summaryrefslogtreecommitdiff
path: root/libbio/binit.c
diff options
context:
space:
mode:
Diffstat (limited to 'libbio/binit.c')
-rw-r--r--libbio/binit.c154
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;
+}