+++ /dev/null
-/* gzread.c -- zlib functions for reading gzip files
- * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013 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_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));
-
-/* 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.
- 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->strm);
-
- if (state->err != Z_OK && state->err != Z_BUF_ERROR)
- return -1;
- if (state->eof == 0) {
- if (strm->avail_in) { /* copy what's there to the start */
- unsigned char *p = state->in;
- unsigned const char *q = strm->next_in;
- unsigned n = strm->avail_in;
- do {
- *p++ = *q++;
- } while (--n);
- }
- if (gz_load(state, state->in + strm->avail_in,
- state->size - strm->avail_in, &got) == -1)
- return -1;
- strm->avail_in += got;
- strm->next_in = state->in;
- }
- return 0;
-}
-
-/* Look for gzip header, set up for inflate or copy. state->x.have must be 0.
- 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. 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->strm);
-
- /* allocate read buffers and inflate memory */
- if (state->size == 0) {
- /* allocate buffers */
- state->in = (unsigned char *)malloc(state->want);
- state->out = (unsigned char *)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 + 16) != Z_OK) { /* gunzip */
- free(state->out);
- free(state->in);
- 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) {
- inflateReset(strm);
- state->how = GZIP;
- 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->direct == 0) {
- strm->avail_in = 0;
- state->eof = 1;
- 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->x.next = state->out;
- if (strm->avail_in) {
- memcpy(state->x.next, strm->next_in, strm->avail_in);
- state->x.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.
- On return, state->x.have and state->x.next point to the just decompressed
- data. If the gzip stream completes, state->how is reset to LOOK to look for
- the next gzip stream or raw data, once 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->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->x.have = had - strm->avail_out;
- state->x.next = strm->next_out - state->x.have;
-
- /* if the gzip stream completed successfully, look for another */
- if (ret == Z_STREAM_END)
- state->how = LOOK;
-
- /* good decompression */
- return 0;
-}
-
-/* Fetch data and put it in the output buffer. Assumes state->x.have is 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 to determine whether to copy or decompress. Returns -1 on error,
- otherwise 0. gz_fetch() will leave 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->strm);
-
- do {
- switch(state->how) {
- case LOOK: /* -> LOOK, COPY (only if never GZIP), or GZIP */
- if (gz_look(state) == -1)
- return -1;
- if (state->how == LOOK)
- return 0;
- break;
- case COPY: /* -> COPY */
- if (gz_load(state, state->out, state->size << 1, &(state->x.have))
- == -1)
- return -1;
- state->x.next = state->out;
- return 0;
- case GZIP: /* -> GZIP or LOOK (if end of gzip stream) */
- strm->avail_out = state->size << 1;
- strm->next_out = state->out;
- if (gz_decomp(state) == -1)
- return -1;
- }
- } while (state->x.have == 0 && (!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->x.have) {
- n = GT_OFF(state->x.have) || (z_off64_t)state->x.have > len ?
- (unsigned)len : state->x.have;
- state->x.have -= n;
- state->x.next += n;
- state->x.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_fetch(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 (serious) error */
- if (state->mode != GZ_READ ||
- (state->err != Z_OK && 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 the flaw in the interface) */
- if ((int)len < 0) {
- gz_error(state, Z_DATA_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->x.have) {
- n = state->x.have > len ? len : state->x.have;
- memcpy(buf, state->x.next, n);
- state->x.next += n;
- state->x.have -= n;
- }
-
- /* output buffer empty -- return if we're at the end of the input */
- else if (state->eof && strm->avail_in == 0) {
- 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->how == LOOK || len < (state->size << 1)) {
- /* get more output, looking for header if required */
- if (gz_fetch(state) == -1)
- return -1;
- 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->how == COPY) { /* read directly */
- if (gz_load(state, (unsigned char *)buf, len, &n) == -1)
- return -1;
- }
-
- /* large len -- decompress directly into user buffer */
- else { /* state->how == GZIP */
- strm->avail_out = len;
- strm->next_out = (unsigned char *)buf;
- if (gz_decomp(state) == -1)
- return -1;
- n = state->x.have;
- state->x.have = 0;
- }
-
- /* update progress */
- len -= n;
- buf = (char *)buf + n;
- got += n;
- state->x.pos += n;
- } while (len);
-
- /* return number of bytes read into user buffer (will fit in int) */
- return (int)got;
-}
-
-/* -- see zlib.h -- */
-#ifdef Z_PREFIX_SET
-# undef z_gzgetc
-#else
-# undef gzgetc
-#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->mode != GZ_READ ||
- (state->err != Z_OK && state->err != Z_BUF_ERROR))
- return -1;
-
- /* try output buffer (no need to check for skip request) */
- if (state->x.have) {
- state->x.have--;
- state->x.pos++;
- return *(state->x.next)++;
- }
-
- /* nothing there -- try gzread() */
- ret = gzread(file, 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->mode != GZ_READ ||
- (state->err != Z_OK && state->err != Z_BUF_ERROR))
- 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->x.have == 0) {
- state->x.have = 1;
- state->x.next = state->out + (state->size << 1) - 1;
- state->x.next[0] = c;
- state->x.pos--;
- state->past = 0;
- return c;
- }
-
- /* if no room, give up (must have already done a gzungetc()) */
- if (state->x.have == (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->x.next == state->out) {
- unsigned char *src = state->out + state->x.have;
- unsigned char *dest = state->out + (state->size << 1);
- while (src > state->out)
- *--dest = *--src;
- state->x.next = dest;
- }
- state->x.have++;
- state->x.next--;
- state->x.next[0] = c;
- state->x.pos--;
- 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->mode != GZ_READ ||
- (state->err != Z_OK && state->err != Z_BUF_ERROR))
- 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->x.have == 0 && gz_fetch(state) == -1)
- return NULL; /* error */
- if (state->x.have == 0) { /* end of file */
- state->past = 1; /* read past end */
- break; /* return what we have */
- }
-
- /* look for end-of-line in current output buffer */
- n = state->x.have > left ? left : state->x.have;
- eol = (unsigned char *)memchr(state->x.next, '\n', n);
- if (eol != NULL)
- n = (unsigned)(eol - state->x.next) + 1;
-
- /* copy through end-of-line, or remainder if not found */
- memcpy(buf, state->x.next, n);
- state->x.have -= n;
- state->x.next += n;
- 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->mode == GZ_READ && state->how == LOOK && state->x.have == 0)
- (void)gz_look(state);
-
- /* return 1 if transparent, 0 if processing a gzip stream */
- return 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->mode != GZ_READ)
- return Z_STREAM_ERROR;
-
- /* free memory and close file */
- if (state->size) {
- inflateEnd(&(state->strm));
- free(state->out);
- free(state->in);
- }
- err = state->err == Z_BUF_ERROR ? Z_BUF_ERROR : Z_OK;
- gz_error(state, Z_OK, NULL);
- free(state->path);
- ret = close(state->fd);
- free(state);
- return ret ? Z_ERRNO : err;
-}
projects / ossec-hids.git / blobdiff