[9fans] bio bug

[9fans] bio bug

[Caerwyn Jones]

The following bug in libbio occurs when seeking within the buffer:

; cat b1.c
#include <u.h>
#include <libc.h>
#include <bio.h>

void
main(int, char *argv[])
{
    Biobuf *bin;
    long r, n;

    bin = Bopen(argv[1], OREAD);
    n = Bseek(bin, 0, 2);
    Bseek(bin, n/2, 0);
    while((r = Bgetrune(bin)) != Beof)
        print("%C", r);

    Bseek(bin, 0, 0);
    while((r = Bgetrune(bin)) != Beof)
        print("%C", r);
    exits(0);
}

; 8c b1.c ; 8l b1.8
; cat t1
a
b
; ./8.out t1
b
b
;

What I should be getting is
b
a
b

Here is the fix.

; diff /sys/src/libbio/bgetc.c bgetc.c
29a30
>   bp->state = Bracteof;

-Caerwyn

Re: [9fans] bio bug

[David Presotto]

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Sorry, it tool me so long.  Your fix is now on sources.

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From: Caerwyn Jones <caerwyn@comcast.net>
To: 9fans@cse.psu.edu
Subject: [9fans] bio bug
Date: Wed, 17 Sep 2003 09:08:33 GMT
Message-ID: <YBO9b.367920$cF.108332@rwcrnsc53>

The following bug in libbio occurs when seeking within the buffer:

; cat b1.c
#include <u.h>
#include <libc.h>
#include <bio.h>

void
main(int, char *argv[])
{
    Biobuf *bin;
    long r, n;

    bin = Bopen(argv[1], OREAD);
    n = Bseek(bin, 0, 2);
    Bseek(bin, n/2, 0);
    while((r = Bgetrune(bin)) != Beof)
        print("%C", r);

    Bseek(bin, 0, 0);
    while((r = Bgetrune(bin)) != Beof)
        print("%C", r);
    exits(0);
}

; 8c b1.c ; 8l b1.8
; cat t1
a
b
; ./8.out t1
b
b
;

What I should be getting is
b
a
b

Here is the fix.

; diff /sys/src/libbio/bgetc.c bgetc.c
29a30
>   bp->state = Bracteof;

-Caerwyn