diff options
Diffstat (limited to 'libbio/binit.c')
-rw-r--r-- | libbio/binit.c | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/libbio/binit.c b/libbio/binit.c new file mode 100644 index 0000000..19dbed0 --- /dev/null +++ b/libbio/binit.c @@ -0,0 +1,154 @@ +#include <stdlib.h> +#include <plan9.h> +#include <bio.h> + +enum +{ + MAXBUFS = 20 +}; + +static Biobuf* wbufs[MAXBUFS]; +static int atexitflag; + +static +void +batexit(void) +{ + Biobuf *bp; + int i; + + for(i=0; i<MAXBUFS; i++) { + bp = wbufs[i]; + if(bp != 0) { + wbufs[i] = 0; + Bflush(bp); + } + } +} + +static +void +deinstall(Biobuf *bp) +{ + int i; + + for(i=0; i<MAXBUFS; i++) + if(wbufs[i] == bp) + wbufs[i] = 0; +} + +static +void +install(Biobuf *bp) +{ + int i; + + deinstall(bp); + for(i=0; i<MAXBUFS; i++) + if(wbufs[i] == 0) { + wbufs[i] = bp; + break; + } + if(atexitflag == 0) { + atexitflag = 1; + atexit(batexit); + } +} + +int +Binits(Biobuf *bp, int f, int mode, unsigned char *p, int size) +{ + + p += Bungetsize; /* make room for Bungets */ + size -= Bungetsize; + + switch(mode&~(OCEXEC|ORCLOSE|OTRUNC)) { + default: + fprint(2, "Bopen: unknown mode %d\n", mode); + return Beof; + + case OREAD: + bp->state = Bractive; + bp->ocount = 0; + break; + + case OWRITE: + install(bp); + bp->state = Bwactive; + bp->ocount = -size; + break; + } + bp->bbuf = p; + bp->ebuf = p+size; + bp->bsize = size; + bp->icount = 0; + bp->gbuf = bp->ebuf; + bp->fid = f; + bp->flag = 0; + bp->rdline = 0; + bp->offset = 0; + bp->runesize = 0; + return 0; +} + + +int +Binit(Biobuf *bp, int f, int mode) +{ + return Binits(bp, f, mode, bp->b, sizeof(bp->b)); +} + +Biobuf* +Bfdopen(int f, int mode) +{ + Biobuf *bp; + + bp = malloc(sizeof(Biobuf)); + if(bp == 0) + return 0; + Binits(bp, f, mode, bp->b, sizeof(bp->b)); + bp->flag = Bmagic; + return bp; +} + +Biobuf* +Bopen(const char *name, int mode) +{ + Biobuf *bp; + int f; + + switch(mode&~(OCEXEC|ORCLOSE|OTRUNC)) { + default: + fprint(2, "Bopen: unknown mode %d\n", mode); + return 0; + + case OREAD: + f = open(name, OREAD); + if(f < 0) + return 0; + break; + + case OWRITE: + f = creat(name, 0666); + if(f < 0) + return 0; + } + bp = Bfdopen(f, mode); + if(bp == 0) + close(f); + return bp; +} + +int +Bterm(Biobuf *bp) +{ + + deinstall(bp); + Bflush(bp); + if(bp->flag == Bmagic) { + bp->flag = 0; + close(bp->fid); + free(bp); + } + return 0; +} |