From b40c451c061d0e5bfd030d12556b5ac2d702064f Mon Sep 17 00:00:00 2001 From: cvs2git Date: Fri, 18 Mar 2011 10:11:30 +0000 Subject: This commit was manufactured by cvs2svn to create branch 'zlib'. Cherrypick from master 2011-03-18 10:11:29 UTC Joel Sherrill '2010-03-22 Joel Sherrill ': cpukit/zlib/doc/algorithm.txt cpukit/zlib/gzclose.c cpukit/zlib/gzguts.h cpukit/zlib/gzlib.c cpukit/zlib/gzread.c cpukit/zlib/gzwrite.c --- cpukit/zlib/doc/algorithm.txt | 209 ++++++++++++++ cpukit/zlib/gzclose.c | 25 ++ cpukit/zlib/gzguts.h | 132 +++++++++ cpukit/zlib/gzlib.c | 535 ++++++++++++++++++++++++++++++++++ cpukit/zlib/gzread.c | 652 ++++++++++++++++++++++++++++++++++++++++++ cpukit/zlib/gzwrite.c | 531 ++++++++++++++++++++++++++++++++++ 6 files changed, 2084 insertions(+) create mode 100644 cpukit/zlib/doc/algorithm.txt create mode 100644 cpukit/zlib/gzclose.c create mode 100644 cpukit/zlib/gzguts.h create mode 100644 cpukit/zlib/gzlib.c create mode 100644 cpukit/zlib/gzread.c create mode 100644 cpukit/zlib/gzwrite.c (limited to 'cpukit') diff --git a/cpukit/zlib/doc/algorithm.txt b/cpukit/zlib/doc/algorithm.txt new file mode 100644 index 0000000000..34960bddac --- /dev/null +++ b/cpukit/zlib/doc/algorithm.txt @@ -0,0 +1,209 @@ +1. Compression algorithm (deflate) + +The deflation algorithm used by gzip (also zip and zlib) is a variation of +LZ77 (Lempel-Ziv 1977, see reference below). It finds duplicated strings in +the input data. The second occurrence of a string is replaced by a +pointer to the previous string, in the form of a pair (distance, +length). Distances are limited to 32K bytes, and lengths are limited +to 258 bytes. When a string does not occur anywhere in the previous +32K bytes, it is emitted as a sequence of literal bytes. (In this +description, `string' must be taken as an arbitrary sequence of bytes, +and is not restricted to printable characters.) + +Literals or match lengths are compressed with one Huffman tree, and +match distances are compressed with another tree. The trees are stored +in a compact form at the start of each block. The blocks can have any +size (except that the compressed data for one block must fit in +available memory). A block is terminated when deflate() determines that +it would be useful to start another block with fresh trees. (This is +somewhat similar to the behavior of LZW-based _compress_.) + +Duplicated strings are found using a hash table. All input strings of +length 3 are inserted in the hash table. A hash index is computed for +the next 3 bytes. If the hash chain for this index is not empty, all +strings in the chain are compared with the current input string, and +the longest match is selected. + +The hash chains are searched starting with the most recent strings, to +favor small distances and thus take advantage of the Huffman encoding. +The hash chains are singly linked. There are no deletions from the +hash chains, the algorithm simply discards matches that are too old. + +To avoid a worst-case situation, very long hash chains are arbitrarily +truncated at a certain length, determined by a runtime option (level +parameter of deflateInit). So deflate() does not always find the longest +possible match but generally finds a match which is long enough. + +deflate() also defers the selection of matches with a lazy evaluation +mechanism. After a match of length N has been found, deflate() searches for +a longer match at the next input byte. If a longer match is found, the +previous match is truncated to a length of one (thus producing a single +literal byte) and the process of lazy evaluation begins again. Otherwise, +the original match is kept, and the next match search is attempted only N +steps later. + +The lazy match evaluation is also subject to a runtime parameter. If +the current match is long enough, deflate() reduces the search for a longer +match, thus speeding up the whole process. If compression ratio is more +important than speed, deflate() attempts a complete second search even if +the first match is already long enough. + +The lazy match evaluation is not performed for the fastest compression +modes (level parameter 1 to 3). For these fast modes, new strings +are inserted in the hash table only when no match was found, or +when the match is not too long. This degrades the compression ratio +but saves time since there are both fewer insertions and fewer searches. + + +2. Decompression algorithm (inflate) + +2.1 Introduction + +The key question is how to represent a Huffman code (or any prefix code) so +that you can decode fast. The most important characteristic is that shorter +codes are much more common than longer codes, so pay attention to decoding the +short codes fast, and let the long codes take longer to decode. + +inflate() sets up a first level table that covers some number of bits of +input less than the length of longest code. It gets that many bits from the +stream, and looks it up in the table. The table will tell if the next +code is that many bits or less and how many, and if it is, it will tell +the value, else it will point to the next level table for which inflate() +grabs more bits and tries to decode a longer code. + +How many bits to make the first lookup is a tradeoff between the time it +takes to decode and the time it takes to build the table. If building the +table took no time (and if you had infinite memory), then there would only +be a first level table to cover all the way to the longest code. However, +building the table ends up taking a lot longer for more bits since short +codes are replicated many times in such a table. What inflate() does is +simply to make the number of bits in the first table a variable, and then +to set that variable for the maximum speed. + +For inflate, which has 286 possible codes for the literal/length tree, the size +of the first table is nine bits. Also the distance trees have 30 possible +values, and the size of the first table is six bits. Note that for each of +those cases, the table ended up one bit longer than the ``average'' code +length, i.e. the code length of an approximately flat code which would be a +little more than eight bits for 286 symbols and a little less than five bits +for 30 symbols. + + +2.2 More details on the inflate table lookup + +Ok, you want to know what this cleverly obfuscated inflate tree actually +looks like. You are correct that it's not a Huffman tree. It is simply a +lookup table for the first, let's say, nine bits of a Huffman symbol. The +symbol could be as short as one bit or as long as 15 bits. If a particular +symbol is shorter than nine bits, then that symbol's translation is duplicated +in all those entries that start with that symbol's bits. For example, if the +symbol is four bits, then it's duplicated 32 times in a nine-bit table. If a +symbol is nine bits long, it appears in the table once. + +If the symbol is longer than nine bits, then that entry in the table points +to another similar table for the remaining bits. Again, there are duplicated +entries as needed. The idea is that most of the time the symbol will be short +and there will only be one table look up. (That's whole idea behind data +compression in the first place.) For the less frequent long symbols, there +will be two lookups. If you had a compression method with really long +symbols, you could have as many levels of lookups as is efficient. For +inflate, two is enough. + +So a table entry either points to another table (in which case nine bits in +the above example are gobbled), or it contains the translation for the symbol +and the number of bits to gobble. Then you start again with the next +ungobbled bit. + +You may wonder: why not just have one lookup table for how ever many bits the +longest symbol is? The reason is that if you do that, you end up spending +more time filling in duplicate symbol entries than you do actually decoding. +At least for deflate's output that generates new trees every several 10's of +kbytes. You can imagine that filling in a 2^15 entry table for a 15-bit code +would take too long if you're only decoding several thousand symbols. At the +other extreme, you could make a new table for every bit in the code. In fact, +that's essentially a Huffman tree. But then you spend too much time +traversing the tree while decoding, even for short symbols. + +So the number of bits for the first lookup table is a trade of the time to +fill out the table vs. the time spent looking at the second level and above of +the table. + +Here is an example, scaled down: + +The code being decoded, with 10 symbols, from 1 to 6 bits long: + +A: 0 +B: 10 +C: 1100 +D: 11010 +E: 11011 +F: 11100 +G: 11101 +H: 11110 +I: 111110 +J: 111111 + +Let's make the first table three bits long (eight entries): + +000: A,1 +001: A,1 +010: A,1 +011: A,1 +100: B,2 +101: B,2 +110: -> table X (gobble 3 bits) +111: -> table Y (gobble 3 bits) + +Each entry is what the bits decode as and how many bits that is, i.e. how +many bits to gobble. Or the entry points to another table, with the number of +bits to gobble implicit in the size of the table. + +Table X is two bits long since the longest code starting with 110 is five bits +long: + +00: C,1 +01: C,1 +10: D,2 +11: E,2 + +Table Y is three bits long since the longest code starting with 111 is six +bits long: + +000: F,2 +001: F,2 +010: G,2 +011: G,2 +100: H,2 +101: H,2 +110: I,3 +111: J,3 + +So what we have here are three tables with a total of 20 entries that had to +be constructed. That's compared to 64 entries for a single table. Or +compared to 16 entries for a Huffman tree (six two entry tables and one four +entry table). Assuming that the code ideally represents the probability of +the symbols, it takes on the average 1.25 lookups per symbol. That's compared +to one lookup for the single table, or 1.66 lookups per symbol for the +Huffman tree. + +There, I think that gives you a picture of what's going on. For inflate, the +meaning of a particular symbol is often more than just a letter. It can be a +byte (a "literal"), or it can be either a length or a distance which +indicates a base value and a number of bits to fetch after the code that is +added to the base value. Or it might be the special end-of-block code. The +data structures created in inftrees.c try to encode all that information +compactly in the tables. + + +Jean-loup Gailly Mark Adler +jloup@gzip.org madler@alumni.caltech.edu + + +References: + +[LZ77] Ziv J., Lempel A., ``A Universal Algorithm for Sequential Data +Compression,'' IEEE Transactions on Information Theory, Vol. 23, No. 3, +pp. 337-343. + +``DEFLATE Compressed Data Format Specification'' available in +http://www.ietf.org/rfc/rfc1951.txt diff --git a/cpukit/zlib/gzclose.c b/cpukit/zlib/gzclose.c new file mode 100644 index 0000000000..caeb99a317 --- /dev/null +++ b/cpukit/zlib/gzclose.c @@ -0,0 +1,25 @@ +/* gzclose.c -- zlib gzclose() function + * Copyright (C) 2004, 2010 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +#include "gzguts.h" + +/* gzclose() is in a separate file so that it is linked in only if it is used. + That way the other gzclose functions can be used instead to avoid linking in + unneeded compression or decompression routines. */ +int ZEXPORT gzclose(file) + gzFile file; +{ +#ifndef NO_GZCOMPRESS + gz_statep state; + + if (file == NULL) + return Z_STREAM_ERROR; + state = (gz_statep)file; + + return state->mode == GZ_READ ? gzclose_r(file) : gzclose_w(file); +#else + return gzclose_r(file); +#endif +} diff --git a/cpukit/zlib/gzguts.h b/cpukit/zlib/gzguts.h new file mode 100644 index 0000000000..0e7ed4330a --- /dev/null +++ b/cpukit/zlib/gzguts.h @@ -0,0 +1,132 @@ +/* gzguts.h -- zlib internal header definitions for gz* operations + * Copyright (C) 2004, 2005, 2010 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +#ifdef _LARGEFILE64_SOURCE +# ifndef _LARGEFILE_SOURCE +# define _LARGEFILE_SOURCE +# endif +# ifdef _FILE_OFFSET_BITS +# undef _FILE_OFFSET_BITS +# endif +#endif + +#define ZLIB_INTERNAL + +#include +#include "zlib.h" +#ifdef STDC +# include +# include +# include +#endif +#include + +#ifdef NO_DEFLATE /* for compatibility with old definition */ +# define NO_GZCOMPRESS +#endif + +#ifdef _MSC_VER +# include +# define vsnprintf _vsnprintf +#endif + +#ifndef local +# define local static +#endif +/* compile with -Dlocal if your debugger can't find static symbols */ + +/* gz* functions always use library allocation functions */ +#ifndef STDC + extern voidp malloc OF((uInt size)); + extern void free OF((voidpf ptr)); +#endif + +/* get errno and strerror definition */ +#if defined UNDER_CE && defined NO_ERRNO_H +# include +# define zstrerror() gz_strwinerror((DWORD)GetLastError()) +#else +# ifdef STDC +# include +# define zstrerror() strerror(errno) +# else +# define zstrerror() "stdio error (consult errno)" +# endif +#endif + +/* MVS fdopen() */ +#ifdef __MVS__ + #pragma map (fdopen , "\174\174FDOPEN") + FILE *fdopen(int, const char *); +#endif + +#ifdef _LARGEFILE64_SOURCE +# define z_off64_t off64_t +#else +# define z_off64_t z_off_t +#endif + +/* default i/o buffer size -- double this for output when reading */ +#define GZBUFSIZE 8192 + +/* gzip modes, also provide a little integrity check on the passed structure */ +#define GZ_NONE 0 +#define GZ_READ 7247 +#define GZ_WRITE 31153 +#define GZ_APPEND 1 /* mode set to GZ_WRITE after the file is opened */ + +/* values for gz_state how */ +#define LOOK 0 /* look for a gzip header */ +#define COPY 1 /* copy input directly */ +#define GZIP 2 /* decompress a gzip stream */ + +/* internal gzip file state data structure */ +typedef struct { + /* used for both reading and writing */ + int mode; /* see gzip modes above */ + int fd; /* file descriptor */ + char *path; /* path or fd for error messages */ + z_off64_t pos; /* current position in uncompressed data */ + unsigned size; /* buffer size, zero if not allocated yet */ + unsigned want; /* requested buffer size, default is GZBUFSIZE */ + unsigned char *in; /* input buffer */ + unsigned char *out; /* output buffer (double-sized when reading) */ + unsigned char *next; /* next output data to deliver or write */ + /* just for reading */ + unsigned have; /* amount of output data unused at next */ + int eof; /* true if end of input file reached */ + z_off64_t start; /* where the gzip data started, for rewinding */ + z_off64_t raw; /* where the raw data started, for seeking */ + int how; /* 0: get header, 1: copy, 2: decompress */ + int direct; /* true if last read direct, false if gzip */ + /* just for writing */ + int level; /* compression level */ + int strategy; /* compression strategy */ + /* seek request */ + z_off64_t skip; /* amount to skip (already rewound if backwards) */ + int seek; /* true if seek request pending */ + /* error information */ + int err; /* error code */ + char *msg; /* error message */ + /* zlib inflate or deflate stream */ + z_stream strm; /* stream structure in-place (not a pointer) */ +} gz_state; +typedef gz_state FAR *gz_statep; + +/* shared functions */ +ZEXTERN void ZEXPORT gz_error OF((gz_statep, int, const char *)); +#if defined UNDER_CE && defined NO_ERRNO_H +ZEXTERN char ZEXPORT *gz_strwinerror OF((DWORD error)); +#endif + +/* GT_OFF(x), where x is an unsigned value, is true if x > maximum z_off64_t + value -- needed when comparing unsigned to z_off64_t, which is signed + (possible z_off64_t types off_t, off64_t, and long are all signed) */ +#ifdef INT_MAX +# define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > INT_MAX) +#else +ZEXTERN unsigned ZEXPORT gz_intmax OF((void)); +# define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > gz_intmax()) +#endif diff --git a/cpukit/zlib/gzlib.c b/cpukit/zlib/gzlib.c new file mode 100644 index 0000000000..6fdb08a814 --- /dev/null +++ b/cpukit/zlib/gzlib.c @@ -0,0 +1,535 @@ +/* gzlib.c -- zlib functions common to reading and writing gzip files + * Copyright (C) 2004, 2010 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +#include "gzguts.h" + +#ifdef _LARGEFILE64_SOURCE +# define LSEEK lseek64 +#else +# define LSEEK lseek +#endif + +/* Local functions */ +local void gz_reset OF((gz_statep)); +local gzFile gz_open OF((const char *, int, const char *)); + +#if defined UNDER_CE && defined NO_ERRNO_H + +/* Map the Windows error number in ERROR to a locale-dependent error message + string and return a pointer to it. Typically, the values for ERROR come + from GetLastError. + + The string pointed to shall not be modified by the application, but may be + overwritten by a subsequent call to gz_strwinerror + + The gz_strwinerror function does not change the current setting of + GetLastError. */ +char ZEXPORT *gz_strwinerror (error) + DWORD error; +{ + static char buf[1024]; + + wchar_t *msgbuf; + DWORD lasterr = GetLastError(); + DWORD chars = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM + | FORMAT_MESSAGE_ALLOCATE_BUFFER, + NULL, + error, + 0, /* Default language */ + (LPVOID)&msgbuf, + 0, + NULL); + if (chars != 0) { + /* If there is an \r\n appended, zap it. */ + if (chars >= 2 + && msgbuf[chars - 2] == '\r' && msgbuf[chars - 1] == '\n') { + chars -= 2; + msgbuf[chars] = 0; + } + + if (chars > sizeof (buf) - 1) { + chars = sizeof (buf) - 1; + msgbuf[chars] = 0; + } + + wcstombs(buf, msgbuf, chars + 1); + LocalFree(msgbuf); + } + else { + sprintf(buf, "unknown win32 error (%ld)", error); + } + + SetLastError(lasterr); + return buf; +} + +#endif /* UNDER_CE && NO_ERRNO_H */ + +/* Reset gzip file state */ +local void gz_reset(state) + gz_statep state; +{ + if (state->mode == GZ_READ) { /* for reading ... */ + state->have = 0; /* no output data available */ + state->eof = 0; /* not at end of file */ + state->how = LOOK; /* look for gzip header */ + state->direct = 1; /* default for empty file */ + } + state->seek = 0; /* no seek request pending */ + gz_error(state, Z_OK, NULL); /* clear error */ + state->pos = 0; /* no uncompressed data yet */ + state->strm.avail_in = 0; /* no input data yet */ +} + +/* Open a gzip file either by name or file descriptor. */ +local gzFile gz_open(path, fd, mode) + const char *path; + int fd; + const char *mode; +{ + gz_statep state; + + /* allocate gzFile structure to return */ + state = malloc(sizeof(gz_state)); + if (state == NULL) + return NULL; + state->size = 0; /* no buffers allocated yet */ + state->want = GZBUFSIZE; /* requested buffer size */ + state->msg = NULL; /* no error message yet */ + + /* interpret mode */ + state->mode = GZ_NONE; + state->level = Z_DEFAULT_COMPRESSION; + state->strategy = Z_DEFAULT_STRATEGY; + while (*mode) { + if (*mode >= '0' && *mode <= '9') + state->level = *mode - '0'; + else + switch (*mode) { + case 'r': + state->mode = GZ_READ; + break; +#ifndef NO_GZCOMPRESS + case 'w': + state->mode = GZ_WRITE; + break; + case 'a': + state->mode = GZ_APPEND; + break; +#endif + case '+': /* can't read and write at the same time */ + free(state); + return NULL; + case 'b': /* ignore -- will request binary anyway */ + break; + case 'f': + state->strategy = Z_FILTERED; + break; + case 'h': + state->strategy = Z_HUFFMAN_ONLY; + break; + case 'R': + state->strategy = Z_RLE; + break; + case 'F': + state->strategy = Z_FIXED; + default: /* could consider as an error, but just ignore */ + ; + } + mode++; + } + + /* must provide an "r", "w", or "a" */ + if (state->mode == GZ_NONE) { + free(state); + return NULL; + } + + /* save the path name for error messages */ + state->path = malloc(strlen(path) + 1); + if (state->path == NULL) { + free(state); + return NULL; + } + strcpy(state->path, path); + + /* open the file with the appropriate mode (or just use fd) */ + state->fd = fd != -1 ? fd : + open(path, +#ifdef O_LARGEFILE + O_LARGEFILE | +#endif +#ifdef O_BINARY + O_BINARY | +#endif + (state->mode == GZ_READ ? + O_RDONLY : + (O_WRONLY | O_CREAT | ( + state->mode == GZ_WRITE ? + O_TRUNC : + O_APPEND))), + 0666); + if (state->fd == -1) { + free(state); + return NULL; + } + if (state->mode == GZ_APPEND) + state->mode = GZ_WRITE; /* simplify later checks */ + + /* save the current position for rewinding (only if reading) */ + if (state->mode == GZ_READ) { + state->start = LSEEK(state->fd, 0, SEEK_CUR); + if (state->start == -1) state->start = 0; + } + + /* initialize stream */ + gz_reset(state); + + /* return stream */ + return (gzFile)state; +} + +/* -- see zlib.h -- */ +gzFile ZEXPORT gzopen(path, mode) + const char *path; + const char *mode; +{ + return gz_open(path, -1, mode); +} + +/* -- see zlib.h -- */ +gzFile ZEXPORT gzopen64(path, mode) + const char *path; + const char *mode; +{ + return gz_open(path, -1, mode); +} + +/* -- see zlib.h -- */ +gzFile ZEXPORT gzdopen(fd, mode) + int fd; + const char *mode; +{ + char *path; /* identifier for error messages */ + gzFile gz; + + if (fd == -1 || (path = malloc(7 + 3 * sizeof(int))) == NULL) + return NULL; + sprintf(path, "", fd); + gz = gz_open(path, fd, mode); + free(path); + return gz; +} + +/* -- see zlib.h -- */ +int ZEXPORT gzbuffer(file, size) + gzFile file; + unsigned size; +{ + gz_statep state; + + /* get internal structure and check integrity */ + if (file == NULL) + return -1; + state = (gz_statep)file; + if (state->mode != GZ_READ && state->mode != GZ_WRITE) + return -1; + + /* make sure we haven't already allocated memory */ + if (state->size != 0) + return -1; + + /* check and set requested size */ + if (size == 0) + return -1; + state->want = size; + return 0; +} + +/* -- see zlib.h -- */ +int ZEXPORT gzrewind(file) + 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 error */ + if (state->mode != GZ_READ || state->err != Z_OK) + return -1; + + /* back up and start over */ + if (LSEEK(state->fd, state->start, SEEK_SET) == -1) + return -1; + gz_reset(state); + return 0; +} + +/* -- see zlib.h -- */ +z_off64_t ZEXPORT gzseek64(file, offset, whence) + gzFile file; + z_off64_t offset; + int whence; +{ + unsigned n; + z_off64_t ret; + gz_statep state; + + /* get internal structure and check integrity */ + if (file == NULL) + return -1; + state = (gz_statep)file; + if (state->mode != GZ_READ && state->mode != GZ_WRITE) + return -1; + + /* check that there's no error */ + if (state->err != Z_OK) + return -1; + + /* can only seek from start or relative to current position */ + if (whence != SEEK_SET && whence != SEEK_CUR) + return -1; + + /* normalize offset to a SEEK_CUR specification */ + if (whence == SEEK_SET) + offset -= state->pos; + else if (state->seek) + offset += state->skip; + state->seek = 0; + + /* if within raw area while reading, just go there */ + if (state->mode == GZ_READ && state->how == COPY && + state->pos + offset >= state->raw) { + ret = LSEEK(state->fd, offset, SEEK_CUR); + if (ret == -1) + return -1; + state->have = 0; + state->eof = 0; + state->seek = 0; + gz_error(state, Z_OK, NULL); + state->strm.avail_in = 0; + state->pos += offset; + return state->pos; + } + + /* calculate skip amount, rewinding if needed for back seek when reading */ + if (offset < 0) { + if (state->mode != GZ_READ) /* writing -- can't go backwards */ + return -1; + offset += state->pos; + if (offset < 0) /* before start of file! */ + return -1; + if (gzrewind(file) == -1) /* rewind, then skip to offset */ + return -1; + } + + /* if reading, skip what's in output buffer (one less gzgetc() check) */ + if (state->mode == GZ_READ) { + n = GT_OFF(state->have) || (z_off64_t)state->have > offset ? + (unsigned)offset : state->have; + state->have -= n; + state->next += n; + state->pos += n; + offset -= n; + } + + /* request skip (if not zero) */ + if (offset) { + state->seek = 1; + state->skip = offset; + } + return state->pos + offset; +} + +/* -- see zlib.h -- */ +z_off_t ZEXPORT gzseek(file, offset, whence) + gzFile file; + z_off_t offset; + int whence; +{ + z_off64_t ret; + + ret = gzseek64(file, (z_off64_t)offset, whence); + return ret == (z_off_t)ret ? (z_off_t)ret : -1; +} + +/* -- see zlib.h -- */ +z_off64_t ZEXPORT gztell64(file) + gzFile file; +{ + gz_statep state; + + /* get internal structure and check integrity */ + if (file == NULL) + return -1; + state = (gz_statep)file; + if (state->mode != GZ_READ && state->mode != GZ_WRITE) + return -1; + + /* return position */ + return state->pos + (state->seek ? state->skip : 0); +} + +/* -- see zlib.h -- */ +z_off_t ZEXPORT gztell(file) + gzFile file; +{ + z_off64_t ret; + + ret = gztell64(file); + return ret == (z_off_t)ret ? (z_off_t)ret : -1; +} + +/* -- see zlib.h -- */ +z_off64_t ZEXPORT gzoffset64(file) + gzFile file; +{ + z_off64_t offset; + gz_statep state; + + /* get internal structure and check integrity */ + if (file == NULL) + return -1; + state = (gz_statep)file; + if (state->mode != GZ_READ && state->mode != GZ_WRITE) + return -1; + + /* compute and return effective offset in file */ + offset = LSEEK(state->fd, 0, SEEK_CUR); + if (offset == -1) + return -1; + if (state->mode == GZ_READ) /* reading */ + offset -= state->strm.avail_in; /* don't count buffered input */ + return offset; +} + +/* -- see zlib.h -- */ +z_off_t ZEXPORT gzoffset(file) + gzFile file; +{ + z_off64_t ret; + + ret = gzoffset64(file); + return ret == (z_off_t)ret ? (z_off_t)ret : -1; +} + +/* -- see zlib.h -- */ +int ZEXPORT gzeof(file) + gzFile file; +{ + gz_statep state; + + /* get internal structure and check integrity */ + if (file == NULL) + return 0; + state = (gz_statep)file; + if (state->mode != GZ_READ && state->mode != GZ_WRITE) + return 0; + + /* return end-of-file state */ + return state->mode == GZ_READ ? (state->eof && state->have == 0) : 0; +} + +/* -- see zlib.h -- */ +const char * ZEXPORT gzerror(file, errnum) + gzFile file; + int *errnum; +{ + gz_statep state; + + /* get internal structure and check integrity */ + if (file == NULL) + return NULL; + state = (gz_statep)file; + if (state->mode != GZ_READ && state->mode != GZ_WRITE) + return NULL; + + /* return error information */ + if (errnum != NULL) + *errnum = state->err; + return state->msg == NULL ? "" : state->msg; +} + +/* -- see zlib.h -- */ +void ZEXPORT gzclearerr(file) + gzFile file; +{ + gz_statep state; + + /* get internal structure and check integrity */ + if (file == NULL) + return; + state = (gz_statep)file; + if (state->mode != GZ_READ && state->mode != GZ_WRITE) + return; + + /* clear error and end-of-file */ + if (state->mode == GZ_READ) + state->eof = 0; + gz_error(state, Z_OK, NULL); +} + +/* Create an error message in allocated memory and set state->err and + state->msg accordingly. Free any previous error message already there. Do + not try to free or allocate space if the error is Z_MEM_ERROR (out of + memory). Simply save the error message as a static string. If there is an + allocation failure constructing the error message, then convert the error to + out of memory. */ +void ZEXPORT gz_error(state, err, msg) + gz_statep state; + int err; + const char *msg; +{ + /* free previously allocated message and clear */ + if (state->msg != NULL) { + if (state->err != Z_MEM_ERROR) + free(state->msg); + state->msg = NULL; + } + + /* set error code, and if no message, then done */ + state->err = err; + if (msg == NULL) + return; + + /* for an out of memory error, save as static string */ + if (err == Z_MEM_ERROR) { + state->msg = (char *)msg; + return; + } + + /* construct error message with path */ + if ((state->msg = malloc(strlen(state->path) + strlen(msg) + 3)) == NULL) { + state->err = Z_MEM_ERROR; + state->msg = (char *)"out of memory"; + return; + } + strcpy(state->msg, state->path); + strcat(state->msg, ": "); + strcat(state->msg, msg); + return; +} + +#ifndef INT_MAX +/* portably return maximum value for an int (when limits.h presumed not + available) -- we need to do this to cover cases where 2's complement not + used, since C standard permits 1's complement and sign-bit representations, + otherwise we could just use ((unsigned)-1) >> 1 */ +unsigned ZEXPORT gz_intmax() +{ + unsigned p, q; + + p = 1; + do { + q = p; + p <<= 1; + p++; + } while (p > q); + return q >> 1; +} +#endif diff --git a/cpukit/zlib/gzread.c b/cpukit/zlib/gzread.c new file mode 100644 index 0000000000..434ef023e0 --- /dev/null +++ b/cpukit/zlib/gzread.c @@ -0,0 +1,652 @@ +/* gzread.c -- zlib functions for reading gzip files + * Copyright (C) 2004, 2005, 2010 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_next4 OF((gz_statep, unsigned long *)); +local int gz_head OF((gz_statep)); +local int gz_decomp OF((gz_statep)); +local int gz_make 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. + gz_avail() assumes that strm->avail_in == 0. */ +local int gz_avail(state) + gz_statep state; +{ + z_streamp strm = &(state->strm); + + if (state->err != Z_OK) + return -1; + if (state->eof == 0) { + if (gz_load(state, state->in, state->size, &(strm->avail_in)) == -1) + return -1; + strm->next_in = state->in; + } + return 0; +} + +/* Get next byte from input, or -1 if end or error. */ +#define NEXT() ((strm->avail_in == 0 && gz_avail(state) == -1) ? -1 : \ + (strm->avail_in == 0 ? -1 : \ + (strm->avail_in--, *(strm->next_in)++))) + +/* Get a four-byte little-endian integer and return 0 on success and the value + in *ret. Otherwise -1 is returned and *ret is not modified. */ +local int gz_next4(state, ret) + gz_statep state; + unsigned long *ret; +{ + int ch; + unsigned long val; + z_streamp strm = &(state->strm); + + val = NEXT(); + val += (unsigned)NEXT() << 8; + val += (unsigned long)NEXT() << 16; + ch = NEXT(); + if (ch == -1) + return -1; + val += (unsigned long)ch << 24; + *ret = val; + return 0; +} + +/* Look for gzip header, set up for inflate or copy. state->have must be zero. + 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, and the gzip header will be skipped so + that the next available input data is the raw deflate stream. 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 and the check value will be initialized. gz_head() will return 0 on + success or -1 on failure. Failures may include read errors or gzip header + errors. */ +local int gz_head(state) + gz_statep state; +{ + z_streamp strm = &(state->strm); + int flags; + unsigned len; + + /* 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) != Z_OK) { /* raw inflate */ + free(state->out); + free(state->in); + state->size = 0; + gz_error(state, Z_MEM_ERROR, "out of memory"); + return -1; + } + } + + /* get some data in the input buffer */ + if (strm->avail_in == 0) { + if (gz_avail(state) == -1) + return -1; + if (strm->avail_in == 0) + return 0; + } + + /* look for the gzip magic header bytes 31 and 139 */ + if (strm->next_in[0] == 31) { + strm->avail_in--; + strm->next_in++; + if (strm->avail_in == 0 && gz_avail(state) == -1) + return -1; + if (strm->avail_in && strm->next_in[0] == 139) { + /* we have a gzip header, woo hoo! */ + strm->avail_in--; + strm->next_in++; + + /* skip rest of header */ + if (NEXT() != 8) { /* compression method */ + gz_error(state, Z_DATA_ERROR, "unknown compression method"); + return -1; + } + flags = NEXT(); + if (flags & 0xe0) { /* reserved flag bits */ + gz_error(state, Z_DATA_ERROR, "unknown header flags set"); + return -1; + } + NEXT(); /* modification time */ + NEXT(); + NEXT(); + NEXT(); + NEXT(); /* extra flags */ + NEXT(); /* operating system */ + if (flags & 4) { /* extra field */ + len = (unsigned)NEXT(); + len += (unsigned)NEXT() << 8; + while (len--) + if (NEXT() < 0) + break; + } + if (flags & 8) /* file name */ + while (NEXT() > 0) + ; + if (flags & 16) /* comment */ + while (NEXT() > 0) + ; + if (flags & 2) { /* header crc */ + NEXT(); + NEXT(); + } + /* an unexpected end of file is not checked for here -- it will be + noticed on the first request for uncompressed data */ + + /* set up for decompression */ + inflateReset(strm); + strm->adler = crc32(0L, Z_NULL, 0); + state->how = GZIP; + state->direct = 0; + return 0; + } + else { + /* not a gzip file -- save first byte (31) and fall to raw i/o */ + state->out[0] = 31; + state->have = 1; + } + } + + /* doing raw i/o, save start of raw data for seeking, 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->raw = state->pos; + state->next = state->out; + if (strm->avail_in) { + memcpy(state->next + state->have, strm->next_in, strm->avail_in); + state->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. + If the end of the compressed data is reached, then verify the gzip trailer + check value and length (modulo 2^32). state->have and state->next are set + to point to the just decompressed data, and the crc is updated. If the + trailer is verified, state->how is reset to LOOK to look for the next gzip + stream or raw data, once state->have is depleted. Returns 0 on success, -1 + on failure. Failures may include invalid compressed data or a failed gzip + trailer verification. */ +local int gz_decomp(state) + gz_statep state; +{ + int ret; + unsigned had; + unsigned long crc, len; + 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_DATA_ERROR, "unexpected end of file"); + return -1; + } + + /* 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 and crc check value */ + state->have = had - strm->avail_out; + state->next = strm->next_out - state->have; + strm->adler = crc32(strm->adler, state->next, state->have); + + /* check gzip trailer if at end of deflate stream */ + if (ret == Z_STREAM_END) { + if (gz_next4(state, &crc) == -1 || gz_next4(state, &len) == -1) { + gz_error(state, Z_DATA_ERROR, "unexpected end of file"); + return -1; + } + if (crc != strm->adler) { + gz_error(state, Z_DATA_ERROR, "incorrect data check"); + return -1; + } + if (len != (strm->total_out & 0xffffffffL)) { + gz_error(state, Z_DATA_ERROR, "incorrect length check"); + return -1; + } + state->how = LOOK; /* ready for next stream, once have is 0 (leave + state->direct unchanged to remember how) */ + } + + /* good decompression */ + return 0; +} + +/* Make data and put in the output buffer. Assumes that state->have == 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 (and skipped if found) to determine wither to copy or decompress. + Returns -1 on error, otherwise 0. gz_make() will leave state->have as COPY + or GZIP unless the end of the input file has been reached and all data has + been processed. */ +local int gz_make(state) + gz_statep state; +{ + z_streamp strm = &(state->strm); + + if (state->how == LOOK) { /* look for gzip header */ + if (gz_head(state) == -1) + return -1; + if (state->have) /* got some data from gz_head() */ + return 0; + } + if (state->how == COPY) { /* straight copy */ + if (gz_load(state, state->out, state->size << 1, &(state->have)) == -1) + return -1; + state->next = state->out; + } + else if (state->how == GZIP) { /* decompress */ + strm->avail_out = state->size << 1; + strm->next_out = state->out; + if (gz_decomp(state) == -1) + return -1; + } + 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->have) { + n = GT_OFF(state->have) || (z_off64_t)state->have > len ? + (unsigned)len : state->have; + state->have -= n; + state->next += n; + state->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_make(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 error */ + if (state->mode != GZ_READ || state->err != Z_OK) + 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_BUF_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->have) { + n = state->have > len ? len : state->have; + memcpy(buf, state->next, n); + state->next += n; + state->have -= n; + } + + /* output buffer empty -- return if we're at the end of the input */ + else if (state->eof && strm->avail_in == 0) + 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_make(state) == -1) + return -1; + continue; /* no progress yet -- go back to memcpy() 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->have; + state->have = 0; + } + + /* update progress */ + len -= n; + buf = (char *)buf + n; + got += n; + state->pos += n; + } while (len); + + /* return number of bytes read into user buffer (will fit in int) */ + return (int)got; +} + +/* -- see zlib.h -- */ +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 error */ + if (state->mode != GZ_READ || state->err != Z_OK) + return -1; + + /* try output buffer (no need to check for skip request) */ + if (state->have) { + state->have--; + state->pos++; + return *(state->next)++; + } + + /* nothing there -- try gzread() */ + ret = gzread(file, buf, 1); + return ret < 1 ? -1 : buf[0]; +} + +/* -- 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 error */ + if (state->mode != GZ_READ || state->err != Z_OK) + 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->have == 0) { + state->have = 1; + state->next = state->out + (state->size << 1) - 1; + state->next[0] = c; + state->pos--; + return c; + } + + /* if no room, give up (must have already done a gzungetc()) */ + if (state->have == (state->size << 1)) { + gz_error(state, Z_BUF_ERROR, "out of room to push characters"); + return -1; + } + + /* slide output data if needed and insert byte before existing data */ + if (state->next == state->out) { + unsigned char *src = state->out + state->have; + unsigned char *dest = state->out + (state->size << 1); + while (src > state->out) + *--dest = *--src; + state->next = dest; + } + state->have++; + state->next--; + state->next[0] = c; + state->pos--; + 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 error */ + if (state->mode != GZ_READ || state->err != Z_OK) + 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->have == 0) { + if (gz_make(state) == -1) + return NULL; /* error */ + if (state->have == 0) { /* end of file */ + if (buf == str) /* got bupkus */ + return NULL; + break; /* got something -- return it */ + } + } + + /* look for end-of-line in current output buffer */ + n = state->have > left ? left : state->have; + eol = memchr(state->next, '\n', n); + if (eol != NULL) + n = (unsigned)(eol - state->next) + 1; + + /* copy through end-of-line, or remainder if not found */ + memcpy(buf, state->next, n); + state->have -= n; + state->next += n; + state->pos += n; + left -= n; + buf += n; + } while (left && eol == NULL); + + /* found end-of-line or out of space -- terminate string and return it */ + 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; + + /* check that we're reading */ + if (state->mode != GZ_READ) + return 0; + + /* 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->how == LOOK && state->have == 0) + (void)gz_head(state); + + /* return 1 if reading direct, 0 if decompressing a gzip stream */ + return state->direct; +} + +/* -- see zlib.h -- */ +int ZEXPORT gzclose_r(file) + gzFile file; +{ + int ret; + 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); + } + gz_error(state, Z_OK, NULL); + free(state->path); + ret = close(state->fd); + free(state); + return ret ? Z_ERRNO : Z_OK; +} diff --git a/cpukit/zlib/gzwrite.c b/cpukit/zlib/gzwrite.c new file mode 100644 index 0000000000..e8defc6887 --- /dev/null +++ b/cpukit/zlib/gzwrite.c @@ -0,0 +1,531 @@ +/* gzwrite.c -- zlib functions for writing gzip files + * Copyright (C) 2004, 2005, 2010 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +#include "gzguts.h" + +/* Local functions */ +local int gz_init OF((gz_statep)); +local int gz_comp OF((gz_statep, int)); +local int gz_zero OF((gz_statep, z_off64_t)); + +/* Initialize state for writing a gzip file. Mark initialization by setting + state->size to non-zero. Return -1 on failure or 0 on success. */ +local int gz_init(state) + gz_statep state; +{ + int ret; + z_streamp strm = &(state->strm); + + /* allocate input and output buffers */ + state->in = malloc(state->want); + state->out = malloc(state->want); + 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; + } + + /* allocate deflate memory, set up for gzip compression */ + strm->zalloc = Z_NULL; + strm->zfree = Z_NULL; + strm->opaque = Z_NULL; + ret = deflateInit2(strm, state->level, Z_DEFLATED, + 15 + 16, 8, state->strategy); + if (ret != Z_OK) { + free(state->in); + gz_error(state, Z_MEM_ERROR, "out of memory"); + return -1; + } + + /* mark state as initialized */ + state->size = state->want; + + /* initialize write buffer */ + strm->avail_out = state->size; + strm->next_out = state->out; + state->next = strm->next_out; + return 0; +} + +/* Compress whatever is at avail_in and next_in and write to the output file. + Return -1 if there is an error writing to the output file, otherwise 0. + flush is assumed to be a valid deflate() flush value. If flush is Z_FINISH, + then the deflate() state is reset to start a new gzip stream. */ +local int gz_comp(state, flush) + gz_statep state; + int flush; +{ + int ret, got; + unsigned have; + z_streamp strm = &(state->strm); + + /* allocate memory if this is the first time through */ + if (state->size == 0 && gz_init(state) == -1) + return -1; + + /* run deflate() on provided input until it produces no more output */ + ret = Z_OK; + do { + /* write out current buffer contents if full, or if flushing, but if + doing Z_FINISH then don't write until we get to Z_STREAM_END */ + if (strm->avail_out == 0 || (flush != Z_NO_FLUSH && + (flush != Z_FINISH || ret == Z_STREAM_END))) { + have = (unsigned)(strm->next_out - state->next); + if (have && ((got = write(state->fd, state->next, have)) < 0 || + (unsigned)got != have)) { + gz_error(state, Z_ERRNO, zstrerror()); + return -1; + } + if (strm->avail_out == 0) { + strm->avail_out = state->size; + strm->next_out = state->out; + } + state->next = strm->next_out; + } + + /* compress */ + have = strm->avail_out; + ret = deflate(strm, flush); + if (ret == Z_STREAM_ERROR) { + gz_error(state, Z_STREAM_ERROR, + "internal error: deflate stream corrupt"); + return -1; + } + have -= strm->avail_out; + } while (have); + + /* if that completed a deflate stream, allow another to start */ + if (flush == Z_FINISH) + deflateReset(strm); + + /* all done, no errors */ + return 0; +} + +/* Compress len zeros to output. Return -1 on error, 0 on success. */ +local int gz_zero(state, len) + gz_statep state; + z_off64_t len; +{ + int first; + unsigned n; + z_streamp strm = &(state->strm); + + /* consume whatever's left in the input buffer */ + if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1) + return -1; + + /* compress len zeros (len guaranteed > 0) */ + first = 1; + while (len) { + n = GT_OFF(state->size) || (z_off64_t)state->size > len ? + (unsigned)len : state->size; + if (first) { + memset(state->in, 0, n); + first = 0; + } + strm->avail_in = n; + strm->next_in = state->in; + state->pos += n; + if (gz_comp(state, Z_NO_FLUSH) == -1) + return -1; + len -= n; + } + return 0; +} + +/* -- see zlib.h -- */ +int ZEXPORT gzwrite(file, buf, len) + gzFile file; + voidpc buf; + unsigned len; +{ + unsigned put = len; + unsigned n; + gz_statep state; + z_streamp strm; + + /* get internal structure */ + if (file == NULL) + return 0; + state = (gz_statep)file; + strm = &(state->strm); + + /* check that we're writing and that there's no error */ + if (state->mode != GZ_WRITE || state->err != Z_OK) + return 0; + + /* 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_BUF_ERROR, "requested length does not fit in int"); + return 0; + } + + /* if len is zero, avoid unnecessary operations */ + if (len == 0) + return 0; + + /* allocate memory if this is the first time through */ + if (state->size == 0 && gz_init(state) == -1) + return 0; + + /* check for seek request */ + if (state->seek) { + state->seek = 0; + if (gz_zero(state, state->skip) == -1) + return 0; + } + + /* for small len, copy to input buffer, otherwise compress directly */ + if (len < state->size) { + /* copy to input buffer, compress when full */ + do { + if (strm->avail_in == 0) + strm->next_in = state->in; + n = state->size - strm->avail_in; + if (n > len) + n = len; + memcpy(strm->next_in + strm->avail_in, buf, n); + strm->avail_in += n; + state->pos += n; + buf = (char *)buf + n; + len -= n; + if (len && gz_comp(state, Z_NO_FLUSH) == -1) + return 0; + } while (len); + } + else { + /* consume whatever's left in the input buffer */ + if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1) + return 0; + + /* directly compress user buffer to file */ + strm->avail_in = len; + strm->next_in = (voidp)buf; + state->pos += len; + if (gz_comp(state, Z_NO_FLUSH) == -1) + return 0; + } + + /* input was all buffered or compressed (put will fit in int) */ + return (int)put; +} + +/* -- see zlib.h -- */ +int ZEXPORT gzputc(file, c) + gzFile file; + int c; +{ + unsigned char buf[1]; + 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 writing and that there's no error */ + if (state->mode != GZ_WRITE || state->err != Z_OK) + return -1; + + /* check for seek request */ + if (state->seek) { + state->seek = 0; + if (gz_zero(state, state->skip) == -1) + return -1; + } + + /* try writing to input buffer for speed (state->size == 0 if buffer not + initialized) */ + if (strm->avail_in < state->size) { + if (strm->avail_in == 0) + strm->next_in = state->in; + strm->next_in[strm->avail_in++] = c; + state->pos++; + return c; + } + + /* no room in buffer or not initialized, use gz_write() */ + buf[0] = c; + if (gzwrite(file, buf, 1) != 1) + return -1; + return c; +} + +/* -- see zlib.h -- */ +int ZEXPORT gzputs(file, str) + gzFile file; + const char *str; +{ + int ret; + unsigned len; + + /* write string */ + len = (unsigned)strlen(str); + ret = gzwrite(file, str, len); + return ret == 0 && len != 0 ? -1 : ret; +} + +#ifdef STDC +#include + +/* -- see zlib.h -- */ +int ZEXPORTVA gzprintf (gzFile file, const char *format, ...) +{ + int size, len; + gz_statep state; + z_streamp strm; + va_list va; + + /* get internal structure */ + if (file == NULL) + return -1; + state = (gz_statep)file; + strm = &(state->strm); + + /* check that we're writing and that there's no error */ + if (state->mode != GZ_WRITE || state->err != Z_OK) + return 0; + + /* make sure we have some buffer space */ + if (state->size == 0 && gz_init(state) == -1) + return 0; + + /* check for seek request */ + if (state->seek) { + state->seek = 0; + if (gz_zero(state, state->skip) == -1) + return 0; + } + + /* consume whatever's left in the input buffer */ + if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1) + return 0; + + /* do the printf() into the input buffer, put length in len */ + size = (int)(state->size); + state->in[size - 1] = 0; + va_start(va, format); +#ifdef NO_vsnprintf +# ifdef HAS_vsprintf_void + (void)vsprintf(state->in, format, va); + va_end(va); + for (len = 0; len < size; len++) + if (state->in[len] == 0) break; +# else + len = vsprintf(state->in, format, va); + va_end(va); +# endif +#else +# ifdef HAS_vsnprintf_void + (void)vsnprintf(state->in, size, format, va); + va_end(va); + len = strlen(state->in); +# else + len = vsnprintf((char *)(state->in), size, format, va); + va_end(va); +# endif +#endif + + /* check that printf() results fit in buffer */ + if (len <= 0 || len >= (int)size || state->in[size - 1] != 0) + return 0; + + /* update buffer and position, defer compression until needed */ + strm->avail_in = (unsigned)len; + strm->next_in = state->in; + state->pos += len; + return len; +} + +#else /* !STDC */ + +/* -- see zlib.h -- */ +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; +{ + int size, len; + 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 writing and that there's no error */ + if (state->mode != GZ_WRITE || state->err != Z_OK) + return 0; + + /* make sure we have some buffer space */ + if (state->size == 0 && gz_init(state) == -1) + return 0; + + /* check for seek request */ + if (state->seek) { + state->seek = 0; + if (gz_zero(state, state->skip) == -1) + return 0; + } + + /* consume whatever's left in the input buffer */ + if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1) + return 0; + + /* do the printf() into the input buffer, put length in len */ + size = (int)(state->size); + state->in[size - 1] = 0; +#ifdef NO_snprintf +# ifdef HAS_sprintf_void + sprintf(state->in, format, a1, a2, a3, a4, a5, a6, a7, a8, + a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20); + for (len = 0; len < size; len++) + if (state->in[len] == 0) break; +# else + len = sprintf(state->in, format, a1, a2, a3, a4, a5, a6, a7, a8, + a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20); +# endif +#else +# ifdef HAS_snprintf_void + snprintf(state->in, size, format, a1, a2, a3, a4, a5, a6, a7, a8, + a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20); + len = strlen(state->in); +# else + len = snprintf(state->in, size, format, a1, a2, a3, a4, a5, a6, a7, a8, + a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20); +# endif +#endif + + /* check that printf() results fit in buffer */ + if (len <= 0 || len >= (int)size || state->in[size - 1] != 0) + return 0; + + /* update buffer and position, defer compression until needed */ + strm->avail_in = (unsigned)len; + strm->next_in = state->in; + state->pos += len; + return len; +} + +#endif + +/* -- see zlib.h -- */ +int ZEXPORT gzflush(file, flush) + gzFile file; + int flush; +{ + gz_statep state; + + /* get internal structure */ + if (file == NULL) + return -1; + state = (gz_statep)file; + + /* check that we're writing and that there's no error */ + if (state->mode != GZ_WRITE || state->err != Z_OK) + return Z_STREAM_ERROR; + + /* check flush parameter */ + if (flush < 0 || flush > Z_FINISH) + return Z_STREAM_ERROR; + + /* check for seek request */ + if (state->seek) { + state->seek = 0; + if (gz_zero(state, state->skip) == -1) + return -1; + } + + /* compress remaining data with requested flush */ + gz_comp(state, flush); + return state->err; +} + +/* -- see zlib.h -- */ +int ZEXPORT gzsetparams(file, level, strategy) + gzFile file; + int level; + int strategy; +{ + gz_statep state; + z_streamp strm; + + /* get internal structure */ + if (file == NULL) + return Z_STREAM_ERROR; + state = (gz_statep)file; + strm = &(state->strm); + + /* check that we're writing and that there's no error */ + if (state->mode != GZ_WRITE || state->err != Z_OK) + return Z_STREAM_ERROR; + + /* if no change is requested, then do nothing */ + if (level == state->level && strategy == state->strategy) + return Z_OK; + + /* check for seek request */ + if (state->seek) { + state->seek = 0; + if (gz_zero(state, state->skip) == -1) + return -1; + } + + /* change compression parameters for subsequent input */ + if (state->size) { + /* flush previous input with previous parameters before changing */ + if (strm->avail_in && gz_comp(state, Z_PARTIAL_FLUSH) == -1) + return state->err; + deflateParams(strm, level, strategy); + } + state->level = level; + state->strategy = strategy; + return Z_OK; +} + +/* -- see zlib.h -- */ +int ZEXPORT gzclose_w(file) + gzFile file; +{ + int ret = 0; + gz_statep state; + + /* get internal structure */ + if (file == NULL) + return Z_STREAM_ERROR; + state = (gz_statep)file; + + /* check that we're writing */ + if (state->mode != GZ_WRITE) + return Z_STREAM_ERROR; + + /* check for seek request */ + if (state->seek) { + state->seek = 0; + ret += gz_zero(state, state->skip); + } + + /* flush, free memory, and close file */ + ret += gz_comp(state, Z_FINISH); + (void)deflateEnd(&(state->strm)); + free(state->out); + free(state->in); + gz_error(state, Z_OK, NULL); + free(state->path); + ret += close(state->fd); + free(state); + return ret ? Z_ERRNO : Z_OK; +} -- cgit v1.2.3