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-rw-r--r--mysql/zlib/gzread.c653
1 files changed, 653 insertions, 0 deletions
diff --git a/mysql/zlib/gzread.c b/mysql/zlib/gzread.c
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--- /dev/null
+++ b/mysql/zlib/gzread.c
@@ -0,0 +1,653 @@
+/* gzread.c -- zlib functions for reading gzip files
+ * Copyright (C) 2004, 2005, 2010 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#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_next4 OF((gz_statep, unsigned long *));
+local int gz_head OF((gz_statep));
+local int gz_decomp OF((gz_statep));
+local int gz_make OF((gz_statep));
+local int gz_skip OF((gz_statep, z_off64_t));
+
+/* Use read() to load a buffer -- return -1 on error, otherwise 0. Read from
+ state->fd, and update state->eof, state->err, and 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;
+{
+ int ret;
+
+ *have = 0;
+ do {
+ ret = read(state->fd, buf + *have, len - *have);
+ if (ret <= 0)
+ break;
+ *have += ret;
+ } while (*have < len);
+ if (ret < 0) {
+ gz_error(state, Z_ERRNO, zstrerror());
+ return -1;
+ }
+ if (ret == 0)
+ 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.
+ gz_avail() assumes that strm->avail_in == 0. */
+local int gz_avail(state)
+ gz_statep state;
+{
+ z_streamp strm = &(state->strm);
+
+ if (state->err != Z_OK)
+ return -1;
+ if (state->eof == 0) {
+ if (gz_load(state, state->in, state->size,
+ (unsigned *)&(strm->avail_in)) == -1)
+ return -1;
+ strm->next_in = state->in;
+ }
+ return 0;
+}
+
+/* Get next byte from input, or -1 if end or error. */
+#define NEXT() ((strm->avail_in == 0 && gz_avail(state) == -1) ? -1 : \
+ (strm->avail_in == 0 ? -1 : \
+ (strm->avail_in--, *(strm->next_in)++)))
+
+/* Get a four-byte little-endian integer and return 0 on success and the value
+ in *ret. Otherwise -1 is returned and *ret is not modified. */
+local int gz_next4(state, ret)
+ gz_statep state;
+ unsigned long *ret;
+{
+ int ch;
+ unsigned long val;
+ z_streamp strm = &(state->strm);
+
+ val = NEXT();
+ val += (unsigned)NEXT() << 8;
+ val += (unsigned long)NEXT() << 16;
+ ch = NEXT();
+ if (ch == -1)
+ return -1;
+ val += (unsigned long)ch << 24;
+ *ret = val;
+ return 0;
+}
+
+/* Look for gzip header, set up for inflate or copy. state->have must be zero.
+ If this is the first time in, allocate required memory. 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, and the gzip header will be skipped so
+ that the next available input data is the raw deflate stream. 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 and the check value will be initialized. gz_head() will return 0 on
+ success or -1 on failure. Failures may include read errors or gzip header
+ errors. */
+local int gz_head(state)
+ gz_statep state;
+{
+ z_streamp strm = &(state->strm);
+ int flags;
+ unsigned len;
+
+ /* allocate read buffers and inflate memory */
+ if (state->size == 0) {
+ /* allocate buffers */
+ state->in = malloc(state->want);
+ state->out = malloc(state->want << 1);
+ if (state->in == NULL || state->out == NULL) {
+ if (state->out != NULL)
+ free(state->out);
+ if (state->in != NULL)
+ free(state->in);
+ gz_error(state, Z_MEM_ERROR, "out of memory");
+ return -1;
+ }
+ state->size = state->want;
+
+ /* allocate inflate memory */
+ state->strm.zalloc = Z_NULL;
+ state->strm.zfree = Z_NULL;
+ state->strm.opaque = Z_NULL;
+ state->strm.avail_in = 0;
+ state->strm.next_in = Z_NULL;
+ if (inflateInit2(&(state->strm), -15) != Z_OK) { /* raw inflate */
+ free(state->out);
+ free(state->in);
+ state->size = 0;
+ gz_error(state, Z_MEM_ERROR, "out of memory");
+ return -1;
+ }
+ }
+
+ /* get some data in the input buffer */
+ if (strm->avail_in == 0) {
+ if (gz_avail(state) == -1)
+ return -1;
+ if (strm->avail_in == 0)
+ return 0;
+ }
+
+ /* look for the gzip magic header bytes 31 and 139 */
+ if (strm->next_in[0] == 31) {
+ strm->avail_in--;
+ strm->next_in++;
+ if (strm->avail_in == 0 && gz_avail(state) == -1)
+ return -1;
+ if (strm->avail_in && strm->next_in[0] == 139) {
+ /* we have a gzip header, woo hoo! */
+ strm->avail_in--;
+ strm->next_in++;
+
+ /* skip rest of header */
+ if (NEXT() != 8) { /* compression method */
+ gz_error(state, Z_DATA_ERROR, "unknown compression method");
+ return -1;
+ }
+ flags = NEXT();
+ if (flags & 0xe0) { /* reserved flag bits */
+ gz_error(state, Z_DATA_ERROR, "unknown header flags set");
+ return -1;
+ }
+ NEXT(); /* modification time */
+ NEXT();
+ NEXT();
+ NEXT();
+ NEXT(); /* extra flags */
+ NEXT(); /* operating system */
+ if (flags & 4) { /* extra field */
+ len = (unsigned)NEXT();
+ len += (unsigned)NEXT() << 8;
+ while (len--)
+ if (NEXT() < 0)
+ break;
+ }
+ if (flags & 8) /* file name */
+ while (NEXT() > 0)
+ ;
+ if (flags & 16) /* comment */
+ while (NEXT() > 0)
+ ;
+ if (flags & 2) { /* header crc */
+ NEXT();
+ NEXT();
+ }
+ /* an unexpected end of file is not checked for here -- it will be
+ noticed on the first request for uncompressed data */
+
+ /* set up for decompression */
+ inflateReset(strm);
+ strm->adler = crc32(0L, Z_NULL, 0);
+ state->how = GZIP;
+ state->direct = 0;
+ return 0;
+ }
+ else {
+ /* not a gzip file -- save first byte (31) and fall to raw i/o */
+ state->out[0] = 31;
+ state->have = 1;
+ }
+ }
+
+ /* doing raw i/o, save start of raw data for seeking, 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->raw = state->pos;
+ state->next = state->out;
+ if (strm->avail_in) {
+ memcpy(state->next + state->have, strm->next_in, strm->avail_in);
+ state->have += strm->avail_in;
+ strm->avail_in = 0;
+ }
+ state->how = COPY;
+ state->direct = 1;
+ return 0;
+}
+
+/* Decompress from input to the provided next_out and avail_out in the state.
+ If the end of the compressed data is reached, then verify the gzip trailer
+ check value and length (modulo 2^32). state->have and state->next are set
+ to point to the just decompressed data, and the crc is updated. If the
+ trailer is verified, state->how is reset to LOOK to look for the next gzip
+ stream or raw data, once state->have is depleted. Returns 0 on success, -1
+ on failure. Failures may include invalid compressed data or a failed gzip
+ trailer verification. */
+local int gz_decomp(state)
+ gz_statep state;
+{
+ int ret;
+ unsigned had;
+ unsigned long crc, len;
+ z_streamp strm = &(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_DATA_ERROR, "unexpected end of file");
+ return -1;
+ }
+
+ /* 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 and crc check value */
+ state->have = had - strm->avail_out;
+ state->next = strm->next_out - state->have;
+ strm->adler = crc32(strm->adler, state->next, state->have);
+
+ /* check gzip trailer if at end of deflate stream */
+ if (ret == Z_STREAM_END) {
+ if (gz_next4(state, &crc) == -1 || gz_next4(state, &len) == -1) {
+ gz_error(state, Z_DATA_ERROR, "unexpected end of file");
+ return -1;
+ }
+ if (crc != strm->adler) {
+ gz_error(state, Z_DATA_ERROR, "incorrect data check");
+ return -1;
+ }
+ if (len != (strm->total_out & 0xffffffffL)) {
+ gz_error(state, Z_DATA_ERROR, "incorrect length check");
+ return -1;
+ }
+ state->how = LOOK; /* ready for next stream, once have is 0 (leave
+ state->direct unchanged to remember how) */
+ }
+
+ /* good decompression */
+ return 0;
+}
+
+/* Make data and put in the output buffer. Assumes that state->have == 0.
+ Data is either copied from the input file or decompressed from the input
+ file depending on state->how. If state->how is LOOK, then a gzip header is
+ looked for (and skipped if found) to determine wither to copy or decompress.
+ Returns -1 on error, otherwise 0. gz_make() will leave state->have as COPY
+ or GZIP unless the end of the input file has been reached and all data has
+ been processed. */
+local int gz_make(state)
+ gz_statep state;
+{
+ z_streamp strm = &(state->strm);
+
+ if (state->how == LOOK) { /* look for gzip header */
+ if (gz_head(state) == -1)
+ return -1;
+ if (state->have) /* got some data from gz_head() */
+ return 0;
+ }
+ if (state->how == COPY) { /* straight copy */
+ if (gz_load(state, state->out, state->size << 1, &(state->have)) == -1)
+ return -1;
+ state->next = state->out;
+ }
+ else if (state->how == GZIP) { /* decompress */
+ strm->avail_out = state->size << 1;
+ strm->next_out = state->out;
+ if (gz_decomp(state) == -1)
+ return -1;
+ }
+ 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->have) {
+ n = GT_OFF(state->have) || (z_off64_t)state->have > len ?
+ (unsigned)len : state->have;
+ state->have -= n;
+ state->next += n;
+ state->pos += n;
+ len -= n;
+ }
+
+ /* output buffer empty -- return if we're at the end of the input */
+ else if (state->eof && 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_make(state) == -1)
+ return -1;
+ }
+ return 0;
+}
+
+/* -- see zlib.h -- */
+int ZEXPORT gzread(file, buf, len)
+ gzFile file;
+ voidp buf;
+ unsigned len;
+{
+ unsigned got, n;
+ gz_statep state;
+ z_streamp strm;
+
+ /* get internal structure */
+ if (file == NULL)
+ return -1;
+ state = (gz_statep)file;
+ strm = &(state->strm);
+
+ /* check that we're reading and that there's no error */
+ if (state->mode != GZ_READ || state->err != Z_OK)
+ return -1;
+
+ /* since an int is returned, make sure len fits in one, otherwise return
+ with an error (this avoids the flaw in the interface) */
+ if ((int)len < 0) {
+ gz_error(state, Z_BUF_ERROR, "requested length does not fit in int");
+ return -1;
+ }
+
+ /* if len is zero, avoid unnecessary operations */
+ if (len == 0)
+ return 0;
+
+ /* process a skip request */
+ if (state->seek) {
+ state->seek = 0;
+ if (gz_skip(state, state->skip) == -1)
+ return -1;
+ }
+
+ /* get len bytes to buf, or less than len if at the end */
+ got = 0;
+ do {
+ /* first just try copying data from the output buffer */
+ if (state->have) {
+ n = state->have > len ? len : state->have;
+ memcpy(buf, state->next, n);
+ state->next += n;
+ state->have -= n;
+ }
+
+ /* output buffer empty -- return if we're at the end of the input */
+ else if (state->eof && strm->avail_in == 0)
+ break;
+
+ /* need output data -- for small len or new stream load up our output
+ buffer */
+ else if (state->how == LOOK || len < (state->size << 1)) {
+ /* get more output, looking for header if required */
+ if (gz_make(state) == -1)
+ return -1;
+ continue; /* no progress yet -- go back to memcpy() 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->how == COPY) { /* read directly */
+ if (gz_load(state, buf, len, &n) == -1)
+ return -1;
+ }
+
+ /* large len -- decompress directly into user buffer */
+ else { /* state->how == GZIP */
+ strm->avail_out = len;
+ strm->next_out = buf;
+ if (gz_decomp(state) == -1)
+ return -1;
+ n = state->have;
+ state->have = 0;
+ }
+
+ /* update progress */
+ len -= n;
+ buf = (char *)buf + n;
+ got += n;
+ state->pos += n;
+ } while (len);
+
+ /* return number of bytes read into user buffer (will fit in int) */
+ return (int)got;
+}
+
+/* -- see zlib.h -- */
+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 error */
+ if (state->mode != GZ_READ || state->err != Z_OK)
+ return -1;
+
+ /* try output buffer (no need to check for skip request) */
+ if (state->have) {
+ state->have--;
+ state->pos++;
+ return *(state->next)++;
+ }
+
+ /* nothing there -- try gzread() */
+ ret = gzread(file, buf, 1);
+ return ret < 1 ? -1 : buf[0];
+}
+
+/* -- 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 error */
+ if (state->mode != GZ_READ || state->err != Z_OK)
+ return -1;
+
+ /* process a skip request */
+ if (state->seek) {
+ state->seek = 0;
+ if (gz_skip(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->have == 0) {
+ state->have = 1;
+ state->next = state->out + (state->size << 1) - 1;
+ state->next[0] = c;
+ state->pos--;
+ return c;
+ }
+
+ /* if no room, give up (must have already done a gzungetc()) */
+ if (state->have == (state->size << 1)) {
+ gz_error(state, Z_BUF_ERROR, "out of room to push characters");
+ return -1;
+ }
+
+ /* slide output data if needed and insert byte before existing data */
+ if (state->next == state->out) {
+ unsigned char *src = state->out + state->have;
+ unsigned char *dest = state->out + (state->size << 1);
+ while (src > state->out)
+ *--dest = *--src;
+ state->next = dest;
+ }
+ state->have++;
+ state->next--;
+ state->next[0] = c;
+ state->pos--;
+ 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 error */
+ if (state->mode != GZ_READ || state->err != Z_OK)
+ return NULL;
+
+ /* process a skip request */
+ if (state->seek) {
+ state->seek = 0;
+ if (gz_skip(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->have == 0) {
+ if (gz_make(state) == -1)
+ return NULL; /* error */
+ if (state->have == 0) { /* end of file */
+ if (buf == str) /* got bupkus */
+ return NULL;
+ break; /* got something -- return it */
+ }
+ }
+
+ /* look for end-of-line in current output buffer */
+ n = state->have > left ? left : state->have;
+ eol = memchr(state->next, '\n', n);
+ if (eol != NULL)
+ n = (unsigned)(eol - state->next) + 1;
+
+ /* copy through end-of-line, or remainder if not found */
+ memcpy(buf, state->next, n);
+ state->have -= n;
+ state->next += n;
+ state->pos += n;
+ left -= n;
+ buf += n;
+ } while (left && eol == NULL);
+
+ /* found end-of-line or out of space -- terminate string and return it */
+ 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;
+
+ /* check that we're reading */
+ if (state->mode != GZ_READ)
+ return 0;
+
+ /* 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->how == LOOK && state->have == 0)
+ (void)gz_head(state);
+
+ /* return 1 if reading direct, 0 if decompressing a gzip stream */
+ return state->direct;
+}
+
+/* -- see zlib.h -- */
+int ZEXPORT gzclose_r(file)
+ gzFile file;
+{
+ int ret;
+ gz_statep state;
+
+ /* get internal structure */
+ if (file == NULL)
+ return Z_STREAM_ERROR;
+ state = (gz_statep)file;
+
+ /* check that we're reading */
+ if (state->mode != GZ_READ)
+ return Z_STREAM_ERROR;
+
+ /* free memory and close file */
+ if (state->size) {
+ inflateEnd(&(state->strm));
+ free(state->out);
+ free(state->in);
+ }
+ gz_error(state, Z_OK, NULL);
+ free(state->path);
+ ret = close(state->fd);
+ free(state);
+ return ret ? Z_ERRNO : Z_OK;
+}
generated by cgit v1.1 at 2024-11-21 18:24:45 +0000