diff options
Diffstat (limited to 'lib/libz/gzio.c')
-rw-r--r-- | lib/libz/gzio.c | 399 |
1 files changed, 366 insertions, 33 deletions
diff --git a/lib/libz/gzio.c b/lib/libz/gzio.c index 6c82677..bd66085 100644 --- a/lib/libz/gzio.c +++ b/lib/libz/gzio.c @@ -1,9 +1,11 @@ /* gzio.c -- IO on .gz files - * Copyright (C) 1995-1996 Jean-loup Gailly. + * Copyright (C) 1995-1998 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: gzio.c,v 1.14 1996/07/24 13:41:01 me Exp $ */ +/* @(#) $Id$ */ #include <stdio.h> @@ -11,7 +13,8 @@ struct internal_state {int dummy;}; /* for buggy compilers */ -#define Z_BUFSIZE 4096 +#define Z_BUFSIZE 16384 +#define Z_PRINTF_BUFSIZE 4096 #define ALLOC(size) malloc(size) #define TRYFREE(p) {if (p) free(p);} @@ -38,10 +41,12 @@ typedef struct gz_stream { 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)); @@ -64,6 +69,7 @@ local gzFile gz_open (path, mode, 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 */ @@ -99,6 +105,10 @@ local gzFile gz_open (path, mode, fd) 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 */ } @@ -106,19 +116,24 @@ local gzFile gz_open (path, mode, fd) 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, 0); + 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 { - err = inflateInit2(&(s->stream), -MAX_WBITS); 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 */ + if (err != Z_OK || s->inbuf == Z_NULL) { return destroy(s), (gzFile)Z_NULL; } @@ -126,7 +141,7 @@ local gzFile gz_open (path, mode, fd) s->stream.avail_out = Z_BUFSIZE; errno = 0; - s->file = fd < 0 ? FOPEN(path, fmode) : (FILE*)fdopen(fd, fmode); + s->file = fd < 0 ? F_OPEN(path, fmode) : (FILE*)fdopen(fd, fmode); if (s->file == NULL) { return destroy(s), (gzFile)Z_NULL; @@ -136,16 +151,24 @@ local gzFile gz_open (path, mode, fd) */ 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 gzopen (path, mode) +gzFile ZEXPORT gzopen (path, mode) const char *path; const char *mode; { @@ -156,7 +179,7 @@ gzFile gzopen (path, mode) Associate a gzFile with the file descriptor fd. fd is not dup'ed here to mimic the behavio(u)r of fdopen. */ -gzFile gzdopen (fd, mode) +gzFile ZEXPORT gzdopen (fd, mode) int fd; const char *mode; { @@ -169,6 +192,31 @@ gzFile gzdopen (fd, mode) } /* =========================================================================== + * 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. @@ -212,8 +260,11 @@ local void check_header(s) for (len = 0; len < 2; len++) { c = get_byte(s); if (c != gz_magic[len]) { - s->transparent = 1; - if (c != EOF) s->stream.avail_in++, s->stream.next_in--; + 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; } @@ -260,14 +311,21 @@ local int destroy (s) TRYFREE(s->msg); if (s->stream.state != NULL) { - if (s->mode == 'w') { - err = deflateEnd(&(s->stream)); - } else if (s->mode == 'r') { - err = inflateEnd(&(s->stream)); - } + 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)) { - err = Z_ERRNO; +#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; @@ -282,13 +340,13 @@ local int destroy (s) 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 gzread (file, buf, len) +int ZEXPORT gzread (file, buf, len) gzFile file; voidp buf; unsigned len; { gz_stream *s = (gz_stream*)file; - Bytef *start = buf; /* starting point for crc computation */ + 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; @@ -296,7 +354,8 @@ int gzread (file, buf, len) if (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO) return -1; if (s->z_err == Z_STREAM_END) return 0; /* EOF */ - s->stream.next_out = next_out = buf; + next_out = (Byte*)buf; + s->stream.next_out = (Bytef*)buf; s->stream.avail_out = len; while (s->stream.avail_out != 0) { @@ -317,7 +376,10 @@ int gzread (file, buf, len) s->stream.avail_out -= fread(next_out, 1, s->stream.avail_out, s->file); } - return (int)(len - s->stream.avail_out); + len -= s->stream.avail_out; + s->stream.total_in += (uLong)len; + s->stream.total_out += (uLong)len; + return (int)len; } if (s->stream.avail_in == 0 && !s->z_eof) { @@ -345,7 +407,12 @@ int gzread (file, buf, len) /* Check for concatenated .gz 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); } } @@ -357,11 +424,49 @@ int gzread (file, buf, len) 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 gzwrite (file, buf, len) +int ZEXPORT gzwrite (file, buf, len) gzFile file; const voidp buf; unsigned len; @@ -370,7 +475,7 @@ int gzwrite (file, buf, len) if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR; - s->stream.next_in = buf; + s->stream.next_in = (Bytef*)buf; s->stream.avail_in = len; while (s->stream.avail_in != 0) { @@ -387,18 +492,95 @@ int gzwrite (file, buf, len) s->z_err = deflate(&(s->stream), Z_NO_FLUSH); if (s->z_err != Z_OK) break; } - s->crc = crc32(s->crc, buf, len); + 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, (const voidp)s, (unsigned)strlen(s)); +} + + +/* =========================================================================== Flushes all pending output into the compressed file. The parameter flush is as in the deflate() function. - gzflush should be called only when strictly necessary because it can - degrade compression. */ -int gzflush (file, flush) +local int do_flush (file, flush) gzFile file; int flush; { @@ -424,6 +606,9 @@ int gzflush (file, flush) 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: */ @@ -431,9 +616,154 @@ int gzflush (file, flush) 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_out; + } + 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; + + 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 @@ -470,7 +800,7 @@ local uLong getLong (s) Flushes all pending output if necessary, closes the compressed file and deallocates all the (de)compression state. */ -int gzclose (file) +int ZEXPORT gzclose (file) gzFile file; { int err; @@ -479,14 +809,17 @@ int gzclose (file) if (s == NULL) return Z_STREAM_ERROR; if (s->mode == 'w') { - err = gzflush (file, Z_FINISH); - if (err != Z_OK) return destroy(file); +#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(file); + return destroy((gz_stream*)file); } /* =========================================================================== @@ -496,7 +829,7 @@ int gzclose (file) errnum is set to Z_ERRNO and the application may consult errno to get the exact error code. */ -const char* gzerror (file, errnum) +const char* ZEXPORT gzerror (file, errnum) gzFile file; int *errnum; { |