/*
* Return a new initialized jzentry corresponding to a given hash cell.
* In case of error, returns NULL.
* We already sanity-checked all the CEN headers for ZIP format errors
* in readCEN(), so we don't check them again here.
* The ZIP lock should be held here.
*/
static jzentry *
newEntry(jzfile *zip, jzcell *zc, AccessHint accessHint)
{
jlong locoff;
jint nlen, elen, clen;
jzentry *ze;
char *cen;
if ((ze = (jzentry *) malloc(sizeof(jzentry))) == NULL) return NULL;
ze->name = NULL;
ze->extra = NULL;
ze->comment = NULL;
#ifdef USE_MMAP
if (zip->usemmap) {
cen = (char*) zip->maddr + zc->cenpos - zip->offset;
} else
#endif
{
if (accessHint == ACCESS_RANDOM)
cen = readCENHeader(zip, zc->cenpos, AMPLE_CEN_HEADER_SIZE);
else
cen = sequentialAccessReadCENHeader(zip, zc->cenpos);
if (cen == NULL) goto Catch;
}
nlen = CENNAM(cen);
elen = CENEXT(cen);
clen = CENCOM(cen);
ze->time = CENTIM(cen);
ze->size = CENLEN(cen);
ze->csize = (CENHOW(cen) == STORED) ? 0 : CENSIZ(cen);
ze->crc = CENCRC(cen);
locoff = CENOFF(cen);
ze->pos = -(zip->locpos + locoff);
ze->flag = CENFLG(cen);
if ((ze->name = malloc(nlen + 1)) == NULL) goto Catch;
memcpy(ze->name, cen + CENHDR, nlen);
ze->name[nlen] = '\0';
if (elen > 0) {
char *extra = cen + CENHDR + nlen;
/* This entry has "extra" data */
if ((ze->extra = malloc(elen + 2)) == NULL) goto Catch;
ze->extra[0] = (unsigned char) elen;
ze->extra[1] = (unsigned char) (elen >> 8);
memcpy(ze->extra+2, extra, elen);
if (ze->csize == ZIP64_MAGICVAL || ze->size == ZIP64_MAGICVAL ||
locoff == ZIP64_MAGICVAL) {
jint off = 0;
while ((off + 4) < elen) { // spec: HeaderID+DataSize+Data
jint sz = SH(extra, off + 2);
if (SH(extra, off) == ZIP64_EXTID) {
off += 4;
if (ze->size == ZIP64_MAGICVAL) {
// if invalid zip64 extra fields, just skip
if (sz < 8 || (off + 8) > elen)
break;
ze->size = LL(extra, off);
sz -= 8;
off += 8;
}
if (ze->csize == ZIP64_MAGICVAL) {
if (sz < 8 || (off + 8) > elen)
break;
ze->csize = LL(extra, off);
sz -= 8;
off += 8;
}
if (locoff == ZIP64_MAGICVAL) {
if (sz < 8 || (off + 8) > elen)
break;
ze->pos = -(zip->locpos + LL(extra, off));
sz -= 8;
off += 8;
}
break;
}
off += (sz + 4);
}
}
}
/*
* Reads zip file central directory. Returns the file position of first
* CEN header, otherwise returns -1 if an error occured. If zip->msg != NULL
* then the error was a zip format error and zip->msg has the error text.
* Always pass in -1 for knownTotal; it's used for a recursive call.
*/
static jlong
readCEN(jzfile *zip, jint knownTotal)
{
/* Following are unsigned 32-bit */
jlong endpos, end64pos, cenpos, cenlen, cenoff;
/* Following are unsigned 16-bit */
jint total, tablelen, i, j;
unsigned char *cenbuf = NULL;
unsigned char *cenend;
unsigned char *cp;
#ifdef USE_MMAP
static jlong pagesize;
jlong offset;
#endif
unsigned char endbuf[ENDHDR];
jint endhdrlen = ENDHDR;
jzcell *entries;
jint *table;
/* Clear previous zip error */
zip->msg = NULL;
/* Get position of END header */
if ((endpos = findEND(zip, endbuf)) == -1)
return -1; /* no END header or system error */
if (endpos == 0) return 0; /* only END header present */
freeCEN(zip);
/* Get position and length of central directory */
cenlen = ENDSIZ(endbuf);
cenoff = ENDOFF(endbuf);
total = ENDTOT(endbuf);
if (cenlen == ZIP64_MAGICVAL || cenoff == ZIP64_MAGICVAL ||
total == ZIP64_MAGICCOUNT) {
unsigned char end64buf[ZIP64_ENDHDR];
if ((end64pos = findEND64(zip, end64buf, endpos)) != -1) {
cenlen = ZIP64_ENDSIZ(end64buf);
cenoff = ZIP64_ENDOFF(end64buf);
total = (jint)ZIP64_ENDTOT(end64buf);
endpos = end64pos;
endhdrlen = ZIP64_ENDHDR;
}
}
if (cenlen > endpos)
ZIP_FORMAT_ERROR("invalid END header (bad central directory size)");
cenpos = endpos - cenlen;
/* Get position of first local file (LOC) header, taking into
* account that there may be a stub prefixed to the zip file. */
zip->locpos = cenpos - cenoff;
if (zip->locpos < 0)
ZIP_FORMAT_ERROR("invalid END header (bad central directory offset)");
#ifdef USE_MMAP
if (zip->usemmap) {
/* On Solaris & Linux prior to JDK 6, we used to mmap the whole jar file to
* read the jar file contents. However, this greatly increased the perceived
* footprint numbers because the mmap'ed pages were adding into the totals shown
* by 'ps' and 'top'. We switched to mmaping only the central directory of jar
* file while calling 'read' to read the rest of jar file. Here are a list of
* reasons apart from above of why we are doing so:
* 1. Greatly reduces mmap overhead after startup complete;
* 2. Avoids dual path code maintainance;
* 3. Greatly reduces risk of address space (not virtual memory) exhaustion.
*/
if (pagesize == 0) {
pagesize = (jlong)sysconf(_SC_PAGESIZE);
if (pagesize == 0) goto Catch;
}
if (cenpos > pagesize) {
offset = cenpos & ~(pagesize - 1);
} else {
offset = 0;
}
/* When we are not calling recursively, knownTotal is -1. */
if (knownTotal == -1) {
void* mappedAddr;
/* Mmap the CEN and END part only. We have to figure
out the page size in order to make offset to be multiples of
page size.
*/
zip->mlen = cenpos - offset + cenlen + endhdrlen;
zip->offset = offset;
mappedAddr = mmap64(0, zip->mlen, PROT_READ, MAP_SHARED, zip->zfd, (off64_t) offset);
zip->maddr = (mappedAddr == (void*) MAP_FAILED) ? NULL :
(unsigned char*)mappedAddr;
if (zip->maddr == NULL) {
jio_fprintf(stderr, "mmap failed for CEN and END part of zip file\n");
goto Catch;
}
}
cenbuf = zip->maddr + cenpos - offset;
} else
#endif
{
if ((cenbuf = malloc((size_t) cenlen)) == NULL ||
(readFullyAt(zip->zfd, cenbuf, cenlen, cenpos) == -1))
goto Catch;
}
cenend = cenbuf + cenlen;
/* Initialize zip file data structures based on the total number
* of central directory entries as stored in ENDTOT. Since this
* is a 2-byte field, but we (and other zip implementations)
* support approx. 2**31 entries, we do not trust ENDTOT, but
* treat it only as a strong hint. When we call ourselves
* recursively, knownTotal will have the "true" value.
*
* Keep this path alive even with the Zip64 END support added, just
* for zip files that have more than 0xffff entries but don't have
* the Zip64 enabled.
*/
total = (knownTotal != -1) ? knownTotal : total;
entries = zip->entries = calloc(total, sizeof(entries[0]));
tablelen = zip->tablelen = ((total/2) | 1); // Odd -> fewer collisions
table = zip->table = malloc(tablelen * sizeof(table[0]));
if (entries == NULL || table == NULL) goto Catch;
for (j = 0; j < tablelen; j++)
table[j] = ZIP_ENDCHAIN;
/* Iterate through the entries in the central directory */
for (i = 0, cp = cenbuf; cp <= cenend - CENHDR; i++, cp += CENSIZE(cp)) {
/* Following are unsigned 16-bit */
jint method, nlen;
unsigned int hsh;
if (i >= total) {
/* This will only happen if the zip file has an incorrect
* ENDTOT field, which usually means it contains more than
* 65535 entries. */
cenpos = readCEN(zip, countCENHeaders(cenbuf, cenend));
goto Finally;
}
method = CENHOW(cp);
nlen = CENNAM(cp);
if (GETSIG(cp) != CENSIG)
ZIP_FORMAT_ERROR("invalid CEN header (bad signature)");
if (CENFLG(cp) & 1)
ZIP_FORMAT_ERROR("invalid CEN header (encrypted entry)");
if (method != STORED && method != DEFLATED)
ZIP_FORMAT_ERROR("invalid CEN header (bad compression method)");
if (cp + CENHDR + nlen > cenend)
ZIP_FORMAT_ERROR("invalid CEN header (bad header size)");
/* if the entry is metadata add it to our metadata names */
if (isMetaName((char *)cp+CENHDR, nlen))
if (addMetaName(zip, (char *)cp+CENHDR, nlen) != 0)
goto Catch;
/* Record the CEN offset and the name hash in our hash cell. */
entries[i].cenpos = cenpos + (cp - cenbuf);
entries[i].hash = hashN((char *)cp+CENHDR, nlen);
/* Add the entry to the hash table */
hsh = entries[i].hash % tablelen;
entries[i].next = table[hsh];
table[hsh] = i;
}
if (cp != cenend)
ZIP_FORMAT_ERROR("invalid CEN header (bad header size)");
zip->total = i;
goto Finally;
Catch:
freeCEN(zip);
cenpos = -1;
Finally:
#ifdef USE_MMAP
if (!zip->usemmap)
#endif
free(cenbuf);
return cenpos;
}
static int
find_file(int fd, zentry *entry, const char *file_name)
{
int bytes;
int res;
int entry_size;
int read_size;
int base_offset;
Byte *p;
Byte *bp;
Byte *buffer;
Byte locbuf[LOCHDR];
if ((buffer = (Byte*)malloc(BUFSIZE)) == NULL) {
return(-1);
}
p = buffer;
bp = buffer;
/*
* Read the END Header, which is the starting point for ZIP files.
* (Clearly designed to make writing a zip file easier than reading
* one. Now isn't that precious...)
*/
if ((base_offset = find_end(fd, bp)) == -1) {
free(buffer);
return (-1);
}
/*
* There is a historical, but undocumented, ability to allow for
* additional "stuff" to be prepended to the zip/jar file. It seems
* that this has been used to prepend an actual java launcher
* executable to the jar on Windows. Although this is just another
* form of statically linking a small piece of the JVM to the
* application, we choose to continue to support it. Note that no
* guarantees have been made (or should be made) to the customer that
* this will continue to work.
*
* Therefore, calculate the base offset of the zip file (within the
* expanded file) by assuming that the central directory is followed
* immediately by the end record.
*/
base_offset = base_offset - ENDSIZ(p) - ENDOFF(p);
/*
* The END Header indicates the start of the Central Directory
* Headers. Remember that the desired Central Directory Header (CEN)
* will almost always be the second one and the first one is a small
* directory entry ("META-INF/"). Keep the code optimized for
* that case.
*
* Begin by seeking to the beginning of the Central Directory and
* reading in the first buffer full of bits.
*/
if (lseek(fd, base_offset + ENDOFF(p), SEEK_SET) < (off_t)0) {
free(buffer);
return (-1);
}
if ((bytes = read(fd, bp, MINREAD)) < 0) {
free(buffer);
return (-1);
}
/*
* Loop through the Central Directory Headers. Note that a valid zip/jar
* must have an ENDHDR (with ENDSIG) after the Central Directory.
*/
while (GETSIG(p) == CENSIG) {
/*
* If a complete header isn't in the buffer, shift the contents
* of the buffer down and refill the buffer. Note that the check
* for "bytes < CENHDR" must be made before the test for the entire
* size of the header, because if bytes is less than CENHDR, the
* actual size of the header can't be determined. The addition of
* SIGSIZ guarantees that the next signature is also in the buffer
* for proper loop termination.
*/
if (bytes < CENHDR) {
p = memmove(bp, p, bytes);
if ((res = read(fd, bp + bytes, MINREAD)) <= 0) {
free(buffer);
return (-1);
}
bytes += res;
}
entry_size = CENHDR + CENNAM(p) + CENEXT(p) + CENCOM(p);
if (bytes < entry_size + SIGSIZ) {
if (p != bp)
p = memmove(bp, p, bytes);
read_size = entry_size - bytes + SIGSIZ;
read_size = (read_size < MINREAD) ? MINREAD : read_size;
if ((res = read(fd, bp + bytes, read_size)) <= 0) {
free(buffer);
return (-1);
}
bytes += res;
}
/*
* Check if the name is the droid we are looking for; the jar file
* manifest. If so, build the entry record from the data found in
* the header located and return success.
*/
if (CENNAM(p) == strlen(file_name) &&
memcmp((p + CENHDR), file_name, strlen(file_name)) == 0) {
if (lseek(fd, base_offset + CENOFF(p), SEEK_SET) < (off_t)0) {
free(buffer);
return (-1);
}
if (read(fd, locbuf, LOCHDR) < 0) {
free(buffer);
return (-1);
}
if (GETSIG(locbuf) != LOCSIG) {
free(buffer);
return (-1);
}
entry->isize = CENLEN(p);
entry->csize = CENSIZ(p);
entry->offset = base_offset + CENOFF(p) + LOCHDR +
LOCNAM(locbuf) + LOCEXT(locbuf);
entry->how = CENHOW(p);
free(buffer);
return (0);
}
/*
* Point to the next entry and decrement the count of valid remaining
* bytes.
*/
bytes -= entry_size;
p += entry_size;
}
free(buffer);
return (-1); /* Fell off the end the loop without a Manifest */
}
/**
* Writes all entries except ".class" to the data_file_handle,
* writes corresponding central directory records and the end of central
* directory record to the directory_file_handle.
* Treats .ZIP file format as documented in
* ftp://ftp.uu.net/pub/archiving/zip/doc/appnote-970311-iz.zip.
* Assumes that the .ZIP file doesn't span across multiple disks.
* Assumes that raw_current_entry()->nextCenOffset contains the offset
* of the first entry of the central directory (as set in the constructor).
* Returns true if completes successfully, false otherwise.
*/
bool
JarFileParser::copy_non_class_entries_to(OsFile_Handle data_file_handle,
OsFile_Handle directory_file_handle
JVM_TRAPS) {
UsingFastOops fast_oops;
BufferedFile::Fast jar_buffer = buffered_file();
const char class_suffix[] = {'.','c','l','a','s','s','\0'};
juint locOffset = raw_current_entry()->locOffset;
const juint buffer_size = MAX_ENTRY_NAME;
DECLARE_STATIC_BUFFER(unsigned char, buffer, buffer_size);
unsigned int name_length = 0;
juint loc_header_offset = 0;
juint cen_header_offset = 0;
size_t bytes_to_copy = 0;
unsigned int written_entry_count = 0;
unsigned int read_entry_count = 0;
unsigned int total_entry_count = raw_current_entry()->totalEntryCount;
// No OsFile_ routine to get the current position,
// so keep this information by ourselves.
juint data_file_position = 0;
juint directory_file_position = 0;
GUARANTEE(buffer_size >= LOCHDRSIZ &&
buffer_size >= EXTHDRSIZ &&
buffer_size >= ENDHDRSIZ &&
buffer_size >= MAX_ENTRY_NAME, "Buffer is too small");
if ((OsFile_seek(data_file_handle, 0L, SEEK_SET) < 0)
|| (OsFile_seek(directory_file_handle, 0L, SEEK_SET) < 0)) {
return false;
}
for (read_entry_count = 0; read_entry_count < total_entry_count;
read_entry_count++) {
// Find the next entry in the JAR.
bool found = find_entry(NULL JVM_MUST_SUCCEED);
if (!found) {
return false;
}
cen_header_offset = raw_current_entry()->nextCenOffset;
// If find_entry succeeded, centralHeader contains the central directory
// header for the found entry.
unsigned char *cenp = (unsigned char *)raw_current_entry()->centralHeader;
name_length = CENNAM(cenp);
if (name_length >= MAX_ENTRY_NAME) {
Throw::error(jarfile_error JVM_THROW_0);
} else {
jar_buffer().get_bytes(buffer, name_length);
if (!JarFileParser::match(class_suffix, (char*)buffer, name_length)) {
loc_header_offset = locOffset + CENOFF(cenp);
// Update the relative offset of local header
// in the central directory entry.
// Use little-endian order according to the .ZIP format.
Bytes::put_Java_u4(cenp + CENOFF_OFFSET,
Bytes::swap_u4(data_file_position));
// Write the central directory entry to the directory file.
if (OsFile_write(directory_file_handle,
cenp, 1, CENHDRSIZ) != CENHDRSIZ) {
return false;
}
directory_file_position += CENHDRSIZ;
// Write the file name to the direcory file.
if (OsFile_write(directory_file_handle,
buffer, 1, name_length) != name_length) {
return false;
}
directory_file_position += name_length;
// Copy the extra field and file comment to the directory file.
bytes_to_copy = CENEXT(cenp) + CENCOM(cenp);
if (block_copy(&jar_buffer, directory_file_handle,
bytes_to_copy) != bytes_to_copy) {
return false;
}
directory_file_position += bytes_to_copy;
// Copy the local file header to the data file.
if ((jar_buffer().seek(loc_header_offset, SEEK_SET) < 0)
|| (jar_buffer().get_bytes(buffer, LOCHDRSIZ) != LOCHDRSIZ)
|| (OsFile_write(data_file_handle,
buffer, 1, LOCHDRSIZ) != LOCHDRSIZ)) {
return false;
}
data_file_position += LOCHDRSIZ;
{
unsigned char *locp = (unsigned char *)buffer;
// Copy the file name, extra field and the compressed file data
// to the data file.
bytes_to_copy = LOCNAM(locp) + LOCEXT(locp) + CENSIZ(cenp);
if (block_copy(&jar_buffer, data_file_handle,
bytes_to_copy) != bytes_to_copy) {
return false;
}
data_file_position += bytes_to_copy;
// Check if the data descriptor exists.
if ((LOCFLG(locp) & 8) == 8) {
// Copy the data descriptor to the data file.
if (jar_buffer().get_bytes(buffer, EXTHDRSIZ) != EXTHDRSIZ) {
return false;
}
// The data descriptor may or may not start with the signature
// depending on .ZIP file format revision used.
if (GETSIG(buffer) == EXTSIG) {
// According to the Info-ZIP Application Note 970311,
// the data descriptor starts with the signature.
if (OsFile_write(data_file_handle,
buffer, 1, EXTHDRSIZ) != EXTHDRSIZ) {
return false;
}
data_file_position += EXTHDRSIZ;
} else {
// According to the .ZIP format specification version 6.1.0,
// the data descriptor doesn't start with the signature.
if (OsFile_write(data_file_handle,
buffer, 1, EXTHDRSIZ - 4) != EXTHDRSIZ - 4) {
return false;
}
data_file_position += EXTHDRSIZ - 4;
}
}
}
written_entry_count++;
}
}
cen_header_offset += CENHDRSIZ + name_length + CENEXT(cenp) + CENCOM(cenp);
raw_current_entry()->nextCenOffset = cen_header_offset;
}
// Now that all central directory entries are processed,
// cen_header_offset points to the end of the central directory.
if (jar_buffer().seek(cen_header_offset, SEEK_SET) < 0) {
return false;
}
if (jar_buffer().get_bytes(buffer, ENDHDRSIZ) != ENDHDRSIZ) {
return false;
}
{
unsigned char *endp = (unsigned char *)buffer;
if (GETSIG(endp) != ENDSIG) {
return false;
}
// Update the record to match the new number of entries.
// Use little-endian order according to the .ZIP format.
Bytes::put_Java_u2(endp + ENDSUB_OFFSET,
Bytes::swap_u2(written_entry_count));
Bytes::put_Java_u2(endp + ENDTOT_OFFSET,
Bytes::swap_u2(written_entry_count));
// The size of the central directory is exactly
// the number of bytes written to the directory_file.
Bytes::put_Java_u4(endp + ENDSIZ_OFFSET,
Bytes::swap_u4(directory_file_position));
// The offset of the central directory is exactly
// the number of bytes written to the data_file.
Bytes::put_Java_u4(endp + ENDOFF_OFFSET,
Bytes::swap_u4(data_file_position));
if (OsFile_write(directory_file_handle, endp, 1, ENDHDRSIZ) != ENDHDRSIZ) {
return false;
}
if (block_copy(&jar_buffer,
directory_file_handle, ENDCOM(endp)) != (size_t)ENDCOM(endp)) {
return false;
}
}
return true;
}
int
JarFileParser::filtered_do_next_entries(JvmNameFilterProc entry_filter_proc,
JvmDoJarEntryProc do_jar_entry_proc,
void* caller_data,
int entry_id, int max_size
JVM_TRAPS) {
GUARANTEE(entry_id >= 0 && max_size > 0, "Sanity");
DECLARE_STATIC_BUFFER(char, entry_name, MAX_ENTRY_NAME);
unsigned int name_length = 0;
int total_size = 0;
if (max_size <= 0) {
max_size = max_jint;
}
if (entry_id > 0) {
raw_current_entry()->nextCenOffset = entry_id;
}
// NOTE: max_entries can be -1 that indicates no limitation on the number of
// entries processed.
for (total_size = 0; total_size < max_size;) {
bool found = find_entry(NULL JVM_MUST_SUCCEED);
if (!found) {
break;
}
// If find_entry succeeded, centralHeader contains the central directory
// header for the found entry.
unsigned char *cenp = (unsigned char *)raw_current_entry()->centralHeader;
name_length = CENNAM(cenp);
if (name_length >= MAX_ENTRY_NAME) {
return -1;
}
// Save the next offset as entry_filter_proc may move raw_current_entry()
juint nextCenOffset = raw_current_entry()->nextCenOffset +
CENHDRSIZ + name_length + CENEXT(cenp) + CENCOM(cenp);
{
UsingFastOops fast_oops;
BufferedFile::Fast bf = buffered_file();
if (bf().get_bytes((address)entry_name, name_length) != name_length) {
return -1;
}
}
entry_name[name_length] = '\0';
if (((entry_filter_proc == NULL) ||
(entry_filter_proc(entry_name, caller_data) == KNI_TRUE)) &&
(do_jar_entry_proc != NULL)) {
UsingFastOops fast_oops;
Buffer::Fast buffer = load_entry(JVM_SINGLE_ARG_CHECK_0);
if (buffer.is_null()) {
return -1;
}
if (do_jar_entry_proc((char*)entry_name, buffer().data(),
buffer().length(), caller_data) == KNI_FALSE) {
return 0;
}
}
total_size += raw_current_entry()->length;
if (CURRENT_HAS_PENDING_EXCEPTION) {
// if entry_filter_proc returned NULL, check for exception
return -1;
}
raw_current_entry()->nextCenOffset = nextCenOffset;
}
// If we reached the end of JAR return 0.
// Otherwise return nextCenOffset, it is used as a JAR entry id.
return (total_size < max_size) ? 0 : raw_current_entry()->nextCenOffset;
}
/*
* Locate the manifest file with the zip/jar file.
*
* fd: File descriptor of the jar file.
* entry: To be populated with the information necessary to perform
* the inflation (the compressed and uncompressed sizes and
* the offset in the file where the compressed data is located).
*
* Returns zero upon success. Returns a negative value upon failure.
*
* The buffer for reading the Central Directory if the zip/jar file needs
* to be large enough to accommodate the largest possible single record
* and the signature of the next record which is:
*
* 3*2**16 + CENHDR + SIGSIZ
*
* Each of the three variable sized fields (name, comment and extension)
* has a maximum possible size of 64k.
*
* Typically, only a small bit of this buffer is used with bytes shuffled
* down to the beginning of the buffer. It is one thing to allocate such
* a large buffer and another thing to actually start faulting it in.
*
* In most cases, all that needs to be read are the first two entries in
* a typical jar file (META-INF and META-INF/MANIFEST.MF). Keep this factoid
* in mind when optimizing this code.
*/
static int
find_file(int fd, zentry *entry, const char *file_name)
{
int bytes;
int res;
int entry_size;
int read_size;
jlong base_offset;
Byte *p;
Byte *bp;
Byte *buffer;
Byte locbuf[LOCHDR];
if ((buffer = (Byte*)malloc(BUFSIZE)) == NULL) {
return(-1);
}
bp = buffer;
base_offset = compute_cen(fd, bp);
if (base_offset == -1) {
free(buffer);
return -1;
}
if ((bytes = read(fd, bp, MINREAD)) < 0) {
free(buffer);
return (-1);
}
p = bp;
/*
* Loop through the Central Directory Headers. Note that a valid zip/jar
* must have an ENDHDR (with ENDSIG) after the Central Directory.
*/
while (GETSIG(p) == CENSIG) {
/*
* If a complete header isn't in the buffer, shift the contents
* of the buffer down and refill the buffer. Note that the check
* for "bytes < CENHDR" must be made before the test for the entire
* size of the header, because if bytes is less than CENHDR, the
* actual size of the header can't be determined. The addition of
* SIGSIZ guarantees that the next signature is also in the buffer
* for proper loop termination.
*/
if (bytes < CENHDR) {
p = memmove(bp, p, bytes);
if ((res = read(fd, bp + bytes, MINREAD)) <= 0) {
free(buffer);
return (-1);
}
bytes += res;
}
entry_size = CENHDR + CENNAM(p) + CENEXT(p) + CENCOM(p);
if (bytes < entry_size + SIGSIZ) {
if (p != bp)
p = memmove(bp, p, bytes);
read_size = entry_size - bytes + SIGSIZ;
read_size = (read_size < MINREAD) ? MINREAD : read_size;
if ((res = read(fd, bp + bytes, read_size)) <= 0) {
free(buffer);
return (-1);
}
bytes += res;
}
/*
* Check if the name is the droid we are looking for; the jar file
* manifest. If so, build the entry record from the data found in
* the header located and return success.
*/
if ((size_t)CENNAM(p) == JLI_StrLen(file_name) &&
memcmp((p + CENHDR), file_name, JLI_StrLen(file_name)) == 0) {
if (JLI_Lseek(fd, base_offset + CENOFF(p), SEEK_SET) < (jlong)0) {
free(buffer);
return (-1);
}
if (read(fd, locbuf, LOCHDR) < 0) {
free(buffer);
return (-1);
}
if (GETSIG(locbuf) != LOCSIG) {
free(buffer);
return (-1);
}
entry->isize = CENLEN(p);
entry->csize = CENSIZ(p);
entry->offset = base_offset + CENOFF(p) + LOCHDR +
LOCNAM(locbuf) + LOCEXT(locbuf);
entry->how = CENHOW(p);
free(buffer);
return (0);
}
/*
* Point to the next entry and decrement the count of valid remaining
* bytes.
*/
bytes -= entry_size;
p += entry_size;
}
free(buffer);
return (-1); /* Fell off the end the loop without a Manifest */
}
