From: markus schnalke <meillo@marmaro.de>
Date: Thu, 22 Mar 2012 20:27:53 +0000 (+0100)
Subject: scansbr: Removed the ``performance hack'' for inc as it wasn't faster.
X-Git-Tag: mmh-thesis-end~229
X-Git-Url: http://git.marmaro.de/?p=mmh;a=commitdiff_plain;h=d7b4f0034bc4f5b5c2f990d0984858e9b6f4131a

scansbr: Removed the ``performance hack'' for inc as it wasn't faster.
I tested a 150MB/500msgs mbox but couldn't see any time differences. In both
cases it took 2-5s on my machine. Hence, I go for the much simpler and not
``we use strange internals'' version. If you really inc much larger mboxes,
then just take some time. ;-)
The explaining comment for the hack had been:
    Performance hack: some people like to run "inc" on things like
    net.sources or large digests. We do a copy directly into the output
    buffer rather than going through an intermediate buffer.
        We need the amount of data m_getfld found & don't want to do a
    strlen on the long buffer so there's a hack in m_getfld to save the
    amount of data it returned in the global "msg_count".
---

diff --git a/uip/scansbr.c b/uip/scansbr.c
index 299027a..7dedf70 100644
--- a/uip/scansbr.c
+++ b/uip/scansbr.c
@@ -219,41 +219,11 @@ scan(FILE *inb, int innum, int outnum, char *fmtstr, int width, int curflg,
 			}
 			FPUTS("\n");
 			FPUTS(tmpbuf);
-			/*
-			** performance hack: some people like to run "inc"
-			** on things like net.sources or large digests.
-			** We do a copy directly into the output buffer
-			** rather than going through an intermediate buffer.
-			**
-			** We need the amount of data m_getfld found &
-			** don't want to do a strlen on the long buffer so
-			** there's a hack in m_getfld to save the amount
-			** of data it returned in the global "msg_count".
-			*/
 body:;
 			while (state == BODY) {
-#ifdef LINUX_STDIO
-				if (scnout->_IO_write_ptr == scnout->_IO_write_end) {
-#elif defined(__DragonFly__)
-				if (((struct __FILE_public *)scnout)->_w <= 0) {
-#else
-				if (scnout->_cnt <= 0) {
-#endif
-					if (fflush(scnout) == EOF)
-						adios(scnmsg, "write error on");
-				}
-#ifdef LINUX_STDIO
-				state = m_getfld(state, name, scnout->_IO_write_ptr, (long)scnout->_IO_write_ptr-(long)scnout->_IO_write_end , inb);
-				scnout->_IO_write_ptr += msg_count;
-#elif defined(__DragonFly__)
-				state = m_getfld(state, name, ((struct __FILE_public *)scnout)->_p, -(((struct __FILE_public *)scnout)->_w), inb);
-				((struct __FILE_public *)scnout)->_w -= msg_count;
-				((struct __FILE_public *)scnout)->_p += msg_count;
-#else
-				state = m_getfld(state, name, scnout->_ptr, -(scnout->_cnt), inb);
-				scnout->_cnt -= msg_count;
-				scnout->_ptr += msg_count;
-#endif
+				state = m_getfld(state, name, tmpbuf, SBUFSIZ,
+						inb);
+				FPUTS(tmpbuf);
 			}
 			goto finished;