Update to use the new zlib-1.1.2 code.

The compressed token code now handles the null (-2)
token from the match logic.

Makefile.in

@@ -20,11 +20,14 @@ SHELL=/bin/sh
 .SUFFIXES:
 .SUFFIXES: .c .o
 
-LIBOBJ=lib/getopt.o lib/fnmatch.o lib/zlib.o lib/compat.o
+LIBOBJ=lib/getopt.o lib/fnmatch.o lib/compat.o
+ZLIBOBJ=zlib/deflate.o zlib/infblock.o zlib/infcodes.o zlib/inffast.o \
+	zlib/inflate.o zlib/inftrees.o zlib/infutil.o zlib/trees.o \
+	zlib/zutil.o zlib/adler32.o
 OBJS1=rsync.o exclude.o util.o md4.o main.o checksum.o match.o syscall.o log.o
 OBJS2=options.o flist.o io.o compat.o hlink.o token.o uidlist.o socket.o 
 DAEMON_OBJ = params.o loadparm.o clientserver.o access.o connection.o authenticate.o
-OBJS=$(OBJS1) $(OBJS2) $(DAEMON_OBJ) $(LIBOBJ)
+OBJS=$(OBJS1) $(OBJS2) $(DAEMON_OBJ) $(LIBOBJ) $(ZLIBOBJ)
 
 # note that the -I. is needed to handle config.h when using VPATH
 .c.o:

configure.in

@@ -118,3 +118,4 @@ fi])
 
 
 AC_OUTPUT(Makefile lib/dummy)
+AC_OUTPUT(Makefile zlib/dummy)

match.c

@@ -214,21 +214,15 @@ static void hash_search(int f,struct sum_struct *s,
 			--k;
 		}
 
-		if (!do_compression) {
-			/* By matching early we avoid re-reading the
-			   data 3 times in the case where a token
-			   match comes a long way after last
-			   match. The 3 reads are caused by the
-			   running match, the checksum update and the
-			   literal send.
-
-			   we don't enable this for the compressed
-			   case yet as the deflated token code can't
-			   handle it. Paul is working on it */
-			if (offset-last_match >= CHUNK_SIZE+s->n && 
-			    (end-offset > CHUNK_SIZE)) {
-				matched(f,s,buf,offset - s->n, -2);
-			}
+		/* By matching early we avoid re-reading the
+		   data 3 times in the case where a token
+		   match comes a long way after last
+		   match. The 3 reads are caused by the
+		   running match, the checksum update and the
+		   literal send. */
+		if (offset-last_match >= CHUNK_SIZE+s->n && 
+		    (end-offset > CHUNK_SIZE)) {
+			matched(f,s,buf,offset - s->n, -2);
 		}
 	} while (++offset < end);
 	

token.c

@@ -18,7 +18,7 @@
 */
 
 #include "rsync.h"
-#include "lib/zlib.h"
+#include "zlib/zlib.h"
 
 extern int do_compression;
 
@@ -69,19 +69,6 @@ static void simple_send_token(int f,int token,
 }
 
 
-/* Memory allocation/freeing routines, called by zlib stuff. */
-static void *
-z_alloc(void *opaque, uInt items, uInt size)
-{
-    return malloc(items * size);
-}
-
-static void
-z_free(void *opaque, void *adrs, uInt nbytes)
-{
-    free(adrs);
-}
-
 /* Flag bytes in compressed stream are encoded as follows: */
 #define END_FLAG	0	/* that's all folks */
 #define TOKEN_LONG	0x20	/* followed by 32-bit token number */
@@ -108,100 +95,129 @@ static void
 send_deflated_token(int f, int token,
 		    struct map_struct *buf, OFF_T offset, int nb, int toklen)
 {
-    int n, r;
-    static int init_done;
+	int n, r;
+	static int init_done, flush_pending;
 
-    if (last_token == -1) {
-	/* initialization */
-	if (!init_done) {
-	    tx_strm.next_in = NULL;
-	    tx_strm.zalloc = z_alloc;
-	    tx_strm.zfree = z_free;
-	    if (deflateInit2(&tx_strm, Z_DEFAULT_COMPRESSION, 8,
-			     -15, 8, Z_DEFAULT_STRATEGY) != Z_OK) {
-		rprintf(FERROR, "compression init failed\n");
-		exit_cleanup(1);
-	    }
-	    if ((obuf = malloc(MAX_DATA_COUNT+2)) == NULL)
-		out_of_memory("send_deflated_token");
-	    init_done = 1;
-	} else
-	    deflateReset(&tx_strm);
-	run_start = token;
-	last_run_end = 0;
+	if (last_token == -1) {
+		/* initialization */
+		if (!init_done) {
+			tx_strm.next_in = NULL;
+			tx_strm.zalloc = NULL;
+			tx_strm.zfree = NULL;
+			if (deflateInit2(&tx_strm, Z_DEFAULT_COMPRESSION,
+					 Z_DEFLATED, -15, 8,
+					 Z_DEFAULT_STRATEGY) != Z_OK) {
+				rprintf(FERROR, "compression init failed\n");
+				exit_cleanup(1);
+			}
+			if ((obuf = malloc(MAX_DATA_COUNT+2)) == NULL)
+				out_of_memory("send_deflated_token");
+			init_done = 1;
+		} else
+			deflateReset(&tx_strm);
+		last_run_end = 0;
+		run_start = token;
+		flush_pending = 0;
 
-    } else if (nb != 0 || token != last_token + 1
-	       || token >= run_start + 65536) {
-	/* output previous run */
-	r = run_start - last_run_end;
-	n = last_token - run_start;
-	if (r >= 0 && r <= 63) {
-	    write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
-	} else {
-	    write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
-	    write_int(f, run_start);
-	}
-	if (n != 0) {
-	    write_byte(f, n);
-	    write_byte(f, n >> 8);
-	}
-	last_run_end = last_token;
-	run_start = token;
-    }
+	} else if (last_token == -2) {
+		run_start = token;
 
-    last_token = token;
-
-    if (nb != 0) {
-	/* deflate the data starting at offset */
-	tx_strm.avail_in = 0;
-	tx_strm.avail_out = 0;
-	do {
-	    if (tx_strm.avail_in == 0 && nb != 0) {
-		/* give it some more input */
-		n = MIN(nb, CHUNK_SIZE);
-		tx_strm.next_in = (Bytef *)map_ptr(buf, offset, n);
-		tx_strm.avail_in = n;
-		nb -= n;
-		offset += n;
-	    }
-	    if (tx_strm.avail_out == 0) {
-		tx_strm.next_out = (Bytef *)(obuf + 2);
-		tx_strm.avail_out = MAX_DATA_COUNT;
-	    }
-	    r = deflate(&tx_strm, nb? Z_NO_FLUSH: Z_PACKET_FLUSH);
-	    if (r != Z_OK) {
-		rprintf(FERROR, "deflate returned %d\n", r);
-		exit_cleanup(1);
-	    }
-	    if (nb == 0 || tx_strm.avail_out == 0) {
-		n = MAX_DATA_COUNT - tx_strm.avail_out;
-		if (n > 0) {
-		    obuf[0] = DEFLATED_DATA + (n >> 8);
-		    obuf[1] = n;
-		    write_buf(f, obuf, n+2);
+	} else if (nb != 0 || token != last_token + 1
+		   || token >= run_start + 65536) {
+		/* output previous run */
+		r = run_start - last_run_end;
+		n = last_token - run_start;
+		if (r >= 0 && r <= 63) {
+			write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
+		} else {
+			write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
+			write_int(f, run_start);
 		}
-	    }
-	} while (nb != 0 || tx_strm.avail_out == 0);
-    }
-
-    if (token != -1) {
-	/* add the data in the current block to the compressor's
-	   history and hash table */
-	tx_strm.next_in = (Bytef *)map_ptr(buf, offset, toklen);
-	tx_strm.avail_in = toklen;
-	tx_strm.next_out = NULL;
-	tx_strm.avail_out = 2 * toklen;
-	r = deflate(&tx_strm, Z_INSERT_ONLY);
-	if (r != Z_OK || tx_strm.avail_in != 0) {
-	    rprintf(FERROR, "deflate on token returned %d (%d bytes left)\n",
-		    r, tx_strm.avail_in);
-	    exit_cleanup(1);
+		if (n != 0) {
+			write_byte(f, n);
+			write_byte(f, n >> 8);
+		}
+		last_run_end = last_token;
+		run_start = token;
 	}
 
-    } else {
-	/* end of file - clean up */
-	write_byte(f, END_FLAG);
-    }
+	last_token = token;
+
+	if (nb != 0 || flush_pending) {
+		/* deflate the data starting at offset */
+		int flush = Z_NO_FLUSH;
+		tx_strm.avail_in = 0;
+		tx_strm.avail_out = 0;
+		do {
+			if (tx_strm.avail_in == 0 && nb != 0) {
+				/* give it some more input */
+				n = MIN(nb, CHUNK_SIZE);
+				tx_strm.next_in = (Bytef *)
+					map_ptr(buf, offset, n);
+				tx_strm.avail_in = n;
+				nb -= n;
+				offset += n;
+			}
+			if (tx_strm.avail_out == 0) {
+				tx_strm.next_out = (Bytef *)(obuf + 2);
+				tx_strm.avail_out = MAX_DATA_COUNT;
+				if (flush != Z_NO_FLUSH) {
+					/*
+					 * We left the last 4 bytes in the
+					 * buffer, in case they are the
+					 * last 4.  Move them to the front.
+					 */
+					memcpy(tx_strm.next_out,
+					       obuf+MAX_DATA_COUNT-2, 4);
+					tx_strm.next_out += 4;
+					tx_strm.avail_out -= 4;
+				}
+			}
+			if (nb == 0 && token != -2)
+				flush = Z_SYNC_FLUSH;
+			r = deflate(&tx_strm, flush);
+			if (r != Z_OK) {
+				rprintf(FERROR, "deflate returned %d\n", r);
+				exit_cleanup(1);
+			}
+			if (nb == 0 || tx_strm.avail_out == 0) {
+				n = MAX_DATA_COUNT - tx_strm.avail_out;
+				if (flush != Z_NO_FLUSH) {
+					/*
+					 * We have to trim off the last 4
+					 * bytes of output when flushing
+					 * (they are just 0, 0, ff, ff).
+					 */
+					n -= 4;
+				}
+				if (n > 0) {
+					obuf[0] = DEFLATED_DATA + (n >> 8);
+					obuf[1] = n;
+					write_buf(f, obuf, n+2);
+				}
+			}
+		} while (nb != 0 || tx_strm.avail_out == 0);
+		flush_pending = token == -2;
+	}
+
+	if (token == -1) {
+		/* end of file - clean up */
+		write_byte(f, END_FLAG);
+
+	} else if (token != -2) {
+		/* add the data in the current block to the compressor's
+		   history and hash table */
+		tx_strm.next_in = (Bytef *) map_ptr(buf, offset, toklen);
+		tx_strm.avail_in = toklen;
+		tx_strm.next_out = (Bytef *) obuf;
+		tx_strm.avail_out = MAX_DATA_COUNT;
+		r = deflate(&tx_strm, Z_INSERT_ONLY);
+		if (r != Z_OK || tx_strm.avail_in != 0) {
+			rprintf(FERROR, "deflate on token returned %d (%d bytes left)\n",
+				r, tx_strm.avail_in);
+			exit_cleanup(1);
+		}
+	}
 }
 
 
@@ -221,113 +237,129 @@ static int rx_run;
 static int
 recv_deflated_token(int f, char **data)
 {
-    int n, r, flag;
-    static int init_done;
-    static int saved_flag;
+	int n, r, flag;
+	static int init_done;
+	static int saved_flag;
 
-    for (;;) {
-	switch (recv_state) {
-	case r_init:
-	    if (!init_done) {
-		rx_strm.next_out = NULL;
-		rx_strm.zalloc = z_alloc;
-		rx_strm.zfree = z_free;
-		if (inflateInit2(&rx_strm, -15) != Z_OK) {
-		    rprintf(FERROR, "inflate init failed\n");
-		    exit_cleanup(1);
-		}
-		if ((cbuf = malloc(MAX_DATA_COUNT)) == NULL
-		    || (dbuf = malloc(CHUNK_SIZE)) == NULL)
-		    out_of_memory("recv_deflated_token");
-		init_done = 1;
-	    } else {
-		inflateReset(&rx_strm);
-	    }
-	    recv_state = r_idle;
-	    rx_token = 0;
-	    break;
-	    
-	case r_idle:
-	case r_inflated:
-	    if (saved_flag) {
-		flag = saved_flag & 0xff;
-		saved_flag = 0;
-	    } else
-		flag = read_byte(f);
-	    if ((flag & 0xC0) == DEFLATED_DATA) {
-		n = ((flag & 0x3f) << 8) + read_byte(f);
-		read_buf(f, cbuf, n);
-		rx_strm.next_in = (Bytef *)cbuf;
-		rx_strm.avail_in = n;
-		recv_state = r_inflating;
-		break;
-	    }
-	    if (recv_state == r_inflated) {
-		/* check previous inflated stuff ended correctly */
-		rx_strm.avail_in = 0;
-		rx_strm.next_out = (Bytef *)dbuf;
-		rx_strm.avail_out = CHUNK_SIZE;
-		r = inflate(&rx_strm, Z_PACKET_FLUSH);
-		n = CHUNK_SIZE - rx_strm.avail_out;
-		if (r != Z_OK) {
-		    rprintf(FERROR, "inflate flush returned %d (%d bytes)\n",
-			    r, n);
-		    exit_cleanup(1);
-		}
-		if (n != 0) {
-		    /* have to return some more data and
-		       save the flag for later. */
-		    saved_flag = flag + 0x10000;
-		    if (rx_strm.avail_out != 0)
+	for (;;) {
+		switch (recv_state) {
+		case r_init:
+			if (!init_done) {
+				rx_strm.next_out = NULL;
+				rx_strm.zalloc = NULL;
+				rx_strm.zfree = NULL;
+				if (inflateInit2(&rx_strm, -15) != Z_OK) {
+					rprintf(FERROR, "inflate init failed\n");
+					exit_cleanup(1);
+				}
+				if ((cbuf = malloc(MAX_DATA_COUNT)) == NULL
+				    || (dbuf = malloc(CHUNK_SIZE)) == NULL)
+					out_of_memory("recv_deflated_token");
+				init_done = 1;
+			} else {
+				inflateReset(&rx_strm);
+			}
 			recv_state = r_idle;
-		    *data = dbuf;
-		    return n;
+			rx_token = 0;
+			break;
+
+		case r_idle:
+		case r_inflated:
+			if (saved_flag) {
+				flag = saved_flag & 0xff;
+				saved_flag = 0;
+			} else
+				flag = read_byte(f);
+			if ((flag & 0xC0) == DEFLATED_DATA) {
+				n = ((flag & 0x3f) << 8) + read_byte(f);
+				read_buf(f, cbuf, n);
+				rx_strm.next_in = (Bytef *)cbuf;
+				rx_strm.avail_in = n;
+				recv_state = r_inflating;
+				break;
+			}
+			if (recv_state == r_inflated) {
+				/* check previous inflated stuff ended correctly */
+				rx_strm.avail_in = 0;
+				rx_strm.next_out = (Bytef *)dbuf;
+				rx_strm.avail_out = CHUNK_SIZE;
+				r = inflate(&rx_strm, Z_SYNC_FLUSH);
+				n = CHUNK_SIZE - rx_strm.avail_out;
+				/*
+				 * Z_BUF_ERROR just means no progress was
+				 * made, i.e. the decompressor didn't have
+				 * any pending output for us.
+				 */
+				if (r != Z_OK && r != Z_BUF_ERROR) {
+					rprintf(FERROR, "inflate flush returned %d (%d bytes)\n",
+						r, n);
+					exit_cleanup(1);
+				}
+				if (n != 0 && r != Z_BUF_ERROR) {
+					/* have to return some more data and
+					   save the flag for later. */
+					saved_flag = flag + 0x10000;
+					*data = dbuf;
+					return n;
+				}
+				/*
+				 * At this point the decompressor should
+				 * be expecting to see the 0, 0, ff, ff bytes.
+				 */
+				if (!inflateSyncPoint(&rx_strm)) {
+					rprintf(FERROR, "decompressor lost sync!\n");
+					exit_cleanup(1);
+				}
+				rx_strm.avail_in = 4;
+				rx_strm.next_in = (Bytef *)cbuf;
+				cbuf[0] = cbuf[1] = 0;
+				cbuf[2] = cbuf[3] = 0xff;
+				inflate(&rx_strm, Z_SYNC_FLUSH);
+				recv_state = r_idle;
+			}
+			if (flag == END_FLAG) {
+				/* that's all folks */
+				recv_state = r_init;
+				return 0;
+			}
+
+			/* here we have a token of some kind */
+			if (flag & TOKEN_REL) {
+				rx_token += flag & 0x3f;
+				flag >>= 6;
+			} else
+				rx_token = read_int(f);
+			if (flag & 1) {
+				rx_run = read_byte(f);
+				rx_run += read_byte(f) << 8;
+				recv_state = r_running;
+			}
+			return -1 - rx_token;
+
+		case r_inflating:
+			rx_strm.next_out = (Bytef *)dbuf;
+			rx_strm.avail_out = CHUNK_SIZE;
+			r = inflate(&rx_strm, Z_NO_FLUSH);
+			n = CHUNK_SIZE - rx_strm.avail_out;
+			if (r != Z_OK) {
+				rprintf(FERROR, "inflate returned %d (%d bytes)\n", r, n);
+				exit_cleanup(1);
+			}
+			if (rx_strm.avail_in == 0)
+				recv_state = r_inflated;
+			if (n != 0) {
+				*data = dbuf;
+				return n;
+			}
+			break;
+
+		case r_running:
+			++rx_token;
+			if (--rx_run == 0)
+				recv_state = r_idle;
+			return -1 - rx_token;
 		}
-		recv_state = r_idle;
-	    }
-	    if (flag == END_FLAG) {
-		/* that's all folks */
-		recv_state = r_init;
-		return 0;
-	    }
-
-	    /* here we have a token of some kind */
-	    if (flag & TOKEN_REL) {
-		rx_token += flag & 0x3f;
-		flag >>= 6;
-	    } else
-		rx_token = read_int(f);
-	    if (flag & 1) {
-		rx_run = read_byte(f);
-		rx_run += read_byte(f) << 8;
-		recv_state = r_running;
-	    }
-	    return -1 - rx_token;
-
-	case r_inflating:
-	    rx_strm.next_out = (Bytef *)dbuf;
-	    rx_strm.avail_out = CHUNK_SIZE;
-	    r = inflate(&rx_strm, Z_NO_FLUSH);
-	    n = CHUNK_SIZE - rx_strm.avail_out;
-	    if (r != Z_OK) {
-		rprintf(FERROR, "inflate returned %d (%d bytes)\n", r, n);
-		exit_cleanup(1);
-	    }
-	    if (rx_strm.avail_in == 0)
-		recv_state = r_inflated;
-	    if (n != 0) {
-		*data = dbuf;
-		return n;
-	    }
-	    break;
-
-	case r_running:
-	    ++rx_token;
-	    if (--rx_run == 0)
-		recv_state = r_idle;
-	    return -1 - rx_token;
 	}
-    }
 }
 
 /*
@@ -337,15 +369,40 @@ recv_deflated_token(int f, char **data)
 void
 see_deflate_token(char *buf, int len)
 {
-    int r;
+	int r, blklen;
+	unsigned char hdr[5];
 
-    rx_strm.next_in = (Bytef *)buf;
-    rx_strm.avail_in = len;
-    r = inflateIncomp(&rx_strm);
-    if (r != Z_OK) {
-	rprintf(FERROR, "inflateIncomp returned %d\n", r);
-	exit_cleanup(1);
-    }
+	rx_strm.avail_in = 0;
+	blklen = 0;
+	hdr[0] = 0;
+	do {
+		if (rx_strm.avail_in == 0 && len != 0) {
+			if (blklen == 0) {
+				/* Give it a fake stored-block header. */
+				rx_strm.next_in = (Bytef *)hdr;
+				rx_strm.avail_in = 5;
+				blklen = len;
+				if (blklen > 0xffff)
+					blklen = 0xffff;
+				hdr[1] = blklen;
+				hdr[2] = blklen >> 8;
+				hdr[3] = ~hdr[1];
+				hdr[4] = ~hdr[2];
+			} else {
+				rx_strm.next_in = (Bytef *)buf;
+				rx_strm.avail_in = blklen;
+				len -= blklen;
+				blklen = 0;
+			}
+		}
+		rx_strm.next_out = (Bytef *)dbuf;
+		rx_strm.avail_out = CHUNK_SIZE;
+		r = inflate(&rx_strm, Z_SYNC_FLUSH);
+		if (r != Z_OK) {
+			rprintf(FERROR, "inflate (token) returned %d\n", r);
+			exit_cleanup(1);
+		}
+	} while (len || rx_strm.avail_out == 0);
 }
 
 /*
@@ -356,11 +413,11 @@ see_deflate_token(char *buf, int len)
 void send_token(int f,int token,struct map_struct *buf,OFF_T offset,
 		int n,int toklen)
 {
-  if (!do_compression) {
-    simple_send_token(f,token,buf,offset,n);
-  } else {
-    send_deflated_token(f, token, buf, offset, n, toklen);
-  }
+	if (!do_compression) {
+		simple_send_token(f,token,buf,offset,n);
+	} else {
+		send_deflated_token(f, token, buf, offset, n, toklen);
+	}
 }
 
 
@@ -372,14 +429,14 @@ void send_token(int f,int token,struct map_struct *buf,OFF_T offset,
  */
 int recv_token(int f,char **data)
 {
-  int tok;
+	int tok;
 
-  if (!do_compression) {
-    tok = simple_recv_token(f,data);
-  } else {
-    tok = recv_deflated_token(f, data);
-  }
-  return tok;
+	if (!do_compression) {
+		tok = simple_recv_token(f,data);
+	} else {
+		tok = recv_deflated_token(f, data);
+	}
+	return tok;
 }
 
 /*
@@ -387,6 +444,6 @@ int recv_token(int f,char **data)
  */
 void see_token(char *data, int toklen)
 {
-    if (do_compression)
-	see_deflate_token(data, toklen);
+	if (do_compression)
+		see_deflate_token(data, toklen);
 }

zlib/deflate.c

@@ -80,7 +80,7 @@ local block_state deflate_slow   OF((deflate_state *s, int flush));
 local void lm_init        OF((deflate_state *s));
 local void putShortMSB    OF((deflate_state *s, uInt b));
 local void flush_pending  OF((z_streamp strm));
-local int read_buf        OF((z_streamp strm, Bytef *buf, unsigned size));
+local int dread_buf        OF((z_streamp strm, Bytef *buf, unsigned size));
 #ifdef ASMV
       void match_init OF((void)); /* asm code initialization */
       uInt longest_match  OF((deflate_state *s, IPos cur_match));
@@ -411,7 +411,7 @@ local void putShortMSB (s, b)
  * Flush as much pending output as possible. All deflate() output goes
  * through this function so some applications may wish to modify it
  * to avoid allocating a large strm->next_out buffer and copying into it.
- * (See also read_buf()).
+ * (See also dread_buf()).
  */
 local void flush_pending(strm)
     z_streamp strm;
@@ -441,7 +441,7 @@ int ZEXPORT deflate (strm, flush)
     deflate_state *s;
 
     if (strm == Z_NULL || strm->state == Z_NULL ||
-	flush > Z_FINISH || flush < 0) {
+	flush > Z_INSERT_ONLY || flush < 0) {
         return Z_STREAM_ERROR;
     }
     s = strm->state;
@@ -657,7 +657,7 @@ int ZEXPORT deflateCopy (dest, source)
  * allocating a large strm->next_in buffer and copying from it.
  * (See also flush_pending()).
  */
-local int read_buf(strm, buf, size)
+local int dread_buf(strm, buf, size)
     z_streamp strm;
     Bytef *buf;
     unsigned size;
@@ -1028,7 +1028,7 @@ local void fill_window(s)
          */
         Assert(more >= 2, "more < 2");
 
-        n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more);
+        n = dread_buf(s->strm, s->window + s->strstart + s->lookahead, more);
         s->lookahead += n;
 
         /* Initialize the hash value now that we have some input: */
@@ -1162,6 +1162,12 @@ local block_state deflate_fast(s, flush)
             INSERT_STRING(s, s->strstart, hash_head);
         }
 
+	if (flush == Z_INSERT_ONLY) {
+	    s->strstart++;
+	    s->lookahead--;
+	    continue;
+	}
+
         /* Find the longest match, discarding those <= prev_length.
          * At this point we have always match_length < MIN_MATCH
          */
@@ -1221,6 +1227,10 @@ local block_state deflate_fast(s, flush)
         }
         if (bflush) FLUSH_BLOCK(s, 0);
     }
+    if (flush == Z_INSERT_ONLY) {
+	s->block_start = s->strstart;
+	return need_more;
+    }
     FLUSH_BLOCK(s, flush == Z_FINISH);
     return flush == Z_FINISH ? finish_done : block_done;
 }
@@ -1259,6 +1269,12 @@ local block_state deflate_slow(s, flush)
             INSERT_STRING(s, s->strstart, hash_head);
         }
 
+	if (flush == Z_INSERT_ONLY) {
+	    s->strstart++;
+	    s->lookahead--;
+	    continue;
+	}
+
         /* Find the longest match, discarding those <= prev_length.
          */
         s->prev_length = s->match_length, s->prev_match = s->match_start;
@@ -1337,6 +1353,10 @@ local block_state deflate_slow(s, flush)
             s->lookahead--;
         }
     }
+    if (flush == Z_INSERT_ONLY) {
+	s->block_start = s->strstart;
+	return need_more;
+    }
     Assert (flush != Z_NO_FLUSH, "no flush?");
     if (s->match_available) {
         Tracevv((stderr,"%c", s->window[s->strstart-1]));

zlib/zlib.h

@@ -127,6 +127,7 @@ typedef z_stream FAR *z_streamp;
 #define Z_SYNC_FLUSH    2
 #define Z_FULL_FLUSH    3
 #define Z_FINISH        4
+#define Z_INSERT_ONLY	5
 /* Allowed flush values; see deflate() below for details */
 
 #define Z_OK            0

zlib/zutil.h

@@ -13,8 +13,10 @@
 #ifndef _Z_UTIL_H
 #define _Z_UTIL_H
 
+#include "../rsync.h"
 #include "zlib.h"
 
+#if 0
 #ifdef STDC
 #  include <stddef.h>
 #  include <string.h>
@@ -25,6 +27,7 @@
 #else
 #   include <errno.h>
 #endif
+#endif
 
 #ifndef local
 #  define local static