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/* gzread.c -- zlib functions for reading gzip files |
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* Copyright (C) 2004-2026 Mark Adler |
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* For conditions of distribution and use, see copyright notice in zlib.h |
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*/ |
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#include "gzguts.h" |
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/* Use read() to load a buffer -- return -1 on error, otherwise 0. Read from |
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state->fd, and update state->eof, state->err, and state->msg as appropriate. |
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This function needs to loop on read(), since read() is not guaranteed to |
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read the number of bytes requested, depending on the type of descriptor. It |
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also needs to loop to manage the fact that read() returns an int. If the |
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descriptor is non-blocking and read() returns with no data in order to avoid |
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blocking, then gz_load() will return 0 if some data has been read, or -1 if |
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no data has been read. Either way, state->again is set true to indicate a |
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non-blocking event. If errno is non-zero on return, then there was an error |
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signaled from read(). *have is set to the number of bytes read. */ |
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local int gz_load(gz_statep state, unsigned char *buf, unsigned len, |
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unsigned *have) { |
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int ret; |
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unsigned get, max = ((unsigned)-1 >> 2) + 1; |
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state->again = 0; |
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errno = 0; |
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*have = 0; |
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do { |
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get = len - *have; |
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if (get > max) |
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get = max; |
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ret = (int)read(state->fd, buf + *have, get); |
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if (ret <= 0) |
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break; |
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*have += (unsigned)ret; |
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} while (*have < len); |
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if (ret < 0) { |
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if (errno == EAGAIN || errno == EWOULDBLOCK) { |
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state->again = 1; |
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if (*have != 0) |
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return 0; |
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} |
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gz_error(state, Z_ERRNO, zstrerror()); |
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return -1; |
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} |
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if (ret == 0) |
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state->eof = 1; |
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return 0; |
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} |
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/* Load up input buffer and set eof flag if last data loaded -- return -1 on |
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error, 0 otherwise. Note that the eof flag is set when the end of the input |
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file is reached, even though there may be unused data in the buffer. Once |
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that data has been used, no more attempts will be made to read the file. |
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If strm->avail_in != 0, then the current data is moved to the beginning of |
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the input buffer, and then the remainder of the buffer is loaded with the |
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available data from the input file. */ |
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local int gz_avail(gz_statep state) { |
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unsigned got; |
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z_streamp strm = &(state->strm); |
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if (state->err != Z_OK && state->err != Z_BUF_ERROR) |
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return -1; |
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if (state->eof == 0) { |
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if (strm->avail_in) { /* copy what's there to the start */ |
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unsigned char *p = state->in; |
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unsigned const char *q = strm->next_in; |
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if (q != p) { |
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unsigned n = strm->avail_in; |
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do { |
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*p++ = *q++; |
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} while (--n); |
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} |
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} |
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if (gz_load(state, state->in + strm->avail_in, |
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state->size - strm->avail_in, &got) == -1) |
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return -1; |
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strm->avail_in += got; |
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strm->next_in = state->in; |
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} |
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return 0; |
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} |
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/* Look for gzip header, set up for inflate or copy. state->x.have must be 0. |
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If this is the first time in, allocate required memory. state->how will be |
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left unchanged if there is no more input data available, will be set to COPY |
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if there is no gzip header and direct copying will be performed, or it will |
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be set to GZIP for decompression. If direct copying, then leftover input |
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data from the input buffer will be copied to the output buffer. In that |
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case, all further file reads will be directly to either the output buffer or |
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a user buffer. If decompressing, the inflate state will be initialized. |
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gz_look() will return 0 on success or -1 on failure. */ |
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local int gz_look(gz_statep state) { |
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z_streamp strm = &(state->strm); |
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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 = (unsigned char *)malloc(state->want); |
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state->out = (unsigned char *)malloc(state->want << 1); |
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if (state->in == NULL || state->out == NULL) { |
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free(state->out); |
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free(state->in); |
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gz_error(state, Z_MEM_ERROR, "out of memory"); |
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return -1; |
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} |
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state->size = state->want; |
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/* allocate inflate memory */ |
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state->strm.zalloc = Z_NULL; |
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state->strm.zfree = Z_NULL; |
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state->strm.opaque = Z_NULL; |
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state->strm.avail_in = 0; |
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state->strm.next_in = Z_NULL; |
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if (inflateInit2(&(state->strm), 15 + 16) != Z_OK) { /* gunzip */ |
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free(state->out); |
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free(state->in); |
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state->size = 0; |
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gz_error(state, Z_MEM_ERROR, "out of memory"); |
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return -1; |
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} |
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} |
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/* if transparent reading is disabled, which would only be at the start, or |
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if we're looking for a gzip member after the first one, which is not at |
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the start, then proceed directly to look for a gzip member next */ |
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if (state->direct == -1 || state->junk == 0) { |
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inflateReset(strm); |
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state->how = GZIP; |
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state->junk = state->junk != -1; |
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state->direct = 0; |
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return 0; |
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} |
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/* otherwise we're at the start with auto-detect -- we check to see if the |
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first four bytes could be gzip header in order to decide whether or not |
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this will be a transparent read */ |
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/* load any header bytes into the input buffer -- if the input is empty, |
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then it's not an error as this is a transparent read of zero bytes */ |
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if (gz_avail(state) == -1) |
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return -1; |
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if (strm->avail_in == 0 || (state->again && strm->avail_in < 4)) |
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/* if non-blocking input stalled before getting four bytes, then |
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return and wait until a later call has accumulated enough */ |
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return 0; |
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/* see if this is (likely) gzip input -- if the first four bytes are |
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consistent with a gzip header, then go look for the first gzip member, |
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otherwise proceed to copy the input transparently */ |
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if (strm->avail_in > 3 && |
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strm->next_in[0] == 31 && strm->next_in[1] == 139 && |
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strm->next_in[2] == 8 && strm->next_in[3] < 32) { |
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inflateReset(strm); |
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state->how = GZIP; |
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state->junk = 1; |
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state->direct = 0; |
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return 0; |
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} |
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/* doing raw i/o: copy any leftover input to output -- this assumes that |
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the output buffer is larger than the input buffer, which also assures |
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space for gzungetc() */ |
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state->x.next = state->out; |
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memcpy(state->x.next, strm->next_in, strm->avail_in); |
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state->x.have = strm->avail_in; |
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strm->avail_in = 0; |
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state->how = COPY; |
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return 0; |
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} |
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/* Decompress from input to the provided next_out and avail_out in the state. |
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On return, state->x.have and state->x.next point to the just decompressed |
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data. If the gzip stream completes, state->how is reset to LOOK to look for |
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the next gzip stream or raw data, once state->x.have is depleted. Returns 0 |
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on success, -1 on failure. If EOF is reached when looking for more input to |
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complete the gzip member, then an unexpected end of file error is raised. |
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If there is no more input, but state->again is true, then EOF has not been |
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reached, and no error is raised. */ |
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local int gz_decomp(gz_statep state) { |
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int ret = Z_OK; |
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unsigned had; |
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z_streamp strm = &(state->strm); |
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/* fill output buffer up to end of deflate stream */ |
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had = strm->avail_out; |
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do { |
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/* get more input for inflate() */ |
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if (strm->avail_in == 0 && gz_avail(state) == -1) { |
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ret = state->err; |
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break; |
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} |
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if (strm->avail_in == 0) { |
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if (!state->again) |
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gz_error(state, Z_BUF_ERROR, "unexpected end of file"); |
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break; |
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} |
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/* decompress and handle errors */ |
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ret = inflate(strm, Z_NO_FLUSH); |
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if (strm->avail_out < had) |
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/* any decompressed data marks this as a real gzip stream */ |
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state->junk = 0; |
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if (ret == Z_STREAM_ERROR || ret == Z_NEED_DICT) { |
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gz_error(state, Z_STREAM_ERROR, |
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"internal error: inflate stream corrupt"); |
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break; |
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} |
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if (ret == Z_MEM_ERROR) { |
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gz_error(state, Z_MEM_ERROR, "out of memory"); |
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break; |
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} |
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if (ret == Z_DATA_ERROR) { /* deflate stream invalid */ |
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if (state->junk == 1) { /* trailing garbage is ok */ |
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strm->avail_in = 0; |
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state->eof = 1; |
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state->how = LOOK; |
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ret = Z_OK; |
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break; |
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} |
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gz_error(state, Z_DATA_ERROR, |
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strm->msg == NULL ? "compressed data error" : strm->msg); |
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break; |
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} |
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} while (strm->avail_out && ret != Z_STREAM_END); |
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/* update available output */ |
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state->x.have = had - strm->avail_out; |
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state->x.next = strm->next_out - state->x.have; |
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/* if the gzip stream completed successfully, look for another */ |
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if (ret == Z_STREAM_END) { |
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state->junk = 0; |
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state->how = LOOK; |
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return 0; |
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} |
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/* return decompression status */ |
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return ret != Z_OK ? -1 : 0; |
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} |
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/* Fetch data and put it in the output buffer. Assumes state->x.have is 0. |
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Data is either copied from the input file or decompressed from the input |
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file depending on state->how. If state->how is LOOK, then a gzip header is |
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looked for to determine whether to copy or decompress. Returns -1 on error, |
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otherwise 0. gz_fetch() will leave state->how as COPY or GZIP unless the |
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end of the input file has been reached and all data has been processed. */ |
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local int gz_fetch(gz_statep state) { |
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z_streamp strm = &(state->strm); |
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250
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do { |
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252
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switch(state->how) { |
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case LOOK: /* -> LOOK, COPY (only if never GZIP), or GZIP */ |
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if (gz_look(state) == -1) |
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return -1; |
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256
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if (state->how == LOOK) |
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return 0; |
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258
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break; |
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259
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case COPY: /* -> COPY */ |
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if (gz_load(state, state->out, state->size << 1, &(state->x.have)) |
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261
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== -1) |
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return -1; |
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state->x.next = state->out; |
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264
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return 0; |
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265
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case GZIP: /* -> GZIP or LOOK (if end of gzip stream) */ |
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266
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strm->avail_out = state->size << 1; |
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267
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strm->next_out = state->out; |
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268
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if (gz_decomp(state) == -1) |
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269
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return -1; |
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270
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break; |
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271
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default: |
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272
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gz_error(state, Z_STREAM_ERROR, "state corrupt"); |
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273
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return -1; |
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274
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} |
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275
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} while (state->x.have == 0 && (!state->eof || strm->avail_in)); |
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276
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return 0; |
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277
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} |
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278
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279
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/* Skip state->skip (> 0) uncompressed bytes of output. Return -1 on error, 0 |
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280
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on success. */ |
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281
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local int gz_skip(gz_statep state) { |
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282
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unsigned n; |
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283
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284
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/* skip over len bytes or reach end-of-file, whichever comes first */ |
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285
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do { |
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286
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/* skip over whatever is in output buffer */ |
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287
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if (state->x.have) { |
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288
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n = GT_OFF(state->x.have) || |
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289
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(z_off64_t)state->x.have > state->skip ? |
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290
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(unsigned)state->skip : state->x.have; |
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291
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state->x.have -= n; |
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292
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state->x.next += n; |
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293
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state->x.pos += n; |
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294
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state->skip -= n; |
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295
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} |
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296
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297
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/* output buffer empty -- return if we're at the end of the input */ |
|
298
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else if (state->eof && state->strm.avail_in == 0) |
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299
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break; |
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300
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|
301
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/* need more data to skip -- load up output buffer */ |
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302
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else { |
|
303
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/* get more output, looking for header if required */ |
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304
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if (gz_fetch(state) == -1) |
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305
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return -1; |
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306
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} |
|
307
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} while (state->skip); |
|
308
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return 0; |
|
309
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} |
|
310
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|
311
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/* Read len bytes into buf from file, or less than len up to the end of the |
|
312
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input. Return the number of bytes read. If zero is returned, either the end |
|
313
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of file was reached, or there was an error. state->err must be consulted in |
|
314
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that case to determine which. If there was an error, but some uncompressed |
|
315
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bytes were read before the error, then that count is returned. The error is |
|
316
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still recorded, and so is deferred until the next call. */ |
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317
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local z_size_t gz_read(gz_statep state, voidp buf, z_size_t len) { |
|
318
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z_size_t got; |
|
319
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unsigned n; |
|
320
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int err; |
|
321
|
|
|
322
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/* if len is zero, avoid unnecessary operations */ |
|
323
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if (len == 0) |
|
324
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return 0; |
|
325
|
|
|
326
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/* process a skip request */ |
|
327
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if (state->skip && gz_skip(state) == -1) |
|
328
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return 0; |
|
329
|
|
|
330
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/* get len bytes to buf, or less than len if at the end */ |
|
331
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got = 0; |
|
332
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err = 0; |
|
333
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do { |
|
334
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/* set n to the maximum amount of len that fits in an unsigned int */ |
|
335
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n = (unsigned)-1; |
|
336
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if (n > len) |
|
337
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n = (unsigned)len; |
|
338
|
|
|
339
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/* first just try copying data from the output buffer */ |
|
340
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if (state->x.have) { |
|
341
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if (state->x.have < n) |
|
342
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n = state->x.have; |
|
343
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memcpy(buf, state->x.next, n); |
|
344
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state->x.next += n; |
|
345
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state->x.have -= n; |
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346
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if (state->err != Z_OK) |
|
347
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/* caught deferred error from gz_fetch() */ |
|
348
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err = -1; |
|
349
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} |
|
350
|
|
|
351
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/* output buffer empty -- return if we're at the end of the input */ |
|
352
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else if (state->eof && state->strm.avail_in == 0) |
|
353
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break; |
|
354
|
|
|
355
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/* need output data -- for small len or new stream load up our output |
|
356
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buffer, so that gzgetc() can be fast */ |
|
357
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else if (state->how == LOOK || n < (state->size << 1)) { |
|
358
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/* get more output, looking for header if required */ |
|
359
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if (gz_fetch(state) == -1 && state->x.have == 0) |
|
360
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/* if state->x.have != 0, error will be caught after copy */ |
|
361
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err = -1; |
|
362
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continue; /* no progress yet -- go back to copy above */ |
|
363
|
/* the copy above assures that we will leave with space in the |
|
364
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output buffer, allowing at least one gzungetc() to succeed */ |
|
365
|
} |
|
366
|
|
|
367
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/* large len -- read directly into user buffer */ |
|
368
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else if (state->how == COPY) /* read directly */ |
|
369
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err = gz_load(state, (unsigned char *)buf, n, &n); |
|
370
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|
|
371
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/* large len -- decompress directly into user buffer */ |
|
372
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else { /* state->how == GZIP */ |
|
373
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state->strm.avail_out = n; |
|
374
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state->strm.next_out = (unsigned char *)buf; |
|
375
|
err = gz_decomp(state); |
|
376
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n = state->x.have; |
|
377
|
state->x.have = 0; |
|
378
|
} |
|
379
|
|
|
380
|
/* update progress */ |
|
381
|
len -= n; |
|
382
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buf = (char *)buf + n; |
|
383
|
got += n; |
|
384
|
state->x.pos += n; |
|
385
|
} while (len && !err); |
|
386
|
|
|
387
|
/* note read past eof */ |
|
388
|
if (len && state->eof) |
|
389
|
state->past = 1; |
|
390
|
|
|
391
|
/* return number of bytes read into user buffer */ |
|
392
|
return got; |
|
393
|
} |
|
394
|
|
|
395
|
/* -- see zlib.h -- */ |
|
396
|
int ZEXPORT gzread(gzFile file, voidp buf, unsigned len) { |
|
397
|
gz_statep state; |
|
398
|
|
|
399
|
/* get internal structure and check that it's for reading */ |
|
400
|
if (file == NULL) |
|
401
|
return -1; |
|
402
|
state = (gz_statep)file; |
|
403
|
if (state->mode != GZ_READ) |
|
404
|
return -1; |
|
405
|
|
|
406
|
/* check that there was no (serious) error */ |
|
407
|
if (state->err != Z_OK && state->err != Z_BUF_ERROR && !state->again) |
|
408
|
return -1; |
|
409
|
gz_error(state, Z_OK, NULL); |
|
410
|
|
|
411
|
/* since an int is returned, make sure len fits in one, otherwise return |
|
412
|
with an error (this avoids a flaw in the interface) */ |
|
413
|
if ((int)len < 0) { |
|
414
|
gz_error(state, Z_STREAM_ERROR, "request does not fit in an int"); |
|
415
|
return -1; |
|
416
|
} |
|
417
|
|
|
418
|
/* read len or fewer bytes to buf */ |
|
419
|
len = (unsigned)gz_read(state, buf, len); |
|
420
|
|
|
421
|
/* check for an error */ |
|
422
|
if (len == 0) { |
|
423
|
if (state->err != Z_OK && state->err != Z_BUF_ERROR) |
|
424
|
return -1; |
|
425
|
if (state->again) { |
|
426
|
/* non-blocking input stalled after some input was read, but no |
|
427
|
uncompressed bytes were produced -- let the application know |
|
428
|
this isn't EOF */ |
|
429
|
gz_error(state, Z_ERRNO, zstrerror()); |
|
430
|
return -1; |
|
431
|
} |
|
432
|
} |
|
433
|
|
|
434
|
/* return the number of bytes read */ |
|
435
|
return (int)len; |
|
436
|
} |
|
437
|
|
|
438
|
/* -- see zlib.h -- */ |
|
439
|
z_size_t ZEXPORT gzfread(voidp buf, z_size_t size, z_size_t nitems, |
|
440
|
gzFile file) { |
|
441
|
z_size_t len; |
|
442
|
gz_statep state; |
|
443
|
|
|
444
|
/* get internal structure and check that it's for reading */ |
|
445
|
if (file == NULL) |
|
446
|
return 0; |
|
447
|
state = (gz_statep)file; |
|
448
|
if (state->mode != GZ_READ) |
|
449
|
return 0; |
|
450
|
|
|
451
|
/* check that there was no (serious) error */ |
|
452
|
if (state->err != Z_OK && state->err != Z_BUF_ERROR && !state->again) |
|
453
|
return 0; |
|
454
|
gz_error(state, Z_OK, NULL); |
|
455
|
|
|
456
|
/* compute bytes to read -- error on overflow */ |
|
457
|
len = nitems * size; |
|
458
|
if (size && len / size != nitems) { |
|
459
|
gz_error(state, Z_STREAM_ERROR, "request does not fit in a size_t"); |
|
460
|
return 0; |
|
461
|
} |
|
462
|
|
|
463
|
/* read len or fewer bytes to buf, return the number of full items read */ |
|
464
|
return len ? gz_read(state, buf, len) / size : 0; |
|
465
|
} |
|
466
|
|
|
467
|
/* -- see zlib.h -- */ |
|
468
|
#ifdef Z_PREFIX_SET |
|
469
|
# undef z_gzgetc |
|
470
|
#else |
|
471
|
# undef gzgetc |
|
472
|
#endif |
|
473
|
int ZEXPORT gzgetc(gzFile file) { |
|
474
|
unsigned char buf[1]; |
|
475
|
gz_statep state; |
|
476
|
|
|
477
|
/* get internal structure and check that it's for reading */ |
|
478
|
if (file == NULL) |
|
479
|
return -1; |
|
480
|
state = (gz_statep)file; |
|
481
|
if (state->mode != GZ_READ) |
|
482
|
return -1; |
|
483
|
|
|
484
|
/* check that there was no (serious) error */ |
|
485
|
if (state->err != Z_OK && state->err != Z_BUF_ERROR && !state->again) |
|
486
|
return -1; |
|
487
|
gz_error(state, Z_OK, NULL); |
|
488
|
|
|
489
|
/* try output buffer (no need to check for skip request) */ |
|
490
|
if (state->x.have) { |
|
491
|
state->x.have--; |
|
492
|
state->x.pos++; |
|
493
|
return *(state->x.next)++; |
|
494
|
} |
|
495
|
|
|
496
|
/* nothing there -- try gz_read() */ |
|
497
|
return gz_read(state, buf, 1) < 1 ? -1 : buf[0]; |
|
498
|
} |
|
499
|
|
|
500
|
int ZEXPORT gzgetc_(gzFile file) { |
|
501
|
return gzgetc(file); |
|
502
|
} |
|
503
|
|
|
504
|
/* -- see zlib.h -- */ |
|
505
|
int ZEXPORT gzungetc(int c, gzFile file) { |
|
506
|
gz_statep state; |
|
507
|
|
|
508
|
/* get internal structure and check that it's for reading */ |
|
509
|
if (file == NULL) |
|
510
|
return -1; |
|
511
|
state = (gz_statep)file; |
|
512
|
if (state->mode != GZ_READ) |
|
513
|
return -1; |
|
514
|
|
|
515
|
/* in case this was just opened, set up the input buffer */ |
|
516
|
if (state->how == LOOK && state->x.have == 0) |
|
517
|
(void)gz_look(state); |
|
518
|
|
|
519
|
/* check that there was no (serious) error */ |
|
520
|
if (state->err != Z_OK && state->err != Z_BUF_ERROR && !state->again) |
|
521
|
return -1; |
|
522
|
gz_error(state, Z_OK, NULL); |
|
523
|
|
|
524
|
/* process a skip request */ |
|
525
|
if (state->skip && gz_skip(state) == -1) |
|
526
|
return -1; |
|
527
|
|
|
528
|
/* can't push EOF */ |
|
529
|
if (c < 0) |
|
530
|
return -1; |
|
531
|
|
|
532
|
/* if output buffer empty, put byte at end (allows more pushing) */ |
|
533
|
if (state->x.have == 0) { |
|
534
|
state->x.have = 1; |
|
535
|
state->x.next = state->out + (state->size << 1) - 1; |
|
536
|
state->x.next[0] = (unsigned char)c; |
|
537
|
state->x.pos--; |
|
538
|
state->past = 0; |
|
539
|
return c; |
|
540
|
} |
|
541
|
|
|
542
|
/* if no room, give up (must have already done a gzungetc()) */ |
|
543
|
if (state->x.have == (state->size << 1)) { |
|
544
|
gz_error(state, Z_DATA_ERROR, "out of room to push characters"); |
|
545
|
return -1; |
|
546
|
} |
|
547
|
|
|
548
|
/* slide output data if needed and insert byte before existing data */ |
|
549
|
if (state->x.next == state->out) { |
|
550
|
unsigned char *src = state->out + state->x.have; |
|
551
|
unsigned char *dest = state->out + (state->size << 1); |
|
552
|
|
|
553
|
while (src > state->out) |
|
554
|
*--dest = *--src; |
|
555
|
state->x.next = dest; |
|
556
|
} |
|
557
|
state->x.have++; |
|
558
|
state->x.next--; |
|
559
|
state->x.next[0] = (unsigned char)c; |
|
560
|
state->x.pos--; |
|
561
|
state->past = 0; |
|
562
|
return c; |
|
563
|
} |
|
564
|
|
|
565
|
/* -- see zlib.h -- */ |
|
566
|
char * ZEXPORT gzgets(gzFile file, char *buf, int len) { |
|
567
|
unsigned left, n; |
|
568
|
char *str; |
|
569
|
unsigned char *eol; |
|
570
|
gz_statep state; |
|
571
|
|
|
572
|
/* check parameters, get internal structure, and check that it's for |
|
573
|
reading */ |
|
574
|
if (file == NULL || buf == NULL || len < 1) |
|
575
|
return NULL; |
|
576
|
state = (gz_statep)file; |
|
577
|
if (state->mode != GZ_READ) |
|
578
|
return NULL; |
|
579
|
|
|
580
|
/* check that there was no (serious) error */ |
|
581
|
if (state->err != Z_OK && state->err != Z_BUF_ERROR && !state->again) |
|
582
|
return NULL; |
|
583
|
gz_error(state, Z_OK, NULL); |
|
584
|
|
|
585
|
/* process a skip request */ |
|
586
|
if (state->skip && gz_skip(state) == -1) |
|
587
|
return NULL; |
|
588
|
|
|
589
|
/* copy output up to a new line, len-1 bytes, or there is no more output, |
|
590
|
whichever comes first */ |
|
591
|
str = buf; |
|
592
|
left = (unsigned)len - 1; |
|
593
|
if (left) do { |
|
594
|
/* assure that something is in the output buffer */ |
|
595
|
if (state->x.have == 0 && gz_fetch(state) == -1) |
|
596
|
break; /* error */ |
|
597
|
if (state->x.have == 0) { /* end of file */ |
|
598
|
state->past = 1; /* read past end */ |
|
599
|
break; /* return what we have */ |
|
600
|
} |
|
601
|
|
|
602
|
/* look for end-of-line in current output buffer */ |
|
603
|
n = state->x.have > left ? left : state->x.have; |
|
604
|
eol = (unsigned char *)memchr(state->x.next, '\n', n); |
|
605
|
if (eol != NULL) |
|
606
|
n = (unsigned)(eol - state->x.next) + 1; |
|
607
|
|
|
608
|
/* copy through end-of-line, or remainder if not found */ |
|
609
|
memcpy(buf, state->x.next, n); |
|
610
|
state->x.have -= n; |
|
611
|
state->x.next += n; |
|
612
|
state->x.pos += n; |
|
613
|
left -= n; |
|
614
|
buf += n; |
|
615
|
} while (left && eol == NULL); |
|
616
|
|
|
617
|
/* append a terminating zero to the string (we don't check for a zero in |
|
618
|
the contents, let the user worry about that) -- return the terminated |
|
619
|
string, or if nothing was read, NULL */ |
|
620
|
if (buf == str) |
|
621
|
return NULL; |
|
622
|
buf[0] = 0; |
|
623
|
return str; |
|
624
|
} |
|
625
|
|
|
626
|
/* -- see zlib.h -- */ |
|
627
|
int ZEXPORT gzdirect(gzFile file) { |
|
628
|
gz_statep state; |
|
629
|
|
|
630
|
/* get internal structure */ |
|
631
|
if (file == NULL) |
|
632
|
return 0; |
|
633
|
state = (gz_statep)file; |
|
634
|
|
|
635
|
/* if the state is not known, but we can find out, then do so (this is |
|
636
|
mainly for right after a gzopen() or gzdopen()) */ |
|
637
|
if (state->mode == GZ_READ && state->how == LOOK && state->x.have == 0) |
|
638
|
(void)gz_look(state); |
|
639
|
|
|
640
|
/* return 1 if transparent, 0 if processing a gzip stream */ |
|
641
|
return state->direct == 1; |
|
642
|
} |
|
643
|
|
|
644
|
/* -- see zlib.h -- */ |
|
645
|
int ZEXPORT gzclose_r(gzFile file) { |
|
646
|
int ret, err; |
|
647
|
gz_statep state; |
|
648
|
|
|
649
|
/* get internal structure and check that it's for reading */ |
|
650
|
if (file == NULL) |
|
651
|
return Z_STREAM_ERROR; |
|
652
|
state = (gz_statep)file; |
|
653
|
if (state->mode != GZ_READ) |
|
654
|
return Z_STREAM_ERROR; |
|
655
|
|
|
656
|
/* free memory and close file */ |
|
657
|
if (state->size) { |
|
658
|
inflateEnd(&(state->strm)); |
|
659
|
free(state->out); |
|
660
|
free(state->in); |
|
661
|
} |
|
662
|
err = state->err == Z_BUF_ERROR ? Z_BUF_ERROR : Z_OK; |
|
663
|
gz_error(state, Z_OK, NULL); |
|
664
|
free(state->path); |
|
665
|
ret = close(state->fd); |
|
666
|
free(state); |
|
667
|
return ret ? Z_ERRNO : err; |
|
668
|
} |
|
669
|
|