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Diffstat (limited to 'contrib/cvs/src/zlib.c')
| -rw-r--r-- | contrib/cvs/src/zlib.c | 760 |
1 files changed, 0 insertions, 760 deletions
diff --git a/contrib/cvs/src/zlib.c b/contrib/cvs/src/zlib.c deleted file mode 100644 index 46ed0e6..0000000 --- a/contrib/cvs/src/zlib.c +++ /dev/null @@ -1,760 +0,0 @@ -/* zlib.c --- interface to the zlib compression library - Ian Lance Taylor <ian@cygnus.com> - - This file is part of GNU CVS. - - GNU CVS is free software; you can redistribute it and/or modify it - under the terms of the GNU General Public License as published by the - Free Software Foundation; either version 2, or (at your option) any - later version. - - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. */ - -/* The routines in this file are the interface between the CVS - client/server support and the zlib compression library. */ - -#include <assert.h> -#include "cvs.h" -#include "buffer.h" - -#if defined (SERVER_SUPPORT) || defined (CLIENT_SUPPORT) - -#include "zlib.h" - -/* OS/2 doesn't have EIO. FIXME: this whole notion of turning - a different error into EIO strikes me as pretty dubious. */ -#if !defined (EIO) -#define EIO EBADPOS -#endif - -/* The compression interface is built upon the buffer data structure. - We provide a buffer type which compresses or decompresses the data - which passes through it. An input buffer decompresses the data - read from an underlying buffer, and an output buffer compresses the - data before writing it to an underlying buffer. */ - -/* This structure is the closure field of the buffer. */ - -struct compress_buffer -{ - /* The underlying buffer. */ - struct buffer *buf; - /* The compression information. */ - z_stream zstr; -}; - -static void compress_error PROTO((int, int, z_stream *, const char *)); -static int compress_buffer_input PROTO((void *, char *, int, int, int *)); -static int compress_buffer_output PROTO((void *, const char *, int, int *)); -static int compress_buffer_flush PROTO((void *)); -static int compress_buffer_block PROTO((void *, int)); -static int compress_buffer_shutdown_input PROTO((struct buffer *)); -static int compress_buffer_shutdown_output PROTO((struct buffer *)); - -/* Report an error from one of the zlib functions. */ - -static void -compress_error (status, zstatus, zstr, msg) - int status; - int zstatus; - z_stream *zstr; - const char *msg; -{ - int hold_errno; - const char *zmsg; - char buf[100]; - - hold_errno = errno; - - zmsg = zstr->msg; - if (zmsg == NULL) - { - sprintf (buf, "error %d", zstatus); - zmsg = buf; - } - - error (status, - zstatus == Z_ERRNO ? hold_errno : 0, - "%s: %s", msg, zmsg); -} - -/* Create a compression buffer. */ - -struct buffer * -compress_buffer_initialize (buf, input, level, memory) - struct buffer *buf; - int input; - int level; - void (*memory) PROTO((struct buffer *)); -{ - struct compress_buffer *n; - int zstatus; - - n = (struct compress_buffer *) xmalloc (sizeof *n); - memset (n, 0, sizeof *n); - - n->buf = buf; - - if (input) - zstatus = inflateInit (&n->zstr); - else - zstatus = deflateInit (&n->zstr, level); - if (zstatus != Z_OK) - compress_error (1, zstatus, &n->zstr, "compression initialization"); - - /* There may already be data buffered on BUF. For an output - buffer, this is OK, because these routines will just use the - buffer routines to append data to the (uncompressed) data - already on BUF. An input buffer expects to handle a single - buffer_data of buffered input to be uncompressed, so that is OK - provided there is only one buffer. At present that is all - there ever will be; if this changes, compress_buffer_input must - be modified to handle multiple input buffers. */ - assert (! input || buf->data == NULL || buf->data->next == NULL); - - return buf_initialize (input ? compress_buffer_input : NULL, - input ? NULL : compress_buffer_output, - input ? NULL : compress_buffer_flush, - compress_buffer_block, - (input - ? compress_buffer_shutdown_input - : compress_buffer_shutdown_output), - memory, - n); -} - -/* Input data from a compression buffer. */ - -static int -compress_buffer_input (closure, data, need, size, got) - void *closure; - char *data; - int need; - int size; - int *got; -{ - struct compress_buffer *cb = (struct compress_buffer *) closure; - struct buffer_data *bd; - - if (cb->buf->input == NULL) - abort (); - - /* We use a single buffer_data structure to buffer up data which - the z_stream structure won't use yet. We can safely store this - on cb->buf->data, because we never call the buffer routines on - cb->buf; we only call the buffer input routine, since that - gives us the semantics we want. As noted in - compress_buffer_initialize, the buffer_data structure may - already exist, and hold data which was already read and - buffered before the decompression began. */ - bd = cb->buf->data; - if (bd == NULL) - { - bd = ((struct buffer_data *) xmalloc (sizeof (struct buffer_data))); - if (bd == NULL) - return -2; - bd->text = (char *) xmalloc (BUFFER_DATA_SIZE); - if (bd->text == NULL) - { - free (bd); - return -2; - } - bd->bufp = bd->text; - bd->size = 0; - cb->buf->data = bd; - } - - cb->zstr.avail_out = size; - cb->zstr.next_out = (Bytef *) data; - - while (1) - { - int zstatus, sofar, status, nread; - - /* First try to inflate any data we already have buffered up. - This is useful even if we don't have any buffered data, - because there may be data buffered inside the z_stream - structure. */ - - cb->zstr.avail_in = bd->size; - cb->zstr.next_in = (Bytef *) bd->bufp; - - do - { - zstatus = inflate (&cb->zstr, Z_NO_FLUSH); - if (zstatus == Z_STREAM_END) - break; - if (zstatus != Z_OK && zstatus != Z_BUF_ERROR) - { - compress_error (0, zstatus, &cb->zstr, "inflate"); - return EIO; - } - } while (cb->zstr.avail_in > 0 - && cb->zstr.avail_out > 0); - - bd->size = cb->zstr.avail_in; - bd->bufp = (char *) cb->zstr.next_in; - - if (zstatus == Z_STREAM_END) - return -1; - - /* If we have obtained NEED bytes, then return, unless NEED is - zero and we haven't obtained anything at all. If NEED is - zero, we will keep reading from the underlying buffer until - we either can't read anything, or we have managed to - inflate at least one byte. */ - sofar = size - cb->zstr.avail_out; - if (sofar > 0 && sofar >= need) - break; - - /* All our buffered data should have been processed at this - point. */ - assert (bd->size == 0); - - /* This will work well in the server, because this call will - do an unblocked read and fetch all the available data. In - the client, this will read a single byte from the stdio - stream, which will cause us to call inflate once per byte. - It would be more efficient if we could make a call which - would fetch all the available bytes, and at least one byte. */ - - status = (*cb->buf->input) (cb->buf->closure, bd->text, - need > 0 ? 1 : 0, - BUFFER_DATA_SIZE, &nread); - if (status != 0) - return status; - - /* If we didn't read anything, then presumably the buffer is - in nonblocking mode, and we should just get out now with - whatever we've inflated. */ - if (nread == 0) - { - assert (need == 0); - break; - } - - bd->bufp = bd->text; - bd->size = nread; - } - - *got = size - cb->zstr.avail_out; - - return 0; -} - -/* Output data to a compression buffer. */ - -static int -compress_buffer_output (closure, data, have, wrote) - void *closure; - const char *data; - int have; - int *wrote; -{ - struct compress_buffer *cb = (struct compress_buffer *) closure; - - cb->zstr.avail_in = have; - cb->zstr.next_in = (unsigned char *) data; - - while (cb->zstr.avail_in > 0) - { - char buffer[BUFFER_DATA_SIZE]; - int zstatus; - - cb->zstr.avail_out = BUFFER_DATA_SIZE; - cb->zstr.next_out = (unsigned char *) buffer; - - zstatus = deflate (&cb->zstr, Z_NO_FLUSH); - if (zstatus != Z_OK) - { - compress_error (0, zstatus, &cb->zstr, "deflate"); - return EIO; - } - - if (cb->zstr.avail_out != BUFFER_DATA_SIZE) - buf_output (cb->buf, buffer, - BUFFER_DATA_SIZE - cb->zstr.avail_out); - } - - *wrote = have; - - /* We will only be here because buf_send_output was called on the - compression buffer. That means that we should now call - buf_send_output on the underlying buffer. */ - return buf_send_output (cb->buf); -} - -/* Flush a compression buffer. */ - -static int -compress_buffer_flush (closure) - void *closure; -{ - struct compress_buffer *cb = (struct compress_buffer *) closure; - - cb->zstr.avail_in = 0; - cb->zstr.next_in = NULL; - - while (1) - { - char buffer[BUFFER_DATA_SIZE]; - int zstatus; - - cb->zstr.avail_out = BUFFER_DATA_SIZE; - cb->zstr.next_out = (unsigned char *) buffer; - - zstatus = deflate (&cb->zstr, Z_SYNC_FLUSH); - - /* The deflate function will return Z_BUF_ERROR if it can't do - anything, which in this case means that all data has been - flushed. */ - if (zstatus == Z_BUF_ERROR) - break; - - if (zstatus != Z_OK) - { - compress_error (0, zstatus, &cb->zstr, "deflate flush"); - return EIO; - } - - if (cb->zstr.avail_out != BUFFER_DATA_SIZE) - buf_output (cb->buf, buffer, - BUFFER_DATA_SIZE - cb->zstr.avail_out); - - /* If the deflate function did not fill the output buffer, - then all data has been flushed. */ - if (cb->zstr.avail_out > 0) - break; - } - - /* Now flush the underlying buffer. Note that if the original - call to buf_flush passed 1 for the BLOCK argument, then the - buffer will already have been set into blocking mode, so we - should always pass 0 here. */ - return buf_flush (cb->buf, 0); -} - -/* The block routine for a compression buffer. */ - -static int -compress_buffer_block (closure, block) - void *closure; - int block; -{ - struct compress_buffer *cb = (struct compress_buffer *) closure; - - if (block) - return set_block (cb->buf); - else - return set_nonblock (cb->buf); -} - -/* Shut down an input buffer. */ - -static int -compress_buffer_shutdown_input (buf) - struct buffer *buf; -{ - struct compress_buffer *cb = (struct compress_buffer *) buf->closure; - int zstatus; - - /* Don't make any attempt to pick up trailing data since we are shutting - * down. If the client doesn't know we are shutting down, we might not - * see the EOF we are expecting. - */ - - zstatus = inflateEnd (&cb->zstr); - if (zstatus != Z_OK) - { - compress_error (0, zstatus, &cb->zstr, "inflateEnd"); - return EIO; - } - - return buf_shutdown (cb->buf); -} - -/* Shut down an output buffer. */ - -static int -compress_buffer_shutdown_output (buf) - struct buffer *buf; -{ - struct compress_buffer *cb = (struct compress_buffer *) buf->closure; - int zstatus, status; - - do - { - char buffer[BUFFER_DATA_SIZE]; - - cb->zstr.avail_out = BUFFER_DATA_SIZE; - cb->zstr.next_out = (unsigned char *) buffer; - - zstatus = deflate (&cb->zstr, Z_FINISH); - if (zstatus != Z_OK && zstatus != Z_STREAM_END) - { - compress_error (0, zstatus, &cb->zstr, "deflate finish"); - return EIO; - } - - if (cb->zstr.avail_out != BUFFER_DATA_SIZE) - buf_output (cb->buf, buffer, - BUFFER_DATA_SIZE - cb->zstr.avail_out); - } while (zstatus != Z_STREAM_END); - - zstatus = deflateEnd (&cb->zstr); - if (zstatus != Z_OK) - { - compress_error (0, zstatus, &cb->zstr, "deflateEnd"); - return EIO; - } - - status = buf_flush (cb->buf, 1); - if (status != 0) - return status; - - return buf_shutdown (cb->buf); -} - - - -/* Here is our librarified gzip implementation. It is very minimal - but attempts to be RFC1952 compliant. */ - -/* GZIP ID byte values */ -#define GZIP_ID1 31 -#define GZIP_ID2 139 - -/* Compression methods */ -#define GZIP_CDEFLATE 8 - -/* Flags */ -#define GZIP_FTEXT 1 -#define GZIP_FHCRC 2 -#define GZIP_FEXTRA 4 -#define GZIP_FNAME 8 -#define GZIP_FCOMMENT 16 - -/* BUF should contain SIZE bytes of gzipped data (RFC1952/RFC1951). - We are to uncompress the data and write the result to the file - descriptor FD. If something goes wrong, give a nonfatal error message - mentioning FULLNAME as the name of the file for FD. Return 1 if - it is an error we can't recover from. */ - -int -gunzip_and_write (fd, fullname, buf, size) - int fd; - char *fullname; - unsigned char *buf; - size_t size; -{ - size_t pos; - z_stream zstr; - int zstatus; - unsigned char outbuf[32768]; - unsigned long crc; - - if (size < 10) - { - error (0, 0, "gzipped data too small - lacks complete header"); - return 1; - } - if (buf[0] != GZIP_ID1 || buf[1] != GZIP_ID2) - { - error (0, 0, "gzipped data does not start with gzip identification"); - return 1; - } - if (buf[2] != GZIP_CDEFLATE) - { - error (0, 0, "only the deflate compression method is supported"); - return 1; - } - - /* Skip over the fixed header, and then skip any of the variable-length - fields. As we skip each field, we keep pos <= size. The checks - on positions and lengths are really checks for malformed or - incomplete gzip data. */ - pos = 10; - if (buf[3] & GZIP_FEXTRA) - { - if (pos + 2 >= size) - { - error (0, 0, "%s lacks proper gzip XLEN field", fullname); - return 1; - } - pos += buf[pos] + (buf[pos + 1] << 8) + 2; - if (pos > size) - { - error (0, 0, "%s lacks proper gzip \"extra field\"", fullname); - return 1; - } - - } - if (buf[3] & GZIP_FNAME) - { - unsigned char *p = memchr(buf + pos, '\0', size - pos); - if (p == NULL) - { - error (0, 0, "%s has bad gzip filename field", fullname); - return 1; - } - pos = p - buf + 1; - } - if (buf[3] & GZIP_FCOMMENT) - { - unsigned char *p = memchr(buf + pos, '\0', size - pos); - if (p == NULL) - { - error (0, 0, "%s has bad gzip comment field", fullname); - return 1; - } - pos = p - buf + 1; - } - if (buf[3] & GZIP_FHCRC) - { - pos += 2; - if (pos > size) - { - error (0, 0, "%s has bad gzip CRC16 field", fullname); - return 1; - } - } - - /* There could be no data to decompress - check and short circuit. */ - if (pos >= size) - { - error (0, 0, "gzip data incomplete for %s (no data)", fullname); - return 1; - } - - memset (&zstr, 0, sizeof zstr); - /* Passing a negative argument tells zlib not to look for a zlib - (RFC1950) header. This is an undocumented feature; I suppose if - we wanted to be anal we could synthesize a header instead, - but why bother? */ - zstatus = inflateInit2 (&zstr, -15); - - if (zstatus != Z_OK) - compress_error (1, zstatus, &zstr, fullname); - - /* I don't see why we should have to include the 8 byte trailer in - avail_in. But I see that zlib/gzio.c does, and it seemed to fix - a fairly rare bug in which we'd get a Z_BUF_ERROR for no obvious - reason. */ - zstr.avail_in = size - pos; - zstr.next_in = buf + pos; - - crc = crc32 (0, NULL, 0); - - do - { - zstr.avail_out = sizeof (outbuf); - zstr.next_out = outbuf; - zstatus = inflate (&zstr, Z_NO_FLUSH); - if (zstatus != Z_STREAM_END && zstatus != Z_OK) - { - compress_error (0, zstatus, &zstr, fullname); - return 1; - } - if (write (fd, outbuf, sizeof (outbuf) - zstr.avail_out) < 0) - { - error (0, errno, "writing decompressed file %s", fullname); - return 1; - } - crc = crc32 (crc, outbuf, sizeof (outbuf) - zstr.avail_out); - } while (zstatus != Z_STREAM_END); - zstatus = inflateEnd (&zstr); - if (zstatus != Z_OK) - compress_error (0, zstatus, &zstr, fullname); - - /* Check that there is still 8 trailer bytes remaining (CRC32 - and ISIZE). Check total decomp. data, plus header len (pos) - against input buffer total size. */ - pos += zstr.total_in; - if (size - pos != 8) - { - error (0, 0, "gzip data incomplete for %s (no trailer)", fullname); - return 1; - } - - if (crc != ((unsigned long)buf[pos] - + ((unsigned long)buf[pos + 1] << 8) - + ((unsigned long)buf[pos + 2] << 16) - + ((unsigned long)buf[pos + 3] << 24))) - { - error (0, 0, "CRC error uncompressing %s", fullname); - return 1; - } - - if (zstr.total_out != ((unsigned long)buf[pos + 4] - + ((unsigned long)buf[pos + 5] << 8) - + ((unsigned long)buf[pos + 6] << 16) - + ((unsigned long)buf[pos + 7] << 24))) - { - error (0, 0, "invalid length uncompressing %s", fullname); - return 1; - } - - return 0; -} - -/* Read all of FD and put the gzipped data (RFC1952/RFC1951) into *BUF, - replacing previous contents of *BUF. *BUF is xmalloc'd and *SIZE is - its allocated size. Put the actual number of bytes of data in - *LEN. If something goes wrong, give a nonfatal error mentioning - FULLNAME as the name of the file for FD, and return 1 if we can't - recover from it). LEVEL is the compression level (1-9). */ - -int -read_and_gzip (fd, fullname, buf, size, len, level) - int fd; - const char *fullname; - unsigned char **buf; - size_t *size; - size_t *len; - int level; -{ - z_stream zstr; - int zstatus; - unsigned char inbuf[8192]; - int nread; - unsigned long crc; - - if (*size < 1024) - { - unsigned char *newbuf; - - *size = 1024; - newbuf = xrealloc (*buf, *size); - if (newbuf == NULL) - { - error (0, 0, "out of memory"); - return 1; - } - *buf = newbuf; - } - (*buf)[0] = GZIP_ID1; - (*buf)[1] = GZIP_ID2; - (*buf)[2] = GZIP_CDEFLATE; - (*buf)[3] = 0; - (*buf)[4] = (*buf)[5] = (*buf)[6] = (*buf)[7] = 0; - /* Could set this based on level, but why bother? */ - (*buf)[8] = 0; - (*buf)[9] = 255; - - memset (&zstr, 0, sizeof zstr); - zstatus = deflateInit2 (&zstr, level, Z_DEFLATED, -15, 8, - Z_DEFAULT_STRATEGY); - crc = crc32 (0, NULL, 0); - if (zstatus != Z_OK) - { - compress_error (0, zstatus, &zstr, fullname); - return 1; - } - - /* Adjust for 10-byte output header (filled in above) */ - zstr.total_out = 10; - zstr.avail_out = *size - 10; - zstr.next_out = *buf + 10; - - while (1) - { - int finish = 0; - - nread = read (fd, inbuf, sizeof inbuf); - if (nread < 0) - { - error (0, errno, "cannot read %s", fullname); - return 1; - } - else if (nread == 0) - /* End of file. */ - finish = 1; - crc = crc32 (crc, inbuf, nread); - zstr.next_in = inbuf; - zstr.avail_in = nread; - - do - { - /* I don't see this documented anywhere, but deflate seems - to tend to dump core sometimes if we pass it Z_FINISH and - a small (e.g. 2147 byte) avail_out. So we insist on at - least 4096 bytes (that is what zlib/gzio.c uses). */ - - if (zstr.avail_out < 4096) - { - unsigned char *newbuf; - - assert(zstr.avail_out + zstr.total_out == *size); - assert(zstr.next_out == *buf + zstr.total_out); - *size *= 2; - newbuf = xrealloc (*buf, *size); - if (newbuf == NULL) - { - error (0, 0, "out of memory"); - return 1; - } - *buf = newbuf; - zstr.next_out = *buf + zstr.total_out; - zstr.avail_out = *size - zstr.total_out; - assert(zstr.avail_out + zstr.total_out == *size); - assert(zstr.next_out == *buf + zstr.total_out); - } - - zstatus = deflate (&zstr, finish ? Z_FINISH : 0); - if (zstatus == Z_STREAM_END) - goto done; - else if (zstatus != Z_OK) - compress_error (0, zstatus, &zstr, fullname); - } while (zstr.avail_out == 0); - } - done: - /* Need to add the CRC information (8 bytes) - to the end of the gzip'd output. - Ensure there is enough space in the output buffer - to do so. */ - if (zstr.avail_out < 8) - { - unsigned char *newbuf; - - assert(zstr.avail_out + zstr.total_out == *size); - assert(zstr.next_out == *buf + zstr.total_out); - *size += 8 - zstr.avail_out; - newbuf = realloc (*buf, *size); - if (newbuf == NULL) - { - error (0, 0, "out of memory"); - return 1; - } - *buf = newbuf; - zstr.next_out = *buf + zstr.total_out; - zstr.avail_out = *size - zstr.total_out; - assert(zstr.avail_out + zstr.total_out == *size); - assert(zstr.next_out == *buf + zstr.total_out); - } - *zstr.next_out++ = (unsigned char)(crc & 0xff); - *zstr.next_out++ = (unsigned char)((crc >> 8) & 0xff); - *zstr.next_out++ = (unsigned char)((crc >> 16) & 0xff); - *zstr.next_out++ = (unsigned char)((crc >> 24) & 0xff); - - *zstr.next_out++ = (unsigned char)(zstr.total_in & 0xff); - *zstr.next_out++ = (unsigned char)((zstr.total_in >> 8) & 0xff); - *zstr.next_out++ = (unsigned char)((zstr.total_in >> 16) & 0xff); - *zstr.next_out++ = (unsigned char)((zstr.total_in >> 24) & 0xff); - - zstr.total_out += 8; - zstr.avail_out -= 8; - assert(zstr.avail_out + zstr.total_out == *size); - assert(zstr.next_out == *buf + zstr.total_out); - - *len = zstr.total_out; - - zstatus = deflateEnd (&zstr); - if (zstatus != Z_OK) - compress_error (0, zstatus, &zstr, fullname); - - return 0; -} -#endif /* defined (SERVER_SUPPORT) || defined (CLIENT_SUPPORT) */ |
