summaryrefslogtreecommitdiffstats
path: root/src/zstd/zlibWrapper/gzread.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--src/zstd/zlibWrapper/gzread.c670
1 files changed, 670 insertions, 0 deletions
diff --git a/src/zstd/zlibWrapper/gzread.c b/src/zstd/zlibWrapper/gzread.c
new file mode 100644
index 00000000..88fc06c7
--- /dev/null
+++ b/src/zstd/zlibWrapper/gzread.c
@@ -0,0 +1,670 @@
+/* gzread.c contains minimal changes required to be compiled with zlibWrapper:
+ * - gz_statep was converted to union to work with -Wstrict-aliasing=1 */
+
+ /* gzread.c -- zlib functions for reading gzip files
+ * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013, 2016 Mark Adler
+ * For conditions of distribution and use, see http://www.zlib.net/zlib_license.html
+ */
+
+#include "gzguts.h"
+
+/* Local functions */
+local int gz_load OF((gz_statep, unsigned char *, unsigned, unsigned *));
+local int gz_avail OF((gz_statep));
+local int gz_look OF((gz_statep));
+local int gz_decomp OF((gz_statep));
+local int gz_fetch OF((gz_statep));
+local int gz_skip OF((gz_statep, z_off64_t));
+local z_size_t gz_read OF((gz_statep, voidp, z_size_t));
+
+/* Use read() to load a buffer -- return -1 on error, otherwise 0. Read from
+ state.state->fd, and update state.state->eof, state.state->err, and state.state->msg as appropriate.
+ This function needs to loop on read(), since read() is not guaranteed to
+ read the number of bytes requested, depending on the type of descriptor. */
+local int gz_load(state, buf, len, have)
+ gz_statep state;
+ unsigned char *buf;
+ unsigned len;
+ unsigned *have;
+{
+ ssize_t ret;
+ unsigned get, max = ((unsigned)-1 >> 2) + 1;
+
+ *have = 0;
+ do {
+ get = len - *have;
+ if (get > max)
+ get = max;
+ ret = read(state.state->fd, buf + *have, get);
+ if (ret <= 0)
+ break;
+ *have += (unsigned)ret;
+ } while (*have < len);
+ if (ret < 0) {
+ gz_error(state, Z_ERRNO, zstrerror());
+ return -1;
+ }
+ if (ret == 0)
+ state.state->eof = 1;
+ return 0;
+}
+
+/* Load up input buffer and set eof flag if last data loaded -- return -1 on
+ error, 0 otherwise. Note that the eof flag is set when the end of the input
+ file is reached, even though there may be unused data in the buffer. Once
+ that data has been used, no more attempts will be made to read the file.
+ If strm->avail_in != 0, then the current data is moved to the beginning of
+ the input buffer, and then the remainder of the buffer is loaded with the
+ available data from the input file. */
+local int gz_avail(state)
+ gz_statep state;
+{
+ unsigned got;
+ z_streamp strm = &(state.state->strm);
+
+ if (state.state->err != Z_OK && state.state->err != Z_BUF_ERROR)
+ return -1;
+ if (state.state->eof == 0) {
+ if (strm->avail_in) { /* copy what's there to the start */
+ unsigned char *p = state.state->in;
+ unsigned const char *q = strm->next_in;
+ unsigned n = strm->avail_in;
+ do {
+ *p++ = *q++;
+ } while (--n);
+ }
+ if (gz_load(state, state.state->in + strm->avail_in,
+ state.state->size - strm->avail_in, &got) == -1)
+ return -1;
+ strm->avail_in += got;
+ strm->next_in = state.state->in;
+ }
+ return 0;
+}
+
+/* Look for gzip header, set up for inflate or copy. state.state->x.have must be 0.
+ If this is the first time in, allocate required memory. state.state->how will be
+ left unchanged if there is no more input data available, will be set to COPY
+ if there is no gzip header and direct copying will be performed, or it will
+ be set to GZIP for decompression. If direct copying, then leftover input
+ data from the input buffer will be copied to the output buffer. In that
+ case, all further file reads will be directly to either the output buffer or
+ a user buffer. If decompressing, the inflate state will be initialized.
+ gz_look() will return 0 on success or -1 on failure. */
+local int gz_look(state)
+ gz_statep state;
+{
+ z_streamp strm = &(state.state->strm);
+
+ /* allocate read buffers and inflate memory */
+ if (state.state->size == 0) {
+ /* allocate buffers */
+ state.state->in = (unsigned char *)malloc(state.state->want);
+ state.state->out = (unsigned char *)malloc(state.state->want << 1);
+ if (state.state->in == NULL || state.state->out == NULL) {
+ free(state.state->out);
+ free(state.state->in);
+ gz_error(state, Z_MEM_ERROR, "out of memory");
+ return -1;
+ }
+ state.state->size = state.state->want;
+
+ /* allocate inflate memory */
+ state.state->strm.zalloc = Z_NULL;
+ state.state->strm.zfree = Z_NULL;
+ state.state->strm.opaque = Z_NULL;
+ state.state->strm.avail_in = 0;
+ state.state->strm.next_in = Z_NULL;
+ if (inflateInit2(&(state.state->strm), 15 + 16) != Z_OK) { /* gunzip */
+ free(state.state->out);
+ free(state.state->in);
+ state.state->size = 0;
+ gz_error(state, Z_MEM_ERROR, "out of memory");
+ return -1;
+ }
+ }
+
+ /* get at least the magic bytes in the input buffer */
+ if (strm->avail_in < 2) {
+ if (gz_avail(state) == -1)
+ return -1;
+ if (strm->avail_in == 0)
+ return 0;
+ }
+
+ /* look for gzip magic bytes -- if there, do gzip decoding (note: there is
+ a logical dilemma here when considering the case of a partially written
+ gzip file, to wit, if a single 31 byte is written, then we cannot tell
+ whether this is a single-byte file, or just a partially written gzip
+ file -- for here we assume that if a gzip file is being written, then
+ the header will be written in a single operation, so that reading a
+ single byte is sufficient indication that it is not a gzip file) */
+ if (strm->avail_in > 1 &&
+ ((strm->next_in[0] == 31 && strm->next_in[1] == 139) /* gz header */
+ || (strm->next_in[0] == 40 && strm->next_in[1] == 181))) { /* zstd header */
+ inflateReset(strm);
+ state.state->how = GZIP;
+ state.state->direct = 0;
+ return 0;
+ }
+
+ /* no gzip header -- if we were decoding gzip before, then this is trailing
+ garbage. Ignore the trailing garbage and finish. */
+ if (state.state->direct == 0) {
+ strm->avail_in = 0;
+ state.state->eof = 1;
+ state.state->x.have = 0;
+ return 0;
+ }
+
+ /* doing raw i/o, copy any leftover input to output -- this assumes that
+ the output buffer is larger than the input buffer, which also assures
+ space for gzungetc() */
+ state.state->x.next = state.state->out;
+ if (strm->avail_in) {
+ memcpy(state.state->x.next, strm->next_in, strm->avail_in);
+ state.state->x.have = strm->avail_in;
+ strm->avail_in = 0;
+ }
+ state.state->how = COPY;
+ state.state->direct = 1;
+ return 0;
+}
+
+/* Decompress from input to the provided next_out and avail_out in the state.
+ On return, state.state->x.have and state.state->x.next point to the just decompressed
+ data. If the gzip stream completes, state.state->how is reset to LOOK to look for
+ the next gzip stream or raw data, once state.state->x.have is depleted. Returns 0
+ on success, -1 on failure. */
+local int gz_decomp(state)
+ gz_statep state;
+{
+ int ret = Z_OK;
+ unsigned had;
+ z_streamp strm = &(state.state->strm);
+
+ /* fill output buffer up to end of deflate stream */
+ had = strm->avail_out;
+ do {
+ /* get more input for inflate() */
+ if (strm->avail_in == 0 && gz_avail(state) == -1)
+ return -1;
+ if (strm->avail_in == 0) {
+ gz_error(state, Z_BUF_ERROR, "unexpected end of file");
+ break;
+ }
+
+ /* decompress and handle errors */
+ ret = inflate(strm, Z_NO_FLUSH);
+ if (ret == Z_STREAM_ERROR || ret == Z_NEED_DICT) {
+ gz_error(state, Z_STREAM_ERROR,
+ "internal error: inflate stream corrupt");
+ return -1;
+ }
+ if (ret == Z_MEM_ERROR) {
+ gz_error(state, Z_MEM_ERROR, "out of memory");
+ return -1;
+ }
+ if (ret == Z_DATA_ERROR) { /* deflate stream invalid */
+ gz_error(state, Z_DATA_ERROR,
+ strm->msg == NULL ? "compressed data error" : strm->msg);
+ return -1;
+ }
+ } while (strm->avail_out && ret != Z_STREAM_END);
+
+ /* update available output */
+ state.state->x.have = had - strm->avail_out;
+ state.state->x.next = strm->next_out - state.state->x.have;
+
+ /* if the gzip stream completed successfully, look for another */
+ if (ret == Z_STREAM_END)
+ state.state->how = LOOK;
+
+ /* good decompression */
+ return 0;
+}
+
+/* Fetch data and put it in the output buffer. Assumes state.state->x.have is 0.
+ Data is either copied from the input file or decompressed from the input
+ file depending on state.state->how. If state.state->how is LOOK, then a gzip header is
+ looked for to determine whether to copy or decompress. Returns -1 on error,
+ otherwise 0. gz_fetch() will leave state.state->how as COPY or GZIP unless the
+ end of the input file has been reached and all data has been processed. */
+local int gz_fetch(state)
+ gz_statep state;
+{
+ z_streamp strm = &(state.state->strm);
+
+ do {
+ switch(state.state->how) {
+ case LOOK: /* -> LOOK, COPY (only if never GZIP), or GZIP */
+ if (gz_look(state) == -1)
+ return -1;
+ if (state.state->how == LOOK)
+ return 0;
+ break;
+ case COPY: /* -> COPY */
+ if (gz_load(state, state.state->out, state.state->size << 1, &(state.state->x.have))
+ == -1)
+ return -1;
+ state.state->x.next = state.state->out;
+ return 0;
+ case GZIP: /* -> GZIP or LOOK (if end of gzip stream) */
+ strm->avail_out = state.state->size << 1;
+ strm->next_out = state.state->out;
+ if (gz_decomp(state) == -1)
+ return -1;
+ }
+ } while (state.state->x.have == 0 && (!state.state->eof || strm->avail_in));
+ return 0;
+}
+
+/* Skip len uncompressed bytes of output. Return -1 on error, 0 on success. */
+local int gz_skip(state, len)
+ gz_statep state;
+ z_off64_t len;
+{
+ unsigned n;
+
+ /* skip over len bytes or reach end-of-file, whichever comes first */
+ while (len)
+ /* skip over whatever is in output buffer */
+ if (state.state->x.have) {
+ n = GT_OFF(state.state->x.have) || (z_off64_t)state.state->x.have > len ?
+ (unsigned)len : state.state->x.have;
+ state.state->x.have -= n;
+ state.state->x.next += n;
+ state.state->x.pos += n;
+ len -= n;
+ }
+
+ /* output buffer empty -- return if we're at the end of the input */
+ else if (state.state->eof && state.state->strm.avail_in == 0)
+ break;
+
+ /* need more data to skip -- load up output buffer */
+ else {
+ /* get more output, looking for header if required */
+ if (gz_fetch(state) == -1)
+ return -1;
+ }
+ return 0;
+}
+
+/* Read len bytes into buf from file, or less than len up to the end of the
+ input. Return the number of bytes read. If zero is returned, either the
+ end of file was reached, or there was an error. state.state->err must be
+ consulted in that case to determine which. */
+local z_size_t gz_read(state, buf, len)
+ gz_statep state;
+ voidp buf;
+ z_size_t len;
+{
+ z_size_t got;
+ unsigned n;
+
+ /* if len is zero, avoid unnecessary operations */
+ if (len == 0)
+ return 0;
+
+ /* process a skip request */
+ if (state.state->seek) {
+ state.state->seek = 0;
+ if (gz_skip(state, state.state->skip) == -1)
+ return 0;
+ }
+
+ /* get len bytes to buf, or less than len if at the end */
+ got = 0;
+ do {
+ /* set n to the maximum amount of len that fits in an unsigned int */
+ n = -1;
+ if (n > len)
+ n = (unsigned)len;
+
+ /* first just try copying data from the output buffer */
+ if (state.state->x.have) {
+ if (state.state->x.have < n)
+ n = state.state->x.have;
+ memcpy(buf, state.state->x.next, n);
+ state.state->x.next += n;
+ state.state->x.have -= n;
+ }
+
+ /* output buffer empty -- return if we're at the end of the input */
+ else if (state.state->eof && state.state->strm.avail_in == 0) {
+ state.state->past = 1; /* tried to read past end */
+ break;
+ }
+
+ /* need output data -- for small len or new stream load up our output
+ buffer */
+ else if (state.state->how == LOOK || n < (state.state->size << 1)) {
+ /* get more output, looking for header if required */
+ if (gz_fetch(state) == -1)
+ return 0;
+ continue; /* no progress yet -- go back to copy above */
+ /* the copy above assures that we will leave with space in the
+ output buffer, allowing at least one gzungetc() to succeed */
+ }
+
+ /* large len -- read directly into user buffer */
+ else if (state.state->how == COPY) { /* read directly */
+ if (gz_load(state, (unsigned char *)buf, n, &n) == -1)
+ return 0;
+ }
+
+ /* large len -- decompress directly into user buffer */
+ else { /* state.state->how == GZIP */
+ state.state->strm.avail_out = n;
+ state.state->strm.next_out = (unsigned char *)buf;
+ if (gz_decomp(state) == -1)
+ return 0;
+ n = state.state->x.have;
+ state.state->x.have = 0;
+ }
+
+ /* update progress */
+ len -= n;
+ buf = (char *)buf + n;
+ got += n;
+ state.state->x.pos += n;
+ } while (len);
+
+ /* return number of bytes read into user buffer */
+ return got;
+}
+
+/* -- see zlib.h -- */
+int ZEXPORT gzread(file, buf, len)
+ gzFile file;
+ voidp buf;
+ unsigned len;
+{
+ gz_statep state;
+
+ /* get internal structure */
+ if (file == NULL)
+ return -1;
+ state = (gz_statep)file;
+
+ /* check that we're reading and that there's no (serious) error */
+ if (state.state->mode != GZ_READ ||
+ (state.state->err != Z_OK && state.state->err != Z_BUF_ERROR))
+ return -1;
+
+ /* since an int is returned, make sure len fits in one, otherwise return
+ with an error (this avoids a flaw in the interface) */
+ if ((int)len < 0) {
+ gz_error(state, Z_STREAM_ERROR, "request does not fit in an int");
+ return -1;
+ }
+
+ /* read len or fewer bytes to buf */
+ len = (unsigned)gz_read(state, buf, len);
+
+ /* check for an error */
+ if (len == 0 && state.state->err != Z_OK && state.state->err != Z_BUF_ERROR)
+ return -1;
+
+ /* return the number of bytes read (this is assured to fit in an int) */
+ return (int)len;
+}
+
+/* -- see zlib.h -- */
+z_size_t ZEXPORT gzfread(buf, size, nitems, file)
+ voidp buf;
+ z_size_t size;
+ z_size_t nitems;
+ gzFile file;
+{
+ z_size_t len;
+ gz_statep state;
+
+ /* get internal structure */
+ if (file == NULL)
+ return 0;
+ state = (gz_statep)file;
+
+ /* check that we're reading and that there's no (serious) error */
+ if (state.state->mode != GZ_READ ||
+ (state.state->err != Z_OK && state.state->err != Z_BUF_ERROR))
+ return 0;
+
+ /* compute bytes to read -- error on overflow */
+ len = nitems * size;
+ if (size && len / size != nitems) {
+ gz_error(state, Z_STREAM_ERROR, "request does not fit in a size_t");
+ return 0;
+ }
+
+ /* read len or fewer bytes to buf, return the number of full items read */
+ return len ? gz_read(state, buf, len) / size : 0;
+}
+
+/* -- see zlib.h -- */
+#if ZLIB_VERNUM >= 0x1261
+#ifdef Z_PREFIX_SET
+# undef z_gzgetc
+#else
+# undef gzgetc
+#endif
+#endif
+
+#if ZLIB_VERNUM == 0x1260
+# undef gzgetc
+#endif
+
+#if ZLIB_VERNUM <= 0x1250
+ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
+ZEXTERN int ZEXPORT gzgetc_ OF((gzFile file));
+#endif
+
+int ZEXPORT gzgetc(file)
+ gzFile file;
+{
+ int ret;
+ unsigned char buf[1];
+ gz_statep state;
+
+ /* get internal structure */
+ if (file == NULL)
+ return -1;
+ state = (gz_statep)file;
+
+ /* check that we're reading and that there's no (serious) error */
+ if (state.state->mode != GZ_READ ||
+ (state.state->err != Z_OK && state.state->err != Z_BUF_ERROR))
+ return -1;
+
+ /* try output buffer (no need to check for skip request) */
+ if (state.state->x.have) {
+ state.state->x.have--;
+ state.state->x.pos++;
+ return *(state.state->x.next)++;
+ }
+
+ /* nothing there -- try gz_read() */
+ ret = (unsigned)gz_read(state, buf, 1);
+ return ret < 1 ? -1 : buf[0];
+}
+
+int ZEXPORT gzgetc_(file)
+gzFile file;
+{
+ return gzgetc(file);
+}
+
+/* -- see zlib.h -- */
+int ZEXPORT gzungetc(c, file)
+ int c;
+ gzFile file;
+{
+ gz_statep state;
+
+ /* get internal structure */
+ if (file == NULL)
+ return -1;
+ state = (gz_statep)file;
+
+ /* check that we're reading and that there's no (serious) error */
+ if (state.state->mode != GZ_READ ||
+ (state.state->err != Z_OK && state.state->err != Z_BUF_ERROR))
+ return -1;
+
+ /* process a skip request */
+ if (state.state->seek) {
+ state.state->seek = 0;
+ if (gz_skip(state, state.state->skip) == -1)
+ return -1;
+ }
+
+ /* can't push EOF */
+ if (c < 0)
+ return -1;
+
+ /* if output buffer empty, put byte at end (allows more pushing) */
+ if (state.state->x.have == 0) {
+ state.state->x.have = 1;
+ state.state->x.next = state.state->out + (state.state->size << 1) - 1;
+ state.state->x.next[0] = (unsigned char)c;
+ state.state->x.pos--;
+ state.state->past = 0;
+ return c;
+ }
+
+ /* if no room, give up (must have already done a gzungetc()) */
+ if (state.state->x.have == (state.state->size << 1)) {
+ gz_error(state, Z_DATA_ERROR, "out of room to push characters");
+ return -1;
+ }
+
+ /* slide output data if needed and insert byte before existing data */
+ if (state.state->x.next == state.state->out) {
+ unsigned char *src = state.state->out + state.state->x.have;
+ unsigned char *dest = state.state->out + (state.state->size << 1);
+ while (src > state.state->out)
+ *--dest = *--src;
+ state.state->x.next = dest;
+ }
+ state.state->x.have++;
+ state.state->x.next--;
+ state.state->x.next[0] = (unsigned char)c;
+ state.state->x.pos--;
+ state.state->past = 0;
+ return c;
+}
+
+/* -- see zlib.h -- */
+char * ZEXPORT gzgets(file, buf, len)
+ gzFile file;
+ char *buf;
+ int len;
+{
+ unsigned left, n;
+ char *str;
+ unsigned char *eol;
+ gz_statep state;
+
+ /* check parameters and get internal structure */
+ if (file == NULL || buf == NULL || len < 1)
+ return NULL;
+ state = (gz_statep)file;
+
+ /* check that we're reading and that there's no (serious) error */
+ if (state.state->mode != GZ_READ ||
+ (state.state->err != Z_OK && state.state->err != Z_BUF_ERROR))
+ return NULL;
+
+ /* process a skip request */
+ if (state.state->seek) {
+ state.state->seek = 0;
+ if (gz_skip(state, state.state->skip) == -1)
+ return NULL;
+ }
+
+ /* copy output bytes up to new line or len - 1, whichever comes first --
+ append a terminating zero to the string (we don't check for a zero in
+ the contents, let the user worry about that) */
+ str = buf;
+ left = (unsigned)len - 1;
+ if (left) do {
+ /* assure that something is in the output buffer */
+ if (state.state->x.have == 0 && gz_fetch(state) == -1)
+ return NULL; /* error */
+ if (state.state->x.have == 0) { /* end of file */
+ state.state->past = 1; /* read past end */
+ break; /* return what we have */
+ }
+
+ /* look for end-of-line in current output buffer */
+ n = state.state->x.have > left ? left : state.state->x.have;
+ eol = (unsigned char *)memchr(state.state->x.next, '\n', n);
+ if (eol != NULL)
+ n = (unsigned)(eol - state.state->x.next) + 1;
+
+ /* copy through end-of-line, or remainder if not found */
+ memcpy(buf, state.state->x.next, n);
+ state.state->x.have -= n;
+ state.state->x.next += n;
+ state.state->x.pos += n;
+ left -= n;
+ buf += n;
+ } while (left && eol == NULL);
+
+ /* return terminated string, or if nothing, end of file */
+ if (buf == str)
+ return NULL;
+ buf[0] = 0;
+ return str;
+}
+
+/* -- see zlib.h -- */
+int ZEXPORT gzdirect(file)
+ gzFile file;
+{
+ gz_statep state;
+
+ /* get internal structure */
+ if (file == NULL)
+ return 0;
+ state = (gz_statep)file;
+
+ /* if the state is not known, but we can find out, then do so (this is
+ mainly for right after a gzopen() or gzdopen()) */
+ if (state.state->mode == GZ_READ && state.state->how == LOOK && state.state->x.have == 0)
+ (void)gz_look(state);
+
+ /* return 1 if transparent, 0 if processing a gzip stream */
+ return state.state->direct;
+}
+
+/* -- see zlib.h -- */
+int ZEXPORT gzclose_r(file)
+ gzFile file;
+{
+ int ret, err;
+ gz_statep state;
+
+ /* get internal structure */
+ if (file == NULL)
+ return Z_STREAM_ERROR;
+ state = (gz_statep)file;
+
+ /* check that we're reading */
+ if (state.state->mode != GZ_READ)
+ return Z_STREAM_ERROR;
+
+ /* free memory and close file */
+ if (state.state->size) {
+ inflateEnd(&(state.state->strm));
+ free(state.state->out);
+ free(state.state->in);
+ }
+ err = state.state->err == Z_BUF_ERROR ? Z_BUF_ERROR : Z_OK;
+ gz_error(state, Z_OK, NULL);
+ free(state.state->path);
+ ret = close(state.state->fd);
+ free(state.state);
+ return ret ? Z_ERRNO : err;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-22 11:22:48 +0000