From 2473391971b10ab9fdec66714d25d2ba357a3ac8 Mon Sep 17 00:00:00 2001 From: Wayne Davison Date: Fri, 4 Jul 2003 07:47:09 +0000 Subject: [PATCH] Improved upon my last patch to make it clearer and cleaner. --- token.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/token.c b/token.c index ed30c3f2..0b3aa999 100644 --- a/token.c +++ b/token.c @@ -127,6 +127,12 @@ static void simple_send_token(int f,int token, #define MAX_DATA_COUNT 16383 /* fit 14 bit count into 2 bytes with flags */ +/* zlib.h says that if we want to be able to compress something in a single + * call, avail_out must be at least 0.1% larger than avail_in plus 12 bytes. + * We'll add in 0.1%+16, just to be safe (and we'll avoid floating point, + * to ensure that this is a compile-time value). */ +#define AVAIL_OUT_SIZE(avail_in_size) ((avail_in_size)*1001/1000+16) + /* For coding runs of tokens */ static int last_token = -1; static int run_start; @@ -137,7 +143,14 @@ static z_stream tx_strm; /* Output buffer */ static char *obuf; -static int obuf_size; + +/* We want obuf to be able to hold both MAX_DATA_COUNT+2 bytes as well as + * AVAIL_OUT_SIZE(CHUNK_SIZE) bytes, so make sure that it's large enough. */ +#if MAX_DATA_COUNT+2 > AVAIL_OUT_SIZE(CHUNK_SIZE) +#define OBUF_SIZE (MAX_DATA_COUNT+2) +#else +#define OBUF_SIZE AVAIL_OUT_SIZE(CHUNK_SIZE) +#endif /* Send a deflated token */ static void @@ -161,12 +174,7 @@ send_deflated_token(int f, int token, rprintf(FERROR, "compression init failed\n"); exit_cleanup(RERR_STREAMIO); } -#if MAX_DATA_COUNT+2 > CHUNK_SIZE+128 /* this shouldn't ever happen... */ - obuf_size = MAX_DATA_COUNT+2; -#else - obuf_size = CHUNK_SIZE+128; -#endif - if ((obuf = malloc(obuf_size)) == NULL) + if ((obuf = malloc(OBUF_SIZE)) == NULL) out_of_memory("send_deflated_token"); init_done = 1; } else @@ -286,7 +294,7 @@ send_deflated_token(int f, int token, 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 = obuf_size; + tx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE); 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", -- 2.34.1