+++ /dev/null
-/* gzio.c -- IO on .gz files
- * Copyright (C) 1995-2002 Jean-loup Gailly.
- * For conditions of distribution and use, see copyright notice in zlib.h
- *
- * Compile this file with -DNO_DEFLATE to avoid the compression code.
- */
-
-/* @(#) $Id$ */
-
-#include <stdio.h>
-
-#include "zutil.h"
-
-struct internal_state {int dummy;}; /* for buggy compilers */
-
-#ifndef Z_BUFSIZE
-# ifdef MAXSEG_64K
-# define Z_BUFSIZE 4096 /* minimize memory usage for 16-bit DOS */
-# else
-# define Z_BUFSIZE 16384
-# endif
-#endif
-#ifndef Z_PRINTF_BUFSIZE
-# define Z_PRINTF_BUFSIZE 4096
-#endif
-
-#define ALLOC(size) malloc(size)
-#define TRYFREE(p) {if (p) free(p);}
-
-static int gz_magic[2] = {0x1f, 0x8b}; /* gzip magic header */
-
-/* gzip flag byte */
-#define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */
-#define HEAD_CRC 0x02 /* bit 1 set: header CRC present */
-#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
-#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
-#define COMMENT 0x10 /* bit 4 set: file comment present */
-#define RESERVED 0xE0 /* bits 5..7: reserved */
-
-typedef struct gz_stream {
- z_stream stream;
- int z_err; /* error code for last stream operation */
- int z_eof; /* set if end of input file */
- FILE *file; /* .gz file */
- Byte *inbuf; /* input buffer */
- Byte *outbuf; /* output buffer */
- uLong crc; /* crc32 of uncompressed data */
- char *msg; /* error message */
- char *path; /* path name for debugging only */
- int transparent; /* 1 if input file is not a .gz file */
- char mode; /* 'w' or 'r' */
- long startpos; /* start of compressed data in file (header skipped) */
-} gz_stream;
-
-
-local gzFile gz_open OF((const char *path, const char *mode, int fd));
-local int do_flush OF((gzFile file, int flush));
-local int get_byte OF((gz_stream *s));
-local void check_header OF((gz_stream *s));
-local int destroy OF((gz_stream *s));
-local void putLong OF((FILE *file, uLong x));
-local uLong getLong OF((gz_stream *s));
-
-/* ===========================================================================
- Opens a gzip (.gz) file for reading or writing. The mode parameter
- is as in fopen ("rb" or "wb"). The file is given either by file descriptor
- or path name (if fd == -1).
- gz_open return NULL if the file could not be opened or if there was
- insufficient memory to allocate the (de)compression state; errno
- can be checked to distinguish the two cases (if errno is zero, the
- zlib error is Z_MEM_ERROR).
-*/
-local gzFile gz_open (path, mode, fd)
- const char *path;
- const char *mode;
- int fd;
-{
- int err;
- int level = Z_DEFAULT_COMPRESSION; /* compression level */
- int strategy = Z_DEFAULT_STRATEGY; /* compression strategy */
- char *p = (char*)mode;
- gz_stream *s;
- char fmode[80]; /* copy of mode, without the compression level */
- char *m = fmode;
-
- if (!path || !mode) return Z_NULL;
-
- s = (gz_stream *)ALLOC(sizeof(gz_stream));
- if (!s) return Z_NULL;
-
- s->stream.zalloc = (alloc_func)0;
- s->stream.zfree = (free_func)0;
- s->stream.opaque = (voidpf)0;
- s->stream.next_in = s->inbuf = Z_NULL;
- s->stream.next_out = s->outbuf = Z_NULL;
- s->stream.avail_in = s->stream.avail_out = 0;
- s->file = NULL;
- s->z_err = Z_OK;
- s->z_eof = 0;
- s->crc = crc32(0L, Z_NULL, 0);
- s->msg = NULL;
- s->transparent = 0;
-
- s->path = (char*)ALLOC(strlen(path)+1);
- if (s->path == NULL) {
- return destroy(s), (gzFile)Z_NULL;
- }
- strcpy(s->path, path); /* do this early for debugging */
-
- s->mode = '\0';
- do {
- if (*p == 'r') s->mode = 'r';
- if (*p == 'w' || *p == 'a') s->mode = 'w';
- if (*p >= '0' && *p <= '9') {
- level = *p - '0';
- } else if (*p == 'f') {
- strategy = Z_FILTERED;
- } else if (*p == 'h') {
- strategy = Z_HUFFMAN_ONLY;
- } else {
- *m++ = *p; /* copy the mode */
- }
- } while (*p++ && m != fmode + sizeof(fmode));
- if (s->mode == '\0') return destroy(s), (gzFile)Z_NULL;
-
- if (s->mode == 'w') {
-#ifdef NO_DEFLATE
- err = Z_STREAM_ERROR;
-#else
- err = deflateInit2(&(s->stream), level,
- Z_DEFLATED, -MAX_WBITS, DEF_MEM_LEVEL, strategy);
- /* windowBits is passed < 0 to suppress zlib header */
-
- s->stream.next_out = s->outbuf = (Byte*)ALLOC(Z_BUFSIZE);
-#endif
- if (err != Z_OK || s->outbuf == Z_NULL) {
- return destroy(s), (gzFile)Z_NULL;
- }
- } else {
- s->stream.next_in = s->inbuf = (Byte*)ALLOC(Z_BUFSIZE);
-
- err = inflateInit2(&(s->stream), -MAX_WBITS);
- /* windowBits is passed < 0 to tell that there is no zlib header.
- * Note that in this case inflate *requires* an extra "dummy" byte
- * after the compressed stream in order to complete decompression and
- * return Z_STREAM_END. Here the gzip CRC32 ensures that 4 bytes are
- * present after the compressed stream.
- */
- if (err != Z_OK || s->inbuf == Z_NULL) {
- return destroy(s), (gzFile)Z_NULL;
- }
- }
- s->stream.avail_out = Z_BUFSIZE;
-
- errno = 0;
- s->file = fd < 0 ? F_OPEN(path, fmode) : (FILE*)fdopen(fd, fmode);
-
- if (s->file == NULL) {
- return destroy(s), (gzFile)Z_NULL;
- }
- if (s->mode == 'w') {
- /* Write a very simple .gz header:
- */
- fprintf(s->file, "%c%c%c%c%c%c%c%c%c%c", gz_magic[0], gz_magic[1],
- Z_DEFLATED, 0 /*flags*/, 0,0,0,0 /*time*/, 0 /*xflags*/, OS_CODE);
- s->startpos = 10L;
- /* We use 10L instead of ftell(s->file) to because ftell causes an
- * fflush on some systems. This version of the library doesn't use
- * startpos anyway in write mode, so this initialization is not
- * necessary.
- */
- } else {
- check_header(s); /* skip the .gz header */
- s->startpos = (ftell(s->file) - s->stream.avail_in);
- }
-
- return (gzFile)s;
-}
-
-/* ===========================================================================
- Opens a gzip (.gz) file for reading or writing.
-*/
-gzFile ZEXPORT gzopen (path, mode)
- const char *path;
- const char *mode;
-{
- return gz_open (path, mode, -1);
-}
-
-/* ===========================================================================
- Associate a gzFile with the file descriptor fd. fd is not dup'ed here
- to mimic the behavio(u)r of fdopen.
-*/
-gzFile ZEXPORT gzdopen (fd, mode)
- int fd;
- const char *mode;
-{
- char name[20];
-
- if (fd < 0) return (gzFile)Z_NULL;
- sprintf(name, "<fd:%d>", fd); /* for debugging */
-
- return gz_open (name, mode, fd);
-}
-
-/* ===========================================================================
- * Update the compression level and strategy
- */
-int ZEXPORT gzsetparams (file, level, strategy)
- gzFile file;
- int level;
- int strategy;
-{
- gz_stream *s = (gz_stream*)file;
-
- if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR;
-
- /* Make room to allow flushing */
- if (s->stream.avail_out == 0) {
-
- s->stream.next_out = s->outbuf;
- if (fwrite(s->outbuf, 1, Z_BUFSIZE, s->file) != Z_BUFSIZE) {
- s->z_err = Z_ERRNO;
- }
- s->stream.avail_out = Z_BUFSIZE;
- }
-
- return deflateParams (&(s->stream), level, strategy);
-}
-
-/* ===========================================================================
- Read a byte from a gz_stream; update next_in and avail_in. Return EOF
- for end of file.
- IN assertion: the stream s has been sucessfully opened for reading.
-*/
-local int get_byte(s)
- gz_stream *s;
-{
- if (s->z_eof) return EOF;
- if (s->stream.avail_in == 0) {
- errno = 0;
- s->stream.avail_in = fread(s->inbuf, 1, Z_BUFSIZE, s->file);
- if (s->stream.avail_in == 0) {
- s->z_eof = 1;
- if (ferror(s->file)) s->z_err = Z_ERRNO;
- return EOF;
- }
- s->stream.next_in = s->inbuf;
- }
- s->stream.avail_in--;
- return *(s->stream.next_in)++;
-}
-
-/* ===========================================================================
- Check the gzip header of a gz_stream opened for reading. Set the stream
- mode to transparent if the gzip magic header is not present; set s->err
- to Z_DATA_ERROR if the magic header is present but the rest of the header
- is incorrect.
- IN assertion: the stream s has already been created sucessfully;
- s->stream.avail_in is zero for the first time, but may be non-zero
- for concatenated .gz files.
-*/
-local void check_header(s)
- gz_stream *s;
-{
- int method; /* method byte */
- int flags; /* flags byte */
- uInt len;
- int c;
-
- /* Check the gzip magic header */
- for (len = 0; len < 2; len++) {
- c = get_byte(s);
- if (c != gz_magic[len]) {
- if (len != 0) s->stream.avail_in++, s->stream.next_in--;
- if (c != EOF) {
- s->stream.avail_in++, s->stream.next_in--;
- s->transparent = 1;
- }
- s->z_err = s->stream.avail_in != 0 ? Z_OK : Z_STREAM_END;
- return;
- }
- }
- method = get_byte(s);
- flags = get_byte(s);
- if (method != Z_DEFLATED || (flags & RESERVED) != 0) {
- s->z_err = Z_DATA_ERROR;
- return;
- }
-
- /* Discard time, xflags and OS code: */
- for (len = 0; len < 6; len++) (void)get_byte(s);
-
- if ((flags & EXTRA_FIELD) != 0) { /* skip the extra field */
- len = (uInt)get_byte(s);
- len += ((uInt)get_byte(s))<<8;
- /* len is garbage if EOF but the loop below will quit anyway */
- while (len-- != 0 && get_byte(s) != EOF) ;
- }
- if ((flags & ORIG_NAME) != 0) { /* skip the original file name */
- while ((c = get_byte(s)) != 0 && c != EOF) ;
- }
- if ((flags & COMMENT) != 0) { /* skip the .gz file comment */
- while ((c = get_byte(s)) != 0 && c != EOF) ;
- }
- if ((flags & HEAD_CRC) != 0) { /* skip the header crc */
- for (len = 0; len < 2; len++) (void)get_byte(s);
- }
- s->z_err = s->z_eof ? Z_DATA_ERROR : Z_OK;
-}
-
- /* ===========================================================================
- * Cleanup then free the given gz_stream. Return a zlib error code.
- Try freeing in the reverse order of allocations.
- */
-local int destroy (s)
- gz_stream *s;
-{
- int err = Z_OK;
-
- if (!s) return Z_STREAM_ERROR;
-
- TRYFREE(s->msg);
-
- if (s->stream.state != NULL) {
- if (s->mode == 'w') {
-#ifdef NO_DEFLATE
- err = Z_STREAM_ERROR;
-#else
- err = deflateEnd(&(s->stream));
-#endif
- } else if (s->mode == 'r') {
- err = inflateEnd(&(s->stream));
- }
- }
- if (s->file != NULL && fclose(s->file)) {
-#ifdef ESPIPE
- if (errno != ESPIPE) /* fclose is broken for pipes in HP/UX */
-#endif
- err = Z_ERRNO;
- }
- if (s->z_err < 0) err = s->z_err;
-
- TRYFREE(s->inbuf);
- TRYFREE(s->outbuf);
- TRYFREE(s->path);
- TRYFREE(s);
- return err;
-}
-
-/* ===========================================================================
- Reads the given number of uncompressed bytes from the compressed file.
- gzread returns the number of bytes actually read (0 for end of file).
-*/
-int ZEXPORT gzread (file, buf, len)
- gzFile file;
- voidp buf;
- unsigned len;
-{
- gz_stream *s = (gz_stream*)file;
- Bytef *start = (Bytef*)buf; /* starting point for crc computation */
- Byte *next_out; /* == stream.next_out but not forced far (for MSDOS) */
-
- if (s == NULL || s->mode != 'r') return Z_STREAM_ERROR;
-
- if (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO) return -1;
- if (s->z_err == Z_STREAM_END) return 0; /* EOF */
-
- next_out = (Byte*)buf;
- s->stream.next_out = (Bytef*)buf;
- s->stream.avail_out = len;
-
- while (s->stream.avail_out != 0) {
-
- if (s->transparent) {
- /* Copy first the lookahead bytes: */
- uInt n = s->stream.avail_in;
- if (n > s->stream.avail_out) n = s->stream.avail_out;
- if (n > 0) {
- zmemcpy(s->stream.next_out, s->stream.next_in, n);
- next_out += n;
- s->stream.next_out = next_out;
- s->stream.next_in += n;
- s->stream.avail_out -= n;
- s->stream.avail_in -= n;
- }
- if (s->stream.avail_out > 0) {
- s->stream.avail_out -= fread(next_out, 1, s->stream.avail_out,
- s->file);
- }
- len -= s->stream.avail_out;
- s->stream.total_in += (uLong)len;
- s->stream.total_out += (uLong)len;
- if (len == 0) s->z_eof = 1;
- return (int)len;
- }
- if (s->stream.avail_in == 0 && !s->z_eof) {
-
- errno = 0;
- s->stream.avail_in = fread(s->inbuf, 1, Z_BUFSIZE, s->file);
- if (s->stream.avail_in == 0) {
- s->z_eof = 1;
- if (ferror(s->file)) {
- s->z_err = Z_ERRNO;
- break;
- }
- }
- s->stream.next_in = s->inbuf;
- }
- s->z_err = inflate(&(s->stream), Z_NO_FLUSH);
-
- if (s->z_err == Z_STREAM_END) {
- /* Check CRC and original size */
- s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start));
- start = s->stream.next_out;
-
- if (getLong(s) != s->crc) {
- s->z_err = Z_DATA_ERROR;
- } else {
- (void)getLong(s);
- /* The uncompressed length returned by above getlong() may
- * be different from s->stream.total_out) in case of
- * concatenated .gz files. Check for such files:
- */
- check_header(s);
- if (s->z_err == Z_OK) {
- uLong total_in = s->stream.total_in;
- uLong total_out = s->stream.total_out;
-
- inflateReset(&(s->stream));
- s->stream.total_in = total_in;
- s->stream.total_out = total_out;
- s->crc = crc32(0L, Z_NULL, 0);
- }
- }
- }
- if (s->z_err != Z_OK || s->z_eof) break;
- }
- s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start));
-
- return (int)(len - s->stream.avail_out);
-}
-
-
-/* ===========================================================================
- Reads one byte from the compressed file. gzgetc returns this byte
- or -1 in case of end of file or error.
-*/
-int ZEXPORT gzgetc(file)
- gzFile file;
-{
- unsigned char c;
-
- return gzread(file, &c, 1) == 1 ? c : -1;
-}
-
-
-/* ===========================================================================
- Reads bytes from the compressed file until len-1 characters are
- read, or a newline character is read and transferred to buf, or an
- end-of-file condition is encountered. The string is then terminated
- with a null character.
- gzgets returns buf, or Z_NULL in case of error.
-
- The current implementation is not optimized at all.
-*/
-char * ZEXPORT gzgets(file, buf, len)
- gzFile file;
- char *buf;
- int len;
-{
- char *b = buf;
- if (buf == Z_NULL || len <= 0) return Z_NULL;
-
- while (--len > 0 && gzread(file, buf, 1) == 1 && *buf++ != '\n') ;
- *buf = '\0';
- return b == buf && len > 0 ? Z_NULL : b;
-}
-
-
-#ifndef NO_DEFLATE
-/* ===========================================================================
- Writes the given number of uncompressed bytes into the compressed file.
- gzwrite returns the number of bytes actually written (0 in case of error).
-*/
-int ZEXPORT gzwrite (file, buf, len)
- gzFile file;
- const voidp buf;
- unsigned len;
-{
- gz_stream *s = (gz_stream*)file;
-
- if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR;
-
- s->stream.next_in = (Bytef*)buf;
- s->stream.avail_in = len;
-
- while (s->stream.avail_in != 0) {
-
- if (s->stream.avail_out == 0) {
-
- s->stream.next_out = s->outbuf;
- if (fwrite(s->outbuf, 1, Z_BUFSIZE, s->file) != Z_BUFSIZE) {
- s->z_err = Z_ERRNO;
- break;
- }
- s->stream.avail_out = Z_BUFSIZE;
- }
- s->z_err = deflate(&(s->stream), Z_NO_FLUSH);
- if (s->z_err != Z_OK) break;
- }
- s->crc = crc32(s->crc, (const Bytef *)buf, len);
-
- return (int)(len - s->stream.avail_in);
-}
-
-/* ===========================================================================
- Converts, formats, and writes the args to the compressed file under
- control of the format string, as in fprintf. gzprintf returns the number of
- uncompressed bytes actually written (0 in case of error).
-*/
-#ifdef STDC
-#include <stdarg.h>
-
-int ZEXPORTVA gzprintf (gzFile file, const char *format, /* args */ ...)
-{
- char buf[Z_PRINTF_BUFSIZE];
- va_list va;
- int len;
-
- va_start(va, format);
-#ifdef HAS_vsnprintf
- (void)vsnprintf(buf, sizeof(buf), format, va);
-#else
- (void)vsprintf(buf, format, va);
-#endif
- va_end(va);
- len = strlen(buf); /* some *sprintf don't return the nb of bytes written */
- if (len <= 0) return 0;
-
- return gzwrite(file, buf, (unsigned)len);
-}
-#else /* not ANSI C */
-
-int ZEXPORTVA gzprintf (file, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
- a11, a12, a13, a14, a15, a16, a17, a18, a19, a20)
- gzFile file;
- const char *format;
- int a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
- a11, a12, a13, a14, a15, a16, a17, a18, a19, a20;
-{
- char buf[Z_PRINTF_BUFSIZE];
- int len;
-
-#ifdef HAS_snprintf
- snprintf(buf, sizeof(buf), format, a1, a2, a3, a4, a5, a6, a7, a8,
- a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
-#else
- sprintf(buf, format, a1, a2, a3, a4, a5, a6, a7, a8,
- a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
-#endif
- len = strlen(buf); /* old sprintf doesn't return the nb of bytes written */
- if (len <= 0) return 0;
-
- return gzwrite(file, buf, len);
-}
-#endif
-
-/* ===========================================================================
- Writes c, converted to an unsigned char, into the compressed file.
- gzputc returns the value that was written, or -1 in case of error.
-*/
-int ZEXPORT gzputc(file, c)
- gzFile file;
- int c;
-{
- unsigned char cc = (unsigned char) c; /* required for big endian systems */
-
- return gzwrite(file, &cc, 1) == 1 ? (int)cc : -1;
-}
-
-
-/* ===========================================================================
- Writes the given null-terminated string to the compressed file, excluding
- the terminating null character.
- gzputs returns the number of characters written, or -1 in case of error.
-*/
-int ZEXPORT gzputs(file, s)
- gzFile file;
- const char *s;
-{
- return gzwrite(file, (char*)s, (unsigned)strlen(s));
-}
-
-
-/* ===========================================================================
- Flushes all pending output into the compressed file. The parameter
- flush is as in the deflate() function.
-*/
-local int do_flush (file, flush)
- gzFile file;
- int flush;
-{
- uInt len;
- int done = 0;
- gz_stream *s = (gz_stream*)file;
-
- if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR;
-
- s->stream.avail_in = 0; /* should be zero already anyway */
-
- for (;;) {
- len = Z_BUFSIZE - s->stream.avail_out;
-
- if (len != 0) {
- if ((uInt)fwrite(s->outbuf, 1, len, s->file) != len) {
- s->z_err = Z_ERRNO;
- return Z_ERRNO;
- }
- s->stream.next_out = s->outbuf;
- s->stream.avail_out = Z_BUFSIZE;
- }
- if (done) break;
- s->z_err = deflate(&(s->stream), flush);
-
- /* Ignore the second of two consecutive flushes: */
- if (len == 0 && s->z_err == Z_BUF_ERROR) s->z_err = Z_OK;
-
- /* deflate has finished flushing only when it hasn't used up
- * all the available space in the output buffer:
- */
- done = (s->stream.avail_out != 0 || s->z_err == Z_STREAM_END);
-
- if (s->z_err != Z_OK && s->z_err != Z_STREAM_END) break;
- }
- return s->z_err == Z_STREAM_END ? Z_OK : s->z_err;
-}
-
-int ZEXPORT gzflush (file, flush)
- gzFile file;
- int flush;
-{
- gz_stream *s = (gz_stream*)file;
- int err = do_flush (file, flush);
-
- if (err) return err;
- fflush(s->file);
- return s->z_err == Z_STREAM_END ? Z_OK : s->z_err;
-}
-#endif /* NO_DEFLATE */
-
-/* ===========================================================================
- Sets the starting position for the next gzread or gzwrite on the given
- compressed file. The offset represents a number of bytes in the
- gzseek returns the resulting offset location as measured in bytes from
- the beginning of the uncompressed stream, or -1 in case of error.
- SEEK_END is not implemented, returns error.
- In this version of the library, gzseek can be extremely slow.
-*/
-z_off_t ZEXPORT gzseek (file, offset, whence)
- gzFile file;
- z_off_t offset;
- int whence;
-{
- gz_stream *s = (gz_stream*)file;
-
- if (s == NULL || whence == SEEK_END ||
- s->z_err == Z_ERRNO || s->z_err == Z_DATA_ERROR) {
- return -1L;
- }
-
- if (s->mode == 'w') {
-#ifdef NO_DEFLATE
- return -1L;
-#else
- if (whence == SEEK_SET) {
- offset -= s->stream.total_in;
- }
- if (offset < 0) return -1L;
-
- /* At this point, offset is the number of zero bytes to write. */
- if (s->inbuf == Z_NULL) {
- s->inbuf = (Byte*)ALLOC(Z_BUFSIZE); /* for seeking */
- zmemzero(s->inbuf, Z_BUFSIZE);
- }
- while (offset > 0) {
- uInt size = Z_BUFSIZE;
- if (offset < Z_BUFSIZE) size = (uInt)offset;
-
- size = gzwrite(file, s->inbuf, size);
- if (size == 0) return -1L;
-
- offset -= size;
- }
- return (z_off_t)s->stream.total_in;
-#endif
- }
- /* Rest of function is for reading only */
-
- /* compute absolute position */
- if (whence == SEEK_CUR) {
- offset += s->stream.total_out;
- }
- if (offset < 0) return -1L;
-
- if (s->transparent) {
- /* map to fseek */
- s->stream.avail_in = 0;
- s->stream.next_in = s->inbuf;
- if (fseek(s->file, offset, SEEK_SET) < 0) return -1L;
-
- s->stream.total_in = s->stream.total_out = (uLong)offset;
- return offset;
- }
-
- /* For a negative seek, rewind and use positive seek */
- if ((uLong)offset >= s->stream.total_out) {
- offset -= s->stream.total_out;
- } else if (gzrewind(file) < 0) {
- return -1L;
- }
- /* offset is now the number of bytes to skip. */
-
- if (offset != 0 && s->outbuf == Z_NULL) {
- s->outbuf = (Byte*)ALLOC(Z_BUFSIZE);
- }
- while (offset > 0) {
- int size = Z_BUFSIZE;
- if (offset < Z_BUFSIZE) size = (int)offset;
-
- size = gzread(file, s->outbuf, (uInt)size);
- if (size <= 0) return -1L;
- offset -= size;
- }
- return (z_off_t)s->stream.total_out;
-}
-
-/* ===========================================================================
- Rewinds input file.
-*/
-int ZEXPORT gzrewind (file)
- gzFile file;
-{
- gz_stream *s = (gz_stream*)file;
-
- if (s == NULL || s->mode != 'r') return -1;
-
- s->z_err = Z_OK;
- s->z_eof = 0;
- s->stream.avail_in = 0;
- s->stream.next_in = s->inbuf;
- s->crc = crc32(0L, Z_NULL, 0);
-
- if (s->startpos == 0) { /* not a compressed file */
- rewind(s->file);
- return 0;
- }
-
- (void) inflateReset(&s->stream);
- return fseek(s->file, s->startpos, SEEK_SET);
-}
-
-/* ===========================================================================
- Returns the starting position for the next gzread or gzwrite on the
- given compressed file. This position represents a number of bytes in the
- uncompressed data stream.
-*/
-z_off_t ZEXPORT gztell (file)
- gzFile file;
-{
- return gzseek(file, 0L, SEEK_CUR);
-}
-
-/* ===========================================================================
- Returns 1 when EOF has previously been detected reading the given
- input stream, otherwise zero.
-*/
-int ZEXPORT gzeof (file)
- gzFile file;
-{
- gz_stream *s = (gz_stream*)file;
-
- return (s == NULL || s->mode != 'r') ? 0 : s->z_eof;
-}
-
-/* ===========================================================================
- Outputs a long in LSB order to the given file
-*/
-local void putLong (file, x)
- FILE *file;
- uLong x;
-{
- int n;
- for (n = 0; n < 4; n++) {
- fputc((int)(x & 0xff), file);
- x >>= 8;
- }
-}
-
-/* ===========================================================================
- Reads a long in LSB order from the given gz_stream. Sets z_err in case
- of error.
-*/
-local uLong getLong (s)
- gz_stream *s;
-{
- uLong x = (uLong)get_byte(s);
- int c;
-
- x += ((uLong)get_byte(s))<<8;
- x += ((uLong)get_byte(s))<<16;
- c = get_byte(s);
- if (c == EOF) s->z_err = Z_DATA_ERROR;
- x += ((uLong)c)<<24;
- return x;
-}
-
-/* ===========================================================================
- Flushes all pending output if necessary, closes the compressed file
- and deallocates all the (de)compression state.
-*/
-int ZEXPORT gzclose (file)
- gzFile file;
-{
- int err;
- gz_stream *s = (gz_stream*)file;
-
- if (s == NULL) return Z_STREAM_ERROR;
-
- if (s->mode == 'w') {
-#ifdef NO_DEFLATE
- return Z_STREAM_ERROR;
-#else
- err = do_flush (file, Z_FINISH);
- if (err != Z_OK) return destroy((gz_stream*)file);
-
- putLong (s->file, s->crc);
- putLong (s->file, s->stream.total_in);
-#endif
- }
- return destroy((gz_stream*)file);
-}
-
-/* ===========================================================================
- Returns the error message for the last error which occured on the
- given compressed file. errnum is set to zlib error number. If an
- error occured in the file system and not in the compression library,
- errnum is set to Z_ERRNO and the application may consult errno
- to get the exact error code.
-*/
-const char* ZEXPORT gzerror (file, errnum)
- gzFile file;
- int *errnum;
-{
- char *m;
- gz_stream *s = (gz_stream*)file;
-
- if (s == NULL) {
- *errnum = Z_STREAM_ERROR;
- return (const char*)ERR_MSG(Z_STREAM_ERROR);
- }
- *errnum = s->z_err;
- if (*errnum == Z_OK) return (const char*)"";
-
- m = (char*)(*errnum == Z_ERRNO ? zstrerror(errno) : s->stream.msg);
-
- if (m == NULL || *m == '\0') m = (char*)ERR_MSG(s->z_err);
-
- TRYFREE(s->msg);
- s->msg = (char*)ALLOC(strlen(s->path) + strlen(m) + 3);
- strcpy(s->msg, s->path);
- strcat(s->msg, ": ");
- strcat(s->msg, m);
- return (const char*)s->msg;
-}
projects / rrdtool.git / blobdiff