2
* xzlib.c: front end for the transparent suport of lzma compression
3
* at the I/O layer, based on an example file from lzma project
5
* See Copyright for the status of this software.
7
* Anders F Bjorklund <afb@users.sourceforge.net>
19
#ifdef HAVE_SYS_TYPES_H
20
#include <sys/types.h>
22
#ifdef HAVE_SYS_STAT_H
40
#include <libxml/xmlmemory.h>
42
/* values for xz_state how */
43
#define LOOK 0 /* look for a gzip/lzma header */
44
#define COPY 1 /* copy input directly */
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#define GZIP 2 /* decompress a gzip stream */
46
#define LZMA 3 /* decompress a lzma stream */
48
/* internal lzma file state data structure */
50
int mode; /* see lzma modes above */
51
int fd; /* file descriptor */
52
char *path; /* path or fd for error messages */
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uint64_t pos; /* current position in uncompressed data */
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unsigned int size; /* buffer size, zero if not allocated yet */
55
unsigned int want; /* requested buffer size, default is BUFSIZ */
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unsigned char *in; /* input buffer */
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unsigned char *out; /* output buffer (double-sized when reading) */
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unsigned char *next; /* next output data to deliver or write */
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unsigned int have; /* amount of output data unused at next */
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int eof; /* true if end of input file reached */
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uint64_t start; /* where the lzma data started, for rewinding */
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uint64_t raw; /* where the raw data started, for seeking */
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int how; /* 0: get header, 1: copy, 2: decompress */
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int direct; /* true if last read direct, false if lzma */
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uint64_t skip; /* amount to skip (already rewound if backwards) */
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int seek; /* true if seek request pending */
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/* error information */
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int err; /* error code */
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char *msg; /* error message */
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int init; /* is the iniflate stream initialized */
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lzma_stream strm; /* stream structure in-place (not a pointer) */
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char padding1[32]; /* padding allowing to cope with possible
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extensions of above structure without
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too much side effect */
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/* zlib inflate or deflate stream */
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z_stream zstrm; /* stream structure in-place (not a pointer) */
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char padding2[32]; /* padding allowing to cope with possible
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extensions of above structure without
83
too much side effect */
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} xz_state, *xz_statep;
87
xz_error(xz_statep state, int err, const char *msg)
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/* free previously allocated message and clear */
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if (state->msg != NULL) {
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if (state->err != LZMA_MEM_ERROR)
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/* set error code, and if no message, then done */
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/* for an out of memory error, save as static string */
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if (err == LZMA_MEM_ERROR) {
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state->msg = (char *) msg;
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/* construct error message with path */
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xmlMalloc(strlen(state->path) + strlen(msg) + 3)) == NULL) {
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state->err = LZMA_MEM_ERROR;
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state->msg = (char *) "out of memory";
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strcpy(state->msg, state->path);
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strcat(state->msg, ": ");
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strcat(state->msg, msg);
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xz_reset(xz_statep state)
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state->have = 0; /* no output data available */
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state->eof = 0; /* not at end of file */
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state->how = LOOK; /* look for gzip header */
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state->direct = 1; /* default for empty file */
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state->seek = 0; /* no seek request pending */
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xz_error(state, LZMA_OK, NULL); /* clear error */
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state->pos = 0; /* no uncompressed data yet */
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state->strm.avail_in = 0; /* no input data yet */
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state->zstrm.avail_in = 0; /* no input data yet */
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xz_open(const char *path, int fd, const char *mode ATTRIBUTE_UNUSED)
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/* allocate xzFile structure to return */
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state = xmlMalloc(sizeof(xz_state));
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state->size = 0; /* no buffers allocated yet */
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state->want = BUFSIZ; /* requested buffer size */
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state->msg = NULL; /* no error message yet */
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state->init = 0; /* initialization of zlib data */
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/* save the path name for error messages */
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state->path = xmlMalloc(strlen(path) + 1);
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if (state->path == NULL) {
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strcpy(state->path, path);
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/* open the file with the appropriate mode (or just use fd) */
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state->fd = fd != -1 ? fd : open(path,
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if (state->fd == -1) {
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xmlFree(state->path);
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/* save the current position for rewinding (only if reading) */
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state->start = lseek(state->fd, 0, SEEK_CUR);
175
if (state->start == (uint64_t) - 1)
178
/* initialize stream */
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return (xzFile) state;
186
__libxml2_xzopen(const char *path, const char *mode)
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return xz_open(path, -1, mode);
192
__libxml2_xzdopen(int fd, const char *mode)
194
char *path; /* identifier for error messages */
197
if (fd == -1 || (path = xmlMalloc(7 + 3 * sizeof(int))) == NULL)
199
sprintf(path, "<fd:%d>", fd); /* for debugging */
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xz = xz_open(path, fd, mode);
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xz_load(xz_statep state, unsigned char *buf, unsigned int len,
213
ret = read(state->fd, buf + *have, len - *have);
217
} while (*have < len);
219
xz_error(state, -1, strerror(errno));
228
xz_avail(xz_statep state)
230
lzma_stream *strm = &(state->strm);
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if (state->err != LZMA_OK)
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if (state->eof == 0) {
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/* avail_in is size_t, which is not necessary sizeof(unsigned) */
236
unsigned tmp = strm->avail_in;
238
if (xz_load(state, state->in, state->size, &tmp) == -1) {
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strm->avail_in = tmp;
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strm->avail_in = tmp;
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strm->next_in = state->in;
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is_format_xz(xz_statep state)
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lzma_stream *strm = &(state->strm);
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return strm->avail_in >= 6 && memcmp(state->in, "\3757zXZ", 6) == 0;
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is_format_lzma(xz_statep state)
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lzma_stream *strm = &(state->strm);
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lzma_options_lzma *opt;
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uint64_t uncompressed_size;
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if (strm->avail_in < 13)
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filter.id = LZMA_FILTER_LZMA1;
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if (lzma_properties_decode(&filter, NULL, state->in, 5) != LZMA_OK)
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opt = filter.options;
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dict_size = opt->dict_size;
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free(opt); /* we can't use xmlFree on a string returned by zlib */
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/* A hack to ditch tons of false positives: We allow only dictionary
279
* sizes that are 2^n or 2^n + 2^(n-1) or UINT32_MAX. LZMA_Alone
280
* created only files with 2^n, but accepts any dictionary size.
281
* If someone complains, this will be reconsidered.
283
if (dict_size != UINT32_MAX) {
284
uint32_t d = dict_size - 1;
292
if (d != dict_size || dict_size == 0)
296
/* Another hack to ditch false positives: Assume that if the
297
* uncompressed size is known, it must be less than 256 GiB.
298
* Again, if someone complains, this will be reconsidered.
300
uncompressed_size = 0;
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for (i = 0; i < 8; ++i)
302
uncompressed_size |= (uint64_t) (state->in[5 + i]) << (i * 8);
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if (uncompressed_size != UINT64_MAX
305
&& uncompressed_size > (UINT64_C(1) << 38))
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/* Get next byte from input, or -1 if end or error. */
314
#define NEXT() ((strm->avail_in == 0 && xz_avail(state) == -1) ? -1 : \
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(strm->avail_in == 0 ? -1 : \
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(strm->avail_in--, *(strm->next_in)++)))
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/* Get a four-byte little-endian integer and return 0 on success and the value
319
in *ret. Otherwise -1 is returned and *ret is not modified. */
321
gz_next4(xz_statep state, unsigned long *ret)
325
z_streamp strm = &(state->zstrm);
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val += (unsigned) NEXT() << 8;
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val += (unsigned long) NEXT() << 16;
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val += (unsigned long) ch << 24;
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xz_head(xz_statep state)
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lzma_stream *strm = &(state->strm);
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lzma_stream init = LZMA_STREAM_INIT;
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/* allocate read buffers and inflate memory */
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if (state->size == 0) {
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/* allocate buffers */
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state->in = xmlMalloc(state->want);
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state->out = xmlMalloc(state->want << 1);
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if (state->in == NULL || state->out == NULL) {
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if (state->out != NULL)
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if (state->in != NULL)
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xz_error(state, LZMA_MEM_ERROR, "out of memory");
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state->size = state->want;
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/* allocate decoder memory */
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state->strm.avail_in = 0;
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state->strm.next_in = NULL;
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if (lzma_auto_decoder(&state->strm, UINT64_MAX, 0) != LZMA_OK) {
370
xz_error(state, LZMA_MEM_ERROR, "out of memory");
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/* allocate inflate memory */
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state->zstrm.zalloc = Z_NULL;
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state->zstrm.zfree = Z_NULL;
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state->zstrm.opaque = Z_NULL;
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state->zstrm.avail_in = 0;
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state->zstrm.next_in = Z_NULL;
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if (state->init == 0) {
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if (inflateInit2(&(state->zstrm), -15) != Z_OK) {/* raw inflate */
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xz_error(state, LZMA_MEM_ERROR, "out of memory");
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/* get some data in the input buffer */
394
if (strm->avail_in == 0) {
395
if (xz_avail(state) == -1)
397
if (strm->avail_in == 0)
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/* look for the xz magic header bytes */
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if (is_format_xz(state) || is_format_lzma(state)) {
408
/* look for the gzip magic header bytes 31 and 139 */
409
if (strm->next_in[0] == 31) {
412
if (strm->avail_in == 0 && xz_avail(state) == -1)
414
if (strm->avail_in && strm->next_in[0] == 139) {
415
/* we have a gzip header, woo hoo! */
419
/* skip rest of header */
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if (NEXT() != 8) { /* compression method */
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xz_error(state, LZMA_DATA_ERROR,
422
"unknown compression method");
426
if (flags & 0xe0) { /* reserved flag bits */
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xz_error(state, LZMA_DATA_ERROR,
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"unknown header flags set");
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NEXT(); /* modification time */
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NEXT(); /* extra flags */
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NEXT(); /* operating system */
437
if (flags & 4) { /* extra field */
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len = (unsigned) NEXT();
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len += (unsigned) NEXT() << 8;
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if (flags & 8) /* file name */
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if (flags & 16) /* comment */
448
if (flags & 2) { /* header crc */
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/* an unexpected end of file is not checked for here -- it will be
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* noticed on the first request for uncompressed data */
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/* set up for decompression */
456
inflateReset(&state->zstrm);
457
state->zstrm.adler = crc32(0L, Z_NULL, 0);
462
/* not a gzip file -- save first byte (31) and fall to raw i/o */
469
/* doing raw i/o, save start of raw data for seeking, copy any leftover
470
* input to output -- this assumes that the output buffer is larger than
471
* the input buffer, which also assures space for gzungetc() */
472
state->raw = state->pos;
473
state->next = state->out;
474
if (strm->avail_in) {
475
memcpy(state->next + state->have, strm->next_in, strm->avail_in);
476
state->have += strm->avail_in;
485
xz_decomp(xz_statep state)
489
unsigned long crc, len;
490
lzma_stream *strm = &(state->strm);
492
lzma_action action = LZMA_RUN;
494
/* fill output buffer up to end of deflate stream */
495
had = strm->avail_out;
497
/* get more input for inflate() */
498
if (strm->avail_in == 0 && xz_avail(state) == -1)
500
if (strm->avail_in == 0) {
501
xz_error(state, LZMA_DATA_ERROR, "unexpected end of file");
505
action = LZMA_FINISH;
507
/* decompress and handle errors */
509
if (state->how == GZIP) {
510
state->zstrm.avail_in = (uInt) state->strm.avail_in;
511
state->zstrm.next_in = (Bytef *) state->strm.next_in;
512
state->zstrm.avail_out = (uInt) state->strm.avail_out;
513
state->zstrm.next_out = (Bytef *) state->strm.next_out;
514
ret = inflate(&state->zstrm, Z_NO_FLUSH);
515
if (ret == Z_STREAM_ERROR || ret == Z_NEED_DICT) {
516
xz_error(state, Z_STREAM_ERROR,
517
"internal error: inflate stream corrupt");
520
if (ret == Z_MEM_ERROR)
521
ret = LZMA_MEM_ERROR;
522
if (ret == Z_DATA_ERROR)
523
ret = LZMA_DATA_ERROR;
524
if (ret == Z_STREAM_END)
525
ret = LZMA_STREAM_END;
526
state->strm.avail_in = state->zstrm.avail_in;
527
state->strm.next_in = state->zstrm.next_in;
528
state->strm.avail_out = state->zstrm.avail_out;
529
state->strm.next_out = state->zstrm.next_out;
530
} else /* state->how == LZMA */
532
ret = lzma_code(strm, action);
533
if (ret == LZMA_MEM_ERROR) {
534
xz_error(state, LZMA_MEM_ERROR, "out of memory");
537
if (ret == LZMA_DATA_ERROR) {
538
xz_error(state, LZMA_DATA_ERROR, "compressed data error");
541
} while (strm->avail_out && ret != LZMA_STREAM_END);
543
/* update available output and crc check value */
544
state->have = had - strm->avail_out;
545
state->next = strm->next_out - state->have;
548
crc32(state->zstrm.adler, state->next, state->have);
551
if (ret == LZMA_STREAM_END) {
553
if (state->how == GZIP) {
554
if (gz_next4(state, &crc) == -1 || gz_next4(state, &len) == -1) {
555
xz_error(state, LZMA_DATA_ERROR, "unexpected end of file");
558
if (crc != state->zstrm.adler) {
559
xz_error(state, LZMA_DATA_ERROR, "incorrect data check");
562
if (len != (state->zstrm.total_out & 0xffffffffL)) {
563
xz_error(state, LZMA_DATA_ERROR, "incorrect length check");
566
state->strm.avail_in = 0;
567
state->strm.next_in = NULL;
568
state->strm.avail_out = 0;
569
state->strm.next_out = NULL;
572
if (strm->avail_in != 0 || !state->eof) {
573
xz_error(state, LZMA_DATA_ERROR, "trailing garbage");
576
state->how = LOOK; /* ready for next stream, once have is 0 (leave
577
* state->direct unchanged to remember how) */
580
/* good decompression */
585
xz_make(xz_statep state)
587
lzma_stream *strm = &(state->strm);
589
if (state->how == LOOK) { /* look for lzma / gzip header */
590
if (xz_head(state) == -1)
592
if (state->have) /* got some data from xz_head() */
595
if (state->how == COPY) { /* straight copy */
596
if (xz_load(state, state->out, state->size << 1, &(state->have)) ==
599
state->next = state->out;
600
} else if (state->how == LZMA || state->how == GZIP) { /* decompress */
601
strm->avail_out = state->size << 1;
602
strm->next_out = state->out;
603
if (xz_decomp(state) == -1)
610
xz_skip(xz_statep state, uint64_t len)
614
/* skip over len bytes or reach end-of-file, whichever comes first */
616
/* skip over whatever is in output buffer */
618
n = (uint64_t) state->have > len ?
619
(unsigned) len : state->have;
626
/* output buffer empty -- return if we're at the end of the input */
627
else if (state->eof && state->strm.avail_in == 0)
630
/* need more data to skip -- load up output buffer */
632
/* get more output, looking for header if required */
633
if (xz_make(state) == -1)
640
__libxml2_xzread(xzFile file, void *buf, unsigned len)
646
/* get internal structure */
649
state = (xz_statep) file;
650
strm = &(state->strm);
652
/* check that we're reading and that there's no error */
653
if (state->err != LZMA_OK)
656
/* since an int is returned, make sure len fits in one, otherwise return
657
* with an error (this avoids the flaw in the interface) */
659
xz_error(state, LZMA_BUF_ERROR,
660
"requested length does not fit in int");
664
/* if len is zero, avoid unnecessary operations */
668
/* process a skip request */
671
if (xz_skip(state, state->skip) == -1)
675
/* get len bytes to buf, or less than len if at the end */
678
/* first just try copying data from the output buffer */
680
n = state->have > len ? len : state->have;
681
memcpy(buf, state->next, n);
686
/* output buffer empty -- return if we're at the end of the input */
687
else if (state->eof && strm->avail_in == 0)
690
/* need output data -- for small len or new stream load up our output
692
else if (state->how == LOOK || len < (state->size << 1)) {
693
/* get more output, looking for header if required */
694
if (xz_make(state) == -1)
696
continue; /* no progress yet -- go back to memcpy() above */
697
/* the copy above assures that we will leave with space in the
698
* output buffer, allowing at least one gzungetc() to succeed */
701
/* large len -- read directly into user buffer */
702
else if (state->how == COPY) { /* read directly */
703
if (xz_load(state, buf, len, &n) == -1)
707
/* large len -- decompress directly into user buffer */
708
else { /* state->how == LZMA */
709
strm->avail_out = len;
710
strm->next_out = buf;
711
if (xz_decomp(state) == -1)
717
/* update progress */
719
buf = (char *) buf + n;
724
/* return number of bytes read into user buffer (will fit in int) */
729
__libxml2_xzclose(xzFile file)
734
/* get internal structure */
736
return LZMA_DATA_ERROR;
737
state = (xz_statep) file;
739
/* free memory and close file */
741
lzma_end(&(state->strm));
743
if (state->init == 1)
744
inflateEnd(&(state->zstrm));
750
xmlFree(state->path);
751
ret = close(state->fd);
753
return ret ? ret : LZMA_OK;
755
#endif /* HAVE_LZMA_H */
added
removed
.pc/0019-Fix-a-bug-loading-some-compressed-files.patch/xzlib.c
