-/* gzread.c -- zlib functions for reading gzip files\r
- * Copyright (C) 2004, 2005, 2010 Mark Adler\r
- * For conditions of distribution and use, see copyright notice in zlib.h\r
- */\r
-\r
-#include "gzguts.h"\r
-\r
-/* Local functions */\r
-local int gz_load OF((gz_statep, unsigned char *, unsigned, unsigned *));\r
-local int gz_avail OF((gz_statep));\r
-local int gz_next4 OF((gz_statep, unsigned long *));\r
-local int gz_head OF((gz_statep));\r
-local int gz_decomp OF((gz_statep));\r
-local int gz_make OF((gz_statep));\r
-local int gz_skip OF((gz_statep, z_off64_t));\r
-\r
-/* Use read() to load a buffer -- return -1 on error, otherwise 0. Read from\r
- state->fd, and update state->eof, state->err, and state->msg as appropriate.\r
- This function needs to loop on read(), since read() is not guaranteed to\r
- read the number of bytes requested, depending on the type of descriptor. */\r
-local int gz_load(state, buf, len, have)\r
- gz_statep state;\r
- unsigned char *buf;\r
- unsigned len;\r
- unsigned *have;\r
-{\r
- int ret;\r
-\r
- *have = 0;\r
- do {\r
- ret = read(state->fd, buf + *have, len - *have);\r
- if (ret <= 0)\r
- break;\r
- *have += ret;\r
- } while (*have < len);\r
- if (ret < 0) {\r
- gz_error(state, Z_ERRNO, zstrerror());\r
- return -1;\r
- }\r
- if (ret == 0)\r
- state->eof = 1;\r
- return 0;\r
-}\r
-\r
-/* Load up input buffer and set eof flag if last data loaded -- return -1 on\r
- error, 0 otherwise. Note that the eof flag is set when the end of the input\r
- file is reached, even though there may be unused data in the buffer. Once\r
- that data has been used, no more attempts will be made to read the file.\r
- gz_avail() assumes that strm->avail_in == 0. */\r
-local int gz_avail(state)\r
- gz_statep state;\r
-{\r
- z_streamp strm = &(state->strm);\r
-\r
- if (state->err != Z_OK)\r
- return -1;\r
- if (state->eof == 0) {\r
- if (gz_load(state, state->in, state->size,\r
- (unsigned *)&(strm->avail_in)) == -1)\r
- return -1;\r
- strm->next_in = state->in;\r
- }\r
- return 0;\r
-}\r
-\r
-/* Get next byte from input, or -1 if end or error. */\r
-#define NEXT() ((strm->avail_in == 0 && gz_avail(state) == -1) ? -1 : \\r
- (strm->avail_in == 0 ? -1 : \\r
- (strm->avail_in--, *(strm->next_in)++)))\r
-\r
-/* Get a four-byte little-endian integer and return 0 on success and the value\r
- in *ret. Otherwise -1 is returned and *ret is not modified. */\r
-local int gz_next4(state, ret)\r
- gz_statep state;\r
- unsigned long *ret;\r
-{\r
- int ch;\r
- unsigned long val;\r
- z_streamp strm = &(state->strm);\r
-\r
- val = NEXT();\r
- val += (unsigned)NEXT() << 8;\r
- val += (unsigned long)NEXT() << 16;\r
- ch = NEXT();\r
- if (ch == -1)\r
- return -1;\r
- val += (unsigned long)ch << 24;\r
- *ret = val;\r
- return 0;\r
-}\r
-\r
-/* Look for gzip header, set up for inflate or copy. state->have must be zero.\r
- If this is the first time in, allocate required memory. state->how will be\r
- left unchanged if there is no more input data available, will be set to COPY\r
- if there is no gzip header and direct copying will be performed, or it will\r
- be set to GZIP for decompression, and the gzip header will be skipped so\r
- that the next available input data is the raw deflate stream. If direct\r
- copying, then leftover input data from the input buffer will be copied to\r
- the output buffer. In that case, all further file reads will be directly to\r
- either the output buffer or a user buffer. If decompressing, the inflate\r
- state and the check value will be initialized. gz_head() will return 0 on\r
- success or -1 on failure. Failures may include read errors or gzip header\r
- errors. */\r
-local int gz_head(state)\r
- gz_statep state;\r
-{\r
- z_streamp strm = &(state->strm);\r
- int flags;\r
- unsigned len;\r
-\r
- /* allocate read buffers and inflate memory */\r
- if (state->size == 0) {\r
- /* allocate buffers */\r
- state->in = malloc(state->want);\r
- state->out = malloc(state->want << 1);\r
- if (state->in == NULL || state->out == NULL) {\r
- if (state->out != NULL)\r
- free(state->out);\r
- if (state->in != NULL)\r
- free(state->in);\r
- gz_error(state, Z_MEM_ERROR, "out of memory");\r
- return -1;\r
- }\r
- state->size = state->want;\r
-\r
- /* allocate inflate memory */\r
- state->strm.zalloc = Z_NULL;\r
- state->strm.zfree = Z_NULL;\r
- state->strm.opaque = Z_NULL;\r
- state->strm.avail_in = 0;\r
- state->strm.next_in = Z_NULL;\r
- if (inflateInit2(&(state->strm), -15) != Z_OK) { /* raw inflate */\r
- free(state->out);\r
- free(state->in);\r
- state->size = 0;\r
- gz_error(state, Z_MEM_ERROR, "out of memory");\r
- return -1;\r
- }\r
- }\r
-\r
- /* get some data in the input buffer */\r
- if (strm->avail_in == 0) {\r
- if (gz_avail(state) == -1)\r
- return -1;\r
- if (strm->avail_in == 0)\r
- return 0;\r
- }\r
-\r
- /* look for the gzip magic header bytes 31 and 139 */\r
- if (strm->next_in[0] == 31) {\r
- strm->avail_in--;\r
- strm->next_in++;\r
- if (strm->avail_in == 0 && gz_avail(state) == -1)\r
- return -1;\r
- if (strm->avail_in && strm->next_in[0] == 139) {\r
- /* we have a gzip header, woo hoo! */\r
- strm->avail_in--;\r
- strm->next_in++;\r
-\r
- /* skip rest of header */\r
- if (NEXT() != 8) { /* compression method */\r
- gz_error(state, Z_DATA_ERROR, "unknown compression method");\r
- return -1;\r
- }\r
- flags = NEXT();\r
- if (flags & 0xe0) { /* reserved flag bits */\r
- gz_error(state, Z_DATA_ERROR, "unknown header flags set");\r
- return -1;\r
- }\r
- NEXT(); /* modification time */\r
- NEXT();\r
- NEXT();\r
- NEXT();\r
- NEXT(); /* extra flags */\r
- NEXT(); /* operating system */\r
- if (flags & 4) { /* extra field */\r
- len = (unsigned)NEXT();\r
- len += (unsigned)NEXT() << 8;\r
- while (len--)\r
- if (NEXT() < 0)\r
- break;\r
- }\r
- if (flags & 8) /* file name */\r
- while (NEXT() > 0)\r
- ;\r
- if (flags & 16) /* comment */\r
- while (NEXT() > 0)\r
- ;\r
- if (flags & 2) { /* header crc */\r
- NEXT();\r
- NEXT();\r
- }\r
- /* an unexpected end of file is not checked for here -- it will be\r
- noticed on the first request for uncompressed data */\r
-\r
- /* set up for decompression */\r
- inflateReset(strm);\r
- strm->adler = crc32(0L, Z_NULL, 0);\r
- state->how = GZIP;\r
- state->direct = 0;\r
- return 0;\r
- }\r
- else {\r
- /* not a gzip file -- save first byte (31) and fall to raw i/o */\r
- state->out[0] = 31;\r
- state->have = 1;\r
- }\r
- }\r
-\r
- /* doing raw i/o, save start of raw data for seeking, copy any leftover\r
- input to output -- this assumes that the output buffer is larger than\r
- the input buffer, which also assures space for gzungetc() */\r
- state->raw = state->pos;\r
- state->next = state->out;\r
- if (strm->avail_in) {\r
- memcpy(state->next + state->have, strm->next_in, strm->avail_in);\r
- state->have += strm->avail_in;\r
- strm->avail_in = 0;\r
- }\r
- state->how = COPY;\r
- state->direct = 1;\r
- return 0;\r
-}\r
-\r
-/* Decompress from input to the provided next_out and avail_out in the state.\r
- If the end of the compressed data is reached, then verify the gzip trailer\r
- check value and length (modulo 2^32). state->have and state->next are set\r
- to point to the just decompressed data, and the crc is updated. If the\r
- trailer is verified, state->how is reset to LOOK to look for the next gzip\r
- stream or raw data, once state->have is depleted. Returns 0 on success, -1\r
- on failure. Failures may include invalid compressed data or a failed gzip\r
- trailer verification. */\r
-local int gz_decomp(state)\r
- gz_statep state;\r
-{\r
- int ret;\r
- unsigned had;\r
- unsigned long crc, len;\r
- z_streamp strm = &(state->strm);\r
-\r
- /* fill output buffer up to end of deflate stream */\r
- had = strm->avail_out;\r
- do {\r
- /* get more input for inflate() */\r
- if (strm->avail_in == 0 && gz_avail(state) == -1)\r
- return -1;\r
- if (strm->avail_in == 0) {\r
- gz_error(state, Z_DATA_ERROR, "unexpected end of file");\r
- return -1;\r
- }\r
-\r
- /* decompress and handle errors */\r
- ret = inflate(strm, Z_NO_FLUSH);\r
- if (ret == Z_STREAM_ERROR || ret == Z_NEED_DICT) {\r
- gz_error(state, Z_STREAM_ERROR,\r
- "internal error: inflate stream corrupt");\r
- return -1;\r
- }\r
- if (ret == Z_MEM_ERROR) {\r
- gz_error(state, Z_MEM_ERROR, "out of memory");\r
- return -1;\r
- }\r
- if (ret == Z_DATA_ERROR) { /* deflate stream invalid */\r
- gz_error(state, Z_DATA_ERROR,\r
- strm->msg == NULL ? "compressed data error" : strm->msg);\r
- return -1;\r
- }\r
- } while (strm->avail_out && ret != Z_STREAM_END);\r
-\r
- /* update available output and crc check value */\r
- state->have = had - strm->avail_out;\r
- state->next = strm->next_out - state->have;\r
- strm->adler = crc32(strm->adler, state->next, state->have);\r
-\r
- /* check gzip trailer if at end of deflate stream */\r
- if (ret == Z_STREAM_END) {\r
- if (gz_next4(state, &crc) == -1 || gz_next4(state, &len) == -1) {\r
- gz_error(state, Z_DATA_ERROR, "unexpected end of file");\r
- return -1;\r
- }\r
- if (crc != strm->adler) {\r
- gz_error(state, Z_DATA_ERROR, "incorrect data check");\r
- return -1;\r
- }\r
- if (len != (strm->total_out & 0xffffffffL)) {\r
- gz_error(state, Z_DATA_ERROR, "incorrect length check");\r
- return -1;\r
- }\r
- state->how = LOOK; /* ready for next stream, once have is 0 (leave\r
- state->direct unchanged to remember how) */\r
- }\r
-\r
- /* good decompression */\r
- return 0;\r
-}\r
-\r
-/* Make data and put in the output buffer. Assumes that state->have == 0.\r
- Data is either copied from the input file or decompressed from the input\r
- file depending on state->how. If state->how is LOOK, then a gzip header is\r
- looked for (and skipped if found) to determine wither to copy or decompress.\r
- Returns -1 on error, otherwise 0. gz_make() will leave state->have as COPY\r
- or GZIP unless the end of the input file has been reached and all data has\r
- been processed. */\r
-local int gz_make(state)\r
- gz_statep state;\r
-{\r
- z_streamp strm = &(state->strm);\r
-\r
- if (state->how == LOOK) { /* look for gzip header */\r
- if (gz_head(state) == -1)\r
- return -1;\r
- if (state->have) /* got some data from gz_head() */\r
- return 0;\r
- }\r
- if (state->how == COPY) { /* straight copy */\r
- if (gz_load(state, state->out, state->size << 1, &(state->have)) == -1)\r
- return -1;\r
- state->next = state->out;\r
- }\r
- else if (state->how == GZIP) { /* decompress */\r
- strm->avail_out = state->size << 1;\r
- strm->next_out = state->out;\r
- if (gz_decomp(state) == -1)\r
- return -1;\r
- }\r
- return 0;\r
-}\r
-\r
-/* Skip len uncompressed bytes of output. Return -1 on error, 0 on success. */\r
-local int gz_skip(state, len)\r
- gz_statep state;\r
- z_off64_t len;\r
-{\r
- unsigned n;\r
-\r
- /* skip over len bytes or reach end-of-file, whichever comes first */\r
- while (len)\r
- /* skip over whatever is in output buffer */\r
- if (state->have) {\r
- n = GT_OFF(state->have) || (z_off64_t)state->have > len ?\r
- (unsigned)len : state->have;\r
- state->have -= n;\r
- state->next += n;\r
- state->pos += n;\r
- len -= n;\r
- }\r
-\r
- /* output buffer empty -- return if we're at the end of the input */\r
- else if (state->eof && state->strm.avail_in == 0)\r
- break;\r
-\r
- /* need more data to skip -- load up output buffer */\r
- else {\r
- /* get more output, looking for header if required */\r
- if (gz_make(state) == -1)\r
- return -1;\r
- }\r
- return 0;\r
-}\r
-\r
-/* -- see zlib.h -- */\r
-int ZEXPORT gzread(file, buf, len)\r
- gzFile file;\r
- voidp buf;\r
- unsigned len;\r
-{\r
- unsigned got, n;\r
- gz_statep state;\r
- z_streamp strm;\r
-\r
- /* get internal structure */\r
- if (file == NULL)\r
- return -1;\r
- state = (gz_statep)file;\r
- strm = &(state->strm);\r
-\r
- /* check that we're reading and that there's no error */\r
- if (state->mode != GZ_READ || state->err != Z_OK)\r
- return -1;\r
-\r
- /* since an int is returned, make sure len fits in one, otherwise return\r
- with an error (this avoids the flaw in the interface) */\r
- if ((int)len < 0) {\r
- gz_error(state, Z_BUF_ERROR, "requested length does not fit in int");\r
- return -1;\r
- }\r
-\r
- /* if len is zero, avoid unnecessary operations */\r
- if (len == 0)\r
- return 0;\r
-\r
- /* process a skip request */\r
- if (state->seek) {\r
- state->seek = 0;\r
- if (gz_skip(state, state->skip) == -1)\r
- return -1;\r
- }\r
-\r
- /* get len bytes to buf, or less than len if at the end */\r
- got = 0;\r
- do {\r
- /* first just try copying data from the output buffer */\r
- if (state->have) {\r
- n = state->have > len ? len : state->have;\r
- memcpy(buf, state->next, n);\r
- state->next += n;\r
- state->have -= n;\r
- }\r
-\r
- /* output buffer empty -- return if we're at the end of the input */\r
- else if (state->eof && strm->avail_in == 0)\r
- break;\r
-\r
- /* need output data -- for small len or new stream load up our output\r
- buffer */\r
- else if (state->how == LOOK || len < (state->size << 1)) {\r
- /* get more output, looking for header if required */\r
- if (gz_make(state) == -1)\r
- return -1;\r
- continue; /* no progress yet -- go back to memcpy() above */\r
- /* the copy above assures that we will leave with space in the\r
- output buffer, allowing at least one gzungetc() to succeed */\r
- }\r
-\r
- /* large len -- read directly into user buffer */\r
- else if (state->how == COPY) { /* read directly */\r
- if (gz_load(state, buf, len, &n) == -1)\r
- return -1;\r
- }\r
-\r
- /* large len -- decompress directly into user buffer */\r
- else { /* state->how == GZIP */\r
- strm->avail_out = len;\r
- strm->next_out = buf;\r
- if (gz_decomp(state) == -1)\r
- return -1;\r
- n = state->have;\r
- state->have = 0;\r
- }\r
-\r
- /* update progress */\r
- len -= n;\r
- buf = (char *)buf + n;\r
- got += n;\r
- state->pos += n;\r
- } while (len);\r
-\r
- /* return number of bytes read into user buffer (will fit in int) */\r
- return (int)got;\r
-}\r
-\r
-/* -- see zlib.h -- */\r
-int ZEXPORT gzgetc(file)\r
- gzFile file;\r
-{\r
- int ret;\r
- unsigned char buf[1];\r
- gz_statep state;\r
-\r
- /* get internal structure */\r
- if (file == NULL)\r
- return -1;\r
- state = (gz_statep)file;\r
-\r
- /* check that we're reading and that there's no error */\r
- if (state->mode != GZ_READ || state->err != Z_OK)\r
- return -1;\r
-\r
- /* try output buffer (no need to check for skip request) */\r
- if (state->have) {\r
- state->have--;\r
- state->pos++;\r
- return *(state->next)++;\r
- }\r
-\r
- /* nothing there -- try gzread() */\r
- ret = gzread(file, buf, 1);\r
- return ret < 1 ? -1 : buf[0];\r
-}\r
-\r
-/* -- see zlib.h -- */\r
-int ZEXPORT gzungetc(c, file)\r
- int c;\r
- gzFile file;\r
-{\r
- gz_statep state;\r
-\r
- /* get internal structure */\r
- if (file == NULL)\r
- return -1;\r
- state = (gz_statep)file;\r
-\r
- /* check that we're reading and that there's no error */\r
- if (state->mode != GZ_READ || state->err != Z_OK)\r
- return -1;\r
-\r
- /* process a skip request */\r
- if (state->seek) {\r
- state->seek = 0;\r
- if (gz_skip(state, state->skip) == -1)\r
- return -1;\r
- }\r
-\r
- /* can't push EOF */\r
- if (c < 0)\r
- return -1;\r
-\r
- /* if output buffer empty, put byte at end (allows more pushing) */\r
- if (state->have == 0) {\r
- state->have = 1;\r
- state->next = state->out + (state->size << 1) - 1;\r
- state->next[0] = c;\r
- state->pos--;\r
- return c;\r
- }\r
-\r
- /* if no room, give up (must have already done a gzungetc()) */\r
- if (state->have == (state->size << 1)) {\r
- gz_error(state, Z_BUF_ERROR, "out of room to push characters");\r
- return -1;\r
- }\r
-\r
- /* slide output data if needed and insert byte before existing data */\r
- if (state->next == state->out) {\r
- unsigned char *src = state->out + state->have;\r
- unsigned char *dest = state->out + (state->size << 1);\r
- while (src > state->out)\r
- *--dest = *--src;\r
- state->next = dest;\r
- }\r
- state->have++;\r
- state->next--;\r
- state->next[0] = c;\r
- state->pos--;\r
- return c;\r
-}\r
-\r
-/* -- see zlib.h -- */\r
-char * ZEXPORT gzgets(file, buf, len)\r
- gzFile file;\r
- char *buf;\r
- int len;\r
-{\r
- unsigned left, n;\r
- char *str;\r
- unsigned char *eol;\r
- gz_statep state;\r
-\r
- /* check parameters and get internal structure */\r
- if (file == NULL || buf == NULL || len < 1)\r
- return NULL;\r
- state = (gz_statep)file;\r
-\r
- /* check that we're reading and that there's no error */\r
- if (state->mode != GZ_READ || state->err != Z_OK)\r
- return NULL;\r
-\r
- /* process a skip request */\r
- if (state->seek) {\r
- state->seek = 0;\r
- if (gz_skip(state, state->skip) == -1)\r
- return NULL;\r
- }\r
-\r
- /* copy output bytes up to new line or len - 1, whichever comes first --\r
- append a terminating zero to the string (we don't check for a zero in\r
- the contents, let the user worry about that) */\r
- str = buf;\r
- left = (unsigned)len - 1;\r
- if (left) do {\r
- /* assure that something is in the output buffer */\r
- if (state->have == 0) {\r
- if (gz_make(state) == -1)\r
- return NULL; /* error */\r
- if (state->have == 0) { /* end of file */\r
- if (buf == str) /* got bupkus */\r
- return NULL;\r
- break; /* got something -- return it */\r
- }\r
- }\r
-\r
- /* look for end-of-line in current output buffer */\r
- n = state->have > left ? left : state->have;\r
- eol = memchr(state->next, '\n', n);\r
- if (eol != NULL)\r
- n = (unsigned)(eol - state->next) + 1;\r
-\r
- /* copy through end-of-line, or remainder if not found */\r
- memcpy(buf, state->next, n);\r
- state->have -= n;\r
- state->next += n;\r
- state->pos += n;\r
- left -= n;\r
- buf += n;\r
- } while (left && eol == NULL);\r
-\r
- /* found end-of-line or out of space -- terminate string and return it */\r
- buf[0] = 0;\r
- return str;\r
-}\r
-\r
-/* -- see zlib.h -- */\r
-int ZEXPORT gzdirect(file)\r
- gzFile file;\r
-{\r
- gz_statep state;\r
-\r
- /* get internal structure */\r
- if (file == NULL)\r
- return 0;\r
- state = (gz_statep)file;\r
-\r
- /* check that we're reading */\r
- if (state->mode != GZ_READ)\r
- return 0;\r
-\r
- /* if the state is not known, but we can find out, then do so (this is\r
- mainly for right after a gzopen() or gzdopen()) */\r
- if (state->how == LOOK && state->have == 0)\r
- (void)gz_head(state);\r
-\r
- /* return 1 if reading direct, 0 if decompressing a gzip stream */\r
- return state->direct;\r
-}\r
-\r
-/* -- see zlib.h -- */\r
-int ZEXPORT gzclose_r(file)\r
- gzFile file;\r
-{\r
- int ret;\r
- gz_statep state;\r
-\r
- /* get internal structure */\r
- if (file == NULL)\r
- return Z_STREAM_ERROR;\r
- state = (gz_statep)file;\r
-\r
- /* check that we're reading */\r
- if (state->mode != GZ_READ)\r
- return Z_STREAM_ERROR;\r
-\r
- /* free memory and close file */\r
- if (state->size) {\r
- inflateEnd(&(state->strm));\r
- free(state->out);\r
- free(state->in);\r
- }\r
- gz_error(state, Z_OK, NULL);\r
- free(state->path);\r
- ret = close(state->fd);\r
- free(state);\r
- return ret ? Z_ERRNO : Z_OK;\r
-}\r
+/* gzread.c -- zlib functions for reading gzip files
+ * Copyright (C) 2004, 2005, 2010, 2011, 2012 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, *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 = malloc(state->want);
+ state->out = malloc(state->want << 1);
+ if (state->in == NULL || state->out == NULL) {
+ if (state->out != NULL)
+ free(state->out);
+ if (state->in != NULL)
+ free(state->in);
+ gz_error(state, Z_MEM_ERROR, "out of memory");
+ return -1;
+ }
+ state->size = state->want;
+
+ /* allocate inflate memory */
+ state->strm.zalloc = Z_NULL;
+ state->strm.zfree = Z_NULL;
+ state->strm.opaque = Z_NULL;
+ state->strm.avail_in = 0;
+ state->strm.next_in = Z_NULL;
+ if (inflateInit2(&(state->strm), 15 + 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, buf, len, &n) == -1)
+ return -1;
+ }
+
+ /* large len -- decompress directly into user buffer */
+ else { /* state->how == GZIP */
+ strm->avail_out = len;
+ strm->next_out = buf;
+ if (gz_decomp(state) == -1)
+ return -1;
+ n = state->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 -- */
+#undef gzgetc
+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 = 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 / platform / upstream / libwebsockets.git / blobdiff