| isodirent->ext_attr_length[0] != 0) {
fprintf(stderr, "\n ** Unhandled ISO9660 directory attribute:");
fprintf(stderr, " l %d, a %d, ext 0x%x, s %d, f 0x%02x, unt %d, ilv %d, seq %d: `%.*s' (%d)\n", isodirent->length[0], isodirent->ext_attr_length[0], toi(isodirent->extent, 4) * 2048, toi(isodirent->size, 4), isodirent->flags[0], isodirent->file_unit_size[0], isodirent->interleave[0], toi(isodirent->volume_sequence_number,2), isodirent->name_len[0], isodirent->name, isodirent->name_len[0]);
}
return (ARCHIVE_OK);
}
static void
release_dirrec(struct iso9660 *iso9660, struct dir_rec *dr)
{
struct dir_rec *parent;
if (dr->refcount == 0) {
dr->flags = 0xff;
parent = dr->parent;
free(dr);
if (parent != NULL) {
parent->refcount--;
release_dirrec(iso9660, parent);
}
}
}
static struct dir_rec *
next_entry(struct iso9660 *iso9660)
{
int least_index = 0;
uint64_t least_offset = iso9660->pending_files[0]->offset;
int least_index;
uint64_t least_end_offset;
int i;
struct dir_rec *r;
if (iso9660->pending_files_used < 1)
return (NULL);
/* Assume the first file in the list is the earliest on disk. */
least_index = 0;
least_end_offset = iso9660->pending_files[0]->offset
+ iso9660->pending_files[0]->size;
/* Now, try to find an earlier one. */
for(i = 0; i < iso9660->pending_files_used; i++) {
if (iso9660->pending_files[i]->offset < least_offset) {
least_offset = iso9660->pending_files[i]->offset;
/* Use the position of the file *end* as our comparison. */
uint64_t end_offset = iso9660->pending_files[i]->offset
+ iso9660->pending_files[i]->size;
if (least_end_offset > end_offset) {
least_index = i;
least_end_offset = end_offset;
}
}
r = iso9660->pending_files[least_index];
@ -504,8 +561,8 @@ isodate(const void *p)
tm.tm_sec = v[5];
/* v[6] is the timezone offset, in 1/4-hour increments. */
offset = ((const signed char *)p)[6];
tm.tm_hour += offset / 4;
tm.tm_min += (offset % 4) * 15;
tm.tm_hour -= offset / 4;
tm.tm_min -= (offset % 4) * 15;
return (timegm(&tm));
}
@ -519,3 +576,18 @@ build_pathname(struct archive_string *as, struct dir_rec *dr)
archive_strcat(as, dr->name);
return (as->s);
}
static void
dump_isodirent(FILE *out, const struct directory_record *isodirent)
{
fprintf(out, " l %d,", isodirent->length[0]);
fprintf(out, " a %d,", isodirent->ext_attr_length[0]);
fprintf(out, " ext 0x%x,", toi(isodirent->extent, 4));
fprintf(out, " s %d,", toi(isodirent->size, 4));
fprintf(out, " f 0x%02x,", isodirent->flags[0]);
fprintf(out, " u %d,", isodirent->file_unit_size[0]);
fprintf(out, " ilv %d,", isodirent->interleave[0]);
fprintf(out, " seq %d,", toi(isodirent->volume_sequence_number,2));
fprintf(out, " nl %d:", isodirent->name_len[0]);
fprintf(out, " `%.*s'", isodirent->name_len[0], isodirent->name);
}