zlib: update to 1.2.11

1 files changed, 569 insertions, 509 deletions

diff --git a/libs/zlib/src/gzread.c b/libs/zlib/src/gzread.c
index cd994301a8..956b91ea7d 100644
--- a/libs/zlib/src/gzread.c
+++ b/libs/zlib/src/gzread.c
@@ -1,381 +1,441 @@
 /* gzread.c -- zlib functions for reading gzip files
- * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013 Mark Adler
+ * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013, 2016 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
 #include "gzguts.h"
 
- /* Local functions */
+/* 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->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. */
+   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;
+    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;
+    int ret;
+    unsigned get, max = ((unsigned)-1 >> 2) + 1;
+
+    *have = 0;
+    do {
+        get = len - *have;
+        if (get > max)
+            get = max;
+        ret = read(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->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. */
+   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;
+    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;
+    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. */
+   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;
+    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;
+    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) {
+            free(state->out);
+            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. */
+   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;
+    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;
+    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.  */
+   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;
+    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;
+    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;
+    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;
+    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;
+}
+
+/* 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->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->seek) {
+        state->seek = 0;
+        if (gz_skip(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 = len;
+
+        /* first just try copying data from the output buffer */
+        if (state->x.have) {
+            if (state->x.have < n)
+                n = 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 && state->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 || n < (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->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->how == GZIP */
+            state->strm.avail_out = n;
+            state->strm.next_out = (unsigned char *)buf;
+            if (gz_decomp(state) == -1)
+                return 0;
+            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 */
+    return got;
 }
 
 /* -- see zlib.h -- */
 int ZEXPORT gzread(file, buf, len)
-gzFile file;
-voidp buf;
-unsigned 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;
+    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;
+
+    /* 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 = gz_read(state, buf, len);
+
+    /* check for an error */
+    if (len == 0 && state->err != Z_OK && 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->mode != GZ_READ ||
+            (state->err != Z_OK && 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 -- */
@@ -385,210 +445,210 @@ unsigned len;
 #  undef gzgetc
 #endif
 int ZEXPORT gzgetc(file)
-gzFile 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 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 gz_read() */
+    ret = gz_read(state, buf, 1);
+    return ret < 1 ? -1 : buf[0];
 }
 
 int ZEXPORT gzgetc_(file)
 gzFile file;
 {
-	return gzgetc(file);
+    return gzgetc(file);
 }
 
 /* -- see zlib.h -- */
 int ZEXPORT gzungetc(c, file)
-int c;
-gzFile 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;
+    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] = (unsigned char)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] = (unsigned char)c;
+    state->x.pos--;
+    state->past = 0;
+    return c;
 }
 
 /* -- see zlib.h -- */
 char * ZEXPORT gzgets(file, buf, len)
-gzFile file;
-char *buf;
-int 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;
+    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;
+    gzFile file;
 {
-	gz_statep state;
+    gz_statep state;
 
-	/* get internal structure */
-	if (file == NULL)
-		return 0;
-	state = (gz_statep)file;
+    /* 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);
+    /* 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;
+    /* return 1 if transparent, 0 if processing a gzip stream */
+    return state->direct;
 }
 
 /* -- see zlib.h -- */
 int ZEXPORT gzclose_r(file)
-gzFile 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;
+    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;
 }