diff options
| author | Arthur de Jong <arthur@arthurdejong.org> | 2008-01-01 21:53:44 +0100 |
|---|---|---|
| committer | Arthur de Jong <arthur@arthurdejong.org> | 2008-01-01 21:53:44 +0100 |
| commit | 024fde50cc416a089bd1240cd993716557f14bae (patch) | |
| tree | 38d4d006b232c40629d98af161e5f1030eace3d0 /common/tio.c | |
| parent | cbcd0904ad5e15282b1836e452ebeb6d3d03c29e (diff) | |
add limited implementation of tio_mark() and tio_reset() functions to do limited seeks in the read stream, clean up header file comments and write tests for new code
git-svn-id: http://arthurdejong.org/svn/nss-pam-ldapd/nss-ldapd@547 ef36b2f9-881f-0410-afb5-c4e39611909c
Diffstat (limited to 'common/tio.c')
| -rw-r--r-- | common/tio.c | 65 |
1 files changed, 51 insertions, 14 deletions
diff --git a/common/tio.c b/common/tio.c index 744fe5e..6a2244c 100644 --- a/common/tio.c +++ b/common/tio.c @@ -2,7 +2,7 @@ tio.c - timed io functions This file is part of the nss-ldapd library. - Copyright (C) 2007 Arthur de Jong + Copyright (C) 2007, 2008 Arthur de Jong This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public @@ -60,6 +60,7 @@ struct tio_fileinfo { struct tio_buffer *writebuffer; struct timeval readtimeout; struct timeval writetimeout; + int read_resettable; /* whether the tio_reset() function can be called */ #ifdef DEBUG_TIO_STATS /* this is used to collect statistics on the use of the streams and can be used to tune the buffer sizes */ @@ -156,6 +157,7 @@ TFILE *tio_fdopen(int fd,struct timeval *readtimeout,struct timeval *writetimeou fp->readtimeout.tv_usec=readtimeout->tv_usec; fp->writetimeout.tv_sec=writetimeout->tv_sec; fp->writetimeout.tv_usec=writetimeout->tv_usec; + fp->read_resettable=0; #ifdef DEBUG_TIO_STATS fp->byteswritten=0; fp->bytesread=0; @@ -221,10 +223,9 @@ int tio_read(TFILE *fp, void *buf, size_t count) /* loop until we have returned all the needed data */ while (1) { - /* return any data already in the buffer */ + /* check if we have enough data in the buffer */ if (fp->readbuffer->len >= count) { - /* we have enough data in our buffer */ if (count>0) { if (ptr!=NULL) @@ -235,26 +236,32 @@ int tio_read(TFILE *fp, void *buf, size_t count) } return 0; } - else + /* empty what we have and continue from there */ + if (fp->readbuffer->len > 0) { - /* empty what we have and continue from there */ - if (fp->readbuffer->len > 0) + if (ptr!=NULL) { - if (ptr!=NULL) - memcpy(ptr,fp->readbuffer->buffer+fp->readbuffer->start,fp->readbuffer->len); - count-=fp->readbuffer->len; - if (ptr!=NULL) - ptr+=fp->readbuffer->len; + memcpy(ptr,fp->readbuffer->buffer+fp->readbuffer->start,fp->readbuffer->len); + ptr+=fp->readbuffer->len; } - /* flag the buffer as empty */ + count-=fp->readbuffer->len; + } + /* if we have room in the buffer for more don't clear the buffer */ + if ((fp->read_resettable)&&((fp->readbuffer->start+fp->readbuffer->len)<TIO_BUFFERSIZE)) + { + fp->readbuffer->start+=fp->readbuffer->len; + } + else + { fp->readbuffer->start=0; - fp->readbuffer->len=0; + fp->read_resettable=0; } + fp->readbuffer->len=0; /* wait until we have input */ if (tio_select(fp->fd,1,&deadline)) return -1; /* read the input in the buffer */ - rv=read(fp->fd,fp->readbuffer->buffer,TIO_BUFFERSIZE); + rv=read(fp->fd,fp->readbuffer->buffer+fp->readbuffer->start,TIO_BUFFERSIZE-fp->readbuffer->start); /* check for errors */ if ((rv==0)||((rv<0)&&(errno!=EINTR)&&(errno!=EAGAIN))) return -1; /* something went wrong with the read */ @@ -386,3 +393,33 @@ int tio_close(TFILE *fp) /* return the result of the earlier operations */ return retv; } + +void tio_mark(TFILE *fp) +{ + /* ensure that we have a read buffer */ + if (fp->readbuffer==NULL) + { + fp->readbuffer=tio_buffer_new(); + if (fp->readbuffer==NULL) + return; /* error allocating buffer */ + } + /* move any data in the buffer to the start of the buffer */ + if ((fp->readbuffer->start>0)&&(fp->readbuffer->len>0)) + { + memmove(fp->readbuffer->buffer,fp->readbuffer->buffer+fp->readbuffer->start,fp->readbuffer->len); + fp->readbuffer->start=0; + } + /* mark the stream as resettable */ + fp->read_resettable=1; +} + +int tio_reset(TFILE *fp) +{ + /* check if the stream is (still) resettable */ + if ((!fp->read_resettable)||(fp->readbuffer==NULL)) + return -1; + /* reset the buffer */ + fp->readbuffer->len+=fp->readbuffer->start; + fp->readbuffer->start=0; + return 0; +} |